The second heart sound (S2) is created by vibrations produced when the aortic and pulmonary valves close. It marks the end of systole. It is normal to hear a split in the sound during inspiration.

A loud S2 can be associated with certain conditions such as systemic hypertension (resulting in a loud A2), pulmonary hypertension (resulting in a loud P2), hyperdynamic states (like tachycardia, fever, or thyrotoxicosis), and atrial septal defect (which causes a loud P2).

On the other hand, a soft S2 can be linked to decreased aortic diastolic pressure (as seen in aortic regurgitation), poorly mobile cusps (such as calcification of the aortic valve), aortic root dilatation, and pulmonary stenosis (which causes a soft P2).

A widely split S2 can occur during deep inspiration, right bundle branch block, prolonged right ventricular systole (seen in conditions like pulmonary stenosis or pulmonary embolism), and severe mitral regurgitation. However, in the case of atrial septal defect, the splitting is fixed and does not vary with respiration.

Reversed splitting of S2, where P2 occurs before A2 (paradoxical splitting), can occur during deep expiration, left bundle branch block, prolonged left ventricular systole (as seen in hypertrophic cardiomyopathy), severe aortic stenosis, and right ventricular pacing.

Acute aortic dissection is characterized by the rapid formation of a false, blood-filled channel within the middle layer of the aorta. It is estimated to occur in 3 out of every 100,000 individuals per year.

Patients with aortic dissection typically experience intense chest pain that spreads to the area between the shoulder blades. The pain is often described as tearing or ripping and may also extend to the neck. Sweating, paleness, and rapid heartbeat are commonly observed at the time of presentation. Other possible symptoms include focal neurological deficits, weak pulses, fainting, and reduced blood flow to organs.

A significant difference in blood pressure between the arms, greater than 20 mmHg, is a highly sensitive indicator. If the dissection extends backward, it can involve the aortic valve, leading to the early diastolic murmur of aortic regurgitation.

Risk factors for aortic dissection include hypertension, atherosclerosis, aortic coarctation, the use of sympathomimetic drugs like cocaine, Marfan syndrome, Ehlers-Danlos syndrome, Turner’s syndrome, tertiary syphilis, and pre-existing aortic aneurysm.

Aortic dissection can be classified according to the Stanford classification system:
– Type A affects the ascending aorta and the arch, accounting for 60% of cases. These cases are typically managed surgically and may result in the blockage of coronary arteries and aortic regurgitation.
– Type B begins distal to the left subclavian artery and accounts for approximately 40% of cases. These cases are usually managed with medication to control blood pressure.

An abnormal QTc, which is the measurement of the time it takes for the heart to recharge between beats, is generally considered to be greater than 450 ms in males. However, some sources may use a cutoff of greater than 440 ms as abnormal in males. To further categorize the QTc, a measurement of 430ms or less is considered normal, 431-450 ms is borderline, and 450 ms or more is considered abnormal in males. Females typically have a longer QTc, so the categories for them are often quoted as less than 450 ms being normal, 451-470 ms being borderline, and greater than 470ms being abnormal.

Further Reading:

Long QT syndrome (LQTS) is a condition characterized by a prolonged QT interval on an electrocardiogram (ECG), which represents abnormal repolarization of the heart. LQTS can be either acquired or congenital. Congenital LQTS is typically caused by gene abnormalities that affect ion channels responsible for potassium or sodium flow in the heart. There are 15 identified genes associated with congenital LQTS, with three genes accounting for the majority of cases. Acquired LQTS can be caused by various factors such as certain medications, electrolyte imbalances, hypothermia, hypothyroidism, and bradycardia from other causes.

The normal QTc values, which represent the corrected QT interval for heart rate, are typically less than 450 ms for men and less than 460ms for women. Prolonged QTc intervals are considered to be greater than these values. It is important to be aware of drugs that can cause QT prolongation, as this can lead to potentially fatal arrhythmias. Some commonly used drugs that can cause QT prolongation include antimicrobials, antiarrhythmics, antipsychotics, antidepressants, antiemetics, and others.

Management of long QT syndrome involves addressing any underlying causes and using beta blockers. In some cases, an implantable cardiac defibrillator (ICD) may be recommended for patients who have experienced recurrent arrhythmic syncope, documented torsades de pointes, previous ventricular tachyarrhythmias or torsades de pointes, previous cardiac arrest, or persistent syncope. Permanent pacing may be used in patients with bradycardia or atrioventricular nodal block and prolonged QT. Mexiletine is a treatment option for those with LQT3. Cervicothoracic sympathetic denervation may be considered in patients with recurrent syncope despite beta-blockade or in those who are not ideal candidates for an ICD. The specific treatment options for LQTS depend on the type and severity of the condition.

Q waves in V2 and V3 are typically abnormal and indicate a pathological condition. Q waves are negative deflections that occur before an R wave. They can be either normal or abnormal. Small normal Q waves, which are less than 1mm deep, may be present in most leads. Deeper normal Q waves are commonly seen in lead III, as long as they are not present in the adjacent leads II and AVF. On the other hand, pathological Q waves are usually deeper and wider. In particular, Q waves should not be observed in V2 and V3. The specific criteria for identifying pathological Q waves are as follows: any Q wave in leads V2-V3 that is greater than 0.02s in duration or a QS complex in leads V2-V3; a Q wave that is greater than 0.03s in duration and deeper than 1mm, or a QS complex, in leads I, II, aVL, aVF, or V4-V6 in any two leads of a contiguous lead grouping; an R wave that is greater than 0.04s in duration in V1-V2 and has an R/S ratio greater than 1, along with a concordant positive T wave, in the absence of a conduction defect. In healthy individuals, the T-wave is normally inverted in aVR and inverted or flat in V1. T-wave inversion in III is also considered a normal variation. If there is ST elevation in lead V1, it would suggest a ST-elevation myocardial infarction (STEMI) rather than a non-ST-elevation myocardial infarction (NSTEMI).

Further Reading:

Acute Coronary Syndromes (ACS) is a term used to describe a group of conditions that involve the sudden reduction or blockage of blood flow to the heart. This can lead to a heart attack or unstable angina. ACS includes ST segment elevation myocardial infarction (STEMI), non-ST segment elevation myocardial infarction (NSTEMI), and unstable angina (UA).

The development of ACS is usually seen in patients who already have underlying coronary heart disease. This disease is characterized by the buildup of fatty plaques in the walls of the coronary arteries, which can gradually narrow the arteries and reduce blood flow to the heart. This can cause chest pain, known as angina, during physical exertion. In some cases, the fatty plaques can rupture, leading to a complete blockage of the artery and a heart attack.

There are both non modifiable and modifiable risk factors for ACS. non modifiable risk factors include increasing age, male gender, and family history. Modifiable risk factors include smoking, diabetes mellitus, hypertension, hypercholesterolemia, and obesity.

The symptoms of ACS typically include chest pain, which is often described as a heavy or constricting sensation in the central or left side of the chest. The pain may also radiate to the jaw or left arm. Other symptoms can include shortness of breath, sweating, and nausea/vomiting. However, it’s important to note that some patients, especially diabetics or the elderly, may not experience chest pain.

The diagnosis of ACS is typically made based on the patient’s history, electrocardiogram (ECG), and blood tests for cardiac enzymes, specifically troponin. The ECG can show changes consistent with a heart attack, such as ST segment elevation or depression, T wave inversion, or the presence of a new left bundle branch block. Elevated troponin levels confirm the diagnosis of a heart attack.

The management of ACS depends on the specific condition and the patient’s risk factors. For STEMI, immediate coronary reperfusion therapy, either through primary percutaneous coronary intervention (PCI) or fibrinolysis, is recommended. In addition to aspirin, a second antiplatelet agent is usually given. For NSTEMI or unstable angina, the treatment approach may involve reperfusion therapy or medical management, depending on the patient’s risk of future cardiovascular events.

Mitral regurgitation is characterized by a continuous murmur throughout systole that is often heard loudest at the apex and can be heard radiating to the left axilla.

Further Reading:

Mitral Stenosis:
– Causes: Rheumatic fever, Mucopolysaccharidoses, Carcinoid, Endocardial fibroelastosis
– Features: Mid-late diastolic murmur, loud S1, opening snap, low volume pulse, malar flush, atrial fibrillation, signs of pulmonary edema, tapping apex beat
– Features of severe mitral stenosis: Length of murmur increases, opening snap becomes closer to S2
– Investigation findings: CXR may show left atrial enlargement, echocardiography may show reduced cross-sectional area of the mitral valve

Mitral Regurgitation:
– Causes: Mitral valve prolapse, Myxomatous degeneration, Ischemic heart disease, Rheumatic fever, Connective tissue disorders, Endocarditis, Dilated cardiomyopathy
– Features: pansystolic murmur radiating to left axilla, soft S1, S3, laterally displaced apex beat with heave
– Signs of acute MR: Decompensated congestive heart failure symptoms
– Signs of chronic MR: Leg edema, fatigue, arrhythmia (atrial fibrillation)
– Investigation findings: Doppler echocardiography to detect regurgitant flow and pulmonary hypertension, ECG may show signs of LA enlargement and LV hypertrophy, CXR may show LA and LV enlargement in chronic MR and pulmonary edema in acute MR.

The most appropriate initial treatment for this patient would be intravenous labetalol. Labetalol is a non-selective beta blocker with alpha-blocking properties. It is the preferred initial treatment for aortic dissection because it helps to reduce blood pressure and heart rate, which can help to decrease the shear forces acting on the aortic wall and prevent further dissection. Intravenous administration of labetalol allows for rapid and effective control of blood pressure.

Other treatment options, such as intravenous magnesium sulphate, intravenous verapamil, GTN sublingual spray, and oral nifedipine, are not appropriate for the management of aortic dissection. Magnesium sulphate is used for the treatment of certain arrhythmias and pre-eclampsia, but it does not address the underlying issue of aortic dissection. Verapamil and nifedipine are calcium channel blockers that can lower blood pressure, but they can also cause reflex tachycardia, which can worsen the condition. GTN sublingual spray is used for the treatment of angina, but it does not address the underlying issue of aortic dissection.

Further Reading:

Aortic dissection is a life-threatening condition in which blood flows through a tear in the innermost layer of the aorta, creating a false lumen. Prompt treatment is necessary as the mortality rate increases by 1-2% per hour. There are different classifications of aortic dissection, with the majority of cases being proximal. Risk factors for aortic dissection include hypertension, atherosclerosis, connective tissue disorders, family history, and certain medical procedures.

The presentation of aortic dissection typically includes sudden onset sharp chest pain, often described as tearing or ripping. Back pain and abdominal pain are also common, and the pain may radiate to the neck and arms. The clinical picture can vary depending on which aortic branches are affected, and complications such as organ ischemia, limb ischemia, stroke, myocardial infarction, and cardiac tamponade may occur. Common signs and symptoms include a blood pressure differential between limbs, pulse deficit, and a diastolic murmur.

Various investigations can be done to diagnose aortic dissection, including ECG, CXR, and CT with arterial contrast enhancement (CTA). CT is the investigation of choice due to its accuracy in diagnosis and classification. Other imaging techniques such as transoesophageal echocardiography (TOE), magnetic resonance imaging/angiography (MRI/MRA), and digital subtraction angiography (DSA) are less commonly used.

Management of aortic dissection involves pain relief, resuscitation measures, blood pressure control, and referral to a vascular or cardiothoracic team. Opioid analgesia should be given for pain relief, and resuscitation measures such as high flow oxygen and large bore IV access should be performed. Blood pressure control is crucial, and medications such as labetalol may be used to reduce systolic blood pressure. Hypotension carries a poor prognosis and may require careful fluid resuscitation. Treatment options depend on the type of dissection, with type A dissections typically requiring urgent surgery and type B dissections managed by thoracic endovascular aortic repair (TEVAR) and blood pressure control optimization.

Atropine should not be given to patients with certain conditions, including heart transplant, angle-closure glaucoma, gastrointestinal motility disorders, myasthenia gravis, severe ulcerative colitis, toxic megacolon, bladder outflow obstruction, and urinary retention. In heart transplant patients, atropine will not have the desired effect as the denervated hearts do not respond to vagal blockade. Giving atropine in these patients may even lead to paradoxical sinus arrest or high-grade AV block.

Further Reading:

Causes of Bradycardia:
– Physiological: Athletes, sleeping
– Cardiac conduction dysfunction: Atrioventricular block, sinus node disease
– Vasovagal & autonomic mediated: Vasovagal episodes, carotid sinus hypersensitivity
– Hypothermia
– Metabolic & electrolyte disturbances: Hypothyroidism, hyperkalaemia, hypermagnesemia
– Drugs: Beta-blockers, calcium channel blockers, digoxin, amiodarone
– Head injury: Cushing’s response
– Infections: Endocarditis
– Other: Sarcoidosis, amyloidosis

Presenting symptoms of Bradycardia:
– Presyncope (dizziness, lightheadedness)
– Syncope
– Breathlessness
– Weakness
– Chest pain
– Nausea

Management of Bradycardia:
– Assess and monitor for adverse features (shock, syncope, myocardial ischaemia, heart failure)
– Treat reversible causes of bradycardia
– Pharmacological treatment: Atropine is first-line, adrenaline and isoprenaline are second-line
– Transcutaneous pacing if atropine is ineffective
– Other drugs that may be used: Aminophylline, dopamine, glucagon, glycopyrrolate

Bradycardia Algorithm:
– Follow the algorithm for management of bradycardia, which includes assessing and monitoring for adverse features, treating reversible causes, and using appropriate medications or pacing as needed.
https://acls-algorithms.com/wp-content/uploads/2020/12/Website-Bradycardia-Algorithm-Diagram.pdf

The majority of dissections happen in individuals between the ages of 40 and 70, with the highest occurrence observed in the age group of 50 to 65.

Further Reading:

Aortic dissection is a life-threatening condition in which blood flows through a tear in the innermost layer of the aorta, creating a false lumen. Prompt treatment is necessary as the mortality rate increases by 1-2% per hour. There are different classifications of aortic dissection, with the majority of cases being proximal. Risk factors for aortic dissection include hypertension, atherosclerosis, connective tissue disorders, family history, and certain medical procedures.

The presentation of aortic dissection typically includes sudden onset sharp chest pain, often described as tearing or ripping. Back pain and abdominal pain are also common, and the pain may radiate to the neck and arms. The clinical picture can vary depending on which aortic branches are affected, and complications such as organ ischemia, limb ischemia, stroke, myocardial infarction, and cardiac tamponade may occur. Common signs and symptoms include a blood pressure differential between limbs, pulse deficit, and a diastolic murmur.

Various investigations can be done to diagnose aortic dissection, including ECG, CXR, and CT with arterial contrast enhancement (CTA). CT is the investigation of choice due to its accuracy in diagnosis and classification. Other imaging techniques such as transoesophageal echocardiography (TOE), magnetic resonance imaging/angiography (MRI/MRA), and digital subtraction angiography (DSA) are less commonly used.

Management of aortic dissection involves pain relief, resuscitation measures, blood pressure control, and referral to a vascular or cardiothoracic team. Opioid analgesia should be given for pain relief, and resuscitation measures such as high flow oxygen and large bore IV access should be performed. Blood pressure control is crucial, and medications such as labetalol may be used to reduce systolic blood pressure. Hypotension carries a poor prognosis and may require careful fluid resuscitation. Treatment options depend on the type of dissection, with type A dissections typically requiring urgent surgery and type B dissections managed by thoracic endovascular aortic repair (TEVAR) and blood pressure control optimization.

One of the signs of digoxin toxicity is yellow-green vision. Other clinical features include feeling generally unwell, lethargy, nausea and vomiting, loss of appetite, confusion, and the development of arrhythmias such as AV block and bradycardia.

Further Reading:

Digoxin is a medication used for rate control in atrial fibrillation and for improving symptoms in heart failure. It works by decreasing conduction through the atrioventricular node and increasing the force of cardiac muscle contraction. However, digoxin toxicity can occur, and plasma concentration alone does not determine if a patient has developed toxicity. Symptoms of digoxin toxicity include feeling generally unwell, lethargy, nausea and vomiting, anorexia, confusion, yellow-green vision, arrhythmias, and gynaecomastia.

ECG changes seen in digoxin toxicity include downsloping ST depression with a characteristic Salvador Dali sagging appearance, flattened, inverted, or biphasic T waves, shortened QT interval, mild PR interval prolongation, and prominent U waves. There are several precipitating factors for digoxin toxicity, including hypokalaemia, increasing age, renal failure, myocardial ischaemia, electrolyte imbalances, hypoalbuminaemia, hypothermia, hypothyroidism, and certain medications such as amiodarone, quinidine, verapamil, and diltiazem.

Management of digoxin toxicity involves the use of digoxin specific antibody fragments, also known as Digibind or digifab. Arrhythmias should be treated, and electrolyte disturbances should be corrected with close monitoring of potassium levels. It is important to note that digoxin toxicity can be precipitated by hypokalaemia, and toxicity can then lead to hyperkalaemia.

Amiodarone is recommended to be administered after the third shock in a shockable cardiac arrest (Vf/pVT) while performing chest compressions. The prescribed dose is 300 mg, which should be given as an intravenous bolus. To ensure proper administration, the medication should be diluted in 20 mL of 5% dextrose solution.

In cases where VF/pVT continues after five defibrillation attempts, an additional dose of 150 mg of Amiodarone should be administered. It is important to note that Amiodarone is not suitable for treating PEA or asystole, and its use is specifically indicated for shockable cardiac arrest situations.

Distinguishing between unstable angina and other acute coronary syndromes can be done by looking at normal troponin results. If serial troponin tests come back negative, it can rule out a diagnosis of myocardial infarction. Unstable angina is characterized by myocardial ischemia occurring at rest or with minimal exertion, without any acute damage or death of heart muscle cells. The patient in question shows ECG and biochemical features that align with this definition. Vincent’s angina, on the other hand, refers to an infection in the throat accompanied by ulcerative gingivitis.

Further Reading:

Acute Coronary Syndromes (ACS) is a term used to describe a group of conditions that involve the sudden reduction or blockage of blood flow to the heart. This can lead to a heart attack or unstable angina. ACS includes ST segment elevation myocardial infarction (STEMI), non-ST segment elevation myocardial infarction (NSTEMI), and unstable angina (UA).

The development of ACS is usually seen in patients who already have underlying coronary heart disease. This disease is characterized by the buildup of fatty plaques in the walls of the coronary arteries, which can gradually narrow the arteries and reduce blood flow to the heart. This can cause chest pain, known as angina, during physical exertion. In some cases, the fatty plaques can rupture, leading to a complete blockage of the artery and a heart attack.

There are both non modifiable and modifiable risk factors for ACS. non modifiable risk factors include increasing age, male gender, and family history. Modifiable risk factors include smoking, diabetes mellitus, hypertension, hypercholesterolemia, and obesity.

The symptoms of ACS typically include chest pain, which is often described as a heavy or constricting sensation in the central or left side of the chest. The pain may also radiate to the jaw or left arm. Other symptoms can include shortness of breath, sweating, and nausea/vomiting. However, it’s important to note that some patients, especially diabetics or the elderly, may not experience chest pain.

The diagnosis of ACS is typically made based on the patient’s history, electrocardiogram (ECG), and blood tests for cardiac enzymes, specifically troponin. The ECG can show changes consistent with a heart attack, such as ST segment elevation or depression, T wave inversion, or the presence of a new left bundle branch block. Elevated troponin levels confirm the diagnosis of a heart attack.

The management of ACS depends on the specific condition and the patient’s risk factors. For STEMI, immediate coronary reperfusion therapy, either through primary percutaneous coronary intervention (PCI) or fibrinolysis, is recommended. In addition to aspirin, a second antiplatelet agent is usually given. For NSTEMI or unstable angina, the treatment approach may involve reperfusion therapy or medical management, depending on the patient’s risk of future cardiovascular events.

Cardiac enzymes do not increase in unstable angina. However, if cardiac markers do rise, it is classified as a non-ST elevation myocardial infarction (NSTEMI). Both unstable angina and NSTEMI can have a normal ECG. An extended ventricular activation time indicates damage to the heart muscle. This occurs because infarcting myocardium conducts electrical impulses at a slower pace, resulting in a prolonged interval between the start of the QRS complex and the apex of the R wave. A positive troponin test indicates the presence of necrosis in cardiac myocytes.

Summary:
Marker | Initial Rise | Peak | Normal at
Creatine kinase | 4-8 hours | 18 hours 2-3 days | CK-MB = main cardiac isoenzyme
Myoglobin | 1-4 hours | 6-7 hours | 24 hours | Low specificity due to skeletal muscle damage
Troponin I | 3-12 hours | 24 hours | 3-10 days | Appears to be the most sensitive and specific
HFABP | 1-2 hours | 5-10 hours | 24 hours | HFABP = heart fatty acid binding protein
LDH | 10 hours | 24-48 hours | 14 days | Cardiac muscle mainly contains LDH

The timing of the initial rise, peak, and return to normality of various cardiac enzymes can serve as a helpful guide. Creatine kinase, the main cardiac isoenzyme, typically experiences an initial rise within 4-8 hours, reaches its peak at 18 hours, and returns to normal within 2-3 days. Myoglobin, which lacks specificity due to its association with skeletal muscle damage, shows an initial rise within 1-4 hours, peaks at 6-7 hours, and returns to normal within 24 hours. Troponin I, known for its sensitivity and specificity, exhibits an initial rise within 3-12 hours, reaches its peak at 24 hours, and returns to normal within 3-10 days. HFABP, or heart fatty acid binding protein, experiences an initial rise within 1.5 hours, peaks at 5-10 hours, and returns to normal within 24 hours. Lastly, LDH, predominantly found in cardiac muscle, shows an initial rise at 10 hours, peaks at 24-48 hours, and returns to normal within 14 days.

This patient is displaying symptoms consistent with a diagnosis of an acute myocardial infarction. It is important to provide pain relief as soon as possible. One option for pain relief is GTN, which can be taken sublingually or buccally. However, if there is suspicion of an acute myocardial infarction, it is recommended to offer intravenous opioids such as morphine.

Aspirin should be offered to all patients with unstable angina or NSTEMI as soon as possible and should be continued indefinitely, unless there are contraindications such as a bleeding risk or aspirin hypersensitivity. A loading dose of 300 mg should be administered promptly after presentation.

For patients without a high bleeding risk who do not have coronary angiography planned within 24 hours of admission, fondaparinux should be administered. However, for patients who are likely to undergo coronary angiography within 24 hours, unfractionated heparin can be offered as an alternative to fondaparinux. In cases of significant renal impairment (creatinine above 265 micromoles per litre), unfractionated heparin with dose adjustment guided by clotting function monitoring can also be considered as an alternative to fondaparinux.

Routine administration of oxygen is no longer recommended, but it is important to monitor oxygen saturation using pulse oximetry as soon as possible, preferably before hospital admission. Supplemental oxygen should only be offered to individuals with an oxygen saturation (SpO2) of less than 94% who are not at risk of hypercapnic respiratory failure, with a target SpO2 range of 94-98%. For individuals with chronic obstructive pulmonary disease who are at risk of hypercapnic respiratory failure, a target SpO2 range of 88-92% should be aimed for until blood gas analysis is available.

Bivalirudin, a specific and reversible direct thrombin inhibitor (DTI), is recommended by NICE as a possible treatment for adults with STEMI who are undergoing percutaneous coronary intervention.

For more information, please refer to the NICE guidelines on the assessment and diagnosis of chest pain of recent onset.

The classic ECG features of atrial fibrillation include an irregularly irregular rhythm, the absence of p-waves, an irregular ventricular rate, and the presence of fibrillation waves. This irregular rhythm occurs because the atrial impulses are filtered out by the AV node.

In addition, Ashman beats may be observed in atrial fibrillation. These beats are characterized by wide complex QRS complexes, often with a morphology resembling right bundle branch block. They occur after a short R-R interval that is preceded by a prolonged R-R interval. Fortunately, Ashman beats are generally considered harmless.

The disorganized electrical activity in atrial fibrillation typically originates at the root of the pulmonary veins.

Tricuspid regurgitation leads to a pansystolic murmur that is most pronounced in the tricuspid area during inhalation. The primary cause of tricuspid regurgitation is right ventricular failure.

Other clinical signs that may be present in tricuspid regurgitation include a raised jugular venous pressure (JVP) and giant C-V waves. Additionally, features of increased right atrial pressure, such as ascites and dependent edema, may be observed. Pulsatile hepatomegaly and a thrill at the left sternal edge are also possible indicators. Reverse splitting of the second heart sound, due to early closure of the pulmonary valve, and a third heart sound, caused by rapid right ventricular filling, may be heard as well.

Aortic regurgitation, on the other hand, produces an early diastolic murmur that is most audible at the lower left sternal edge when the patient is sitting forward and exhaling.

In the case of mitral stenosis, a rumbling mid-diastolic murmur is best heard at the apex while the patient is in the left lateral position and exhaling, using the bell of the stethoscope.

Atrial myxomas are benign tumors that can develop in the heart. Most commonly found on the left side, they may obstruct the mitral valve, resulting in a mid-diastolic murmur similar to that of mitral stenosis.

Lastly, left anterior descending artery stenosis can cause an early diastolic murmur, also known as Dock’s murmur. This murmur is similar to that of aortic regurgitation and is best heard at the left 2nd or 3rd intercostal space.

A collapsing pulse, also known as a water hammer pulse, is a common clinical feature associated with aortic regurgitation (AR). In AR, the pulse rises rapidly and forcefully before quickly collapsing. This pulsation pattern may also be referred to as Watson’s water hammer pulse or Corrigan’s pulse. Heart sounds in AR are typically quiet, and the second heart sound (S2) may even be absent if the valve fails to fully close. A characteristic early to mid diastolic murmur is often present. Other typical features of AR include a wide pulse pressure, a mid-diastolic Austin-Flint murmur in severe cases, a soft S1 and S2 (with S2 potentially being absent), a hyperdynamic apical pulse, and signs of heart failure such as lung creases, raised jugular venous pressure (JVP), and tachypnea.

Further Reading:

Valvular heart disease refers to conditions that affect the valves of the heart. In the case of aortic valve disease, there are two main conditions: aortic regurgitation and aortic stenosis.

Aortic regurgitation is characterized by an early diastolic murmur, a collapsing pulse (also known as a water hammer pulse), and a wide pulse pressure. In severe cases, there may be a mid-diastolic Austin-Flint murmur due to partial closure of the anterior mitral valve cusps caused by the regurgitation streams. The first and second heart sounds (S1 and S2) may be soft, and S2 may even be absent. Additionally, there may be a hyperdynamic apical pulse. Causes of aortic regurgitation include rheumatic fever, infective endocarditis, connective tissue diseases like rheumatoid arthritis and systemic lupus erythematosus, and a bicuspid aortic valve. Aortic root diseases such as aortic dissection, spondyloarthropathies like ankylosing spondylitis, hypertension, syphilis, and genetic conditions like Marfan’s syndrome and Ehler-Danlos syndrome can also lead to aortic regurgitation.

Aortic stenosis, on the other hand, is characterized by a narrow pulse pressure, a slow rising pulse, and a delayed ESM (ejection systolic murmur). The second heart sound (S2) may be soft or absent, and there may be an S4 (atrial gallop) that occurs just before S1. A thrill may also be felt. The duration of the murmur is an important factor in determining the severity of aortic stenosis. Causes of aortic stenosis include degenerative calcification (most common in older patients), a bicuspid aortic valve (most common in younger patients), William’s syndrome (supravalvular aortic stenosis), post-rheumatic disease, and subvalvular conditions like hypertrophic obstructive cardiomyopathy (HOCM).

Management of aortic valve disease depends on the severity of symptoms. Asymptomatic patients are generally observed, while symptomatic patients may require valve replacement. Surgery may also be considered for asymptomatic patients with a valvular gradient greater than 40 mmHg and features such as left ventricular systolic dysfunction. Balloon valvuloplasty is limited to patients with critical aortic stenosis who are not fit for valve replacement.

For the exam, it is important to be familiar with the statistics regarding the outcomes of outpatient and inpatient cardiac arrest in the UK.

Further Reading:

Cardiopulmonary arrest is a serious event with low survival rates. In non-traumatic cardiac arrest, only about 20% of patients who arrest as an in-patient survive to hospital discharge, while the survival rate for out-of-hospital cardiac arrest is approximately 8%. The Resus Council BLS/AED Algorithm for 2015 recommends chest compressions at a rate of 100-120 per minute with a compression depth of 5-6 cm. The ratio of chest compressions to rescue breaths is 30:2.

After a cardiac arrest, the goal of patient care is to minimize the impact of post cardiac arrest syndrome, which includes brain injury, myocardial dysfunction, the ischaemic/reperfusion response, and the underlying pathology that caused the arrest. The ABCDE approach is used for clinical assessment and general management. Intubation may be necessary if the airway cannot be maintained by simple measures or if it is immediately threatened. Controlled ventilation is aimed at maintaining oxygen saturation levels between 94-98% and normocarbia. Fluid status may be difficult to judge, but a target mean arterial pressure (MAP) between 65 and 100 mmHg is recommended. Inotropes may be administered to maintain blood pressure. Sedation should be adequate to gain control of ventilation, and short-acting sedating agents like propofol are preferred. Blood glucose levels should be maintained below 8 mmol/l. Pyrexia should be avoided, and there is some evidence for controlled mild hypothermia but no consensus on this.

Post ROSC investigations may include a chest X-ray, ECG monitoring, serial potassium and lactate measurements, and other imaging modalities like ultrasonography, echocardiography, CTPA, and CT head, depending on availability and skills in the local department. Treatment should be directed towards the underlying cause, and PCI or thrombolysis may be considered for acute coronary syndrome or suspected pulmonary embolism, respectively.

Patients who are comatose after ROSC without significant pre-arrest comorbidities should be transferred to the ICU for supportive care. Neurological outcome at 72 hours is the best prognostic indicator of outcome.

Brugada syndrome is a genetic disorder that is passed down from one generation to another in an autosomal dominant manner. It is characterized by abnormal findings on an electrocardiogram (ECG) and can lead to sudden cardiac death. The cause of death in individuals with Brugada syndrome is typically ventricular fibrillation, which occurs as a result of specific defects in ion channels that are determined by our genes. Interestingly, this syndrome is more commonly observed in South East Asia and is actually the leading cause of sudden unexplained cardiac death in Thailand.

One of the key features seen on an ECG that is consistent with Type 1 Brugada syndrome is a pattern known as right bundle branch block. Additionally, there is a distinct downward sloping coved ST elevation observed in leads V1-V3. These specific ECG findings help to identify individuals who may be at risk for developing Brugada syndrome and experiencing its potentially fatal consequences.

After the return of spontaneous circulation (ROSC), there are two specific blood pressure targets that need to be achieved. The first target is to maintain a systolic blood pressure above 100 mmHg. The second target is to maintain the mean arterial pressure (MAP) within the range of 65 to 100 mmHg.

Further Reading:

Cardiopulmonary arrest is a serious event with low survival rates. In non-traumatic cardiac arrest, only about 20% of patients who arrest as an in-patient survive to hospital discharge, while the survival rate for out-of-hospital cardiac arrest is approximately 8%. The Resus Council BLS/AED Algorithm for 2015 recommends chest compressions at a rate of 100-120 per minute with a compression depth of 5-6 cm. The ratio of chest compressions to rescue breaths is 30:2.

After a cardiac arrest, the goal of patient care is to minimize the impact of post cardiac arrest syndrome, which includes brain injury, myocardial dysfunction, the ischaemic/reperfusion response, and the underlying pathology that caused the arrest. The ABCDE approach is used for clinical assessment and general management. Intubation may be necessary if the airway cannot be maintained by simple measures or if it is immediately threatened. Controlled ventilation is aimed at maintaining oxygen saturation levels between 94-98% and normocarbia. Fluid status may be difficult to judge, but a target mean arterial pressure (MAP) between 65 and 100 mmHg is recommended. Inotropes may be administered to maintain blood pressure. Sedation should be adequate to gain control of ventilation, and short-acting sedating agents like propofol are preferred. Blood glucose levels should be maintained below 8 mmol/l. Pyrexia should be avoided, and there is some evidence for controlled mild hypothermia but no consensus on this.

Post ROSC investigations may include a chest X-ray, ECG monitoring, serial potassium and lactate measurements, and other imaging modalities like ultrasonography, echocardiography, CTPA, and CT head, depending on availability and skills in the local department. Treatment should be directed towards the underlying cause, and PCI or thrombolysis may be considered for acute coronary syndrome or suspected pulmonary embolism, respectively.

Patients who are comatose after ROSC without significant pre-arrest comorbidities should be transferred to the ICU for supportive care. Neurological outcome at 72 hours is the best prognostic indicator of outcome.

The clinical symptoms of mitral stenosis include shortness of breath, which tends to worsen during exercise and when lying flat. Tiredness, palpitations, ankle swelling, cough, and haemoptysis are also common symptoms. Chest discomfort is rarely reported.

The clinical signs of mitral stenosis can include a malar flush, an irregular pulse if atrial fibrillation is present, a tapping apex beat that can be felt as the first heart sound, and a left parasternal heave if there is pulmonary hypertension. The first heart sound is often loud, and a mid-diastolic murmur can be heard.

The mid-diastolic murmur of mitral stenosis is a rumbling sound that is best heard at the apex, in the left lateral position during expiration, using the bell of the stethoscope.

Mitral stenosis is typically caused by rheumatic heart disease, and it is more common in females, with about two-thirds of patients being female.

Aortic stenosis is a common condition where the valve in the heart becomes narrowed due to the progressive calcification that occurs with age. This typically occurs around the age of 70. Other causes of aortic stenosis include calcification of a congenital bicuspid aortic valve and rheumatic fever.

The symptoms of aortic stenosis can vary but commonly include difficulty breathing during physical activity, fainting, dizziness, chest pain (angina), and in severe cases, sudden death. However, it is also possible for aortic stenosis to be asymptomatic, meaning that there are no noticeable symptoms.

When examining a patient with aortic stenosis, there are several signs that may be present. These include a slow-rising and low-volume pulse, a narrow pulse pressure, a sustained apex beat, a thrill (a vibrating sensation) in the area of the aorta, and an ejection click if the valve is pliable. Additionally, there is typically an ejection systolic murmur, which is a specific type of heart murmur, that can be heard loudest in the aortic area (located at the right sternal edge, 2nd intercostal space) and may radiate to the carotid arteries.

It is important to differentiate aortic stenosis from aortic sclerosis, which is a degeneration of the aortic valve but does not cause obstruction of the left ventricular outflow tract. Aortic sclerosis can be distinguished by the presence of a normal pulse character and the absence of radiation of the murmur.

Currently, there are three beta-blockers that have been approved for the treatment of chronic heart failure. These medications include bisoprolol, carvedilol, and nebivolol.

Chronic HF is a common clinical syndrome resulting from coronary artery disease (CAD), HTN, valvular heart disease, and/or primary cardiomyopathy. There is now conclusive evidence that β-blockers, when added to ACE inhibitors, substantially reduce mortality, decrease sudden death, and improve symptoms in patients with HF. Despite the overwhelming evidence and guidelines that mandate the use of β-blockers in all HF patients without contraindications, many patients do not receive this treatment.

Aortic stenosis leads to the presence of a murmur during the ejection phase of the cardiac cycle. This murmur is most audible at the right second intercostal space and can be heard extending into the right neck.

Mitral regurgitation, on the other hand, produces a high-pitched murmur that occurs throughout the entire systolic phase of the cardiac cycle. This murmur is best heard at the apex of the heart and can be heard radiating into the axilla.

Tricuspid regurgitation is characterized by a blowing murmur that occurs throughout the entire systolic phase of the cardiac cycle. This murmur is most clearly heard at the lower left sternal edge.

Ventricular septal defect results in a harsh murmur that occurs throughout the entire systolic phase of the cardiac cycle. This murmur is best heard at the third or fourth left intercostal space and can be heard radiating throughout the praecordium.

Aortopulmonary shunts are an extremely rare cause of a murmur that occurs throughout the entire systolic phase of the cardiac cycle.

Patients with mitral regurgitation can go for extended periods without experiencing any symptoms. They may have a normal exercise tolerance and show no signs of congestive cardiac failure. However, when cardiac failure does occur, patients often complain of breathlessness, especially during physical exertion. They may also experience fatigue, difficulty breathing while lying flat (orthopnoea), and sudden episodes of difficulty breathing at night (paroxysmal nocturnal dyspnoea).

In terms of clinical signs, mitral regurgitation can be identified through various indicators. These include a displaced and volume loaded apex beat, which can be felt during a physical examination. A palpable thrill may also be detected at the apex. Additionally, a pansystolic murmur, which is loudest at the apex and radiates to the axilla, can be heard. This murmur is typically most pronounced when the patient holds their breath during expiration. Furthermore, a soft first heart sound and signs of left ventricular failure may be present.

According to NICE guidelines, amiodarone is recommended as the initial choice for pharmacological cardioversion of atrial fibrillation (AF) in individuals who have evidence of structural heart disease.

Further Reading:

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting around 5% of patients over the age of 70-75 years and 10% of patients aged 80-85 years. While AF can cause palpitations and inefficient cardiac function, the most important aspect of managing patients with AF is reducing the increased risk of stroke.

AF can be classified as first detected episode, paroxysmal, persistent, or permanent. First detected episode refers to the initial occurrence of AF, regardless of symptoms or duration. Paroxysmal AF occurs when a patient has 2 or more self-terminating episodes lasting less than 7 days. Persistent AF refers to episodes lasting more than 7 days that do not self-terminate. Permanent AF is continuous atrial fibrillation that cannot be cardioverted or if attempts to do so are deemed inappropriate. The treatment goals for permanent AF are rate control and anticoagulation if appropriate.

Symptoms of AF include palpitations, dyspnea, and chest pain. The most common sign is an irregularly irregular pulse. An electrocardiogram (ECG) is essential for diagnosing AF, as other conditions can also cause an irregular pulse.

Managing patients with AF involves two key parts: rate/rhythm control and reducing stroke risk. Rate control involves slowing down the irregular pulse to avoid negative effects on cardiac function. This is typically achieved using beta-blockers or rate-limiting calcium channel blockers. If one drug is not effective, combination therapy may be used. Rhythm control aims to restore and maintain normal sinus rhythm through pharmacological or electrical cardioversion. However, the majority of patients are managed with a rate control strategy.

Reducing stroke risk in patients with AF is crucial. Risk stratifying tools, such as the CHA2DS2-VASc score, are used to determine the most appropriate anticoagulation strategy. Anticoagulation is recommended for patients with a score of 2 or more. Clinicians can choose between warfarin and novel oral anticoagulants (NOACs) for anticoagulation.

Before starting anticoagulation, the patient’s bleeding risk should be assessed using tools like the HAS-BLED score or the ORBIT tool. These tools evaluate factors such as hypertension, abnormal renal or liver function, history of bleeding, age, and use of drugs that predispose to bleeding.

Wolff-Parkinson-White (WPW) syndrome is a condition that affects the electrical system of the heart. It occurs when there is an abnormal pathway, known as the bundle of Kent, between the atria and the ventricles. This pathway can cause premature contractions of the ventricles, leading to a type of rapid heartbeat called atrioventricular re-entrant tachycardia (AVRT).

In a normal heart rhythm, the electrical signals travel through the bundle of Kent and stimulate the ventricles. However, in WPW syndrome, these signals can cause the ventricles to contract prematurely. This can be seen on an electrocardiogram (ECG) as a shortened PR interval, a slurring of the initial rise in the QRS complex (known as a delta wave), and a widening of the QRS complex.

There are two distinct types of WPW syndrome that can be identified on an ECG. Type A is characterized by predominantly positive delta waves and QRS complexes in the praecordial leads, with a dominant R wave in V1. This can sometimes be mistaken for right bundle branch block (RBBB). Type B, on the other hand, shows predominantly negative delta waves and QRS complexes in leads V1 and V2, and positive in the other praecordial leads, resembling left bundle branch block (LBBB).

Overall, WPW syndrome is a condition that affects the electrical conduction system of the heart, leading to abnormal heart rhythms. It can be identified on an ECG by specific features such as shortened PR interval, delta waves, and widened QRS complex.

Atropine is a medication that slows down the movement of the digestive system and is not recommended for use in individuals with intestinal blockage. It works by blocking the effects of a neurotransmitter called acetylcholine, which is responsible for promoting gastrointestinal motility and the emptying of the stomach. Therefore, atropine should not be given to patients with gastrointestinal obstruction as it can further hinder the movement of the intestines.

Further Reading:

Types of Heart Block:

1. Atrioventricular (AV) Blocks:
– Disrupt electrical conduction between the atria and ventricles at the AV node.
– Three degrees of AV block: first degree, second degree (type 1 and type 2), and third degree (complete) AV block.

– First degree AV block: PR interval > 0.2 seconds.
– Second degree AV block:
– Type 1 (Mobitz I, Wenckebach): progressive prolongation of the PR interval until a dropped beat occurs.
– Type 2 (Mobitz II): PR interval is constant, but the P wave is often not followed by a QRS complex.
– Third degree (complete) AV block: no association between the P waves and QRS complexes.

Features of complete heart block: syncope, heart failure, regular bradycardia (30-50 bpm), wide pulse pressure, JVP (jugular venous pressure) cannon waves in neck, variable intensity of S1.

2. Bundle Branch Blocks:
– Electrical conduction travels from the bundle of His to the left and right bundle branches.
– Diagnosed when the duration of the QRS complex on the ECG exceeds 120 ms.

– Right bundle branch block (RBBB).
– Left bundle branch block (LBBB).
– Left anterior fascicular block (LAFB).
– Left posterior fascicular block (LPFB).
– Bifascicular block.
– Trifascicular block.

ECG features of bundle branch blocks:
– RBBB: QRS duration > 120 ms, RSR’ pattern in V1-3 (M-shaped QRS complex), wide S wave in lateral leads (I, aVL, V5-6).
– LBBB: QRS duration > 120 ms, dominant S wave in V1, broad, notched (‘M’-shaped) R wave in V6, broad monophasic R wave in lateral leads (I, aVL, V5-6), absence of Q waves in lateral leads, prolonged R wave peak time > 60 ms in leads V5-6.

WiLLiaM MaRROW is a useful mnemonic for remembering the morphology of the QRS in leads V1 and V6 for LBBB.

Adrenaline should be administered promptly once access to the circulatory system has been established in cases of non-shockable cardiac arrests such as PEA or asystole. The recommended dose is 1 mg, which can be given either as 10 mL of a 1:10,000 solution or as 1 mL of a 1:1000 solution through the intravenous (IV) or intraosseous (IO) routes.

In cases of shockable cardiac arrests like ventricular fibrillation (Vf) or pulseless ventricular tachycardia (pVT), adrenaline should be administered after the third shock has been delivered and chest compressions have been resumed. The same dose of 1 mg can be given using the same concentration options as mentioned earlier.

Subsequently, adrenaline should be administered every 3-5 minutes, alternating with chest compressions, without interrupting the compressions. The alpha-adrenergic effects of adrenaline cause constriction of blood vessels throughout the body, leading to increased pressures in the coronary and cerebral circulation.

The beta-adrenergic effects of adrenaline have positive effects on the heart, increasing its contractility (inotropic) and heart rate (chronotropic), which may also enhance blood flow to the coronary and cerebral arteries. However, it is important to note that these benefits may be counteracted by increased oxygen consumption by the heart, the potential for abnormal heart rhythms, temporary decrease in oxygen levels due to abnormal blood flow in the lungs, impaired microcirculation, and increased dysfunction of the heart after the cardiac arrest.

While there is no evidence supporting the long-term benefits of adrenaline use in cardiac arrest cases, some studies have shown improved short-term survival rates, which justifies its continued use.

The ECG shows the following findings:
– There is ST depression in leads V1-V4 and aVR.
– There is ST elevation in leads V5-V6, II, III, and aVF.
– There is a positive R wave in leads V1 and V2, which indicates a reverse Q wave.
These ECG changes indicate that there is an acute inferoposterior myocardial infarction.