Common Heart Murmurs and their Association with Rheumatic Heart Disease

Rheumatic heart disease (RHD) is a condition resulting from untreated pharyngitis caused by group A beta-haemolytic streptococcal infection. RHD can lead to heart valve dysfunction, most commonly the mitral valve, resulting in mitral stenosis. The characteristic murmur of mitral stenosis is a mid-diastolic rumbling murmur that follows an opening snap after S2. Aortic stenosis can also be present in RHD but is less prevalent. Other heart murmurs associated with RHD include a high-pitched blowing diastolic decrescendo murmur, which is associated with aortic regurgitation, and a continuous machine-like murmur that is loudest at S2, consistent with patent ductus arteriosus. A late systolic crescendo murmur with a mid-systolic click is seen in mitral valve prolapse. A crescendo-decrescendo systolic ejection murmur following an ejection click describes the murmur heard in aortic stenosis. It is important to recognize these murmurs and their association with RHD for proper diagnosis and management.

Diagnosis of Aortic Stenosis

There is a significant difference in pressure (81 mmHg) between the left ventricle and the aortic valve, indicating a critical case of aortic stenosis. Although hypertrophic obstructive cardiomyopathy (HOCM) can also cause similar pressure differences, the patient’s age and clinical information suggest that aortic stenosis is more likely.

To determine the severity of aortic stenosis, the valve area and mean gradient are measured. A valve area greater than 1.5 cm2 and a mean gradient less than 25 mmHg indicate mild aortic stenosis. A valve area between 1.0-1.5 cm2 and a mean gradient between 25-50 mmHg indicate moderate aortic stenosis. A valve area less than 1.0 cm2 and a mean gradient greater than 50 mmHg indicate severe aortic stenosis. A valve area less than 0.7 cm2 and a mean gradient greater than 80 mmHg indicate critical aortic stenosis.

Common Congenital Heart Defects and their Characteristics

An endocardial cushion defect, also known as an AVSD, is the most prevalent cardiac malformation in individuals with Down Syndrome. This defect can lead to irreversible pulmonary hypertension, which is known as Eisenmenger’s syndrome. It is unclear why children with Down Syndrome tend to have more severe cardiac disease than unaffected children with the same abnormality.

ASDs, or atrial septal defects, may close on their own, and the likelihood of spontaneous closure is related to the size of the defect. If the defect is between 5-8 mm, there is an 80% chance of closure, but if it is larger than 8 mm, the chance of closure is minimal.

Tetralogy of Fallot, a cyanotic congenital heart disease, typically presents after three months of age. The murmur of VSD, or ventricular septal defect, becomes more pronounced after one month of life. Overall, the characteristics of these common congenital heart defects is crucial for proper diagnosis and treatment.

Anatomy of the Heart: Intercostal Spaces and Auscultation Positions

The human heart is a vital organ responsible for pumping blood throughout the body. Understanding its anatomy is crucial for medical professionals to diagnose and treat various heart conditions. In this article, we will discuss the intercostal spaces and auscultation positions related to the heart.

Left Fifth Intercostal Space: Apex of the Heart
The apex of the heart is located deep to the left fifth intercostal space, approximately 8-9 cm from the mid-sternal line. This is an important landmark for cardiac examination and procedures.

Left Fourth Intercostal Space: Left Ventricle
The left ventricle, one of the four chambers of the heart, is located superior to the apex and can be auscultated in the left fourth intercostal space.

Right Fourth Intercostal Space: Right Atrium
The right atrium, another chamber of the heart, is located immediately lateral to the right sternal margin at the right fourth intercostal space.

Left Second Intercostal Space: Pulmonary Valve
The pulmonary valve, which regulates blood flow from the right ventricle to the lungs, can be auscultated in the left second intercostal space, immediately lateral to the left sternal margin.

Right Fifth Intercostal Space: Incorrect Location
The right fifth intercostal space is an incorrect location for cardiac examination because the apex of the heart is located on the left side.

In conclusion, understanding the intercostal spaces and auscultation positions related to the heart is essential for medical professionals to accurately diagnose and treat various heart conditions.

Understanding Pacemaker Coding and Indications

Pacemakers are electronic devices that are implanted in the chest to regulate the heartbeat. They are used to treat a variety of heart conditions, including sinus node dysfunction, atrial fibrillation (AF), and heart block. Pacemakers are coded based on the chambers they pace, sense, and respond to, as well as their ability to modulate heart rate and provide multisite pacing.

AAI pacemakers are used to pace the atria in patients with sinus node dysfunction and intact AV conduction. VVI pacemakers are used in patients with chronic atrial impairment, such as AF. DDD pacemakers are used to pace both the atria and ventricles in patients with second-degree heart block.

It is important to note that AAI pacemakers would not be effective in treating ventricular systolic dysfunction, and DDD pacemakers cannot be used in the treatment of long QT syndrome. However, pacemakers can be used in long QT syndrome if clinically necessary, and DDD pacing may be appropriate for some patients with first-degree heart block.

In summary, understanding pacemaker coding and indications is crucial for selecting the appropriate device for each patient’s unique heart condition.

During embryonic development, the septum primum grows down from the roof of the primitive atrium and fuses with the endocardial cushions. It initially has a hole called the ostium primum, which closes as the septum grows downwards. However, a second hole called the ostium secundum develops in the septum primum before fusion can occur. The septum secundum then grows downwards and to the right of the septum primum and ostium secundum. The foramen ovale is a passage through the septum secundum that allows blood to shunt from the right to the left atrium in the fetus, bypassing the pulmonary circulation. This defect closes at birth due to a drop in pressure within the pulmonary circulation after the infant takes a breath. If there is overlap between the foramen ovale and ostium secundum or if the ostium primum fails to close, an atrial septal defect results. This defect does not cause cyanosis because oxygenated blood flows from left to right through the defect.

Treatment Options for a Patient with Hypercholesterolemia and Recent MI

When treating a patient with hypercholesterolemia and a recent myocardial infarction (MI), it is important to choose the most appropriate treatment option. In this case, high-dose atorvastatin is the best choice due to the patient’s high cholesterol levels and family history. It is crucial to note that medication should have been prescribed before the patient’s discharge.

While dietary advice can be helpful, it is not the most urgent treatment option. Ezetimibe would only be prescribed if a statin were contraindicated. In this high-risk patient, low-dose atorvastatin is not sufficient, and high-dose atorvastatin is required, provided it is tolerated. If cholesterol control does not improve with high-dose atorvastatin, ezetimibe can be added at a later check-up. Overall, the priority is to control the patient’s high cholesterol levels with medication.

Interpreting Chest X-Ray Findings in Heart Failure

Chest X-rays are commonly used to assess patients with heart failure. Here are some key findings to look out for:

– Patchy perihilar shadowing: This suggests alveolar oedema, which can arise due to fluid overload in heart failure. Intravenous fluids should be given slowly, with frequent re-assessment for signs of peripheral and pulmonary oedema.
– Cardiothoracic ratio of 0.5: A ratio of >0.5 on a postero-anterior (PA) chest X-ray may indicate heart failure. A ratio of 0.5 or less is considered normal.
– Patchy shadowing in lower zones: This may suggest consolidation caused by pneumonia, which can complicate heart failure.
– Prominent lower zone vessels: In pulmonary venous hypertension, there is redistribution of blood flow to the non-dependent upper lung zones, leading to larger vessels in the lower zones.
– Narrowing of the carina: This may suggest enlargement of the left atrium, which sits directly under the carina in the chest.

For the management of heart failure, first line options include ACE inhibitors, beta-blockers, and aldosterone antagonists. In this case, the patient was already on a beta-blocker and an ACE inhibitor which had been effective. The addition of an aldosterone antagonist such as spironolactone would be the best option as it prevents fluid retention and reduces pressure on the heart. Ivabradine is a specialist intervention that should only be considered after trying all other recommended options. Addition of furosemide would only provide symptomatic relief. Insertion of an implantable cardiac defibrillator device is a late-stage intervention. Encouraging regular exercise and a healthy diet is important but does not directly address the patient’s clinical deterioration.

Heart Failure Medications: Prognostic and Symptomatic Benefits

Heart failure is a prevalent disease that can be managed with various medications. These medications can be divided into two categories: those with prognostic benefits and those with symptomatic benefits. Prognostic medications help improve long-term outcomes, while symptomatic medications provide relief from symptoms.

Prognostic medications include selective beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II antagonists, and spironolactone. In the RALES trial, spironolactone was shown to reduce all-cause mortality by 30% in patients with heart failure and an ejection fraction of less than 35%.

Symptomatic medications include loop diuretics, digoxin, and vasodilators such as nitrates and hydralazine. These medications provide relief from symptoms but do not improve long-term outcomes.

Other medications, such as nifedipine, sotalol, and naftidrofuryl, are used to manage other conditions such as angina, hypertension, and peripheral and cerebrovascular disorders, but are not of prognostic benefit in heart failure.

Treatment for heart failure can be tailored to each individual case, and heart transplant remains a limited option for certain patient groups. Understanding the benefits and limitations of different medications can help healthcare providers make informed decisions about the best course of treatment for their patients.

The best medication for the patient in the scenario would be indapamide, a thiazide diuretic that blocks the Na+/Cl− cotransporter in the distal convoluted tubules, increasing calcium reabsorption and reducing the risk of osteoporotic fractures. Common side-effects include hyponatraemia, hypokalaemia, hypercalcaemia, hyperglycaemia, hyperuricaemia, gout, postural hypotension and hypochloraemic alkalosis.

Prazosin is used for benign prostatic hyperplasia.

Enalapril is not preferred for patients over 55 years old and can increase osteoporosis risk.

Propranolol is not a preferred initial treatment for hypertension, and amlodipine can cause ankle swelling and should be avoided in patients with myocardial infarction and symptomatic heart failure.

Types of Cardiomyopathy and Congenital Heart Defects

Cardiomyopathy is a group of heart diseases that affect the structure and function of the heart muscle. There are different types of cardiomyopathy, each with its own causes and symptoms. Additionally, there are congenital heart defects that can affect the heart’s structure and function from birth. Here are some of the most common types:

1. Hypertrophic cardiomyopathy: This is an inherited condition that causes the heart muscle to thicken, making it harder for the heart to pump blood. It can lead to sudden death in young athletes.

2. Restrictive cardiomyopathy: This is a rare form of cardiomyopathy that is caused by diseases that restrict the heart’s ability to fill with blood during diastole.

3. Dilated cardiomyopathy: This is the most common type of cardiomyopathy, which causes the heart chambers to enlarge and weaken, leading to heart failure.

4. Mitral stenosis: This is a narrowing of the mitral valve, which can impede blood flow between the left atrium and ventricle.

In addition to these types of cardiomyopathy, there are also congenital heart defects, such as ventricular septal defect, which is the most common congenital heart defect. This condition creates a direct connection between the right and left ventricles, affecting the heart’s ability to pump blood effectively.

Understanding the different types of cardiomyopathy and congenital heart defects is important for proper diagnosis and treatment. If you experience symptoms such as chest pain, shortness of breath, or fatigue, it is important to seek medical attention promptly.

Effects of Atrial Fibrillation on the Heart

Atrial fibrillation is a condition characterized by irregular and rapid heartbeats. This condition can have several effects on the heart, including the following:

Fourth Heart Sound: In conditions such as hypertensive heart disease, active atrial contraction can cause active filling of a stiff left ventricle, leading to the fourth heart sound. However, this sound cannot be heard in atrial fibrillation.

Apical-Radial Pulse Deficit: Ineffective left ventricular filling can lead to cardiac ejections that cannot be detected by radial pulse palpation, resulting in the apical-radial pulse deficit.

Left Atrial Thrombus: Stasis of blood in the left atrial appendage due to ineffective contraction in atrial fibrillation is the main cause of systemic embolisation.

Reduction of Cardiac Output by 20%: Ineffective atrial contraction reduces left ventricular filling volumes, leading to a reduction in stroke volume and cardiac output by up to 20%.

Symptomatic Palpitations: Palpitations are the most common symptom reported by patients in atrial fibrillation.

Overall, atrial fibrillation can have significant effects on the heart and may require medical intervention to manage symptoms and prevent complications.

Common Factors Affecting Blood Pressure Readings

Blood pressure readings can be affected by various factors, including cuff size, alcohol and caffeine consumption, white coat hypertension, pain, and more. It is important to be aware of these factors to ensure accurate readings.

Incorrect Cuff Size:
Using a cuff that is too large can result in an underestimation of blood pressure, while a cuff that is too small can cause a falsely elevated reading.

Alcohol and Caffeine:
Both alcohol and caffeine can cause a temporary increase in blood pressure.

White Coat Hypertension:
Many patients experience elevated blood pressure in medical settings due to anxiety. To obtain an accurate reading, blood pressure should be measured repeatedly on separate occasions.

Pain:
Pain is a common cause of blood pressure increase and should be taken into consideration during medical procedures. A significant rise in blood pressure during a procedure may indicate inadequate anesthesia.

Factors Affecting Blood Pressure Readings

The cardiovascular system relies on a complex network of hormones and signaling molecules to regulate blood pressure, fluid balance, and other physiological processes. Here are some key players in this system:

B-type natriuretic peptide (BNP): This hormone is secreted by the ventricle in response to stretch, and levels are elevated in heart failure.

Angiotensin II: This hormone is produced mostly in the lungs where angiotensin-converting enzyme (ACE) concentrations are maximal.

C-type natriuretic peptide: This signaling molecule is produced by the endothelium, and not the heart.

Nitric oxide: This gasotransmitter is released tonically from all endothelial lined surfaces, including the heart, in response to both flow and various agonist stimuli.

Renin: This enzyme is released from the kidney, in response to reductions in blood pressure, increased renal sympathetic activity or reduced sodium and chloride delivery to the juxtaglomerular apparatus.

Understanding the roles of these hormones and signaling molecules is crucial for managing cardiovascular health and treating conditions like heart failure.

Treatment Options for ST Elevation Myocardial Infarction (STEMI)

When a patient presents with a ST elevation myocardial infarction (STEMI), prompt and appropriate treatment is crucial. The gold standard treatment for a STEMI is a primary percutaneous coronary intervention (PCI), which should be performed as soon as possible. In the absence of contraindications, all patients should receive aspirin, ticagrelor, and low-molecular-weight heparin before undergoing PCI.

Delaying PCI by treating the pain with sublingual glyceryl trinitrate (GTN), aspirin, and oxygen, and reviewing the patient in 15 minutes is not recommended. Similarly, giving the patient aspirin, ticagrelor, and low molecular weight heparin without performing PCI is incomplete management.

Thrombolysis therapy can be performed on patients without access to primary PCI. However, if primary PCI is available, it is the preferred treatment option.

It is important to note that waiting for cardiac enzymes is not recommended as it would only result in a delay in definitive management. Early and appropriate treatment is crucial in improving outcomes for patients with STEMI.

Electrocardiogram Changes and Symptoms Associated with Electrolyte Imbalances

Electrolyte imbalances can cause various changes in the electrocardiogram (ECG) and present with specific symptoms. Here are some of the common electrolyte imbalances and their associated ECG changes and symptoms:

Hypokalaemia:
– ECG changes: small T-waves, ST depression, prolonged QT interval, prominent U-waves
– Symptoms: generalised weakness, lack of energy, muscle pain, constipation
– Treatment: potassium replacement with iv infusion of potassium chloride (rate of infusion should not exceed 10 mmol of potassium an hour)

Hyponatraemia:
– ECG changes: ST elevation
– Symptoms: headaches, nausea, vomiting, lethargy
– Treatment: depends on the underlying cause

Hypocalcaemia:
– ECG changes: prolongation of the QT interval
– Symptoms: paraesthesia, muscle cramps, tetany
– Treatment: calcium replacement

Hyperkalaemia:
– ECG changes: tall tented T-waves, widened QRS, absent P-waves, sine wave appearance
– Symptoms: weakness, fatigue
– Treatment: depends on the severity of hyperkalaemia

Hypercalcaemia:
– ECG changes: shortening of the QT interval
– Symptoms: moans (nausea, constipation), stones (kidney stones, flank pain), groans (confusion, depression), bones (bone pain)
– Treatment: depends on the underlying cause

It is important to recognise and treat electrolyte imbalances promptly to prevent complications.

Cardiac Signs and Their Associated Conditions

Corrigan’s Sign: This sign is characterized by an abrupt distension and collapse of the carotid arteries, indicating aortic incompetence. It is often seen in patients with a collapsing pulse and an early diastolic murmur, which are suggestive of aortic regurgitation. A wide pulse pressure may also be found.

Malar Flush: Mitral stenosis is associated with malar flush, a mid-diastolic murmur, loudest at the apex when the patient is in the left lateral position, and a tapping apex. A small-volume pulse is also typical.

Tapping Apex: A tapping apex is a classical sign of mitral stenosis.

Pulsatile Hepatomegaly: Severe tricuspid regurgitation can cause reverse blood flow to the liver during systole, resulting in pulsatile hepatomegaly.

Clubbing: Clubbing is more commonly seen in lung pathology and is unlikely to present in aortic regurgitation. It is seen in congenital cyanotic heart disease.

Diagnostic Tests for Secondary Hypertension: Assessing the Causes

Secondary hypertension is a condition where high blood pressure is caused by an underlying medical condition. To diagnose the cause of secondary hypertension, various diagnostic tests are available. Here are some of the tests that can be done:

Magnetic Resonance Imaging with Gadolinium Contrast of Renal Arteries
This test is used to diagnose renal artery stenosis, which is the most common cause of secondary hypertension in young people, especially young women. It is done when a renal bruit is detected. Fibromuscular dysplasia, a vascular disorder that affects the renal arteries, is one of the most common causes of renal artery stenosis in young adults, particularly women.

Echocardiogram
While an echocardiogram can assess for end-organ damage resulting from hypertension, it cannot provide the actual cause of hypertension. Coarctation of the aorta is unlikely if there is no blood pressure differential between arms.

24-Hour Urine Cortisol
This test is done to diagnose Cushing syndrome, which is unlikely in this case. The most common cause of Cushing syndrome is exogenous steroid use, which the patient does not have. In addition, the patient has a normal BMI and does not have a cushingoid appearance on examination.

Plasma Metanephrines
This test is done to diagnose phaeochromocytoma, which is unlikely in this case. The patient does not have symptoms suggestive of it, such as sweating, headache, palpitations, and syncope. Phaeochromocytoma is also a rare tumour, causing less than 1% of cases of secondary hypertension.

Renal Ultrasound
This test is a less accurate method for assessing the renal arteries. Renal parenchymal disease is unlikely in this case as urinalysis, urea, and creatinine are normal.

Diagnostic Tests for Secondary Hypertension: Assessing the Causes

Diagnostic Investigations for Cardiac Conditions

When a patient presents with signs and symptoms of a cardiac condition, various diagnostic investigations may be performed to determine the underlying cause. In the case of a patient with chest tightness, the first-line investigation is usually an electrocardiogram (ECG) to rule out acute coronary syndrome. However, if the patient is suspected of having aortic stenosis (AS), the best diagnostic investigation is an echocardiogram and Doppler to measure the size of the aortic valve. A normal aortic valve area is more than 2 cm2, while severe AS is defined as less than 1 cm2.

Other diagnostic investigations for cardiac conditions include a coronary angiogram to assess the patency of the coronary arteries and potentially perform an angioplasty to insert a stent if any narrowing is found. Exercise tolerance tests can also be useful in monitoring patients with a cardiac history and heart failure classification. However, a D-dimer test, which is used to diagnose pulmonary embolism, would not be indicated in a patient with suspected AS unless there were additional features suggestive of a pulmonary embolism, such as calf tenderness.

Differential Diagnosis for a Patient with Vasovagal Syncope

Vasovagal syncope is a common cause of transient loss of consciousness. The hallmark of this condition is the three Ps – pallor, palpitations, and sweating. In patients with a history of vasovagal syncope, the ECG is typically normal. A prolonged PR interval may be seen in young athletes, but first-degree heart block rarely causes cardiac syncope. Ischemic heart disease is not a significant factor in this condition, and a family history of myocardial infarction is not relevant.

If there are no features suggesting a more serious cause of transient loss of consciousness or a significant personal or family cardiac history, the patient can be discharged from the Emergency Department. However, they should be advised to seek medical attention if they experience any further episodes.

Other conditions that may cause transient loss of consciousness include complete heart block, hypertrophic cardiomyopathy, substance misuse, and long QT syndrome. However, in this case, the patient’s history and ECG are not suggestive of these conditions.

Understanding the Electrocardiogram: Key Components and Timing

As a junior doctor, interpreting electrocardiograms (ECGs) is a crucial skill. One important aspect to understand is the timing of key components. The QT interval, which measures ventricular depolarization and repolarization, gives an indication of the duration of ventricular systole. However, this measurement is dependent on heart rate and is corrected using Bazett’s formula. The P wave results from atrial depolarization, while the QRS complex is caused by ventricular depolarization. The first heart sound, which coincides with the QRS complex, results from closure of the AV valves as the ventricles contract. The second heart sound, occurring at about the same time as the T wave, is caused by closure of the aortic and pulmonary valves. Understanding the timing of these components is essential for accurate ECG interpretation.

Ageing and Cardiovascular Health: Understanding the Normal and Abnormal Changes

As we age, our organs may still function normally at rest, but they may struggle to respond adequately to stressors such as exercise or illness. One of the key indicators of cardiovascular health is VO2 max, which measures the maximum rate of oxygen consumption during exercise. In normal ageing, VO2 max may decrease along with muscle strength, making intense exertion more difficult. However, significantly reduced VO2 max, left ventricular ejection fraction (LVEF), or stroke volume are not consistent with normal ageing. Additionally, hypotension or hypertension are not typical changes associated with ageing. Understanding these normal and abnormal changes can help us better monitor and manage our cardiovascular health as we age.

Distinguishing Pericarditis from Other Cardiac Conditions: A Clinical Overview

Pericarditis is a common cause of widespread ST elevation, characterized by chest pain that is often pleuritic and relieved by sitting forwards. Other symptoms include dry cough, dyspnoea, and flu-like symptoms, with the most important sign being pericardial rub. It can be caused by viral infections, post-MI, tuberculosis, or uraemia.

While pulmonary embolism may cause similar pleuritic pain, it would not result in the same ECG changes as pericarditis. Acute MI causes ST elevation in the affected coronary artery territory, with reciprocal ST depression. Hypertrophic cardiomyopathy presents with syncope or pre-syncope, and ECG changes consistent with left ventricular and septal hypertrophy. Ventricular aneurysm is another cause of ST elevation, but the clinical scenario and patient age align with a diagnosis of acute pericarditis.

In summary, recognizing the unique clinical presentation and ECG changes of pericarditis is crucial in distinguishing it from other cardiac conditions.

Appropriate Management for a Patient with Unstable Angina

Unstable angina is a serious condition that requires urgent medical attention. In the case of a patient displaying textbook signs of unstable angina, such as crushing chest pain occurring at rest, admission to the hospital is necessary. Sending the patient home with only glyceryl trinitrate (GTN) spray is not appropriate, as the patient is at high risk of having a myocardial infarction (MI). Instead, the patient should be seen by Cardiology for consideration of an urgent elective angiogram.

Prescribing ramipril and simvastatin is not indicated unless there is evidence of hypertension. Lifestyle advice, including exercise recommendation, is also not appropriate for a patient with unstable angina. The immediate problem should be addressed first, which is the need for an angiogram.

It is important to differentiate between unstable and stable angina. Unstable angina presents with symptoms at rest, indicating a significant worsening of the patient’s cardiac disease. On the other hand, stable angina only presents with symptoms on exertion.

Sending the patient for percutaneous coronary intervention (PCI) is not necessary unless there is evidence of an MI. The pain experienced due to angina will alleviate itself most commonly at rest, unless the angina is unstable. Therefore, an urgent elective angiogram is the appropriate management for a patient with unstable angina.

The patient is experiencing cardiac tamponade, which is caused by fluid in the pericardial sac compressing the heart and reducing ventricular filling. This is likely due to pericarditis caused by recent radiotherapy. Beck’s triad of low blood pressure, raised JVP, and muffled heart sounds are indicative of tamponade. Urgent pericardiocentesis is necessary to aspirate the pericardial fluid, preferably under echocardiographic guidance. A fluid challenge with sodium chloride is not recommended as it may worsen the pericardial fluid. Ibuprofen is not effective in severe cases of pericardial effusion. GTN spray, morphine, clopidogrel, and aspirin are useful in managing myocardial infarction, which is a differential diagnosis to rule out. LMWH is not appropriate for tamponade and may worsen the condition if caused by haemopericardium.

Auscultation of Heart Valves: Locations and Sounds

The human heart has four valves that regulate blood flow. These valves can be heard through auscultation, a medical technique that involves listening to the sounds produced by the heart using a stethoscope. Here are the locations and sounds of each valve:

Tricuspid Valve: This valve is located on the right side of the heart and can be heard at the left sternal border in the fourth intercostal space. The sound produced by this valve is a low-pitched, rumbling noise.

Aortic Valve: The aortic valve is located on the left side of the heart and can be heard over the right sternal border at the second intercostal space. The sound produced by this valve is a high-pitched, clicking noise.

Pulmonary Valve: This valve is located on the right side of the heart and can be heard over the left sternal border at the second intercostal space. The sound produced by this valve is a high-pitched, clicking noise.

Thebesian Valve: The Thebesian valve is located in the coronary sinus and its closure cannot be auscultated.

Mitral Valve: This valve is located on the left side of the heart and can be heard by listening at the apex, in the left mid-clavicular line in the fifth intercostal space. The sound produced by this valve is a low-pitched, rumbling noise.

In summary, auscultation of heart valves is an important diagnostic tool that can help healthcare professionals identify potential heart problems. By knowing the locations and sounds of each valve, healthcare professionals can accurately diagnose and treat heart conditions.

Understanding ECG Time Measurements

When reading an electrocardiogram (ECG), it is important to understand the time measurements represented on the grid paper. The horizontal axis of the ECG represents time, with each small square measuring 1 mm in length and representing 40 milliseconds (0.04 seconds). A large square on the ECG grid has a length of 5 mm and represents 0.2 seconds. Five large squares covering a length of 25 mm on the grid represent 1 second of time. It is important to note that each small square has a length of 1 mm and equates to 40 milliseconds, not 4 seconds. Understanding these time measurements is crucial for accurately interpreting an ECG.

Differentiating Heart Murmurs: A Guide

Heart murmurs are abnormal sounds heard during a heartbeat and can indicate underlying heart conditions. Here is a guide to differentiating some common heart murmurs:

Tricuspid Regurgitation (TR)
TR presents with a loud pan-systolic murmur audible throughout the chest, often loudest in the tricuspid area. The most common cause is heart failure, with regurgitation being functional due to myocardial dilation. Patients may have raised JVPs, distended neck veins, and signs of right-sided heart failure.

Aortic Sclerosis
Aortic sclerosis is a loud murmur early in systole, with normal S1 and S2. It does not affect pulse pressure, and there is no radiation to the right carotid artery. Right-sided murmurs are louder on inspiration.

Aortic Stenosis
Aortic stenosis is a mid-systolic ejection murmur, heard best over the aortic area or right second intercostal space, with radiation into the right carotid artery. It may reduce pulse pressure to <40 mmHg, and S2 may be diminished. Pulmonary Stenosis
Pulmonary stenosis gives a crescendo-decrescendo ejection systolic murmur, loudest over the pulmonary area. It is not pan-systolic, and S2 splitting is widened due to prolonged pulmonic ejection.

Mitral Regurgitation
Mitral regurgitation is a pan-systolic murmur heard best over the mitral area, radiating to the axilla. It is not increased on inspiration.

Remember to listen carefully to S1 and S2, check for radiation, and consider associated symptoms to differentiate heart murmurs.

Relative and Absolute Contraindications to Thrombolysis

Thrombolysis is a treatment option for patients with ongoing cardiac ischemia and presentation within 12 hours of onset of pain. However, there are both relative and absolute contraindications to this treatment.

Absolute contraindications include internal or heavy PV bleeding, acute pancreatitis or severe liver disease, esophageal varices, active lung disease with cavitation, recent trauma or surgery within the past 2 weeks, severe hypertension (>200/120 mmHg), suspected aortic dissection, recent hemorrhagic stroke, cerebral neoplasm, and previous allergic reaction.

Relative contraindications include prolonged CPR, history of CVA, bleeding diathesis, anticoagulation, blood pressure of 180/100 mmHg, peptic ulcer, and pregnancy or recent delivery.

It is important to consider these contraindications before administering thrombolysis as they can increase the risk of complications. Primary percutaneous coronary intervention is the preferred treatment option, but if not available, thrombolysis can be a viable alternative. The benefit of thrombolysis decreases over time, and a target time of <30 minutes from admission for commencement of thrombolysis is typically recommended.