Lachmann test

After experiencing an inferior-wall MI, the most common cause of death within the first hour is a lethal arrhythmia, such as ventricular fibrillation. This can be caused by various factors, including ischaemia, toxic metabolites, or autonomic stimulation. If ventricular fibrillation occurs within the first 48 hours, it may be due to transient causes and not affect long-term prognosis. However, if it occurs after 48 hours, it is usually indicative of permanent dysfunction and associated with a worse long-term prognosis. Other complications that may occur after an acute MI include emboli from a left ventricular thrombus, cardiac tamponade, ruptured papillary muscle, and pericarditis. These complications typically occur at different time frames after the acute MI and present with different symptoms.

Lithium Exposure During Pregnancy Linked to Ebstein’s Anomaly

Exposure to lithium during pregnancy has been found to be linked to the development of Ebstein’s anomaly in newborns. Ebstein’s anomaly is a rare congenital heart defect that affects the tricuspid valve, which separates the right atrium and right ventricle of the heart. This condition can cause a range of symptoms, including shortness of breath, fatigue, and heart palpitations.

Studies have shown that women who take lithium during pregnancy are at an increased risk of having a child with Ebstein’s anomaly. Lithium is commonly used to treat bipolar disorder, and while it can be an effective treatment, it is important for women who are pregnant or planning to become pregnant to discuss the risks and benefits of taking lithium with their healthcare provider.

It is important for healthcare providers to be aware of the potential risks associated with lithium use during pregnancy and to closely monitor pregnant women who are taking this medication. Early detection and treatment of Ebstein’s anomaly can improve outcomes for affected infants.

ECG Changes and Localisation of Infarct in Coronary Artery Disease

Patients with chest pain and multiple risk factors for cardiac disease require prompt evaluation to determine the underlying cause. Electrocardiogram (ECG) changes can help localise the infarct to a particular territory, which can aid in diagnosis and treatment.

Inferior infarcts are often due to lesions in the right coronary artery, as evidenced by ST elevation in leads II, III, and aVF. However, in 20% of cases, this can also be caused by an occlusion of a dominant left circumflex artery.

Lateral infarcts involve branches of the left anterior descending (LAD) and left circumflex arteries, and are characterised by ST elevation in leads I, aVL, and V5-6. It is unusual for a lateral STEMI to occur in isolation, and it usually occurs as part of a larger territory infarction.

Anterior infarcts are caused by blockage of the LAD artery, and are characterised by ST elevation in leads V1-V6.

Blockage of the right marginal artery does not have a specific pattern of ECG changes associated with it, and it is not one of the major coronary vessels.

In summary, understanding the ECG changes associated with different coronary arteries can aid in localising the infarct and guiding appropriate treatment.

Differentiating Aortic and Mitral Valve Disorders

When evaluating a patient with a heart murmur, it is important to consider the characteristics of the murmur and associated symptoms to determine the underlying valve disorder. In a patient under 70 years old, a slow-rising and weak pulse with a history of collapse is indicative of critical stenosis caused by a bicuspid aortic valve. On the other hand, calcific aortic stenosis is more common in patients over 70 years old and presents differently. Aortic valve regurgitation is characterized by a murmur heard during early diastole and a collapsing pulse, but it is less likely to cause syncope. Mitral valve regurgitation causes a pan-systolic murmur at the apex with a laterally displaced apex beat, but it may present with congestive heart failure rather than syncope or angina. Mitral valve prolapse may cause a mid-systolic click, but a pan-systolic murmur at the apex may be present if there is coexisting mitral regurgitation. By understanding the unique features of each valve disorder, clinicians can make an accurate diagnosis and provide appropriate treatment.

Coronary Arteries and their Supply to Cardiac Conduction System

The heart’s conduction system is responsible for regulating the heartbeat. The following are the coronary arteries that supply blood to the different parts of the cardiac conduction system:

Sinoatrial Node
The sinoatrial node, which is the primary pacemaker of the heart, is supplied by the right coronary artery in 60% of cases through a sinoatrial nodal branch.

Atrioventricular Node
The atrioventricular node, which is responsible for delaying the electrical impulse before it reaches the ventricles, is supplied by the right coronary artery in 80% of individuals through the atrioventricular nodal branch.

Atrioventricular Bundle
The atrioventricular bundle, which conducts the electrical impulse from the atria to the ventricles, is supplied by numerous septal arteries that mostly arise from the anterior interventricular artery, a branch of the left coronary artery.

Left Bundle Branch
The left bundle branch, which conducts the electrical impulse to the left ventricle, is supplied by numerous subendocardial bundle arteries that originate from the left coronary artery.

Right Bundle Branch
The right bundle branch, which conducts the electrical impulse to the right ventricle, is supplied by numerous subendocardial bundle arteries that originate from the right coronary artery.

Cardiac Valve Disorders: Mitral Stenosis, Mitral Regurgitation, Aortic Regurgitation, Pulmonary Stenosis, and Primary Pulmonary Hypertension

Cardiac valve disorders are conditions that affect the proper functioning of the heart valves. Among these disorders are mitral stenosis, mitral regurgitation, aortic regurgitation, pulmonary stenosis, and primary pulmonary hypertension.

Mitral stenosis is a narrowing of the mitral valve, usually caused by rheumatic fever. Symptoms include palpitations, dyspnea, and hemoptysis. Diagnosis is aided by electrocardiogram, chest X-ray, and echocardiography. Management may be medical or surgical.

Mitral regurgitation is a systolic murmur that presents with a sustained apex beat displaced to the left and a left parasternal heave. On auscultation, there will be a soft S1, a loud S2, and a pansystolic murmur heard at the apex radiating to the left axilla.

Aortic regurgitation presents with a collapsing pulse with a wide pulse pressure. On palpation of the precordium, there will be a sustained and displaced apex beat with a soft S2 and an early diastolic murmur at the left sternal edge.

Pulmonary stenosis is associated with a normal pulse, with an ejection systolic murmur radiating to the lung fields. There may be a palpable thrill over the pulmonary area.

Primary pulmonary hypertension most commonly presents with progressive weakness and shortness of breath. There is evidence of an underlying cardiac disease, meaning the underlying pulmonary hypertension is more likely to be secondary to another disease process.

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.

This patient exhibits features of mixed mitral valve disease, which can be challenging to diagnose due to contradictory signs. She has a mid-diastolic rumble, low-volume pulse, and atrial fibrillation, indicating mitral stenosis. However, she also has a displaced apex beat and a pan-systolic murmur, indicating mitral regurgitation. Mixed aortic valve disease is also common in these patients. Aortic stenosis and mixed aortic valve disease are unlikely diagnoses based on the clinical findings, while mitral stenosis and mitral regurgitation alone do not fully explain the examination results.

Management of Cardiac Tamponade

Cardiac tamponade is a medical emergency that requires urgent intervention. The condition is characterized by a large amount of fluid in the pericardial sac, which can lead to compression of the heart and subsequent haemodynamic instability.

The first step in managing cardiac tamponade is to perform pericardiocentesis, which involves draining the fluid from the pericardial sac. Delaying this procedure can result in cardiac arrest and death.

While echocardiography can aid in diagnosis, it should not delay the initiation of pericardiocentesis. Similarly, a chest X-ray is not necessary for management. Swann-Ganz catheter insertion and inotropic support are also not recommended as they do not address the underlying cause of the condition.

In summary, prompt recognition and treatment of cardiac tamponade is crucial for patient survival.

Systolic Valvular Murmurs

A systolic valvular murmur can be caused by aortic/pulmonary stenosis or mitral/tricuspid regurgitation. It is important to note that the location where the murmur is heard loudest can be misleading. For instance, if it is aortic stenosis, the murmur is expected to radiate to the carotids. However, the significant factor to consider is that the murmur is heard loudest on inspiration. During inspiration, venous return to the heart increases, which exacerbates right-sided murmurs. Conversely, expiration reduces venous return and exacerbates left-sided murmurs. To remember this useful fact, the mnemonic RILE (Right on Inspiration, Left on Expiration) can be used.

If a systolic murmur is enhanced on inspiration, it must be a right-sided murmur, which could be pulmonary stenosis or tricuspid regurgitation. However, in this case, only pulmonary stenosis is an option. systolic valvular murmurs and their characteristics is crucial in making an accurate diagnosis and providing appropriate treatment.

Coarctation of the Aorta: Symptoms and Diagnosis

Coarctation of the aorta is a condition that can present with various symptoms. These may include headaches, nosebleeds, cold extremities, and claudication. However, hypertension is the most typical symptom. A mid-systolic murmur may also be present over the anterior part of the chest, back, spinous process, and a continuous murmur may also be heard.

One important radiographic finding in coarctation of the aorta is notching of the ribs. This is due to erosion by collaterals. It is important to diagnose coarctation of the aorta early on, as it can lead to serious complications such as heart failure, stroke, and aortic rupture.

Differentiating Pulmonary Oedema from Other Cardiac and Respiratory Conditions

Pulmonary oedema is a condition characterized by the accumulation of fluid in the lungs due to left ventricular failure. It presents with symptoms such as shortness of breath, raised jugular venous pressure, and a third heart sound. Bi-basal crackles are also a hallmark of pulmonary oedema. However, it is important to differentiate pulmonary oedema from other cardiac and respiratory conditions that may present with similar symptoms.

Tricuspid regurgitation is another cardiac condition that may present with a raised JVP and a third heart sound. However, it is characterized by additional symptoms such as ascites, a pulsatile liver, peripheral oedema, and a pansystolic murmur. Pneumonia, on the other hand, is a respiratory infection that presents with a productive cough of yellow or green sputum and shortness of breath. Bronchial breath sounds may also be heard upon auscultation.

Pulmonary embolus is a condition that presents with chest pain, shortness of breath, and signs of an underlying deep vein thrombosis. Pericardial effusion, on the other hand, is characterized by the accumulation of fluid in the pericardial sac surrounding the heart. It may eventually lead to cardiac tamponade, which presents with hypotension, shortness of breath, and distant heart sounds. However, bi-basal crackles are not a feature of pericardial effusion.

In summary, it is important to consider the specific symptoms and characteristics of each condition in order to accurately diagnose and differentiate pulmonary oedema from other cardiac and respiratory conditions.

Symptoms and Mortality Risk in Aortic Stenosis

Aortic stenosis is a serious condition that can lead to decreased cerebral perfusion and potentially fatal outcomes. Here are some common symptoms and their associated mortality risks:

– Syncope: This is a major concern and indicates the need for valve replacement, regardless of valve area.
– Chest pain: While angina can occur due to reduced diastolic coronary perfusion time and increased left ventricular mass, it is not as significant as syncope in predicting mortality.
– Cough: Aortic stenosis typically does not cause coughing.
– Palpitations: Unless confirmed to be non-sustained ventricular tachycardia, palpitations do not increase mortality risk.
– Orthostatic dizziness: Mild decreased cerebral perfusion can cause dizziness upon standing, but this symptom alone does not confer additional mortality risk.

It is important to be aware of these symptoms and seek medical attention if they occur, as aortic stenosis can be a life-threatening condition.

Differentiating Heart Murmurs: Causes and Characteristics

Heart murmurs are abnormal sounds heard during a heartbeat and can indicate underlying heart conditions. Here are some common causes and characteristics of heart murmurs:

Mitral Stenosis: This condition is most commonly caused by rheumatic fever in childhood and is rare in developed countries. Patients with mitral stenosis will have a loud S1 with an associated opening snap. However, if the mitral valve is calcified or there is severe stenosis, the opening snap may be absent and S1 soft.

Mitral Regurgitation and Ventricular Septal Defect: These conditions cause a pan-systolic murmur, which is not the correct option for differentiating heart murmurs.

Aortic Regurgitation: This condition leads to an early diastolic murmur.

Aortic Stenosis: Aortic stenosis causes an ejection systolic murmur.

Ventricular Septal Defect: As discussed, a ventricular septal defect will cause a pan-systolic murmur.

By understanding the causes and characteristics of different heart murmurs, healthcare professionals can better diagnose and treat underlying heart conditions.

Symptoms and Diagnosis of Infective Endocarditis

This individual has a lengthy medical history of experiencing night sweats and has developed clubbing of the fingers, along with a murmur. These symptoms are indicative of infective endocarditis. In addition to splinter hemorrhages in the nails, other symptoms that may be present include Roth spots in the eyes, Osler’s nodes and Janeway lesions in the palms and fingers of the hands, and splenomegaly instead of cervical lymphadenopathy. Cyanosis is not typically associated with clubbing and may suggest idiopathic pulmonary fibrosis or cystic fibrosis in younger individuals. However, this individual has no prior history of cystic fibrosis and has only been experiencing symptoms for six weeks.

Treatment Options for Atrial Fibrillation in a Patient with Heart Failure

When treating a patient with atrial fibrillation (AF) and heart failure, the aim should be rate control. While bisoprolol is a good choice, it may not be suitable for a patient with chronic low blood pressure. In this case, digoxin would be the treatment of choice. Anticoagulation with a NOAC or warfarin is also necessary. Cardioversion with amiodarone should not be the first line of treatment due to the patient’s heart failure. Increasing the dose of bisoprolol may not be the best option either. Amlodipine is not effective for rate control in AF, and calcium-channel blockers should not be used in heart failure. Electrical cardioversion is not appropriate for this patient. Overall, the treatment plan should be tailored to the patient’s individual needs and medical history.

Managing Atrial Fibrillation and Heart Failure: Treatment Options

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, it is important to consider both relative and absolute contraindications before administering thrombolysis.

Cerebral neoplasm is the only absolute contraindication, while advanced liver disease, severe hypertension (not meeting absolute contraindication values), active peptic ulceration, and pregnancy or recent delivery are all relative contraindications.

Primary PCI is the preferred treatment option if available, but thrombolysis can be used as an alternative if necessary. The benefit of thrombolysis decreases over time, and a target time of less than 30 minutes from admission is recommended. Thrombolysis should not be given if the onset of pain is more than 24 hours after presentation.

It is important to carefully consider contraindications before administering thrombolysis to ensure patient safety and optimal treatment outcomes.

Common Heart Murmurs and Their Associations

Heart murmurs are abnormal sounds heard during a heartbeat. They can be innocent or pathological, and their characteristics can provide clues to the underlying condition. Here are some common heart murmurs and their associations:

1. Ejection systolic murmur (ESM): This murmur is associated with aortic stenosis and is related to the ventricular outflow tract. It may be innocent in children and high-output states, but pathological causes include aortic stenosis and sclerosis, pulmonary stenosis, and hypertrophic obstructive cardiomyopathy.

2. Mid-diastolic murmur: This murmur is commonly associated with tricuspid or mitral stenosis and starts after the second heart sound and ends before the first heart sound. Rheumatic fever is a common cause of mitral valve stenosis.

3. Pansystolic murmur: This murmur is associated with mitral regurgitation and is of uniform intensity that starts immediately after S1 and merges with S2. It is also found in tricuspid regurgitation and ventricular septal defects.

4. Early diastolic murmur (EDM): This high-pitched murmur occurs in pulmonary and aortic regurgitation and is caused by blood flowing through a dysfunctional valve back into the ventricle. It may be accentuated by asking the patient to lean forward.

5. Continuous murmur: This murmur is commonly associated with a patent ductus arteriosus (PDA), a connection between the aorta and the pulmonary artery. It causes a continuous murmur, sometimes described as a machinery murmur, heard throughout both systole and diastole.

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.