Hypertrophic Cardiomyopathy HCM Flashcards
What is hypertrophic cardiomyopathy (HCM)?
hypertrophic cardiomyopathy is a genetic condition characterised by abnormal thickening (hypertrophy) of the myocardium, often involving the interventricular septum.
What is the primary cause of hypertrophic cardiomyopathy?
hypertrophic cardiomyopathy is caused by mutations in genes encoding sarcomeric proteins, inherited in an autosomal dominant pattern.
How does hypertrophic cardiomyopathy affect cardiac function?
The hypertrophied myocardium leads to diastolic dysfunction, left ventricular outflow tract (LVOT) obstruction, and increased risk of arrhythmias.
What are the typical symptoms of hypertrophic cardiomyopathy?
Symptoms include chest pain, exertional dyspnoea, palpitations, syncope, and, in some cases, sudden cardiac death.
What are the risk factors for hypertrophic cardiomyopathy?
Family history of hypertrophic cardiomyopathy, genetic predisposition, and certain mutations in sarcomeric protein genes.
What is the pathophysiology of LVOT obstruction in hypertrophic cardiomyopathy?
LVOT obstruction occurs due to systolic anterior motion of the mitral valve, which impinges on the hypertrophied septum, obstructing blood flow.
How is hypertrophic cardiomyopathy diagnosed?
Diagnosis is based on clinical features, echocardiography, ECG, and genetic testing in some cases.
What are the common ECG findings in hypertrophic cardiomyopathy?
ECG may show left ventricular hypertrophy, deep T-wave inversions, ST-segment changes, and abnormal Q waves.
What is the role of echocardiography in hypertrophic cardiomyopathy?
Echocardiography assesses the degree and distribution of hypertrophy, presence of LVOT obstruction, and diastolic dysfunction.
What are the potential complications of hypertrophic cardiomyopathy?
Complications include sudden cardiac death, arrhythmias, heart failure, and thromboembolism.
What is the prevalence of hypertrophic cardiomyopathy?
hypertrophic cardiomyopathy is relatively common, affecting approximately 1 in 500 people in the general population.
How does hypertrophic cardiomyopathy increase the risk of sudden cardiac death (SCD)?
Sudden Cardiac Death in hypertrophic cardiomyopathy is often caused by ventricular arrhythmias or sudden haemodynamic collapse due to LVOT obstruction.
What are the red flags for Sudden Cardiac Death in patients with hypertrophic cardiomyopathy?
Family history of Sudden Cardiac Death, unexplained syncope, severe hypertrophy (>30 mm), and non-sustained ventricular tachycardia on Holter monitoring.
What are the differential diagnoses for hypertrophic cardiomyopathy?
Differential diagnoses include athletic heart syndrome, hypertensive heart disease, and aortic stenosis.
What are the medical management options for hypertrophic cardiomyopathy?
Medications include beta-blockers, calcium channel blockers (e.g., verapamil), and disopyramide to reduce symptoms and outflow obstruction.
What lifestyle modifications are recommended for hypertrophic cardiomyopathy patients?
Avoid strenuous exercise, maintain hydration, and avoid dehydration or vasodilators that can worsen LVOT obstruction.
What is the role of implantable cardioverter-defibrillators (ICDs) in hypertrophic cardiomyopathy?
ICDs are used for primary or secondary prevention of sudden cardiac death in high-risk patients.
When is septal myectomy indicated in hypertrophic cardiomyopathy?
Septal myectomy is considered in patients with severe left ventricular outflow tract (LVOT) obstruction and refractory symptoms despite medical therapy.
What is alcohol septal ablation, and when is it used?
Alcohol septal ablation is a minimally invasive procedure to reduce septal thickness, used as an alternative to surgical myectomy in some patients.
What are the key findings on physical examination in hypertrophic cardiomyopathy?
A harsh crescendo-decrescendo systolic murmur, best heard at the left sternal edge, which may increase with Valsalva manoeuvre.
How is the murmur of hypertrophic cardiomyopathy distinguished from aortic stenosis?
The murmur of hypertrophic cardiomyopathy increases with Valsalva or standing and decreases with squatting, while the murmur of aortic stenosis does not change similarly.
What are the recommendations for family screening in hypertrophic cardiomyopathy?
First-degree relatives should undergo genetic testing and/or echocardiography and ECG to screen for the condition.
How is diastolic dysfunction managed in hypertrophic cardiomyopathy?
Diastolic dysfunction is managed with medications that slow heart rate, such as beta-blockers or calcium channel blockers, to improve ventricular filling.
Why is early diagnosis of hypertrophic cardiomyopathy important?
Early diagnosis allows for risk stratification, lifestyle modifications, and appropriate interventions to prevent complications like Sudden Cardiac Death.
What is the prognosis of hypertrophic cardiomyopathy?
With appropriate management, many patients have a good prognosis, though the risk of complications like Sudden Cardiac Death requires careful monitoring.
