A 25-year-old male presents with exertional chest pain, shortness of breath, and occasional episodes of fainting during physical activity. He reports a family history of sudden cardiac death in a close relative.
Examination
General Examination:
- Pulse: 75 beats per minute, regular rhythm
- Blood Pressure (BP): 130/85 mmHg
- Respiratory Rate (RR): 16 breaths per minute
- SpO2 (Oxygen Saturation): 98% on room air
Systemic Examination:
- Cardiovascular System (CVS):
- Heart Sounds: A harsh systolic murmur best heard at the left sternal border, which increases with the Valsalva maneuver and when standing.
- JVP (Jugular Venous Pressure): Normal
- Peripheral Pulses: Normal, no pulse deficit noted
- Respiratory System (RS):
- Breath Sounds: Clear with no wheezes or crackles
- Inspection and Palpation: No significant findings
- Abdomen (PA – Per Abdominal):
- Liver and Spleen: Not palpable, no tenderness
- Ascites: Absent
- Bowel Sounds: Normal
- Central Nervous System (CNS):
- Mental Status: Alert and oriented
- Cranial Nerves, Motor, and Sensory Examination: Normal findings, no neurological deficits
ECG Findings
The ECG shows:
- Left ventricular hypertrophy (LVH) with a deep S wave in V1 and a tall R wave in V5
- Deep Q waves in the inferior leads (II, III, aVF) and lateral leads (I, aVL, V5, V6)
- Left atrial enlargement
- Normal sinus rhythm without any arrhythmias noted at the time of examination
Laboratory Tests
The laboratory tests reveal:
- B-type natriuretic peptide (BNP): Elevated at 150 pg/mL (reference range: <100 pg/mL), indicating increased ventricular pressure
- Genetic testing: Positive for a mutation in the MYH7 gene, associated with HOCM
Diagnosis
The diagnosis of HOCM is confirmed by:
- Echocardiography: Showing significant asymmetric septal hypertrophy (septal thickness of 18 mm) and left ventricular outflow tract obstruction with a gradient of 60 mmHg.
- Cardiac MRI: Revealing extensive myocardial fibrosis in the hypertrophied septum.
Overview
Hypertrophic Obstructive Cardiomyopathy (HOCM) is a genetic condition characterized by the abnormal thickening of the heart muscle, particularly affecting the interventricular septum. This thickening can obstruct blood flow from the left ventricle to the aorta, leading to various cardiac symptoms and complications.
Cause
HOCM is primarily caused by genetic mutations that affect the proteins involved in the contraction of heart muscle cells. It is inherited in an autosomal dominant pattern, meaning that having just one copy of the mutated gene can cause the disorder.
Signs and Symptoms
- Dyspnea (shortness of breath)
- Chest pain
- Palpitations
- Syncope (fainting), especially during or after exercise
- Fatigue
- Heart murmur
Treatment
The treatment of HOCM aims to relieve symptoms, prevent complications, and reduce the risk of sudden cardiac death:
- Medications:
- Beta-blockers: Reduce heart rate and myocardial oxygen consumption.
- Calcium channel blockers: Improve symptoms by reducing myocardial contractility.
- Antiarrhythmics: Manage atrial fibrillation or other arrhythmias.
- Procedures:
- Septal myectomy: Surgical removal of a portion of the thickened septum to improve blood flow.
- Alcohol septal ablation: Minimally invasive procedure to reduce septal thickness using alcohol injection.
- Implantable Devices:
- Implantable cardioverter-defibrillator (ICD): Prevents sudden cardiac death in high-risk patients by treating life-threatening arrhythmias.
- Lifestyle Modifications:
- Avoiding strenuous exercise.
- Regular follow-ups with a cardiologist.
Conclusion
HOCM is a complex genetic condition that requires careful management and monitoring. With appropriate diagnosis and treatment, many individuals with HOCM can lead normal, active lives. However, due to the risk of sudden cardiac death, especially in young individuals, it is crucial to recognize and manage the condition promptly.
