What are the typical presenting symptoms and management of hypertrophic obstructive cardiomyopathy (HOCM)?

From the Guidelines

Hypertrophic obstructive cardiomyopathy (HOCM) typically presents with exertional dyspnea, chest pain, palpitations, syncope, and occasionally sudden cardiac death, and management focuses on symptom relief and preventing complications through both pharmacological and non-pharmacological approaches. The most common features of a patient presenting with HOCM include:

• Exertional dyspnea
• Chest pain
• Palpitations
• Syncope
• Fatigue
• Dizziness
• Heart failure symptoms These symptoms occur due to the asymmetric septal hypertrophy causing left ventricular outflow tract obstruction, which worsens during exertion when cardiac output demands increase 1.

Management of HOCM

Management of HOCM involves:

• First-line medications such as beta-blockers (e.g., metoprolol 25-100 mg twice daily or propranolol 10-40 mg three times daily) to reduce heart rate, contractility, and outflow obstruction 1
• Non-dihydropyridine calcium channel blockers like verapamil (120-480 mg daily in divided doses) as alternatives for those intolerant to beta-blockers
• Disopyramide (100-300 mg twice daily) may be added for persistent symptoms
• Avoiding dehydration, excessive alcohol, and strenuous exercise, particularly activities involving Valsalva maneuvers
• Invasive options such as septal myectomy or alcohol septal ablation for refractory symptoms
• Implantable cardioverter-defibrillators for patients at high risk of sudden cardiac death Regular cardiac screening of first-degree relatives is essential due to the genetic nature of HOCM, with autosomal dominant inheritance patterns in many cases 1.

Perioperative Management

In the perioperative period, it is essential to:

• Continue beta blockers and/or non-dihydropyridine calcium channel blockers without interruption
• Avoid hypovolemia and reduced preload, which can worsen LVOT obstruction
• Avoid hypotension and reduced afterload, which can worsen LVOT obstruction
• Avoid tachycardia to ensure adequate LV filling
• Use alpha-agonists, such as phenylephrine or vasopressin, to manage hypotension, rather than beta-agonists, which can worsen LVOT obstruction 1.

From the Research

Typical Presenting Symptoms of Hypertrophic Obstructive Cardiomyopathy (HOCM)

• Dyspnea (shortness of breath) 2, 3, 4, 5
• Chest pain 2, 6, 3, 4
• Palpitations 3, 4
• Syncope (fainting) 2, 6, 3, 4

Management of HOCM

• Drug therapy:
  • Beta-blockers to decrease the incidence of dyspnea, chest pain, and syncope 6
  • Calcium channel inhibitors to improve symptomatology and prognosis 6
  • Amiodarone as an antiarrhythmic drug in obstructive syndromes complicated by severe ventricular arrhythmias 6
• Surgery:
  • Septal myectomy to alleviate the intraventricular obstacle, correct mitral regurgitation, and increase left ventricular compliance 6, 4
  • Dual chamber sequential pacing to reduce the risk of sudden death and symptomatology in selected patients 6
• Septal reduction therapy (myectomy or alcohol septal ablation) for patients with severe symptoms related to ventricular obstruction 4
• Cardioverter-defibrillator implantation for patients at increased risk of sudden cardiac death 4
• Life-long anticoagulation after the first episode of atrial fibrillation 4