What are the treatment options for Hypertrophic Obstructive Cardiomyopathy (HOCM)?

From the Guidelines

The treatment for Hypertrophic Obstructive Cardiomyopathy (HOCM) should prioritize beta-blockers as the first-line agent, with medications titrated to a dose where symptom benefit is observed, as recommended by the 2024 AHA/ACC/AMSSM/HRS/PACES/SCMR guideline 1.

Key Considerations

• Beta-blockers, such as metoprolol, are considered the first-line therapy for most patients with obstructive HCM, aiming to reduce heart rate, contractility, and outflow obstruction.
• For patients who do not respond to first-line therapy, cardiac myosin inhibitors like mavacamten may be considered, as they have been shown to improve LVOT gradients, symptoms, and functional capacity in patients with obstructive HCM 1.
• Invasive options, including septal reduction therapy through alcohol septal ablation or surgical myectomy, can provide safe and effective symptomatic relief for patients with drug-refractory or severe outflow tract obstruction, particularly when performed by experienced HCM teams at dedicated centers 1.
• Implantable cardioverter-defibrillators (ICDs) are recommended for patients at high risk of sudden cardiac death, and anticoagulation with direct oral anticoagulants or warfarin is indicated for patients with atrial fibrillation to prevent thromboembolism 1.

Management Approach

• The treatment approach should focus on reducing contractility, heart rate, and outflow tract obstruction, thereby improving filling dynamics and reducing myocardial oxygen demand.
• Patients should avoid dehydration, excessive alcohol, and activities that involve Valsalva maneuvers.
• Regular cardiology follow-up with echocardiography is essential to monitor disease progression and adjust treatment as needed.
• Shared decision-making between patients, families, and the care team is crucial in providing the best clinical care, considering the patient's personal preferences and goals 1.

From the FDA Drug Label

In 120 patients with hypertrophic cardiomyopathy (most of them refractory or intolerant to propranolol) who received therapy with verapamil at doses up to 720 mg/day, a variety of serious adverse effects were seen

• Treatment for HOCM: Verapamil can be used to treat patients with hypertrophic cardiomyopathy (HOCM) who are refractory or intolerant to propranolol, at doses up to 720 mg/day 2.
• Key considerations: Patients with severe left ventricular dysfunction or moderate to severe symptoms of cardiac failure should avoid verapamil, and those with milder ventricular dysfunction should be controlled with optimum doses of digitalis and/or diuretics before verapamil treatment 2.
• Adverse effects: Serious adverse effects, including pulmonary edema, severe hypotension, and AV block, have been reported in patients with HOCM treated with verapamil 2 2.

From the Research

Treatment Options for HOCM

• The treatment of HOCM encompasses activity restriction, prevention of sudden cardiac death, control of symptoms, and screening of relatives 3.
• Pharmacologic treatment of symptoms in patients with HOCM consists of negative inotropic drugs, namely beta blockers, and disopyramide; a nondihydropyridine calcium channel blocker (CCB), usually verapamil, may be used in patients with noncardiac side-effects of beta blockers 3.
• For patients with intolerable symptoms despite optimal conservative therapy, septal reduction therapy (SRT) should be considered and should be performed by experienced operators in institutions with multidisciplinary HCM programs 3.
• Younger patients with extreme hypertrophy are usually offered septal myectomy, while older patients, and those with important comorbidities are usually directed to alcohol septal ablation (ASA) 3.

Pharmacological Treatment

• In symptomatic patients with high LVOT gradients (≥ 50 mm Hg), the treatment of first choice is pharmacotherapy with nonvasodilating beta-blockers or non-dihydropyridine-type calcium channel antagonists 4.
• Beta-blockers alleviate dyspnea and improve patients' quality of life, while verapamil can increase physical resilience 4.
• Mavacamten, a myosin inhibitor, is a further option that lowers the LVOT gradient and improves quality of life 4.
• Disopyramide can be used as a rescue treatment in patients with obstructive hypertrophic cardiomyopathy refractory to beta blockers 5.

Surgical and Non-Surgical Septal Reduction Therapies

• Septal reduction treatments can be considered if drug therapy fails 4.
• Surgical myectomy and alcohol septal ablation are options for patients with symptomatic HOCM who do not respond to medical therapy 3, 6.
• The choice between surgical myectomy and alcohol septal ablation depends on the patient's age, comorbidities, and other factors 3.

Personalized Approach

• A patient-centric approach is key to HCM optimal management, and treatment should be personalized based on the patient's phenotype, risk stratification, preferences, needs, and beliefs 7.
• The evidence in support of the use of beta-blockers, non-dihydropyridine calcium channel blockers, disopyramide, and cardiac myosin inhibitors is discussed, and future perspectives in HCM management such as new drugs and gene therapies are explored 7.