What is the recommended management for hypertrophic cardiomyopathy?

Management of Hypertrophic Cardiomyopathy

The management of hypertrophic cardiomyopathy requires a comprehensive approach centered on sudden cardiac death risk stratification, treatment of left ventricular outflow tract obstruction when present, and genetic counseling with family screening. 1

Initial Assessment and Risk Stratification

Sudden Cardiac Death Risk Assessment

• Integrate established risk markers with validated risk estimation tools to determine implantable cardioverter-defibrillator (ICD) candidacy. 1
• Risk factors carry different weights in children versus adults—pediatric stratification must account for age and body size. 1
• The European and American guidelines diverge here: European guidelines advocate for a validated Risk-SCD calculator, while American guidelines rely on specific individual risk markers for personalized evaluation. 2
• ICD decisions should incorporate the patient's personal risk tolerance and treatment goals through shared decision-making. 1

Genetic Testing and Family Screening

• Obtain detailed family history and counsel patients about genetic transmission patterns. 1
• Screen first-degree family members using genetic testing, serial imaging, or electrocardiographic surveillance beginning at any age. 1
• Reconfirm reported pathogenicity of detected variants every 2-3 years, as screening recommendations for family members depend on variant pathogenicity. 1
• Referral to specialized HCM centers with genetics expertise is valuable for interpreting genetic testing results. 1

Management of Obstructive HCM

First-Line Medical Therapy

• Initiate beta-blockers or calcium channel blockers (verapamil/diltiazem) as first-line therapy for patients with resting or provocable left ventricular outflow tract (LVOT) obstruction. 2

Second-Line Medical Therapy

• If beta-blockers or calcium channel blockers provide inadequate symptomatic relief, add either disopyramide or the cardiac myosin inhibitor mavacamten. 1, 2
• Mavacamten is the only FDA-approved cardiac myosin inhibitor that decreases cardiac contractility by inhibiting actin-myosin interaction, thereby reducing LVOT obstruction. 1
• This new drug class represents an evidence-based alternative to septal reduction therapies for symptomatic obstructive HCM. 3

Invasive Septal Reduction Therapy

• Refer patients with drug-refractory or severe outflow tract obstruction to experienced HCM centers for surgical septal myectomy or alcohol septal ablation. 1
• These procedures provide safe and effective symptomatic relief when performed by experienced teams at dedicated centers with significantly improved outcomes. 1
• American guidelines suggest earlier myectomy for certain clinical factors, while European guidelines recommend septal reduction for symptomatic patients with significant LVOT gradients. 2
• Sequential atrioventricular pacing and dual-chamber defibrillators may reduce LVOT gradients per European guidelines. 2

Management of Non-Obstructive HCM

• Effective treatments for non-obstructive HCM remain limited, with several clinical trials ongoing. 3
• Focus on symptom management with standard heart failure therapies, though evidence is less robust than for obstructive disease. 3

Atrial Fibrillation Management

• Anticoagulate all patients with HCM and persistent or paroxysmal atrial fibrillation using direct-acting oral anticoagulants (or warfarin) due to sufficiently increased stroke risk. 1
• Rhythm control is essential for patients with symptomatic atrial fibrillation. 3

Advanced Heart Failure

• Early identification of advanced heart failure is critical for improving outcomes with cardiac transplantation and other advanced therapies. 3
• Though uncommon, advanced heart failure represents an important cause of morbidity and mortality in HCM. 3

Exercise Recommendations

• Adopt an individualized approach to exercise restrictions rather than blanket prohibitions on vigorous activity. 3
• Newer data suggest arrhythmic risk with exercise is lower than historically believed. 3
• Supervised, individualized exercise training through hybrid cardiac telerehabilitation improves functional capacity (peak VO₂) and 6-minute walk distance in carefully selected patients with non-obstructive HCM and preserved ejection fraction without serious adverse events. 4

Referral to Specialized Centers

Refer to multidisciplinary HCM centers for: 1

• Challenging treatment decisions where reasonable alternatives exist
• Any decision with weak strength of recommendation (Class 2b)
• Interpretation of genetic testing results
• Primary prevention ICD decision-making
• HCM-specific invasive procedures (septal reduction therapies)

Imaging Surveillance

• Echocardiography forms the cornerstone of diagnostic assessment with broad consensus across guidelines. 5
• American guidelines emphasize periodic cardiac magnetic resonance imaging for ongoing assessment. 2
• Variability exists between guidelines regarding the utility of late gadolinium enhancement for risk stratification. 5