From the Guidelines
The primary management approach for asymmetric septal hypertrophy (ASH) and hypertrophic cardiomyopathy (HCM) involves a comprehensive strategy that includes medical therapy, invasive options, and lifestyle modifications, with the goal of reducing symptoms, preventing sudden cardiac death, and improving quality of life, as outlined in the most recent guidelines 1. The management of ASH and HCM typically begins with beta-blockers, such as metoprolol (25-100 mg twice daily), or non-dihydropyridine calcium channel blockers, like verapamil (120-480 mg daily in divided doses), to reduce heart rate, improve diastolic filling, and decrease outflow tract obstruction.
- Key considerations in the management of ASH and HCM include:
- Risk stratification for sudden cardiac death, with implantable cardioverter-defibrillator placement recommended for high-risk individuals 1.
- Lifestyle modifications, such as avoiding dehydration, excessive alcohol, and strenuous exercise, to reduce the risk of complications.
- Genetic counseling, as HCM is often hereditary (autosomal dominant) 1.
- The use of cardiac myosin inhibitors, such as mavacamten, for patients with symptomatic obstructive HCM who do not derive adequate symptomatic relief from first-line drug therapy 1.
- Invasive septal reduction therapies, including surgical septal myectomy and alcohol septal ablation, for patients with drug-refractory or severe outflow tract obstruction, which can provide safe and effective symptomatic relief when performed by experienced HCM teams at dedicated centers 1. The most recent guidelines emphasize the importance of shared decision-making, careful risk stratification, and individualized treatment planning to optimize outcomes for patients with ASH and HCM 1.
From the Research
Asymmetric Septal Hypertrophy versus Hypertrophic Cardiomyopathy
The primary management approach for asymmetric septal hypertrophy versus hypertrophic cardiomyopathy involves several key considerations:
- Pharmacologic therapy: Beta-adrenergic blocking drugs and calcium channel blockers are the principal treatment strategies in symptomatic patients with left ventricular outflow obstruction, as noted in 2.
- Septal reduction strategies: When symptoms prove refractory to medical therapy, septal reduction strategies such as surgical myectomy and alcohol septal ablation are effective, with the choice of strategy depending on various factors, including the medical system providing treatment and patient characteristics, as discussed in 2 and 3.
- Patient selection: Proper patient selection is crucial for achieving similar low mortality rates between ventricular septal myectomy and alcohol septal ablation, and this selection should be performed in high-volume clinical environments, as emphasized in 3.
- Symptomatic management: Patients with hypertrophic cardiomyopathy should be prohibited from participating in competitive sports or performing strenuous activities, and should be placed on high-dose beta-blockers and followed closely, with monitoring for arrhythmias and other complications, as recommended in 4.
Key Differences and Considerations
Some key differences and considerations between asymmetric septal hypertrophy and hypertrophic cardiomyopathy include:
- Definition and terminology: Hypertrophic cardiomyopathy is a more accurate term for the condition also known as idiopathic hypertrophic subaortic stenosis, asymmetric septal hypertrophy, or hypertrophic obstructive cardiomyopathy, as noted in 4.
- Pathophysiology: The principal abnormality in systole is the obstruction to left ventricular outflow caused by upper septal hypertrophy, which can lead to mitral regurgitation and other complications, as described in 5.
- Treatment outcomes: Contemporary myectomy may have superior outcomes compared to alcohol septal ablation in some cases, but the choice of treatment depends on various factors, including patient characteristics and the medical system providing treatment, as discussed in 3.