For decreasing risk of sudden cardiac death in hypertrophic obstructive cardiomyopathy, which therapy is first-line?

• A. Beta blocker
• B. Calcium channel blocker
• C. Pacemaker
• D. AICD

Answer: (D)

In hypertrophic obstructive cardiomyopathy, the most effective way to prevent sudden cardiac death is an implantable cardioverter-defibrillator, because it directly detects and terminates malignant ventricular arrhythmias that cause SCD. While beta-blockers (and calcium channel blockers) help by reducing heart rate and LVOT obstruction to improve symptoms, they do not reliably prevent sudden death on their own.

AICD is used for high-risk patients even if they aren’t currently having arrhythmias, providing primary prevention against SCD. Pacemakers can help reduce obstruction in some cases, but they don’t address the dangerous arrhythmias that lead to SCD. Hence, the first-line therapy to decrease SCD risk in this condition is implantation of an AICD.