Prognosis in hypertrophic cardiomyopathy.

Area of Science:

• Cardiology
• Clinical Medicine
• Genetics

Background:

• Hypertrophic cardiomyopathy (HCM) is a significant cause of sudden cardiac death.
• Long-term prognostic factors in HCM require further elucidation, particularly in diverse ethnic populations.

Purpose of the Study:

• To investigate the long-term prognosis and identify risk factors for adverse outcomes in Japanese patients with hypertrophic cardiomyopathy.
• To compare the prognostic profile of Japanese HCM patients with that of Western cohorts.

Main Methods:

• A retrospective longitudinal study of 136 patients diagnosed with hypertrophic cardiomyopathy.
• Life table analysis was employed to assess survival rates and identify predictors of sudden death and heart failure.
• Clinical data, including age, electrocardiographic findings (Master's single two-step test), and hemodynamic measurements (left ventricular end-diastolic pressure), were analyzed.

Main Results:

• During a 1-17 year follow-up, 21 deaths occurred, with 14 attributed to sudden cardiac death.
• Sudden death was significantly associated with age under 20 years (relative risk [RR] = 8.63) and a positive Master's single two-step test (RR = 3.55).
• Heart failure was more common in patients with a positive Master's test (RR = 4.27) and elevated left ventricular end-diastolic pressure (>20 mm Hg, RR = 2.58). Atrial fibrillation emerged as a poor prognostic indicator.
• Patients with apical hypertrophy and giant negative T waves demonstrated a favorable outcome.

Conclusions:

• Prognosis in Japanese patients with hypertrophic cardiomyopathy aligns with Western populations, with identifiable risk factors for sudden death and heart failure.
• Younger age, abnormal exercise test results, and atrial fibrillation are associated with poorer outcomes.
• Apical hypertrophy with specific electrocardiographic features represents a favorable prognostic subtype.