Hypertrophic cardiomyopathy in the elderly: significance of atrial fibrillation.

BACKGROUND AND

OBJECTIVES

Atrial fibrillation (Af) is an important prognostic indicator for clinical deterioration in patients with hypertrophic cardiomyopathy (HCM), particularly in elderly patients, but its significance may vary from unselected to selected populations. This study investigated the risk of Af as a prognostic factor in long-term mortality and morbidity in Japanese patients with HCM at our institution.

METHODS

All fatal and non-fatal cardiovascular events were estimated in 91 patients with HCM (mean age 51 +/- 14 years, 62 men) and follow up continued for 6.7 +/- 4.8 years.

RESULTS

Either chronic or paroxysmal Af documented by standard electrocardiography (ECG) or ambulatory ECG monitoring at diagnosis and during follow-up were included with other clinical features in the survival analysis. Af was documented in 22 patients (24%). They were older than those without Af (57 +/- 10 vs 48 +/- 14 years, p < 0.005) and had larger left atrial dimensions (43 +/- 6 vs 36 +/- 5 mm, p < 0.01). Cardiovascular events occurred in 12 patients with Af (embolic events in five, heart failure in four, and sudden death in three), and in four patients without Af (embolic event in one, and sudden death in three). Death occurred in 10 patients (seven with Af and three without Af); sudden death in six patients (three with Af and three without Af) and four patients died of cerebrovascular embolism (four with Af and none without Af). Cox's regression analysis showed the occurrence of Af was the most useful predictor of cardiovascular death in patients with HCM. The event-free rate was significantly worse in patients with Af than in those without Af (p < 0.0001).

CONCLUSIONS

Af is an important prognostic feature in patients with HCM, which occurs in older patients and in those with left atrial dilation.