Comparison of prevalence, clinical course, and pathological findings of left ventricular systolic impairment versus normal systolic function in patients with hypertrophic cardiomyopathy.

FERNANDEZ A; VIGLIANO CA; CASABE JH; DIEZ M; FAVALORO LE; GUEVARA E; FAVALORO RR; LAGUENS RP

AMERICAN JOURNAL OF CARDIOLOGY

EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC

Año: 2011 vol. 108 p. 548 - 555

0002-9149

Impaired left ventricular systolic function (ILVSF) in hypertrophic cardiomyopathy (HC) is a risk factor for sudden death and a determinant of high mortality. We determined its prevalence, clinical parameters, long-term outcome, and pathologic findings of explanted hearts. We retrospectively analyzed 382 patients with HC; ILVSF was characterized by LV ejection fraction <50% at rest and was identified in 24 patients (6.3%). Patients with ILVSF were younger than patients with normal SF (43.5 ± 14.1 vs 55.3 ± 20.4 years, p = 0.001) and had larger LV end-diastolic cavity diameter (53.2 ± 12.2 vs 43.8 ± 6.2 mm, p = 0.001), larger left atrium (51.2 ± 6.5 vs 44.3 ± 8 mm, p <0.001), and lower fractional shortening (30.7 ± 11.1% vs 45.5% ± 10.3%, p <0.001). A combined end point (heart failure death or heart transplantation) was considered. Median follow-up was 3 years (1.2 to 6.3). Fourteen patients with ILVSF (58.3%) had the end point compared to 3 (0.8%) with normal SF (p <0.001). In explanted hearts, fibrosis represented 30.5 ± 12.5% of the left ventricle; we observed a direct correlation between fibrosis and ventricular dilation (r = 0.794, p = 0.001) and an inverse correlation between fibrosis and ejection fraction (r = -0.623, p = 0.023). Number and length density of small arterioles (<50 microns in diameter) were significantly decreased. In conclusion, ILVSF in HC has a poor prognosis and is associated with fibrosis and selective decreased development of small arterioles.