[Prevalence of pulmonary hypertension in patients with hypertrophic obstructive cardiomyopathy: a case-control study]

Objective: To explore the clinical characteristics and risk factors of pulmonary hypertension (PH) in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods: A total of 301 patients admitted in Fuwai Hospital and diagnosed with HOCM were included in our study. Incidence rate and severity of PH were depicted. The study population was divided into two groups (PH group and control group), and the differences in clinical profile were elucidated. Risk factors of PH in patients with HOCM were assessed by multivariate logistic regression analysis. Results: The incidence of PH was 12.3% (37 cases), in which 48.6% patients (18 cases) were mild PH, 40.5% patients (15 cases) were moderate PH, and patients with severe PH accounts for 10.8% (4 cases). Multivariate logistic regression analysis indicated that female(OR=3.95, 95%CI 1.74-8.98, P=0.001), age ≥65 years(OR=3.87, 95%CI 1.16-12.97, P=0.030), history of atrial fibrillation(OR=2.76, 95%CI 1.01-7.57, P=0.049)and moderate or severe mitral regurgitation(OR=6.63, 95%CI 3.02-14.57, P=0.000)were independent risk factors of PH. Stratification according to sex showed that age ≥65 years(OR=7.79, 95%CI 1.35-47.26, P<0.05)and moderate or severe mitral regurgitation(OR=9.83, 95%CI 2.26-42.67, P<0.01)were independent risk factors of PH for male patients; while history of atrial fibrillation(OR=6.32, 95%CI 1.57-25.40, P=0.01)and moderate or severe mitral regurgitation(OR=5.23, 95%CI 1.92-14.26, P<0.01)were independent risk factors of PH for female patients. Risk factors were similar between the mild PH group and moderate to severe PH groups. Conclusion: Compared with patients without PH, HOCM patients complicated with PH were older and with higher percentage of female, and resting obstruction, history of atrial fibrillation and moderate or severe mitral regurgitation. Independent risk factors for PH in obstructive hypertrophic cardiomyopathy patients are female, advanced age, history of atrial fibrillation and moderate or severe mitral regurgitation.