The incremental effect of obstructive sleep apnea syndrome on right and left ventricular myocardial performance in newly diagnosed essential hypertensive subjects

Abstract

Obstructive sleep apnea syndrome (OSAS) may predispose patients to congestive heart failure, suggesting a deleterious effect of OSAS on myocardial contractility. We investigated whether essential hypertensive individuals with OSAS are characterized by decreased right and left ventricular myocardial performance. Our study population consisted of 45 consecutive patients with newly diagnosed untreated stage I-II essential hypertension suffering from OSAS (35 men, aged 49 ± 8 years) and 48 hypertensives without OSAS, matched for age, sex, level of blood pressure, heart rate, body mass index and smoking status. All subjects underwent polysomnography and echocardiography. Right and left ventricular functions were evaluated using the myocardial performance index (MPI). Right and left ventricular functions were altered in hypertensives with OSAS. The mean right MPI was 0.26 ± 0.11 in hypertensives without OSAS and 0.51 ± 0.16 in hypertensives with OSAS (P<0.01). The mean left MPI values were 0.29 ± 0.07 and 0.44 ± 0.13, respectively (P<0.01). Right and left MPI correlated positively and significantly with apnea-hypopnea index (ρ=0.40, P=0.002).OSAS is associated with impaired right and left ventricular function. These phenomena were independent of hypertension.