維持透析患者の心機能に関する研究 ： 左室拡張期特性とその規定因子

Abstract

To investigate the left ventricular diastolic property and its determinants in patients on maintenance hemodialysis, 35 patients undergoing stable hemodialysis were examined noninvasively using echocardiography and mechanocardiography before and after a single hemodialysis. Subjects were classified on the basis of their total left ventricular wall thickness (TLVT) into 2 groups : Group T1, 16 patients with TLVT less than 2.4 cm, and Group T2, 19 patients with TLVT 2.4 cm or more. As a control 10 healthy men (Group C) were also examined. Early diastolic time intervals were measured as follows : IRT, MVo-O and Ⅱᴀ-O. M-mode echocardiogram was digitized and continuous plots made from left ventricular dimension and its change in dimension were obtained. Diastolic phase was divided into three periods : rapid filling (rf), slow filling (sf) and atrial contraction (ac). Then diastolic time intervals (Prf, Psf, Pac), changes of left ventricular dimension (Drf, Dsf, Dac) and peak rates of increase of left ventricular dimension (max dDrf/dt, max dDac/dt) were measured. The results were as follows : (1) In Group T2, MBP was higher, HR was more increased, LVDd was larger, IRT, Ⅱᴀ-O and Prf were more prolonged, max Drf/dt and Drf were more decreased, max dDac/dt and Dac were more increased as compared with Group C and Group T1. (2) All indices of the left ventricular diastolic property were unchanged before and after a single hemodialysis. (3) Multiple regression analysis for indicies of left ventricular diastolic property and various clinical parameters in patients on maintenance hemodialysis showed that high MBP and increased TLVT contributed to the prolongation of IRT, Ⅱᴀ-O and Prf, and the decrease of max dDrf/dt. These findings suggest that maintenance hemodialysis patients with left ventricular hypertrophy have deterioration of left ventricular diastolic property, and its deterioration mainly depends on TLVT and blood pressure, but the reduction of volume-overload by a single hemodialysis makes no improvement in left ventricular diastolic dysfunction.