Regression of left ventricular mass following conversion from conventional hemodialysis to thrice weekly in-centre nocturnal hemodialysis

Abstract

ABSTRACT: BACKGROUND: Increased left ventricular mass (LVM) is associated with adverse outcomes in patients receiving chronic hemodialysis. Among patients receiving conventional hemodialysis (CHD, 3x/week, 4 hrs/session), we evaluated whether dialysis intensification with in-centre nocturnal hemodialysis (INHD, 3x /week, 7-8 hrs/session in the dialysis unit) was associated with regression of LVM. METHODS: We conducted a retrospective cohort study of CHD recipients who converted to INHD and received INHD for at least 6 months. LVM on the first echocardiogram performed at least 6 months post-conversion was compared to LVM pre-conversion. In a secondary analysis, we examined echocardiograms performed at least 12 months after starting INHD. The effect of conversion to INHD on LVM over time was also evaluated using a longitudinal analysis that incorporated all LVM data on patients with 2 or more echocardiograms. RESULTS: Thirty-seven patients were eligible for the primary analysis. Mean age at conversion was 49 +/-12 yrs and 30% were women. Mean pre-conversion LVM was 219 +/- 66 g and following conversion, LVM declined by 32 +/- 58 g (p=0.002). Among patients whose follow-up echocardiogram occurred at least 12 months following conversion, LVM declined by 40 +/- 56 g (p=0.0004). The rate of change of LVM decreased significantly from 0.4 g/yr before conversion, to -11.7 g/yr following conversion to INHD (p<0.0001). CONCLUSION: Conversion to INHD is associated with a significant regression in LVM, which may portend a more favourable cardiovascular outcome. Our preliminary findings support the need for randomized controlled trials to definitively evaluate the cardiovascular effects of INHD.