The prognostic value of reduced global longitudinal strain (GLS) on cardiac outcomes in patients on peritoneal dialysis: a prospective study

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction This study aims to evaluate the capacity of left ventricular global longitudinal strain (GLS) in end stage renal failure patients on peritoneal dialysis (PD) to predict cardiovascular mortality and major adverse cardiac events (MACE). GLS has been an established parameter in detecting subclinical left ventricular systolic dysfunction in the setting of preserved ejection fraction (EF > = 50%). We hypothesized that reductions of GLS (i.e. less negative value) are associated with adverse cardiovascular outcome. Methods We prospectively recruited a total of 60 PD patients from a single dialysis center in a tertiary hospital. GLS was determined by two-dimensional speckle-tracking echocardiography, under Philips QLab system. A less negative value reflects underlying subclinical LV dysfunction. The primary outcome was 4-point MACE, which was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and hospitalization for heart failure. Surrogate markers of inflammation (C-reactive protein [CRP], tumor necrosis factor [TNF]-alpha), nutrition (serum albumin), arterial stiffness (pulse wave velocity [PWV]), and serum N-terminal pro-brain natriuretic peptide (NT-proBNP) were also measured. Results 16 (26.7%) and 34 (56.7%) PD patients had reduced GLS (≥ -18.3%) and left ventricular hypertrophy (LVH) respectively. In 12-month follow up, 4-point MACE occurred in 13.6% and 59.8% of normal and compromised GLS patients respectively (log-rank, P = 0.004), as illustrated by Kaplan-Meier curves (Fig 1). Patients with reduced GLS had higher proportion of uncontrolled blood pressure and higher prevalence of coronary artery disease. Their EF were significantly lower (53.6 ± 7.4% vs. 61.3 ± 4.1%, P= 0.001) compared with patients with normal GLS. In addition, GLS correlated with EF (r = -0.57, P <0.0001) and PWV (r= 0.33, P = 0.01). There was a trend towards an association between GLS and ln(CRP) (r= 0.25, P = 0.057), and ln(NT-proBNP) (r = 0.22, P= 0.09), respectively. Conclusions Subclinical LV systolic dysfunction was present in one-fourth of peritoneal dialysis patients despite having preserved EF. Reduced GLS (less negative than 18.3%, illustrated in Fig 2) is a strong predictor of poor cardiovascular prognosis among PD population. Abstract Figure 1 Abstract Figure 2