Abstract 12527: Baseline Mechanical Dyssynchrony is Predictive of Improvement in Renal Insufficiency and Response Rate Following Cardiac Resynchronization Therapy
Background: Renal insufficiency and heart failure (HF) often coexist and indicate poor prognosis. Although cardiac resynchronization therapy (CRT) benefits many HF patients (pts) with wide QRS and low ejection fraction (EF), factors which impact improvement in renal function following CRT are unclear.
Objective: To test the hypothesis that the presence of baseline mechanical dyssynchrony in pts with renal insufficiency is predictive of improvement in renal function following CRT.
Methods: We studied 78 CRT pts with renal insufficiency defined as glomerular filtration rate (GFR) <60 ml/min/1.73 m2. All had NYHA III-IV, EF ≤35% and QRS≥120ms. Baseline dyssynchrony was assessed by mid-ventricular speckle tracking radial strain. Dyssynchrony was defined as the anteroseptum to posterior wall delay ≥ 130ms. GFR was determined at baseline and 3 month after CRT. Left ventricular reverse remodeling was defined as ≥10% relative decrease in end systolic volume. EF response was defined as ≥ 5% absolute increase.
Results: Dyssynchrony determination was feasible in 72 pts (94%). 14 pts were excluded (8 with events before 3 month follow up and 6 on hemodialysis). The study group included 59 renal insufficiency pts (30 with dyssynchrony and 29 without dyssynchrony). Pts with and without dyssynchrony had similar baseline characteristics, except male gender was more common in non-dyssynchrony group (60% vs. 89%, p value= 0.02). Baseline GFR was similar between the 2 groups (46±10 vs.40±10, p=ns). Renal insufficiency pts with baseline dyssynchrony had a significant GFR improvement (5.68±8 vs. 0.4±10, p=0.02), more reverse remodeling (75% vs.24%, p=0.001) and higher EF response (63% vs.29%, p=0.04).
Conclusion: In HF patients with renal insufficiency, mechanical dyssynchrony before CRT was associated with a greater improvement in GFR, reverse remodeling and EF response, than those who lacked dyssynchrony, and is of clinical prognostic value.
- © 2012 by American Heart Association, Inc.