CHRONIC FUROSEMIDE USE, RENAL FAILURE AND SURVIVAL IN PATIENS INDICATED TO CARDIAC RESYNCHRONIZATION THERAPY

Although loop diuretics are recommended in patiens with severe heart failure (HF) and clinical signs and symptom of congestion, renal failure and chronic diuretic use has been associated with an increase of mortality in HF.
Aim of the study: To assess the impact on survival of renal failure and chronic furosemid use in patiens with left ventricular (LV) dysfunction a ventricular dyssynchrony indicated for cardiac resynchronization therapy (CRT).
Methods: The study compromised 221 patients with chronic HF and LV ejection fraction (EF) < 0.30 who underwent CRT-D implantation (classe IA indication). Patiens were divided into quartiles of equivalent total daily furosemid dose: Group I: 0-12.5 mg, Group II: 12.6-25.0 mg, Group: III 26 – 62.5 mg and Group IV: > 62.5 mg. Mean follow-up was 42 m month.
Results:  Mean LV EF was 25.3 ± 8 %. Multivariate predictors of all cause mortality were renal failure (creatinin > 200 mmol/l)(hazard ratio (HR)1.57, p<0.002), NYHA class>3 (HR 1.89, p<0.001), furosemid daily dose > 62.5 mg (HR 1.96 , p<0.0001), age > 75 years ( HR 1.77, p < 0.0001), biventricular pacing< 80 % ( HR 1.84, p<0.001), left atrial size > 50 mm(HR 1.57, p < 0.001).
Survival was 86 % in group I, 81 % in group II, 70 % in group III and 51 % in group IV (long-rank statistics: 76.27, p < 0.0001).
Conclusion: Renal failure and furosemid daily dose > 25 mg as well as age > 75 years, dilatation of left atrium > 50 mm a low percentage of biventricular pacing were associated with a worsening in survival in patiens  with  implantable defibrillator and active biventricular pacing.