Kidney dysfunction and deterioration of ejection fraction pose independent risk factors for mortality in implantable cardioverter-defibrillator recipients for primary prevention.
BACKGROUND
A growing number of patients with advanced heart failure fulfill a primary-prevention indication for an implantable cardioverter-defibrillator (ICD). This study seeks to identify new predictors of overall mortality in a Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT)-like collective to enhance risk stratification.


OBJECTIVE
An impaired renal function and severely depressed left ventricular ejection fraction pose relevant risk factors for mortality in primary prevention ICD recipients.


METHODS
Ninety-four consecutive ICD patients with New York Heart Association class II-III heart failure and depressed left ventricular function (left ventricular ejection fraction [LVEF] ≤ 35%) with no history of malignant ventricular arrhythmias were followed for 34 ± 20 months.


RESULTS
During this period, 30 patients died (32%). Deceased patients revealed a significantly worse renal function before ICD implantation (1.55 ± 0.7 mg/dL vs 1.1 ± 0.4 mg/dL; P = 0.007), suffered more often from coronary artery disease (53 vs 29; P = 0.006), and were older (69.5 ± 8 y vs 67 ± 12 y; P = 0.0002) than surviving patients. Furthermore, increased serum creatinine at baseline (2 mg/dL vs 1 mg/dL; odds ratio [OR]: 3.96, 95% confidence interval [CI]: 1.2-13.04, P = 0.02), presence of coronary artery disease (OR: 8.6, 95% CI: 1.1-65, P = 0.036), and low LVEF (OR per 5% baseline LVEF deterioration: 1.4, 95% CI: 1-1.8, P = 0.034) represented strong and independent predictors for overall mortality.


CONCLUSIONS
Impaired renal function, the presence of coronary artery disease, and reduced LVEF before implantation represent independent predictors for mortality in a cohort of patients with advanced systolic heart failure. These conditions still bear a high mortality risk, even if ICD implantation effectively prevents sudden arrhythmic death. Indeed, in patients suffering from several of the identified "high-risk" comorbidities, primary-prevention ICD implantation might have a limited survival benefit. The possible adverse effects of these comorbidities should be openly discussed with the potential ICD recipient and his or her close relatives.
Department of Medicine-Cardiology, University Hospital Bonn, Bonn, Germany.
Jens
J
Kreuz
Fritz
F
Horlbeck
Jan
J
Schrickel
Markus
M
Linhart
Rolf
R
Fimmers
Fritz
F
Mellert
Georg
G
Nickenig
Jörg Otto
JO
Schwab
D000368:Aged; D001145:Arrhythmias, Cardiac; D016757:Death, Sudden, Cardiac / Q000209:etiology* / Q000517:prevention & control; D017147:Defibrillators, Implantable; D005500:Follow-Up Studies; D006333:Heart Failure / Q000150:complications* / Q000401:mortality / Q000628:therapy; D006801:Humans; D007674:Kidney Diseases / Q000150:complications* / Q000401:mortality; D011322:Primary Prevention; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D016019:Survival Analysis; D018487:Ventricular Dysfunction, Left / Q000150:complications* / Q000401:mortality