Effectiveness of cardiac resynchronization therapy by the frequency of revascularization procedures in ischemic cardiomyopathy patients.
BACKGROUND
It is not known whether the number of revascularizations modifies clinical outcomes in patients with ischemic cardiomyopathy (ICM) implanted with cardiac resynchronization therapy defibrillator (CRT-D) vs. an implantable cardioverter-defibrillator (ICD)-only.


METHODS
In Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT), we evaluated the effect of CRT-D vs. ICD-only on heart failure (HF) or death, on ventricular tachycardia (VT), ventricular fibrillation (VF) or death, and on reverse remodeling in 592 ICM patients with left bundle branch block, by the number of pre-enrollment revascularizations (0, 1 or ≥ 2 revascularizations).


RESULTS
There was a risk reduction of HF/death with CRT-D vs. ICD-only in all three sub-groups: ICM with no need for revascularization (HR 0.51 [0.26-1.02]; p = 0.055), ICM with 1 revascularization (HR 0.45 [0.30-0.70]; p < 0.001), and ICM with 2 or more revas-cularizations (HR 0.37 [0.20-0.66]; p < 0.001). Similarly, there was a risk reduction of VT/ /VF/death with CRT-D vs. ICD-only in patients with no need for revascularization (HR 0.55 [0.31-0.99]; p = 0.044); with 1 revascularization (HR 0.77 [0.51-1.18]; p = 0.23); or with ≥ 2 revascularizations (HR 0.63 [0.34-1.17]; p = 0.14). There was a similar degree of left ventricular reverse remodeling in all three subgroups (p > 0.05 for LVESV, LVEDV, and LAV percent change at 1-year follow-up).


CONCLUSIONS
In ICM patients, CRT-D is associated with a reduction in HF or death and VT/VF or death - irrespective of the frequency of pre-enrollment revascularization procedures - and is accompanied by a similar degree of beneficial left ventricular reverse remodeling.
Mustafa
M
Husaini
Yitschak
Y
Biton
Brad
B
Stair
Arthur J
AJ
Moss
Tor
T
Biering-Sørensen
Scott
S
Solomon
Scott
S
McNitt
Bronislava
B
Polonsky
Wojciech
W
Zareba
Alon
A
Barsheshet
Heart Research Follow-up at the University of Rochester Medical Center. Valentina.Kutyifa@heart.rochester.edu.
Valentina
V
Kutyifa
D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D009202:Cardiomyopathies / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D017202:Myocardial Ischemia / Q000150:complications* / Q000503:physiopathology / Q000601:surgery; D009204:Myocardial Revascularization / Q000379:methods*; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome
cardiac resynchronization therapy; heart failure; implantable cardioverter- -defibrillator; ventricular tachyarrhythmias