Association of cardiac resynchronization therapy with the incidence of appropriate implantable cardiac defibrillator therapies in ischaemic and non-ischaemic cardiomyopathy.
OBJECTIVE
Cardiac resynchronization therapy (CRT) reduces the incidence of sudden cardiac death and the use of appropriate implantable cardioverter-defibrillator (ICD) therapies (AICDTs); however, this antiarrhythmic effect is only observed in certain groups of patients. To gain insight into the effects of CRT on ventricular arrhythmia (VA) burden, we compared the incidence of AICDT use in four groups of patients: patients with ischaemic cardiomyopathy vs. non-ischaemic dilated cardiomyopathy (NIDC) and patients implanted with an ICD vs. CRT-ICD.


RESULTS
We analysed 689 consecutive patients (mean follow-up 37 ± 16 months) included in the Umbrella registry, a multicentre prospective registry including patients implanted with ICD or CRT-ICD devices with remote monitoring capabilities in 48 Spanish Hospitals. The primary outcome was the time to first AICDT. Despite a worse clinical risk profile, NIDC patients receiving a CRT-ICD had a lower cumulative probability of first AICDT use at 2 years compared with patients implanted with an ICD [24.7 vs. 41.6%, hazard ratio (HR): 0.49, P = 0.003]; on the other hand, there were no significant differences in the incidence of first AICDT use at 2 years in ischaemic patients (22.6 vs. 21.9%, P = NS). Multivariate analysis confirmed the association of CRT with lower AICDT rates amongst NIDC patients (Adjusted HR: 0.55, CI 95% 0.35-0.87).


CONCLUSIONS
These data suggest that CRT is associated with significantly lower rates of first AICDT use in NIDC patients, but not in ischaemic patients. This study suggests that ICD patients with NIDC and left bundle branch block experiencing VAs may benefit from an upgrade to CRT-ICD despite being in a good functional class.
Hospital General Universitario Gregorio Marañon, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Calle Dr. Esquerdo 46, 28007 Madrid, Spain.
Gerard
G
Loughlin
Hospital General Universitario Gregorio Marañon, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Calle Dr. Esquerdo 46, 28007 Madrid, Spain.
Pablo
P
Avila
Hospital Universitario de Araba, Vitoria, Spain.
Jose B
JB
Martinez-Ferrer
Hospital Virgen de la Victoria, Malaga, Spain.
Javier
J
Alzueta
Hospital Santa Creu i Sant Pau, Barcelona, Spain.
Xavier
X
Vinolas
Hospital Clinic, Barcelona, Spain.
Josep
J
Brugada
Hospital Reina Sofia, Cordoba, Spain.
Jose M
JM
Arizon
Hospital Universitario Puerta de Hierro, Majadahonda, Spain.
Ignacio
I
Fernandez-Lozano
Complejo Hospitalario de Vigo, Vigo, Spain.
Enrique
E
García-Campo
Hospital de Navarra, Pamplona, Spain.
Nuria
N
Basterra
Hospital Infanta Cristina, Badajoz, Spain.
Joaquin
J
Fernandez De La Concha
Hospital General Universitario Gregorio Marañon, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Calle Dr. Esquerdo 46, 28007 Madrid, Spain.
Angel
A
Arenal
D000328:Adult; D000368:Aged; D002037:Bundle-Branch Block / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D058406:Cardiac Resynchronization Therapy; D058409:Cardiac Resynchronization Therapy Devices; D009202:Cardiomyopathies / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D018572:Disease-Free Survival; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012042:Registries; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D013997:Time Factors; D016896:Treatment Outcome
Cardiac resynchronization therapy; Implantable cardioverter-defibrillator; Remodelling; Ventricular arrhythmia