Predictors of a positive response to biventricular pacing in patients with severe heart failure and ventricular conduction delay.
BACKGROUND
Cardiac resynchronization therapy (CRT) is recommended in patients with ejection fraction <35%, QRS width> 120 ms, and New York Heart Association (NYHA) functional class III or IV despite optimal medical therapy. We aimed to define demographic, clinical, and electrocardiographic predictors of positive clinical response to CRT.


RESULTS
Hundred consecutive patients fulfilling the recommended criteria were implanted with a CRT device. Demographic, clinical, two-dimensional echocardiographic and electrographic parameters were measured at baseline and after 6 months of simultaneous biventricular pacing. A positive response to CRT included an improvement of at least one NYHA functional class associated with an absence of hospitalization for worsening heart failure. At the end of follow-up, 12 patients were dead and 71% of the patients were classified as responders. After 6 months of CRT, the ejection fraction was significantly higher (P = 0.035) in responders versus nonresponders. Multivariate analysis identified three independent predictors of positive response to CRT: an idiopathic origin of the cardiomyopathy (P = 0.043), a wider QRS before implantation (P = 0.017), and a narrowing of the QRS after implantation (P = 0.037).


CONCLUSIONS
An idiopathic origin of the cardiomyopathy, a wider QRS before implantation, and a narrowing of the QRS width after implantation were identified as independent predictors of clinical positive response to CRT.
Hospital Haut Leveque, Service Pr Clementy, Pessac, France.
Sunthareth
S
Yeim
Pierre
P
Bordachar
Sylvain
S
Reuter
Julien
J
Laborderie
Mark D
MD
O'Neill
Stephane
S
Lafitte
Antoine
A
Deplagne
Stephane
S
Garrigue
Raymond
R
Roudaut
Pierre
P
Jais
Michel
M
Haissaguerre
Pierre
P
Dossantos
Jacques
J
Clementy
D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006333:Heart Failure / Q000150:complications / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D016015:Logistic Models; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016896:Treatment Outcome; D018754:Ventricular Dysfunction / Q000150:complications / Q000503:physiopathology* / Q000628:therapy*