Résumé
Diastolic Asynchrony Is More Frequent Than Systolic Asynchrony in Dilated Cardiomyopathy and Is Less Improved by Cardiac Resynchronization Therapy
Iris Schuster, Gilbert Habib, Christophe Jego, Franck Thuny, Jean-François Avierinos, Geneviéve Derumeaux, Lionel Beck, Christine Medail, Frederic Franceschi, Sebastien Renard, Ange Ferracci, Jean Lefevre, Roger Luccioni, Jean-Claude Deharo, Pierre Djiane
To assess the role of diastolic asynchrony in patients with congestive heart failure (CHF), tissue Doppler imaging (TDI) was performed in 116 CHF patients. Among them, 42 underwent TDI studies before and after CRT. Diastolic asynchrony was more frequent than systolic (58% vs. 47%; p = 0.0004; for intraventricular; and 72% vs. 45%; p < 0.0001; for interventricular asynchrony). It was isolated in one-third of CHF patients and was weakly correlated with QRS duration. Diastolic intraventricular asynchrony decreased from 81% to 55% (p < 0.0002) after CRT, but was less improved than systolic asynchrony.
To compare the incidence of diastolic and systolic asynchrony, assessed by tissue Doppler imaging (TDI), in patients with congestive heart failure (CHF) and severe left ventricular (LV) dysfunction, and to assess TDI changes induced by cardiac resynchronization therapy (CRT).
Thirty percent of CRT candidates are nonresponders. Besides QRS width, the presence of echographic systolic asynchrony has been used to identify future responders. Little is known about diastolic asynchrony and its change after CRT.
Tissue Doppler imaging was performed in 116 CHF patients (LV ejection fraction 26 ± 8%). Systolic and diastolic asynchrony was calculated using TDI recordings of right ventricular and LV walls.
The CHF group consisted of 116 patients. Diastolic asynchrony was more frequent than systolic, concerning both intraventricular (58% vs. 47%; p = 0.0004) and interventricular (72 vs. 45%; p < 0.0001) asynchrony. Systolic and diastolic asynchrony were both present in 41% patients, but one-third had isolated diastolic asynchrony. Although diastolic delays increased with QRS duration, 42% patients with narrow QRS presented with diastolic asynchrony. Conversely, 27% patients with large QRS had no diastolic asynchrony. Forty-two patients underwent CRT. Incidence of systolic intraventricular asynchrony decreased from 71% to 33% after CRT (p < 0.0001), but diastolic asynchrony decreased only from 81% to 55% (p < 0.0002). Cardiac resynchronization therapy induced new diastolic asynchrony in eight patients.
Diastolic asynchrony is weakly correlated with QRS duration, is more frequent than systolic asynchrony, and may be observed alone. Diastolic asynchrony is less improved by CRT than systolic. Persistent diastolic asynchrony may explain some cases of lack of improvement after CRT despite good systolic resynchronization.