Mechanical Dyssynchrony by Tissue Doppler Cross-Correlation is Associated with Risk for Complex Ventricular Arrhythmias after Cardiac Resynchronization Therapy.
BACKGROUND
Tissue Doppler cross-correlation analysis has been shown to be associated with long-term survival after cardiac resynchronization defibrillator therapy (CRT-D). Its association with ventricular arrhythmia (VA) is unknown.


METHODS
From two centers 151 CRT-D patients (New York Heart Association functional classes II-IV, ejection fraction ≤ 35%, and QRS duration ≥ 120 msec) were prospectively included. Tissue Doppler cross-correlation analysis of myocardial acceleration curves from the basal segments in the apical views both at baseline and 6 months after CRT-D implantation was performed. Patients were divided into four subgroups on the basis of dyssynchrony at baseline and follow-up after CRT-D. Outcome events were predefined as appropriate antitachycardia pacing, shock, or death over 2 years.


RESULTS
Mechanical dyssynchrony was present in 97 patients (64%) at baseline. At follow-up, 42 of these 97 patients (43%) had persistent dyssynchrony. Furthermore, among 54 patients with no dyssynchrony at baseline, 15 (28%) had onset of new dyssynchrony after CRT-D. In comparison with the group with reduced dyssynchrony, patients with persistent dyssynchrony after CRT-D were associated with a substantially increased risk for VA (hazard ratio [HR], 4.4; 95% CI, 1.2-16.3; P = .03) and VA or death (HR, 4.0; 95% CI, 1.7-9.6; P = .002) after adjusting for other covariates. Similarly, patients with new dyssynchrony had increased risk for VA (HR, 10.6; 95% CI, 2.8-40.4; P = .001) and VA or death (HR, 5.0; 95% CI, 1.8-13.5; P = .002).


CONCLUSIONS
Persistent and new mechanical dyssynchrony after CRT-D was associated with subsequent complex VA. Dyssynchrony after CRT-D is a marker of poor prognosis.
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark. Electronic address: bhupendar.tayal@gmail.com.
Bhupendar
B
Tayal
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
John
J
Gorcsan
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Antonia
A
Delgado-Montero
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Josef J
JJ
Marek
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Kristina H
KH
Haugaa
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Keiko
K
Ryo
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Akiko
A
Goda
Department of Cardiology, Rigshospitalet, Copenhagen, Denmark.
Niels Thue
NT
Olsen
Division of Cardiology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Samir
S
Saba
Department of Cardiology, Hvidovre University Hospital, Copenhagen, Denmark.
Niels
N
Risum
Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark.
Peter
P
Sogaard
D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods* / Q000401:mortality; D003718:Denmark / Q000453:epidemiology; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010414:Pennsylvania / Q000453:epidemiology; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology*; D015996:Survival Rate / Q000639:trends; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000628:therapy; D013997:Time Factors; D016896:Treatment Outcome
Cardiac resynchronization defibrillator therapy; Dyssynchrony; Echocardiography; Heart failure; Ventricular arrhythmia