Absence of additional improvement in outcome of patients receiving cardiac resynchronization therapy paced at the most delayed left ventricular region.
BACKGROUND
The choice of the optimal left ventricular (LV) pacing site remains an issue in patients requiring cardiac resynchronization therapy (CRT).


OBJECTIVE
This prospective study compared the outcome of patients paced at the most delayed LV region with that of patients paced at any other LV site.


METHODS
Forty-four patients with severe heart failure underwent three-dimensional (3D) echocardiography before implantation and 3 days after implantation of a CRT device, to determine the most delayed LV region during spontaneous rhythm and during right ventricular pacing. The patients were divided subsequently into four groups: group 1 (n=19), LV lead placed at the most delayed echocardiographic site in spontaneous rhythm; group 2 (n=25), LV lead placed at any other site; group 3 (n=21), LV lead placed at the most delayed echocardiographic site during right ventricular pacing; group 4 (n=23), LV lead placed at any other site.


RESULTS
No significant differences were observed between the four groups before implantation. After 6 months of CRT, no significant differences were observed between groups 1 and 2 or between groups 3 and 4 in terms of change in New York Heart Association functional class, Minnesota living with heart failure questionnaire, 6-minute walk test, peak exercise oxygen consumption, 3D ventricular dyssynchrony and 3D LV ejection fraction.


CONCLUSIONS
Implantation of the LV lead in the most delayed region of the left ventricle determined by 3D echocardiography did not result in additional improvement in symptoms or LV function.
Service Pr-Clementy, Hôpital Haut-Lévêque, Avenue Magellan, 33600 Pessac, France.
Antoine
A
Deplagne
Stephane
S
Lafitte
Sylvain
S
Reuter
Patricia
P
Reant
Sylvain
S
Ploux
Bilel
B
Mokrani
Raymond
R
Roudaut
Pierre
P
Jais
Michel
M
Haissaguerre
Jacques
J
Clementy
Pierre
P
DosSantos
Pierre
P
Bordachar
D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D019560:Echocardiography, Three-Dimensional; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006329:Heart Conduction System / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010865:Pilot Projects; D011446:Prospective Studies; D020127:Recovery of Function; D012720:Severity of Illness Index; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D016277:Ventricular Function, Left; D016138:Walking