Prolonged repolarization after ventricular assist device support is associated with arrhythmias in humans with congestive heart failure.
BACKGROUND
Recent observations indicate that the QTc interval often increases in the early postoperative period (<1 week) after mechanical unloading of severely failing hearts with a left ventricular assist device (LVAD). The present study examined whether early changes in ventricular repolarization after LVAD placement are associated with ventricular arrhythmias.


RESULTS
An electrocardiogram was obtained within 4 days before LVAD placement, <12 hours after LVAD placement, and weekly thereafter. Patient records were reviewed for documented ventricular tachycardia (VT) or ventricular fibrillation (VF) for 1 week preoperatively and the first 2 weeks postoperatively. Differences in QTc interval between patients with and without VT were evaluated. Ten of 17 patients enrolled (59%) had VT or VF after LVAD placement. Of these, 4 required therapeutic intervention because of clinical instability or symptoms. The change in the QTc (DeltaQTc) between the preoperative and immediate postoperative period was significantly different among patients with VT/VF compared with patients without VT/VF (+23 ms vs. -68 ms, P < .001).


CONCLUSIONS
The early period after initiation of LVAD support of the failing human heart is associated with a relatively high incidence of significant ventricular arrhythmias after LVAD placement. Beyond the impact of myocardial inflammation and wound healing occurring after all LVAD implants, early postoperative increases in the QTc interval after cardiac unloading appear to predispose to ventricular arrhythmias.
Harding
John D
JD
Cardiovascular Division, University of Pennsylvania School of Medicine, Philadelphia, PA 19140, USA.
Piacentino
Valentino
V
Rothman
Steven
S
Chambers
Susan
S
Jessup
Mariell
M
Margulies
Kenneth B
KB
D004562:Electrocardiography; D005260:Female; D006333:Heart Failure / Q000601:surgery*; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D011183:Postoperative Complications; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000209:etiology*; D013686:Telemetry; D018487:Ventricular Dysfunction, Left / Q000601:surgery; D014693:Ventricular Fibrillation / Q000209:etiology*