Incidence of and outcomes associated with ventricular tachycardia or fibrillation in patients undergoing primary percutaneous coronary intervention.
BACKGROUND
The incidence and timing of sustained ventricular tachycardia or fibrillation (VT/VF) and its impact on outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) are poorly understood.


OBJECTIVE
To evaluate the association of sustained VT/VF and its timing on the outcomes of patients presenting for primary PCI-an aim not prespecified in the APEX AMI trial.


METHODS
We studied 5745 STEMI patients presenting for primary PCI at 296 hospitals in 17 countries between July 13, 2004, and May 11, 2006, from the APEX AMI trial. We categorized them into 4 groups: no VT/VF; VT/VF any time; early VT/VF, before the end of cardiac catheterization; and late VT/VF, after the end of cardiac catheterization.


METHODS
Ninety-day total mortality.


RESULTS
VT/VF occurred in 329 STEMI patients (5.7%) presenting for primary PCI. The majority of these occurred before the end of catheterization (n = 205, 64%), and 90% occurred within 48 hours of presentation with symptoms of STEMI. Clinical outcomes were worse in patients with vs those without VT/VF (90-day mortality, 23.2% vs 3.6%; adjusted HR, 3.63; 95% CI, 2.59-5.09), and outcomes were worse if the VT/VF occurred late instead of early (90-day mortality for early VT/VF, 17.2% [adjusted HR, 2.34; 95% CI, 1.44-3.80]; for late VT/VF, 33.3% [adjusted HR, 5.59; 95% CI, 3.71-8.43]; for no VT/VF, 3.6% [referent]). In multivariate analyses, factors associated with early VT/VF included pre-PCI thrombolysis in MI (TIMI) flow grade 0 (HR, 2.94; 95% CI, 1.93-4.47), inferior infarction (HR, 2.16; 95% CI, 1.58-2.93), total baseline ST deviation (HR, 1.39; 95% CI, 1.19-1.63), creatinine clearance (HR, 0.88; 95% CI, 0.83-0.94), Killip class greater than I (HR, 1.88; 95% CI, 1.29-2.76), baseline systolic blood pressure (HR, 0.92; 95% CI, 0.87-0.98), body weight (HR, 1.16; 95% CI, 1.04-1.29), and baseline heart rate greater than 70/min (HR, 1.10; 95% CI, 1.01-1.20) (c index, 0.75). Factors related to late VT/VF were systolic blood pressure (HR, 0.83; 95% CI, 0.76-0.91), ST resolution less than 70% (HR, 3.17; 95% CI, 1.60-6.28), baseline heart rate greater than 70/min (HR, 1.20; 95% CI, 1.08-1.33), total baseline ST deviation (HR, 1.43; 95% CI, 1.14-1.79), post-PCI TIMI flow less than grade 3 (HR, 2.09; 95% CI, 1.24-3.52), pre-PCI TIMI flow grade 0 (HR, 2.12; 95% CI, 1.20-3.75), and beta-blockers less than 24 hours (HR, 0.52; 95% CI, 0.32-0.85) (c index, 0.74).


CONCLUSIONS
In this study, occurrence of VT/VF before or after the end of cardiac catheterization in patients presenting for primary PCI was associated with increased 90-day mortality.
Mehta
Rajendra H
RH
Duke Clinical Research Institute, Box 17969, Durham, NC 27715, USA. mehta007@dcri.duke.edu
Starr
Aijing Z
AZ
Lopes
Renato D
RD
Hochman
Judith S
JS
Widimsky
Petr
P
Pieper
Karen S
KS
Armstrong
Paul W
PW
Granger
Christopher B
CB
D017677:Age Distribution; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000401:mortality / Q000628:therapy; D011379:Prognosis; D016016:Proportional Hazards Models; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000453:epidemiology / Q000209:etiology*; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000453:epidemiology / Q000209:etiology*