Prediction of outcome of patients with life-threatening ventricular arrhythmias treated with automatic implantable cardioverter-defibrillators using SPECT perfusion imaging
Gioia, G.; Bagheri, B.; Gottlieb, C.D.; Schwartzman, D.S.; Callans, D.J.; Marchlinski, F.E.; Heo, J.; Iskandrian, A.E.
Circulation 95(2): 390-394
1997
ISSN/ISBN: 0009-7322 PMID: 9008454 Document Number: 480443
Background: In the present study, we examined the predictors of outcome of 103 patients with coronary artery disease and left ventricular dysfunction who had life-threatening ventricular arrhythmias and were treated with implantable cardioverter-defibrillators with the use of single-photon emission computed tomography (SPECT). Methods and Results: During a mean follow-up of 29 months, there were 29 cardiac deaths. In comparison with patients who died, survivors had less diabetes mellitus (45% versus 19%, P lt .007), higher left ventricular ejection fraction (23 +-9% versus 27+-11%, P=.04), and fewer perfusion defects as determined with stress SPECT (15+-5 versus 12+-5. P lt .004). Most of the perfusion defects were fixed, indicative of scarring; the extent of reversible defects did not differ (2+-3 in survivors and 3+-4 in nonsurvivors). Multivariate Cox survival analysis identified the number of fixed defects as the only independent predictor of death (chi-2=10, P=.002). There were six deaths among 42 patients (14%) with lt 8 fixed defects compared with 23 deaths among 61 patients (38%) with gtoreq 8 defects (P=.005). The 4-year survival was better in patients with lt 8 segmental fixed defects than in those with gtoreq 8 fixed defects (80% versus 36%) (chi-2=8, P=.005). Conclusions The myocardial perfusion pattern is an important determinant of outcome in patients with life-threatening ventricular arrhythmias who are treated with a implantable cardioverter-defibrillator. The extent of scarring separates patients into high- and low-risk groups with a 2.7-fold difference in death rate.