Abstract 18228: Non-Invasive Measurements of Coronary Blood Flow Predicts Arrhythmic Events in High-Risk Patients
Introduction: While it is believed that ischemia is an important contributor to arrhythmogenesis including ventricular tachycardia (VT), its role is incompletely understood and remains controversial.
Hypothesis: We hypothesize that abnormal myocardial perfusion as measured by PET imaging is an independent predictor of ventricular tachycardia in a high-risk population.
Methods: Patients with implantable cardiac defibrillators (ICDs) placed for primary and secondary prevention of sudden cardiac death (SCD) who had undergone rubidium-82 cardiac PET imaging were retrospectively identified. The extent and severity of perfusion abnormalities were quantified by visual evaluation of myocardial perfusion images. Rest and stress myocardial blood flows (MBF) and coronary flow reserve (CFR) were computed using kinetic modelling. Device interrogation reports, medical records and death records were reviewed to obtain clinical information. Patients were stratified by median MBF and CFR values for analysis. The Cox proportional hazards model was used to assess the impact of myocardial perfusion on survival free of VT independent of critical covariates.
Results: A total of 121 patients [92 (78.6%) males, average age 63.2 ± 12.2 yrs] were followed for 2.0 ± 1.6 yrs. VT occurred in 29 patients (23.7%). Low resting MBF <1.0 ml/min/g yielded a 3.0-fold increased risk of VT (95% CI 1.3-6.8, P=0.008). Lower resting MBF was associated with higher rates of VT (HR 3.5 per ml/min/g [95% CI 1.2-10.6]; P=0.03) independent of age, sex, race, summed rest score, summed difference score and ejection fraction. After adjustment, neither stress MBF or coronary flow reserve (CFR) were associated with VT (Figure 1: Kaplan-Meier survival analysis of survival free of VT).
Conclusions: In conclusion, we report the novel finding that impaired resting MBF is an independent negative predictor of survival free of VT in high risk patients.
Author Disclosures: M. Ghannam: None. K. Mikhova: None. H. Yun: None. J.J. Lazarus: None. M. Konerman: None. A. Saleh: None. R. Weinberg: None. R. Cunnane: None. R.V. Shah: None. K.M. Hiller: None. E.P. Ficaro: None. J.R. Corbett: None. V.L. Murthy: None.
- © 2016 by American Heart Association, Inc.