Impaired hyperemic myocardial blood flow was significantly associated with ventricular arrhythmia inducibility in patients with ischemic cardiomyopathy (AUC 0.84; 95% CI 0.69-0.99).
Observational (n=30)
Is impaired hyperemic myocardial blood flow associated with ventricular arrhythmia inducibility in patients with ischemic cardiomyopathy?
Impaired hyperemic myocardial blood flow and coronary flow reserve assessed by PET are associated with ventricular arrhythmia inducibility in ischemic cardiomyopathy, suggesting a potential role for perfusion imaging in risk stratification.
Effect estimate: AUC 0.84 (95% CI 0.69-0.99)
Absolute Event Rate: 1.25% vs 1.66%
p-value: p=<0.01
BACKGROUND: Risk stratification for ventricular arrhythmias (VAs) is important to refine selection criteria for primary prevention implantable cardioverter defibrillator therapy. Impaired hyperemic myocardial blood flow (MBF) is associated with increased mortality rate in ischemic and nonischemic cardiomyopathy, which may be attributed to electric instability inducing VAs. The aim of this pilot study was to assess whether hyperemic MBF impairment may be related with VA inducibility in patients with ischemic cardiomyopathy. METHODS AND RESULTS: Thirty patients with ischemic cardiomyopathy referred for primary prevention implantable cardioverter defibrillator implantation were prospectively included (26 men; 65±8 years old; left ventricular ejection fraction, 29±6%). 15OH2O positron-emission tomography was performed to quantify resting MBF, hyperemic MBF, and coronary flow reserve. Left ventricular dimensions, function, and scar burden were assessed with cardiovascular magnetic resonance imaging. An electrophysiological study was performed to test VA inducibility. Positive electrophysiological study patients (n=12) showed reduced hyperemic MBF (1.25±0.30 versus 1.66±0.38 mL·min(-1)·g(-1); P75% transmurality was higher (P<0.05), although scar size and border zone did not differ. Receiver-operating characteristic curve analysis indicated that impaired hyperemic MBF (area under the curve, 0.84; 95% confidence intervals 0.69-0.99) and coronary flow reserve (area under the curve, 0.77; 95% confidence intervals 0.57-0.96) were associated with VA inducibility. CONCLUSIONS: In this pilot study, impaired hyperemic MBF and coronary flow reserve were associated with VA inducibility in patients with ischemic cardiomyopathy. These results are hypothesis generating for a potential role of quantitative positron-emission tomography perfusion imaging in risk stratification for VAs.
Rijnierse et al. (Tue,) conducted a observational in Ischemic cardiomyopathy (n=30). Positive electrophysiological study (VA inducibility) vs. Negative electrophysiological study was evaluated on Hyperemic myocardial blood flow (mL·min(-1)·g(-1)) (AUC 0.84, 95% CI 0.69-0.99, p=<0.01). Impaired hyperemic myocardial blood flow was significantly associated with ventricular arrhythmia inducibility in patients with ischemic cardiomyopathy (AUC 0.84; 95% CI 0.69-0.99).