MAGNETIC RESONANCE IMAGING IN THE EVALUATION OF IDIOPATHIC FREQUENT PREMATURE VENTRICULAR COMPLEXES

BACKGROUND The value of cardiac magnetic resonance (CMR) imaging in evaluating patients with frequent premature ventricular complexes (PVCs) is uncertain. Prior studies in highly selected populations may overestimate the prevalence of abnormal findings on CMR. This study aimed to: 1) define the prevalence of CMR imaging abnormalities in a cohort with high PVC burden; 2) identify predictors of CMR imaging abnormalities in patients with frequent PVCs. METHODS AND RESULTS 264 patients (age 55.0 ± 16 years; 48% male) with frequent PVCs (≥ 5%/24 h) and no known structural heart disease were prospectively enrolled from 2016-2020. Those with unexplained reduced, global left ventricular function were included, if no other evidence of structural disease was evident on initial work-up. Of these, 202 (77%) patients were symptomatic with palpitations, fatigue, chest pain, dizziness, and/or dyspnea. Patients underwent CMR imaging (1.5 Tesla) with late gadolinium enhancement (LGE) protocol at baseline for the detection of scar/fibrosis. The median baseline echocardiographic left ventricular ejection fraction (LVEF) was 57% (Interquartile Range [IQR] 51-60%) and 240 (91%) had a normal native QRS morphology. Median PVC burden was 17% (IQR 11-25%). CMRs with suboptimal imaging quality were independently adjudicated. CMR LGE was found in 34 (13%), including 27 (10%) with LGE in a non-ischemic distribution and 7 (3%) in an ischemic distribution (occult myocardial infarction). Several predictors were significant univariate but not multivariate predictors of LGE presence, including male sex, history of hypertension, and non-sustained ventricular tachycardia (see Table 1). Significant multivariate predictors were: age ≥ 60 (OR: 5.48 [2.29-13.11]), LVEF CONCLUSION Among patients with apparently idiopathic PVCs on initial workup, 13% demonstrated myocardial abnormalities on CMR imaging. Age ≥ 60 years, LVEF