Sylvia Abadir1, Charlotte Blanchet2, Anne Fournier2, Wadi Mawad2, Azadeh Shohoudi3, Nagib Dahdah2, Paul Khairy4. 1. Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada. 2. Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada. 3. Montreal Health Innovations Coordinating Center (MHICC), Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada. 4. Division of Cardiology, CHU Mère-enfant Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada; Montreal Health Innovations Coordinating Center (MHICC), Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada. Electronic address: paul.khairy@umontreal.ca.
Abstract
BACKGROUND: There are few data regarding the characteristics of premature ventricular contractions (PVCs) in healthy children and their impact on left ventricular (LV) function. OBJECTIVE: The purpose of this study was to assess the prevalence of LV systolic dysfunction in children with frequent PVCs (≥10%) and determine whether it is associated with PVC characteristics (e.g., proportion, coupling interval, width, and/or morphology). METHODS: We conducted a single-center cohort study of children with structurally normal hearts and PVC burden ≥10% by 24-hour Holter monitoring performed between 2008 and 2012. Clinical, arrhythmic, and echocardiographic data were reviewed at baseline and during follow-up. RESULTS: A total of 47 children (22 female [47%], mean age 8.2 ± 6.5 years) had a mean PVC burden of 20.9 ± 11.9% at baseline. The PVC coupling interval averaged 430 ± 110 ms, with a PVC width of 118 ± 27 ms. PVCs were monomorphic in 44 patients (94%). Although no patient had severe cardiomyopathy, 7 (15%) had reduced shortening fraction (Z-score <-2). A strong association was observed between PVC coupling interval and LV shortening fraction Z-score <-2.0 (area under the curve 0.95 ± 0.03, P <.001). A cutoff value <365 ms yielded the greatest discriminatory ability (Youden J-statistic 0.72, sensitivity 85.7%, specificity 86.5%). PVC proportion, width, and morphology were not significantly associated with LV shortening fraction. During 4.0 ± 2.8 years of follow-up, the PVC burden decreased from a median of 18% to 1.5% (P<.001). CONCLUSION: PVCs in children with structurally normal hearts are associated with a relatively benign course, with spontaneous resolution in most children. Mild LV systolic dysfunction, observed in 15%, is strongly correlated with a shorter coupling interval (<365 ms).
BACKGROUND: There are few data regarding the characteristics of premature ventricular contractions (PVCs) in healthy children and their impact on left ventricular (LV) function. OBJECTIVE: The purpose of this study was to assess the prevalence of LV systolic dysfunction in children with frequent PVCs (≥10%) and determine whether it is associated with PVC characteristics (e.g., proportion, coupling interval, width, and/or morphology). METHODS: We conducted a single-center cohort study of children with structurally normal hearts and PVC burden ≥10% by 24-hour Holter monitoring performed between 2008 and 2012. Clinical, arrhythmic, and echocardiographic data were reviewed at baseline and during follow-up. RESULTS: A total of 47 children (22 female [47%], mean age 8.2 ± 6.5 years) had a mean PVC burden of 20.9 ± 11.9% at baseline. The PVC coupling interval averaged 430 ± 110 ms, with a PVC width of 118 ± 27 ms. PVCs were monomorphic in 44 patients (94%). Although no patient had severe cardiomyopathy, 7 (15%) had reduced shortening fraction (Z-score <-2). A strong association was observed between PVC coupling interval and LV shortening fraction Z-score <-2.0 (area under the curve 0.95 ± 0.03, P <.001). A cutoff value <365 ms yielded the greatest discriminatory ability (Youden J-statistic 0.72, sensitivity 85.7%, specificity 86.5%). PVC proportion, width, and morphology were not significantly associated with LV shortening fraction. During 4.0 ± 2.8 years of follow-up, the PVC burden decreased from a median of 18% to 1.5% (P<.001). CONCLUSION: PVCs in children with structurally normal hearts are associated with a relatively benign course, with spontaneous resolution in most children. Mild LV systolic dysfunction, observed in 15%, is strongly correlated with a shorter coupling interval (<365 ms).