title: Right Ventricular Apical Flattening as an Echocardiographic Screening Tool for Right Ventricular Enlargement.
abstract: Right ventricular dilation is a common complication after tetralogy of Fallot (TOF) repair. Traditional echocardiographic assessments are imprecise due to the RV's location and complex geometry. We propose a novel echocardiographic measurement: RV apical flattening (RVAF) as a screening tool to help identify subjects with severe RV dilation. Patients with repaired TOF who had both echocardiograms and CMR's within 6-month interval at our institution were included in the study. The RVAF was measured in the four-chamber echocardiographic view as the minor length of RV cavity at the level of RV apical endocardium. Subjects were divided into two groups (group I: RVEDVi ≥ 150 ml/m(2) and group II; RVEDVi < 150 ml/m(2)). Echocardiogram and CMR data were compared between groups. A total of 75 subjects were included in the study. Mean age was 12.8 ± 3.6 years. Group I had 36 subjects, and group II had 39 subjects. The mean RVAF was significantly higher in group I (2.7 ± 0.5 cm) compared with group II (1.7 ± 0.4 cm; p < 0.001). There was significant correlation between RVAF and RVEDVi (r = 0.81; p < 0.001). By ROC analysis, an RVAF cutoff value of 2.0 cm had 94 % sensitivity and 77 % specificity in identifying severe RV dilation (area under the curve 0.95). RVAF is a simple and effective echocardiographic screening tool to help identify severe RV dilation. In conjunction with other 2D echocardiographic parameters, this technique would help further refine echocardiography-guided patient selection for timing of CMR and pulmonary valve replacement.
authors.affiliation: Division of Cardiology, Department of Pediatrics, Seattle Children's Hospital, University of Washington School of Medicine, 4800 Sand Point Way NE, Seattle, WA, 98105, USA. drbuddhe@gmail.com.
authors.forename: Sujatha
authors.initials: S
authors.lastname: Buddhe
authors.affiliation: Division of Radiology, Department of Pediatrics, Seattle Children's Hospital, University of Washington School of Medicine, Seattle, WA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Ferguson
authors.affiliation: Division of Cardiology, Department of Pediatrics, Seattle Children's Hospital, University of Washington School of Medicine, 4800 Sand Point Way NE, Seattle, WA, 98105, USA.
authors.forename: Bhawna
authors.initials: B
authors.lastname: Arya
authors.affiliation: Division of Cardiology, Department of Pediatrics, Seattle Children's Hospital, University of Washington School of Medicine, 4800 Sand Point Way NE, Seattle, WA, 98105, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Soriano
mesh_terms: D000293:Adolescent; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002648:Child; D004452:Echocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006776:Hospitals, Pediatric; D006801:Humans; D017380:Hypertrophy, Right Ventricular / Q000000981:diagnostic imaging* / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D011665:Pulmonary Valve Insufficiency / Q000000981:diagnostic imaging* / Q000209:etiology; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013771:Tetralogy of Fallot / Q000601:surgery*; D018497:Ventricular Dysfunction, Right; D014861:Washington
keywords: Cardiac MRI; Dilation; Echocardiogram; Right ventricle; Tetralogy