Prospective comparison of circumferential and longitudinal strain in asymptomatic children with single left ventricle, single right ventricle and normal hearts

Abstract

Background Ventricular dysfunction in patients with a single right ventricle (SRV) or as ingle left ventricle (SLV) is a known risk factor for morbidity and mortality. However, the differences in SRV and SLV function remain poorly understood, with only a few studies performed1-3. In this study, we measure the strain using cardiac MRI and perform comprehensive comparison of the global and regional strain in both the circumferential (ecc) and longitudinal (eL) dimension. Purpose: In normal subjects and asymptomatic patients with SLV and SRV after total cavopulmonary connection (TCPC), compare: 1) Global ecc and eL strain, 2) Regional circumferential and longitudinal strains at free wall (ecc-free, eL-free) and septum (ecc-sept, eL-sept), 3) ecc and eL across the ventricle from apex to base. Methods We performed a prospective analysis of 18 subjects (7 normal age: 11.8 +/- 3; 6 SRV age: 11.4 +/- 2.3; 5 SLV age: 12.7 +/- 4.2). Acquisition Protocol: Strain information was acquired at three short axis slices at basal, mid-cavity, and apical locations in all 18 subjects in a 1.5T MRI scanner (Philips Acheiva) using: a) Complementary Spatial Modulation of Magnetization (CSPAMM)4 images: Used for generating ecc; and b) Fast-Strain Encoded (fSENC)5 images: Used for generating eL. Data Analysis: ecc and eL across all cardiac phases and slices were calculated from SAX slices using DiagnosoftTM. The ventricular regions at each slice were assigned based upon the AHA 16 segment model. ecc-sept, eL-sept, ecc-free, and eL-free were also calculated for each slice and compared. Results