Right ventricular regional contraction patterns in normal subjects using cardiac magnetic resonance imaging - a five-year follow up study

Abstract

Methods Subjects (N = 81) were normotensive, non-diabetic, nonobese and without cardiovascular disease screened by history, echocardiography and ECG at baseline. Cardiac MRI was performed using SSFP cine imaging with prospective gating at baseline and retrospective gating at follow up. Variant RV regional contraction patterns were defined as systolic and diastolic focal outpouchings in 4 chamber, short axis, 3 chamber and RV outflow tract views. The length of segments showing focal outpouching and their relationship to the moderator band insertion were determined. We reported findings at 5-year follow up and compared that with baseline findings using repeated measures ANOVA for continuous variables and McNemar's nonparametric test for dichotomous data. Results Mean age at intake was 54 ± 13 years and 44 (54%) were females. Systolic focal outpouching occurred in 33/81 subjects (41%) and 25/33 (75%) occurred at end systole. All 12 instances (15%) of diastolic focal outpouching were found in mid diastole and none at end diastole. Most systolic 20/33 (61%) and diastolic 9/12 (75%) focal outpouchings were related to an insertion site of the moderator band. Mean length of outpouchings was 4.2 ± 2.3 mm. Among all the views analyzed, the 4 chamber view had the highest frequency of outpouching 45/61(74%). Comparing those with and without outpouching there was no difference in RV volume, ejection fraction (EF) or mass (p = NS). Compared to intake there was no difference in the presence, location and dimensions of focal outpouchings at 5-year follow up and no additional outpouchings were present at follow up. There was also no difference in the temporal change in RV volume, EF and mass between groups with and without RV focal outpouching.