Right ventricular remodelling in systemic hypertension: a cardiac MRI study

Background Consistent evidence shows an impact of systemic haemodynamic overload on the right ventricle, but its functional and structural consequences have received scarce attention for several reasons including the difficult application of conventional imaging techniques due to the complex shape and orientation of that cardiac chamber. Aims To evaluate whether mild to moderate, uncomplicated hypertension associates with abnormal right ventricular structure and function and how those changes relate to homologous changes in the left ventricle. Data were acquired by steady-state free-precession cardiac MRI, the state of the art tool for the morphological and functional evaluation of the right ventricle. Materials and methods Twenty-five (12 women) uncomplicated, untreated, essential hypertensive patients were compared with 24 (13 women) sedentary normotensive controls of comparable age. Wall thickness, indexed ventricular mass, end-diastolic volumes, early peak filling rate, a correlate of diastolic relaxation, and ejection fraction were measured at both ventricles. Remodelling index, the ratio of ventricular mass to end-diastolic volume, was used as an index of concentricity. Results Right ventricular mass index, ventricular wall thickness and remodelling index were greater in hypertensive subjects and associated with reduced peak filling rate, a pattern consistent with concentric right ventricular remodelling. In the hypertensive group, positive, highly significant biventricular correlations existed between indexed mass, early peak filling rate and ejection fraction. Conclusions Systemic hypertension associates with concentric right ventricular remodelling and impaired diastolic function, confirming that the unstressed ventricle is not immune to the effects of systemic hypertension. Structural and functional right ventricular adaptation to systemic hypertension tends to parallel the homologous modifications induced by systemic haemodynamic overload on the left ventricle.