Comprehensive monitoring of cardiac remodeling with aortic stroke volume values provided by a phase-contrast MRI sequence

Objectives:Blood pressure (BP) and its changes with antihypertensive therapy are key parameters when monitoring left ventricular (LV) remodeling. This dual cross-sectional and longitudinal MRI study aimed to determine whether this monitoring is enhanced by aortic stroke volume (SV) values provided by a phase-contrast sequence.Methods:The study involved 334 MRI examinations from 247 study participants who had no significant cardiac disease (18-85 years old, 40% with hypertension) and among whom 48 had a 2-4-year MRI follow-up. Left ventricular hypertrophy and concentric geometry were: respectively assessed according to LV mass indexed to body surface area (g/m(2)) and mass/end-diastolic volume ratio (concentric remodeling index); and correlated with vascular parameters involving BP and the indexed SV (ml/m(2)) determined in the ascending aorta with a phase-contrast sequence.Results:Stroke volume was highly variable, ranging from 22 to 74ml/m(2). The best cross-sectional correlates were: mean BPxSV product, reflecting cardiac work, for LV mass (r(2)=0.21); and mean BP/SV ratio, reflecting arterial load, for concentric geometry (r(2)=0.29). These two SV-derived parameters led to more than two-fold enhancements in cross-sectional predictions compared with BP parameters alone, whereas their longitudinal changes over time paralleled those of concentric geometry (P=0.003 for mean BP/SV) and LV mass (P=0.006 for mean BPxSV), suggesting direct links with cardiac remodeling.Conclusion:The determination of aortic SV with a phase-contrast sequence leads to a significant enhancement in the characterization and monitoring of cardiac remodeling.