Improved Cardiac MRI Volume Measurements in Patients with Tetralogy of Fallot by Independent End-Systolic and End-Diastolic Phase Selection

Abstract

ObjectivesTo investigate to what extent cardiac MRI derived measurements of right ventricular (RV) volumes using the left ventricular (LV) end-systolic and end-diastolic frame misrepresent RV end-systolic and end-diastolic volumes in patients with tetralogy of Fallot (ToF) and a right bundle branch block.MethodsSixty-five cardiac MRI scans of patients with ToF and a right bundle branch block, and 50 cardiac MRI scans of control subjects were analyzed. RV volumes and function using the end-systolic and end-diastolic frame of the RV were compared to using the end-systolic and end-diastolic frame of the LV.ResultsTiming of the RV end-systolic frame was delayed compared to the LV end-systolic frame in 94% of patients with ToF and in 50% of control subjects. RV end-systolic volume using the RV end-systolic instead of LV end-systolic frame was smaller in ToF (median −3.3 ml/m2, interquartile range −1.9 to −5.6 ml/m2; p<0.001) and close to unchanged in control subjects. Using the RV instead of LV end-systolic and end-diastolic frame hardly affected RV end-diastolic volumes in both groups and ejection fraction in control subjects (54±4%, both methods), while increasing ejection fraction from 45±7% to 48±7% for patients with ToF (p<0.001). QRS duration correlated positively with the changes in the RV end-systolic volume (p<0.001) and RV ejection fraction obtained in ToF patients when using the RV instead of the LV end-systolic and end-diastolic frame (p = 0.004).ConclusionFor clinical decision making in ToF patients RV volumes derived from cardiac MRI should be measured in the end-systolic frame of the RV instead of the LV.

Quality of Life Among Patients With Congenital Heart Disease After Valve Replacement

“…CMR protocols and acquisitions used for assessment of ventricular volume have been previously described by our group in detail. 19,20…”

Assessment of the tricuspid valve using cardiovascular magnetic resonance

“…These values are based off a bSSFP short-axis stack of the ventricles, with a slice thickness of 6-8 mm and an interslice gap of 2-4 mm [1]. End diastolic and end systolic frame selection for the RV can differ from the LV if there are conduction abnormalities, and if not properly accounted for, can result in significant errors in RV volume quantitation [11]. Traditionally, such frame selection was performed manually but recent advances in automated analysis show comparable results [12].…”

Impact of Basal Plane Selection on the Evaluation of Cardiac Performance Parameters with Cardiac Magnetic Resonance Imaging in Patients with Corrected Tetralogy of Fallot: A Systematic Approach

“…Selection of end-diastolic and end-systolic phase was performed manually by visual determination of the cardiac phase with the largest/smallest ventricular cavity. Therefore, a delayed contraction of the right ventricle due to the right branch bundle block was considered (11,12). For the end-diastolic and end-systolic phases, all ventricular contours were drawn manually on the short axis cine stack from the aortic/pulmonary valve to the left ventricular/right ventricular apex, with trabeculation assigned to the blood pool (18)(19)(20).…”

“…When evaluating cardiac performance parameters with the cardiac MRI short axis method, there are some critical picture elements including papillary muscles, determination of the end-diastolic and end-systolic cardiac phase in respect of a probably existing right bundle branch block, and furthermore selection of the basal plane (10)(11)(12)(13). The slice thicknesses routinely acquired are 3 to 6 mm.…”