Biventricular function in patients with nonischemic right ventricle tachyarrhythmias assessed with MR imaging

OBJECTIVE. The purpose of this study was to assess the value of MR imaging in the evaluation of biventricular systolic and right ventricle diastolic function in patients with nonischemic right ventricle tachyarrhythmias. SUBJECTS AND METHODS. Fifteen patients with nonischemic tachyarrhythmias of right ventricle origin as documented by electrophysiologic testing and nine age-matched healthy volunteers underwent volumetric gradient-echo MR imaging of both ventricles to measure global systolic function. Patients and volunteers also underwent MR velocity mapping of transtricuspid flow to measure diastolic right ventricle function. RESULTS. In the patient group, systolic function parameters of both ventricles were in the normal range. Tricuspid flow patterns indicated a significant decrease in peak filling rate (p = .002) and in the slope of the descending part of the early filling phase (p = .009). The ratio of peak early filling rate to peak atrial contraction and ratio of integrated early filling to integrated atrial contraction (i.e., volume) were significantly lower in patients than in healthy volunteers (p = .02 and p = .03, respectively). CONCLUSION. Diastolic right ventricle function is significantly altered in patients with nonischemic tachyarrhythmias of right ventricle origin, but systolic function is preserved. MR imaging is well suited to quantify abnormal right ventricle diastolic function, a possible marker of early cardiac disease.