MRI COMPLEMENTS STANDARD ASSESSMENT OF RIGHT-VENTRICULAR FUNCTION AFTER LUNG TRANSPLANTATION

Background. Changes in right ventricular mass and ejection fraction af ter single-lung transplantation for pulmonary hypertension are poorly understood. Methods. To complement functional data provided by echocar diography, radionuclide ventriculography, and right heart catheterizat ion, magnetic resonance imaging was used to assess right ventricular f unction in 5 single-lung transplant recipients with preoperative pulmo nary hypertension and right ventricular dysfunction (right ventricular ejection fraction, 0.21 +/- 0.09). The right and left ventricular mas s, ejection fraction, and mass ratio (left ventricular mass/right vent ricular mass) were calculated from the magnetic resonance images. Resu lts. The mean pulmonary artery pressure fell from 72 +/- 18 to 21 +/- 8 mm Hg after transplantation. At 3 months after transplantation both the left ventricular and right ventricular ejection fractions approach ed normal values, as shown by both radionuclide ventriculography and m agnetic resonance imaging, but the right ventricular mass remained abn ormally high with slightly low mass ratios. By 1 year both the left ve ntricular and right ventricular masses had regressed to normal with ne ar-normal mass ratios. Conclusions. Right ventricular performance retu rns to nearly normal early after transplantation, but the right ventri cular mass regresses over a more prolonged time. Cine magnetic resonan ce imaging provides a noninvasive means of assessing changes in right ventricular function and mass after lung transplantation.