ASSESSMENT OF LEFT-VENTRICULAR DIASTOLIC FUNCTION AFTER SINGLE-LUNG TRANSPLANTATION IN PATIENTS WITH SEVERE PULMONARY-HYPERTENSION

Objectives: This study was designed to observe left ventricular fillin g by Doppler echocardiography before and after single lung transplanta tion in patients with severe pulmonary hypertension. Background: Right ventricular pressure overload causes the deformation of the left vent ricle by septal flattening toward its cavity, which may result in impa ir ed left ventricular early filling. Recent studies have demonstrated the ability of single lung transplantation to restore right ventricul ar function in patients with severe pulmonary hypertension. However, c hanges in left ventricular filling after single lung transplantation h ave not been well studied. Methods: We performed Doppler echocardiogra phy in nine patients with severe pulmonary hypertension before, early (<3 months), and late (>1 year) after single lung transplantation. The study group consisted of eight female patients and one male patient w ith mean age of 32 years (range, 15 to 48 years). Six patients were di agnosed as having primary pulmonary hypertension and three as having s econdary pulmonary hypertension. Nine age-matched normal subjects serv ed as a control group. Doppler measurements included the following: tr ansmitral flow early (E) and atrial (A) velocities, integrals (Ei and Ai), and left ventricular isovolumic relaxation time. The ratio of E/A and atrial filling fraction (Ai/Ei+Ai, AFF) were also determined. Lef t ventricular geometry was assessed from mid-short axis view with a ci rcular shape factor (CSF), Results: Early after lung transplantation, the left ventricular geometry became more circular with CSF (mean+/-SD ) increasing from 0.63+/-0.09 to 0.88+/-0.05 (p<0.05). However, impair ed early filling persisted in the patient group (E/A 0.7+/-0.1 vs preo perative 0.6+/-0.1, AFF 0.61+/-0.1 vs 0.64+/-0.1; both p = not signifi cant). One year later, the left ventricular filling had returned to no rmal range with E/A 1.4+/-0.6 and AFF 0.35+/-0.1. Conclusions: This st udy observed that the impaired left ventricular early filling persiste d shortly after single lung transplantation in patients with severe pu lmonary hypertension, despite findings that left ventricular geometry was restored earlier after reversal of pulmonary hypertension. The abn ormal filling pattern appeared to be resolved 1 year later. The findin gs suggest the impaired early filling may be caused by intrinsic left ventricular abnormalities other than ventricular interaction in these patients.