Assessment of Left Ventricular Diastolic Function After Single Lung Transplantation in Patients With Severe Pulmonary Hypertension
Right ventricular pressure overload causes the deformation of the left ventricle by septal flattening toward its cavity, which may result in impaired left ventricular early filling. Recent studies have demonstrated the ability of single lung transplantation to restore right ventricular function in patients with severe pulmonary hypertension. However, changes in left ventricular filling after single lung transplantation have not been well studied. Therefore, this study was designed to evaluate left ventricular filling dynamics before and after lung transplantation using Doppler echocardiography.
Materials and Methods
Between 1991 and 1996, 47 single lung transplantation procedures were performed in 45 consecutive patients at the University of Kentucky Hospital. Clinical diagnoses were severe pulmonary hypertension in 14 patients and end-stage of COPD in the remaining 31. Of the 14 pulmonary hypertension patients, 9 who had complete Doppler echocardiographic examinations preoper-atively and postoperatively were selected for this study. Nine age-matched normal subjects served as a control group. canada viagra
Two-dimensional and Doppler echocardiography was performed in all study patients before, early (<3 months), and late (>1 year) after lung transplantation. Data were recorded on professional videotape and analyzed using a computer-assisted off-line work-station (Version 2.1; TomTec; Boulder, Colo).
Transmitral pulsed Doppler was obtained from an apical four-chamber view with a sample volume at the level of the mitral annulus. Three consecutive Doppler recordings were manually traced using a hand-held cursor, and the following variables were measured: peak early (E) and atrial (A) velocities and integrals (Ei, Ai). Ratio of E/A and atrial filling fraction (Ai/Ai+Ei, AFF) were then calculated. Heart rate was averaged from the previous measurements.