Effects of Chronic Right Ventricular Pressure Overload on Left Ventricular Diastolic Function Jason M. Lazar, MD, Angel R. Flores, MD, Donald J. Grandis, MD, Judith E. Orie, MD, and Douglas S. Schulman, MD Right ventricular (RV) function influences left veb tricular (LV) diastolic filling in various clinical and experimental models. The influence of RV systolic function on LV diastolic performance was exam- ined in patients with severe RV pressure overload. Eighty-two patients with pulmonary vascular or parenchymal disease who were referred for heart- lung or lung transplant evaluation were studied. All patients had radionuclide angiography from which RV ejection fraction and LV peak filling rate were measured. Most patients (n = 51) had right sided cardiac catheterization. In 24 patients (group l), RV ejection fraction was <30%, whereas in 58 (group 2), it was GO%. Mean pulmonary artery pressure was greater in group 1 than in 2 (57 f 18 vs 34 + 20 mm Hg; p eO.0001). Pulme nary artery wedge pressure was also greater in group 1 than in 2 (14 + 9 vs 7 + 2 mm Hg; p <O.OOOl), whereas peak filling rate was decreased (2.18 + 0.88 vs 2.97 + 0.79 en&diastolic volumes/q p <O.OOOl). LV ejection fraction was normal in all patients. There was an inverse relation between RV ejection fraction and pulmonary artery wedge pressure (r = -0.45; p ~0.001; SEE 5.3). There was a direct relation between RV ejection fraction and LV peak filling rate (r = 0.49; p <0.0001; SEE 1.34). In patients with RV pressure overload, RV systolic function is related to LV diastolic perfor- mance. This effect is most likely mediated by ven- tricular interdependence. (AmJCardiol1993;72:1179-1182) From the Sections of Cardiology, Departments of Medicine, Universi- ty of Pittsburgh School of Medicine, and Medical College of Penn- sylvania, Pittsburgh, Pennsylvania. Manuscript received January 19, 1993; revised manuscript received June 21,1993, and accepted June 23. Address for reprints: Douglas S. Schulman, MD, Medical College of Pennsylvania, Allegheny General Hospital, 320 E. North Avenue, Pittsburgh, Pennsylvania 15212. I ncreased right ventricular (RV) afterload adversely affects RV systolic function.lA Due to the pericardi- um and common ventricular septum, alterations in RV size and function may influence left ventricular (LV) diastolic performance.5-7 The effects of acute alterations in loading conditions of the right ventricle on LV dia- stolic filling were studied previously. Experimentally, acute RV volume and pressure overload results in an up- ward and leftward displacement of the LV pressure-vall- ume curve.8-14 Reduced compliance is associated with alterations in septal configuration.15,16 It remains less clear whether abnormal LV diastolic function occurs in the more common clinical setting of chronic RV pres- sure overload.17-22 We sought to determine the relation between RV systolic dysfunction and LV diastolic func- tion in a large series of patients with chronic pulmonary vascular or parenchymal disease. METHODS Patients: We studied 82 consecutive patients (35 male and 47 female; age range 10 to 62 years, mean 39 f 10) with long-standing, advanced pulmonary disease who were referred for heart-lung transplant evaluation. All patients had radionuclide angiography performed ;as part of that evaluation. Primary diagnoses are listed in Table I. Patients were included in the study if they were clinically stable, and had a normal LV ejection fraction and no evidence of coronary artery disease by either his- tory, electrocardiogram or a regional wall motion ib- normality on the radionuclide angiogram. No patient had clinical evidence of mitral regurgitation. All patients were in sinus rhythm or had sinus tachycardia. Medica- tions were not routinely withheld before testing. Radionuclide angiography: Equilibrium radionu- elide angiography was performed in all patients with a standard gamma camera (General Electric Starcam or Picker) equipped with a low-energy, all-purpose, paral- lel-hole collimator according to previously published methods.23 The patients’ red blood cells were labeled with technetium-99m pertechnetate by the in-vivo tech- nique. The camera was positioned in the left anterior oblique position, which provided the best septal separa- tion with 10 to 15” caudal tilt. Gated angiograms were obtained at 32 frames/cardiac cycle. Studies were pro- cessed by 1 observer. A semiautomatic algorithm gener- ated RV systolic and diastolic regions of interest. Tlhe frames were displayed in an endless loop movie format to assist in edge detection. A phase image was generat- ed to aid in separation of the right atrium and ventric.le. From the background-corrected regions of interest, a time-activity curve was created from which RV ejection fraction was calculated. The lower limit of normal RV ejection fraction in our laboratory is 45%. We considler an RV ejection fraction of 30 to 44% indicative of mild RIGHT VENTRICULAR OVERLOAD AND DIASTOLIC FILLING 11:79