Thermodilution measurements of right ventricular ejection fraction during exercise: a comparison with the Gated Blood Pool method

Since the development of a Swan-Ganz Thermodilution Ejection Fraction Cathe ter, several studies have been published which compare this technique for o btaining right ventricular ejection fraction (RVEFTD) with alternative meth ods. However, the reliability of RVEFTD measurements under exercise conditi ons remains undetermined. Therefore, the aim of the present study was to ev aluate RVEFTD with the Gated Blood Poor method (RVEFGBP) under exercise con ditions. Twenty patients with different cardiac diseases (coronary artery d isease, valvular incompetence, cardiomyopathy) underwent right heart cathet erization, including RVEFTD and simultaneous RVEFGBP determination at rest and during supine bicycle exercise. Cardiac index at rest-/exercise was 2.9 +/- 0.8/5.7 +/- 2.2 l/min/m(2), mean pulmonary artery pressure was 15+/-5/ 25+/-8 mmHg, RVEFTD was 38 +/- 6/41 +/- 11% and RVEFRNV was 39 +/- 6/43 +/- 8%. Linear regression analysis showed a significant correlation between RV EFTD and RVEFGBP at rest (r=0.72, p less than or equal to0.0005) and during exercise (r = 0.72, p less than or equal to 0.0005). It is concluded that the Thermodilution Ejection Fraction Catheter is a useful device for reliab le, repetitive and safe RVEF measurements, not only at rest but also under exercise conditions. This is clinically important, because RVEF, as a sensi tive parameter of primary or secondary right ventricular dysfunction, can b e determined in the course of standard right heart catheterization.