Determination of right ventricular ejection fraction by thermodilution catheter technique during exercise: a comparison with radionuclide ventriculography

Since the development of a Swan-Ganz Thermodilution Ejection Fraction Catheter, several studies have been published which compare this technique for obtaining right ventricular ejection fraction (RVEFTD) with alternative methods. However, the reliability of RVEFTD measurements under exercise conditions remains undetermined. Therefore, the aim of the present study was to evaluate RVEFTD with the Gated Blood Pool method (RVEFGBP) under exercise conditions. Twenty patients with different cardiac diseases (coronary artery disease, valvular incompetence, cardiomyopathy) underwent right heart catheterization, 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/m2, 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 RVEFTD and RVEFGBP at rest (r = 0.72, p < or = 0.0005) and during exercise (r = 0.72, p < or = 0.0005). It is concluded that the Thermodilution Ejection Fraction Catheter is a useful device for reliable, repetitive and safe RVEF measurements, not only at rest but also under exercise conditions. This is clinically important, because RVEF, as a sensitive parameter of primary or secondary right ventricular dysfunction, can be determined in the course of standard right heart catheterization.