Thermodilution measurement of right ventricular ejection fraction with a modified pulmonary artery catheter

Abstract

In 14 critically ill patients in stable cardiopulmonary status, right ventricular ejection fraction (RVEF) was measured by thermodilution technique and by radionuclear (gated first pass) technique. The pulmonary artery catheter was equipped with a fast-response thermistor and an intracardiac ECG monitor. In addition, the proximal lumen ended in a 3-hole port 21 cm from the tip of the catheter to facilitate mixing of the cold bolus above the tricuspid valve. The use of a new algorithm based on an exponential curve analysis of the thermodilution curve limited the variability of RVEF determinations to 7.6%. The correlation between RVEF measured by thermodilution and radionuclear techniques was significant (y = 12.7 +/- 0.49x, r = 0.67, p less than 0.01). However, the values obtained by thermodilution were usually lower, especially for high RVEF. Nevertheless, although some discrepancy was found, thermodilution techniques allow simple, accurate and repetitive bedside measurements of right ventricular volumes in the critically ill.

Sepsis and the Heart

“…[23][24][25][26] However, the relative contribution of the right ventricle to septic cardiomyopathy remains unknown.…”

Single-beat estimation of right ventricular end-systolic pressure-volume relationship

“…RV pressure was monitored with a micromanometer catheter (Millar Instruments; Houston, TX) and instantaneous pulmonary blood flow with a transit-time ultrasonic flow probe (Transonic Systems; Ithaca, NY). Cardiac output and RV ejection fraction were measured with a fast-response thermodilution pulmonary artery catheter (Baxter-Edwards; Irvine, CA) (30). A clamp was placed around the pulmonary artery upstream from the flow probe, ϳ1 cm away from the pulmonary valve.…”

Comparative Assessment of Right Ventricular Volumes and Ejection Fraction by Thermodilution and Magnetic Resonance Imaging in Dilated Cardiomyopathy

“…Calculation of the ratio between the tempera ture decreases of two successive diastolic plateaus yields an estimate of the residual fraction (RF) of the RV. The EF is then calculated as: EF = 1 -RF [5,6,14], Cardiac output is calculated from the same pulmonary artery temperature curve by using the Stewart-Hamilton equation [14] and cardiac output divided by heart rate yields the stroke volume (SV). Using heart rate and EF.…”

“…Several studies comparing thermodilution measurements with bi plane angiographic data showed the usefulness of this method for the determination of RV volumes and EF in Received: August 22. 1994 Accepted: September 7.1994 patients with various cardiac diseases [5][6][7], However, limitations of angiographic RV volume measurements include impaired sharpness of ventricular contours due to trabeculations, variable spatial orientation of the RV, and the lack of a single geometric reference model to fit all possible ventricular shapes [8,9], Magnetic resonance imaging (MRI) can be regarded as an alternative imaging modality allowing volume quantif ication of both the RV and the LV and is now being con sidered as the gold standard for volume quantification in vivo [10][11][12], Thus, the purpose of our study was to validate the accuracy of a thermodilution technique for RV volume quantification using simultaneous MRI in patients with dilated cardiomyopathy.…”