Estimated right ventricular systolic time intervals for the assessment of right ventricular function in acute respiratory distress syndrome.
Right ventricular (RV) systolic time intervals (STIs) have been shown to accurately reflect RV function in patients with acute respiratory distress syndrome (ARDS). The measurement of RVSTIs requires phonocardiography to define the time of RV end systole. If RV end-systolic pressure (RVESP) can be derived from peak pulmonary artery (PA) systolic pressure, then the time of RV end systole, and hence, RVSTIs can be deduced without phonocardiography. We tested this possibility. In 34 patients with ARDS, RVESP was determined on the PAP curve at RV end systole, which was defined by phonocardiography. The ratios of RVESP/peak PA systolic pressure were obtained in each patient, the mean of which was 0.90 +/- 0.006. With an application of this value, the estimated RVSTIs were determined in other groups of patients. Right ventricular end-systolic pressure was estimated from the peak PA systolic pressure by multiplying 0.9. Then the point of RV end systole was determined on the electrocardiographic tracing that coincided with the point of RVESP on the PAP curve by simultaneous display of electrocardiograph and PAP curve. Total electromechanical systole was measured from the onset of the QRS complex to the point of RV end systole on the electrocardiograph. The onset of RV ejection was defined by PAP curve. The validity of this estimated RVSTIs was tested by comparing with the measured RVSTIs. By Bland-Altman analysis, the mean difference in RVSTIs between the two methods was 0.007, and bias was 0.0036, suggesting close agreement. The estimated RVSTIs can be used to accurately assess RV function.
Her
Charles
C
Department of Anesthesiology, Westchester Medical Center, Valhalla, NY 10595, USA. charles6133@msn.com
Koike
Hideo
H
O'Connell
James
J
D000328:Adult; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010701:Phonocardiography; D012128:Respiratory Distress Syndrome / Q000473:pathology / Q000503:physiopathology*; D013599:Systole / Q000502:physiology*; D016278:Ventricular Function, Right / Q000502:physiology*; D055815:Young Adult