Thermodilution left-sided cardiac output for valve area determination after balloon mitral valvotomy.
This study was conducted to establish the validity of left-sided cardiac output measurement with a Swan-Ganz catheter and assess its accuracy in estimating mitral valve area (MVA) by the Gorlin formula. The use of right-sided cardiac output after balloon mitral valvotomy (BMV) can give inaccurate measurements for Gorlin-derived MVA because of the atrial septal defect (ASD) created during the procedure. The left-sided cardiac output was measured with a Swan-Ganz catheter (proximal port in the left atrium and then in the left ventricle, and distal port in the ascending aorta) in 10 consecutive patients before and after BMV. Gorlin-derived MVA cardiac output by this method was compared with (1) Gorlin-derived MVA by means of right-sided cardiac output with and without balloon occlusion of the ASD and (2) MVA measured by echocardiography. Before BMV, a close agreement with a good correlation between left-sided and right-sided cardiac output was found (r = 0.83, p = 0.006). Furthermore, Gorlin-derived MVA by cardiac output with either method was comparable with valve area by echo. After BMV, left-sided cardiac output correlated well (r = 0.92, p = 0.0002) and was comparable with right-sided cardiac output with occlusion of the ASD (mean difference 0.17 +/- 0.49 L/min, p = 0.3) but was significantly lower than the value obtained with open ASD (mean difference 0.93 +/- 0.77 L/min, p = 0.004). Comparison of the correspondent MVAs yielded similar results. Gorlin-derived MVA with left-sided cardiac output and MVA by echo were also similar.(ABSTRACT TRUNCATED AT 250 WORDS)
Gamra
H
H
Department of Cardiology, Loma Linda University Medical Center, CA 92354-0200.
Zhang
H P
HP
Clugston
R A
RA
Whittaker
P
P
Allen
J W
JW
Lau
F Y
FY
Ruiz
C E
CE
D002302:Cardiac Output / Q000502:physiology*; D002404:Catheterization; D002407:Catheterization, Swan-Ganz; D015150:Echocardiography, Doppler; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000503:physiopathology; D008946:Mitral Valve Stenosis / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D012044:Regression Analysis; D015203:Reproducibility of Results; D013815:Thermodilution / Q000295:instrumentation / Q000379:methods