title: Noninvasive evaluation of the ratio of pulmonary to systemic flow in ventricular septal defect by means of Doppler two-dimensional echocardiography.
abstract: Left ventricular inflow volume (LVIV) and outflow volume (LVOV) were determined by pulsed Doppler echocardiography, and the ratio of pulmonary to systemic flow (Qp/Qs) was estimated as a ratio of LVIV to LVOV (LVIV/LVOV). Seventy-seven patients were studied, 47 control subjects and 30 patients with ventricular septal defect (VSD). LVOV was calculated from the left ventricular ejection flow velocity and left ventricular outflow tract diameter; LVIV was calculated from the transmitral flow velocity and mitral valve motion as traced by M-mode echocardiography. Cardiac input (COin) and cardiac output (COout) were calculated as the product of LVIV or LVOV and heart rate. Cardiac output was also determined by the dye dilution method (COdye) in control subjects. A close correlation was observed between COdye and COin (y = 1.18x - 243, r = 0.85, p less than 0.005, SEE = 1026 ml/min) and COdye and COout (y = 1.16x - 323, r = 0.90, p less than 0.005, SEE = 639 ml/min). LVIV and LVOV were highly correlated in control subjects (y = 0.95x + 5.3, r = 0.94, p less than 0.005, SEE = 6.6 ml). LVIV/LVOV was 0.97 +/- 0.1 (mean +/- SD) in control subjects, whereas LVIV/LVOV (1.87 +/- 0.88) was significantly higher in patients with VSD (p less than 0.01). In patients with VSD, LVIV/LVOV correlated with Qp/Qs determined invasively (y = 0.97, SEE = 0.23, n = 16). Thus with our method LVIV and COin can be accurately determined, and we suggest that Doppler-determined LVIV/LVOV is clinically useful for evaluating the shunt flow magnitude in VSD.
authors.affiliation: Department of Internal Medicine, Kitasato University School of Medicine, Kanagawa, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kurokawa
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: Y
authors.initials: Y
authors.lastname: Katoh
authors.forename: J
authors.initials: J
authors.lastname: Muramatsu
authors.forename: R
authors.initials: R
authors.lastname: Kikawada
mesh_terms: D000328:Adult; D002302:Cardiac Output; D002648:Child; D015150:Echocardiography, Doppler; D005260:Female; D006345:Heart Septal Defects, Ventricular / Q000175:diagnosis* / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D011652:Pulmonary Circulation; D013318:Stroke Volume