Impaired left ventricular filling due to right-to-left ventricular interaction in patients with pulmonary arterial hypertension.
The aim of this study was to investigate the contribution of direct right-to-left ventricular interaction to left ventricular filling and stroke volume in 46 patients with pulmonary arterial hypertension (PAH) and 18 control subjects. Stroke volume, right and left ventricular volumes, left ventricular filling rate, and interventricular septum curvature were measured by magnetic resonance imaging and left atrial filling by transesophageal echocardiography. Stroke volume, left ventricular end-diastolic volume, and left ventricular peak filling rate were decreased in PAH patients compared with control subjects: 28 +/- 13 vs. 41 +/- 10 ml/m(2) (P < 0.001), 46 +/- 14 vs. 61 +/- 14 ml/m(2) (P < 0.001), and 216 +/- 90 vs. 541 +/- 248 ml/s (P < 0.001), respectively. Among PAH patients, stroke volume did not correlate to right ventricular end-diastolic volume or mean pulmonary arterial pressure but did correlate to left ventricular end-diastolic volume (r = 0.62, P < 0.001). Leftward interventricular septum curvature was correlated to left ventricular filling rate (r = 0.64, P < 0.001) and left ventricular end-diastolic volume (r = 0.65, P < 0.001). In contrast, left atrial filling was normal and not correlated to left ventricular end-diastolic volume. In PAH patients, ventricular interaction mediated by the interventricular septum impairs left ventricular filling, contributing to decreased stroke volume.
Gan
C  Tji-Joong
C
Dept. of Pulmonary Diseases, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
Lankhaar
Jan-Willem
JW
Marcus
J Tim
JT
Westerhof
Nico
N
Marques
Koen M
KM
Bronzwaer
Jean G F
JG
Boonstra
Anco
A
Postmus
Pieter E
PE
Vonk-Noordegraaf
Anton
A
D000328:Adult; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000503:physiopathology*; D013318:Stroke Volume; D018754:Ventricular Dysfunction / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*