Quantitative analysis of the pulmonary wedge angiogram in congenital heart defects. Correlation with hemodynamic data and morphometric findings in lung biopsy tissue.

SUMMARY At cardiac catheterization, 93 pulmonary wedge angiograms were performed in 85 patients with congenital heart defects. The pulmonary wedge angiogram was quantitatively analyzed and the findings were compared with hemodynamic features and morphometric assessment of lung biopsy tissue when available (27 patients). A pulmonary wedge catheter was directed into the right or left lower lobe to the origin of the posterobasal segment artery. The balloon was inflated and 0.3 mI/kg Renovist injected; then, the balloon was deflated and the venophase was followed. From the cine, the following were assessed: (1) abruptness of tapering of the pulmonary arteries (mean length of the artery segment between luminal diameters of 2.5 mm and 1.5mm was calculated), (2) intensity of background haze with reference to standard films and (3) pulmonary circulation time, i.e., the time from balloon deflation to entrance of Renovist into the left atrium. Progressively more abrupt tapering of the pulmonary arteries was observed in patients with increasingly abnormal hemodynamics (p < 0.001). Four patient groups were significantly different from each other (p < 0.05): group I, normal mean pulmonary artery pressure (Ppa), group II, increased Ppa pulmonary vascular resistance (Rp) ⩽ 3 U/m2, group IIIa, Rp > 3 < 5 U/m2 and group IIIb, Rp ⩾ 5 U/m2. Tapering was also more abrupt with increasingly severe structural changes in lung biopsy tissue (p < 0.001). Those with grade A(abnormal extension of muscle into peripheral arteries), grade B (A + increased medial wall thickness) and grade C (B + reduced artery concentration) were significantly different from each other (p < 0.02). Patients with grade IIIb hemodynamics and grade C lung biopsy changes also differed from all other groups in that they had significantly more reduction in background haze (p < 0.05) and tended to have a more prolonged pulmonary circulation time. After repair, the rate of tapering reflected both the current hemodynamic state as well as preoperative Ppa and lung biopsy findings. Thus, the pulmonary wedge angiogram assessed quantitatively correlates with the hemodynamic findings and is also informative of the structural state of the peripheral pulmonary vascular bed.