|| Checking for direct PDF access through Ovid
Left heart disease is associated with left atrial enlargement and is a common cause of pulmonary hypertension (PH). We investigated the relationship between left atrium maximal axial cross-sectional area (LA-MACSA), as measured on chest computed tomography (CT), and PH due to left heart disease (World Health Organization group 2) in patients with right heart catheterization–proven PH.A total of 165 patients with PH who had undergone right heart catheterization with pulmonary artery pressure and pulmonary capillary wedge pressure (PCWP) measurements and nongated chest CTs were included. LA-MACSA, LA anterior-posterior, and LA transverse measurements were independently obtained using the hand-drawn region-of-interest and distance measurement tools on standard PACS by 2 blinded cardiothoracic radiologists. Nonparametric statistical analyses and receiver operating characteristic curve were performed.Forty-three patients had group 2 PH (PCWP>15 mm Hg), and 122 had nongroup 2 PH (PCWP≤15 mm Hg). Median LA-MACSA was significantly different between the group 2 PH and nongroup 2 PH patients (2312 vs. 1762 mm2, P<0.001). Interobserver concordance correlation for LA-MACSA was high at 0.91 (P<0.001). At a threshold of 2400 mm2, LA-MACSA demonstrated 93% specificity for classifying group 2 PH (area under the curve, 0.73; P<0.001).LA-MACSA is a readily obtainable and reproducible measurement of left atrial enlargement on CT and can distinguish between group 2 and nongroup 2 PH with high specificity.