Larger pulmonary artery to ascending aorta ratios are associated with decreased survival of patients undergoing pulmonary endarterectomy

Panja M Boehm; Stefan Schwarz; Jürgen Thanner; Cecilia Veraar; Mario Gerges; Christian Gerges; Irene Lang; Paul Apfaltrer; Helmut Prosch; Shahrokh Taghavi; Walter Klepetko; Hendrik Jan Ankersmit; Bernhard Moser

doi:10.1016/j.xjon.2022.02.018

Larger pulmonary artery to ascending aorta ratios are associated with decreased survival of patients undergoing pulmonary endarterectomy

JTCVS Open. 2022 Feb 23:10:62-72. doi: 10.1016/j.xjon.2022.02.018. eCollection 2022 Jun.

Authors

Affiliations

¹ Department of Thoracic Surgery, Medical University of Vienna, Vienna, Austria.
² Division of Cardiac Thoracic Vascular Anesthesia and Intensive Care Medicine, Department of Anesthesia, Intensive Care Medicine and Pain Medicine, Medical University of Vienna, Vienna, Austria.
³ Division of Cardiology, Department of Medicine II, Medical University of Vienna, Vienna, Austria.
⁴ Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.

Abstract

Objectives: The ratio of pulmonary artery (PA) and ascending aorta (AA) diameters has recently been shown to be a useful indicator for disease severity and predictor of outcome in patients with pulmonary hypertension and heart failure. This study aimed at evaluating the applicability of this ratio for perioperative risk assessment of patients with chronic thromboembolic pulmonary hypertension undergoing pulmonary endarterectomy.

Methods: In this retrospective cohort study on 149 patients undergoing pulmonary endarterectomy between 2013 and 2020, the preoperative PA to AA ratio was analyzed on axial computed tomography. Variables of pulmonary hemodynamic status were assessed during preoperative right heart catheterization and postoperative Swan-Ganz catheter measurements. Perioperative survival was analyzed by Kaplan-Meier method and log-rank tests.

Results: Preoperative computed tomography measurements showed a median AA diameter of 31 mm (range, 19-47 mm), and a median PA diameter of 36 mm (range, 25-55 mm). The calculated median PA to AA ratio was 1.13 (range, 0.79-1.80). PA to AA ratio correlated positively with PA pressure (systolic, r = 0.352 [P < .001]; diastolic, r = 0.406 [P < .001]; mean, r = 0.318 [P < .001]) and inversely with age (r = -0.484 [P < .001]). Univariable Cox regression analysis identified PA diameter (P = .008) as a preoperative parameter predictive of survival. There was a significant difference (log-rank P = .037) in 30-day survival probability for patients with lower PA to AA ratios (<1.136; survival probability, 97.4%) compared with patients with higher ratios (>1.136; survival probability, 88.9%).

Conclusions: PA to AA ratio shows a correlation with other variables associated with pulmonary hypertension. In addition, patients with higher PA to AA ratios have lower survival probabilities after PEA. Further analysis of PA to AA ratio on the selection of chronic thromboembolic pulmonary hypertension for different treatment modalities-pulmonary endarterectomy, medical therapy, and or balloon pulmonary angioplasty-is warranted.

Keywords: AA, ascending aorta; BPA, balloon angioplasty; CT, computed tomography; CTE, chronic thromboembolic material; CTEPH, chronic thromboembolic pulmonary hypertension; DVT, deep venous thrombosis; PA to AA ratio; PA, pulmonary artery; PAP, pulmonary artery pressure; PE, pulmonary embolism; PEA, pulmonary endarterectomy; PH, pulmonary hypertension; PVR, pulmonary vascular resistance; RA, right atrium; WHO, World Health Organization; WU, Wood Units; chronic thromboembolic pulmonary hypertension; computed tomography; dPAP, diastolic pulmonary artery pressure; mPAP, mean pulmonary artery pressure; pulmonary endarterectomy; pulmonary hypertension; sPAP, systolic pulmonary artery pressure.