Association between postoperative exposure to fine particulate matter and patency of the right ventricle-pulmonary artery conduit

Background: Ambient air pollution is a leading risk factor for cardiovascular diseases. No study has investigated the association between exposure to fine particulate matter <2.5 mu m in aerodynamic diameter (PM2.5) and the prognosis of patients undergoing surgery for the right ventricle-pulmonary artery (RV-PA) conduit.Methods: From 2013 to 2020, patients with six complicated congenital heart defects who had undergone surgery for the RV-PA conduit were selected. Four conduit materials were used: bovine jugular vein graft (BJV), pulmonary homograft (PHG), aortic homograft (AHG), and handmade tri-leaflet expanded polytetrafluoroethylene (ePTFE) conduit. Telephone interviews were used to confirm the postoperative address of patients. The monthly average PM2.5 concentration was obtained from the ChinaHighPM(2.5) dataset using the place of residence of patients. By comparing findings of echocardiography undertaken before patients' return to their residence and during re-examination, we defined an increase in the trans-conduit peak velocity of >= 1.5 m/s as the study endpoint.Results: We enrolled 232 patients. Compared with BJV conduits, homografts (AHGs and PHGs) (0.052 (95 % CI = 0.005-0.558), P = 0.015) and ePTFE conduits (0.009 (95 % CI = 0.002-0.054), P < 0.001) were protective factors. The cumulative monthly PM2.5 concentration (10 mu g/m(3)) was a risk factor (1.014 (95 % CI = 1.001-1.026), P = 0.028). Winter experience was a risk factor (1.971 (95 % CI: 1.021-3.804), P = 0.043). In the subgroup analysis, Spearman correlation analysis indicated BJV conduits (r = 0.680, P < 0.001), PHGs (r = 0.559, P = 0.020), and AHGs (r = 0.745, P = 0.021) had medium-to-high positive correlations between the cumulative PM2.5 concentration and change in the conduit velocity. For ePTFE, the correlation was weak and not significant (r = 0.222, P = 0.073).Conclusions: Postoperative exposure to PM2.5 affects the patency of biologic prosthetic conduits (especially xenografts). The increase in the velocity of the ePTFE conduit is not associated with PM2.5 exposure, and is a suitable material for patients living in areas with high pollutant concentrations.