Abstract
Objective
Chronic high-altitude exposure has been shown to reduce ischemia-reperfusion injury in animal experiments. The objective was to evaluate the clinical protective effect of long-term high-altitude hypoxic exposure for patients undergoing cardiac surgery with cardiopulmonary bypass.
Methods
In this retrospective cohort study, data from patients who underwent cardiac procedures between January 2013 and December 2019 at a single center was collected. Patients were divided into highlander group (> 2500 m) and lowlander group (< 1500 m) according to the altitude of their residence. A propensity-score-matched analysis was performed to estimate the association of long-term high-altitude exposure and cardiac surgery outcomes.
Results
In a total of 2085 patients, 128 highlander patients were matched to 248 lowlander patients. The levels of CK-MB and hs-TnI upon arrival at the intensive care unit were lower in the highlander group compared to the lowlander group [70.6 U/L (56.0, 92.6) vs 85.0 U/L (68.5, 113.5), P < 0.001; 6.1 ng/mL (3.3,11.2) vs 7.9 ng/mL (3.6, 14.1), P = 0.011, respectively]. The highlander group also had a lower incidence of acute kidney injury (13.3% vs 21.8%, P = 0.046). The in-hospital mortality in the highlander group was lower than in the lowlander group without statistical significance (0.8% vs 4.0%, P = 0.107).
Conclusions
Long-term high-altitude exposure was associated with less myocardial injury and a lower incidence of acute kidney injury after cardiac surgery.
Early Postoperative Statin Therapy Is Associated With a Lower Incidence of Acute Kidney Injury After Cardiac Surgery
