Preoperative endothelial function and long-term cardiovascular events in patients undergoing cardiovascular surgery

We recently reported that preoperative endothelial dysfunction [i.e., reactive hyperemia index (RHI) ≤ 1.64] predicted short-term postoperative adverse events in patients undergoing cardiovascular surgery. However, the relationship between preoperative RHI and long-term cardiovascular risk in these patients is unclear. A total of 195 patients with at least 1-year follow-up who underwent cardiovascular surgery were included. Preoperative endothelial function was assessed by RHI. The primary outcome was a composite of cardiac death, stroke, myocardial infarction, rehospitalization due to heart failure, and any coronary revascularization. Nineteen patients (9.7%) met the primary outcome, including cardiac death (n = 7), stroke (n = 5), heart failure (n = 9), and coronary revascularization (n = 2) during a median follow-up of 20 months. There was no significant difference in the baseline characteristics between patients with RHI ≤ 1.64 (n = 86) and those with RHI > 1.64 (n = 109). The primary outcome occurred in 13 patients with RHI ≤ 1.64 (15.1%) and in 6 patients with RHI > 1.64 (5.5%). Kaplan-Meier analysis demonstrated a significantly higher incidence of the primary outcome in patients with RHI ≤ 1.64 compared to their counterpart (hazard ratio 2.94; 95% confidence interval 1.12-7.75; p = 0.02). Multivariate analysis showed diabetes and RHI ≤ 1.64 as independent predictors for the primary outcome. In conclusion, preoperative endothelial dysfunction assessed by RHI was associated with long-term cardiovascular events in patients undergoing cardiovascular surgery.