Ambulatory Cardiology or General Internal Medicine Assessment Before Scheduled Major Vascular Surgery Is Associated with Improved Outcomes

Abstract

Objective: To characterize the association between ambulatory cardiology or general internal medicine (GIM) assessment before surgery and outcomes after scheduled major vascular surgery.

Background: Cardiovascular risk assessment and management before high-risk surgery remains an evolving area of care.

Methods: This is a population-based retrospective cohort study of all adults who underwent scheduled major vascular surgery in Ontario, Canada, from April 1, 2004 to March 31, 2019. Patients who had an ambulatory cardiology and/or GIM assessment within 6 months before surgery were compared with those who did not. The primary outcome was 30-day mortality. Secondary outcomes included: composite of 30-day mortality, myocardial infarction or stroke, 30-day cardiovascular death, 1-year mortality, composite of 1-year mortality, myocardial infarction or stroke, and 1-year cardiovascular death. Cox proportional hazard regression using inverse probability of treatment weighting was used to mitigate confounding by indication.

Results: Among 50,228 patients, 20,484 (40.8%) underwent an ambulatory assessment before surgery: 11,074 (54.1%) with cardiology, 8071 (39.4%) with GIM, and 1339 (6.5%) with both. Compared with patients who did not, those who underwent an assessment had a higher Revised Cardiac Risk Index [N with Index over 2 = 4989 (24.4%) vs 4587 (15.4%), P < 0.001] and more frequent preoperative cardiac testing [N = 7772 (37.9%) vs 6113 (20.6%), P < 0.001], but lower 30-day mortality [N = 551 (2.7%) vs 970 (3.3%), P < 0.001]. After the application of inverse probability of treatment weighting, cardiology or GIM assessment before surgery remained associated with a lower 30-day mortality [weighted hazard ratio (95% CI) = 0.73 (0.65-0.82)] and a lower rate of all secondary outcomes.

Conclusions: Major vascular surgery patients assessed by a cardiology or GIM physician before surgery have better outcomes than those who are not. Further research is needed to better understand potential mechanisms of benefit.

Keywords: aortic aneurysm; cardiovascular assessment; peripheral artery disease; vascular surgery.