Autonomic Vulnerability, Intraoperative Hypotension Burden, and Myocardial Injury After Noncardiac Surgery in Older Adults: A Propensity Score-Matched Retrospective Cohort Study.

BACKGROUND

Myocardial injury after noncardiac surgery (MINS) is common and often clinically silent. Older adults with diabetes mellitus (DM) and/or hypertension (HTN) may have autonomic dysfunction that impairs hemodynamic compensation during surgical stress. We hypothesized that a preoperatively identifiable autonomic vulnerability phenotype would be associated with adjudicated ischemic MINS after major noncardiac surgery and that this association would be amplified at higher intraoperative hypotension (IOH) burden.

METHODS

In this single-center retrospective cohort study, patients aged ≥65 years undergoing major noncardiac surgery with perioperative high-sensitivity cardiac troponin T (hs-cTnT) surveillance were analyzed. Autonomic vulnerability was defined as DM and/or HTN plus documented neuropathy, orthostatic hypotension or syncope/presyncope, or unexplained resting bradycardia/chronotropic incompetence. Propensity score matching (1:1) balanced measured confounders. The primary outcome was adjudicated ischemic MINS. Secondary outcomes included postoperative hs-cTnT elevation, 30-day major adverse cardiac events (MACE), 1-year all-cause mortality, and IOH effect modification.

RESULTS

Among 2184 eligible patients, 612 matched pairs were analyzed. MINS occurred in 87 of 612 patients (14.2%) in the autonomic vulnerability group and 53 of 612 (8.7%) in the control group (odds ratio [OR], 1.75; 95% confidence interval [CI], 1.23-2.49; P = .002). Postoperative hs-cTnT elevation was also more frequent (27.1% vs 18.5%; OR, 1.63; 95% CI, 1.28-2.07; P < .001). Thirty-day MACE (hazard ratio [HR], 1.68; 95% CI, 1.12-2.51; P = .012) and 1-year mortality (HR, 1.54; 95% CI, 1.07-2.22; P = .020) were increased. IOH burden modified the autonomic vulnerability-MINS association (P for interaction = .018), with the highest excess risk in the highest IOH quartile (OR, 2.84; 95% CI, 1.62-4.97; P < .001).

CONCLUSIONS

In older adults undergoing major noncardiac surgery, a preoperative electronic health record-based autonomic vulnerability phenotype was associated with higher risk of adjudicated ischemic MINS, and this association was stronger at higher IOH burden. These hypothesis-generating findings require external validation with formal autonomic testing.