Shorter perioperative QRS duration and a leftward frontal-plane QRS axis are associated with anastomotic leakage after esophagectomy: a hypothesis-generating study

Background Anastomotic leakage (AL) after esophagectomy is a serious complication for which early physiological signals remain limited. We conducted a hypothesis-generating analysis of whether routinely reported electrocardiographic QRS measurements were associated with AL during the perioperative period. Methods This single-center retrospective cohort included 292 of 1,441 patients undergoing esophagectomy who had an index 12-lead electrocardiogram (ECG) from day −1 through postoperative day 1. ECG acquisition followed routine clinical practice rather than a study protocol. QRS duration and frontal-plane QRS axis were retained after descriptive screening of the continuous ECG measurements available in the analytic extract. They were entered into a two-variable logistic model, followed by a sensitivity model additionally adjusting for seven clinical characteristics. Timing-stratified associations and same-cohort model discrimination were also examined. Results AL occurred in 29 of 292 patients (9.9%). Patients with AL had a shorter QRS duration (median, 86 vs. 92 ms; P = 0.016) and a more leftward QRS axis (4 degrees vs. 27 degrees; P = 0.006). In the two-variable model, standardized odds ratios (ORs) were 0.378 (95% CI, 0.178-0.801) for QRS duration and 0.501 (0.323-0.779) for QRS axis. In the sensitivity model, the corresponding ORs were 0.359 (0.170-0.761) and 0.486 (0.299-0.789). The QRS-axis association was stronger preoperatively, whereas the QRS-duration association was stronger from day 0 through postoperative day 1. Median repeated-cross-validation AUCs were 0.702 for the ECG model, 0.559 for the clinical reference model, and 0.690 for the combined model; bootstrap confidence intervals for both AUC differences versus the clinical reference included zero. Conclusion Shorter QRS duration and a more leftward frontal-plane QRS axis were associated with AL after esophagectomy. These QRS measurements are potential perioperative signals that require prospective validation rather than established predictors.