The impact of intervention timing, etiology, and revascularization strategy on acute mesenteric ischemia outcomes

Acute mesenteric ischemia (AMI) is a highly lethal presentation associated with significant perioperative morbidity. Unlike other acute cardiovascular emergencies, outcomes of AMI have shown minimal improvement over time. Among the strategies explored to decrease AMI-related mortality, early diagnosis and prompt surgical revascularization remain most critical for improving both short- and long-term AMI outcomes. This study aims to investigate the impact of time from acute symptom onset to operative intervention on AMI outcomes.

All patients who underwent revascularization for AMI between January 2014 and December 2024 at our quaternary medical center were identified. AMI was defined as mesenteric ischemia with acute symptom onset of ≤2 weeks duration. Patients with AMI secondary to mechanical bowel obstruction, trauma, aortic dissection, mesenteric venous thrombosis, or nonocclusive mesenteric ischemia were excluded. Patients were then categorized and compared based on the time interval from acute symptom onset to revascularization, etiology of AMI, and revascularization strategy. Kaplan-Meier and Cox regression analyses were used to estimate long-term event rates and evaluate the independent association between exposure variables and long-term outcomes or survival, AMI recurrence, and reintervention.

There were 92 patients who met the inclusion criteria. An inflection point at 48 hours was identified (sensitivity 81%, specificity 63%), where patients treated >48 hours after symptom onset had significantly higher rates of perioperative mortality (39% vs 14%; P = .012) and short bowel syndrome (39% vs 12%; P = .002) compared with patients treated within 48 hours of symptom onset. Revascularization >48 hours after acute symptom onset was also associated with higher long-term mortality (hazard ratio [HR], 2.95; 95% confidence interval [CI], 1.43-6.07; P = .003), AMI recurrence (HR, 6.36; 95% CI, 1.59-25.38; P = .009), and reintervention (HR, 3.89; 95% CI, 1.22-12.36; P = .021) compared with revascularization within 48 hours. AMI secondary to acute thrombosis was associated with an increased risk of AMI recurrence (HR, 5.97; 95% CI, 1.05-25.38; P = .048) and reintervention (HR, 8.02; 95% CI, 1.04-61.95; P = .046) compared with embolic AMI, with no difference observed in long-term mortality (HR, 0.79; 95% CI, 0.34-1.82; P = .577). No difference was observed between open and endovascular/retrograde open mesenteric stenting revascularization in long-term mortality (P = .344), AMI recurrence (P = .268), and reintervention (P = .685). Significant predictors of perioperative mortality were age (P = .049), time from acute symptom onset to revascularization >48 hours (P = .021), and lactate level at presentation (P = .029).

Optimal outcomes after AMI can be achieved with timely diagnosis and revascularization. In our experience, diagnosis and intervention within 48 hours decreased mortality, recurrence, reintervention, bowel resection, and short bowel syndrome, and enhanced overall patient outcomes. AMI etiology and management strategy did not affect short-term outcomes, although acute thrombosis was associated with an increased risk of AMI recurrence and reintervention compared with embolic AMI, with no difference in long-term mortality.