Chronic and Acute-on-Chronic mesenteric ischemia as different entities: outcomes of 25-year-period study

Introduction Chronic mesenteric ischemia (CMI) and acute-on-chronic mesenteric ischemia (AoCMI) have gained increasing relevance in recent years, primarily due to the aging population and the global spread of atherosclerosis. While CMI presents as a chronic condition, typically symptomatic in cases of multivessel involvement and characterized by angina abdominis, AoCMI reflects an acute exacerbation of a preexisting chronicity. The aim of the present study was to evaluate mid-term follow-up outcomes in patients with CMI vs. AoCMI. The primary outcome was overall and disease-specific mortality. Secondary outcomes included estimated reintervention rates during follow-up and identification of predictors for reintervention in both groups. Materials and Methods A total of 68 patients treated for either CMI or AoCMI at our center between 2000 and 2025 were retrospectively analyzed. A notable female predominance was observed, particularly in the CMI group. Among the 68 patients included, 26 were male (38.2%) and 42 female (61.8%); in the CMI group specifically, the number of females was approximately double that of males (63.8% vs. 36.2%). Collected data included clinical history (e.g., smoking status, ongoing therapy prior to the event, comorbidities such as diabetes, coronary artery disease, peripheral artery disease, hypertension, dyslipidemia, COPD, chronic kidney disease, cancer, obesity, and atrial fibrillation), as well as imaging details of the treated vessel, stenosis characteristics, and procedural urgency. Results Our findings indicated that perioperative mortality—defined as death occurring within 30 days of the intervention or during the same hospital stay, even if beyond 30 days—was significantly higher in the AoCMI group compared to CMI (19.1% vs. 4.3%). Likewise, overall mortality was greater among AoCMI patients (42.8% vs. 38.3%), as well as disease-related mortality with 23.8% for AoCMI and 10.6% for CMI. Regarding reintervention rates, both groups showed approximately 13% incidence within the first year, corresponding to a freedom from reintervention of 87.1% in the CMI group (95% CI: 68.9%–94.9%) and of 87.3% in AoCMI group (95% CI: 38.7% - 98.1%). Over time, however, CMI patients exhibited a higher cumulative risk, reaching 35.1% at five years vs. 27.1% in AoCMI, with freedom from reintervention at five years of 64.9% in the CMI group (95% CI: 39.1%–81.9%) and 72.9% in the AoCMI group (95% CI: 27.6%–92.5%). To identify predictors of reintervention, a multivariate Cox regression analysis was performed. Results showed that the presence of calcified stenosis was significantly associated with a reduced risk of reintervention (HR=0.1; 95% CI: 0.02-0.6; P=0.012). In contrast, smoking habit tripled the likelihood of requiring a second procedure (HR=3.0; 95% CI: 1.2-6.9; P=0.012), and primary treatment with PTA alone was associated with a ninefold increased risk (HR=9.2; 95% CI: 2.0-43.2; P=0.005). Conclusions The relatively higher perioperative mortality observed in the AoCMI group aligns with the underlying pathophysiological mechanisms. In CMI patients—typically affected by multivessel disease—the acute occlusion of a single vessel may impair compensatory mechanisms, leading to patient death. As for overall and disease-related mortality, these outcomes may be biased by the limited sample size. Although reintervention rates were similar at one year, they were higher at five years in the CMI group, likely reflecting their longer survival. Regarding reintervention predictors, the association of smoking and initial PTA-only treatment with increased risk is consistent with current literature. Conversely, the identification of calcified lesions as a protective factor diverges from current evidence and warrants further investigation.