Contemporary Outcomes after Treatment of Aberrant Subclavian Artery and Kommerell’s Diverticulum

Objective Aberrant Subclavian Artery (ASA) and Kommerell’s Diverticulum (KD) are rare vascular anomalies that may be associated with lifestyle-limiting and life-threatening complications. The aim of this study is to report contemporary outcomes after invasive treatment of ASA/KD using a large international dataset. Methods Patients who underwent treatment for ASA/KD (2000-2020) were identified through the Vascular Low Frequency Disease Consortium (VLFDC), a multi-institutional collaboration to investigate uncommon vascular disorders. We report early and mid-term clinical outcomes including stroke and mortality, technical success, and other operative outcomes including reintervention rates, patency and endoleak. Results Overall, 285 patients were identified during the study period. The mean patient age was 57; 47% were female and 68% presented with symptoms. A right-sided arch was present in 23%. Mean KD diameter was 47.4 mm (range 13-108). The most common indication for treatment was symptoms (59%), followed by aneurysm size (38%). The most common symptom reported was dysphagia (44%). A ruptured KD was treated in 4.2% of cases, with a mean diameter of 43.9 mm (range 18-100). An open procedure (Open) was performed in 101 cases (36%); the most common approach was ASA ligation with subclavian transposition. An endovascular or hybrid approach (Endo/Hybrid) was performed in 184 (64%); the most common approach was thoracic endograft and carotid-subclavian bypass. A staged operative strategy was employed more often than single setting repair (55% vs. 45%). Compared to Endo/Hybrid, those in the Open group were more likely to be younger (49 vs. 61 years; p < .0001), female (64% vs. 36%; p < .0001) and symptomatic (85% vs. 59%; p < .0001). Complete/partial symptomatic relief at 1 year after intervention was 82.6%. There was no association between modality of treatment and symptom relief (open 87.2% vs. endo/hybrid 78.9%; p=0.13). Post-intervention, 11 (4.5%) subclavian occlusions occurred; 3 were successfully thrombectomized resulting in a primary and secondary patency of 95% and 96% respectively, at a median follow-up of 39 months. Among the 33 (12%) reinterventions, the majority were performed for endoleak (36%), and more reinterventions occurred in the Endo/Hybrid than Open group (15% vs. 6%; p = .02). Overall survival was 87.3% at a median follow-up of 41 months. The 30-day stroke and death rates were 4.2% and 4.9%, respectively. Urgent/emergent presentation was independently associated with increased risk of 30-day mortality (OR 19.8, 95% CI 3.3-116.6), overall mortality (OR 3.6, 95% CI 1.2-11.2) and intraoperative complications (OR 8.3, 95% CI 2.8-25.1). Females had higher risk of reintervention (OR 2.6, 95% CI 1-6.5). At an aneurysm size of 44.4 mm, Receiver Operator Characteristic (ROC) curve analysis suggested that 60% of patients would have symptoms. Conclusions Treatment of ASA/KD can be performed safely with low rates of mortality, stroke and reintervention, and high rates of symptomatic relief regardless of repair strategy. Symptomatic and urgent operations were associated with worse outcomes in general, and female gender was associated with a higher likelihood of reintervention. Given the worse overall outcomes when symptomatic and the inherent risk of rupture, consideration of repair at 40 mm is reasonable in most patients. ASA/KD can be repaired in asymptomatic patients with excellent outcomes and young healthy patients may be considered better candidates for open approaches versus endovascular/hybrid modalities, given the lower likelihood of reintervention and lower early mortality rate.