Giovanni Rossi

Objective: To evaluate early and mid-term outcomes of thoracic endovascular aortic repair (TEVAR) using the Castor single-branched aortic stent graft in a real-world multicenter Italian experience. Methods: This retrospective, nonrandomized, multicenter study included all consecutive patients treated with the Castor stent graft between January 2019 and April 2025 in eight Italian centers. The device was used in patients with thoracic aortic pathologies requiring TEVAR in proximal landing zones 1 or 2. Primary endpoints included technical success, intraoperative major adverse events (MAEs), and deployment accuracy. Secondary endpoints were aortic-related mortality, neurological complications, reinterventions, and endoleaks. Results: Fifty-one patients (mean age 68.8 ± 8 years, 75.5% male) were treated, primarily for type B aortic dissection (45.1%) and thoracic aortic aneurysm (27.5%). Proximal landing was in zone 2 in 92.1% and zone 1 in 7.8% of cases. The technical success rate was 94.1%, with three cases (5.8%) of intraoperative type Ia endoleak. No intraoperative deaths or major adverse events occurred. Two cases of minor embolic stroke (3.9%) were observed, both in zone 1 procedures involving left common carotid artery revascularization. At a median follow-up of 22.3 months (range 2–58), no additional endoleaks or neurological events were reported, with 100% branch patency rate. Conclusions: The Castor single-branched stent graft is a feasible option for TEVAR in zone 2, with high technical success and low rates of neurological complications. Accurate case selection and procedural planning are essential.

Background/Objectives: The aberrant subclavian artery (ASA) represents the most common congenital anomaly of the aortic arch, and is frequently associated with a Kommerell diverticulum, an aneurysmal dilation at the anomalous vessel origin. This condition carries a significant risk of rupture and dissection, and growing evidence indicates that local hemodynamic alterations may contribute to its development and progression. Computational Fluid Dynamics (CFD) provides a valuable non-invasive modality to assess biomechanical stresses and elucidate the pathophysiological mechanisms underlying these vascular abnormalities. Methods: In this study, twelve thoracic CT angiography scans were analyzed: six from patients with ASA and six from individuals with normal aortic anatomy. CFD simulations were performed using OpenFOAM, with standardized boundary conditions applied across all cases to isolate the influence of anatomical differences in flow behavior. Four key hemodynamic metrics were evaluated—Wall Shear Stress (WSS), Oscillatory Shear Index (OSI), Drag Forces (DF), and Turbulent Viscosity Ratio (TVR). The aortic arch was subdivided into Ishimaru zones 0–3, with an adapted definition accounting for ASA anatomy. For each region, time- and space-averaged quantities were computed to characterize mean values and oscillatory behavior. Conclusions: The findings demonstrate that patients with ASA exhibit markedly altered hemodynamics in zones 1–3 compared to controls, with consistently elevated WSS, OSI, DF, and TVR. The most pronounced abnormalities occurred in zones 2–3 near the origin of the aberrant vessel, where disturbed flow patterns and off-axis mechanical forces were observed. These features may promote chronic wall stress, endothelial dysfunction, and localized aneurysmal degeneration. Notably, two patients (M1 and M6) displayed particularly elevated drag forces and TVR in the distal arch, correlating with the presence of a distal aneurysm and right-sided arch configuration, respectively. Overall, this work supports the hypothesis that aberrant hemodynamics contribute to Kommerell diverticulum formation and progression, and highlights the CFD’s feasibility for clarifying disease mechanisms, characterizing flow patterns, and informing endovascular planning by identifying hemodynamically favorable landing zones.

A patient with prior ascending aortic replacement for a type A acute dissection and a bovine arch presented with an asymptomatic chronic dissecting innominate artery aneurysm extending to both carotid arteries. As the patient refused redo open surgery, we performed a hybrid procedure with reverse extra-anatomic aortic arch debranching and a fenestrated endograft. The aneurysm was still partially perfused due to an endoleak and corrected 1 week later with vascular plugs.