Predicting risk of rupture and rupture-preventing reinterventions following endovascular abdominal aortic aneurysm repair.

BACKGROUND: Clinical and imaging surveillance practices following endovascular aneurysm repair (EVAR) for intact abdominal aortic aneurysm (AAA) vary considerably and compliance with recommended lifelong surveillance is poor. The aim of this study was to develop a dynamic prognostic model to enable stratification of patients at risk of future secondary aortic rupture or the need for intervention to prevent rupture (rupture-preventing reintervention) to enable the development of personalized surveillance intervals. METHODS: Baseline data and repeat measurements of postoperative aneurysm sac diameter from the EVAR-1 and EVAR-2 trials were used to develop the model, with external validation in a cohort from a single-centre vascular database. Longitudinal mixed-effects models were fitted to trajectories of sac diameter, and model-predicted sac diameter and rate of growth were used in prognostic Cox proportional hazards models. RESULTS: Some 785 patients from the EVAR trials were included, of whom 155 (19·7 per cent) experienced at least one rupture or required a rupture-preventing reintervention during follow-up. An increased risk was associated with preoperative AAA size, rate of sac growth and the number of previously detected complications. A prognostic model using predicted sac growth alone had good discrimination at 2 years (C-index 0·68), 3 years (C-index 0·72) and 5 years (C-index 0·75) after operation and had excellent external validation (C-index 0·76-0·79). More than 5 years after operation, growth rates above 1 mm/year had a sensitivity of over 80 per cent and specificity over 50 per cent in identifying events occurring within 2 years. CONCLUSION: Secondary sac growth is an important predictor of rupture or rupture-preventing reintervention to enable the development of personalized surveillance intervals. A dynamic prognostic model has the potential to tailor surveillance by identifying a large proportion of patients who may require less intensive follow-up.

Staged procedures for prevention of spinal cord ischemia in endovascular aortic surgery.

BACKGROUND: Spinal cord ischemia with development of paraplegia is the most relevant complication of thoracoabdominal aortic surgery caused by compromising the segmental arteries. To prevent this devastating complication in endovascular aortic surgery, staging procedures have been developed to reinforce collateral blood flood to the spinal cord. RESULTS: In patients with a medium to high risk for spinal cord ischemia, staged aortic repair is recommended. The classical staged repair is the two-step repair with delayed implantation of the aortic stent grafts. Additionally, more recent methods for short-term salvage of segmental artery perfusion by leaving an endoleak have been developed. Perfusion branches, delayed bridging stents as well as the open branch technique are among these methods. The latest option of staged repair is minimally invasive segmental artery embolization. CONCLUSION: Besides the nonsurgical options for monitoring and therapy of spinal cord ischemia, various staging procedures are available, which can be implemented depending on the patient and the aortic anatomy. Evidence that underlines staged repair for endovascular treatment of thoracoabdominal aortic pathologies is mostly based on retrospective studies.

Radiation Dosage for Percutaneous PAD Treatment is Different in Cardiovascular Disciplines: Results From an Eleven Year Population Based Registry in the Metropolitan Area of Hamburg.

OBJECTIVE: The worldwide prevalence of peripheral artery disease (PAD) has evolved to an intervention as the primary treatment option and therefore radiation is used with escalating incidence. Dose area product (DAP) correlates well with the total energy imparted to the patient during fluoroscopic interventions. This study aims to determine whether there are any associations among stage of disease, gender, age, and expertise on the radiation dose in single endovascular treatments of PAD. METHODS: This study was a prospective, mandatory, population based cross-sectional registry design. In total, 24,000 invasive percutaneous endovascular treatments of PAD conducted in the metropolitan area of Hamburg (Germany) were consecutively collected between January 2004 and December 2015. DAP was analysed by discipline conducting the procedure, Fontaine classification, patient gender, and age. RESULTS: Statistically significant differences in median DAP values were found. The lowest median DAP values were observed in surgical centres (7.1 vs. 18.0 Gy*cm2, p<.001) and in endovascular revascularisations (ER) following multidisciplinary consultation (11.6 vs. 23.4 Gy*cm2, p<.001). Considering the treatment of intermittent claudication, men had statistically significantly higher DAP values compared with women. Furthermore, lower median DAP values were observed in higher age groups, with lowest dosages in octogenarians. CONCLUSION: This is the first large population based study on DAP during ER for PAD. Several significant differences in median DAP values were observed, although patient stratification was comparable. Pre-operative therapy strategy planning can lead to lower DAP values, emphasising the importance of further vascular research and quality improvement projects targeting this topic. To date, available evidence is limited and therefore there is no accepted range of DAP levels. However, the ever increasing use of fluoroscopic interventions means that further investigation into radiation exposure to patients and healthcare professionals is required in order to keep DAP levels low.

Chronic type B aortic dissection: indications and strategies for treatment.

Chronic type B aortic dissection is a distinctive condition that needs individual treatment strategies and different considerations than in therapy of acute or subacute type B aortic dissection. The most common indication for treatment of this complex disease is aneurysmal dilatation of the dissected aortic segment. While open repair of the enlarged dissected aorta remains the best option for good-risk patients and patients with connective tissue disorders in high-volume centers with respective expertise, endovascular management of chronic type B aortic dissection with postdissection aneurysms has significantly gained ground in the past years. But the concept of TEVAR with implantation of a tubular stent-graft into the thoracic aorta to seal the proximal entry tear and reroute the blood flow into the true lumen alone, is not associated with satisfactory results. This is mainly due to the sparse remodeling capacity of the aortic tissue compared to earlier stages of the disease as the aortic wall and the dissection membrane are thickened and more rigid. On the other hand, it is restricted by the most limiting factor for endovascular success in chronic type B aortic dissection: persistent false lumen perfusion. This problem also affects patients with residual dissection after surgical repair of a DeBakey type I aortic dissection or dissection after ascending aortic repair for other pathologies. Hence, it is evident that strategies to achieve endovascular false lumen occlusion are of increasing importance and novel techniques have been introduced to solve the problem of persisting false lumen flow. Thus, the evolution of a large variety of techniques to address the false lumen perfusion issue indicates that complicated chronic type B dissection involves a high diversity in clinical presentation and morphology. A large armamentarium of catheter skills as well as critical individualized treatment strategies are required to address the heterogenous morphological disease pattern for each individual patient. The rapid development in endovascular techniques gives new directions for treatment indications and strategies in chronic aortic dissection and enables new insights into this old disease.