Alexandros Kafetzakis

Vascular Endostapling: New Concept for Endovascular Fixation of Aortic Stent-Grafts

Purpose: To evaluate the feasibility of a new vascular endostapling system in treating infrarenal abdominal aortic aneurysms using commercially available endografts. Methods: Eight patients (6 men; mean age 71 years, range 59–82) underwent endovascular aneurysm repair (EVAR) using Talent or Zenith stent-grafts and the Anson Refix clip, which provides transmural aortic fixation of the endoprosthesis with high pullout force proportional to the number of the clips deployed. Results: Twenty (69%) of the 29 endostaples were successfully implanted and secured with the endostaple system; 9 clips that did not fully penetrate the graft and tissue due to severe calcification of the neck were retracted successfully into the delivery device. The delivery time from insertion of the Refix delivery catheter to its withdrawal was a mean 57 minutes (range 20–102) over and above the regular stent-graft procedure. Notably, the delivery time was reduced as the learning curve was passed: mean 89.75 minutes in the first 4 cases versus 27.5 minutes in the last 4. No endostaple migrated or was lost from the intended deployment site based on radiological imaging. No patients had evidence of perioperative endoleak based on computed tomography. No endograft-related complications have been documented during follow-up at 30 days. Conclusion: The initial experience established the safety and feasibility of EVAR using the Anson Refix endostapling system. However, further clinical evaluation is mandatory to draw robust conclusions about the utility of this new concept for fixation of aortic stent-grafts.

Acute lower limb ischemia as the initial symptom of acute myeloid leukemia

Although coagulatory system disorders are well recognized in patients with acute leukemia, these usually present with either hemorrhagic complications or thrombosis of small vessels. Large vessel thrombosis is a very rare clinical presentation. We present a patient with previously undiagnosed acute myeloid leukemia (M5), who was referred to our hospital with symptoms of acute ischemia of his right lower limb. Occlusion of the right external iliac artery due to a combination of leucostasis and coagulation disorders was noted and successfully treated with urgent leukapheresis, immediate chemotherapy and surgical thromboembolectomy.

Graft inflow stenosis induced by the inflatable ring fixation mechanism of the Ovation stent-graft system: hemodynamic and clinical implications.

Purpose: To investigate the observed inflow stenosis at the O-rings of the Ovation stent-graft and evaluate its hemodynamic and clinical impact. Methods: The study involved 49 consecutive patients (48 men; mean age 71.2±7.7 years) treated successfully with the Ovation abdominal aortic stent-graft between June 2011 and January 2014 at a single center. Cross-sectional area and radius measurements of the infrarenal aorta just proximal to the sealing mechanism, as well at the site of stenosis, were measured from 3D reconstructions of the 1-month postoperative computed tomographic angiograms. Based on Poiseuilles law, the predicted pressure drop was calculated for each patient based on the length of the stenosis. Invasive blood pressure measurements at 3 levels (proximal to the inflatable rings, halfway inside the stenosis, and distal to the stenosis) were obtained in 10 patients intraoperatively. Ankle-brachial index (ABI) values preoperatively were compared to those after the procedure for all patients to assess the clinical impact of this phenomenon. Results: Median internal cross-sectional area at the site of the stenosis was significantly reduced compared to the area just proximal to the O-rings [57% reduction: 123 mm2 (range 28–254) vs. 283 mm2 (range 177–531), respectively; p<0.001]. The same was observed for the radius [6.5 mm (range 3–9) vs. 9.5 mm (range 7.5–13), respectively; p<0.001]. Based on the median 15 mm length of the stenosis (range 13–17) observed in the study population, a median pressure drop of 0.13 mmHg (range 0–0.25) along the stenosis was calculated. Invasive blood pressure measurements indicated a non-significant pressure change along the stenosis (e.g., 0.7 mmHg between the proximal level and halfway inside the stenosis). ABI remained practically unchanged postoperatively. Conclusion: The advantages of the Ovation devices unique sealing mechanism come at the expense of a median area inflow stenosis of ∼60%. This stenosis does not cause a hemodynamically significant pressure drop. Future modification of the graft ring design may be needed in order to reduce this stenosis.

Effectiveness of Platelet-Rich Plasma to Enhance Healing of Diabetic Foot Ulcers in Patients With Concomitant Peripheral Arterial Disease and Critical Limb Ischemia

We sought to investigate the effect of autologous platelet-rich plasma (PRP) on the healing rate of diabetic foot ulcers in patients with diabetes and concomitant peripheral arterial disease (PAD). Diabetic patients with foot ulceration presenting with PAD who were treated with local growth factors in a single center, during a 24-month period from May 2009 to April 2011, were retrospectively reviewed. Based on the severity of PAD, subjects were divided into groups A (Fontaine classification stages I, IIa, and IIb) and B (Fontaine classification stages III and IV), with those included in the latter being considered to suffer from critical limb ischemia (CLI). End points of the analysis were clinical improvement, limb salvage, and amputation rate. Outcome was compared between groups A and B. Overall, 72 patients were evaluated, 30 with CLI. Ulcer area reduction >50% was observed in 58/72 patients while reduction >90% was achieved in 52/72 patients. There were 14 (19%) major and minor amputations, whereas the limb salvage rate was 89%. This variable was significantly different between groups A and B (100% vs 73%, P < .001), as is rate of reduction in ulcer area >90% (83% vs 56%, P = .02). Reduction of ulcer area >50% was observed in the majority of patients in both groups (group A 86% vs group B 73%, P = .23). In conclusion, PRP could serve as a useful adjunct during management of diabetic foot ulcers even in diabetic patients with unreconstructable arterial disease.

Spontaneous Type Ia Endoleak Sealing in Patients Undergoing Endovascular Aneurysm Repair With the Ovation Stent Graft

BACKGROUND Type Ia endoleak may lead to continuous sac pressurization and late rupture after endovascular aneurysm repair (EVAR). Nevertheless, there have been scarce reports suggesting that these endoleaks may occasionally present spontaneous sealing. Taking into account the original sealing mechanism of the Ovation endograft that exploits 2 polymer-filled O-rings, we hypothesize that spontaneous type Ia endoleak sealing may sometimes incur following implantation of this device. We aim to report our experience with spontaneous type Ia endoleak sealing in patients treated with the Ovation endograft. METHODS This is a retrospective observational study which included all patients undergoing EVAR with the Ovation endograft in a single institution during a 6-year period. Patients with an intraoperative type Ia endoleak were identified. The primary endpoint was rate of spontaneous sealing. Secondary endpoints were migration, sac expansion, need for reinterventions, secondary type Ia endoleaks, and aneurysm-related and overall mortality. Adherence to the instructions for use (IFU) was evaluated to examine relation with occurrence of endoleak and rates of spontaneous sealing. RESULTS Among 147 patients treated, 8 (5%) left the operation theater with a type Ia endoleak. In 6 patients, the endoleak spontaneously resolved during a maximum of 3 months of follow-up. Among those, 5 cases were treated outside the IFU (2 short necks and 3 with severe angulation), while the sixth was a patient treated inside the IFU but was anticoagulated. In 2 patients, the endoleak did not spontaneously resolve. One presented a conical neck of marginal length and the other circumferential calcifications. Type Ia endoleak was significantly more common among patients treated in an off-label fashion. CONCLUSIONS Spontaneous sealing of type Ia endoleak is common after EVAR with the Ovation endograft. Nonadherence to the IFU results in more endoleaks, but it does not seem to reduce possibilities for spontaneous sealing.

Medical management of acute type a aortic dissection in association with early open repair of acute limb ischemia may prevent aortic surgery.

Summary Background: Acute type A aortic dissection (AAAD) is a cardiovascular emergency with a high potential for death. Rapid surgical treatment is indicated to prevent fatal complications. Aggressive appropriate medical management starts at first suspicion and is essential to prevent exacerbation or rupture of the dissection. Despite improved surgical techniques, perioperative care and the development of specialized cardiovascular centers, mortality remains high. Organ ischemia is a catastrophic manifestation of aortic dissection, demanding acute surgical intervention in specialized cardiovascular centers. Case Report: We present the case of a 62-year-old man with isolated acute limb ischemia due to an acute type A aortic dissection treated in a regional general hospital, without a specialized cardiovascular service, with immediate open malperfusion repair and aggressive medical management. The patient did not undergo further surgical aortic repair, and after a 30-month follow-up he remains symptom free and in good clinical condition, suggesting that although aortic surgery remains the gold standard for treatment of acute Type A dissection, appropriate medical management and early malperfusion repair may offer an initial limb- or life-saving procedure. Conclusions: This staged approach gives clinicians more time to properly evaluate and transfer the patient to a specialized cardiovascular center, and in some cases may even offer a definite treatment.

A delayed diagnosis that altered the professional orientation of an athlete with upper limb chronic arterial embolization

Summary Background Vascular disorders of the upper extremity in young and physically active patients present a complex and challenging problem for the treating physician. Initial presentation may often be subtle and the consequences of misdiagnosis, delayed diagnosis or mistreatment can be severe. Case Report In this report, we discuss a case of a young woman with chronic upper limb ischemia due to an arterial thoracic outlet syndrome in whom even though symptoms persisted over a number of years during which she frequently sought medical consultation, remained undiagnosed until finally presenting with limb-threatening ischemia. Furthermore, due to this delay, the patient was forced to withdraw from her professional carrier in athletics. Conclusions A thoughtful and through approach combining the history, physical findings, and use of appropriate diagnostic aids will provide the physician and patient with the greatest opportunity for a satisfactory outcome. Furthermore, a delay in definitive treatment may not only cause health deterioration, but may also incur social, economic and occupational consequences.