Figure 3 - uploaded by Prof Sherif Sultan
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-Plots demonstrating individual Kaplan Meier for each Crawford classification of TAAA. A) Extent I; B) extent II; C) extent III; D) extent IV; E) extent V.
Source publication
BACKGROUND: We report early outcomes of patients with thoracoabdominal aortic aneurysm (TAAA) and chronic symptomatic aortic dissection (CSAD) managed by the streamliner multilayer flow modulator (SMFM).
METHODS: Out of 876 SMFM implanted globally, we have knowledge of 542. To date, 384 patients maintained in the MFM global registry, of which 151 w...
Context in source publication
Similar publications
BACKGROUND: Data from the International Registry of Acute Aortic Dissection indicate that the guideline criterion of 5.5 cm for ascending aortic intervention misses many dissections occurring at smaller dimensions. Furthermore, studies of natural behavior have generally treated the aortic root and the ascending aorta as 1 unit despite embryological...
Citations
... The current framework readily allows for simulation of the effects of endovacular aortic repair or stenting on left ventricular performance. This is particulary relevant clinically, with recent studies uncovering a link between proximal aortic stenting and left ventricular hypertophy [73], [74] and cardiac deaths [75]. Moreover animal studies have shown that placing a graft in the native porcine aorta diminishes the windkessel effect [76], as evident in this model when the high-compliance regime is removed. ...
... In the final report from the MFM Global Registry, 13 the investigators compared flow modulation technology in the management of complex thoracoabdominal aortic aneurysm (TAAA) to its use in chronic symptomatic AD. Interestingly, the authors discovered that the MFM was associated with increased cardiac events, which was further elevated when the devices were implanted nearer to the heart and the stents covered a longer aortic length. ...
... The MFM is not a resolution for patients living on borrowed time and must not be used erratically in those patients in whom other modus operandi of aortic repair are not achievable. [10][11][12][13][14] Costache et al 1 mirrored the findings of the MFM Global Registry that aortic aneurysms are chronic end-stage diseases in which the MFM cannot induce aortic remodeling once the TAAA diameter exceeds 6.2 cm. However, it does lower the aortic wall stress pressure, and that is why the MFM is suitable only for managing AD. ...
Background
Thoracoabdominal acute aortic syndrome is associated with high morbidity and mortality. We aim to scrutinize our evolving strategies for acute aortic syndrome (AAS) management using minimally invasive and adaptive surgical techniques over two decades.
Methods
This is a longitudinal observational study at our tertiary vascular centre from 2002 to 2021. Out of 22,349 aortic referrals, we performed 1,555 aortic interventions over twenty years. Amongst 96 presented with symptomatic aortic thoracic pathology, 71 patients had AAS. Our primary endpoint is combined aneurysm-related and cardiovascular-related mortality.
Results
There were 43 males and 28 females (5 Traumatic Aortic Transection (TAT), 8 Acute Aortic Intramural Hematoma (IMH), 27 Symptomatic Aortic Dissection (SAD) and 31 Thoracic Aortic Aneurysm (TAA) post-SAD) with a mean age of 69. All the patients with AAS received optimal medical therapy (OMT), but TAT patients underwent emergency thoracic endovascular aortic repair (TEVAR). Fifty-eight patients had an aortic dissection, of which 31 developed TAA. These 31 patients with SAD and TAA received OMT initially and interval surgical intervention with TEVAR or sTaged hybrId sinGle lumEn Reconstruction (TIGER). To increase our landing area, we performed a left subclavian chimney graft with TEVAR in twelve patients. The average follow-up duration was 78.2 months, and eleven patients (15.5%) had combined aneurysm and cardiovascular-related mortality. Twenty-six percentage of the patients developed endoleaks (EL), of which 15% required re-intervention for type II and III. Four patients who had paraplegia (5.7%) and developed renal failure died. None of our patients had a stroke or bowel ischaemia. Twenty patients had OMT, eight of these were patients with acute aortic hematoma, and all eight died within 30 days of presentation.
Conclusion
Acute aortic hematoma is a sinister finding, which must be closely monitored, and consideration is given to early intervention. Paraplegia and renal failure result in an increased mortality rate. TIGER technique with interval TEVAR has salvaged complex situations in young patients. Left subclavian chimney increases our landing area and abolishes SINE. Our experience shows that minimally invasive techniques could be a viable option for AAS.
The effect of repair techniques on the biomechanics of the aorta is poorly understood, resulting in significant levels of postoperative complications for patients worldwide. This study presents a computational analysis of the influence of Nitinol-based devices on the biomechanical performance of a healthy patient-specific human aorta. Simulations reveal that Nitinol stent-grafts stretch the artery wall so that collagen is stretched to a straightened high-stiffness configuration. The high-compliance regime (HCR) associated with low diastolic lumen pressure is eliminated, and the artery operates in a low-compliance regime (LCR) throughout the entire cardiac cycle. The slope of the lumen pressure–area curve for the LCR post-implantation is almost identical to that of the native vessel during systole. This negligible change from the native LCR slope occurs because the stent-graft increases its diameter from the crimped configuration during deployment so that it reaches a low-stiffness unloading plateau. The effective radial stiffness of the implant along this unloading plateau is negligible compared to the stiffness of the artery wall. Provided the Nitinol device unloads sufficiently during deployment to the unloading plateau, the degree of oversizing has a negligible effect on the pressure–area response of the vessel, as each device exerts approximately the same radial force, the slope of which is negligible compared to the LCR slope of the native artery. We show that 10% oversizing based on the observed diastolic diameter in the mid descending thoracic aorta results in a complete loss of contact between the device and the wall during systole, which could lead to an endoleak and stent migration. 20% oversizing reaches the Dacron enforced area limit (DEAL) during the pulse pressure and results in an effective zero-compliance in the later portion of systole.
