Thorakale Aorten-Stentgraftimplantation

Management of Systemic Inflammatory Response Syndrome After Cardiovascular Interventions. Diagnostic, Prognostic, and Therapeutic Implications

A substantial number of patients may experience systemic inflammatory response syndrome (SIRS) and related adverse events after transcatheter aortic valve implantation and endovascular aortic aneurysm repair. Although a clear etiology has not been established, endothelial disruption and tissue-ischemic response secondary to the foreign material may represent the trigger events. A latency period (0 to 48 hours) may occur between the initial injury and onset of symptoms mirroring an initial local response followed by a systemic response. Clinical presentation can be mild or severe depending on external triggers and characteristics of the patient. Diagnosis is challenging because it simulates an infection, but lack of response to antibiotics, negative cultures are supportive of SIRS. Increased in-hospital stay, readmissions, major cardiovascular events, and reduced durability of the device used are the main complications. Treatment includes non-steroidal anti-inflammatory drugs or corticosteroids. In conclusion, further studies are warranted to fully explore pathophysiologic mechanisms underpinning SIRS and the possibility of enhancing device material immune compatibility to reduce the inflammatory reaction of the host tissue.

Real-time vascular interventional magnetic resonance imaging

Endovascular stent-graft placement is emerging as a promising alternative to medical and surgical treatment of patients with diseases of the descending thoracic and abdominal aorta. Precise placement of the stentgraft, which is currently performed under x-ray control, remains, however, challenging as there are several shortcomings to fluoroscopic guidance beyond that related to the harmful effect of radiation exposure and nephrotoxic contrast media. While transesophageal echocardiography and intravascular ultrasound have been used as adjunct imaging modalities during endovascular stent-graft procedures to overcome the limitations of angiography, these techniques have not mitigated the need for fluoroscopy. Magnetic resonance imaging (MRI) guidance of vascular interventional procedures offers several potential advantages over fluoroscopy-guided techniques, including image acquisition in any desired orientation, superior 3D soft-tissue contrast with simultaneous visualization of the interventional device, absence of ionizing radiation, and avoidance of nephrotoxic contrast media. Magnetic resonance imaging is often used for pre-operative diagnosis of aortic disease and can provide all relevant information for the planning of endovascular stent-graft procedures as well as for accurate and immediate post-interventional evaluation. However, visualization of interventional instruments by MRI has proven to be the chief obstacle. This article will review current approaches that have been developed for depicting vascular instruments by MRI and will also discuss the first experimental experiences with MRI-guided endovascular stent-graft placement in a swine model of aortic dissection.