Towards real-time cardiovascular magnetic resonance guided transarterial CoreValve implantation: in vivo evaluation in swine

<p>Abstract</p> <p>Background</p> <p>Real-time cardiovascular magnetic resonance (rtCMR) is considered attractive for guiding TAVI. Owing to an unlimited scan plane orientation and an unsurpassed soft-tissue contrast with simultaneous device visualization, rtCMR is presumed to allow safe device navigation and to offer optimal orientation for precise axial positioning. We sought to evaluate the preclinical feasibility of rtCMR-guided transarterial aortic valve implatation (TAVI) using the nitinol-based Medtronic CoreValve bioprosthesis.</p> <p>Methods</p> <p>rtCMR-guided transfemoral (n = 2) and transsubclavian (n = 6) TAVI was performed in 8 swine using the original CoreValve prosthesis and a modified, CMR-compatible delivery catheter without ferromagnetic components.</p> <p>Results</p> <p>rtCMR using TrueFISP sequences provided reliable imaging guidance during TAVI, which was successful in 6 swine. One transfemoral attempt failed due to unsuccessful aortic arch passage and one pericardial tamponade with subsequent death occurred as a result of ventricular perforation by the device tip due to an operating error, this complication being detected without delay by rtCMR. rtCMR allowed for a detailed, simultaneous visualization of the delivery system with the mounted stent-valve and the surrounding anatomy, resulting in improved visualization during navigation through the vasculature, passage of the aortic valve, and during placement and deployment of the stent-valve. Post-interventional success could be confirmed using ECG-triggered time-resolved cine-TrueFISP and flow-sensitive phase-contrast sequences. Intended valve position was confirmed by ex-vivo histology.</p> <p>Conclusions</p> <p>Our study shows that rtCMR-guided TAVI using the commercial CoreValve prosthesis in conjunction with a modified delivery system is feasible in swine, allowing improved procedural guidance including immediate detection of complications and direct functional assessment with reduction of radiation and omission of contrast media.</p

Endovascular repair of infrarenal aortic aneurysms in octogenarians and nonagenarians

ObjectiveThe purpose of this report was to present short and midterm results of endovascular aortic aneurysm repair (EVAR) of infrarenal aortic aneurysms in octogenarians and nonagenarians.MethodsBetween March 1994 and March 2011, elective EVAR was performed in 967 patients in our institution. This includes 279 patients older than 80 years at the time of the procedure (octogenarians: n = 252, nonagenarians: n = 27). Mean follow-up was 48.4 ± 34.5 months. A retrospective analysis was performed. Survival was calculated using Kaplan-Meier analysis and a survival comparison to patients who underwent EVAR <80 years old (n = 688) was performed. Cox hazard regression analysis was used to assess parameters that influence survival.ResultsTechnical success was 96% in octogenarians and 85% in nonagenarians. Technical failure in 15 of 279 patients includes primary type I endoleak (n = 6), procedure abortion due to inability to pass the iliac vessels (n = 6), and emergency conversion (n = 3). Thirty-day mortality was significantly higher for patients >80 years old (2.8% vs 1.0%; P = .044). Morbidity rates were 11.5% for octogenarians and 7.4% for nonagenarians with predominately cardiopulmonary complications. High-risk patients >80 years old showed a comparable perioperative mortality rate to low-/medium-risk patients >80 years old (2.9% vs 2.5%;P = .717), but a significantly higher complication rate (22.5% vs 9.2%; P = .0275) and reduced midterm survival with 1-, 3-, and 5-year survival rates of 79% ± SE 7%, 55% ± SE 8%, and 38% ± SE 9% (log-rank test P = .03). In high-risk patients age >80 years old, their age did not influence 30-day mortality (2.5% vs 2.7%; P = .978) and midterm survival. Survival in octogenarians at 1, 3, and 5 years was 87.9 ± SE 2.1%, 70.9 ± SE 3.0%, and 55.6% ± SE 3.5%, respectively. Survival in nonagenarians at 1 and 3 years was 96.3% ± SE 4% and 60.6% ± SE 10.4%. Higher cardiac (hazard ratio [HR], 1.22; P = .038) and renal risk scores (HR, 1.59; P = .0016), chronic obstructive pulmonary disease (HR, 1.56; P = .032), and anemia (HR, 2.1; P < .001) influenced midterm survival.ConclusionEVAR in octogenarians and nonagenarians is associated with a significantly higher but still low perioperative mortality compared to younger patients. Midterm survival in octogenarians and nonagenarians, although significantly lower than in younger patients, is still acceptable, indicating that age >80 years should not be an exclusion criteria for EVAR. Even high-risk patients >80 years can be treated safely with a low perioperative mortality and comparable midterm outcome to younger high-risk patients

Direct percutaneous sac injection for postoperative endoleak treatment after endovascular aortic aneurysm repair

BackgroundThis study presents the short-term and midterm results of direct percutaneous sac injection (DPSI) for postoperative endoleak treatment after endovascular aortic aneurysm repair (EVAR).MethodsBetween March 1994 and November 2011, EVAR was performed in 986 patients. The median follow-up was 63 ± 45 months (range, 0-211 months). A retrospective analysis was performed. DPSI was used in 21 patients for 19 type II endoleaks and two endoleaks of undefined origin (EOUO), of which 12 (57%) were after failure of a previous endovascular treatment attempt.ResultsDPSI using thrombin (n = 16), coils (n = 7), gelfoam (n = 6), or glue (n = 3), or a combination, was technically feasible in all patients. Saccography during DPSI revealed a previously undetected type I endoleak in three patients. Immediate DPSI success was achieved in 16 of 18 procedures (88.9%), with two complications. Glue incidentally intravasated in the inferior vena cava, causing a clinically nonsignificant subsegmental pulmonary artery embolism in one patient, and the temporary development of a type III endoleak, possibly from graft puncture, in another. During a median follow-up of 39 months (interquartile range, 13-88 months) after DPSI, recurrent endoleaks were observed in nine patients (50.0%), one type I endoleak due to graft migration, five type II endoleaks, and three EOUO. The occurrence of a re-endoleak during follow-up was significantly associated with dual-antiplatelet medication (0% in patients without re-endoleak vs 44.4% in patients with re-endoleak; P = .023) and with a nonsignificant trend for the use of aspirin alone (33.3% in patients without re-endoleak vs 80% in patients with re-endoleak; P = .094). Re-endoleak occurred in 33.3% of the patients without antiplatelet medication and in 100% of patients with dual-antiplatelet medication (P = .026). Thrombin was used as the sole embolic agent during the initial DPSI in all patients with dual-antiplatelet therapy. No other factor was significantly associated with re-endoleaks. Reintervention was deemed necessary in six patients within a median of 10 months (interquartile range, 4-16 months) after DPSI, including six additional DPSI treatments in four patients with type II re-endoleaks, cuff placements in one type I endoleak, and endograft relining in one EOUO.ConclusionsThis initial experience suggests that DPSI is feasible as a technique for endoleak treatment after EVAR. However, complications and endoleak recurrence remain a concern. The role of antiplatelet therapy and different embolic agents on long-term embolization success needs to be studied in more detail