Comparison of a New bioprosthetic Mitral Valve to Other Commercially Available Devices Under Controlled Conditions in a Porcine Mode

BACKGROUND/AIM: To evaluate three mitral bioprostheses (of comparable measured internal diameters) under controlled, stable, hemodynamic and surgical conditions by bench, echocardiographic, computerized tomography and autopsy comparisons pre‐ and postvalve implantation. METHODS: Fifteen similar‐sized Yorkshire pigs underwent preprocedural computerized tomography anatomic screening. Of these, 12 had consistent anatomic features and underwent implantation of a mitral bioprosthesis via thoracotomy on cardiopulmonary bypass (CPB). Four valves from each of three manufacturers were implanted in randomized fashion: 27‐mm Epic, 27‐mm Mosaic, and 25‐mm Mitris bioprostheses. After CPB, epicardial echocardiographic studies were performed to assess hemodynamic function and define any paravalvular leaks, followed by postoperative gated contrast computerized tomography. After euthanasia, animals underwent necropsy for anatomic evaluation. RESULTS: All 12 animals had successful valve implantation with no study deaths. Postoperative echocardiographic trans‐valve gradients varied among bioprosthesis manufacturers. The 25‐mm Mitris (5.1 ± 2.7)/(2.6 ± 1.3 torr) had the lowest peak/mean gradient and the 27‐mm Epic bioprosthesis had the highest (9.2 ± 3.7)/(4.6 ± 1.9 torr). Surgical valve opening area (SOA) varied with the 25‐mm Mitris having the largest SOA (2.4 ± 0.15 cm(2)) followed by the 27‐mm Mosaic (2.04 ± 0.23 cm(2)) and the 27‐mm Epic (1.8 ± 0.27 cm(2)) valve. Bench device orthogonal internal diameter measurements did not match manufacturer device size labeling: 25‐mm Mitris (23 × 23 mm), 27‐mm Mosaic (23 × 22 mm), 27‐mm Epic (21 × 21 mm). CONCLUSIONS: Current advertisement/packaging of commercial surgical mitral valves is not uniform. This study demonstrates marked variations in hemodynamics, valve opening area and anatomic dimensions between similar sized mitral bioprostheses. These data suggest a critical need for standardization and close scientific evaluation of surgical mitral bioprostheses to ensure optimal clinical outcomes

Initial in-human experience with the conveyor cardiovascular system for the delivery of large profile transcatheter valve devices

OBJECTIVES: To determine the safety and efficacy of the conveyor cardiovascular system (CCS) to facilitate the delivery of large profile transcatheter valve devices. BACKGROUND: Transcatheter valve devices rely on force provided by the operator to be delivered to their intended position. This delivery may be challenging in a variety of anatomic scenarios. The ability to provide steering from the tip of the device by forming an arterial venous loop may help overcome these challenges. METHODS: Between May, 2019 and October, 2020, five patients were recruited for delivery of transcatheter valve devices with the CCS. These patients were deemed by the operators to have challenging anatomy which could make conventional valve delivery difficult or impossible. These patients were recruited as part of an FDA approved early feasibility study or through an institutional review board approved compassionate use protocol. RESULTS: Three patients underwent transcatheter mitral valve replacement with a SAPIEN-3 valve. One patient each underwent transcatheter aortic valve (TAVR) implantation with a SAPIEN 3 and 1 patient underwent TAVR implantation with a Lotus valve. All patients underwent successful implantation of the valve and removal of the CCS and valve delivery systems. There was no more than trivial mitral regurgitation post procedure in any patient and there was no more than trivial paravavular leak. There were no major in-hospital complications. CONCLUSIONS: The CCS facilitates the delivery of large profile transcatheter valve devices in challenging anatomic scenarios. Further studies are needed with additional valve technologies

Comparative differences of mitral valve-in-valve implantation: A new mitral bioprosthesis versus current mosaic and epic valves

OBJECTIVE: Evaluate transcatheter mitral valve replacement (TMVR) valve-in-valve (VIV) outcomes in three different mitral bioprostheses (of comparable measured internal diameters) under stable hemodynamic and surgical conditions by bench, echocardiographic, computerized tomography (CT), and autopsy comparisons pre- and post-valve implantation in a porcine model under matched controlled conditions. BACKGROUND: Impact of surgical bioprosthesis design on TMVR VIV procedures is unknown. METHODS: Fifteen similar-sized Yorkshire pigs underwent pre-procedural CT screening. Twelve had consistent anatomic features and underwent implantation of mitral bioprostheses. Four valves from each of three manufacturers were implanted in randomized fashion: 27-mm Epic, 27-mm Mosaic, and 25-mm Mitris, followed by TMVR VIV with 26 Edwards Sapien3. Post-VIV, suprasternal TEE studies were performed to assess hemodynamic function, followed by a gated contrast CT. After euthanasia, animals underwent necropsy for anatomic evaluation. RESULTS: All 12 animals had successful VIV implantation with no study deaths. The post vivMitris (3.77 ± 0.36)/(2.2 ± 0.25 mmHg) had the lowest peak/mean trans-mitral gradient and the vivEpic the highest (15.5 ± 2.55)/(7.09 ± 1.13 mmHg). All THVs (transcatheter heart valves) had greatest deformation within the center of the THV frame; with the smallest waist opening area in the vivEpic (329 ± 35.8 mm(2) ) and greatest in the vivMitris (414 ± 33.12 mm(2) ). Bioprosthetic frames without obvious radiopaque markers resulted in the most ventricular implantation of the THV\u27s anteroseptal frame (Epic: -4.52 ± 0.76 mm), versus the most radiopaque bioprosthesis (Mitris: -1.18 ± 2.95 mm), and higher peak LVOT gradients (Epic: 4.82 ± 1.61 mmHg; Mitris: 2.91 ± 1.47 mmHg). CONCLUSIONS: The current study demonstrates marked variations in hemodynamics, THV opening area, and anatomic dimensions among measured similarly sized mitral bioprostheses. These data suggest a critical need for understanding the potential impact of variations in bioprosthesis design on TMVR VIV clinical outcomes

Surgical complications of transaxillary arteriography: A case-control study

AbstractPurpose: The purpose of this study was to review the complications of transaxillary arteriography (TRAX), determine clinical factors associated with their occurrence, and define optimal treatment methods.Methods: A retrospective review of 842 consecutive TRAX studies performed in a large, urban, tertiary care, academic medical center was undertaken. Patients with complications were compared with a concurrent randomized control group without complications with the use of a multivariate analysis model. Results of operative therapy for nerve injury were compared with those of nonoperative therapy.Results: Nineteen (2.3%) complications were identified including 14 nerve injuries, four expanding hematomas/pseudoaneurysms without neurologic deficit, and one puncture site thrombosis. Several statistically significant or suggestive findings associated with the occurrence of complications were identified: female sex (odds ratio [OR[ = 4.7), systolic blood pressure ≥150 mm Hg at the conclusion of TRAX (OR = 9.5), periprocedural systemic heparin anticoagulation (OR = 7.9), concomitant use of intraarterial thrombolysis or percutaneous angioplasty (OR = 12.0), and duration of procedure ≥90 minutes (OR = 4.0). Patients who underwent prompt exploration (≤4 hours from symptom onset) for nerve injuries were more likely to have complete resolution of their neurologic deficits (five of six patients) than those who were observed or underwent delayed operation (three of eight patients) (OR = 8.3).Conclusions: Aggressive treatment of post-TRAX hypertension, limitation of TRAX duration, delay of postprocedure anticoagulation, and use of alternative sites for arterial puncture in female patients or patients undergoing catheter-based intervention may reduce the incidence of TRAX-related complications. In patients who have neurologic deficits prompt surgical exploration of the puncture site with decompression of the involved nerve(s) may reduce the incidence of prolonged deficits. (J Vasc Surg 1996;23:844-50.

Allopurinol improves myocardial reperfusion injury in a xanthine oxidase-free model

The ability of allopurinol to protect against reperfusion injury in the heart has usually been attributed to its xanthine oxidase (XO)- inhibiting properties. Human myocardium how- ever has exhibited low levels of XO activity. To investigate the effects of allopurinol in an XO-free model and determine whether pretreat- ment is necessary 12 domestic pigs (15 kg to 20 kg) underwent occlusion of the left circum- flex for 8 minutes followed by reperfusion for 4 hours. One group received allopurinol infusion (5 mg/kg IV) at occlusion over 45 minutes and a control group (n = 6) received a saline infusion (same volume). Left ventricular and aortic pressure electrocardiograms and regional wall motion (sonomicrometry) were monitored throughout the process. Regional blood flow (microspheres) were obtained before during and 5 10 and 30 minutes after ischemia. Occlusion decreased transmural flow at the midpapillary level by 75% (0.28 versus 1.10 mUminute/g). The allopurinol-treated group exhibited a mild generalized hyperemia at 5 minutes (ischemic zone: 1.44 versus 1.10 mU min/g which returned to control levels at 10 and 30 minutes. In contrast the control group was associated with only 80% restoration of resting blood flow at 5 minutes (0.84 versus 1.10 mUmin/g) which stabilized at 63% of control levels at 10 and 30 minutes. When evaluated for the propensity of arrhythmias using an arbitrary arrhythmia score the al- lopurinol group demonstrated no myocardial ectopy when compared with the focal ectopy routinely encountered in the control group at all time intervals. Since pigs have no detectable levels of XO activity allopurinol must exert its protectant effect during myocardial reperfu- sion by an alternative mechanism. Because protection was evident without pretreatment beneficial effects may not necessarily be the result of allopurinol degradation products; therefore pretreatment with allopurinol may not be necessary. These results are clinically important when considering the use of allopuri- nol in an emergent coronary angioplasty or coronary artery bypass grafting. Originally published Journal of the National Medical Association Vol. 87 No. 7 July 199