Brett Oestreich

Role of Epinephrine and Extracorporeal Membrane Oxygenation in the Management of Ischemic Refractory Ventricular Fibrillation: A Randomized Trial in Pigs

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Avoiding the Learning Curve for Transcatheter Aortic Valve Replacement

Objectives. To evaluate whether collaboration between existing and new transcatheter aortic valve replacement (TAVR) programs could help reduce the number of cases needed to achieve optimal efficiency. Background. There is a well-documented learning curve for achieving procedural efficiency and safety in TAVR procedures. Methods. A multidisciplinary collaboration was established between the Minneapolis VA Medical Center (new program) and the University of Minnesota (established program since 2012, n = 219) 1 year prior to launching the new program. Results. 269 patients treated with TAVR (50 treated in the first year at the new program). Mean age was 76 (±18) years and STS score was 6.8 (±6). Access included transfemoral (n = 35, 70%), transapical (n = 8, 16%), transaortic (n = 2, 4%), and subclavian (n = 5, 10%) types. Procedural efficiency (procedural time 158 ± 59 versus 148 ± 62, p = 0.27), device success (96% versus 87%, p = 0.08), length of stay (5 ± 3 versus 6 ± 7 days, p = 0.10), and safety (in hospital mortality 4% versus 6%, p = 0.75) were similar between programs. We found no difference in outcome measures between the first and last 25 patients treated during the first year of the new program. Conclusions. Establishing a partnership with an established program can help mitigate the learning curve associated with these complex procedures.

Sodium nitroprusside enhanced cardiopulmonary resuscitation improves short term survival in a porcine model of ischemic refractory ventricular fibrillation

INTRODUCTION Sodium nitroprusside (SNP) enhanced CPR (SNPeCPR) demonstrates increased vital organ blood flow and survival in multiple porcine models. We developed a new, coronary occlusion/ischemia model of prolonged resuscitation, mimicking the majority of out-of-hospital cardiac arrests presenting with shockable rhythms. HYPOTHESIS SNPeCPR will increase short term (4-h) survival compared to standard 2015 Advanced Cardiac Life Support (ACLS) guidelines in an ischemic refractory ventricular fibrillation (VF), prolonged CPR model. METHODS Sixteen anesthetized pigs had the ostial left anterior descending artery occluded leading to ischemic VF arrest. VF was untreated for 5min. Basic life support was performed for 10min. At minute 10 (EMS arrival), animals received either SNPeCPR (n=8) or standard ACLS (n=8). Defibrillation (200J) occurred every 3min. CPR continued for a total of 45min, then the balloon was deflated simulating revascularization. CPR continued until return of spontaneous circulation (ROSC) or a total of 60min, if unsuccessful. SNPeCPR animals received 2mg of SNP at minute 10 followed by 1mg every 5min until ROSC. Standard ACLS animals received 0.5mg epinephrine every 5min until ROSC. Primary endpoints were ROSC and 4-h survival. RESULTS All SNPeCPR animals (8/8) achieved sustained ROSC versus 2/8 standard ACLS animals within one hour of resuscitation (p=0.04). The 4-h survival was significantly improved with SNPeCPR compared to standard ACLS, 7/8 versus 1/8 respectively, p=0.0019. CONCLUSION SNPeCPR significantly improved ROSC and 4-h survival compared with standard ACLS CPR in a porcine model of prolonged ischemic, refractory VF cardiac arrest.

Computed tomography (CT) assessment of the membranous septal anatomy prior to transcatheter aortic valve replacement (TAVR) with the balloon-expandable SAPIEN 3 valve

OBJECTIVES The lower limit of the membranous septum (MS) is considered an anatomic landmark for the emergence of the Bundle of His into the left ventricle. Computed tomography (CT) assessment of MS anatomy may provide useful information about the risk of conduction abnormalities following transcatheter aortic valve replacement (TAVR). METHODS AND RESULTS The study included 102 consecutive patients undergoing TAVR with the Edwards Sapien 3 (S3) valve. Using pre-TAVR CT and post-procedure angiography we evaluated for the presence of calcium in the left ventricular outflow tract (LVOT), calcium depth (CD), implantation depth (ID) and MS length. The MS length minus the prosthesis ID was calculated (Delta MSID). Outcomes included new left bundle branch block (LBBB) or permanent pacemaker (PPM) within 30days. Seventeen patients (17%) received a PPM and 28 (27%) developed new LBBB following TAVR. Mean (±SD) MS length and delta MSID were 7.5mm (2) and 0.9mm (4.5), respectively. Twenty-one patients (20%) had calcium in the device landing zone and the mean (SD) CD was 6.8mm (±4). Calcium in the device landing zone (37% versus 16%, p=0.02) and implantation depth (6mm (4-8) versus 4mm (4-5), p=0.02) predicted new conduction abnormalities after TAVR. CONCLUSIONS The presence of calcium in the device landing zone is associated with increased risk of conduction abnormalities after TAVR with S3. In such cases, a more aortic deployment of the prosthesis may be warranted.

Outcomes of intermediate-risk patients treated with transcatheter and surgical aortic valve replacement in the Veterans Affairs Healthcare System: A single center 20-year experience

Transfemoral transcatheter aortic valve replacement (TAVR) was superior to surgical aortic valve replacement (SAVR) in the placement of aortic transcatheter valves (PARTNER) 2A trial (P2). The generalizability of the trial results to the broader population of patients with intermediate surgical risk remains unknown.

Exposure to glucocorticoids prior to transcatheter aortic valve replacement is associated with reduced incidence of high-degree AV block and pacemaker

BACKGROUND Tissue edema and inflammation, which occur at the device landing zone during valve deployment, may contribute to the pathophysiology of conduction abnormalities after transcatheter aortic valve replacement (TAVR). We hypothesized that exposure to glucocorticoids prior to TAVR will reduce the incidence of conduction abnormalities requiring PPM implantation after TAVR. METHODS We included 167 consecutive patients treated with TAVR at the Minneapolis VA Medical Center and University of Minnesota. Exposure to glucocorticoids was assessed by linking electronic medical and pharmacy records. The primary outcome was a new PPM within 30 days of the index TAVR procedure. RESULTS Of the 167 patients included, 16 (9.5%) were exposed to glucocorticoids prior to TAVR. No differences in age, STS score, pre-existing right bundle branch block, implantation depth or valve type were seen among patients exposed to glucocorticoids versus those who were unexposed. Patients exposed to glucocorticoids were more likely to have moderate/severe COPD (43% versus 18%, p < 0.01). The cumulative incidence of PPM implantation at 30-days after TAVR was 18%. None of the patients exposed to glucocorticoids required a PPM while 30 (19%) of the unexposed patients did (p = 0.04). CONCLUSIONS Exposure to glucocorticoids prior to TAVR may be associated with reduced incidence of PPM requirement though larger studies are needed to support these findings. Tissue edema and inflammation may be significant contributors to the pathophysiology of conduction abnormalities after TAVR and could represent a therapeutic target.

CALCIFICATION IN THE BASAL SEPTUM, BUT NOT MEMBRANOUS SEPTAL LENGTH, PREDICTS AV CONDUCTION DISTURBANCE AND PACEMAKER IMPLANTATION FOLLOWING TRANSCATHETER AORTIC VALVE REPLACEMENT WITH A BALLOON-EXPANDABLE VALVE (S3)

Background: The lower end of the membranous septum (MS) represents an anatomic landmark for the emergence of the His Bundle into the left ventricle. Computed tomography (CT) assessment of the membranous septal anatomy prior to transcatheter aortic valve replacement (TAVR) may provide information

Routine use of anticoagulation after transcatheter aortic valve replacement: Initial safety outcomes from a single-center experience

BACKGROUND Subclinical leaflet thrombosis (SCLT) can be seen in up to 12% of patients after transcatheter aortic valve replacement (TAVR). Anticoagulation appears to prevent and reverse SCLT but concerns exist about bleeding risk. METHODS Our program adopted a strategy of routine anticoagulation after TAVR, starting warfarin on post-procedure day 0 and continuing for 3months in 10/2015. We report the initial safety and efficacy outcomes of this approach. Bleeding events were assessed using Valve Academic Research Consortium (VARC) and Bleeding Academic Research Consortium (BARC) definitions. RESULTS The median (IQR) age of the population (n=191) was 82years (72-87) and the median (IQR) STS score was 5.6% (3-8). A total of 101 (53%) patients were discharged on anticoagulation (warfarin 97%) while 90 (47%) received antiplatelet therapy alone. The mean duration of anticoagulation therapy was 81±17 days. During follow-up 7 patients (4%) had a stroke or TIA, 3 (3%) in the anticoagulation group and 4 (4%) in the antiplatelet group (p=0.71). A total of 8 patients (4.2%) had BARC bleeding events during follow-up, 3 patients in the anticoagulation group (2.9%) and 5 in the antiplatelet group (5.5%, p=0.48). All bleeding events (VARC and BARC) were numerically lower in the anticoagulation group (8% versus 13%, p=0.20). CONCLUSIONS A strategy of routine anticoagulation for 3-months after TAVR is well tolerated and associated with similar or lower bleeding risk compared to antiplatelet therapy.