Virtual reality to predict paravalvular leak in bicuspid severe aortic valve stenosis in transcatheter aortic valve implants.

OBJECTIVES: Severe aortic stenosis (AS) in bicuspid aortic valves (BAV) is associated with an increased risk of paravalvular leak (PVL) after a transcatheter aortic valve replacement (TAVR). Virtual reality (VR) has been shown to be an effective tool in surgical training, but its utility in clinical practice has not been studied. Here we present the first study to evaluate the use of VR simulation in pre-procedure planning and prediction of PVL in TAVR in patients with severe BAV AS. METHODS: Twenty-two patients with severe BAV AS undergoing TAVR between 2014 and 2018 at the University of Minnesota were included in the study. VR simulation of TAVR implants was performed and implants were analyzed for PVL. The primary endpoint was the percent circumference of valve malapposition in VR as compared to the severity of PVL on post-procedure echocardiography. RESULTS: The median age was 78.26 years (IQR 63.77-86.79) and 40.9% (n = 9) were female. Our VR model accurately predicted the presence and absence of PVL in all patients (17/17 and 5/5, respectively). The mean circumferential PVL was 3.73 % ± 7.71. The receiver operator characteristic curve showed an area under the curve of 0.83 (0.59-1.00, P = .03) for malapposition in the VR-TAVR simulated model. CONCLUSIONS: VR-TAVR implantation may predict PVL in severe BAV AS undergoing TAVR.

Effect of Combination of Balloon Pulmonary Angioplasty and Medical Therapy on Reverse Right Ventricular Remodeling and Hemodynamics in Chronic Thromboembolic Pulmonary Hypertension.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is a progressive and debilitating disorder that results from incomplete resolution of vascular obstructions resulting in pulmonary hypertension. Surgical pulmonary thromboendarterectomy (PTE) is the treatment of choice for CTEPH. Unfortunately, many CTEPH patients are ineligible for PTE or do not have access to an expert surgical center. Medical therapy imparts important symptomatic and exercise benefits for CTEPH patients, but it does not extend survival. Balloon pulmonary angioplasty (BPA) is an emerging transcatheter approach that is both safe and efficacious. However, the potential synergy between upfront BPA and medical therapy treatment approaches in patients with inoperable CTEPH is unknown. Here, we evaluated how the combination of BPA and medical therapy compared to medical therapy alone in a newly established BPA program. METHODS: Twenty-one patients with inoperable or residual CTEPH were evaluated in this single-center observational study. Ten patients underwent upfront BPA and medical therapy while 11 patients were treated with medical therapy alone. Hemodynamic and echocardiographic assessments were performed at baseline and at least 1 month after completion of therapy. Continuous variables were compared using t-test or Mann-Whitney U-test. Categorical variables were analyzed with Chi squared and Fisher's exact test where appropriate. RESULTS: Combination therapy significantly reduced mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR), but medical therapy only significantly lowered PVR. Comprehensive echocardiographic analysis revealed a more robust reverse right ventricular (RV) remodeling effect and augmentation of RV function with combination therapy. At the end of study, the combination therapy group had lower mPAP and PVR and better RV function. Importantly, there were no significant adverse effects in patients treated with BPA. CONCLUSION: Combination therapy significantly improves hemodynamics and RV function in inoperable CTEPH while carrying an acceptable risk profile, even in a newly developed program. Further studies comparing upfront combination therapy to medical therapy with larger, long-term, and randomized approaches should be considered.

High-Temperature Behavior of Laser Electrodispersion-Prepared Pd/ZSM-5 Hydrocarbon Traps under CO Oxidation Conditions.

Zeolites and metal-doped zeolites are now widely considered as low-temperature hydrocarbon traps to be a part of emission control systems in automobiles. However, due to the high temperature of exhaust gases, the thermal stability of such sorbent materials is of great concern. To avoid the thermal instability problem, in the present work, laser electrodispersion was used to deposit Pd particles on the surface of ZSM-5 zeolite grains (SiO2/Al2O3 = 55 and SiO2/Al2O3 = 30) to obtain Pd/ZSM-5 materials with a Pd loading as low as 0.03 wt.%. The thermal stability was evaluated in a prompt thermal aging regime involving thermal treatment at temperatures up to 1000 °C in a real reaction mixture (CO, hydrocarbons, NO, an excess of O2, and balance N2) and a model mixture of the same composition with the exception of hydrocarbons. Low-temperature nitrogen adsorption and X-ray diffraction analysis were used to examine the stability of the zeolite framework. Special attention was paid to the state of Pd after thermal aging at varied temperatures. By means of transmission electron microscopy, X-ray photoelectron spectroscopy, and diffuse reflectance UV-Vis spectroscopy, it was shown that palladium, having been initially located on the surface of zeolite, undergoes oxidation and migrates into the zeolite's channels. This enhances the trapping of hydrocarbons and their subsequent oxidation at lower temperatures.

Studies on High-Temperature Evolution of Low-Loaded Pd Three-Way Catalysts Prepared by Laser Electrodispersion.

Pd/Al2O3 catalyst of the "crust" type with Pd loading of 0.03 wt.% was prepared by the deposition of 2 nm Pd particles on the outer surface of the alumina support using laser electrodispersion (LED). This technique differs from a standard laser ablation into a liquid in that the formation of monodisperse nanoparticles occurs in the laser torch plasma in a vacuum. As is found, the LED-prepared catalyst surpasses Pd-containing three-way catalysts, obtained by conventional chemical synthesis, in activity and stability in CO oxidation under prompt thermal aging conditions. Thus, the LED-prepared Pd/Al2O3 catalyst showed the best thermal stability up to 1000 °C. The present research is focused on the study of the high-temperature evolution of the Pd/Al2O3 catalyst in two reaction mixtures by a set of physicochemical methods (transmission electron microscopy, X-ray photoelectron spectroscopy, and diffuse reflectance UV-vis spectroscopy). In order to follow the dispersion of the Pd nanoparticles during the thermal aging procedure, the testing reaction of ethane hydrogenolysis was also applied. The possible reasons for the high stability of LED-prepared catalysts are suggested.

The native aortic valve reduces paravalvular leak in TAVR patients.

Background: Paravalvular leak (PVL) is a frequent TAVR complication. Prospective identification of patients who are likely to develop PVL after TAVR would likely lead to improved outcomes. Prior studies have used geometric characteristics to predict the likelihood of PVL development, but prediction and quantification has not been done. One of the reasons is that it is difficult to predict the mechanical deformation of the native diseased aortic valve prior to implantation of the prosthetic valve, as existing calcifications likely contribute to the seal between the prosthetic valve and the aortic annulus. However, the relatively amount the native valve plays in preventing PVL is unknown. Methods: A retrospective chart review was conducted identifying patients with mild or greater PVL. One patient who had substantial PVL was identified and a 3D printed (pre-TAVR) aortic root was created. Balloon-expandable TAVR stent frames were implanted within the 3D printed root and a new model was created. Using this geometry, computational fluid dynamics (CFD) simulations were done to quantify PVL. The PVL flow path was iteratively decreased to simulate the space occupied by a crushed native aortic valve and PVL was quantified. Results: PVL was found to decrease as the space occupying the PVL area increased, demonstrating that the native aortic valve contributes to reducing regurgitation. CFD simulations demonstrated that within the patient analyzed, the native valve occupies between 3-40% of the PVL pathway. Conclusion: A priori techniques that predict the development of post TAVR PVL should account for the native diseased valve as our simulations demonstrate that it plays a role in reducing PVL.

Effects of a Mixed-Reality Headset on Procedural Outcomes in the Cardiac Catheterization Laboratory.

BACKGROUND: Mixed reality head-mounted displays (MR-HMD) are a novel and emerging tool in healthcare. There is a paucity of data on the safety and efficacy of the use of MR-HMD in the cardiac catheterization laboratory (CCL). We sought to analyze and compare fluoroscopy time, procedure time, and complication rates with right heart catheterizations (RHCs) and coronary angiographies (CAs) performed with MR-HMD versus standard LCD medical displays. METHODS: This is a non-randomized trial that included patients who underwent RHC and CA with MR-HMD between August 2019 and January 2020. Their outcomes were compared to a control group during the same time period. The primary endpoints were procedure time, fluoroscopy time, and dose area product (DAP). The secondary endpoints were contrast volume and intra and postprocedural complications rate. RESULTS: 50 patients were enrolled in the trial, 33 had a RHC done, and 29 had a diagnostic CA performed. They were compared to 232 patients in the control group. The use of MR-HMD was associated with a significantly lower procedure time (20 min (IQR 14-30) vs. 25 min (IQR 18-36), p = 0.038). There were no significant differences in median fluoroscopy time (1.5 min (IQR 0.7-4.9) in the study group vs. 1.3 min (IQR 0.8-3.1), p = 0.84) or median DAP (165.4 mGy·cm2 (IQR 13-15,583) in the study group vs. 913 mGy·cm2 (IQR 24-6291), p = 0.17). There was no significant increase in intra- or post-procedure complications. CONCLUSION: MR-HMD use is safe and feasible and may decrease procedure time in the CCL.

A retrospective study on the trends in surgical aortic valve replacement outcomes in the post-transcatheter aortic valve replacement era.

Background and Aims: Transcatheter aortic valve replacement (TAVR) is the mainstay of treatment of inoperable and severe high-risk aortic stenosis and is noninferior to surgical aortic valve replacement (SAVR) for low-risk and intermediate-risk patients as well. We aim to compare the valve size, area, and transaortic mean gradients in SAVR patients before and after the implementation of TAVR since being approved by the Food and Drug Administration  in 2011. Methods: Patients who underwent a bioprosthetic SAVR placement were divided into two groups based on the date of procedure: the early pre-TAVR implementation group (years 2011-2012) and the contemporary post-TAVR group (years 2019-2020). The primary endpoint was the mean gradient across the aortic valve within 16 months of surgery. The secondary endpoints included the difference in valve size and various aortic valve echocardiographic variables. Results: One hundred and thirty patients had their valves replaced in the years 2011-2012 and 134 in the years 2019-2020. The early group had a significantly higher mean gradient (median of 13 mmHg [interquartile range, IQR: 9.3-18] vs. 10 mmHg [IQR: 7.5-13.1], p = 0.001) and a smaller median effective orifice area index (0.8 cm2/m2 [IQR: 0.6-1] vs. 1.1 cm2/m2 [IQR: 0.8-1.3], p < 0.001). The median valve size was significantly smaller in the early group (median of 21 mm [IQR: 21-23] vs. 23 mm [IQR: 22.5-25], p < 0.001). Conclusion: In the contemporary era, surgical patients receive larger valves which translates into lower mean gradients, larger valve area, and lower rates of patient-prosthesis mismatch than in previous years before the routine introduction of TAVR.

Invasive hemodynamics are equivocal for functional outcomes after MitraClip.

OBJECTIVES: To evaluate invasive hemodynamics in assessing MC therapy success as well as evaluate its effectiveness as a predictor of functional outcomes. BACKGROUND: Mitral regurgitation grade is a poor predictor of functional outcomes after a MitraClip. There is a paucity of data on invasive hemodynamics as a predictor of outcomes. METHODS: Sixty-nine patients underwent MC between 2015 and 2018 at the University of Minnesota Medical Center and were retrospectively analyzed. Invasive hemodynamics were performed before and after device deployment with transesophageal echocardiographic guidance. Statistical analysis was performed using STATA version 16. Student's t test was used for continuous variables and Pearson's chi-squared test for categorical variables. Mann-Whitney test was performed for continuous variables where data were not normally distributed. Logistic and linear regression were used to investigate relationships between variables and outcomes. RESULTS: A total of 69 patients were included in the study. The mean age was 83 (75-87) years and 38 (55%) were male. Eighty-one percentage had >/= NYHA III symptoms. Eighty-seven percentage had severe MR. Pulmonary capillary wedge pressure was 20 (15-24). Overall, there was significant improvement in left atrial pressure including mean left atrial pressure index, MR, and NYHA class after MC (<.001). There was no significant association between invasive hemodynamics (including left atrial mean pressure index or its reduction rate) and functional outcomes (p = NS). MR grade was also not predictive of functional outcomes. CONCLUSION: Left atrial pressure may not be a significant predictor of functional outcomes, and, in isolation, may not be an improvement over MR grade.

3-Dimensional printing to predict paravalvular regurgitation after transcatheter aortic valve replacement.

BACKGROUND: There is no effective method to predict paravalvular regurgitation prior to transcatheter aortic valve replacement (TAVR). METHODS: We retrospectively analyzed pre-TAVR computed tomography (CT) scans of 20 patients who underwent TAVR for severe, calcific aortic stenosis and subsequently printed 3-dimensional (3D) aortic root models of each patient. Models were printed using Ninjaflex thermoplastic polyurethane (TPU) (Ninjatek Manheim, PA) and TPU 95A (Ultimaker, Netherlands) on Ultimaker 3 Extended 3D printer (Ultimaker, Netherlands). The models were implanted at nominal pressure with same sized Sapien balloon-expandable frames (Edwards Lifesciences, CA) as received in-vivo. Ex-vivo implanted TAVR models (eTAVR) were scanned using Siemens SOMATOM flash dual source CT (Siemens, Malvern, PA) and then analyzed with Mimics software (Materialize NV, Leuven, Belgium) to evaluate relative stent appositions. eTAVR were then compared to post-TAVR echocardiograms for each patient to assess for correlations of identified and predicted paravalvular leak (PVL) locations. RESULTS: A total of 20 patients (70% male) were included in this study. The median age was 77.5 (74-83.5) years. Ten patients were characterized to elicit mild (9/10) or moderate (1/10) PVL, and 10 patients presented no PVL. In patients with echocardiographic PVL, eTAVR 3D model analyses correctly identified the site of PVL in 8/10 cases. In patients without echocardiographic PVL, eTAVR 3D model analyses correctly predicted the lack of PVL in 9/10 cases. CONCLUSION: 3D printing may help predict the potential locations of associated PVL post-TAVR, which may have implications for optimizing valve selection and sizing.

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.

Validation of STS/ACC TVT-TAVR Score in Veterans Undergoing Transcatheter Aortic Valve Replacement.

BACKGROUND: The Society of Thoracic Surgeons (STS)/American College of Cardiology (ACC) transcatheter valve therapy (TVT) transcatheter aortic valve replacement (TAVR) score was developed to predict in-hospital mortality in patients undergoing commercial TAVR in the United States. Veterans Affairs (VA) hospitals are not included in the TVT registry. METHODS: The STS/ACC TVT-TAVR score was estimated in 195 veterans undergoing TAVR from 2015-2017. Discrimination was estimated by calculating the area under the receiver operating characteristics curve (AUC) for two outcomes of interest: in-hospital and 30-day mortality. The cohort was then divided into quartiles of TAVR and STS predicted risk of mortality (PROM) scores and long-term mortality was assessed with Kaplan-Meier curves. RESULTS: The mean age of the cohort was 77 ± 8 years and the population was 99% males. The median TAVR and STS-PROM risk scores were 3.1 (interquartile range [IQR], 2.1-5.1) and 4.5 (IQR, 2.6-7.4), respectively. Observed in-hospital and 30-day mortality rates were 2.6% and 4.6%, respectively. The AUCs for the TAVR risk score were 0.68 and 0.64 for in-hospital and 30-day mortality, respectively. During a mean follow-up period of 1.9 years, a total of 37 patients (20%) died. Long-term survival was similar in different quartiles of STS-PROM scores (P=.52). In contrast, patients in the highest quartile of TAVR risk score (8.4; IQR, 5.8-9.9) had significantly worse survival (P<.01). This group included 20 out of the 37 deaths (>50%). CONCLUSIONS: Developed and validated in commercial United States cases, the TAVR risk score has a similar performance in the veteran population for predicting short-term outcomes. In addition, the TAVR score predicts long-term mortality. Our results have implications for optimal patient selection.

Transcatheter Aortic Valve Replacement Improves Health Status in Elderly Veterans.

BACKGROUND: United States veterans have substantially worse baseline health status than the general population, which may limit the health benefits of transcatheter aortic valve replacement (TAVR). The aim of this study is to quantify the health benefits of TAVR in veterans undergoing the procedure within the United States Department of Veterans Affairs (VA) health-care system. METHODS: We prospectively evaluated heath status in 131 elderly veterans undergoing TAVR in the VA healthcare system between 2015 and 2017. Health status was assessed at baseline and 30 days post procedure using the Kansas City Cardiomyopathy Questionnaire 12 (KCCQ-12). Totals and domain-specific (physical limitation, symptoms, quality of life, and social limitation) health statuses were measured and analyzed with a paired t-test. We also conducted stratified analysis by baseline New York Heart Association functional class and N-terminal pro-b type natriuretic peptide levels. RESULTS: Mean patient age was 77 ± 8 years and average Society of Thoracic Surgeons (STS) score was 4.4 (interquartile range, 3-7). Transfemoral access and balloon-expandable valves were used in 118 cases (92%) and 108 cases (83%), respectively. At baseline, overall health status was poor (overall score, 43 ± 19). After TAVR, significant improvements in overall health status (30 ± 18) and domain-specific health status were seen (improvements in physical limitation, 12 ± 20; symptoms, 23 ± 23; quality of life, 20 ± 17; social limitation, 22 ± 21; all P<.001). The majority of patients (88%) had moderate to large improvements in health status. A favorable outcome (alive with KCCQ-12 overall score >60 at 30 days) was seen in 78% of patients. CONCLUSION: Among elderly veterans with severe aortic stenosis, TAVR is associated with significant improvements in short-term health status.

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.

BACKGROUND: 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. OBJECTIVE: To compare the outcomes of SAVR and TAVR among patients with intermediate surgical risk treated in the VA Healthcare System. METHODS: We retrospectively analyzed the clinical characteristics and outcomes on all SAVR (1987-2014) and TAVR procedures (2015-2017) performed at the Minneapolis VA Healthcare System. Patients were divided into three groups based on their estimated 30-day mortality risk. The primary outcome was a composite of death or stroke at 30-days. RESULTS: A total of 1,049 patients underwent SAVR with (n = 468, 45%) or without CABG (n = 581, 55%) and 110 underwent TAVR during the study period. Intermediate-risk patients represented 29.4% and 40% of patients undergoing SAVR and TAVR, respectively. The predicted 30-day mortality risk of intermediate-risk patients was 5.5% for the SAVR group and 5.2% for the TAVR group (P = 0.54). The observed combined rate of stroke or death at 30-days for intermediate-risk patients treated with SAVR and TAVR was 11% and 2.2%, respectively (P = 0.05). The results for SAVR and TAVR at the VA were comparable to the P2 trial and STS database (all P = NS). The results did not change when the analysis was restricted to a more contemporary (2005-2014) surgical cohort or isolated SAVR. The number needed to treat to prevent one death/stroke with TAVR was 10. CONCLUSIONS: Adoption of TAVR as the preferred treatment modality in intermediate-risk patients may result in significant improvements in morbidity and mortality.

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 transcatheter aortic valve replacement using a minimalist approach.

BACKGROUND: Transcatheter Aortic Valve Replacement (TAVR) is increasingly performed using a minimalist approach under monitored anesthesia care (MAC). The safety of this approach remains controversial and adoption has been low in the US. METHODS: The study cohort was comprised of 130 patients (98% male) who underwent TAVR between 4/2015 and 4/2017 at the Minneapolis VA. We compared the outcomes of 81 patients who underwent TAVR using a standard approach (standard TAVR) and 49 who underwent TAVR using a minimalist approach (minimalist TAVR). Outcome measures included device and procedural success, procedural efficiency, length of intensive care unit (ICU) and hospital stay, procedural complications and hospital readmissions. RESULTS: Mean age was 80 (±9) years and median (IQR) STS score was 5 (4-6). Access included transfemoral (n = 111, 85%) and alternative (n = 19, 15%). Minimalist TAVR was associated with reduced procedural time: median 101 min (IQR: 78-135) versus 127 min (IQR: 97-182, p = 0.03), fluoroscopy time: median 18 min (IQR: 12-26) versus 24 min (IQR: 16-38), p = 0.001), contrast volume 90 ml (IQR: 70-120 ml) versus 140 ml (IQR: 86-213 ml, p < 0.001). CONCLUSIONS: A minimalistic approach to TAVR is associated with improved procedural efficiency and reduced length of stay without compromising procedural success or clinical outcomes.

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.

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.

Myocardial perfusion pattern for stratification of ischemic mitral regurgitation response to percutaneous coronary intervention.

OBJECTIVE: Ischemic mitral regurgitation (MR) is common, but its response to percutaneous coronary intervention (PCI) is poorly understood. This study tested the utility of myocardial perfusion imaging (MPI) for the stratification of MR response to PCI. METHODS: MPI and transthoracic echocardiography (echo) were performed among patients undergoing PCI. MPI was used to assess stress/rest myocardial perfusion. MR was assessed via echo (performed before and after PCI). RESULTS: A total of 317 patients with abnormal myocardial perfusion on MPI underwent echo 25±39 days before PCI. MR was present in 52%, among whom 24% had advanced (≥moderate) MR. MR was found to be associated with left ventricular (LV) chamber dilation on MPI and echo (both P<0.001). The magnitude of global LV perfusion deficits increased in relation to MR severity (P<0.01). Perfusion differences were greatest for global summed rest scores, which were 1.6-fold higher among patients with advanced MR versus those with mild MR (P=0.004), and 2.4-fold higher versus those without MR (P<0.001). In multivariate analysis, advanced MR was found to be associated with a fixed perfusion defect size on MPI [odds ratio 1.16 per segment (confidence interval 1.002-1.34), P=0.046], independent of LV volume [odds ratio 1.10 per 10 ml (confidence interval 1.04-1.17), P=0.002]. Follow-up via echo (1.0±0.6 years) demonstrated MR to decrease (≥1 grade) in 31% of patients and increase in 12% of patients. Patients with increased MR after PCI had more severe inferior perfusion defects on baseline MPI (P=0.028), whereas defects in other distributions and LV volumes were similar (P=NS). CONCLUSION: The extent and distribution of single-photon emission computed tomography-evidenced myocardial perfusion defects impact MR response to revascularization. An increased magnitude of inferior fixed perfusion defects predicts post-PCI progression of MR.

Left ventricular geometric remodeling in relation to non-ischemic scar pattern on cardiac magnetic resonance imaging.

Left ventricular (LV) remodeling and myocardial fibrosis have been linked to adverse heart failure outcomes. Mid wall late gadolinium enhancement (MW-LGE) on cardiac magnetic resonance (CMR) imaging is well-associated with non-ischemic cardiomyopathy (NICM), but prevalence in ischemic cardiomyopathy (ICM) and association with remodeling are unknown. The population comprised patients with systolic dysfunction [LV ejection fraction (LVEF ≤ 40 %)]. CMR was used to identify MW-LGE, conventionally defined as fibrosis of the mid-myocardial or epicardial aspect of the LV septum. 285 patients were studied. MW-LGE was present in 12 %, and was tenfold more common with NICM (32 %) versus ICM (3 %, p < 0.001). However, owing to higher prevalence of ICM, 15 % of patients with MW-LGE had ICM. LV wall stress was higher (p = 0.02) among patients with, versus those without, MW-LGE despite similar systolic blood pressure (p = 0.24). In multivariate analysis, MW-LGE was associated with CMR-quantified LV end-diastolic volume (p = 0.03) independent of LVEF and mass. Incorporation of clinical and imaging variables demonstrated MW-LGE to be associated with higher LV end-diastolic volume (OR 1.13, CI 1.004-1.27 per 10 ml/m(2), p = 0.04) after controlling for presence of NICM (OR 16.0, CI 5.8-44.1, p < 0.001). While more common in NICM, MW-LGE can occur in ICM and is a marker of LV chamber dilation irrespective of cardiomyopathic etiology.

P wave area for quantitative electrocardiographic assessment of left atrial remodeling.

BACKGROUND: Left atrial (LA) dilation provides a substrate for mitral regurgitation (MR) and atrial arrhythmias. ECG can screen for LA dilation but standard approaches do not assess LA geometry as a continuum, as does non-invasive imaging. This study tested ECG-quantified P wave area as an index of LA geometry. METHODS AND RESULTS: 342 patients with CAD underwent ECG and CMR within 7 (0.1±1.4) days. LA area on CMR correlated best with P wave area in ECG lead V1 (r = 0.42, p<0.001), with lesser correlations for P wave amplitude and duration. P wave area increased stepwise in relation to CMR-evidenced MR severity (p<0.001), with similar results for MR on echocardiography (performed in 86% of patients). Pulmonary arterial (PA) pressure on echo was increased by 50% among patients in the highest (45±14 mmHg) vs. the lowest (31±9 mmHg) P wave area quartile of the population. In multivariate regression, CMR and echo-specific models demonstrated P wave area to be independently associated with LA size after controlling for MR, as well as echo-evidenced PA pressure. Clinical follow-up (mean 2.4±1.9 years) demonstrated ECG and CMR to yield similar results for stratification of arrhythmic risk, with a 2.6-fold increase in risk for atrial fibrillation/flutter among patients in the top P wave area quartile of the population (CI 1.1-5.9, p = 0.02), and a 3.2-fold increase among patients in the top LA area quartile (CI 1.4-7.0, p = 0.005). CONCLUSIONS: ECG-quantified P wave area provides an index of LA remodeling that parallels CMR-evidenced LA chamber geometry, and provides similar predictive value for stratification of atrial arrhythmic risk.