3-Year Outcomes of Balloon-Expandable Valves: 20-mm vs Larger Valves (≥23 mm).

BACKGROUND: A prior Society of Thoracic Surgeons/American College of Cardiology TVT (Transcatheter Valve Therapy) Registry-based analysis reported similar 1-year clinical outcomes with small (20-mm) vs large (≥23-mm) balloon-expandable valves (BEV). OBJECTIVES: The aim of this study was to describe mid-term 3-year clinical outcomes for small vs large BEV and the relationship between discharge echocardiographic mean gradient (MG) and different definitions of prothesis-patient mismatch (PPM) with clinical outcomes. METHODS: Using the TVT Registry with Centers for Medicare and Medicaid Services linkage, a propensity-matched analysis of patients receiving 20- vs ≥23-mm BEVs was performed. Spline curves and Kaplan-Meier plots with adjusted HRs determined the relationship between MG and 3-year mortality. RESULTS: In total, 316,091 patients were analyzed; after propensity matching, 8,100 pairs of each group were compared. The 20-mm BEV was associated with higher MGs compared with ≥23-mm BEVs (16.2 ± 7.2 mm Hg vs 11.8 ± 5.7 mm Hg; P < 0.0001). At 3 years, there was no difference in mortality between 20- and ≥23-mm BEVs (31.5% vs 32.5%, respectively; HR: 0.97; 95% CI: 0.90-1.05). Compared with an MG of 10 to 30 mm Hg, an MG <10 mm Hg (HR: 1.25; 95% CI:1.22-1.27) was associated with increased 3-year mortality. Measured severe PPM and predicted no PPM were associated with increased 3-year mortality (33.5% vs 32.9% vs 32.1%; P < 0.0001) and (33.5% vs 31.1% vs 30%; P < 0.0001), respectively. Low MG and severe measured PPM were associated with lower left ventricular ejection fraction (LVEF). CONCLUSIONS: Patients with small-prosthesis BEVs (20 mm) had identical 3-year survival as those with larger (≥23-mm) BEV valves. Severe measured PPM and low MG (<10 mm Hg), but not predicted severe PPM, were associated with lower LVEF and increased mortality, suggesting that LVEF is the culprit for worse outcomes.

Cerebral Embolic Protection Devices for Transcatheter Aortic Valve Replacement: Review of the Literature and Future Perspectives.

PURPOSE OF REVIEW: Transcatheter aortic valve replacement (TAVR) has been a revolutionary therapy in the treatment of aortic valve stenosis. The risk of stroke associated with TAVR has decreased significantly since its introduction; however, it remains a devastating complication when it does occur. RECENT FINDINGS: Many of the strokes associated with TAVR occur peri-procedurally and are thought to be due to embolic debris entering the cerebrovascular circulation. A number of different cerebral embolic protection devices (CEPD) have been developed and are in various stages of testing and use. The results from clinical trials evaluating the role for CEPD to reduce the risk of stroke have been mixed. As a result, their uptake has been very heterogeneous. This review provides a summary of the diverse CEPD devices available for use and outlines the clinical evidence available to date.

Sex differences in device-measured physical activity after transcatheter aortic valve replacement.

OBJECTIVE: Physical activity (PA) is an important clinical and quality of life outcome after transcatheter aortic valve replacement (TAVR). We examined the effect of TAVR on objectively measured PA in patients with cardiac implanted electronic devices (CIEDs). METHODS: Daily accelerometer data was obtained from CIEDs. Patients in the University of North Carolina Health System with continuous PA data at least 6 months before TAVR and 12 months after TAVR were included. Changes in activity pre- and post-TAVR were analyzed with linear mixed-effects models using a random intercept for each patient. An interaction term was included to determine differences in PA between men and women pre- and post-TAVR. RESULTS: Of the 306 patients with CIEDs who underwent TAVR, 24,655 patient-days of data from 46 patients, mean age of 82 years old, 44% of whom were female met inclusion criteria. A significant and sustained increase of 14.7% in daily PA was seen after TAVR [10.15 minutes per day, 95% confidence interval (CI) 8.75 to 11.56 P < .001] after adjusting for sex, obesity, race, history of depression, and Charlson Comorbidity Index. Effects were more prominent in women (18.57 [95% CI 16.36 to 20.79, P < .001] minute increase post-TAVR) compared to men (4.51 [95% CI 3.87 to 5.16] minute increase post-TAVR, P < .001). CONCLUSIONS: This study demonstrates PA increases after TAVR with effects more pronounced in women than men. Further, this study highlights the potential use of remote monitoring data for monitoring functional outcomes in device patients after a procedure.

Simulating Cardiac Fluid Dynamics in the Human Heart.

Cardiac fluid dynamics fundamentally involves interactions between complex blood flows and the structural deformations of the muscular heart walls and the thin, flexible valve leaflets. There has been longstanding scientific, engineering, and medical interest in creating mathematical models of the heart that capture, explain, and predict these fluid-structure interactions. However, existing computational models that account for interactions among the blood, the actively contracting myocardium, and the cardiac valves are limited in their abilities to predict valve performance, resolve fine-scale flow features, or use realistic descriptions of tissue biomechanics. Here we introduce and benchmark a comprehensive mathematical model of cardiac fluid dynamics in the human heart. A unique feature of our model is that it incorporates biomechanically detailed descriptions of all major cardiac structures that are calibrated using tensile tests of human tissue specimens to reflect the heart's microstructure. Further, it is the first fluid-structure interaction model of the heart that provides anatomically and physiologically detailed representations of all four cardiac valves. We demonstrate that this integrative model generates physiologic dynamics, including realistic pressure-volume loops that automatically capture isovolumetric contraction and relaxation, and predicts fine-scale flow features. None of these outputs are prescribed; instead, they emerge from interactions within our comprehensive description of cardiac physiology. Such models can serve as tools for predicting the impacts of medical devices or clinical interventions. They also can serve as platforms for mechanistic studies of cardiac pathophysiology and dysfunction, including congenital defects, cardiomyopathies, and heart failure, that are difficult or impossible to perform in patients.

A model of fluid-structure and biochemical interactions for applications to subclinical leaflet thrombosis.

Subclinical leaflet thrombosis (SLT) is a potentially serious complication of aortic valve replacement with a bioprosthetic valve in which blood clots form on the replacement valve. SLT is associated with increased risk of transient ischemic attacks and strokes and can progress to clinical leaflet thrombosis. SLT following aortic valve replacement also may be related to subsequent structural valve deterioration, which can impair the durability of the valve replacement. Because of the difficulty in clinical imaging of SLT, models are needed to determine the mechanisms of SLT and could eventually predict which patients will develop SLT. To this end, we develop methods to simulate leaflet thrombosis that combine fluid-structure interaction and a simplified thrombosis model that allows for deposition along the moving leaflets. Additionally, this model can be adapted to model deposition or absorption along other moving boundaries. We present convergence results and quantify the model's ability to realize changes in valve opening and pressures. These new approaches are an important advancement in our tools for modeling thrombosis because they incorporate both adhesion to the surface of the moving leaflets and feedback to the fluid-structure interaction.

Successful aortic valve replacement by overexpanding a SAPIEN transcatheter heart valve for a large aortic annulus (>900†mm2): a case report.

Background: There are limited commercial valve sizes available for transcatheter aortic valve implantation (TAVI). This makes it challenging or even prohibitive to perform TAVI on large aortic annuli. Case summary: A 78-year-old male with known low-flow, low-gradient severe aortic stenosis presented with progressive dyspnoea, chest pressure, and decompensated heart failure. Successful off-label TAVI was performed for tricuspid aortic valve stenosis with an aortic annulus of >900 mm2. An Edwards S3 29 mm valve was overexpanded with an extra 7 mL of volume at valve deployment. No complications occurred, and only trivial paravalvular leak was seen following implantation. The patient died from a non-cardiovascular cause 8 months following the procedure. Discussion: Patients that require aortic valve replacement with prohibitive surgical risk and have very large aortic valve annuli pose significant technical challenges. This case shows the feasibility of TAVI by overexpanding an Edwards S3 valve.

Contemporary Trends in Acute Myocardial Infarction in the American Indian/Alaska Native U.S. Population, 2000 to 2018.

Coronary heart disease is disproportionately prevalent in the American Indian/Alaska Native (AI/AN) population. As care for acute myocardial infarction (AMI) continues to advance, equitable distribution and access for the AI/AN population is essential. Primary AMI hospitalizations for adults ≥18 years of age were identified from the Healthcare Cost and Utilization Project National Inpatient Sample from 2000 to 2018. Related co-morbidities, procedures of interest, and in-hospital mortality were also identified. These rates were stratified by race then trended over years using Poisson regression. Overall, 9,904,714 weighted hospitalizations for primary AMI were identified. From 2000 to 2018, AI/AN adults had relatively high rates of primary AMI hospitalization, second only to non-Hispanic (NH) White adults. The AMI rate increased from 14.0/1,000 to 16.1/1,000 among AI/AN adults, remaining higher than NH Black adults (12.1/1,000 to 13.0/1,000) and Hispanic adults (10.3/1,000 and 12.7/1,000) and becoming increasingly closer to NH White adults (25.1/1,000 to 20.0/1,000) (p <0.001 for each). AI/AN adults presented 5 years earlier than their NH White counterparts (64 vs 69 years old; p <0.001). In-hospital mortality was approximately 5% for all race categories and decreased in all groups but decreased at a much greater rate for NH White, NH Black and Hispanic adults (0.2% per year) compared with AI/AN adults (0.08% per year; p <0.001 for each comparison). Rates of coronary angiography and percutaneous coronary intervention increased in all groups, but coronary artery bypass graft utilization increased only in AI/AN adults (from 7% to 10%, p <0.001). In conclusion, from 2000 to 2018, AI/AN adults had a high rate of AMI hospitalizations (second only to NH White adults) that increased significantly over time. AI/AN adults were 5 years younger than their NH White counterparts at index AMI hospitalization. Care during these hospitalizations was similar among all racial groups, and in-hospital mortality decreased for all groups, albeit to a lesser degree among AI/AN adults. This study highlights the need for improved access to outpatient primary AMI prevention in the AI/AN population.

Epidemiology and Outcomes of Aortic Stenosis in Acute Decompensated Heart Failure: The ARIC Study.

BACKGROUND: Few studies characterize the epidemiology and outcomes of aortic stenosis (AS) in acute decompensated heart failure (ADHF). This study investigates the significance of AS in contemporary patients who have experienced an ADHF hospitalization. METHODS: The ARIC study (Atherosclerosis Risk in Communities) surveilled ADHF hospitalizations for residents ≥55 years of age in 4 US communities. ADHF cases were stratified by left ventricular ejection fraction (LVEF). Demographic differences in AS burden and the association of varying AS severities with mortality were estimated using multivariable logistic regression. RESULTS: From 2005 through 2014, there were 3597 (weighted n=16 692) ADHF hospitalizations of which 48.6% had an LVEF <50% and 51.4% an LVEF ≥50%. AS prevalence was 12.1% and 18.7% in those with an LVEF <50% and ≥50%, respectively. AS was less likely in Black than White patients regardless of LVEF: LVEF <50% (odds ratio [OR], 0.34 [95% CI, 0.28-0.42]); LVEF ≥50% (OR, 0.51 [95% CI, 0.44-0.59]). Higher AS severity was independently associated with 1-year mortality in both LVEF subgroups: LVEF <50% (OR, 1.16 [95% CI, 1.04-1.28]); LVEF ≥50% (OR, 1.40 [95% CI, 1.28-1.54]). Sensitivity analyses excluding severe AS patients detected that mild/moderate AS was independently associated with 1-year mortality in both LVEF subgroups: LVEF <50% (OR, 1.23 [95% CI, 1.02-1.47]); LVEF ≥50% (OR, 1.31 [95% CI, 1.14-1.51]). CONCLUSIONS: Among patients who have experienced an ADHF hospitalization, AS is prevalent and portends poor mortality outcomes. Notably, mild/moderate AS is independently associated with 1-year mortality in this high-risk population.

Patient-Specific Immersed Finite Element-Difference Model of Transcatheter Aortic Valve Replacement.

Transcatheter aortic valve replacement (TAVR) first received FDA approval for high-risk surgical patients in 2011 and has been approved for low-risk surgical patients since 2019. It is now the most common type of aortic valve replacement, and its use continues to accelerate. Computer modeling and simulation (CM&S) is a tool to aid in TAVR device design, regulatory approval, and indication in patient-specific care. This study introduces a computational fluid-structure interaction (FSI) model of TAVR with Medtronic's CoreValve Evolut R device using the immersed finite element-difference (IFED) method. We perform dynamic simulations of crimping and deployment of the Evolut R, as well as device behavior across the cardiac cycle in a patient-specific aortic root anatomy reconstructed from computed tomography (CT) image data. These IFED simulations, which incorporate biomechanics models fit to experimental tensile test data, automatically capture the contact within the device and between the self-expanding stent and native anatomy. Further, we apply realistic driving and loading conditions based on clinical measurements of human ventricular and aortic pressures and flow rates to demonstrate that our Evolut R model supports a physiological diastolic pressure load and provides informative clinical performance predictions.

Suprasternal transcatheter aortic valve replacement: Modified trocar-free technique.

BACKGROUND AND AIM OF STUDY: Transcatheter aortic valve replacement is established as the standard treatment for severe aortic stenosis. Many approaches have been described, including the suprasternal technique, an alternative for patients with unsuitable femoral arteries. We now describe a trocar-free technique for the Suprasternal approach. METHODS AND RESULTS: Under endotracheal anesthesia, an incision is made above the manubrium and dissection is carried down to the innominate artery with adequate exposure for cannulation. Access site is closed with purse-string suture. The Suprasternal approach has relatively few contraindications. CONCLUSION: Our trocar-free technique is a safe and easily reproducible technique for TAVRs in patients with poor femoral access.

Rule-based definition of muscle bundles in patient-specific models of the left atrium.

Atrial fibrillation (AF) is the most common arrhythmia encountered clinically, and as the population ages, its prevalence is increasing. Although the CHA2DS2- VASc score is the most used risk-stratification system for stroke risk in AF, it lacks personalization. Patient-specific computer models of the atria can facilitate personalized risk assessment and treatment planning. However, a challenge faced in creating such models is the complexity of the atrial muscle arrangement and its influence on the atrial fiber architecture. This work proposes a semi-automated rule-based algorithm to generate the local fiber orientation in the left atrium (LA). We use the solutions of several harmonic equations to decompose the LA anatomy into subregions. Solution gradients define a two-layer fiber field in each subregion. The robustness of our approach is demonstrated by recreating the fiber orientation on nine models of the LA obtained from AF patients who underwent WATCHMAN device implantation. This cohort of patients encompasses a variety of morphology variants of the left atrium, both in terms of the left atrial appendages (LAAs) and the number of pulmonary veins (PVs). We test the fiber construction algorithm by performing electrophysiology (EP) simulations. Furthermore, this study is the first to compare its results with other rule-based algorithms for the LA fiber architecture definition available in the literature. This analysis suggests that a multi-layer fiber architecture is important to capture complex electrical activation patterns. A notable advantage of our approach is the ability to reconstruct the main LA fiber bundles in a variety of morphologies while solving for a small number of harmonic fields, leading to a comparatively straightforward and reproducible approach.

Trends in Percutaneous Balloon Mitral Valvuloplasty Complications for Mitral Stenosis in the United States (the National Inpatient Sample [2008 to 2018]).

The epidemiology of mitral stenosis (MS) continues to evolve in the United States. Although the incidence of rheumatic MS has decreased in high-income countries, there is a paucity of data surrounding trends in percutaneous balloon mitral valvuloplasty (PBMV), the current first-line management strategy. This study aimed to identify contemporary trends in PBMV in the United States. Hospitalizations for adults (≥18 years) with MS who underwent PBMV were identified from the National Inpatient Sample from 2008 to 2018. Baseline co-morbidities and outcomes over the study period were determined using Poisson regression. There were 3,980 weighted PBMV cases, 70% of which were women. PBMV hospitalizations decreased from 603 in 2008 to 210 in 2018 (p <0.001). From 2008 to 2018, the age at hospitalization was unchanged in both female and male patients. In contrast, the Charlson Co-morbidity Index increased in both. Baseline heart failure (39% to 64%), hypertension (38% to 43%), and diabetes mellitus (17% to 26%) all substantially increased over the study period. In-hospital mortality occurred in 2% of female and 5% of male patients and was unchanged from 2008 to 2018. Vascular complications (12%) and acute kidney injury (10%) were the most frequent postprocedural complications during the 11-year study period. A composite of mortality or any postprocedural complication did not vary by gender (odds ratio 1.23, 95% confidence interval 0.88 to 1.72). In conclusion, the use of PBMV significantly decreased from 2008 to 2018, and patients with MS who underwent PBMV over this period had an increased burden of co-morbidities, elevated postprocedural complication rate, and no change in in-hospital mortality.

Temporal Trends in Internal vs. External Referrals for TAVR in a Large Academic Center: Patients Characteristics and Outcomes.

Background: Since transcatheter aortic valve replacement (TAVR) first became approved for inoperable patients followed by high, intermediate-, and low-risk patients, referrals to TAVR centers have rapidly increased. The purpose of this study was to investigate referral patterns to a large academic TAVR center in the state of North Carolina and evaluate differences between externally and internally referred patients. Methods: Data for all patients who underwent TAVR at our institution between November 2014 and March 2020 were pulled from the Transcatheter Valve Therapy Registry. The electronic medical record was used to determine the referral source. The descriptive statistical analysis was performed using Excel (Microsoft, Redmond, Washington). Results: 491 patients underwent TAVR at our institution between November 2014 and March 2020. Half of the patients were referred by a cardiologist within the same health system (N = 250, 50.9%). Other referral sources included a cardiologist external to the health system (N = 210, N = 42.8%) and a surgeon or proceduralist (such as urologist, surgeon, or gastroenterologist) during the workup for another procedure (N = 26, 5.3%). Over time, there was a trend toward an increasing proportion of patients referred by a cardiologist external to our system, but this trend did not reach statistical significance (20.0% in 2014, 29.2% in 2015, 30.7% in 2016, 53.0% in 2017, 36% in 2018, 48.4% in 2019, and 56.8% in 2020, p=0.06 using the Mann-Kendall trend test). Externally referred patients were less likely to have private insurance and were more likely to have a reduced ejection fraction and had a higher mean gradient across the valve. Postprocedure, externally referred patients were more likely to have the procedure under moderate sedation and less likely to be discharged home. Conclusions: This study presents the referral pattern to a large TAVR center in North Carolina. Over time, there was an increase in external referrals suggesting that TAVR is increasingly adopted as an important component of the management of aortic valve stenosis. Internally and externally referred patients have differences in baseline demographic and clinical characteristics which may have an impact on clinical outcomes.

Early outcomes of the suprasternal transcatheter aortic valve replacement technique.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is now an established treatment option for patients with severe aortic stenosis. The most utilized approach remains transfemoral. In patients with difficult femoral access a variety of alternate approaches have been used. Recently, suprasternal access has emerged as a viable alternate approach in patients with very complex vascular access. We describe our 30-day outcomes of patients who underwent suprasternal transcatheter aortic valve replacement (suprasternal [SS]-TAVR), which constitutes the largest single-center cohort to date. METHODS: From May 2016 to September 2021, 658 patients underwent TAVR at our institution. Of which 29 underwent SS-TAVR. We performed a retrospective analysis to evaluate early (30 days) outcomes of this procedure. Main outcomes evaluated included 30-day mortality, stroke and pacemaker rates, length of stay, readmission, and valvular function. RESULTS: All patients were alive 30 days after the procedure. The median hospital length-of-stay was 2 days. Two patients (6.9%) had a stroke on the contra-lateral side of access. Two patients (6.90%) had significant cardiac arrhythmias requiring pacemaker placement. In 30 days, one patient was readmitted (3.45%). CONCLUSIONS: Our data confirm the SS-TAVR as a feasible and safe alternative with comparable results to established approaches in patients who are unsuitable for femoral artery access and offers clinicians another access site in patients with very complex anatomy.

Five-year trends in cause-specific readmissions and cost burden of mitral transcatheter edge-to-edge repair.

OBJECTIVES: The study aimed to evaluate cost trends associated with mitral valve transcatheter edge-to-edge repair (TEER). BACKGROUND: TEER is a treatment option for patients at prohibitive surgical risk with moderate to severe mitral valve regurgitation and NYHA class III or IV symptoms. The 30-day costs and causes of readmission following TEER have not been well studied. METHODS: Patients undergoing mitral TEER in the United States from 2014 to 2018 were identified in the Nationwide Readmission Database. Patient characteristics, cause-specific readmission, and costs of the index hospitalization and readmissions were analyzed. Costs were trended over years using general linear regression. RESULTS: A total of 10,196 patients underwent mitral TEER during the study period. Thirty-day readmissions were stable over time at around 16%. The mean length of stay following TEER decreased from 7 days in 2014 to 5 days in 2018. There was a significant decline in the cost of the index hospitalization of $1311 per year, and a significant decline in the total 30-day cost of $1588 per year (p < 0.001). This was strictly due to a reduction in the cost of the index hospitalization without a change in readmission costs over time (p = 0.23). Infectious causes of readmissions significantly decreased while total cardiovascular readmissions, including heart failure, remained constant. CONCLUSION: The decreasing 30-day cost burden of TEER is primarily driven by the shorter index length of stay, as experience in TEER has grown and, length of stay has declined. However, cardiovascular readmissions, and consequently readmission costs, have remained steady.

The Relationship Between Atrial Fibrillation, Mitral Regurgitation, and Heart Failure Subtype: The ARIC Study.

BACKGROUND: Atrial fibrillation (AF) and mitral regurgitation (MR) are closely interrelated in the setting of heart failure (HF). Here we investigate the prevalence and prognostic significance of AF in patients with acute decompensated HF (ADHF) stratified by MR severity. METHODS AND RESULTS: The Atherosclerosis Risk in Communities Study investigated ADHF hospitalizations in residents greater than or equal to 55 years of age in 4 US communities. ADHF cases were stratified by MR severity (none/mild or moderate/severe) and HF subtype (HF with reduced [HFrEF] or preserved [HFpEF] ejection fraction). The odds of AF in patients with increasing MR severity was estimated using multivariable logistic regression, adjusting for age, race, sex, diabetes, hypertension, coronary artery disease, hemodialysis, stroke, and anemia. Cox regression models were used to assess the association of AF with 1-year mortality in patients with HFpEF and HFrEF, stratified by MR severity and adjusted as described, also adjusting for the year of hospitalization. From 2005 to 2014, there were 3,878 ADHF hospitalizations (17,931 weighted). AF was more likely in those with higher MR severity regardless of HF subtype; more so in HFpEF (odds ratio [OR] 1.38, 95% confidence interval [CI], 1.31-1.45) than in HFrEF (OR, 1.19, 95% CI, 1.13-1.25) (interaction P [by HF subtype] < .01). When stratified by HF type, association between AF and 1-year mortality was noted in patients with HFpEF (OR, 1.28, 95% CI 1.04-1.56) but not HFrEF (OR 0.96, 95% CI 0.79-1.16) (interaction by EF subtype, P = .02). CONCLUSIONS: In patients with ADHF, AF prevalence increased with MR severity and this effect was more pronounced in HFpEF compared with HFrEF. AF was associated with an increased 1-year mortality only in patients with HFpEF and concomitant moderate/severe MR. REGISTRATION: NCT00005131, https://clinicaltrials.gov/ct2/show/NCT00005131.

The selection of transcatheter heart valves in transcatheter aortic valve replacement.

Transcatheter heart valve technology has rapidly progressed since initial approval in the United States. There are currently two widely available transcatheter heart valve delivery systems approved in the US; however limited data exist on optimal device selection for various patient populations. This review explores the characteristics of currently approved transcatheter heart valve systems and scenarios where one valve system may be favored over others. We provide a simplified decision tree for selecting the optimal transcatheter valve system for specific patient-centered characteristics.

Propofol Versus Remifentanil Sedation for Transcatheter Aortic Valve Replacement: A Single Academic Center Experience.

OBJECTIVE: Comparison of remifentanil versus propofol for sedation during transcatheter aortic valve replacement (TAVR) procedures to analyze the risk of sedation-related hypoxemia and hypotension. Secondary outcomes included the rate of conversion to general anesthesia, procedure length, rate of intensive care unit (ICU) admission, ICU and hospital lengths of stay, and 30-day mortality. DESIGN: Retrospective cohort study. SETTING: A single tertiary teaching hospital. PARTICIPANTS: Two hundred fifty-nine patients who had propofol or remifentanil sedation for TAVR between March 2017 and March 2020. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: There were 130 patients (50.2%) in the propofol cohort and 129 patients (49.8%) in the remifentanil cohort. The primary outcomes were oxygen saturation nadir values and vasopressor infusion use. Remifentanil was associated with a lower oxygen saturation nadir, as compared to propofol (91.3% v . 95.4%, p < 0.001). Risk factors associated with hypoxemia (defined as <92%) were body mass index (p = 0.0004), obstructive sleep apnea (p = 0.004), and remifentanil maintenance (p < 0.001). Vasopressor infusion use was significantly higher with propofol (64.9% v . 8.5%, p < 0.001). Propofol maintenance and angiotensin-converting enzyme inhibitor/angiotensin II receptor-blocker use were the only variables identified as risk factors for vasopressor use (p < 0.001 and p = 0.009). CONCLUSIONS: For patients undergoing TAVR with conscious sedation, remifentanil was associated with more hypoxemia while propofol was associated with a higher rate of vasopressor use.

Evaluation and Management of Heart Block After Transcatheter Aortic Valve Replacement.

Transcatheter aortic valve replacement (TAVR) has developed substantially since its inception. Improvements in valve design, valve deployment technologies, preprocedural imaging and increased operator experience have led to a gradual decline in length of hospitalisation after TAVR. Despite these advances, the need for permanent pacemaker implantation for post-TAVR high-degree atrioventricular block (HAVB) has persisted and has well-established risk factors which can be used to identify patients who are at high risk and advise them accordingly. While most HAVB occurs within 48 hours of the procedure, there is a growing number of patients developing HAVB after initial hospitalisation for TAVR due to the trend for early discharge from hospital. Several observation and management strategies have been proposed. This article reviews major known risk factors for HAVB after TAVR, discusses trends in the timing of HAVB after TAVR and reviews some management strategies for observing transient HAVB after TAVR.