Mitral Valve Transcatheter Edge-to-Edge Repair Volumes and Trends.

Background: Despite an association between operator volumes and procedural success, there remains an incomplete understanding of the contemporary utilization and procedural volumes for mitral valve transcatheter edge-to-edge repair (MTEER). We aimed to identify annual operator procedural volumes, temporal trends, and geographic variability for MTEER among Medicare patients in the United States (US). Methods: We queried the National Medicare Provider Utilization and Payment Database for a CPT code (33418) specific for MitraClip device from 2015 through 2019. We analyzed annual operator procedural volumes and incidence and identified longitudinal and geographic trends in MTEER utilization. Results: From 2015 through 2019, a total of 27,034 MTEER procedures were performed among Medicare patients in the US. The nationwide incidence increased from 6.2 per 100,000 patients in 2015 to 23.8 per 100,000 patients in 2019, a 283% increase over the study period (Ptrend < 0.001). The incidence of MTEER by state varied by nearly 900% (range 5.5 to 54.9 per 100,000 person-years). In 2019, the mean annual MTEER operator annual volume was 9.1 MTEER procedures and had grown from 6.2 per year in 2015. Conclusions: In this nationwide study of Medicare beneficiaries in the United States, we identified a significant and sustained increase in the utilization of MTEER devices and operators and growth in annual procedural volumes from 2015 through 2019 with considerable variability in utilization by state. Further studies are needed to understand the clinical impact of variability in utilization and the optimal procedural volumes to ensure high efficacy outcomes and maintain critical access to MTEER therapies.

Bioprosthetic valve oversizing is associated with increased risk of valve thrombosis following TAVR.

BACKGROUND: Hypoattenuating leaflet thickening (HALT), the radiographic manifestation of transcatheter heart valve thrombosis, is commonly identified following transcatheter aortic valve replacement (TAVR) and associated with increased risk of stroke and structural valve deterioration. While anticoagulation effectively resolves HALT, routine use remains controversial. We aimed to identify hemodynamic, anatomic, and comorbid predictors of HALT. METHODS: We evaluated consecutive patients with severe aortic stenosis who underwent TAVR with Edwards SAPIEN 3 bioprosthesis at a single center between June 1, 2018 and October 30, 2019. Patients on anticoagulation and those receiving valve-in-valve were excluded. Clinically driven computed tomography (CT) imaging was performed to assess for HALT at the discretion of the treating valve team. RESULTS: A total of 78 patients with a mean age of 78 ± 10 years and STS risk score 5.5 ± 3.3% were analyzed. HALT was identified in 11 (14.1%) patients. Compared to controls, those with HALT had smaller annular areas, 435 ± 57 mm2 vs. 489 ± 79 mm2 (p = .032), but received comparable size valves. In multivariate regression, valve oversizing by more than 20% was associated with increased risk of HALT, OR 23.5, 95% CI 2.5-223, (p = .006). After initiation of anticoagulation, patients with HALT had similar rates of stroke, major bleeding, and all-cause mortality out to an average of 243 days. CONCLUSIONS: In this pragmatic study of patients undergoing TAVR with SAPIEN 3 valves, we report the novel finding that oversizing by more than 20% was independently associated with increased risk of HALT. These findings warrant confirmation in larger and prospective trials.

Proinflammatory endothelial activation detected by molecular imaging in obese nonhuman primates coincides with onset of insulin resistance and progressively increases with duration of insulin resistance.

BACKGROUND: Inflammation and insulin resistance (IR) are associated processes that potentiate risk for cardiovascular disease in obesity. The temporal relation between IR and inflammation is not completely characterized. We hypothesized that endothelial cell adhesion molecule expression in large arteries is an early event that coincides with diet-induced obesity and IR in primates. METHODS AND RESULTS: Ten adult male rhesus macaques were studied at baseline and every 4 to 6 months on a high-fat diet for 2 years. Truncal fat, carotid intima-media thickness, plasma inflammatory biomarkers, and carotid P-selectin and vascular cell adhesion molecule-1 expression by contrast-enhanced ultrasound molecular imaging were assessed. Intravenous glucose tolerance test was performed at baseline and at 4 and 18 months. A high-fat diet produced a rapid increase (P<0.01) in weight, truncal fat, and degree of IR indicated by the insulin area under the curve and glucose disappearance rate on intravenous glucose tolerance test, all of which worsened minimally thereafter. Molecular imaging detected a progressive increase in endothelial cell adhesion molecule expression over time (5- to 7-fold greater than control agent signal at 2 years; P<0.01). Changes in intima-media thickness were not detected until 2 years and, although there was a trend toward an increase in plasma markers of inflammation (monocyte chemotactic protein-1, C-reactive protein), the pattern of increase varied considerably over time. CONCLUSIONS: In primates with diet-induced obesity, endothelial inflammatory activation is an early event that occurs coincident with the development of IR and long before any measurable change in carotid intima-media thickness. Endothelial activation is related more to the duration rather than to the severity of IR and is not mirrored by changes in plasma biomarkers.

Imaging of the Mitral Valve.

Echocardiographic imaging is the foundation for the evaluation of mitral valve dysfunction. Both transthoracic and transesophageal echocardiography provide insight into the anatomy, pathology, and classification mitral valve dysfunction. Echocardiography also provides a multi-parametric approach with semi-quantitative and quantitative parameters to assess the severity of mitral regurgitation and mitral stenosis. Transesophageal imaging is essential in the assessment of patients considered for surgical or transcatheter interventional strategies to treat mitral valve dysfunction. Cardiac computed tomography (CT) and cardiac MRI are useful adjunctive imaging techniques in mitral valve disease with CT providing detailed procedural specificity and MRI providing detailed ventricular and regurgitant flow analysis.

Mortality Associated With Proportionality of Secondary Mitral Regurgitation After Transcatheter Mitral Valve Repair: North American Mitraclip for Functional Mitral Regurgitation Registry.

The association, if any, between the effective regurgitant orifice area (EROA) to left ventricular end-diastolic volume (LVEDV) ratio and 1-year mortality is controversial in patients who undergo mitral transcatheter edge-to-edge repair (m-TEER) with the MitraClip system (Abbott Vascular, Santa Clara, CA). This study's objective was to determine the association between EROA/LVEDV and 1-year mortality in patients who undergo m-TEER with MitraClip. In patients with severe secondary (functional) mitral regurgitation (MR), we analyzed registry data from 11 centers using generalized linear models with the generalized estimating equations approach. We studied 525 patients with secondary MR who underwent m-TEER. Most patients were male (63%) and were New York Heart Association class III (61%) or IV (21%). Mitral regurgitation was caused by ischemic cardiomyopathy in 51% of patients. EROA/LVEDV values varied widely, with median = 0.19 mm2/ml, interquartile range [0.12,0.28] mm2/ml, and 187 patients (36%) had values <0.15 mm2/ml. Postprocedural mitral regurgitation severity was substantially alleviated, being 1+ or less in 74%, 2+ in 20%, 3+ in 4%, and 4+ in 2%; 1-year mortality was 22%. After adjustment for confounders, the logarithmic transformation (Ln) of EROA/LVEDV was associated with 1-year mortality (odds ratio 0.600, 95% confidence interval 0.386 to 0.933, p = 0.023). A higher Society of Thoracic Surgeons risk score was also associated with increased mortality. In conclusion, lower values of Ln(EROA/LVEDV) were associated with increased 1-year mortality in this multicenter registry. The slope of the association is steep at low values but gradually flattens as Ln(EROA/LVEDV) increases.

Structural Heart Imaging Using 3-Dimensional Intracardiac Echocardiography: JACC Cardiovascular Imaging Position Statement.

3-dimensional (3D) intracardiac echocardiography (ICE) is emerging as a promising complement and potential alternative to transesophageal echocardiography for imaging guidance in structural heart interventions. To establish standardized practices, our multidisciplinary expert position statement serves as a comprehensive guide for the appropriate indications and utilization of 3D-ICE in various structural heart procedures. The paper covers essential aspects such as the fundamentals of 3D-ICE imaging, basic views, and workflow recommendations specifically tailored for ICE-guided structural heart procedures, such as transeptal puncture, device closure of intracardiac structures, and transcatheter mitral and tricuspid valve interventions. Current challenges, future directions, and training requirements to ensure operator proficiency are also discussed, thereby promoting the safety and efficacy of this innovative imaging modality to support expanding its future clinical applications.

Echocardiographic Outcomes With Transcatheter Edge-to-Edge Repair for Degenerative Mitral Regurgitation in Prohibitive Surgical Risk Patients.

BACKGROUND: The CLASP IID randomized trial (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial) demonstrated the safety and effectiveness of the PASCAL system for mitral transcatheter edge-to-edge repair (M-TEER) in patients at prohibitive surgical risk with significant symptomatic degenerative mitral regurgitation (DMR). OBJECTIVES: This study describes the echocardiographic methods and outcomes from the CLASP IID trial and analyzes baseline variables associated with residual mitral regurgitation (MR) ≤1+. METHODS: An independent echocardiographic core laboratory assessed echocardiographic parameters based on American Society of Echocardiography guidelines focusing on MR mechanism, severity, and feasibility of M-TEER. Factors associated with residual MR ≤1+ were identified using logistic regression. RESULTS: In 180 randomized patients, baseline echocardiographic parameters were well matched between the PASCAL (n = 117) and MitraClip (n = 63) groups, with flail leaflets present in 79.2% of patients. Baseline MR was 4+ in 76.4% and 3+ in 23.6% of patients. All patients achieved MR ≤2+ at discharge. The proportion of patients with MR ≤1+ was similar in both groups at discharge but diverged at 6 months, favoring PASCAL (83.7% vs 71.2%). Overall, patients with a smaller flail gap were significantly more likely to achieve MR ≤1+ at discharge (adjusted OR: 0.70; 95% CI: 0.50-0.99). Patients treated with PASCAL and those with a smaller flail gap were significantly more likely to sustain MR ≤1+ to 6 months (adjusted OR: 2.72 and 0.76; 95% CI: 1.08-6.89 and 0.60-0.98, respectively). CONCLUSIONS: The study used DMR-specific echocardiographic methodology for M-TEER reflecting current guidelines and advances in 3-dimensional echocardiography. Treatment with PASCAL and a smaller flail gap were significant factors in sustaining MR ≤1+ to 6 months. Results demonstrate that MR ≤1+ is an achievable benchmark for successful M-TEER. (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial [CLASP IID]; NCT03706833).

Intermediate-Term Outcomes Following Transcatheter Aortic Valve Implantation in Patients with a History of Chest Radiation Therapy: A Propensity Score Matched Analysis.

Chest radiation therapy (XRT) has been associated with a higher rate of mortality following surgical aortic valve replacement. We performed a single-center retrospective analysis of patients with severe AS who underwent TAVI from January 1 2012 to July 31 2020 comparing patients with and without XRT. A total of 915 patients met inclusion criteria, with a total of 50 patients found to have a history of XRT. At a mean follow-up of 2.4 years, unadjusted and propensity score matching analysis demonstrated no differences in mortality, heart failure or bleeding-related hospitalization, overall stroke, and 30-day pacemaker implantation in patients with and without XRT.

Clinical Predictors of Mortality and Heart Failure Hospitalization in Patients With Severe Tricuspid Regurgitation.

Background: There is an incomplete understanding of the predictors of morbidity and mortality in patients with severe tricuspid regurgitation (TR). This study sought to identify key risk factors for all-cause mortality and heart failure (HF) hospitalization among patients with severe TR. Methods: Patients with severe TR were identified from 2 centers, Oregon Health & Science University and Abrazo Health, from January 01, 2016 to December 31, 2018. Patients with any concomitant severe valvular diseases or prior valvular intervention were excluded. Multivariable regression was utilized to identify demographic, clinical, and echocardiographic variables independently associated with all-cause mortality or HF hospitalization. Results: 435 patients with severe TR were followed for a median of 2.8 years. The mean age of the population was 66.9 ± 18.5 years and 58% were female. All-cause mortality was identified in 20.5% of the population. Of the cohort, 35.4% of patients were hospitalized for HF. Isolated tricuspid valve intervention was performed in 2.5% of patients. Independent predictors of all-cause mortality included history of solid tumor (odds ratio [OR] 6.6, 95% confidence interval [CI] 2.1-19.1, p = 0.001), history of peripheral artery disease (OR 3.5, 95% CI 1.2-9.4, p = 0.013), and elevated international normalized ratio in the absence of anticoagulation (OR 1.9, 95% CI 1.2-3.2, p = 0.008). Predictors of HF hospitalization included history of diabetes mellitus (OR 2.2, 95% CI 1.1-4.0, p = 0.014) and history of reduced left ventricular ejection fraction (OR 5.7, 95% CI 2.9-11.7, p < 0.0001). Conclusions: Severe untreated TR is associated with high mortality and frequent HF hospitalizations. Understanding predictors of these outcomes is important to identify patients who may benefit from early tricuspid valve intervention to help improve outcomes in this patient population.

Activity restriction, impaired capillary function, and the development of insulin resistance in lean primates.

Insulin produces capillary recruitment in skeletal muscle through a nitric oxide (NO)-dependent mechanism. Capillary recruitment is blunted in obese and diabetic subjects and contributes to impaired glucose uptake. This study's objective was to define whether inactivity, in the absence of obesity, leads to impaired capillary recruitment and contributes to insulin resistance (IR). A comprehensive metabolic and vascular assessment was performed on 19 adult male rhesus macaques (Macaca mulatta) after sedation with ketamine and during maintenance anesthesia with isoflurane. Thirteen normal-activity (NA) and six activity-restricted (AR) primates underwent contrast-enhanced ultrasound to determine skeletal muscle capillary blood volume (CBV) during an intravenous glucose tolerance test (IVGTT) and during contractile exercise. NO bioactivity was assessed by flow-mediated vasodilation. Although there were no differences in weight, basal glucose, basal insulin, or truncal fat, AR primates were insulin resistant compared with NA primates during an IVGTT (2,225 ± 734 vs. 5,171 ± 3,431 µg·ml⁻¹·min⁻¹, P < 0.05). Peak CBV was lower in AR compared with NA primates during IVGTT (0.06 ± 0.01 vs. 0.12 ± 0.02 ml/g, P < 0.01) and exercise (0.10 ± 0.02 vs. 0.20 ± 0.02 ml/g, P < 0.01), resulting in a lower peak skeletal muscle blood flow in both circumstances. The insulin-mediated changes in CBV correlated inversely with the degree of IR and directly with activity. Flow-mediated dilation was lower in the AR primates (4.6 ± 1.0 vs. 9.8 ± 2.3%, P = 0.01). Thus, activity restriction produces impaired skeletal muscle capillary recruitment during a carbohydrate challenge and contributes to IR in the absence of obesity. Reduced NO bioactivity may be a pathological link between inactivity and impaired capillary function.

Severe MR With Prior Alfieri Stitch Treated With Transcatheter Edge-to-Edge Repair and a Vascular Plug.

We present a case of a high-risk surgical patient with prior surgical Alfieri stitch and recurrent severe mitral regurgitation. In cases with suitable anatomy, mitral valve transcatheter edge-to-edge repair and vascular plug closure of a small regurgitant orifice can be used with excellent results. (Level of Difficulty: Advanced.).

Three-Dimensional Intracardiac Echocardiography for Tricuspid Transcatheter Edge-to-Edge Repair.

Patients with severe symptomatic tricuspid regurgitation face a significant dilemma in treatment options, as the yearly mortality with medical therapy and the surgical mortality for tricuspid repair or replacement are high. Transcatheter edge-to-edge repair (TEER) for the tricuspid valve is becoming a viable option in patients, although procedural success is dependent on high-quality imaging. While transesophageal echocardiography remains the standard for tricuspid TEER procedures, intracardiac echocardiography (ICE) with three-dimensional (3D) multiplanar reconstruction (MPR) has many theoretical and practical advantages. The aim of this article was to describe the in vitro wet lab-based imaging work done to facilitate the best approach to 3D MPR ICE imaging and the procedural experience gained with 3D MPR ICE in tricuspid TEER procedures with the PASCAL device.

30-Day Outcomes Following Transfemoral Transseptal Transcatheter Mitral Valve Replacement: Intrepid TMVR Early Feasibility Study Results.

OBJECTIVES: The aim of this study was to evaluate outcomes of transcatheter mitral valve replacement (TMVR) with transfemoral access in patients at prohibitive or high surgical risk. BACKGROUND: Prohibitive surgical risk may preclude mitral valve replacement surgery in some patients. The investigational Intrepid TMVR system has previously been evaluated using transapical access for delivery of a self-expanding bioprosthetic valve. METHODS: This prospective, multicenter, nonrandomized early feasibility study evaluated the safety and performance of the Intrepid valve using transfemoral access enabling transseptal delivery in patients with moderate to severe or severe symptomatic mitral regurgitation at high surgical risk. Candidacy was determined by heart teams, with approval by a central screening committee. Echocardiographic data were evaluated by an independent core laboratory. Clinical events were adjudicated by a clinical events committee. RESULTS: Fifteen patients were enrolled at 6 sites from February 2020 to May 2021. The median age was 80 years, and median Society of Thoracic Surgeons Predicted Risk of Mortality was 4.7%; 87% of patients were men, and 53% had undergone prior sternotomy. Fourteen implants were successful. One patient was converted to surgery during the index procedure. Patients stayed a median of 5 days postprocedure. There were 6 access site bleeds (40%) and 11 iatrogenic atrial septal defect closures (73%). At 30 days, there were no deaths, strokes, or reinterventions. All patients undergoing implantation had trace or no valvular or paravalvular mitral regurgitation, and the mean gradient was 4.7 mm Hg (IQR: 3.0-6.7 mm Hg). CONCLUSIONS: Thirty-day results from the Intrepid transfemoral TMVR early feasibility study demonstrate excellent valve function and no mortality or stroke. Additional patients and longer follow-up are needed to confirm these findings. ([The Early Feasibility Study of the Intrepid™ TMVR Transseptal System]; NCT02322840).

Molecular imaging with contrast enhanced ultrasound.

Noninvasive cardiovascular imaging techniques are well-established for studying cardiovascular anatomy and physiology. Over the past decade contrast enhanced imaging techniques have been developed that are also able to characterize the molecular constituents of cardiovascular disease. In this regard, microbubble- and ultrasound-based techniques have the ability to assess a broad range of molecular components of cardiovascular pathology such as inflammation, recent ischemia, atherosclerosis, acute transplant rejection, angiogenesis, and thrombosis. The advantages of ultrasound- and microbubble-based approach include the ability to assess multiple molecular disease markers without exposure to ionizing radiation or prolonged imaging protocols. This review highlights the development of microbubble-based molecular imaging, describes successful experimental conditions in which they have been studied, and postulates the importance of translating this technique into the clinical practice.

Late Type A Dissection After Transfemoral Aortic Valve Replacement.

An 87-year-old woman had residual moderate to severe aortic insufficiency following transcatheter aortic valve replacement. A year later, she developed extensive Stanford type A aortic dissection originating at the supra-annular aortic edge of the transcatheter aortic valve replacement nitinol frame. Dissection repair, frozen elephant trunk with exclusion of prior insufficiency while preserving the transcatheter aortic valve replacement valve was performed. (Level of Difficulty: Beginner.).

Clinical and Echocardiographic Predictors of Outcomes in Patients With Moderate (Mean Transvalvular Gradient 20 to 40 mm Hg) Aortic Stenosis.

Risk factors for adverse clinical outcomes in patients with moderate aortic stenosis are not well defined. Previous studies have suggested that certain patients with moderate AS may be at an increased risk of heart failure (HF) or death. All patients with moderate AS seen in our institution during the study period (6/1/2014 to 6/30/2017) with a minimum 1-year follow-up were included. Clinical and echocardiographic data were collected retrospectively. End points were defined as HF hospitalization, aortic valve replacement (AVR), or death. Kaplan-Meier and multivariable Cox proportional hazard models analyses were conducted using composite outcomes of (1) HF hospitalization or AVR and (2) HF hospitalization, AVR, or all-cause death. A total of 151 subjects met the inclusion criteria. The most significant risk factors associated with the composite outcomes were an ejection fraction (EF) <50% ((1) hazard ratio [HR]: 4.1; 95% confidence interval [CI]: 2.34, 7.12; (2) HR: 3.8; 95% CI: 2.2, 6.6), atrial fibrillation ((1) HR: 2.0; 95% CI: 1.2, 3.2; (2) HR: 2.1; 95% CI: 1.43, 3.2), left ventricular hypertrophy ((1) HR: 5.85; 95% CI: 2.0, 15.8; (2) HR: 3.2; 95% CI: 1.4, 7.4), aortic valve area ((1) HR: 0.3; 95% CI: 0.1, 0.6; (2) HR: 0.32; 95% CI: 0.1, 0.65), and abnormal right ventricular function ((1) HR: 4.3; 95% CI: 2.5, 7.5; (2) HR: 5.5; 95% CI: 3.0, 9.8). In conclusion, presence of reduced ejection fraction, atrial fibrillation, left ventricular hypertrophy, and abnormal right ventricular function are associated with an increased risk of HF hospitalization, AVR, and death in patients with moderate aortic stenosis.