Transcatheter Treatment Options for Functional Mitral Regurgitation: Which Device for Which Patients?

Mitral regurgitation is the most common valvular disease in the developed world, with approximately 24.2 million people being affected worldwide and a higher prevalence in older age groups. Surgical correction of degenerative mitral regurgitation is the standard of care and can restore cardiac function and provide a lasting result, especially when the mitral valve can be repaired. Secondary mitral regurgitation, or functional mitral regurgitation (FMR), describes atrial or ventricular factors leading to poor coaptation of an otherwise non-diseased valve. For FMR, traditional surgery has not produced the same level of benefit. Transcatheter mitral repair and replacement techniques that mimic surgical correction are under investigation. Transcatheter edge-to-edge repair is the only approved catheter-based therapy for FMR in the US. Here, the transcatheter treatment options for FMR are reviewed.

Overcoming prosthesis-patient mismatch with transcatheter aortic valve replacement.

For decades, surgeons have recognized the risk of prosthesis-patient mismatch (PPM) when treating aortic stenosis (AS) with surgical aortic valve replacement (SAVR). The concept of PPM-or placing a valve that is too small for the cardiac output requirements of the patient-has been associated with worse patient outcomes, including increased risk of death. Transcatheter aortic valve replacement (TAVR) has become the standard treatment for most patients with severe symptomatic AS and is associated with improved hemodynamics and lower risks of PPM. Larger surgical valves, stentless, and sutureless technology, and surgical aortic annulus enlargement (AAE) have been employed to avoid severe PPM. However, especially in the small aortic annulus (SAA), TAVR may provide a benefit. Understanding who is at risk for PPM requires preplanning, and cardiac-gated computed tomography (CT) imaging is the standard of care when considering TAVR. It should be standard for all patients with AS. Once SAA is identified, the risk of PPM can be calculated, and an informed decision made on whether to proceed with SAVR or TAVR. In the current TAVR era, younger patients are treated with TAVR driven by patient preference, but with little long-term data to support the practice. Selecting the best valve for the patient is a multifactorial decision often nuanced by anatomical considerations, hemodynamic and durability expectations, and decisions regarding lifetime management that may include placing a second valve. Although PPM may be only one of the factors to consider, the association with elevated mean gradients and worse outcomes certainly makes TAVR a good solution for many patients.

Impact of transcatheter heart valve type on outcomes of surgical explantation after failed transcatheter aortic valve replacement: the EXPLANT-TAVR international registry.

BACKGROUND: There are limited data on the impact of transcatheter heart valve (THV) type on the outcomes of surgical explantation after THV failure. AIMS: We sought to determine the outcomes of transcatheter aortic valve replacement (TAVR) explantation for failed balloon-expandable valves (BEV) versus self-expanding valves (SEV). METHODS: From November 2009 to February 2022, 401 patients across 42 centres in the EXPLANT-TAVR registry underwent TAVR explantation during a separate admission from the initial TAVR. Mechanically expandable valves (N=10, 2.5%) were excluded. The outcomes of TAVR explantation were compared for 202 (51.7%) failed BEV and 189 (48.3%) failed SEV. RESULTS: Among 391 patients analysed (mean age: 73.0±9.8 years; 33.8% female), the median time from index TAVR to TAVR explantation was 13.3 months (interquartile range 5.1-34.8), with no differences between groups. Indications for TAVR explantation included endocarditis (36.0% failed SEV vs 55.4% failed BEV; p<0.001), paravalvular leak (21.2% vs 11.9%; p=0.014), structural valve deterioration (30.2% vs 21.8%; p=0.065) and prosthesis-patient mismatch (8.5% vs 10.4%; p=0.61). The SEV group trended fewer urgent/emergency surgeries (52.0% vs 62.3%; p=0.057) and more root replacement (15.3% vs 7.4%; p=0.016). Concomitant cardiac procedures were performed in 57.8% of patients, including coronary artery bypass graft (24.8%), and mitral (38.9%) and tricuspid (14.6%) valve surgery, with no differences between groups. In-hospital, 30-day, and 1-year mortality and stroke rates were similar between groups (allp>0.05), with no differences in cumulative mortality at 3 years (log-rank p=0.95). On multivariable analysis, concomitant mitral surgery was an independent predictor of 1-year mortality after BEV explant (hazard ratio [HR] 2.00, 95% confidence interval [CI]: 1.07-3.72) and SEV explant (HR 2.00, 95% CI: 1.08-3.69). CONCLUSIONS: In the EXPLANT-TAVR global registry, BEV and SEV groups had different indications for surgical explantation, with more root replacements in SEV failure, but no differences in midterm mortality and morbidities. Further refinement of TAVR explantation techniques are important to improving outcomes.

Cardiac amyloidosis and aortic stenosis: a state-of-the-art review.

Cardiac amyloidosis is caused by the extracellular deposition of amyloid fibrils in the heart, involving not only the myocardium but also any cardiovascular structure. Indeed, this progressive infiltrative disease also involves the cardiac valves and, specifically, shows a high prevalence with aortic stenosis. Misfolded protein infiltration in the aortic valve leads to tissue damage resulting in the onset or worsening of valve stenosis. Transthyretin cardiac amyloidosis and aortic stenosis coexist in patients > 65 years in about 4-16% of cases, especially in those undergoing transcatheter aortic valve replacement. Diagnostic workup for cardiac amyloidosis in patients with aortic stenosis is based on a multi-parametric approach considering clinical assessment, electrocardiogram, haematologic tests, basic and advanced echocardiography, cardiac magnetic resonance, and technetium labelled cardiac scintigraphy like technetium-99 m (99mTc)-pyrophosphate, 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid, and 99mTc-hydroxymethylene diphosphonate. However, a biopsy is the traditional gold standard for diagnosis. The prognosis of patients with coexisting cardiac amyloidosis and aortic stenosis is still under evaluation. The combination of these two pathologies worsens the prognosis. Regarding treatment, mortality is reduced in patients with cardiac amyloidosis and severe aortic stenosis after undergoing transcatheter aortic valve replacement. Further studies are needed to confirm these findings and to understand whether the diagnosis of cardiac amyloidosis could affect therapeutic strategies. The aim of this review is to critically expose the current state-of-art regarding the association of cardiac amyloidosis with aortic stenosis, from pathophysiology to treatment.

Trends in surgical aortic valve replacement in pre- and post-transcatheter aortic valve replacement eras at a structural heart center.

Background: The advent of transcatheter aortic valve replacement (TAVR) has directly impacted the lifelong management of patients with aortic valve disease. The U.S. Food and Drug Administration has approved TAVR for all surgical risk: prohibitive (2011), high (2012), intermediate (2016), and low (2019). Since then, TAVR volumes are increasing and surgical aortic valve replacements (SAVR) are decreasing. This study sought to evaluate trends in isolated SAVR in the pre- and post-TAVR eras. Methods: From January 2000 to June 2020, 3,861 isolated SAVRs were performed at a single academic quaternary care institution which participated in the early trials of TAVR beginning in 2007. A formal structural heart center was established in 2012 when TAVR became commercially available. Patients were divided into the pre-TAVR era (2000-2011, n = 2,426) and post-TAVR era (2012-2020, n = 1,435). Data from the institutional Society of Thoracic Surgeons National Database was analyzed. Results: The median age was 66 years, similar between groups. The post-TAVR group had a statistically higher rate of diabetes, hypertension, dyslipidemia, heart failure, more reoperative SAVR, and lower STS Predicted Risk of Mortality (PROM) (2.0% vs. 2.5%, p < 0.0001). There were more urgent/emergent/salvage SAVRs (38% vs. 24%) and fewer elective SAVRs (63% vs. 76%), (p < 0.0001) in the post-TAVR group. More bioprosthetic valves were implanted in the post-TAVR group (85% vs. 74%, p < 0.0001). Larger aortic valves were implanted (25 vs. 23 mm, p < 0.0001) and more annular enlargements were performed (5.9% vs. 1.6%, p < 0.0001) in the post-TAVR era. Postoperatively, the post-TAVR group had less blood product transfusion (49% vs. 58%, p < 0.0001), renal failure (1.4% vs. 4.3%, p < 0.0001), pneumonia (2.3% vs. 3.8%, p = 0.01), shorter lengths of stay, and lower in-hospital mortality (1.5% vs. 3.3%, p = 0.0007). Conclusion: The approval of TAVR changed the landscape of aortic valve disease management. At a quaternary academic cardiac surgery center with a well-established structural heart program, patients undergoing isolated SAVR in the post-TAVR era had lower STS PROM, more implantation of bioprosthetic valves, utilization of larger valves, annular enlargement, and lower in-hospital mortality. Isolated SAVR continues to be performed in the TAVR era with excellent outcomes. SAVR remains an essential tool in the lifetime management of aortic valve disease.

Structural Valve Deterioration After Self-Expanding Transcatheter or Surgical Aortic Valve Implantation in Patients at Intermediate or High Risk.

Importance: The frequency and clinical importance of structural valve deterioration (SVD) in patients undergoing self-expanding transcatheter aortic valve implantation (TAVI) or surgery is poorly understood. Objective: To evaluate the 5-year incidence, clinical outcomes, and predictors of hemodynamic SVD in patients undergoing self-expanding TAVI or surgery. Design, Setting, and Participants: This post hoc analysis pooled data from the CoreValve US High Risk Pivotal (n = 615) and SURTAVI (n = 1484) randomized clinical trials (RCTs); it was supplemented by the CoreValve Extreme Risk Pivotal trial (n = 485) and CoreValve Continued Access Study (n = 2178). Patients with severe aortic valve stenosis deemed to be at intermediate or increased risk of 30-day surgical mortality were included. Data were collected from December 2010 to June 2016, and data were analyzed from December 2021 to October 2022. Interventions: Patients were randomized to self-expanding TAVI or surgery in the RCTs or underwent self-expanding TAVI for clinical indications in the nonrandomized studies. Main Outcomes and Measures: The primary end point was the incidence of SVD through 5 years (from the RCTs). Factors associated with SVD and its association with clinical outcomes were evaluated for the pooled RCT and non-RCT population. SVD was defined as (1) an increase in mean gradient of 10 mm Hg or greater from discharge or at 30 days to last echocardiography with a final mean gradient of 20 mm Hg or greater or (2) new-onset moderate or severe intraprosthetic aortic regurgitation or an increase of 1 grade or more. Results: Of 4762 included patients, 2605 (54.7%) were male, and the mean (SD) age was 82.1 (7.4) years. A total of 2099 RCT patients, including 1128 who received TAVI and 971 who received surgery, and 2663 non-RCT patients who received TAVI were included. The cumulative incidence of SVD treating death as a competing risk was lower in patients undergoing TAVI than surgery (TAVI, 2.20%; surgery, 4.38%; hazard ratio [HR], 0.46; 95% CI, 0.27-0.78; P = .004). This lower risk was most pronounced in patients with smaller annuli (23 mm diameter or smaller; TAVI, 1.32%; surgery, 5.84%; HR, 0.21; 95% CI, 0.06-0.73; P = .02). SVD was associated with increased 5-year all-cause mortality (HR, 2.03; 95% CI, 1.46-2.82; P < .001), cardiovascular mortality (HR, 1.86; 95% CI, 1.20-2.90; P = .006), and valve disease or worsening heart failure hospitalizations (HR, 2.17; 95% CI, 1.23-3.84; P = .008). Predictors of SVD were developed from multivariate analysis. Conclusions and Relevance: This study found a lower rate of SVD in patients undergoing self-expanding TAVI vs surgery at 5 years. Doppler echocardiography was a valuable tool to detect SVD, which was associated with worse clinical outcomes. Trial Registration: ClinicalTrials.gov Identifiers: NCT01240902, NCT01586910, and NCT01531374.

A Comparison of Thirty-Day Clinical and Echocardiographic Outcomes of Patients Undergoing Transcatheter vs. Surgical Aortic Valve Replacement for Native Aortic Insufficiency.

OBJECTIVES: We aim to compare in-hospital and 30-day outcomes of transcatheter aortic valve replacement (TAVR) versus surgical aortic valve replacement (SAVR) for native aortic insufficiency (AI). BACKGROUND: TAVR is increasingly used off-label in patients with AI deemed high risk for SAVR. There is a paucity of data comparing TAVR and SAVR with current commercially available TAVR devices. METHODS: A single-center, retrospective cohort study of patients undergoing TAVR or SAVR for native AI between 2014 and 2020 was performed. Data were obtained from the Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database, Transcatheter Valve Therapy (TVT) registry, and chart review. In-hospital and 30-day outcomes are reported. RESULTS: Of 125 total patients, 91 underwent SAVR and 34 underwent TAVR. The TAVR group had a higher STS predictive risk of mortality (PROM) (TAVR = 3.96 %, SAVR = 1.25 %, p < 0.0001). In the postoperative period, the SAVR group had higher rates of new-onset atrial fibrillation (20.9 % vs. 0 %, p < 0.001), while the TAVR group had higher rates of complete heart block requiring permanent pacemaker implantation (20.6 % vs. 2.2 %, p < 0.001). There was no difference in in-hospital or 30-day mortality, stroke, myocardial infarction, residual AI, or repeat valve intervention. CONCLUSIONS: Despite higher STS PROM and more comorbidities, patients who underwent TAVR for AI had similar in-hospital and 30-day outcomes as patients who underwent SAVR for AI. These results support TAVR in selected high-risk patients with AI, with the knowledge that pacemaker needs may be higher than patients undergoing SAVR.

A Practical Approach to Left Main Coronary Artery Disease: JACC State-of-the-Art Review.

The treatment of left main (LM) coronary artery disease (CAD) requires complex decision-making. Recent clinical practice guidelines provide clinicians with guidance; however, decisions regarding treatment for individual patients can still be difficult. The American College of Cardiology's Cardiac Surgery Team and Interventional Council joined together to develop a practical approach to the treatment of LM CAD, taking into account randomized clinical trial, meta-analyses, and clinical practice guidelines. The various presentations of LM CAD based on anatomy and physiology are presented. Recognizing the complexity of LM CAD, which rarely presents isolated and is often in combination with multivessel disease, a treatment algorithm with medical therapy alone or in conjunction with percutaneous coronary intervention or coronary artery bypass grafting is proposed. A heart team approach is recommended that accounts for clinical, procedural, operator, and institutional factors, and features shared decision-making that meets the needs and preferences of each patient and their specific clinical situation.

Evolving computed tomography angiography for aortic valve replacement: Optimizing transcatheter and surgical therapies.

Transcatheter aortic valve replacement (TAVR) has transformed the treatment of aortic stenosis and pre-procedure planning relies heavily on advanced imaging. Multidetector computed tomography angiography, the "TAVR CT," facilitates essential planning steps of measuring the aortic root for valve sizing and feasibility and assessment of potential access vessels, making it the guideline gold standard in preprocedural TAVR work up. This Impact of Advanced Imaging Techniques on Cardiac Surgery article will examine the development of TAVR CT, illustrate the current impact and utility, and highlight potential areas of future growth. Clinicians who keep informed of these changes and can become proficient with TAVR CT analyses will offer patients the most optimal results and fuel future therapeutic growth.