Transcatheter mitral valve therapies: State of the art.

Mitral regurgitation (MR) is one of the most prevalent valvular pathologies in the developed world. There continues to be a growing population of aging patients with MR who may be too high risk for surgical management. The rapid adoption and remarkable success of transcatheter aortic valve replacement (TAVR) generated enthusiasm for transcatheter mitral valve therapies; however, the complex anatomy and pathophysiology of the mitral valve confers several unique challenges for a fully percutaneous approach. Nevertheless, several devices are under development and in various phases of preclinical or clinical testing, both for transcatheter mitral valve replacement and repair. MitraClip (Abbott Vascular), which has received FDA approval, is the most established percutaneous repair strategy and has been performed in over 80,000 patients as of 2019. The following article serves as a review of the available and upcoming devices for the various etiologies of mitral valvular disease, as well as the unique challenges and potential complications of transcatheter mitral valve intervention.

Outcomes of transcatheter aortic valve replacement at teaching versus nonteaching hospitals.

INTRODUCTION: Prior studies have demonstrated that outcomes of invasive cardiac interventions may vary by hospital teaching status and volume. As transcatheter aortic valve replacement (TAVR) rapidly expands from teaching to nonteaching hospitals across the country, the clinical impact of hospital teaching status has not been clearly established. This study aimed to compare TAVR outcomes between nonteaching and teaching hospitals. METHODS: An observational study was conducted using the Nationwide Readmission Database (NRD). Patients undergoing TAVR from 2011 to 2018 were included. Data was analyzed using multivariable logistic regression to determine outcomes of 30-day mortality and readmission between nonteaching and teaching hospitals. RESULTS: A total of 235,321 patients underwent TAVR during the study period. Patients undergoing TAVR at teaching hospitals presented with a higher frequency of baseline comorbidities compared to nonteaching hospitals. Postprocedure complications such as myocardial infarction, arrhythmia, pneumonia, acute kidney injury, sepsis, stroke, and hemorrhage occurred more often at teaching centers (p < 0.001); translating to a higher rate of in-hospital mortality (2.27% vs. 1.99%, p = 0.006) and hospital cost ($48,300 vs. $44,900, p < 0.001) in teaching versus nonteaching hospitals. After adjusting for baseline characteristics and postoperative morbidity, in-hospital mortality (p = 0.095) and readmission rate (p = 0.420) on multivariable analysis were not statistically different between centers. CONCLUSION: With the evolution and expansion of TAVR to nonteaching centers, mortality, and readmission rates are not significantly different between nonteaching and teaching hospitals. Higher unadjusted in-hospital mortality at teaching centers suggest these centers more often treat high risk patients with associated increased complications.

ECMO and Impella Support Strategies as a Bridge to Surgical Repair of Post-Infarction Ventricular Septal Rupture.

Background and Objectives: Post-infarct ventricular septal rupture (PIVSR) continues to have significant morbidity and mortality, despite decreased prevalence. Impella and venoarterial extracorporeal membranous oxygenation (VA-ECMO) have been proposed as strategies to correct hemodynamic derangements and bridge patients to delayed operative repair when success rates are higher. This review places VA-ECMO and Impella support strategies in the context of bridging patients to successful PIVSR repair, with an additional case report of successful bridging with the Impella device. Materials and Methods: We report a case of PIVSR repair utilizing 14 days of Impella support. We additionally conducted a systematic review of contemporary literature to describe the application of VA-ECMO and Impella devices in the pre-operative period prior to surgical PIVSR correction. Expert commentary on the advantages and disadvantages of each of these techniques is provided. Results: We identified 19 studies with 72 patients undergoing VA-ECMO as a bridge to PIVSR repair and 6 studies with 11 patients utilizing an Impella device as a bridge to PIVSR repair. Overall, outcomes in both groups were better than expected from patients who were historically managed with medicine and balloon pump therapy, however there was a significant heterogeneity between studies. Impella provided for excellent left ventricular unloading, but did result in some concerns for reversal of shunting. VA-ECMO resulted in improved end-organ perfusion, but carried increased risks of device-related complications and requirement for additional ventricular unloading. Conclusions: Patients presenting with PIVSR in cardiogenic shock requiring a MCS bridge to definitive surgical repair continue to pose a challenge to the multidisciplinary cardiovascular team as the diverse presentation and management issues require individualized care plans. Both VA-ECMO and the Impella family of devices play a role in the contemporary management of PIVSR and offer distinct advantages and disadvantages depending on the clinical scenario. The limited case numbers reported demonstrate feasibility, safety, and recommendations for optimal management.

Hydrophilic polymer embolism induced acute transcatheter aortic valve thrombosis: a novel complication.

Hydrophilic polymer coated introducer sheaths and medical devices are widely used in interventional cardiology. Despite the potential procedural advantages that these provide, a risk of polymer embolization has been recently reported. We describe the first reported case of hydrophilic polymer induced acute transcatheter aortic valve thrombosis.

Magnetic navigation facilitates percutaneous coronary intervention for complex lesions.

BACKGROUND: We sought to determine the utility of a magnetic navigation system (MNS) in treating a variety of coronary artery lesions including those that could not be revascularized with standard percutaneous coronary intervention (PCI). MNS may add value in the treatment of tortuous arteries and bifurcation lesions; however its widespread adoption has lagged because of cost and a lack of clear advantage over conventional PCI. We performed a retrospective analysis to determine whether MNS improved procedural success for highly complex lesions. METHODS AND RESULTS: One hundred and forty-eight patients underwent treatment with MNS at Mayo Clinic, Rochester. Clinical data, angiographic and procedural characteristics, lesion crossing success and outcomes were reviewed. Overall 133 patients underwent successful revascularization with 87% (143) of 164 lesions crossed using MNS alone. Another six lesions required a combination of MNS and conventional devices resulting in overall success of 91% (149/164). Eighteen complex lesions had previously failed PCI and 12 (67%) were successfully treated with MNS. Success after failed PCI was higher (88%) when a frequent user operated MNS, but occasional users also noted incremental success (30%). Twenty-five chronic total occlusions were included amongst these 164 lesions, with observed antegrade MNS lesion crossing rates of 78% for regular and 14% for occasional users. CONCLUSIONS: MNS is a useful adjunct to performance of PCI. This specialized technology has a clear learning curve and can facilitate treatment of highly complex lesions.

Imaging of vulnerable plaques using near-infrared spectroscopy for risk stratification of atherosclerosis.

Although the prevalent approach in cardiology is largely "stenosis-centric," it has been long known that most acute coronary events are caused by apparently angiographically nonsignificant stenosis. This has led to a gradual paradigm shift from detection of significant stenosis to detection of lesion instability. A number of imaging modalities have been developed that help in this quest; however, none have been as promising as near-infrared spectroscopy used for detection of coronary plaque characteristics. In this article we discuss the various invasive imaging tools available to the interventional cardiologist, with special emphasis on near-infrared spectroscopy as a key emerging imaging technology.

Acute Coronary Syndrome After Transcatheter Aortic Valve Implantation (Results from Over 40,000 Patients).

Acute coronary syndrome (ACS) encompasses a broad category of presentations from unstable angina to ST-elevation myocardial infarctions. Most patients undergo coronary angiography upon presentation for diagnosis and treatment. However, the ACS management strategy after transcatheter aortic valve implantation (TAVI) may be complicated because of challenging coronary access. The National Readmission Database was reviewed to identify all patients who were readmitted with ACS within 90 days after TAVI between 2012 and 2018. Their outcomes were described between patients who were readmitted with ACS (ACS group) and without (non-ACS group). A total of 44,653 patients were readmitted within 90 days after TAVI. Among them, 1,416 patients (3.2%) were readmitted with ACS. The ACS group had a higher prevalence of men, diabetes, hypertension, congestive heart failure, peripheral vascular disease, and a history of percutaneous coronary intervention (PCI). In the ACS group, 101 patients (7.1%) developed cardiogenic shock, whereas 120 patients (8.5%) developed ventricular arrhythmias. Overall, 141 patients (9.9%) in the ACS group died during readmissions (vs 3.0% in the non-ACS group, p <0.001). Among the ACS group, PCI was performed in 33 (5.9%), whereas coronary bypass grafting was performed in 12 (0.82%). The factors associated with ACS readmission included a history of diabetes, congestive heart failure, chronic kidney disease, and PCI, and nonelective TAVI. Coronary artery bypass grafting was an independent factor related to in-hospital mortality during ACS readmission (odds ratio 11.9, 95% confidence interval 2.18 to 65.4, p = 0.004), whereas PCI was not (odds ratio 0.19, 95% confidence interval 0.03 to 1.44, p = 0.11). In conclusion, patients readmitted with ACS have significantly higher mortality compared with those readmitted without ACS. History of PCI is an independent factor associated with ACS after TAVI.

Impact of Transcatheter Aortic Valve Implantation on Severe Gastrointestinal Bleeding in Patients With Aortic Stenosis.

To investigate the effectiveness of transcatheter aortic valve implantation (TAVI) for resolving gastrointestinal bleeding (GIB) in patients with severe GIB and severe aortic stenosis. This was an observational study of consecutive TAVI procedures from 2011 to 2018, identified through a prospectively maintained institutional database. Patients with severe GIB defined as abnormal hemoglobin/hematocrit and overt bleeding or positive fecal occult blood test. Groups were compared for differences in baseline clinical and procedural characteristics and post-TAVI outcomes. A total of 1,192 patients who underwent TAVI were identified, of which 164 patients (13.8%) were found to have had severe GIB. Society of Thoracic Surgeons-Predicted Risk of Mortality scores were higher in the severe GIB group than in the non-GIB group (8.8 ± 5.3 vs 7.6 ± 4.5, p = 0.002). The 30-day mortality was similar across each group (p >0.05), with overall 30-day mortality being 3.2% (38 of 1,192) for the entire cohort. Of the 164 TAVIs with severe GIB, 130 (79.3%) had resolution of their GIB after their TAVI. Patients without resolution of their GIB had higher aortic valve mean pressure gradients after their TAVI (15.0 ± 5.3 vs 9.0 ± 4.3). In conclusion, TAVI was associated with substantial reductions in severe GIB. Despite higher baseline risk, patients with severe GIB achieved similar outcomes, including 30-day mortality, compared with patients without GIB. TAVI may be a safe and effective treatment for patients with severe aortic stenosis and severe GIB, whereas persistently high transvalvular pressure gradients after TAVI may be related to the likelihood of recurrent GIB.

Transfemoral Versus Subclavian Access for Transcatheter Aortic Valve Replacement.

Objective: This study sought to compare outcomes of transcatheter aortic valve replacement (TAVR) performed through subclavian access with those performed through transfemoral access. Methods: This was an observational study utilizing an institutional TAVR database from 2010 to 2018. All patients undergoing a TAVR via a transfemoral (TF-TAVR) or subclavian (SC-TAVR) approach were included in the study. The groups were analyzed for differences in operative mortality and postoperative outcomes. Multivariable Cox analysis was performed to identify variables associated with long-term survival after TAVR. Results: Of the 1,095 patients identified, 133 patients underwent SC-TAVR and 962 patients underwent TF-TAVR. Patients who underwent SC-TAVR were younger, more likely to have chronic lung disease and peripheral vascular disease, had higher Society of Thoracic Surgeons predicted risk of mortality scores, and were more likely to have self-expanding valves placed (P < 0.05). Operative mortality was similar between the TF-TAVR (2.7%) and SC-TAVR (3.8%) groups. There were no significant differences in stroke, length of stay, 30-day readmission, blood transfusions, acute kidney injury, need for permanent pacemaker, paravalvular leak, or major vascular complications between the groups (P > 0.05). The unadjusted Kaplan-Meier survival estimate for TF-TAVR was significantly higher than for SC-TAVR (P = 0.009, log-rank). However, on multivariable Cox analysis, subclavian access was not significantly associated with an increased hazard of death as compared with transfemoral access (P = 0.21). Conclusions: Outcomes of SC-TAVR are comparable to those of TF-TAVR. Subclavian access may be a favorable alternative approach when TF-TAVR is contraindicated.

Current Status of Transcatheter Tricuspid Valve Therapies.

Tricuspid regurgitation is a complex disease that carries a poor prognosis, and surgical repair is associated with high mortality. In light of the success of other transcatheter-based valve interventions, transcatheter tricuspid therapy has recently seen exponential use both clinically and in innovation. Given the rapid development of many tricuspid systems and multiple on-going clinical trials, the aim of this review is to highlight the current state of transcatheter tricuspid therapeutics and to provide an up-to-date view of their clinical use, outcomes and future directions.

Outcomes of Surgical Aortic Valve Replacement After Transcatheter Aortic Valve Implantation.

Few studies have reported their experience in explantation of a transcatheter heart valve. We found 2,100 patients who underwent transcatheter aortic valve implantation (TAVI) from 2013 through 2021. Of 2,100, a total of 17 patients underwent surgical aortic valve replacement after TAVI, including surgical bailout. The mean age was 78.3 years. Co-morbidities were very frequent, including coronary artery disease (70.6%), atrial fibrillation (52.9%), cerebrovascular disease (47.1%), and pulmonary hypertension (41.2%). A history of cardiac surgery was observed in 6 patients (35.3%). The mean predicted risk of mortality at the time of TAVI was 7.7%. Surgical bailout was the most common indication of valve explantation (n = 8, 47.1%), followed by infective endocarditis (n = 4, 23.5%) and paravalvular leak (n = 2, 11.8%). The valve-in-valve TAVI was not feasible because of endocarditis, paravalvular leak, and history of valve-in-valve TAVI. Overall, 13 (76.5%) were performed urgently or emergently, and 10 (58.9%) required aortic root reconstruction. The mean cardiopulmonary bypass time was 158.5 minutes. In-hospital mortality was 41.2%. Transcatheter heart valve explantation continues to be rare; however, these data will continue to be informative as TAVI explantations will become more common with time.

Peripheral arterial ischemic events in cancer patients.

Thromboembolic complications are the second leading cause of death in cancer patients. In contrast to the large body of literature on venous thromboembolism (VTE), relatively few reports have focused on the pathogenesis, incidence, management and outcomes of arterial thromboembolic events in patients with malignancy. The purpose of this article is to review the current literature on the etiology, mechanisms, and prognosis of arterial thromboembolic events in cancer patients and outline appropriate screening and management guidelines that may help lower the rates of morbidity and mortality related to these events.

Transcatheter Tricuspid Valve-in-Valve and Valve-in-Ring Implantation for Degenerated Surgical Prosthesis.

With explosive growth in the field of transcatheter therapies in recent years, transcatheter valve-in-valve implantation has rapidly emerged as a viable, low-risk alternative to high-risk redo surgical interventions. The authors review the fundamental clinical principles of transcatheter tricuspid valve-in-valve and valve-in-ring implantation as pertinent to the procedural steps and technique.

A Novel Technique to Reduce Contrast Exposure During Subclavian Interventions.

We describe a novel technique to minimize total body contrast exposure during endovascular angiography. A patient with severe renal impairment and history of contrast-induced nephropathy was referred for subclavian artery intervention. Angiography and intervention was performed via transfemoral access, while a transradial sheathless-guiding catheter was used to aspirate injected contrast/blood mix from the downstream axillary artery. Semiquantitative analysis indicated approximately 50% of the injected contrast was retrieved. Adaptation of this simple strategy could be considered for selected coronary, lower extremity, and carotid procedures, using contrast removal techniques from the coronary sinus, femoral, and jugular veins.

Differential cardiovascular profiles of sodium-glucose cotransporter 2 inhibitors: critical evaluation of empagliflozin.

One of the most feared repercussions of type 2 diabetes mellitus is the risk of adverse cardiovascular outcomes. The current antidiabetic agents on the market have had difficulty in showing cardiovascular outcome improvement. The EMPA-REG OUTCOME trial studied the sodium-glucose cotransporter 2 inhibitor empagliflozin in type 2 diabetic patients at high risk of cardiovascular events. The trial results revealed a decrease in the composite primary end points of death from cardiovascular causes, nonfatal myocardial infarction, and nonfatal stroke in those taking empagliflozin vs placebo. Those taking the medication also had a significant decrease in death from any cause, death from cardiovascular cause, and hospitalization for heart failure. The EMPA-REG trial is paradigm shifting because it demonstrates a clear mortality benefit to cardiovascular outcomes with a low side-effect profile, in contrast to prior outcome studies of hypoglycemic agents. Further studies are required to better clarify the long-term safety and efficacy of this promising class of diabetic drugs.

Echocardiographic and Fluoroscopic Fusion Imaging for Procedural Guidance: An Overview and Early Clinical Experience.

There has been significant growth in the volume and complexity of percutaneous structural heart procedures in the past decade. Increasing procedural complexity and accompanying reliance on multimodality imaging have fueled the development of fusion imaging to facilitate procedural guidance. The first clinically available system capable of echocardiographic and fluoroscopic fusion for real-time guidance of structural heart procedures was approved by the US Food and Drug Administration in 2012. Echocardiographic-fluoroscopic fusion imaging combines the precise catheter and device visualization of fluoroscopy with the soft tissue anatomy and color flow Doppler information afforded by echocardiography in a single image. This allows the interventionalist to perform precise catheter manipulations under fluoroscopy guidance while visualizing critical tissue anatomy provided by echocardiography. However, there are few data available addressing this technology's strengths and limitations in routine clinical practice. The authors provide a critical review of currently available echocardiographic-fluoroscopic fusion imaging for guidance of structural heart interventions to highlight its strengths, limitations, and potential clinical applications and to guide further research into value of this emerging technology.

Perioperative Cardiovascular Risk of Prior Coronary Stent Implantation Among Patients Undergoing Noncardiac Surgery.

BACKGROUND: Previous studies have observed high rates of perioperative cardiovascular events in patients with coronary stents undergoing noncardiac surgery (NCS). It is uncertain whether this finding reflects an independent association. OBJECTIVES: The goal of this study was to assess the independent relationship between prior coronary stent implantation and the occurrence of perioperative major adverse cardiac and cerebrovascular events (MACCE) and bleeding and its relation with time from stenting to NCS. METHODS: A total of 24,313 NCS cases at the Mayo Clinic (Rochester, Minnesota) from 2006 through 2011 were included in the study; 1,120 (4.6%) cases involved patients with coronary stents. MACCE was defined as death, myocardial infarction, cardiac arrest, or stroke. Age-adjusted odds ratios (aORs) were calculated after propensity adjustment for Revised Cardiac Risk Index factors and other conventional risk factors. RESULTS: The 30-day MACCE rates were 3.7% and 1.5% in stented and unstented patients, respectively (p < 0.001). The risk of MACCE was largely related to the time from stent implantation to NCS, indicating substantially elevated risk in the first year after stenting (aOR: 2.59; 95% confidence interval [CI]: 1.36 to 4.94) but not thereafter (aOR: 0.89; 95% CI: 0.59 to 1.36). Bleeding displayed a similar pattern, indicating elevated risk in the first year after stenting (aOR: 2.23; 95% CI: 1.55 to 3.21) but not thereafter (aOR: 1.07; 95% CI: 0.89 to 1.28). Subgroup analysis in patients with known stent type found that the increased risk of both MACCE and bleeding >1 month after stent implantation was not limited to only those with drug-eluting stents. CONCLUSIONS: This study found that prior coronary stent implantation is an independent risk factor for MACCE and bleeding when time from stenting to NCS is <1 year, both in patients with bare-metal and drug-eluting stents.

Techniques and Outcomes of Percutaneous Aortic Paravalvular Leak Closure.

OBJECTIVES: The aim of this study is to provide a summary of the currently applied aortic paravalvular leak (PVL) closure techniques and describe the procedural and long-term outcomes in a large consecutive cohort of patients. BACKGROUND: Percutaneous repair has emerged as an effective therapy for patients with PVL. To date, clinical outcome data on percutaneous closure of aortic PVL are limited. METHODS: All patients who underwent catheter-based treatment of aortic PVL between 2006 and 2015 were identified. Procedural and short-term results were assessed. Patients were contacted for clinical events and symptoms. RESULTS: Eighty-six procedures were performed in 80 patients. The mean age was 68 ± 15 years, and 70% were men. The primary indications for PVL closure were symptoms of heart failure, hemolysis, and both in 83%, 5%, and 12%, respectively. Successful device deployment was accomplished in 94 defects (90%). Reduction in PVL to mild or less was achieved in 62% of patients. In-hospital major adverse events occurred in 8% of procedures. Symptomatic improvement at 30 days was achieved in 64% of patients. Patients who had reduction in the PVL grade to mild or less experienced more improvement in New York Heart Association functional class (from 2.93 ± 0.62 to 1.72 ± 0.73) compared with those with mild or greater residual leak (from 3.03 ± 0.57 to 2.52 ± 0.74) (p < 0.001). In patients with severe hemolysis (n = 8), transfusion requirements were eliminated in 7 (88%) after PVL closure. Kaplan-Meier survival analysis showed that the cumulative probability of freedom from repeat surgery at 2 years was 98 ± 2% in patients who had mild or less residual leak compared with 68 ± 10% in patients with higher grades of residual PVL (log-rank p = 0.004). CONCLUSIONS: Percutaneous reduction of aortic PVL is associated with durable symptom relief and lower rates of repeat cardiac surgery. The magnitude of benefit is greatest with PVL reduction to a grade of mild or less. Therefore, attempts should be made to reduce PVL as much as possible.