Transcatheter mitral valve replacement: an update.

PURPOSE OF REVIEW: A significant number of patients with mitral valve disease are at high to prohibitive risk for surgical repair or replacement. Transcatheter mitral valve interventions have evolved over the last few years. We review the recent growing evidence on transcatheter mitral valve replacement (TMVR). RECENT FINDINGS: Tendyne is the first TMVR device commercially approved in Europe. All TMVR systems remain under investigation in the United States. Several early studies have reported the feasibility and safety outcomes for TMVR implanted via transapical or transseptal approach. TMVR using balloon expandable valve for degenerated bioprosthetic valves, surgical rings and mitral annular calcification appears feasible in selected patients. SUMMARY: Early experience with TMVR systems is promising. Larger ongoing studies will help understand longer term outcomes and offer insights into patient selection.

Revising the Maximal Contrast Dose for Predicting Acute Kidney Injury following Coronary Intervention.

INTRODUCTION: The maximal allowable contrast dose (MACD = 5 × body weight/serum creatinine) is an empiric equation that has been used and validated in several studies to mitigate the risk of contrast-induced acute kidney injury (CI-AKI). However, coefficient 5 (referred to as factor K) was empirically devised and never disputed. The aim of this study was to refine the MACD equation for the prediction of CI-AKI following percutaneous coronary interventions (PCIs). METHODS: This is a single-center, retrospective cohort study of adults undergoing PCI. Electronic medical records were reviewed to identify patients who underwent PCI between 2010 and 2019, derived from the National Cardiovascular Data Registry Cath-PCI registry for our hospital. Factor K (defined as contrast volume × serum creatinine/body weight) was calculated for every patient. A receiver operating characteristic (ROC) curve was constructed, and the Youden index was used to identify the optimal cut-off value for factor K in predicting severe (stages 2-3) CI-AKI. RESULTS: Of the 3,506 patients undergoing PCI, 255 (7.2%) developed CI-AKI, and 68 (26.7%) of the 255 experienced severe AKI. Factor K predicted all-stage CI-AKI (area under the ROC curve 0.649; 95% CI 0.611, 0.686) but had better performance for predicting severe (stages 2-3) AKI (0.736; 95% CI 0.674, 0.800). The optimal cut-off value for factor K in predicting severe CI-AKI was 2.5, with a corresponding sensitivity of 68.7% and specificity of 70.5%. On subgroup analyses, optimal cut-off values for factor K for high-risk groups were not significantly different from those of low-risk groups. CONCLUSION: Our study indicates that factor K in the MACD equation is an independent risk factor for the development of severe CI-AKI, with an optimal cut-off value of 2.5. If our findings are validated, the MACD equation should be revised to incorporate the coefficient of 2.5 instead of 5.

Subcutaneous furosemide for the treatment of heart failure: a state-of-the art review.

The prevalence of heart failure (HF) is on the rise. By 2030, over eight million Americans (46% increase from current prevalence) will have heart failure. In the USA, approximately 30 billion dollars is spent annually on heart failure and this number will likely double in 2030. Thus, HF represents a significant economic burden. Acute decompensated heart failure (ADHF) is a clinical spectrum, which refers to increasing symptoms and signs of heart failure prompting an emergency room visit or hospitalization. In ADHF, inpatient administration of intravenous diuretic is the standard of care due to the variability in the absorption of oral diuretics. Within 30 days, 25-30% of these patients are readmitted with recurrent ADHF. Recent efforts have focused in reducing HF readmission, and thereby decreasing costs; hence, innovative outpatient treatment options have emerged. Subcutaneous furosemide use will potentially overcome the need to place intravenous lines, reduce associated expenses, and enable management of ADHF at home. This review presents data on the pharmacodynamics and pharmacokinetics of subcutaneous furosemide, scientific evidence on the use of this therapy in the palliative and hospice population, and its experimental use as an outpatient therapy and/or as a bridge from inpatient to home.

Management of common femoral artery occlusive disease: A review of endovascular treatment strategies and outcomes.

Isolated atherosclerotic lesions of the common femoral artery (CFA) are rare but can produce significant claudication and critical limb ischemia. To date, the "gold standard" treatment for this entity has been common femoral endarterectomy (CFE) with or without patch angioplasty. However, surgery does have significant early postoperative complications, with a 15% combined mortality/morbidity. This manuscript sought to perform a comprehensive review of all studies and available data on endovascular treatment of isolated CFA disease and compare its utility to the traditional gold standard treatment. Twenty-one studies from 1987 to 2018 were included exploring the various CFA endovascular therapies (percutaneous transluminal angioplasty, intravascular stenting, drug-coated balloons, and directional atherectomy employed to treat CFA disease, in terms of efficacy, safety, and complications). As a conclusion, endovascular interventions provide acceptable short-term technical outcomes for CFA disease while limiting procedural complications. While only two randomized controlled trials compare short and long-term outcomes of surgical versus endovascular treatment, further studies are required to clarify the role of endovascular therapy.

Validation and comparison of non-hyperemic pressure reserve to fractional flow reserve for assessment of coronary artery stenosis: A real world study.

BACKGROUND: The visual interpretation of an angiographic stenosis may not always reflect the physiological significance of a lesion. Fractional Flow Reserve (FFR) is a reliable index to assess the significance of a lesion during hyperemia. However, there are pitfalls that can lead to significant misinterpretation and adverse events. OBJECTIVE: This study sought to evaluate the accuracy and predictability of the non-hyperaemic pressure ratio (NHPR) without hyperemic stimuli, compared to hyperemic FFR. METHODS: We conducted a retrospective, multicenter study of 700 patients who underwent a pressure recording during coronary angiography using NHPR and FFR measurements. Receiver operator characteristic (ROC) curve was constructed. NHPR sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy test were calculated. The most accurate NHPR cutoff was determined. RESULTS: Of the 700 procedures, 449 cases were included. By ROC analysis, the optimal cut-point for NHPR was 0.93 to predict an FFR of ≤0.80 with an overall diagnostic accuracy of 78.84%. The sensitivity of this NHPR cutoff was 85.06%, specificity of 75.59%, PPV of 64.53% and a NPV of 90.65%. There was an overall accuracy of about 80% for predicting non-hyperemic index (FFR < 0.80) using a cutoff of NHPR ≤ 0.93. CONCLUSIONS: The use of NHPR can be considered in certain clinical scenarios where adenosine is contraindicated or there are other challenges; with the knowledge that hyperemia might be necessary if there is any high clinical suspicion as it still remains the reference standard for diagnostic certainty.

Maximum allowable contrast dose and prevention of acute kidney injury following cardiovascular procedures.

PURPOSE OF REVIEW: Contrast-induced acute kidney injury (CI-AKI) is a serious complication. Although nonmodifiable and modifiable risk factors have been thoroughly characterized, the utility of the maximal allowable contrast dose (MACD) has not received adequate attention. The focus of this review is to provide a critical appraisal of this modifiable risk factor. RECENT FINDINGS: Several retrospective and prospective cohort studies have demonstrated that the incidence of CI-AKI among patients receiving contrast media in volumes exceeding the MACD is consistently higher compared with those who do not exceed the MACD (an average of 24 vs. 6%). Furthermore, the MACD is independent predictor of CI-AKI and other adverse events. A two-step algorithm incorporating the determination of the MACD and the contrast volume to eGFR ratio prior to a planned cardiovascular procedure is a sound approach to minimize contrast volume and prevent CI-AKI. SUMMARY: Prevention of CI-AKI must remain a clinical priority. Intraprocedural preventive measures should include a priori calculation of the MACD and contrast volume to eGFR ratio to limit contrast volume. Other measures may include the adoption of the transradial approach, the use of automated contrast injectors and small catheters to limit contrast volume, the use of low-osmolar contrast agents, and if necessary the use of staged procedures. We call for the system-wide implementation of evidence-based care bundles to prevent CI-AKI.

A Comprehensive Evaluation of the NAVITOR Transcatheter Aortic Valve Replacement System.

Transcatheter aortic valve replacement (TAVR) has undergone significant advancements in the last two decades, expanding its indications and refining transcatheter heart valve (THV) and delivery system designs to improve procedural success and patient outcomes. This review focuses on the Navitor™ valve, a third-generation intra-annular Portico™ valve (Abbott Structural Heart, St Paul, MN, USA) designed to address TAVR complications, particularly paravalvular leak (PVL). We present an overview of the Navitor™ system, comparing it to the first-generation Portico™ THV in terms of THV design, key iterations and clinical outcomes. The Navitor™ THV introduces two key refinements-a protective outer sealing skirt and a more flexible delivery system. These enhancements have led to a significant reduction in 30 day PVL rates, from 6.3% with the first-generation Portico™ to 0% with the Navitor™ system. Additionally, the Navitor™ system exhibited lower rates of severe bleeding (27.3% versus 13.1%) and major vascular complications (5.8% versus 0.7%) compared with the first-generation Portico™. The Navitor™ valve represents a promising advancement in TAVR technology, with notable reductions in complications such as PVL, severe bleeding, and major vascular issues, compared with its predecessor. While further research is needed to assess long-term durability, these results underscore its potential benefits in enhancing patient outcomes and reducing complications. This review provides insights into the evolving landscape of TAVR technology and its quantifiable impact on patient care.

Patent Foramen Ovale and Atrial Septal Defect.

Patent foramen ovale (PFO) and atrial septal defects (ASDs) are two types of interatrial communications with unique clinical presentations and management strategies. The PFO is a normal part of fetal development that typically closes shortly after birth but may persist in as many as 25% to 30% of adults. The communication between atria may result in paradoxic embolism and embolic stroke. On the other hand, ASDs (anatomically defined as secundum, primum, sinus venosus, and coronary sinus in order of prevalence) typically result in right heart volume overload and are often associated with other congenital defects. The diagnostic methods, treatment options including surgical and percutaneous approaches, and potential complications are described. Both conditions underline the significance of precise diagnosis and appropriate management to mitigate risks and ensure optimal patient outcomes.

Prognostic Value of Right Ventricular Afterload in Patients Undergoing Mitral Transcatheter Edge-to-Edge Repair.

BACKGROUND: Pulmonary hypertension (PH) and secondary mitral regurgitation (MR) are associated with adverse outcomes after mitral transcatheter edge-to-edge repair. We aim to study the prognostic value of invasively measured right ventricular afterload in patients undergoing mitral transcatheter edge-to-edge repair. METHODS AND RESULTS: We identified patients who underwent right heart catheterization ≤1 month before transcatheter edge-to-edge repair. The end points were all-cause mortality and a composite of mortality and heart failure hospitalization at 2 years. Using the receiver operating characteristic curve-derived threshold of 0.6 for pulmonary effective arterial elastance ([Ea], pulmonary artery systolic pressure/stroke volume), patients were stratified into 3 profiles based on PH severity (low elastance [HE]: Ea <0.6/mean pulmonary artery pressure (mPAP)) <35; High Elastance with No/Mild PH (HE-): Ea ≥0.6/mPAP <35; and HE with Moderate/Severe PH (HE+): Ea ≥0.6/mPAP ≥35) and MR pathogenesis (Primary MR [PMR])/low elastance, PMR/HE, and secondary MR). The association between this classification and clinical outcomes was examined using Cox regression. Among 114 patients included, 50.9% had PMR. Mean±SD age was 74.7±10.6 years. Patients with Ea ≥0.6 were more likely to have diabetes, atrial fibrillation, New York Heart Association III/IV status, and secondary MR (all P<0.05). Overall, 2-year cumulative survival was 71.1% and was lower in patients with secondary MR and mPAP ≥35. Compared with patients with low elastance, cumulative 2-year event-free survival was significantly lower in HE- and HE+ patients (85.5% versus 50.4% versus 41.0%, respectively, P=0.001). Also, cumulative 2-year event-free survival was significantly higher in patients with PMR/low elastance when compared with PMR/HE and patients with secondary mitral regurgitation (85.5% versus 55.5% versus 46.1%, respectively, P=0.005). CONCLUSIONS: Assessment of the preprocedural cardiopulmonary profile based on mPAP, MR pathogenesis, and Ea guides patient selection by identifying hemodynamic features that indicate likely benefit from mitral-transcatheter edge-to-edge repair in PH or lack thereof.

Impact of Left Atrial Pressure on Outcomes After Mitral Transcatheter Edge-to-Edge Repair.

BACKGROUND: Increased left atrial pressure (LAP) has been associated with adverse outcomes after mitral transcatheter edge-to-edge repair (M-TEER). We sought to evaluate outcomes based on differences in postprocedural LAP measured after the final clip deployment. METHODS: We included consecutive patients who underwent M-TEER at our institution between 2014 and 2022 with LAP monitoring. Patients were stratified into 3 groups according to tertiles of post-TEER mean LAP. Outcomes were assessed using Kaplan-Meier analysis and Cox proportional hazards models. RESULTS: We included 273 patients (mean age, 76.8±10.8 years; 42.5% women; 78.4% White). The mean post-TEER LAP was 8.7±1.7 mm Hg in tertile 1 (n=85), 14.4±1.6 mm Hg in tertile 2 (n=95), and 21.9±3.8 mm Hg in tertile 3 (n=93). In comparison with tertile 1, both tertiles 2 and 3 were associated with increased risk of all-cause mortality or heart failure hospitalization at 2 years (adjusted hazard ratio [adjHR], 2.27 [95% CI, 1.25-4.12] and adjHR, 3.00 [95% CI, 1.59-5.64], respectively). Among patients with primary mitral regurgitation, higher LAP was associated with increased risk of 2-year all-cause mortality or heart failure hospitalization (tertile 2 versus 1: adjHR, 3.00 [95% CI, 1.37-6.56]; tertile 3 versus 1: adjHR, 5.52 [95% CI, 2.04-14.95]). However, in patients with secondary mitral regurgitation, neither being in tertile 2 (adjHR, 1.53 [95% CI, 0.55-4.24]) nor tertile 3 (adjHR, 2.18 [95% CI, 0.82-5.77]) were associated with the composite outcome compared with tertile 1. Any degree of LAP reduction following M-TEER was associated with lower mortality or heart failure hospitalization compared with no LAP reduction (adjHR, 0.59 [95% CI, 0.39-0.88]). CONCLUSIONS: Elevated LAP after M-TEER was associated with increased 2-year risk of mortality or heart failure hospitalization. Exploration of reasons for elevated LAP after M-TEER and ways to lower it warrant further investigation.

Transcatheter Mitral Valve Replacement with Dedicated Devices.

Mitral regurgitation is the most common form of valvular heart disease. The anatomy and pathophysiology of mitral valve regurgitation are very complex, and dedicated devices are required for transcatheter mitral valve replacement in patients with a high or prohibitive surgical risk. In the United States, all transcatheter mitral valve replacement devices are still being studied and are not yet approved for commercial use. Early feasibility studies have demonstrated good technical success and short-term outcomes, but larger samples and longer-term outcomes still need to be assessed. Furthermore, significant advances in device technology, delivery systems, and implantation techniques are essential to avoid left ventricular outflow tract obstruction, and valvular and paravalvular regurgitation as well as ensuring good anchoring of the prosthesis.

Tricuspid Regurgitation Related Mortality in United States, 1999-2019.

Tricuspid regurgitation (TR) is being increasingly recognized in patient population. We aimed to investigate the long-term mortality due to TR in the United States (US) and demographic disparities in TR-related mortality using "Multiple Cause of Death data" via the Centers for Disease Control and Prevention Wide-Ranging On-line Data for Epidemiologic Research datasets, 1999 to 2019. The results from present analysis suggest that TR related deaths in the US may have increased over the last 20 years. This trend may justify greater focus on timely diagnosis and management of TR.

Assessment of Repeat Revascularization in Percutaneous Coronary Intervention Randomized Controlled Trials as a Surrogate for Mortality: A Meta-Regression Analysis.

The association of repeat revascularization after percutaneous coronary intervention (PCI) with mortality is uncertain. To assess the association of repeat revascularization after PCI with mortality in patients with coronary artery disease (CAD). We identified randomized controlled trials comparing PCI with coronary artery bypass graft (CABG) or optimal medical therapy (OMT) using electronic databases through January 1, 2022. We performed a random-effects meta-regression between repeat revascularization rates after PCI (absolute risk difference [%] between PCI and CABG or OMT) with the relative risks (RR) of mortality. We assessed surrogacy of repeat revascularization for mortality using the coefficient of determination (R2), with threshold of 0.80. In 33 trials (21,735 patients), at median follow-up of 4 (2-7) years, repeat revascularization was higher after PCI than CABG [RR: 2.45 (95% confidence interval, 1.99-3.03)], but lower vs OMT [RR: 0.64 (0.46-0.88)]. Overall, meta-regression showed that repeat revascularization rates after PCI had no significant association with all-cause mortality [RR: 1.01 (0.99-1.02); R2=0.10) or cardiovascular mortality [RR: 1.01 (CI: 0.99-1.03); R2=0.09]. In PCI vs CABG (R2=0.0) or PCI vs OMT trials (R2=0.28), repeat revascularization did not meet the threshold for surrogacy for all-cause or cardiovascular mortality (R2=0.0). We observed concordant results for subgroup analyses (enrollment time, follow-up, sample size, risk of bias, stent types, and coronary artery disease), and multivariable analysis adjusted for demographics, comorbidities, risk of bias, MI, and follow-up duration. In summary, this meta-regression did not establish repeat revascularization after PCI as a surrogate for all-cause or cardiovascular mortality.

New perspectives on contrast-induced nephropathy during coronary interventions.

Tweetable abstract To reduce contrast-induced nephropathy as a complication of percutaneous coronary intervention, several thresholds have been proposed, including maximum contrast dose, contrast volume/estimated glomerular filtration rate, revised maximal contrast dose and zero-contrast percutaneous coronary intervention in select patients.

To reduce contrast-induced nephropathy as a complication of percutaneous coronary intervention, several thresholds have been proposed, including maximum contrast dose, contrast volume/estimated glomerular filtration rate, revised maximal contrast dose and zero-contrast percutaneous coronary intervention in select patients.

New Onset Coronary Obstruction in Established Nonischemic Heart Failure: A Late Consequence of Radiation.

The column in this issue is provided by Salil Kumar, MD, and Joe Aoun, MD, chief cardiology fellows in the Houston Methodist Cardiology Department, and Arvind Bhimaraj, MD, associate professor of Clinical Cardiology at the Houston Methodist Academic Institute. Dr. Bhimaraj specializes in cardiovascular disease and advanced heart failure and transplantation.

Muscle fat index is associated with frailty and length of hospital stay following transcatheter aortic valve replacement in high-risk patients.

BACKGROUND: Aging is associated with progressive loss of muscle mass, as well as replacement of muscle with fat and fibrous tissue. We studied the contribution of muscle fat content, a surrogate marker of biological aging, to frailty and Length of Hospital Stay (LOS) following Transcatheter Aortic Valve Replacement (TAVR). METHODS: We evaluated 415 patients who underwent TAVR from February 2012 to December 2016 at Mayo Clinic, MN, USA. Densities between -190 to -30 Hounsfield Units within the abdominal muscle area were determined as muscle fat. Muscle Fat Index (MFI) was defined as muscle fat mass divided by height squared. LOS was considered as the primary outcome. Stepwise multivariable linear regression was used to identify the predictors of LOS. RESULTS: Mean age ± SD of the study population was 81.2 ± 9.6 years and 58.07% were male. Seventy-two patients (17.35%) had frailty. Median (IQR) LOS was 4 (3-6) days. MFI was higher in patients with frailty (median (IQR); 18.1 [13.8-24.2] vs 14.4 [10.6-18.7], p < 0.001) and was positively correlated with LOS (r = 0.129, p = 0.009). In multivariable analysis of predictors of LOS, MFI (ß = 0.06, p = 0.022), pre-TAVR atrial fibrillation/flutter (ß = 0.5, p = 0.015), and post-TAVR complications (ß = 0.91, p < 0.001) were directly, and femoral access route (ß = -1.13, p < 0.001) and pre-TAVR hemoglobin (ß = -0.35, p = 0.002) were inversely associated with LOS. CONCLUSIONS: MFI can be determined from pre-TAVR CT scans and is a novel predictor of LOS following TAVR. This objective indicator can potentially be used in a pre-TAVR clinic to plan for rehabilitation programs in selected patients.

Refractory Impella Suction Alarms in the Setting of Extracorporeal Membrane Oxygenation.

Cardiogenic shock is an uncommon but serious complication of acute myocardial infarction. Temporary mechanical circulatory support devices are being used more often in this setting, and physicians are required to be familiar with their complications. Although veno-arterial extracorporeal membrane oxygenation increases after loading, an Impella device can be inserted to unload the left ventricle and decrease its oxygen consumption. Here, we present an uncommon cause of a refractory Impella suction alarm, which was related to the migration of the venous extracorporeal membrane oxygenation cannula into the left atrium.

Le choc cardiogénique est une complication rare, mais grave, de l'infarctus aigu du myocarde. Des dispositifs d'assistance circulatoire mécanique temporaires sont de plus en plus utilisés dans de telles situations, et les médecins doivent bien connaître les complications possibles de ces dispositifs. Bien que l'oxygénation par membrane extracorporelle veino-artérielle augmente la postcharge, une pompe Impella peut être insérée pour décharger le ventricule gauche et diminuer sa consommation d'oxygène. Dans cet article, nous présentons une cause rare d'une alarme d'aspiration réfractaire de la pompe Impella, attribuable à la migration de la canule veineuse d'oxygénation par membrane extracorporelle dans l'oreillette gauche.

Management of Acute Coronary Syndrome in the COVID Era.

Management of acute coronary syndrome (ACS) has emerged as a challenge during the COVID-19 era. There has been a significant increase in the morbidity and mortality associated with ACS both as a direct and an indirect consequence of the pandemic. In this review, we provide an overview of the impact of COVID-19 on patients presenting with ACS and current practices for managing patients presenting with chest pain during the pandemic and for ensuring safety of healthcare professionals. We also discuss treatment strategies and post-ACS care along with current and future perspectives for management of ACS during future waves of COVID-19 infection or similar pandemics.

Diagnosis and Management of Late-presentation ST-elevation Myocardial Infarction and Complications.

The incidence of late presentation of myocardial infarction varies between 8.5% and 40%. Late revascularization of an infarct-related artery may limit infarct size and remodeling, reduce electrical instability, and may provide supplemental blood supply to that area via collaterals. Randomized clinical trials have shown a benefit of revascularization in symptomatic and hemodynamically unstable latecomers. Image stress testing can be beneficial to guide management of asymptomatic late presenters. Higher rates of myocardial infarction complications occur with late presentations, so a high level of suspicion is required for early diagnosis. Surgical repair remains the gold standard for management of mechanical complications.

Mechanical Prosthetic Aortic Valve Thrombosis Complicated by an Acute Coronary Syndrome During Fibrinolysis.

A 70-year-old man with mechanical aortic and mitral valves was admitted with progressive shortness of breath. He was found to have thrombosis of the aortic valve prosthesis. Treatment with intravenous thrombolysis was complicated by an acute coronary syndrome related to coronary embolism. The patient was successfully managed conservatively with long-term anticoagulation. An algorithm for the management of coronary embolism is suggested. (Level of Difficulty: Advanced.).