Percutaneous Transseptal Extracorporeal Membrane Oxygenation to Rescue a Failing Right Ventricle in an Animal Model.

OBJECTIVE: We tested the feasibility and effectiveness of a percutaneous atrial transseptal extracorporeal membrane oxygenation (ECMO) cannulation strategy in a right ventricular failure (RVF) model. METHODS: We performed 4 nonsurvival porcine experiments. Percutaneous transseptal access was achieved using a steerable introducer. For guidance, we used fluoroscopy, transesophageal echocardiogram (TEE), and intracardiac echocardiography (ICE). A ProtekDuo rapid deployment cannula (LivaNova, London, UK) was advanced across the septum into the left atrium by 2 to 3 cm. Pulmonary hypertension (PH) was induced by partially clamping the pulmonary artery. ECMO flow was cycled from high (2 to 3 L/min) to low (0.2 to 0.3 L/min) over 2 to 3 hours. RESULTS: Transseptal access using TEE and fluoroscopy was successful in 1 animal and unsuccessful in 1 animal. ICE provided optimal visualization for the remaining 2 animals. Mean arterial pressure (MAP) was associated immediately and consistently with high versus low ECMO flow rate (mean difference: 29 ± 3.1 mm Hg, P = 0.004) but was not restored to baseline values. RV pressure values were dynamic. Given time to equilibrate, mean RV pressure was restored to a baseline level. CONCLUSIONS: Percutaneous right atrium to left atrium transseptal cannulation relieved PH-RVF. MAP was restored to a viable level, and mean RV pressure was restored to a baseline level. Transseptal ECMO shows promise as a cannulation strategy to bridge patients with PH-RVF to lung transplant.

Iatrogenic left common carotid artery to right internal jugular vein arteriovenous fistula closure.

We report a minimally invasive approach to the repair of a 2.8-cm × 6.0-cm left proximal common carotid to right internal jugular vein arteriovenous fistula. A 47-year-old woman with coronavirus disease 2019 pneumonia had received extracorporeal membranous oxygenation and developed a rare, presumably cannulation-related, vascular injury. We used a plug designed and typically used for the endovascular management of a patent ductus arteriosus.

Outcomes of Radial Versus Femoral Access in Patients With Severe Aortic Stenosis Undergoing Percutaneous Coronary Intervention Prior to Transcatheter Aortic Valve Replacement.

BACKGROUND: The safety and feasibility of radial access in patients undergoing percutaneous coronary intervention (PCI) prior to transcatheter aortic valve replacement (TAVR) has not been studied. METHODS: This study included consecutive patients who underwent PCI within 30 days before TAVR at Mayo Clinic. Vascular access was left to the discretion of the operator. Baseline demographics, procedural data, PCI outcomes, and subsequent transfemoral TAVR outcomes were extracted from patient charts. RESULTS: A total of 331 patients were included in this study, with 107 patients undergoing PCI via radial access (rPCI), and 224 via femoral access (fPCI). Mean age was 80.6 years and 35.6% were females (35.5% rPCI vs 35.3% fPCI). More patients in the fPCI group had previous coronary artery bypass graft surgery (13.1% rPCI vs 34.4% fPCI; P<.001). Fluoroscopy time (13.36 minutes vs 18.86 minutes; P<.001) and contrast use (115 mL vs 140 mL; P<.01) were lower in the rPCI group than in the fPCI group. Crossover rate from radial to femoral was 6.5%. There were more access-site hematomas in the fPCI group (2.8% rPCI vs 14.3% fPCI; P<.001), with no statistically significant rate of other access-related complications. There was no difference in stroke, myocardial infarction, cardiac arrest, or unplanned surgery. There was no difference in bleeding or stroke between both groups during subsequent transfemoral TAVR. CONCLUSION: Radial access for pre-TAVR PCI is feasible and safe and is associated with a lower rate of access-site hematoma. This study supports the increased use of transradial access for pre-TAVR PCI.

Characteristics and Outcomes After Transcatheter Aortic Valve Implantation in Immunocompromised Patients.

Immunocompromised (IC) patients are at greater risk of adverse outcomes from cardiac surgery, and less invasive options for treating severe aortic stenosis among IC patients are often sought. However, despite greater preference for transcatheter aortic valve implantation (TAVI) in this population, there are limited data on outcomes in IC patients. Between January 2015 and December 2019, we studied patients with severe aortic stenosis who underwent TAVI. We defined IC status by the presence of active malignancy and receipt of oncologic treatment, post-organ transplantation-associated immunosuppression, human immunodeficiency virus, chronic steroid use (>5 mg/day), or active autoimmune disorder, and compared characteristics and outcomes of IC patients with those of non-IC patients. Of 173 patients who underwent TAVI, 56 (32%) were IC, 30 (54%) had active malignancy and underwent active treatment, 19 (34%) were IC without malignancy, and 7 (13%) were both IC and had active malignancy. IC patients, compared with non-IC patients, had similar baseline demographics, Society of Thoracic Surgeons risk scores (median 4.3% vs 4.4%), and overall complications (29% vs 26%). There were 37 deaths (16 IC and 21 non-IC) over a median follow-up of 17 months (95% confidence interval [CI] 14 to 20 months), and 1-year survival after TAVI was 84.0% for IC patients and 89.0% for non-IC patients (p = 0.51 by log-rank). After adjusting for Society of Thoracic Surgeons risk scores, IC patients had a nonsignificant trend toward greater risk of death compared with non-IC patients (adjusted hazard ratio 1.48, 95% CI 0.77 to 2.84). IC patients had a significantly smaller risk of cardiac-related death (adjusted hazard ratio 0.21, 95% CI 0.05 to 0.98) but a greater risk of noncardiac-related death (adjusted hazard ratio 4.14, 95% CI 1.71 to 10.0) than non-IC patients. In conclusion, IC patients who underwent TAVI have similar complication rates as non-IC patients, with a nonsignificant trend toward greater mortality, specifically related to noncardiac causes.

Impact of Persistent Iatrogenic Atrial Septal Defect following MitraClip.

BACKGROUND: Prior studies have reported conflicting results of persistent iatrogenic atrial septal defect (iASD) and its impact following a transcatheter edge-to-edge repair (TEER) procedure. This study aims to evaluate the incidence of iASD and its clinical and hemodynamic impact after a TEER. METHODS: Consecutive patients who underwent a TEER procedure from June 2014 to September 2020 at the Mayo Clinic were identified. The presence of iASD was retrospectively identified on post-procedure transthoracic echocardiography (TTE) to group patients into an iASD+ group and an iASD- group for comparison of prognosis and cardiac function. RESULTS: A total of 316 patients were included; the mean age was 79.1 ± 9.1 years, and 67.7% were male. Persistent iASD was diagnosed in 108 (34.2%) patients. There was no difference concerning all-cause mortality, heart failure hospitalization, and stroke/TIA between groups at follow-up (median follow-up of 9 months). Post-procedure TTE demonstrated no differences regarding right ventricle (RV) and left ventricle (LV) dimensions and function, including TAPSE (15.2 ± 4.6 vs. 15.4 ± 5.5 mm, p = 0.875), and LV ejection fraction (51.1 ± 14.0% vs. 51.3 ± 13.9%, p = 0.933). However, patients with iASD had higher RV systolic pressure (48.7 ± 14.4 vs. 45.5 ± 14.5 mmHg, p = 0.042) compared with patients without iASD. CONCLUSION: Notwithstanding higher RV pressures, patients with persistent iASD had no hemodynamic compromise and an equal prognosis compared with those without a residual atrial defect after a TEER procedure. These findings support the mid-term safety of procedures in which an interatrial defect needs to be created and would argue against the need for interventional closure.

Anatomic Approach to Transseptal Puncture for Structural Heart Interventions.

The use of transseptal puncture continues to rise given the increase in left atrial cardiac interventions. The authors review an anatomic approach to transseptal puncture incorporating multimodality imaging both pre- and intraprocedurally with stepwise escalation algorithms to ensure safe and efficacious large-bore transseptal puncture.

30-day patient reported outcomes can be predicted by change in left atrial pressure and not change in transmitral gradient following MitraClip.

BACKGROUND: Change in left atrial pressure (LAP) has been shown to be associated with symptom improvement post-MitraClip; however, the association between acute procedural changes in transmitral diastolic mean gradient (MG) compared to LAP and symptom improvement is not well established. METHODS: 164 consecutive patients undergoing MitraClip at Mayo Clinic between June 2014 and May 2018 were included. Preclip and postclip MG and LAP were recorded. Baseline demographics, clinical, and echocardiographic outcomes, including 30-day New York Heart Association (NYHA) functional status were obtained from patient charts. RESULTS: Median age was 81.5 years (IQR: 76.3, 87), 34% were female and 94.5% had NYHA class III and IV functional status at baseline. At baseline, median MG was 4 mmHg (IQR: 3, 5) and LAP was 19 mmHg (IQR: 16, 23.5). Following MitraClip deployment, the median MG was 4 mmHg (IQR: 3, 6) and the median LAP was 17 mmHg (IQR: 14, 21), 69.5% of patients had less than moderate MR. There was no statistically significant association between change in MG and NYHA functional class at 30 days (OR = 0.95, 95% CI: 0.76-1.20). However, a reduction in LAP following MitraClip deployment was significantly associated with improvement in NYHA functional status at 30 days following adjustments for age and sex (aOR 3.36, 95% CI: 1.34-8.65). There was no significant correlation between change in mean LAP and change in MG (p = .98). CONCLUSION: Unlike change in left atrial pressure, change in MG post-MitraClip was not associated with patient reported outcomes at 30 days and did not correlate with change in left atrial pressure. Long-term follow up is needed to evaluate the impact of LA pressure on symptoms.

Characteristics and Long-Term Outcomes of Patients With Prior Coronary Artery Bypass Grafting Undergoing Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction.

Limited data are available on characteristics and long-term outcomes of patients with coronary artery bypass grafts (CABG) undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction (STEMI). Between January 2000 to December 2014, we identified STEMI patients with prior CABG undergoing primary percutaneous coronary intervention from 3 sites. Kaplan-Meier methods to estimate survival and major adverse cardiac events (MACE) were employed and compared to a propensity matched cohort of non-CABG STEMI patients. Independent predictors of outcomes were analyzed with Cox modeling. Of the 3,212 STEMI patients identified, there were 296 (9.2%) CABG STEMI patients, having nearly similar frequencies of culprit graft (47.6%) versus culprit native (52.4%) as the infarct-related artery (IRA). At 10 years, the adjusted survival was 44% in CABG STEMI versus 55% in non-CABG STEMI (HR 1.26; 95%CI 0.86 to 1.87; p = 0.72). Survival free of MACE was lower for CABG STEMI (graft IRA, 37%; native IRA, 46%) as compared to non-CABG STEMI controls (63%) (p = 0.02). Neither CABG history nor IRA (native vs graft) was independently associated with death or MACE in multivariable analysis. Temporal trends showed no significant change in death or MACE rates of CABG STEMI patients over time. In conclusion, long term survival of CABG STEMI patients is not significantly different than matched STEMI patients without prior CABG; however, CABG STEMI patients were at significantly higher risk for MACE events.

A hybrid technique for treatment of commissural primary mitral regurgitation.

BACKGROUND: MitraClip is an effective transcatheter therapy for mitral regurgitation (MR). However, MitraClip is challenging in commissural MR and the optimal therapeutic approach is unclear. METHODS: We describe a case series of six consecutive patients with severe commissural primary mitral regurgitation who underwent MitraClip insertion followed by an Amplatzer Vascular Plug (AVP) II occluder between the commissure and the MitraClip. RESULTS: The procedure was successful in all patients. MR was reduced from severe to mild/trivial in 50% and moderate in 50% of cases. On 30-day follow-up, NYHA class had improved from III (6 patients) to I (2 patients), II (2 patients), and III (2 patients). The mean transmitral gradient was 2.5 ± 1.8 mmHg at baseline and 4.8 ± 2.6 mmHg following the procedure. One patient developed hemolysis immediately post procedure. The other five patients remained well during a median follow-up of 20 months (range 5-50 months) with no reported device dislodgement. CONCLUSIONS: Elective treatment of severe commissural MR with a laterally or medially placed MitraClip coupled with an AVP II occluder between the clip and the commissure is feasible and safe. This approach may provide a useful management alternative in selected patients.

Characteristics and long term outcomes of patients with acute coronary syndromes due to culprit left main coronary artery disease treated with percutaneous coronary intervention.

BACKGROUND: Patients with acute coronary syndrome (ACS) due to unprotected culprit left main coronary artery disease (LMCAD) treated with percutaneous coronary intervention (PCI) are rare, high-risk, and not represented in trials. Data regarding long term outcome after PCI are limited. METHODS: Between January 2000 and December 2014, there were 8,794 patients hospitalized with unstable angina/non-ST elevation myocardial infarction (UA/NSTEMI) or ST-elevation myocardial infarction (STEMI) treated with PCI at our institution; of these, 83 (0.94%) patients were identified as having culprit LMCAD ACS. RESULTS: Of the 83 patients with unprotected LMCAD ACS, 40 patients presented with STEMI and 43 patients presented with UA/NSTEMI. As compared to LM UA/NSTEMI, LM STEMI patients were younger and had less hypertension, with a trend towards greater frequency of cardiogenic shock. Distal LM involvement was common in both groups and did not differ by ACS type. In-hospital mortality was 33% in LM STEMI and 9% in LM UA/NSTEMI (P = .009). Over median follow up of 6.3 years, long term survival rates in both groups were similar (46% for STEMI vs 51% for UA/NSTEMI; P = .50 by log-rank). CONCLUSIONS: Unprotected culprit LMCAD ACS necessitating PCI is uncommon, occurring in <1% of cases, but is associated with reduced survival, with long term follow-up noting continued and similar risk of death regardless of index ACS type.

The Evolving Face of Myocardial Reperfusion in Acute Coronary Syndromes: A Primer for the Internist.

Acute coronary syndromes (ACSs) account for a large proportion of disease burden in the United States and worldwide, and our understanding of ACS management continues to evolve. In this review we take a practical approach to evaluating and treating a patient with ACS, focusing on the optimal timing and methods of coronary reperfusion. Beginning with initial assessment and risk stratification, a provider managing the patient with ACS must be able to expeditiously decide on and implement the correct guideline-directed pathway to optimize outcomes. With an ever-growing body and weight of knowledge in this field, the clinician is tasked with several challenges. First, there are a variety of pathways of care to be considered; second, adjunctive medical therapies are expanding; and third, when coupled with the multiple combinations of adjunctive supportive therapies for revascularization, the variety of potential therapeutic options can be overwhelming and confusing. Herein, we carefully review all the relevant guidelines and the contributing literature, taking a 4-step approach: (1) review the importance of risk stratification before engaging in a particular strategy of care, (2) define the reperfusion strategies available, (3) review the specific agents (antiplatelet and anticoagulant) that support reperfusion strategies, and (4) apply the strategies of care in the context of the clinical presentation.

Early Outcomes of Percutaneous Transvenous Transseptal Transcatheter Valve Implantation in Failed Bioprosthetic Mitral Valves, Ring Annuloplasty, and Severe Mitral Annular Calcification.

OBJECTIVES: The aim of this study was to examine 1-year outcomes of transseptal balloon-expandable transcatheter heart valve implantation in failed mitral bioprosthesis, ring annuloplasty, and mitral annular calcification (MAC). BACKGROUND: Immediate outcomes following transseptal mitral valve implantation in failed bioprostheses are favorable, but data on subsequent outcomes are lacking. METHODS: Percutaneous transseptal implantation of balloon-expandable transcatheter heart valves was performed in 87 patients with degenerated mitral bioprostheses (valve in valve [VIV]) (n = 60), previous ring annuloplasty (valve in ring) (n = 15), and severe MAC (valve in MAC) (n = 12). RESULTS: The mean Society of Thoracic Surgeons risk score was 13 ± 8%, and the mean age was 75 ± 11 years. Acute procedural success was achieved in 78 of 87 patients (90%) in the overall group and 58 of 60 (97%) in the VIV group, with a success rate of 20 of 27 (74%) in the valve in ring/valve in MAC group. Thirty-day survival free of death and cardiovascular surgery was 95% (95% confidence interval [CI]: 92% to 97%) in the VIV subgroup and 78% (95% CI: 70% to 86%) in the valve in ring/valve in MAC group (p = 0.008). One-year survival free of death and cardiovascular surgery was 86% (95% CI: 81% to 91%) in the VIV group compared with 68% (95% CI: 58% to 78%) (p = 0.008). At 1 year, 36 of 40 patients (90%) had New York Heart Association functional class I or II symptoms, no patients had more than mild residual mitral prosthetic or periprosthetic regurgitation, and the mean transvalvular gradient was 7 ± 3 mm Hg. CONCLUSIONS: One-year outcomes following successful transseptal balloon-expandable transcatheter heart valve implantation in high-risk patients with degenerated mitral bioprostheses are excellent, characterized by durable symptom relief and prosthesis function. Although mitral valve in ring and valve in MAC have higher operative morbidity and mortality, 1-year outcomes after an initially successful procedure are favorable in carefully selected patients.

Left atrial pressure and predictors of survival after percutaneous mitral paravalvular leak closure.

BACKGROUND: Data on the clinical utility of left atrial (LA) hemodynamic monitoring during percutaneous mitral interventions are limited. OBJECTIVES: To evaluate the association between intraprocedural LA pressures during percutaneous mitral paravalvular leak (PVL) closure and long term survival. METHODS: Patients who underwent mitral PVL repair with invasive LA pressure monitoring were divided at baseline to three tertiles based on their mean final LA pressure (<25%; 25-30%; >30% of mean systolic blood pressure). Primary outcome was all-cause mortality. RESULTS: 134 patients (mean age 68 ± 12 years) were studied. Over 3 year mean follow-up, 81 (38%) patients died. The cumulative probability of death at 3 years was significantly higher among patients in the highest LA pressure tertile (56 ± 8% vs. 28 ± 5%, log rank P < 0.001). More than mild residual mitral regurgitation (MR) by transesophageal echocardiography (TEE) was associated with a 2.5-fold increased risk of death and patients in the highest LA pressure tertile had 2.2-fold higher mortality (P < 0.001 and = 0.003 respectively). After adjustment for residual MR by TEE, each 10% acute procedural reduction in LA pressures was associated with a significant 9% reduced risk of death (P = 0.023). Multivariate Cox regression with adjustment for multiple predictors of death showed that patients in lower LA pressure tertiles had 59% lower mortality (P = 0.003). CONCLUSION: Lower LA pressure following mitral PVL closure is an independent predictor of improved survival, even after adjustment for residual MR. LA pressure monitoring may be a useful tool for procedural guidance during mitral PVL closure.

Multiparametric CMR imaging of infarct remodeling in a percutaneous reperfused Yucatan mini-pig model.

To further understanding of the temporal evolution and pathophysiology of adverse ventricular remodeling over the first 60 days following a myocardial infarction (MI) in both the infarcted and remote myocardium, we performed multi-parametric cardiac magnetic resonance (CMR) imaging in a closed-chest chronic Yucatan mini-pig model of reperfused MI. Ten animals underwent 90 min left anterior descending artery occlusion and reperfusion. Three animals served as controls. Multiparametric CMR (1.5T) was performed at baseline, Day 2, Day 30 and in four animals on Day 60 after MI. Left ventricular (LV) volumes and infarct size were measured. T1 and T2 mapping sequences were performed to measure values in the infarct and remote regions. Remote region collagen fractions were compared between infarcted animals and controls. Procedure success was 80%. The model created large infarcts (28 ± 5% of LV mass on Day 2), which led to significant adverse myocardial remodeling that stabilized beyond 30 days. Native T1 values did not reliably differentiate remote and infarct regions acutely. There was no evidence of remote fibrosis as indicated by partition coefficient and collagen fraction analyses. The infarct T2 values remained elevated up to 60 days after MI. Multiparametric CMR in this model showed significant adverse ventricular remodeling 30 days after MI similar to that seen in humans. In addition, this study demonstrated that remote fibrosis is absent and that infarct T2 signal remains chronically elevated in this model. These findings need to be considered when designing preclinical trials using CMR endpoints.

von Willebrand Factor Abnormalities and Heyde Syndrome in Dysfunctional Heart Valve Prostheses.

IMPORTANCE: Limited data suggest that von Willebrand factor (VWF) abnormalities may accompany the high-shear state associated with prosthetic valve dysfunction. If true, laboratory testing could add value in quantifying prosthesis dysfunction and could suggest a pathophysiological explanation for acquired bleeding in some patients. OBJECTIVES: To determine whether dysfunctional valve prostheses are associated with VWF abnormalities compared with normally functioning valve prostheses, to identify the severity of the VWF abnormality relative to other conditions, and to describe associated bleeding and the occurrence of gastrointestinal angiodysplasia. DESIGN, SETTING, AND PARTICIPANTS: Cohort study in a multispecialty practice setting from August 2010 through November 2015. To assess the severity of VWF dysfunction, data were compared with those from previously reported healthy controls and patients with aortic stenosis, mitral regurgitation, and left ventricular assist devices. Patients underwent assessment of multiple VWF laboratory tests and echocardiography. MAIN OUTCOMES AND MEASURES: Loss of high-molecular-weight multimers of VWF. RESULTS: A total of 136 patients were included in this study. During the study period, we assessed 26 patients with normally functioning surgical or transcatheter aortic valve replacement, 24 patients with dysfunctional aortic valve replacement, 36 patients with normally functioning mitral valve replacement or repair, 19 patients with dysfunctional mitral valve replacement or repair, and 31 patients with native aortic regurgitation without coexisting aortic stenosis. von Willebrand factor multimers were abnormal in 1 of 26 normal aortic valve replacements and in 2 of 36 normal mitral valve replacements or repairs but were abnormal in 20 of 24 dysfunctional aortic valve replacements and in 14 of 19 dysfunctional mitral valve replacements or repairs (P < .001 for both). Normal aortic valve replacement also had a higher VWF activity to antigen ratio, mean (range) 0.94 (0.84-0.99) compared to dysfunctional aortic valve replacement, 0.78 (0.73-0.87), P < .001, as did normal mitral valve replacement or repair, 0.90 (0.86-0.93) compared to dysfunctional mitral valve replacement or repair, 0.78 (0.70-0.90), P = .005. Platelet function analyzer closure times were lower with normal aortic valve replacement, mean (range) 92 (82-112) seconds compared to dysfunctional aortic valve replacement, 139 (122-177) seconds, P < .001, and also in normally functioning mitral valve replacement or repair, 85 (74-96) seconds compared to dysfunctional mitral valve replacement or repair, 143 (128-192) seconds, P < .001. Gastrointestinal bleeding was noted in 6 of 24 patients with aortic prosthesis dysfunction and in 5 of 19 patients with mitral prosthesis/repair dysfunction and was associated with a lower normalized VWF multimer ratio than in patients without bleeding. Gastrointestinal angiodysplasia was noted in 5 of 6 bleeding patients with dysfunctional aortic prostheses and in 3 of 5 bleeding patients with dysfunctional mitral prostheses/repair. CONCLUSIONS AND RELEVANCE: Acquired abnormalities of VWF multimers are associated with aortic and mitral prosthesis dysfunction, with occasional gastrointestinal bleeding and gastrointestinal angiodysplasia. Quantitative VWF tests may provide adjunctive value in the difficult assessment of prosthetic valve dysfunction.

Percutaneous Transvenous Transseptal Transcatheter Valve Implantation in Failed Bioprosthetic Mitral Valves, Ring Annuloplasty, and Severe Mitral Annular Calcification.

OBJECTIVES: This study sought to examine the feasibility, safety, and intermediate-term outcomes in patients undergoing percutaneous transvenous transcatheter mitral valve implantation in failed bioprosthesis, ring annuloplasty, and calcific mitral stenosis. BACKGROUND: Surgical mitral valve replacement in patients with previous surgery or severe mitral annular calcification (MAC) is often associated with high or prohibitive risk. METHODS: Percutaneous transfemoral antegrade transseptal implantation of Edwards SAPIEN prosthesis (Edwards Lifesciences, Irvine, California) was performed in 48 patients with degenerated mitral bioprosthesis (n = 33), previous ring annuloplasty (n = 9), and severe MAC (n = 6). RESULTS: The mean Society of Thoracic Surgeons risk score was 13.2 ± 7.4% with a mean age 76 ± 11 years. Acute procedural success was achieved in 42 of 48 patients (88%) in the overall group and 31 of 33 (94%) in the failed bioprosthetic mitral valve group and success rate of 11 of 15 (73%) in patients with failed annuloplasty rings and MAC. After successful procedure, no patients had > mild residual mitral prosthetic or periprosthetic regurgitation; mean transvalvular gradients were 6 ± 2.5 mm Hg. Thirty-day survival free of death and cardiovascular surgery was 85% in the overall group and 91% in the failed bioprosthetic mitral valve subgroup. CONCLUSIONS: Transfemoral percutaneous transvenous mitral valve implantation in high-risk patients with degenerated bioprosthesis is safe, effective, and associated with rapid improvement in hemodynamics, short length of stays, and improved functional status. Percutaneous mitral valve implantation in patients with failed annuloplasty rings and severe MAC is a promising therapy with significant short-term morbidity and mortality that requires further study.