Transcatheter Aortic-Valve Replacement with a Self-Expanding Valve in Low-Risk Patients.

BACKGROUND: Transcatheter aortic-valve replacement (TAVR) is an alternative to surgery in patients with severe aortic stenosis who are at increased risk for death from surgery; less is known about TAVR in low-risk patients. METHODS: We performed a randomized noninferiority trial in which TAVR with a self-expanding supraannular bioprosthesis was compared with surgical aortic-valve replacement in patients who had severe aortic stenosis and were at low surgical risk. When 850 patients had reached 12-month follow-up, we analyzed data regarding the primary end point, a composite of death or disabling stroke at 24 months, using Bayesian methods. RESULTS: Of the 1468 patients who underwent randomization, an attempted TAVR or surgical procedure was performed in 1403. The patients' mean age was 74 years. The 24-month estimated incidence of the primary end point was 5.3% in the TAVR group and 6.7% in the surgery group (difference, -1.4 percentage points; 95% Bayesian credible interval for difference, -4.9 to 2.1; posterior probability of noninferiority >0.999). At 30 days, patients who had undergone TAVR, as compared with surgery, had a lower incidence of disabling stroke (0.5% vs. 1.7%), bleeding complications (2.4% vs. 7.5%), acute kidney injury (0.9% vs. 2.8%), and atrial fibrillation (7.7% vs. 35.4%) and a higher incidence of moderate or severe aortic regurgitation (3.5% vs. 0.5%) and pacemaker implantation (17.4% vs. 6.1%). At 12 months, patients in the TAVR group had lower aortic-valve gradients than those in the surgery group (8.6 mm Hg vs. 11.2 mm Hg) and larger effective orifice areas (2.3 cm2 vs. 2.0 cm2). CONCLUSIONS: In patients with severe aortic stenosis who were at low surgical risk, TAVR with a self-expanding supraannular bioprosthesis was noninferior to surgery with respect to the composite end point of death or disabling stroke at 24 months. (Funded by Medtronic; ClinicalTrials.gov number, NCT02701283.).

Transcatheter aortic valve replacement for aortic insufficiency in a patient with aortic root Thrombus and left ventricular assist device: A risk worth taking?

A 61-year-old man with end-stage ischemic cardiomyopathy post HeartMate 3 (Abbott laboratories, Chicago, Illinois, USA) left ventricular assist device (LVAD) implant was hospitalized after he had recurrent ventricular tachycardia requiring implantable cardioverter-defibrillator shocks. His transthoracic echocardiogram and computed tomography angiography of the chest showed presence of trace aortic insufficiency (AI) and aortic root thrombus (ART) of non-coronary cusp without obstruction of right or left coronary artery ostium despite therapeutic international normalized ratio. He presented again 3 months later with worsening heart failure signs and symptoms. Transesophageal echocardiogram showed progression to severe AI and persistent ART. Despite hemodynamically guided LVAD speed optimization, inotropic support, and diuresis, the patient continued to deteriorate with worsening renal function. The patient was not a transplant candidate due to frailty. After multi-disciplinary discussion he underwent successful 29-Sapien S3 (Edwards Lifesciences, Irvine, CA, USA) transcatheter aortic valve replacement utilizing distal protection filters in bilateral internal carotid arteries for stroke prevention. This case provides novel insight to physicians treating LVAD patients regarding management of severe AI in the setting of ART. Learning objective: We report a rare approach employed for management of aortic insufficiency (AI) in a patient who also had an aortic root thrombus and left ventricular assist device (LVAD) that traditionally requires cardiac transplantation. Our patient had a favorable outcome with a minimally invasive transcatheter aortic valve replacement. With this case, we hope to generate awareness amongst physicians treating patients about management alternatives and approach of a commonly encountered, life-threatening complication of AI in patients with LVAD.

Hybrid repair of acute type B dissection with aberrant right subclavian artery and bicarotid trunk.

Patients with type B aortic dissection (TBAD) often present as an emergency. Operative repair of TBAD can be indicated for selected patients in the setting of hemodynamic instability or rupture. Thoracic endovascular aortic repair of TBAD has achieved significant popularity. Variant aortic arch anatomy can present a significant clinical challenge in patients with an inadequate proximal landing zone for thoracic endovascular aortic repair. A three-stage, hybrid aortic arch debranching and endovascular repair of a ruptured TBAD in a patient with a bicarotid trunk and an aberrant right subclavian artery was successfully performed using a unique technical approach.

Prophylactic Left Atrial Appendage Exclusion in Cardiac Surgery Patients With Elevated CHA2DS2-VASc Score: Results of the Randomized ATLAS Trial.

OBJECTIVE: Patients with elevated CHA2DS2-VASc scores are at high risk for atrial fibrillation (AF) and thromboembolic events (TE) after cardiac surgery. Left atrial appendage exclusion (LAAE) is a permanent, continuous approach to stroke prevention in AF, overcoming limitations of oral anticoagulation (OAC). We report ATLAS trial results focused on LAAE technical success and perioperative safety and TE rates with and without LAAE in cardiac surgery patients who developed postoperative AF (POAF). METHODS: ATLAS (NCT02701062) was a prospective, multicenter, feasibility trial. Patients age ≥18 years, undergoing structural heart procedure, with no preoperative AF, CHA2DS2-VASc ≥2, and HAS-BLED ≥2 were randomized 2:1 to LAAE or no LAAE. Patients who developed POAF and/or received LAAE were followed for 1 year. LAAE was evaluated with intraoperative transesophageal echocardiography. RESULTS: A total of 562 patients were randomized to LAAE (n = 376) or no LAAE (n = 186). Mean CHA2DS2-VASc (3.4 vs 3.4) and HAS-BLED (2.8 vs 2.9) scores were similar for LAAE and no LAAE groups. LAAE success (no flow nor residual stump >10 mm) was 99%. One LAAE-related serious adverse event (0.27%) occurred and was resolved without sequelae. There were 44.3% of patients who developed POAF. Through 1 year, 3.4% of LAAE patients and 5.6% of no LAAE patients had TE. OAC was used by 32.5% of POAF patients. Bleeding was higher with OAC than without (16.1% vs 5.4%, P = 0.008). CONCLUSIONS: ATLAS demonstrated a high rate of successful LAAE with low LAAE-related serious adverse events in cardiac surgery patients. Study results should be considered in future trial design to further evaluate prophylactic LAAE for stroke prevention in cardiac surgery patients with elevated stroke risk.

2-Year Outcomes After Transcatheter Versus Surgical Aortic Valve Replacement in Low-Risk Patients.

BACKGROUND: The Evolut Low Risk Trial (Medtronic Evolut Transcatheter Aortic Valve Replacement in Low Risk Patients) showed that transcatheter aortic valve replacement (TAVR) with a supra-annular, self-expanding valve was noninferior to surgery for the primary endpoint of all-cause mortality or disabling stroke at 2 years. This finding was based on a Bayesian analysis performed after 850 patients had reached 1 year of follow-up. OBJECTIVES: The goal of this study was to report the full 2-year clinical and echocardiographic outcomes for patients enrolled in the Evolut Low Risk Trial. METHODS: A total of 1,414 low-surgical risk patients with severe aortic stenosis were randomized to receive TAVR or surgical AVR. An independent clinical events committee adjudicated adverse events, and a central echocardiographic core laboratory assessed hemodynamic endpoints. RESULTS: An attempted implant was performed in 730 TAVR and 684 surgical patients from March 2016 to May 2019. The Kaplan-Meier rates for the complete 2-year primary endpoint of death or disabling stroke were 4.3% in the TAVR group and 6.3% in the surgery group (P = 0.084). These rates were comparable to the interim Bayesian rates of 5.3% with TAVR and 6.7% with surgery (difference: -1.4%; 95% Bayesian credible interval: -4.9% to 2.1%). All-cause mortality rates were 3.5% vs 4.4% (P = 0.366), and disabling stroke rates were 1.5% vs 2.7% (P = 0.119), respectively. Between years 1 and 2, there was no convergence of the primary outcome curves. CONCLUSIONS: The complete 2-year follow-up from the Evolut Low Risk Trial found that TAVR is noninferior to surgery for the primary endpoint of all-cause mortality or disabling stroke, with event rates that were slightly better than those predicted by using the Bayesian analysis. (Medtronic Evolut Transcatheter Aortic Valve Replacement in Low Risk Patients [Evolut Low Risk Trial]; NCT02701283).

The Impact of Transfusions on Mortality After Transcatheter or Surgical Aortic Valve Replacement.

BACKGROUND: An increasing body of evidence suggests that packed red blood cell (PRBC) transfusion may be associated with increased morbidity and mortality after transcatheter and surgical aortic valve replacement. It remains unclear whether PRBC transfusion is a surrogate marker or truly an independent risk factor for mortality after aortic valve replacement in different populations. METHODS: The Surgical Replacement and Transcatheter Aortic Valve Implantation (SURTAVI) trial randomized 1660 patients with symptomatic, severe aortic stenosis at intermediate risk for operative death to transcatheter aortic valve replacement or surgical aortic valve replacement. Baseline characteristics and outcomes including all-cause and cardiovascular mortality at 30 days and thereafter were compared between participants with and participants without PRBC transfusion. Cox proportional hazards models with time-varying covariates were fitted to estimate the effect of PRBC transfusion on mortality after adjustment for comorbidities and procedural complications. RESULTS: Patients receiving PRBC were older, more commonly female and frail, with more comorbidities. The Society of Thoracic Surgeons Predicted Risk of Mortality baseline score was higher in the transfused group. After adjustment for these differences, PRBC transfusion was associated with mortality at 30 days, but not thereafter. The effect of PRBC on mortality (hazard ratio 1.04; 95% confidence interval, 0.96 to 1.11; P = .304) at 30 days was not independent of procedural complications (hazard ratio 21.04; 95% CI, 7.26 to 60.95; P < .001). CONCLUSIONS: Poor health status, procedural complications, PRBC transfusion, and mortality are correlated with each other. Transfusion of PRBC did not independently increase risk for mortality. In this intermediate-risk population, transfusion appears to be a risk marker of chronic conditions and periprocedural complications as opposed to a risk factor for postprocedural mortality. (Clinical trial registration: www.clinicaltrials.gov NCT01586910.).

Three-Year Outcomes With a Contemporary Self-Expanding Transcatheter Valve From the Evolut PRO US Clinical Study.

BACKGROUND: Paravalvular regurgitation (PVR) following transcatheter aortic valve replacement (TAVR) is associated with increased morbidity and mortality. PVR continues to plague TAVR jeopardizing long-term results. New device iterations, such as the self-expandable Evolut PRO valve, aim to decrease PVR while maintaining optimal hemodynamics. This study sought to evaluate clinical and hemodynamic performance of the Evolut PRO system at 3 years. METHODS: The Evolut PRO US Clinical Study included 60 patients at high or extreme surgical risk undergoing TAVR with the Evolut PRO valve at 8 centers in the United States. Clinical outcomes were evaluated using Valve Academic Research Consortium (VARC)-2 criteria and included all-cause mortality, cardiovascular mortality, disabling stroke and valve complications. An independent core laboratory centrally assessed all echocardiographic measures. RESULTS: At 3 years, all-cause mortality was 25.8% (cardiovascular mortality 16.5%) and the disabling stroke rate was 10.7%. There were no cases of repeat valve intervention, endocarditis or coronary obstruction. Valve thrombosis was identified in 1 patient 2 years post-procedure and was treated medically. Hemodynamics at 3 years included a mean gradient of 7.2 ± 4.5 mm Hg, an effective orifice area of 2.0 ± 0.5 cm2, and 88.2% of patients had no or trace PVR. The remaining patients had mild PVR. Most of the surviving patients (80.6%) had New York Heart Association class I symptoms at 3 years. CONCLUSION: Outcomes at 3-years following TAVR with a contemporary self-expanding prosthesis are favorable, with no signal of valve deterioration, excellent hemodynamics including very low prevalence of PVR.

Subclavian/Axillary Access for Self-Expanding Transcatheter Aortic Valve Replacement Renders Equivalent Outcomes as Transfemoral.

BACKGROUND: Iliofemoral arterial disease can preclude transfemoral (TF) transcatheter aortic valve replacement (TF-TAVR). Transthoracic access by direct aortic or a transapical approach imparts a greater risk of complications and death than TF access. We hypothesized that subclavian/axillary arterial (SCA) access offers equivalent risks and outcomes as TF access. METHODS: The outcomes of 202 patients from the CoreValve (Medtronic, Minneapolis, MN) United States Pivotal Trial Program treated with SCA access were propensity matched with patients treated with TF access and analyzed. RESULTS: Matching was successful, with no significant baseline differences in the SCA group and the TF group, except the SCA group had more past or present smokers (79.2% vs 61.4%, p < 0.001) and fewer patients with anemia requiring transfusion (18.5% vs 27.5%, p = 0.04). SCA patients experienced a significantly longer time from enrollment to procedure (8.6 ± 19.1 vs 5.3 ± 6.3 days; p = 0.02), likely the result of case planning. Significant differences in procedural outcomes include less post-TAVR balloon dilation (17.9% vs 26.7%, p = 0.03) and more general anesthesia (99.0% vs 89.6%, p < 0.001) for the SCA accesses. There were no differences in procedure time (57.8 ± 45.3 vs 57.5 ± 32.1 min, p = 0.94) or Valve Academic Research Consortium I-defined procedure success between groups (p = 0.89). Event rates at 30 days or 1 year were similar, with a trend toward fewer pacemakers with SCA accesses. CONCLUSIONS: Major morbidity and mortality rates SCA-TAVR are equivalent to TF-TAVR. The SCA should be the preferred secondary access site for TAVR because it offers procedural and clinical outcomes comparable to TF-TAVR and applies to most patients who are not TF candidates.

Impact of Annular Size on Outcomes After Surgical or Transcatheter Aortic Valve Replacement.

BACKGROUND: This analysis evaluates the relationship of annular size to hemodynamics and the incidence of prosthesis-patient mismatch (PPM) in surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) patients. METHODS: The CoreValve US Pivotal High Risk Trial, described previously, compared TAVR using a self-expanding valve with SAVR. Multislice computed tomography was used to categorize TAVR and SAVR subjects according to annular perimeter-derived diameter: large (≥26 mm), medium (23 to <26 mm), and small (<23 mm). Hemodynamics, PPM, and clinical outcomes were assessed. RESULTS: At all postprocedure visits, mean gradients were significantly lower for TAVR compared with SAVR in small and medium size annuli (p < 0.001). Annular size was significantly associated with mean gradient after SAVR, with small annuli having the highest gradients (p < 0.05 at all timepoints); gradients were similar across all annular sizes after TAVR. In subjects receiving SAVR, the frequency of PPM was significantly associated with annular size, with small annuli having the greatest incidence. No difference in PPM incidence by annular sizing was observed with TAVR. In addition, TAVR subjects had significantly less PPM than SAVR subjects in small and medium annuli (p < 0.001), with no difference in the incidence of PPM between TAVR and SAVR in large annuli (p = 0.10). CONCLUSIONS: Annular size has a significant effect on hemodynamics and the incidence of PPM in SAVR subjects, not observed in TAVR subjects. With respect to annular size, TAVR results in better hemodynamics and less PPM for annuli less than 26 mm and should be strongly considered when choosing a tissue valve for small and medium size annuli.

Early Outcomes With the Evolut PRO Repositionable Self-Expanding Transcatheter Aortic Valve With Pericardial Wrap.

OBJECTIVES: This study sought to evaluate the Medtronic Evolut PRO Transcatheter Aortic Valve System in patients with severe symptomatic aortic stenosis. BACKGROUND: A next-generation self-expanding transcatheter aortic valve was designed with an external pericardial wrap with the intent to reduce paravalvular leak while maintaining the benefits of a low-profile, self-expanding, and repositionable supra-annular valve. METHODS: The Medtronic Evolut PRO Clinical Study included 60 patients undergoing transcatheter aortic valve replacement with the Evolut PRO valve at 8 investigational sites in the United States. Clinical outcomes at 30 days were evaluated using Valve Academic Research Consortium-2 criteria. The 2 primary safety endpoints were the incidence of all-cause mortality at 30 days and the incidence of disabling stroke at 30 days. The primary efficacy endpoint was the proportion of patients with no or trace prosthetic valve regurgitation at 30 days. An independent echocardiographic core laboratory (Mayo Clinic, Rochester, Minnesota) was used to adjudicate all echocardiographic assessments. RESULTS: All 60 patients received the Evolut PRO valve. At 30 days, 1 patient (1.7%) died and 1 patient (1.7%) experienced a nonfatal disabling stroke. Paravalvular regurgitation at 30 days was absent or trace in 72.4% of patients and was mild in the remainder of patients, with no patients having worse than mild paravavlular leak. The mean atrioventricular gradient was 6.4 ± 2.1 mm Hg and effective orifice area was 2.0 ± 0.5 cm2 at 30 days. CONCLUSIONS: The safety and efficacy results of this study support the use of the Evolut PRO System for the treatment of severe symptomatic aortic stenosis in patients who are at increased surgical risk, resulting in excellent hemodynamics and minimal paravalvular leak (The Medtronic TAVR 2.0 US Clinical Study; NCT02738853).

5-Year Outcomes of Self-Expanding Transcatheter Versus Surgical Aortic Valve Replacement in High-Risk Patients.

BACKGROUND: The CoreValve U.S. Pivotal High Risk Trial was the first randomized trial to show superior 1-year mortality of transcatheter aortic valve replacement (TAVR) compared with surgical aortic valve replacement (SAVR) among high operative mortality-risk patients. OBJECTIVES: The authors sought to compare TAVR to SAVR for mid-term 5-year outcomes of safety, performance, and durability. METHODS: Surgical high-risk patients were randomized (1:1) to TAVR with the self-expanding bioprosthesis or SAVR. VARC-1 (Valve Academic Research Consortium I) definitions were applied. Severe hemodynamic structural valve deterioration was defined as a mean gradient ≥40 mm Hg or a change in gradient ≥20 mm Hg or new severe aortic regurgitation. Five-year follow-up was planned. RESULTS: A total of 797 patients were randomized at 45 U.S. centers, of whom 750 underwent an attempted implant (TAVR = 391, SAVR = 359). The overall mean age was 83 years, and the STS score was 7.4%. All-cause mortality rates at 5 years were 55.3% for TAVR and 55.4% for SAVR. Subgroup analysis showed no differences in mortality. Major stroke rates were 12.3% for TAVR and 13.2% for SAVR. Mean aortic valve gradients were 7.1 ± 3.6 mm Hg for TAVR and 10.9 ± 5.7 mm Hg for SAVR. No clinically significant valve thrombosis was observed. Freedom from severe SVD was 99.2% for TAVR and 98.3% for SAVR (p = 0.32), and freedom from valve reintervention was 97.0% for TAVR and 98.9% for SAVR (p = 0.04). A permanent pacemaker was implanted in 33.0% of TAVR and 19.8% of SAVR patients at 5 years. CONCLUSIONS: This study shows similar mid-term survival and stroke rates in high-risk patients following TAVR or SAVR. Severe structural valve deterioration and valve reinterventions were uncommon. (Safety and Efficacy Study of the Medtronic CoreValve® System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902).

Complications After Self-expanding Transcatheter or Surgical Aortic Valve Replacement.

Procedural complications following transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) are usually reported as retrospective analyses. We report the first comparison of complications following SAVR or self-expanding TAVR from a prospectively randomized study of high-risk SAVR patients. Three hundred ninety-five TAVR and 402 SAVR patients were prospectively enrolled and randomized 1:1 to TAVR with a CoreValve bioprosthesis or a surgical bioprosthetic valve. The rates of major procedural and vascular complications occurring (periprocedurally (0-3 days) and early (4-30 days)) were compared for TAVR vs SAVR patients. All-cause mortality, stroke, myocardial infarction, and major infection were similar in both periods post procedure. Within 0-3 days, the major vascular complication rate was significantly higher with TAVR (P = 0.003). Life-threatening or disabling bleeding (P < 0.001), encephalopathy (P = 0.02), atrial fibrillation (P < 0.001), and acute kidney injury (P < 0.001) were significantly higher with SAVR. Non-iliofemoral TAVR approaches had a higher incidence of major or life-threatening or disabling bleeding at 0-3days (P < 0.05). Procedural complications unique to TAVR included coronary occlusion 0.5% (2) and TAVR pop outs 2.8% (11) with no valve embolizations. Pop outs were similar between iliofemoral 2.8% (9/324) and non-iliofemoral approaches 3.0% (2/66). Procedural complications unique to SAVR included aortic dissection 0.8% (3/357) and injury to other heart structures 2.0% (7/357). The procedural complication profiles of TAVR and SAVR are unique. Intraoperative deaths were seen in TAVR only. Mortality at 3 and 30 days was similar. The higher incidence of some complications likely reflects the greater invasiveness of SAVR in this aged high-risk population.

Causes of death from the randomized CoreValve US Pivotal High-Risk Trial.

OBJECTIVE: Explore causes and timing of death from the CoreValve US Pivotal High-Risk Trial. METHODS: An independent clinical events committee adjudicated causes of death, followed by post hoc hierarchical classification. Baseline characteristics, early outcomes, and causes of death were evaluated for 3 time periods (selected based on threshold of surgical 30-day mortality and on the differences in the continuous hazard between the 2 groups): early (0-30 days), recovery (31-120 days), and late (121-365 days). RESULTS: Differences in the rate of death were evident only during the recovery period (31-120 days), whereas 15 patients undergoing transcatheter aortic valve replacement (TAVR) (4.0%) and 27 surgical aortic valve replacement (SAVR) patients (7.9%) died (P = .025). This mortality difference was largely driven by higher rates of technical failure, surgical complications, and lack of recovery following surgery. From 0 to 30 days, the causes of death were more technical failures in the TAVR group and lack of recovery in the SAVR group. Mortality in the late period (121-365 days) in both arms was most commonly ascribed to other circumstances, comprising death from medical complications from comorbid disease. CONCLUSIONS: Mortality at 1 year in the CoreValve US Pivotal High-Risk Trial favored TAVR over SAVR. The major contributor was that more SAVR patients died during the recovery period (31-121 days), likely affected by the overall influence of physical stress associated with surgery. Similar rates of technical failure and complications were observed between the 2 groups. This suggests that early TAVR results can improve with technical refinements and that high-risk surgical patients will benefit from reducing complications.

Alloimmunity in primate heart recipients with CD154 blockade: evidence for alternative costimulation mechanisms.

BACKGROUND: CD154 mediates key facets of humoral and cellular immunity to alloantigens, and is tolerogenic to influenza antigens in primates. Barriers to CD154-based tolerance induction for primate cardiac allografts have not previously been defined. METHODS: Heterotopic cardiac allograft outcomes in cynomolgus monkeys treated with a CD154 inhibitor, IDEC-131 (n=27), were compared to no treatment (n=4) or cyclosporine A (n=6). RESULTS: CD154 blockade significantly prolonged median allograft survival, from 6.2 (range 6, 7, n=4) days in untreated controls, to 39 (8,112, n=16) days with intensive monotherapy and 93 (>25, 386; n=3) days with added antithymocyte globulin (ATG), but did not yield tolerance. Alloantibody production was delayed but not prevented by IDEC-131 alone or with ATG, and was exacerbated by infusion of donor bone marrow (n=8). Expression of ICOS was prominent in graft infiltrating lymphocytes, and preceded elaboration of antidonor antibody and vasculopathy. CONCLUSION: CD154 monotherapy modulates primate cardiac alloimmunity, but does not readily induce tolerance. Targeting alternative costimulation pathways, including ICOS, may facilitate tolerance induction based on CD154 blockade.

Transcatheter or Surgical Aortic Valve Replacement in Patients With Prior Coronary Artery Bypass Grafting.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) are treatment options for aortic stenosis in patients with prior coronary artery bypass graft surgery. We assessed the major clinical outcomes of such patients enrolled in the CoreValve High Risk (CHR) study. METHODS: Of the 795 CHR study patients, 226 had prior coronary artery bypass graft surgery; 115 underwent TAVR and 111 underwent SAVR. The primary endpoint was a comparison of all-cause mortality at 1 year. Important secondary clinical endpoints were assessed. RESULTS: At 1 year, all-cause mortality was 9.6% for TAVR versus 18.1% for SAVR (p = 0.06); cardiovascular mortality was 7.0% for TAVR versus 13.8% for SAVR (p = 0.09). A combination of The Society of Thoracic Surgeons risk score greater than 7 and age greater than 80 years was a significant predictor of mortality, with TAVR demonstrating a survival advantage (p = 0.03). No differences were seen for stroke. The SAVR group had longer intensive care unit and hospital stays, increased incidence of acute kidney injury, life-threatening or disabling bleeding, and major adverse cardiac and cerebrovascular events (p < 0.05). Pacemaker implantation and paravalvular regurgitation were greater with TAVR at all timepoints. CONCLUSIONS: For patients with prior coronary artery bypass graft surgery and aortic stenosis, TAVR offers a significant morbidity advantage and a strong trend toward improved survival over SAVR at 1 year.

Prosthesis-patient mismatch in high-risk patients with severe aortic stenosis: A randomized trial of a self-expanding prosthesis.

OBJECTIVES: We compared the incidence of prosthesis-patient mismatch (PPM) between transcatheter aortic valve replacement (TAVR) using a self-expanding bioprosthesis and surgical aortic valve replacement (SAVR) in the CoreValve US High Risk Pivotal Trial. We sought to determine the influence of PPM on clinical outcomes. METHODS: Patients with severe aortic stenosis and at increased risk for surgery were randomized 1:1 to TAVR or SAVR. Postoperative PPM was defined by the effective orifice area index (EOAi) as severe PPM (EOAi ≤ 0.65 cm(2)/m(2)) and no severe PPM (EOAi > 0.65 cm(2)/m(2)); clinical outcomes were analyzed in the TAVR arm (n = 389) and SAVR arm (n = 353). Left ventricular mass index and regression were analyzed at baseline and 1 year. RESULTS: The incidence of severe PPM in the SAVR group at 1 year was 25.7% versus 6.2% in the TAVR group (P < .0001). Left ventricular mass index regression at 1 year was 6.8% for TAVR and 15.1% for SAVR in patients with severe PPM. At 1 year the rate of all-cause mortality and acute kidney injury were significantly greater in all patients (TAVR + SAVR) with severe PPM compared with no severe PPM (20.6% vs 12.0% [P = .0145] for death and 19.2% vs 8.5% [P = .0008] for acute kidney injury). CONCLUSIONS: In patients with high surgical risk and severe aortic stenosis, severe PPM is more common in patients treated with SAVR than those treated with TAVR. Patients with severe PPM are a greater risk for death and acute kidney injury than patients without severe PPM.

Self-Expanding Transcatheter Aortic Valve Replacement Versus Surgical Valve Replacement in Patients at High Risk for Surgery: A Study of Echocardiographic Change and Risk Prediction.

BACKGROUND: The CoreValve US High-Risk Clinical Study compared clinical outcomes and serial echocardiographic findings in patients with severe aortic valve stenosis after transcatheter aortic valve replacement (TAVR) with a self-expanding bioprosthesis or surgical aortic valve replacement (SAVR). METHODS AND RESULTS: Eligible patients were randomly assigned 1:1 to TAVR with a self-expanding bioprosthesis or SAVR (N=747). Echocardiograms were obtained at baseline, discharge, 30 days, 6 months, and 1 year after the procedure and were analyzed at a central core laboratory. Compared with SAVR patients (N=357), TAVR patients (N=390) had a lower mean aortic valve gradient, larger valve area, and less patient-prosthesis mismatch (all P<0.001), but more paravalvular regurgitation at discharge, which decreased at 1 year. SAVR patients experienced significant right ventricular systolic dysfunction at discharge and 1 month with normal right ventricular function at 1 year. One-year all-cause mortality was 14.2% for TAVR and 19.1% for SAVR patients. Preimplantation aortic regurgitation ≥mild was associated with reduced mortality hazard for both the TAVR (hazard ratio 0.48, 95% confidence interval 0.27-0.85; P=0.01) and the SAVR groups (hazard ratio 0.53, 95% confidence interval 0.32-0.87; P=0.01). Aortic regurgitation ≥mild after TAVR was associated with increased risk for all-cause mortality (hazard ratio 1.95, 95% confidence interval 1.08-3.53; P=0.03). CONCLUSIONS: In patients with severe aortic stenosis at increased surgical risk, TAVR was associated with better systolic valve performance, similar left ventricular remodeling, more paravalvular regurgitation, and less right ventricular systolic dysfunction compared with SAVR. Despite an overall mortality reduction for the TAVR group, ≥mild aortic valve regurgitation after TAVR was associated with an increased mortality hazard. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01240902.

3-Year Outcomes in High-Risk Patients Who Underwent Surgical or Transcatheter Aortic Valve Replacement.

BACKGROUND: In patients with severe aortic stenosis at increased risk for surgery, self-expanding transcatheter aortic valve replacement (TAVR) is associated with improved 2-year survival compared with surgery. OBJECTIVES: This study sought to determine whether this clinical benefit was sustained over time. METHODS: Patients with severe aortic stenosis deemed at increased risk for surgery by a multidisciplinary heart team were randomized 1:1 to TAVR or open surgical valve replacement (SAVR). Three-year clinical and echocardiographic outcomes were obtained in those patients with an attempted procedure. RESULTS: A total of 797 patients underwent randomization at 45 U.S. centers; 750 patients underwent an attempted procedure. Three-year all-cause mortality or stroke was significantly lower in TAVR patients (37.3% vs. 46.7% in SAVR; p = 0.006). Adverse clinical outcome components were also reduced in TAVR patients compared with SAVR patients, including all-cause mortality (32.9% vs. 39.1%, respectively; p = 0.068), all stroke (12.6% vs. 19.0%, respectively; p = 0.034), and major adverse cardiovascular or cerebrovascular events (40.2% vs. 47.9%, respectively; p = 0.025). At 3 years aortic valve hemodynamics were better with TAVR patients (mean aortic valve gradient 7.62 ± 3.57 mm Hg vs. 11.40 ± 6.81 mm Hg in SAVR; p < 0.001), although moderate or severe residual aortic regurgitation was higher in TAVR patients (6.8% vs. 0.0% in SAVR; p < 0.001). There was no clinical evidence of valve thrombosis in either group. CONCLUSIONS: Patients with severe aortic stenosis at increased risk for surgery had improved 3-year clinical outcomes after TAVR compared with surgery. Aortic valve hemodynamics were more favorable in TAVR patients without differences in structural valve deterioration. (Safety and Efficacy Study of the Medtronic CoreValve(®) System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902).

Outcomes in the Randomized CoreValve US Pivotal High Risk Trial in Patients With a Society of Thoracic Surgeons Risk Score of 7% or Less.

Importance: Transcatheter aortic valve replacement (TAVR) is now a well-accepted alternative to surgical AVR (SAVR) for patients with symptomatic aortic stenosis at increased operative risk. There is interest in whether TAVR would benefit patients at lower risk. Objective: The Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) has trended downward in US TAVR trials and the STS/American College of Cardiology Transcatheter Valve Therapy Registry. We hypothesized that if the Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) alone is sufficient to define decreased risk, the contribution to survival based on the degree of invasiveness of the TAVR procedure will decrease, making it more difficult to show improved survival and benefit over SAVR. Design, Setting, and Participants: The CoreValve US Pivotal High Risk Trial was a multicenter, randomized, noninferiority trial. This retrospective analysis evaluated patients who underwent an attempted implant and had an STS PROM of 7% or less. The trial was performed at 45 US sites. Patients had severe aortic stenosis and were at increased surgical risk based on their STS PROM score and other risk factors. Interventions: Eligible patients were randomly assigned (1:1) to self-expanding TAVR or to SAVR. Main Outcomes and Measures: We retrospectively stratified patients by the overall median STS PROM score (7%) and analyzed clinical outcomes and quality of life using the Kansas City Cardiomyopathy Questionnaire in patients with an STS PROM score of 7% or less. Results: The mean (SD) ages were 81.5 (7.6) years for the TAVR group and 81.2 years (6.6) for the SAVR group. A little more than half were men (57.9% in the TAVR group and 55.8% in the SAVR group). Of 750 patients who underwent attempted implantation, 383 (202 TAVR and 181 SAVR) had an STS PROM of 7% or less (median [interquartile range]: TAVR, 5.3% [4.3%-6.1%]; SAVR, 5.3% [4.1%-5.9%]). Two-year all-cause mortality for TAVR vs SAVR was 15.0% (95% CI, 8.9-10.0) vs 26.3% (95% CI, 19.7-33.0) (log rank P = .01). The 2-year rate of stroke for TAVR vs SAVR was 11.3% vs 15.1% (log rank P = .50). Quality of life by the Kansas City Cardiomyopathy Questionnaire summary score showed significant and equivalent increases in both groups at 2 years (mean [SD] TAVR, 20.0 [25.0]; SAVR, 18.6 [23.6]; P = .71; both P < .001 compared with baseline). Medical benefit, defined as alive with a Kansas City Cardiomyopathy Questionnaire summary score of at least 60 and a less than 10-point decrease from baseline, was similar between groups at 2 years (TAVR, 51.0%; SAVR, 44.4%; P = .28). Conclusions and Relevance: Self-expanding TAVR compares favorably with SAVR in high-risk patients with STS PROM scores traditionally considered intermediate risk. Trial Registration: Clinicaltrials.gov Identifier: NCT01240902.

Hyperacute lung rejection in the pig-to-human model 4: evidence for complement and antibody independent mechanisms.

BACKGROUND: We assessed whether the combination of complement regulation and depletion of xenoreactive antibodies improves the outcome of pulmonary xenografts compared with either strategy alone. METHODS: Lungs from pigs heterozygous (hDAF(+/-)) or homozygous (hDAF(+/+)) for the human decay accelerating factor transgene (hDAF) or their nontransgenic litter mates (hDAF(-/-)) were perfused with heparinized whole human blood. In additional groups, xenoreactive natural antibodies (XNA) were depleted by pig lung perfusion (hDAF(-/-)/AbAbs, hDAF(+/-)/AbAbs) before the experiment. This combined approach was augmented by adding soluble complement receptor 1 (sCR1) to the perfusate in one further group (hDAF(+/-)/AbAbs/sCR1). RESULTS: HDAF(-/-) lungs perfused with unmodified human blood were rejected after 32.5 min (interquartile range, IQR 5 to 210). HDAF(+/-) lungs survived for 90 min (IQR 10 to 161, P = 0.54). Both groups showed a rapid rise in pulmonary vascular resistance (PVR), which is a characteristic feature of hyperacute rejection (HAR). This phenomenon was blunted in the hDAF(+/+) group, although survival (48 min, IQR 14 to 111) was not further prolonged. Antibody depletion (AbAbs) led to a significant increase in survival time (hDAF(-/-)/AbAbs: 315 min, IQR 230 to 427; hDAF(+/-)/AbAbs: 375 min, IQR 154 to 575), reduced PVR and less complement production. Addition of sCR1 reduced complement elaboration but did not further improve survival (200 min, IQR 128 to 580) and surprisingly tended to increase PVR. CONCLUSIONS: Depletion of xenoreactive antibodies is more effective than membrane-bound complement regulation to blunt hyperacute rejection of pulmonary xenografts, but even the combined approach including soluble-phase complement inhibition is not sufficient to reliably prevent organ failure within hours. It therefore seems likely that other factors independent of antibody and complement contribute to HAR in this model.