Samir Kapadia

Transcatheter versus Surgical Aortic-Valve Replacement in High-Risk Patients

BACKGROUND The use of transcatheter aortic-valve replacement has been shown to reduce mortality among high-risk patients with aortic stenosis who are not candidates for surgical replacement. However, the two procedures have not been compared in a randomized trial involving high-risk patients who are still candidates for surgical replacement. METHODS At 25 centers, we randomly assigned 699 high-risk patients with severe aortic stenosis to undergo either transcatheter aortic-valve replacement with a balloon-expandable bovine pericardial valve (either a transfemoral or a transapical approach) or surgical replacement. The primary end point was death from any cause at 1 year. The primary hypothesis was that transcatheter replacement is not inferior to surgical replacement. RESULTS The rates of death from any cause were 3.4% in the transcatheter group and 6.5% in the surgical group at 30 days (P=0.07) and 24.2% and 26.8%, respectively, at 1 year (P=0.44), a reduction of 2.6 percentage points in the transcatheter group (upper limit of the 95% confidence interval, 3.0 percentage points; predefined margin, 7.5 percentage points; P=0.001 for noninferiority). The rates of major stroke were 3.8% in the transcatheter group and 2.1% in the surgical group at 30 days (P=0.20) and 5.1% and 2.4%, respectively, at 1 year (P=0.07). At 30 days, major vascular complications were significantly more frequent with transcatheter replacement (11.0% vs. 3.2%, P<0.001); adverse events that were more frequent after surgical replacement included major bleeding (9.3% vs. 19.5%, P<0.001) and new-onset atrial fibrillation (8.6% vs. 16.0%, P=0.006). More patients undergoing transcatheter replacement had an improvement in symptoms at 30 days, but by 1 year, there was not a significant between-group difference. CONCLUSIONS In high-risk patients with severe aortic stenosis, transcatheter and surgical procedures for aortic-valve replacement were associated with similar rates of survival at 1 year, although there were important differences in periprocedural risks. (Funded by Edwards Lifesciences; Clinical Trials.gov number, NCT00530894.).

Transcatheter or Surgical Aortic-Valve Replacement in Intermediate-Risk Patients

BACKGROUND Previous trials have shown that among high-risk patients with aortic stenosis, survival rates are similar with transcatheter aortic-valve replacement (TAVR) and surgical aortic-valve replacement. We evaluated the two procedures in a randomized trial involving intermediate-risk patients. METHODS We randomly assigned 2032 intermediate-risk patients with severe aortic stenosis, at 57 centers, to undergo either TAVR or surgical replacement. The primary end point was death from any cause or disabling stroke at 2 years. The primary hypothesis was that TAVR would not be inferior to surgical replacement. Before randomization, patients were entered into one of two cohorts on the basis of clinical and imaging findings; 76.3% of the patients were included in the transfemoral-access cohort and 23.7% in the transthoracic-access cohort. RESULTS The rate of death from any cause or disabling stroke was similar in the TAVR group and the surgery group (P=0.001 for noninferiority). At 2 years, the Kaplan-Meier event rates were 19.3% in the TAVR group and 21.1% in the surgery group (hazard ratio in the TAVR group, 0.89; 95% confidence interval [CI], 0.73 to 1.09; P=0.25). In the transfemoral-access cohort, TAVR resulted in a lower rate of death or disabling stroke than surgery (hazard ratio, 0.79; 95% CI, 0.62 to 1.00; P=0.05), whereas in the transthoracic-access cohort, outcomes were similar in the two groups. TAVR resulted in larger aortic-valve areas than did surgery and also resulted in lower rates of acute kidney injury, severe bleeding, and new-onset atrial fibrillation; surgery resulted in fewer major vascular complications and less paravalvular aortic regurgitation. CONCLUSIONS In intermediate-risk patients, TAVR was similar to surgical aortic-valve replacement with respect to the primary end point of death or disabling stroke. (Funded by Edwards Lifesciences; PARTNER 2 ClinicalTrials.gov number, NCT01314313.).

Tumor Necrosis Factor-α and Tumor Necrosis Factor Receptors in the Failing Human Heart

Background Tumor necrosis factor-α (TNF-α) is a proinflammatory cytokine that produces negative inotropic effects in the heart. Recently, elevated levels of TNF-α have been reported in patients with advanced congestive heart failure. Although TNF-α is thought to exert its deleterious effects by binding to two cell surface receptors, TNFR1 and TNFR2, the level of expression and regulation of TNF receptors in the heart in cardiac disease states is not known. Methods and Results We examined mRNA and protein levels for TNFR1, TNFR2, and TNF-α in explanted hearts from organ donors as well as in patients with end-stage dilated cardiomyopathy (DCM) and ischemic heart disease (IHD). Northern blot analysis revealed that mRNA for TNFR1 and TNFR2 was present in nonfailing, DCM, and IHD hearts. TNFR1 and TNFR2 receptor protein levels, as measured by ELISA, were decreased 60% in DCM and IHD patients compared with nonfailing hearts (P<.005). To determine a potential mechanism for the decrease in TNF receptor expression...

Transcatheter Aortic-Valve Replacement for Inoperable Severe Aortic Stenosis

BACKGROUND Transcatheter aortic-valve replacement (TAVR) is the recommended therapy for patients with severe aortic stenosis who are not suitable candidates for surgery. The outcomes beyond 1 year in such patients are not known. METHODS We randomly assigned patients to transfemoral TAVR or to standard therapy (which often included balloon aortic valvuloplasty). Data on 2-year outcomes were analyzed. RESULTS A total of 358 patients underwent randomization at 21 centers. The rates of death at 2 years were 43.3% in the TAVR group and 68.0% in the standard-therapy group (P<0.001), and the corresponding rates of cardiac death were 31.0% and 62.4% (P<0.001). The survival advantage associated with TAVR that was seen at 1 year remained significant among patients who survived beyond the first year (hazard ratio, 0.58; 95% confidence interval [CI], 0.36 to 0.92; P=0.02 with the use of the log-rank test). The rate of stroke was higher after TAVR than with standard therapy (13.8% vs. 5.5%, P=0.01), owing, in the first 30 days, to the occurrence of more ischemic events in the TAVR group (6.7% vs. 1.7%, P=0.02) and, beyond 30 days, to the occurrence of more hemorrhagic strokes in the TAVR group (2.2% vs. 0.6%, P=0.16). At 2 years, the rate of rehospitalization was 35.0% in the TAVR group and 72.5% in the standard-therapy group (P<0.001). TAVR, as compared with standard therapy, was also associated with improved functional status (P<0.001). The data suggest that the mortality benefit after TAVR may be limited to patients who do not have extensive coexisting conditions. Echocardiographic analysis showed a sustained increase in aortic-valve area and a decrease in aortic-valve gradient, with no worsening of paravalvular aortic regurgitation. CONCLUSIONS Among appropriately selected patients with severe aortic stenosis who were not suitable candidates for surgery, TAVR reduced the rates of death and hospitalization, with a decrease in symptoms and an improvement in valve hemodynamics that were sustained at 2 years of follow-up. The presence of extensive coexisting conditions may attenuate the survival benefit of TAVR. (Funded by Edwards Lifesciences; ClinicalTrials.gov number, NCT00530894.).

Extent and Direction of Arterial Remodeling in Stable Versus Unstable Coronary Syndromes An Intravascular Ultrasound Study

BACKGROUND The morphological characteristics of coronary plaques in patients with stable versus unstable coronary syndromes have been described in vivo with intravascular ultrasound, but the relationship between arterial remodeling and clinical presentation is not well known. METHODS AND RESULTS We studied 85 patients with unstable and 46 patients with stable coronary syndromes using intravascular ultrasound before coronary intervention. The lesion site and a proximal reference site were analyzed. The remodeling ratio (RR) was defined as the ratio of the external elastic membrane (EEM) area at the lesion to that at the proximal reference site. Positive remodeling was defined as an RR >1.05 and negative remodeling as an RR <0.95. Plaque area (13.9+/-5.5 versus 11.1+/-4.8 mm(2); P=0.005), EEM area (16.1+/-6.2 versus 13.0+/-4.8 mm(2); P=0. 004), and the RR (1.06+/-0.2 versus 0.94+/-0.2; P=0.008) were significantly greater at target lesions in patients with unstable syndromes than in patients with stable syndromes. Positive remodeling was more frequent in unstable than in stable lesions (51. 8% versus 19.6%), whereas negative remodeling was more frequent in stable lesions (56.5% versus 31.8%) (P=0.001). CONCLUSIONS Positive remodeling and larger plaque areas were associated with unstable clinical presentation, whereas negative remodeling was more common in patients with stable clinical presentation. This association between the extent of remodeling and clinical presentation may reflect a greater tendency of plaques with positive remodeling to cause unstable coronary syndromes.

High Prevalence of Coronary Atherosclerosis in Asymptomatic Teenagers and Young Adults Evidence From Intravascular Ultrasound

Background—Most of our knowledge about atherosclerosis at young ages is derived from necropsy studies, which have inherent limitations. Detailed, in vivo data on atherosclerosis in young individuals are limited. Intravascular ultrasonography provides a unique opportunity for in vivo characterization of early atherosclerosis in a clinically relevant context. Methods and Results—Intravascular ultrasound was performed in 262 heart transplant recipients 30.9±13.2 days after transplantation to investigate coronary arteries in young asymptomatic subjects. The donor population consisted of 146 men and 116 women (mean age of 33.4±13.2 years). Extensive imaging of all possible (including distal) coronary segments was performed. Sites with the greatest and least intimal thickness in each CASS segment were measured in multiple coronary arteries. Sites with intimal thickness ≥0.5 mm were defined as atherosclerotic. A total of 2014 sites within 1477 segments in 574 coronary arteries (2.2 arteries per person) were analyzed. An atherosclerotic lesion was present in 136 patients, or 51.9%. The prevalence of atherosclerosis varied from 17% in individuals <20 years old to 85% in subjects ≥50 years old. In subjects with atherosclerosis, intimal thickness and area stenosis averaged 1.08±0.48 mm and 32.7±15.9%, respectively. For all age groups, the average intimal thickness was greater in men than women, although the prevalence of atherosclerosis was similar (52% in men and 51.7% in women). Conclusions—This study demonstrates that coronary atherosclerosis begins at a young age and that lesions are present in 1 of 6 teenagers. These findings suggest the need for intensive efforts at coronary disease prevention in young adults.

5-year outcomes of transcatheter aortic valve replacement or surgical aortic valve replacement for high surgical risk patients with aortic stenosis (PARTNER 1): a randomised controlled trial

BACKGROUND The Placement of Aortic Transcatheter Valves (PARTNER) trial showed that mortality at 1 year, 2 years, and 3 years is much the same with transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) for high-risk patients with aortic stenosis. We report here the 5-year outcomes. METHODS We did this randomised controlled trial at 25 hospitals, in Canada (two), Germany (one), and the USA (23). We used a computer-generated randomisation sequence to randomly assign high-risk patients with severe aortic stenosis to either SAVR or TAVR with a balloon-expandable bovine pericardial tissue valve by either a transfemoral or transapical approach. Patients and their treating physicians were not masked to treatment allocation. The primary outcome of the trial was all-cause mortality in the intention-to-treat population at 1 year, we present here predefined outcomes at 5 years. The study is registered with ClinicalTrials.gov, number NCT00530894. FINDINGS We screened 3105 patients, of whom 699 were enrolled (348 assigned to TAVR, 351 assigned to SAVR). Overall mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 11·7%. At 5 years, risk of death was 67·8% in the TAVR group compared with 62·4% in the SAVR group (hazard ratio 1·04, 95% CI 0·86-1·24; p=0·76). We recorded no structural valve deterioration requiring surgical valve replacement in either group. Moderate or severe aortic regurgitation occurred in 40 (14%) of 280 patients in the TAVR group and two (1%) of 228 in the SAVR group (p<0·0001), and was associated with increased 5-year risk of mortality in the TAVR group (72·4% for moderate or severe aortic regurgitation vs 56·6% for those with mild aortic regurgitation or less; p=0·003). INTERPRETATION Our findings show that TAVR as an alternative to surgery for patients with high surgical risk results in similar clinical outcomes. FUNDING Edwards Lifesciences.

Incidence, Predictors, and Outcomes of Aortic Regurgitation After Transcatheter Aortic Valve Replacement Meta-Analysis and Systematic Review of Literature

OBJECTIVES This study was designed to establish the incidence, impact, and predictors of post-transcatheter aortic valve replacement (TAVR) aortic regurgitation (AR). BACKGROUND AR is an important limitation of TAVR with ill-defined predictors and unclear long-term impact on outcomes. METHODS Studies published between 2002 and 2012 with regard to TAVR were identified using an electronic search and reviewed using the random-effects model of DerSimonian and Laird. From 3,871 initial citations, 45 studies reporting on 12,926 patients (CoreValve [Medtronic CV Luxembourg S.a.r.l., Tolochenaz, Switzerland] n = 5,261 and Edwards valve [Edwards Lifesciences, Santa Ana, California] n = 7,279) were included in the analysis of incidence and outcomes of post-TAVR AR. RESULTS The pooled estimate for moderate or severe AR post-TAVR was 11.7% (95% confidence interval [CI]: 9.6 to 14.1). Moderate or severe AR was more common with use of the CoreValve (16.0% vs. 9.1%, p = 0.005). The presence of moderate or severe AR post-TAVR increased mortality at 30 days (odds ratio: 2.95; 95% CI: 1.73 to 5.02) and 1 year (hazard ratio: 2.27; 95% CI: -1.84 to 2.81). Mild AR was also associated with an increased hazard ratio for mortality, 1.829 (95% CI: 1.005 to 3.329) that was overturned by sensitivity analysis. Twenty-five studies reported on predictors of post-TAVR AR. Implantation depth, valve undersizing, and Agatston calcium score (r = 0.47, p = 0.001) were identified as important predictors. CONCLUSIONS Moderate or severe aortic regurgitation is common after TAVR and an adverse prognostic indicator of short- and long-term survival. Incidence of moderate or severe AR is higher with use of the CoreValve. Mild AR may be associated with increased long-term mortality. Therefore, every effort should be made to minimize AR by a comprehensive pre-procedural planning and meticulous procedural execution.

Transcatheter Aortic Valve Implantation: Review of the Nature, Management, and Avoidance of Procedural Complications

Transcatheter aortic valve implantation (TAVI) is becoming a reality in the management of patients with severe aortic stenosis and high or prohibitive risk for standard surgical management. Current understanding of the potential adverse events associated with this procedure is limited. Risks associated with TAVI differ from those related to surgical valve replacement and include vascular injury; stroke; cardiac injury such as heart block, coronary obstruction, and cardiac perforation; paravalvular leak; and valve misplacement. The clinical experience of multiple centers experience with different valve implantation systems and techniques was reviewed. Awareness of how complications occur might help in their avoidance, recognition, and management. Ultimately, improved understanding of the potential complications associated with TAVI might help improve outcomes and allow wider application of this therapy.

Acute and 12-Month Results With Catheter-Based Mitral Valve Leaflet Repair : The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study

OBJECTIVES The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study (HRS) assessed the safety and effectiveness of the MitraClip device (Abbott Vascular, Santa Clara, California) in patients with significant mitral regurgitation (MR) at high risk of surgical mortality rate. BACKGROUND Patients with severe MR (3 to 4+) at high risk of surgery may benefit from percutaneous mitral leaflet repair, a potentially safer approach to reduce MR. METHODS Patients with severe symptomatic MR and an estimated surgical mortality rate of ≥12% were enrolled. A comparator group of patients screened concurrently but not enrolled were identified retrospectively and consented to compare survival in patients treated by standard care. RESULTS Seventy-eight patients underwent the MitraClip procedure. Their mean age was 77 years, >50% had previous cardiac surgery, and 46 had functional MR and 32 degenerative MR. MitraClip devices were successfully placed in 96% of patients. Protocol-predicted surgical mortality rate in the HRS and concurrent comparator group was 18.2% and 17.4%, respectively, and Society of Thoracic Surgeons calculator estimated mortality rate was 14.2% and 14.9%, respectively. The 30-day procedure-related mortality rate was 7.7% in the HRS and 8.3% in the comparator group (p = NS). The 12-month survival rate was 76% in the HRS and 55% in the concurrent comparator group (p = 0.047). In surviving patients with matched baseline and 12-month data, 78% had an MR grade of ≤2+. Left ventricular end-diastolic volume improved from 172 ml to 140 ml and end-systolic volume improved from 82 ml to 73 ml (both p = 0.001). New York Heart Association functional class improved from III/IV at baseline in 89% to class I/II in 74% (p < 0.0001). Quality of life was improved (Short Form-36 physical component score increased from 32.1 to 36.1 [p = 0.014] and the mental component score from 45.5 to 48.7 [p = 0.065]) at 12 months. The annual rate of hospitalization for congestive heart failure in surviving patients with matched data decreased from 0.59 to 0.32 (p = 0.034). CONCLUSIONS The MitraClip device reduced MR in a majority of patients deemed at high risk of surgery, resulting in improvement in clinical symptoms and significant left ventricular reverse remodeling over 12 months. (Pivotal Study of a Percutaneous Mitral Valve Repair System [EVEREST II]; NCT00209274).