Faculty Bibliography

OBJECTIVES/OBJECTIVE:This study sought to characterize the patients receiving post-implantation balloon dilation (PD) following transcatheter aortic valve replacement (TAVR) and evaluate procedural outcomes in the PARTNER (Placement of Aortic Transcatheter Valve) I trial. BACKGROUND:Following TAVR, PD has been used to treat paravalvular regurgitation. METHODS:The PARTNER I trial cohort A (n = 304) and cohort B (n = 194) patients randomized to TAVR and the nonrandomized continued access TAVR (n = 1,637) patients were included in the analysis. PD was performed at the discretion of the operator. Clinical events and echocardiographic variables were collected prospectively out to 1 year. RESULTS:The overall incidence of PD was 12.4%. PD patients had significantly less prosthesis-patient mismatch (p < 0.001) and larger effective orifice areas (p < 0.001) throughout the follow-up period. There were significantly more subacute strokes (occurring <7 days: 4.9% vs. 2.6%; p = 0.04) in PD patients but no difference in late stroke, either at 7 to 30 days (0.0% vs. 0.8%; p = 0.16) or >30 days (1.9 vs. 1.7%; p = 0.75). Although there was no significant increase in early mortality with PD, at 1 year, there was a trend for higher all-cause mortality (p = 0.054) and a significant difference in death or stroke (p = 0.04). When the subgroup of patients with none/trace paravalvular regurgitation were evaluated, there was no significant association of PD with mortality (p = 0.61) and death or stroke (p = 0.96). Multivariable analysis failed to show a relationship between PD and mortality. CONCLUSIONS:PD is associated with reduced rates of moderate or severe prosthesis-patient mismatch with no evidence for short-term structural deterioration of the balloon-expandable transcatheter valve. Although PD is associated with a greater incidence of early stroke, there is no significant association between PD and stroke beyond 7 days. Multivariable analysis shows no significant association between PD and mortality.

BACKGROUND:Patients with severe aortic stenosis (AS) who were deemed too high risk or inoperable for conventional aortic valve replacement (AVR) in the PARTNER (Placement of Aortic Transcatheter Valves) trial were randomized to transcatheter aortic valve replacement (TAVR) versus AVR (PARTNER-A arm) or standard therapy (PARTNER-B arm). OBJECTIVES/OBJECTIVE:This study compared when and how deaths occurred after TAVR versus surgical AVR or standard therapy. METHODS:The PARTNER-A arm included 244 transfemoral (TF) and 104 transapical (TA) TAVR patients, and 351 AVR patients; the PARTNER-B arm included 179 TF-TAVR patients and 179 standard therapy patients. Deaths were categorized as cardiovascular, noncardiovascular, or uncategorizable, and were characterized by multiphase hazard modelling. RESULTS:In the PARTNER-A arm, the risk of death peaked after randomization in the TA-TAVR and AVR groups, falling to low levels commensurate with the U.S. population within 3 months. Early risk was less in TF-TAVR patients, resulting in initial superior survival; between 12 and 18 months, risk increased, such that within 2 years, TF-TAVR and AVR patients had similar survival rates. Cardiovascular, noncardiovascular, and uncategorizable deaths for TF-TAVR were 37%, 43%, and 20%, respectively, versus 22%, 41%, and 37%, respectively, for TA-TAVR and 33%, 43%, and 24%, respectively, for AVR. In the PARTNER-B arm, risk with standard therapy was 60% per year; TF-TAVR reduced risk to 20% per year, resulting in 0.5 years of life added within 2.5 years. CONCLUSIONS:In inoperable AS patients, TAVR substantially reduced the risk of cardiovascular death. In high-risk patients, TA-TAVR and AVR were associated with elevated peri-procedural risk more than with TF-TAVR, although cardiovascular death was higher after TF-TAVR. Therefore, TF-TAVR should be considered the standard of care for severely symptomatic inoperable patients or those at high risk of noncardiovascular mortality after conventional surgery. (THE PARTNER TRIAL: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894).

BACKGROUND:The Placement of Aortic Transcatheter Valves (PARTNER) trial reported a reduced rate of mortality in patients with previous coronary bypass grafting (CABG) operation who received surgical aortic valve replacement (SAVR) in comparison with transcatheter aortic valve replacement (TAVR). We sought to further evaluate these groups. METHODS:We reviewed the database of the 699 patients enrolled in the PARTNER trial. The cohort for this study consisted of 288 patients (41.2%) who had a history of CABG operation before enrollment in the PARTNER trial. All patients were followed up for 2 years. RESULTS:The mean age was 81.5±6.6 years, and 231 patients (80.2%) were men. The preoperative characteristics were similar in 140 patients (48.6%) who received SAVR and 148 (51.4%) who received TAVR. There were no differences between the two groups with respect to the operative outcomes of death, stroke, and myocardial infarction, but the TAVR patients experienced more paravalvular regurgitation (p<0.0001). At 2 years, there was a trend toward greater all-cause mortality in the TAVR patients (hazard ratio [HR] 1.53; 95% confidence interval [CI]: 0.99, 2.35; p=0.052). Furthermore, the TAVR patients had more repeated hospitalization (HR 1.75; 95% CI: 0.99, 3.07; p=0.05), death of any cause or repeated hospitalization (HR 1.52; 95% CI: 1.06, 2.19; p=0.02), and death of any cause or stroke (HR 1.51; 95% CI: 1.00, 2.27; p=0.05). CONCLUSIONS:The 2-year follow-up of patients with a history of previous CABG operation in the PARTNER trial demonstrated improved outcomes with SAVR in comparison with TAVR. Further longitudinal assessment is necessary to corroborate these findings and to understand the possible causes.

AIMS/OBJECTIVE:This study aimed to evaluate incidence and correlates for low platelet count after transcatheter aortic valve replacement (TAVR) and to determine a possible association between acquired thrombocytopenia and clinical outcomes. METHODS AND RESULTS/RESULTS:Patients undergoing TAVR from two medical centres were included in the study. They were stratified according to nadir platelet count post procedure: no/mild thrombocytopenia, ≥100 × 10(9)/L; moderate, 50-99 × 10(9)/L; and severe, <50 × 10(9)/L. A total of 488 patients composed of the study population (age 84.7 ± 7.5 years). At a median time of 2 days after TAVR, 176 patients (36.1%) developed significant thrombocytopenia: 149 (30.5%) moderate; 27 patients (5.5%) severe. Upon discharge, the vast majority of patients (90.2%) had no/mild thrombocytopenia. Nadir platelet count <50 × 10(9)/L was highly specific (96.3%), and a count <150 × 10(9)/L highly sensitive (91.2%), for predicting 30-day death (C-statistic 0.76). Patients with severe acquired thrombocytopenia had a significantly higher mortality rate at 1 year (66.7% for severe vs. 16.0% for no/mild vs. 20.1% for moderate; P < 0.001). In multivariate logistic regression, severe thrombocytopenia was independently associated with 1-year mortality (hazard ratio 3.44, CI: 1.02-11.6; P = 0.046). CONCLUSIONS:Acquired thrombocytopenia was common after TAVR and was mostly resolved at patient discharge. The severity of thrombocytopenia after TAVR could be used as an excellent, easily obtainable, marker for worse short- and long-term outcomes after the procedure.

OBJECTIVES/OBJECTIVE:This study sought to examine sex-specific differences in outcomes after surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) in high-risk patients with severe aortic stenosis. BACKGROUND:The PARTNER (Placement of Aortic Transcatheter Valve) trial demonstrated similar 2-year survival with SAVR or TAVR for high-risk patients, but sex-specific outcomes are unknown. METHODS:In all, 699 patients (300 female) were randomly assigned 1:1 to either SAVR or TAVR with a balloon expandable pericardial tissue valve. Baseline characteristics and 2-year outcomes of TAVR versus SAVR were compared among males and females. RESULTS:Baseline characteristics differed between the sexes. Despite higher Society of Thoracic Surgeons mortality risk scores (11.9 vs. 11.6; p = 0.05), female patients had lower prevalence of coronary artery disease (64.4% vs. 83.7%), prior coronary artery bypass graft surgery (19.8% vs. 61.2%), peripheral vascular disease (36.4% vs. 46.9%), diabetes mellitus (35.6% vs. 45.6%), and elevated creatinine (11.7% vs. 23.9%). Among female patients, procedural mortality trended lower with TAVR versus SAVR (6.8% vs. 13.1%; p = 0.07) and was maintained throughout follow-up (hazard ratio [HR]: 0.67; 95% confidence interval [CI]: 0.44 to 1.00; p = 0.049), driven by the transfemoral arm (HR: 0.55; 95% CI: 0.32 to 0.93; p = 0.02). Among male patients, although procedural mortality was lower with TAVR (6% vs. 12.1%; p = 0.03), there was no overall survival benefit (HR: 1.15; 95% CI: 0.82 to 1.61; p = 0.42). CONCLUSIONS:In this retrospective subanalysis of high-risk, symptomatic aortic stenosis patients in the PARTNER trial, female subjects had lower late mortality with TAVR versus SAVR. This was especially true among patients suitable for transfemoral access and suggests that TAVR may be preferred over surgery for high-risk female patients. A randomized, controlled trial conducted specifically in female patients is necessary to properly study differences in mortality between treatment modalities. (THE PARTNER TRIAL: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894).

OBJECTIVE:Del Nido (DN) cardioplegia solution provides a depolarized hyperkalemic arrest lasting up to 60 minutes, and the addition of lidocaine may limit intracellular calcium influx. Single-dose DN cardioplegia solution may offer an alternative myocardial protection strategy to multi-dose cold whole blood (WB) cardioplegia following acute myocardial infarction (AMI). METHODS:We retrospectively reviewed 88 consecutive patients with AMI undergoing coronary artery bypass (CABG) surgery with cardioplegic arrest between June 2010 to June 2012. Patients exclusively received WB (n = 40, June 2010-July 2011) or DN (n = 48, August 2011-June 2012) cardioplegia. Preoperative and postoperative data were retrospectively reviewed and compared using propensity scoring. RESULTS:No significant difference in age, maximum preoperative serum troponin level, ejection fraction, and STS score was present between DN and WB. A single cardioplegia dose was given in 41 DN vs. 0 WB patients (p < 0.001), and retrograde cardioplegia was used 10 DN vs. 31 WB patients (p < 0.001). Mean cardiopulmonary bypass and cross clamp times were significantly shorter in the DN group versus WB group. Transfusion rate, length of stay, intra-aortic balloon pump requirement, post-operative inotropic support, and 30-day mortality was no different between groups. One patient in the WB group required a mechanical support due to profound cardiogenic shock. CONCLUSIONS:DN cardioplegia may provide equivalent myocardial protection to existing cardioplegia without negative inotropic effects in the setting of acute myocardial infarction.

OBJECTIVES: The goal of this study was to examine the impact of reasons for surgical inoperability on outcomes in patients undergoing transcatheter aortic valve replacement (TAVR). BACKGROUND: Patients with severe aortic stenosis may be deemed inoperable due to technical or clinical reasons. The relative impact of each designation on early and late outcomes after TAVR is unclear. METHODS: Patients were studied from the inoperable arm (cohort B) of the randomized PARTNER (Placement of Aortic Transcatheter Valve) trial and the nonrandomized continued access registry. Patients were classified according to whether they were classified as technically inoperable (TI) or clinically inoperable (CLI). Reasons for TI included porcelain aorta, previous mediastinal radiation, chest wall deformity, and potential for injury to previous bypass graft on sternal re-entry. Reasons for CLI were systemic factors that were deemed to make survival unlikely. RESULTS: Of the 369 patients, 23.0% were considered inoperable for technical reasons alone; the remaining were judged to be CLI. For TI, the most common cause was a porcelain aorta (42%); for CLI, it was multiple comorbidities (48%) and frailty (31%). Quality of life and 2-year mortality were significantly better among TI patients compared with CLI patients (mortality 23.3% vs. 43.8%; p < 0.001). Nonetheless, TAVR led to substantial survival benefits compared with standard therapy in both inoperable cohorts. CONCLUSIONS: Patients undergoing TAVR based solely on TI have better survival and quality of life improvements than those who are inoperable due to clinical comorbidities. Both TI and CLI TAVR have significant survival benefit in the context of standard therapy. (THE PARTNER TRIAL: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894).

We describe our experience using the Edwards Sapien transfemoral Retroflex 3 catheter delivery system for transcatheter aortic valve replacement through the transapical and transaortic approaches. Transthoracic transcatheter valve replacement by the transapical and transaortic approaches can be safely and effectively performed with the Retroflex 3 delivery catheter, which affords several advantages over other available delivery devices.