Faculty Bibliography

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.

Recently, transcatheter valve-in-valve implantation has emerged as a new alternative to surgical reoperation for degenerated bioprosthetic valves, either in the aortic or mitral position. The early experience and outcome of this strategy appears promising in highly selected patient groups. Here we report a case of early structural valve degeneration in the aortic and mitral position in a patient with chronic hemodialysis successfully treated with transthoracic transcatheter valve-in-valve implantation.

BACKGROUND AND AIMS: The immediate postischemic period is marked by elevated intracellular calcium levels, which can lead to irreversible myocyte injury. Del Nido cardioplegia was developed for use in the pediatric population to address the inability of immature myocardium to tolerate high levels of intracellular calcium following cardiac surgery. Our aim in this study is to determine if this solution can be used safely and effectively in an adult, reoperative population. METHODS: All patients undergoing isolated reoperative aortic valve replacement at our institution from 2010 to 2012 were retrospectively reviewed. Demographics, comorbidities, operative variables, postoperative complications, and patient outcomes were collected. Patients were divided into two groups based on cardioplegia strategy used: whole blood cardioplegia (WB, n = 61) and del Nido cardioplegia (DN, n = 52). RESULTS: Mean age in the study was 73.4 +/- 14.3 years and 86 patients were male (76.1%). Eighty-four patients had undergone prior coronary artery bypass graft (CABG) (74.3%). Patients in the DN group required significantly lower total volume of cardioplegia (1147.6 +/- 447.2 mL DN vs. 1985.4 +/- 691.1 mL WB, p < 0.001) and retrograde cardioplegia dose (279.3 +/- 445.1 mL DN vs. 1341.2 +/- 690.8 mL WB, p < 0.001). There were no differences in cross-clamp time, bypass time, postoperative complication rate, or patient outcomes between groups. CONCLUSIONS: Del Nido cardioplegia use in an adult, reoperative aortic valve population offers equivalent postoperative outcomes when compared with whole blood cardioplegia. In addition, use of del Nido solution requires lower total and retrograde cardioplegia volumes in order to achieve adequate myocardial protection. doi: 10.1111/jocs.12360 (J Card Surg 2014;29:445-449).

AIMS: Cardiac conduction disturbances, including a left bundle branch block (LBBB), occur frequently following transcatheter aortic valve replacement (TAVR) and may be associated with adverse clinical events. This analysis examines the incidence and implications of new onset, persistent LBBB in patients undergoing TAVR with a balloon-expandable valve. METHODS AND RESULTS: Patients undergoing TAVR in the Placement of Aortic Transcatheter Valves (PARTNER) trial and continued access registries with baseline and discharge/7-day electrocardiograms were included. Prior permanent pacemaker implantation (PPI) and baseline intraventricular conduction abnormalities were exclusion criteria. Predictors of new LBBB were identified and outcomes compared between patients with and without new LBBB. New LBBB occurred in 121 of 1151 (10.5%) patients and persisted in more than half at 6 months to 1 year. The only predictor of new LBBB was prior coronary artery bypass grafting. New LBBB was not associated with significant differences in 1-year mortality, cardiovascular mortality, repeat hospitalization, stroke, or myocardial infarction. However, it was associated with increased PPI during hospitalization (8.3 vs 2.8%, P = 0.005) and from discharge to 1 year (4.7 vs. 1.5%, P = 0.01). The ejection fraction failed to improve after TAVR in patients with new LBBB and remained lower at 6 months to 1 year (52.8 vs. 58.1%, P < 0.001). CONCLUSION: Persistent, new-onset LBBB occurred in 10.5% of patients without intraventricular baseline conduction who underwent TAVR in the PARTNER experience. New LBBB was not associated with death, repeat hospitalization, stroke, or myocardial infarction at 1 year, but was associated with a higher rate of PPI and failure of left ventricular ejection fraction to improve.

OBJECTIVES: This study sought to identify the incidence, predictors, and prognostic impact of bleeding complications (BC) after surgical aortic valve replacement (SAVR) compared with transcatheter aortic valve replacement (TAVR). BACKGROUND: Bleeding complications after SAVR and TAVR are frequent and may be associated with an unfavorable prognosis. METHODS: In the randomized controlled PARTNER (Placement of Aortic Transcatheter Valve) I trial, 657 patients from cohort A (operable high risk) were randomly assigned to SAVR or TAVR (transfemoral [TF] if iliofemoral access was suitable or transapical [TA] if not) and received the designated treatment. First-generation Edwards SAPIEN valves and delivery systems (Edwards Lifesciences, Irvine, California) were used for TAVR, through a 22- or 24-F sheath. The 30-day rates of major BC (modified Valve Academic Research Consortium definitions), predictors of BC, and their association with 1-year mortality were assessed. RESULTS: A total of 71 (22.7%), 27 (11.3%), and 9 (8.8%) patients had major BC within 30 days of the procedure after SAVR, TF-TAVR, and TA-TAVR, respectively (p < 0.0001). SAVR was associated with a significantly higher 30-day rate of transfusion (17.9%) than either TF-TAVR (7.1%) or TA-TAVR (4.8%; p < 0.0001). Independent predictors of major BC were the occurrence of major vascular complications and use of intraprocedural hemodynamic support among TF-TAVR patients, severe procedural complications requiring conversion to open surgery among TA-TAVR patients, and the presence of low hemoglobin at baseline among SAVR patients. Major BC was identified as the strongest independent predictor of 1-year mortality among the full cohort. However, risk-adjusted analyses demonstrated a significant interaction between BC and treatment strategy with respect to mortality, suggesting that BC after SAVR have a greater impact on prognosis than after TAVR. CONCLUSIONS: Among high-risk aortic stenosis patients enrolled in the PARTNER I randomized trial, BC were more common after SAVR than after TAVR and were also associated with a worse long-term prognosis. (THE PARTNER TRIAL: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894).