Faculty Bibliography

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).

OBJECTIVES: Advanced age plays a major role in surgical risk algorithms; however, the outcomes data for the very elderly are lacking. We, therefore, evaluated the outcomes after surgical aortic valve replacement (SAVR) in nonagenarians (age, >90 years) at our institution during an 11-year period. METHODS: The demographics, procedural details, and in-hospital outcomes were retrospectively analyzed for 119 nonagenarians with symptomatic, severe aortic stenosis who had undergone SAVR or SAVR plus concomitant surgery from 2001 to 2012. The mean follow-up period was 915 +/- 832 days. RESULTS: The average age was 91.7 +/- 1.9 years (range, 90-98), and the mean Society of Thoracic Surgeons score was 8.9 +/- 5.7. The mean aortic valve gradient was 45 +/- 16 mm Hg, mean aortic valve area was 0.66 +/- 0.2 cm2, and mean ejection fraction was 49.8% +/- 11.8%; 47% underwent isolated SAVR. The average length of stay was longer than expected; however, the rates of prolonged ventilation (16.8%), new atrial fibrillation (43.7%), stroke (0.8%), and renal failure (5.9%) were acceptable. Three patients (2.5%) required reoperation for bleeding. Overall, the 30-day and 1-year mortality was 7.6% and 21.0%, respectively. The multivariate predictors of mortality at 1 year included previous myocardial infarction (hazard ratio, 2.79; 95% confidence interval, 1.21-6.45; P = .016), obstructive lung disease (hazard ratio, 3.90; 95% confidence interval, 1.66-9.15; P = .025), and diabetes (hazard ratio, 2.77; 95% confidence interval, 1.08-7.07; P = .033). The observed in-hospital mortality was lower than expected (observed/expected, 0.85). CONCLUSIONS: Excellent procedural and long-term outcomes can be achieved in nonagenarians, and age alone should not be a contraindication to SAVR in selected populations. Our sample cohort has validated the feasibility of a primary operative strategy in elderly patients with aortic stenosis and acceptable risk profiles.

BACKGROUND: Previous studies have shown cross-sectional 3-dimensional (3D) transesophageal echocardiographic (TEE) measurements to severely underestimate multidetector row computed tomographic (MDCT) measurements for the assessment of aortic annulus before transcatheter aortic valve replacement. This study compares annulus measurements from 3D-TEE using off-label use of commercially available software with MDCT measurements and assesses their ability to predict paravalvular regurgitation. METHODS AND RESULTS: One hundred patients with severe, symptomatic aortic stenosis who had both contrast MDCT and 3D-TEE for annulus assessment before balloon-expandable transcatheter aortic valve replacement were analyzed. Annulus area, perimeter, and orthogonal maximum and minimum diameters were measured. Receiver operating characteristic analysis was performed with mild or greater paravalvular regurgitation as the classification variable. Three-dimensional TEE and MDCT cross-sectional perimeter and area measurements were strongly correlated (r=0.93-0.94; P<0.0001); however, the small differences (/= mild paravalvular regurgitation was good for both MDCT (area under the curve for perimeter and area cover index=0.715 and 0.709, respectively) and 3D-TEE (area under the curve for perimeter and area cover index=0.709 and 0.694, respectively). Differences in receiver operating characteristic analysis between MDCT and 3D-TEE perimeter and area cover indexes were not statistically significant (P=0.15 and 0.35, respectively). CONCLUSIONS: Annulus measurements using a new method for analyzing 3D-TEE images closely approximate those of MDCT. Annulus measurements from both modalities predict mild or greater paravalvular regurgitation with equivalent accuracy.

Patients with severe aortic stenosis are commonly elderly and with significant comorbidity. Surgical intervention can improve symptoms and survival in severe aortic stenosis. However, a large proportion of patients do not undergo surgical intervention because they are deemed to be inoperable or too high risk. Over the last decade, transcatheter aortic valve replacement (TAVR) has been developed, providing an effective, less-invasive alternative to open cardiac surgery for inoperable or high-risk patients. The purpose of this review is to provide an overview of risk assessment in TAVR. Specifically, this article reviews the epidemiology of aortic stenosis, describes the risks and benefits of TAVR across multiple outcome measures, explores frailty and other elderly risk factors as metrics for improved risk assessment and discusses the application of improved risk assessment in TAVR decisions.