Faculty Bibliography

Objective: The longer dosing interval afforded by Del Nido cardioplegia (DNC) may simplify myocardial protection strategies. We analyzed the impact and safety of DNC in patients undergoing minimally invasive aortic valve replacement. Methods: Institutional use of DNC began in May 2013; we analyzed all isolated minimally invasive aortic valve replacements during this transition (May 2013-June 2015), excluding reoperative sternotomy patients. The approach was hemi-median sternotomy in all patients. Prospectively collected local and Society of Thoracic Surgeons database data were used. Patients were divided into 2 cohorts: those who received 4:1 crystalloid:blood DNC solution and those in whom standard 1:4 Buckberg-based cardioplegia (BC) was used. One-to-one propensity case matching of DNC to Buckberg-based cardioplegia was performed based on standard risk factors, and differences between groups were analyzed using X² and nonparametric methods. Results: Minimally invasive aortic valve replacement was performed in 181 patients; DNC was usedin 59 and Buckberg-based cardioplegia in 122. Case matching resulted in 59 patients per cohort. DNC was associated with reduced re-dosing [5/59 (8.5%) vs. 39/59 (61.0%), P<0.001] and less total cardioplegia volume (1290 ml+/-347 ml vs. 2284 ml+/-828 ml, P<0.001). Antegrade cardioplegia alone was used in 89.8% (53/59) of DNC patients versus 33.9% (20/59) of patients receiving Buckberg-based cardioplegia (P<0.001). Median bypass and aortic cross-clamp times were similar. Clinical outcomes were similar with respect to postoperative hematocrit, transfusion requirements, need for inotropic/pressor support, duration of stay in the intensive care unit, re-intubation, length of hospital stay, new onset atrial fibrillation, and mortality rate. Table SA15-1 contains demographics, cardioplegia delivery methods, and results. Conclusions: DNC usage markedly simplifies cardioplegia strategy for minimally invasive aortic valve replacement. Patient safety was not compromised with this technique. (Table pasented)

BACKGROUND: Nearly 17% of patients are readmitted within 30 days of discharge after transcatheter aortic valve replacement. Selected patients are discharged to skilled nursing facilities, yet the association between a hospital's practice to discharge home versus to skilled nursing facilities, and readmission remains unclear. METHODS AND RESULTS: The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy (STS/ACC TVT) Registry was used to evaluate readmissions among patients undergoing transcatheter aortic valve replacement (2011-2015). Hospitals were divided into quartiles (Q1-Q4) based on the percentage of patients discharged directly home. We assessed patient and hospital level characteristics and used hierarchical logistic regression to analyze the association of discharge disposition with 30-day readmission. Our cohort included 18 568 transcatheter aortic valve replacement patients at 329 US hospitals, of whom 69% were discharged directly home. Hospitals in the highest quartile of direct home discharge (Q4) compared with hospitals in the lowest (Q1) were more likely to use femoral access (75.2% versus 60.1%, P<0.001), had fewer patients receiving transfusion (26.4% versus 40.9%, P<0.001), and were more likely to be located in the Southern United States (48.8% versus 18.3%, P<0.001). Median 30-day readmission rate was 17.9%. There was no significant difference in 30-day readmissions among quartiles (P=0.14), even after multivariable adjustment (odds ratio Q4 versus Q1=0.89, 95%CI 0.76-1.04; P=0.15). Factors most strongly associated with 30-day readmission were glomerular filtration rate, in-hospital stroke or transient ischemic attack, and nonfemoral access. CONCLUSIONS: There was no statistically significant association between hospital practice of direct home discharge post-transcatheter aortic valve replacement and 30-day readmission. Further research is needed to understand regional variations and optimum strategies for postdischarge care.

BACKGROUND: Bundled Payments for Care Improvement (BPCI) initiatives were developed by Medicare in an effort to reduce expenditures while preserving quality of care. Payment model 2 reimburses based on a target price for 90-day episode of care postprocedure. The challenge for valve patients is the historically high (>35%) 90-day readmission rate. We analyzed our institutional cardiac surgical service line adaptation to this initiative. METHODS: On May 1, 2015, we instituted a readmission reduction initiative (RRI) that included presurgical risk stratification, comprehensive predischarge planning, and standardized postdischarge management led by cardiac nurse practitioners (CNPs) who attempt to guide any postdischarge encounters (PDEs). A prospective database also was developed, accruing data on all cardiac surgery patients discharged after RRI initiation. We analyzed detailed PDEs for all valve patients with complete 30-day follow-up through November 2015. RESULTS: Patients included 219 surgical patients and 126 transcatheter patients. Sixty-four patients had 79 PDEs. Of these 79 PDEs, 46 (58.2%) were guided by CNPs. PDEs were due to fluid overload/effusion (21, 27%), arrhythmia (17, 22%), bleeding/thromboembolic events (13, 16%), and falls/somatic complaints (12, 15%). Thirty-day readmission rate was 10.1% (35/345). Patients with transcatheter aortic valve replacement had a higher rate of readmission than surgical patients (15.0% vs 6.9%), but were older with more comorbidities. The median readmission length of stay was 2.0 days (interquartile range 1.0-5.0 days). Compared with 2014, the 30-day readmission rate for BPCI decreased from 18% (44/248) to 11% (20/175), P = .05. CONCLUSIONS: Our reengineering of pre/postdischarge management of BPCI valve patients under tight CNP control has significantly reduced costly 30-day readmissions in this high-risk population.

Atrial fibrillation (AF) is associated with worse outcomes in many cardiovascular diseases. There are few data examining pacemaker implantation rates and indications in patients with AF who undergo transcatheter aortic valve replacement (TAVR). To examine the impact of AF on the incidence of and indications for pacemakers in patients undergoing TAVR, we evaluated data of 1723 patients without pre-existing pacemakers who underwent TAVR in the Placement of AoRTic TraNscathetER Valve (PARTNER) trial. Permanent pacemaker implantation rates and indications were compared in groups based on baseline and discharge heart rhythm: sinus rhythm (SR) vs. AF. 1211 patients manifested SR at baseline/SR at discharge (SR/SR), 105 SR baseline/AF discharge (SR/AF), and 407 AF baseline/AF discharge (AF/AF). Patients who developed and were discharged with AF (SR/AF) had the highest rates of pacemaker implantation at 30 days (13.7% SR/AF vs. 5.4% SR/SR, p=0.0008 and 5.9% AF/AF, p=0.008) and 1 year (17.7% SR/AF vs. 7.1% SR/SR, p=0.0002 and 8.1% AF/AF, p=0.0034). Conversion from SR to AF by discharge was an independent predictor of increased pacemaker implantation at 30 days (HR 2.19 vs. SR/SR, 95% CI 1.23-3.93, p=0.008) and 1 year (HR 1.91 vs. SR/SR, 95% CI 1.33-3.80). Pacemaker indications differed between groups, with relatively more implanted in the AF groups for sick sinus syndrome (SSS) versus AV block. In conclusion, conversion to AF is an independent predictor of permanent pacemaker implantation in TAVR patients. Indications differ depending on heart rhythm, with patients in AF manifesting clinically significant tachy-brady syndrome versus AV block.

BACKGROUND: Appropriate valve sizing is critical in aortic valve replacement. We hypothesized that direct intraoperative valve sizing results in smaller aortic annular diameters compared with sizing based on systolic-phase multidetector computerized tomographic (MDCT) imaging. METHODS AND RESULTS: We retrospectively analyzed 78 patients undergoing surgical aortic valve replacement for severe aortic stenosis between 2012 and 2014 at our institution. Preoperative MDCT measurements of the aortic annulus served as basis for assignment to a theoretical surgical valve size, which was then (1) compared to the implanted valve size and (2) to a theoretical transcatheter aortic valve replacement valve size. To quantify the resulting differences, geometric orifice areas (GOA) were calculated. MDCT-based sizing produced the same valve size for n=34 patients (group CT-same), a larger valve with a 25% increased GOA in n=32 patients (group CT-Lg) and a smaller GOA by 22% in n=12 patients (group CT-Sm). On the basis of MDCT measurements, 41% of valves implanted were undersized. The comparison of intraoperative implanted to a theoretical transcatheter aortic valve replacement valve size resulted in GOAs 25% larger for patients in group CT-same, 40.6% larger in group CT-Lg and 14.6% larger in group CT-Sm. CONCLUSIONS: Preoperative MDCT measurements differ substantially from direct intraoperative assessment of the aortic annulus. Implanted surgical aortic valve replacement valves were smaller relative to MDCT-based sizing in 41% of patients, and the potential GOA was between 25% and 40.6% larger if patients had undergone transcatheter aortic valve replacement.

Background: Patients with severe aortic stenosis in the setting of low gradient and preserved left ventricular ejection fraction (LVEF) remain an area of clinical uncertainty. Methods: Retrospective chart review identified 209 patients who underwent transcatheter aortic valve replacement (TAVR) between September 2014 and September 2015. Of these patients, 3 (1.4%) were excluded due to procedural indication other than severe aortic stenosis and 41 (20%) were excluded due to reduced LVEF (<50%). Of the remaining 165 patients with aortic valve area <1 cm2, 77 (47%) had either a peak velocity <4.0 m2 or mean gradient <40 mmHg (LG group) and 88 (53%) had both peak velocity >4.0 m2 and mean gradient >40 mmHg (HG group) across the AV. Outcomes were defined by the valve academic research consortium 2 criteria when applicable and compared between the LG and HG groups via Fisher's exact test. Median follow-up was 367 days. Continuous data are shown as median [interquartile range] and categorical data are shown as proportions. Results: The 30-day mortality risk as assessed by Society of Thoracic Surgery score was not significantly different between the LG and HG groups (5.9% [3.5-8.1] vs 6.2% [4.4-7.6], p=0.45). There were no significant differences in outcomes (Table). Conclusion: In a high-volume center, patients undergoing TAVR for severe AS with LG preserved LVEF have no significant difference in adverse outcomes, both in-hospital and on 1-year follow-up, when compared to patients with HG preserved LVEF. (Figure Presented)

Background Although transcatheter aortic-valve replacement (TAVR) is an accepted alternative to surgery in patients with severe aortic stenosis who are at high surgical risk, less is known about comparative outcomes among patients with aortic stenosis who are at intermediate surgical risk. Methods We evaluated the clinical outcomes in intermediate-risk patients with severe, symptomatic aortic stenosis in a randomized trial comparing TAVR (performed with the use of a self-expanding prosthesis) with surgical aortic-valve replacement. The primary end point was a composite of death from any cause or disabling stroke at 24 months in patients undergoing attempted aortic-valve replacement. We used Bayesian analytical methods (with a margin of 0.07) to evaluate the noninferiority of TAVR as compared with surgical valve replacement. Results A total of 1746 patients underwent randomization at 87 centers. Of these patients, 1660 underwent an attempted TAVR or surgical procedure. The mean (+/-SD) age of the patients was 79.8+/-6.2 years, and all were at intermediate risk for surgery (Society of Thoracic Surgeons Predicted Risk of Mortality, 4.5+/-1.6%). At 24 months, the estimated incidence of the primary end point was 12.6% in the TAVR group and 14.0% in the surgery group (95% credible interval [Bayesian analysis] for difference, -5.2 to 2.3%; posterior probability of noninferiority, >0.999). Surgery was associated with higher rates of acute kidney injury, atrial fibrillation, and transfusion requirements, whereas TAVR had higher rates of residual aortic regurgitation and need for pacemaker implantation. TAVR resulted in lower mean gradients and larger aortic-valve areas than surgery. Structural valve deterioration at 24 months did not occur in either group. Conclusions TAVR was a noninferior alternative to surgery in patients with severe aortic stenosis at intermediate surgical risk, with a different pattern of adverse events associated with each procedure. (Funded by Medtronic; SURTAVI ClinicalTrials.gov number, NCT01586910 .).