Increasing Adoption of Left Atrial Appendage Occlusion in Isolated Coronary Artery Bypass Grafting.

BACKGROUND: Recent randomized trial data showed fewer strokes with left atrial appendage occlusion (LAAO) following cardiac surgery in patients with atrial fibrillation. We developed a quality initiative to increase LAAO adoption. METHODS: Among 11,099 patients undergoing isolated CABG between January 2019-March 2021 at 33 hospitals in Michigan, those with atrial fibrillation undergoing first-time, on-pump CABG were eligible (n=1,241). A goal LAAO rate of 75% was selected as a quality improvement target through a statewide collaborative. An interrupted time series analysis evaluated the change in LAAO rate before (January-December 2019) versus after (January 2020-March 2021) implementation. RESULTS: Implementation of the quality metric improved LAAO rate from 61% (357/581) before to 79% (520/660) after implementation (p<0.001). Compared to patients not undergoing concomitant LAAO, LAAO patients (71%, 877/1,241) were older, more frequently male, and had a lower STS-PROM (2.9±3.5% vs. 3.7±5.7%, p=0.003), while other baseline characteristics including CHA2DS2-VASc scores were similar. Mean bypass and cross-clamp times were 7 and 6 minutes longer, respectively, in the LAAO group among those who did not undergo concomitant ablation. Operative mortality, major morbidity, blood product administration, and thromboembolic events were similar between groups. Interrupted time series analysis showed a significant increase in LAAO rate after implementation (p=0.009). CONCLUSIONS: LAAO in patients with atrial fibrillation undergoing isolated CABG did not add operative risk versus isolated CABG without LAAO. A statewide quality improvement initiative was successful in increasing the rate of concomitant LAAO and could be further evaluated as a potential quality metric in cardiac surgery.

Determinants and Outcomes Associated With Skilled Nursing Facility Use After Coronary Artery Bypass Grafting: A Statewide Experience.

BACKGROUND: Skilled nursing facility (SNF) care is frequently used after cardiac surgery, but the patterns and determinants of use have not been well understood. The objective of this study was to evaluate determinants and outcomes associated with SNF use after isolated coronary artery bypass grafting. METHODS: A retrospective analysis of Medicare Fee-For-Service claims linked to the Society of Thoracic Surgeons clinical data was conducted on isolated coronary artery bypass grafting patients without prior SNF use in Michigan between 2011 and 2019. Descriptive analysis evaluated the frequency, trends, and variation in SNF use across 33 Michigan hospitals. Multivariable mixed-effects regression was used to evaluate patient-level demographic and clinical determinants of SNF use and its effect on short- and long-term outcomes. RESULTS: In our sample of 8614 patients, the average age was 73.3 years, 70.5% were male, and 7.7% were listed as non-White race. An SNF was utilized by 1920 (22.3%) patients within 90 days of discharge and varied from 3.2% to 58.3% across the 33 hospitals. Patients using SNFs were more likely to be female, older, non-White, with more comorbidities, worse cardiovascular function, a perioperative morbidity, and longer hospital lengths of stay. Outcomes were significantly worse for SNF users, including more frequent 90-day readmissions and emergency department visits and less use of home health and rehabilitation services. SNF users had higher risk-adjusted hazard of mortality (hazard ratio, 1.41 [95% CI, 1.26-1.57]; P<0.001) compared with non-SNF users and had 2.7-percentage point higher 5-year mortality rate in a propensity-matched cohort of patients (18.1% versus 15.4%; P<0.001). CONCLUSIONS: The use of SNF care after isolated coronary artery bypass grafting was frequent and variable across Michigan hospitals and associated with worse risk-adjusted outcomes. Standardization of criteria for SNF use may reduce variability among hospitals and ensure appropriateness of use.

Lessons learned from the EACTS-MSTCVS quality fellowship: a call to action for continuous improvement of cardiothoracic surgery outcomes in Europe.

The Michigan Society of Thoracic and Cardiovascular Surgeons (MSTCVS), a pioneer in initiating and nurturing quality improvement strategies in statewide cardiothoracic surgery, has been running the Quality Collaborative (MSTCVS-QC) program since 2001. This initiative has significantly grown over the years, facilitating at least 4 in-person meetings annually. It actively engages cardiac and general thoracic surgeons, data managers and researchers from all 32 non-federally funded cardiothoracic surgery sites across Michigan. Broadening its influence on joint learning and clinical outcomes, the MSTCVS-QC formed a strategic partnership with Blue Cross Blue Shield of Michigan, the state's largest private insurer, to further promote its initiatives. The MSTCVS-QC, operating from a dedicated QC centre employs an STS-associated database with additional aspects for data collection and analysis. The QC centre also organizes audits, facilitates collaborative meetings, disseminates surgical outcomes and champions the development and implementation of quality improvement initiatives related to cardiothoracic surgery in Michigan. Recognizing the MSTCVS-QC's successful efforts in advancing quality improvement, the European Association for Cardiothoracic Surgery (EACTS) introduced a fellowship program in 2018, facilitated through the EACTS Francis Fontan Fund (FFF). This program allows early-career academic physicians to spend 4-6 months with the MSTCVS-QC team in Ann Arbor. This article chronicles the evolution and functionality of the MSTCVS-QC, enriched by the experiences of the inaugural 4 EACTS/FFF fellows. Our objective is to emphasize the critical importance of fostering a culture of quality improvement and patient safety in the field of cardiothoracic surgery with open discussion of audited, high-quality data points. This principle, while implemented locally, has implications and value extending far beyond Europe, resonating globally.

Barriers to atrial fibrillation ablation during mitral valve surgery.

BACKGROUND: Nearly 40% of patients with atrial fibrillation (AF) undergoing mitral valve surgery do not receive concomitant ablation despite societal guidelines. We assessed barriers to implementation of this evidence-based practice through a survey of cardiac surgeons in 2 statewide quality collaboratives. METHODS: Adult cardiac surgeons across 2 statewide collaboratives were surveyed on their knowledge and practice regarding AF ablation. Questions concerning experience, clinical practice, case scenarios, and barriers to implementation were included. RESULTS: Among 66 respondents (66 of 135; 48.9%), the majority reported "very comfortable/frequently use" cryoablation (53 of 66; 80.3%) and radiofrequency (55 of 66; 83.3%). Only 12.1% (8/66) were not aware of the recommendations. Approximately one-half of the respondents reported learning AF ablation in fellowship (50.0%; 33 of 66) or attending courses (47.0%; 31 of 66). Responses to clinical scenarios demonstrated wide variability in practice patterns. One-half of the respondents reported no barriers; others cited increased cross-clamp time, excessive patient risk, and arrhythmia incidence as obstacles. Desired interventions included cardiology/electrophysiology support, protocols, pacemaker rate information, and education in the form of site visits, videos and proctors. CONCLUSIONS: Knowledge of evidence-based recommendations and practice patterns vary widely. These data identify several barriers to implementation of concomitant AF ablation and suggest specific interventions (mentorship/support, protocols, research, and education) to overcome these barriers.

Racial disparities in mitral valve surgery: A statewide analysis.

OBJECTIVE: Racial disparities in health care have come to the forefront. We hypothesized that Black race was associated with worse preoperative risk, lower repair rates, and worse outcomes among patients who underwent mitral valve surgery. METHODS: All patients who underwent mitral valve repair or replacement with or without coronary artery bypass grafting from 2011 to 2020 in a statewide collaborative database were stratified into 3 racial groups, White, Black, and other. Preoperative characteristics, procedure type, and outcomes were evaluated. RESULTS: A total of 9074 mitral valve operations were performed at 33 centers (Black 1009 [11.1%], White 7862 [86.6%]). Preoperative combined Society of Thoracic Surgeons morbidity and mortality was higher for Black patients (Black 32%, White 22%, other 23%, [P < .001]) because of a greater proportion of diabetes, hypertension, and chronic lung disease. White patients were more likely to undergo mitral repair (White 66%, Black 53.3%, other 57%; P < .001). Operative mortality was similar across racial groups (White 3.7%, Black 4.6%, other 4.5%; P = .36). After adjusting for preoperative factors, mitral etiology, and hospitals, race was not associated with mitral valve repair, complications, or mortality, but Black patients had higher odds of extended care facility utilization and readmission. CONCLUSIONS: Contrary to our hypothesis, there was no difference in the odds of repair or operative mortality across races after accounting for risk and etiology. However, Black patients were more likely to be readmitted after discharge. These findings support a greater focus on reducing disparities in mitral valve surgery.

Pixel-based approach to delay multiply and sum beamforming in combination with Wiener filter for improving ultrasound image quality.

Unified pixel-based (PB) beamforming has been implemented for ultrasound imaging, offering significant enhancements in lateral resolution compared to the conventional dynamic focusing. However, it still suffers from clutter and off-axis artifacts, limiting the contrast resolution. This paper proposes an efficient method to improve image quality by integrating filtered delay multiply and sum (F-DMAS) into the framework. This hybrid strategy incorporates the spatial coherence of the received data into the beamforming process to improve contrast resolution and clutter rejection in the generated image. We also integrate a Wiener filter to suppress the spatiotemporal spreading using signals echoed from a single scatterer at the transmit focus as a kernel for the deconvolution. The Wiener filter is applied to the received waveforms before performing the hybrid strategy. The Wiener filter is shown to reduce interference due to the interaction between the excitation pulse and the transfer functions of the transducer elements, thus benefiting the axial resolution of the generated images. We validate the proposed method and compare it with other beamforming strategies through a series of experiments, including simulation, phantom, and in vivo studies. The results show that our approach can substantially improve both spatial resolution and contrast over the unified PB algorithm, while still maintaining the good features of this beamformer. The simplicity and good performance of our method show its potential for use in clinical applications.

Contemporary Management of Ischemic Mitral Regurgitation at Coronary Artery Bypass Grafting.

BACKGROUND: Recent guidelines for the treatment of moderate or severe ischemic mitral regurgitation (IMR) in patients undergoing coronary artery bypass grafting (CABG) have changed. This study assessed the real-world impact of changing guidelines on the management of IMR during CABG over time. We hypothesized that the utilization of mitral valve repair for IMR would decrease over time, whereas mitral valve replacement for severe IMR would increase. METHODS: Patients undergoing CABG in a statewide collaborative database (2011-2020) were stratified by severity of IMR. Trends in mitral valve repair or replacement were evaluated. To account for differences of the patients, propensity score-matched analyses were used to compare patients with and without mitral intervention. RESULTS: A total of 11,676 patients met inclusion criteria, including 1355 (11.6%) with moderate IMR and 390 (3.3%) with severe IMR. The proportion of patients undergoing mitral intervention for moderate IMR decreased over time (2011, 17.7%; 2020, 7.5%; Ptrend = .001), whereas mitral replacement for severe IMR remained stable (2011, 11.1%; 2020, 13.3%; Ptrend = .14). Major morbidity was higher for patients with moderate IMR who underwent mitral intervention (29.1% vs 19.9%; P = .005). In a propensity analysis of 249 well-matched pairs, there was no difference in major morbidity (29.3% with mitral intervention vs 23.7% without; P = .16) or operative mortality (1.2% vs 2.4%; P = .5). CONCLUSIONS: Consistent with recent guideline updates, patients with moderate IMR were less likely to undergo mitral repair. However, the rate of replacement for severe IMR did not change. Mitral intervention during CABG did not increase operative mortality or morbidity.

Area Deprivation and Medicare Spending for Coronary Artery Bypass Grafting: Insights From Michigan.

BACKGROUND: Prior work has established that high socioeconomic deprivation is associated with worse short- and long-term outcomes for patients undergoing coronary artery bypass grafting (CABG). The relationship between socioeconomic status and 90-day episode spending is poorly understood. In this observational cohort analysis, we evaluated whether socioeconomically disadvantaged patients were associated with higher expenditures during 90-day episodes of care after isolated CABG. METHODS: We linked clinical registry data from 8728 isolated CABG procedures from January 1, 2012, to December 31, 2018, to Medicare fee-for-service claims data. Our primary exposure variable was patients in the top decile of the Area Deprivation Index. Linear regression was used to compare risk-adjusted, price-standardized 90-day episode spending for deprived against nondeprived patients as well as component spending categories: index hospitalization, professional services, post acute care, and readmissions. RESULTS: A total of 872 patients were categorized as being in the top decile. Mean 90-day episode spending for the 8728 patients in the sample was $55 258 (SD, $26 252). Socioeconomically deprived patients had higher overall 90-day spending compared with nondeprived patients ($61 579 vs $54 557; difference, $3003; P = .001). Spending was higher in socioeconomically deprived patients for index hospitalizations (difference, $1284; P = .005), professional services (difference, $379; P = .002), and readmissions (difference, $1188; P = .008). Inpatient rehabilitation was the only significant difference in post-acute care spending (difference, $469; P = .011). CONCLUSIONS: Medicare spending was higher for socioeconomically deprived CABG in Michigan, indicating systemic disparities over and above patient demographic factors.

Improved ultrasound image quality with pixel-based beamforming using a Wiener-filter and a SNR-dependent coherence factor.

Pixel-based beamforming generates focused data by assuming that the waveforms received on a linear transducer array are composed of spherical pulses. It does not take into account the spatiotemporal spread in the data from the length of the excitation pulse or from the transfer functions of the transducer elements. As a result, these beamformers primarily have impacts on lateral, rather than axial, resolution. This paper proposes an efficient method to improve the axial resolution for pixel-based beamforming. We extend our field pattern analysis and show that the received waveforms should be passed through a Wiener filter before being used in the coherent pixel-based beamformer. This filter is designed based on signals echoed from a single scatterer at the transmit focus. The beamformer output is then combined with a coherence factor, that is adaptive to the signal-to-noise ratio, to improve the image contrast and suppress artifacts that have arisen during the filtering process. We validate the proposed method and compare it with other beamforming strategies using a series of experiments, including simulation, phantom and in vivo studies. It is shown to offer significant improvements in axial resolution and contrast over coherent pixel-based beamforming, as well as other spatial filters derived from synthetic aperture imaging. The method also demonstrates robustness to modeling errors in the experimental data. Overall, the imaging results show that the proposed approach has the potential to be of value in clinical applications.

Gait speed is a preoperative indicator of postoperative events after elective proximal aortic surgery.

OBJECTIVE: The study objective was to evaluate whether 5-m gait speed, an established marker of frailty, is associated with postoperative events after elective proximal aortic surgery. METHODS: We performed a retrospective review of 435 patients aged more than 60 years who underwent elective proximal aortic surgery, defined as surgery on the aortic root, ascending aorta, or aortic arch through median sternotomy. Patients completed a 5-m gait speed test within 30 days before surgery. We evaluated the association between categoric (slow, ≤0.83 m/s and normal, >0.83 m/s) and continuous gait speed and the likelihood of experiencing the composite outcome before and after adjustment for European System for Cardiac Operative Risk Evaluation II. The composite outcome included in-hospital mortality, renal failure, prolonged ventilation, and discharge location. Secondary outcomes were 1-year mortality and 5-year survival. RESULTS: Of the study population, 30.3% (132/435) were categorized as slow. Slow walkers were significantly more likely to have in-hospital mortality, prolonged ventilation, and renal failure, and were less likely to be discharged home (all P < .05). The composite outcome was 2 times more likely to occur for slow walkers (gait speed categoric adjusted odds ratio, 2.08; 95% confidence interval, 1.27-3.40; P = .004). Moreover, a unit (1 m/s) increase in gait speed (continuous) was associated with 73% lower risk of experiencing the composite outcome (odds ratio, 0.27; 95% confidence interval, 0.11-0.68; P = .006). CONCLUSIONS: Slow gait speed is a preoperative indicator of risk for postoperative events after elective proximal aortic surgery. Gait speed may be an important tool to complement existing operative risk models, and its application may identify patients who may benefit from presurgical and postsurgical rehabilitation.

High Socioeconomic Deprivation and Coronary Artery Bypass Grafting Outcomes: Insights From Michigan.

BACKGROUND: Cardiovascular outcomes are worse among individuals from areas with limited socioeconomic resources. This study evaluated the relationship between high socioeconomic deprivation and isolated coronary artery bypass grafting (CABG) outcomes. METHODS: We linked statewide Society of Thoracic Surgeons Adult Cardiac Surgery Database data to Medicare Fee-for-Service records for 10 423 Michigan residents undergoing isolated CABG between January 2012 and December 2018. High socioeconomic deprivation was defined as residing in the highest decile of the ZIP Code-level area deprivation index (ADI). Multivariable logistic regression estimated the relationship between top ADI decile and major morbidity, in-hospital mortality, and operative mortality. Survival analyses evaluated long-term survival comparing patients in the top vs not in the top ADI decile. RESULTS: A total of 1036 patients were in the top decile of ADI (ADI >82.4), and they were more likely to be female, Black, and have a higher predicted risk of mortality. Patients in the top ADI decile had significantly higher rates of major morbidity (17.4% vs 11.4%; adjusted odds ratio, 1.26; 95% CI, 1.04-1.54; P = .021) and in-hospital mortality (3.2% vs 1.3%, adjusted odds ratio, 1.84; 95% CI, 1.18-2.86, P = .007) but not operative mortality. The adjusted hazard of mortality was 16% higher for patients residing in the top ADI decile (95% CI, 1.01-1.33; P = .032). CONCLUSIONS: Isolated CABG patients residing in the highest areas of socioeconomic deprivation differed with respect to demographic and clinical characteristics and experienced worse short- and long-term outcomes compared with those not in the top ADI decile.

Association of Volume and Outcomes in 234 556 Patients Undergoing Surgical Aortic Valve Replacement.

BACKGROUND: The relationship between institutional volume and operative mortality after surgical aortic valve replacement (SAVR) remains unclear. METHODS: From January 2013 to June 2018, 234 556 patients underwent isolated SAVR (n = 144 177) or SAVR with coronary artery bypass grafting (CABG) (n = 90 379) within the Society of Thoracic Surgeons Adult Cardiac Surgery Database. The association between annualized SAVR volume (group 1 [1-25 SAVRs], group 2 [26-50 SAVRs], group 3 [51-100 SAVRs], and group 4 [>100 SAVRs]) and operative mortality and composite major morbidity or mortality was assessed. Random effects models were used to evaluate whether historical (2013-2015) SAVR volume or risk-adjusted outcomes explained future (2016-2018) risk-adjusted outcomes. RESULTS: The annualized median number of SAVRs per site was 35 (interquartile range, 22-59; isolated aortic valve replacement [AVR], 20; AVR with CABG, 13). Among isolated SAVR cases, the mean operative mortality and composite morbidity or mortality were 1.5% and 9.7%, respectively, at the highest-volume sites (group 4), with significantly higher rates among progressively lower-volume groups (P trend < .001). After adjustment, lower-volume centers had increased odds of operative mortality (group 1 vs group 4 [reference]: adjusted odds ratio [AOR] for SAVR, 2.24 [95% CI, 1.91-2.64]; AOR for SAVR with CABG, 1.96 [95% CI, 1.67-2.30]) and major morbidity or mortality (AOR for SAVR, 1.53 [95% CI, 1.39-1.69]; AOR for SAVR with CABG, 1.46 [95% CI, 1.32-1.61]) compared with the highest-volume institutions. Substantial variation in outcomes was observed across hospitals within each volume category, and prior outcomes explained a greater proportion of hospital operative outcomes than did prior volume. CONCLUSIONS: Operative outcomes after SAVR with or without CABG is inversely associated with institutional procedure volumes; however, prior outcomes are more predictive of future outcomes than is prior volume. Given the excellent outcomes observed at many lower-volume hospitals, procedural outcomes may be preferable to procedural volumes as a quality metric.

Predictors of Discharge Home Without Opioids After Cardiac Surgery: A Multicenter Analysis.

BACKGROUND: Whether all patients will require an opioid prescription after cardiac surgery is unknown. We performed a multicenter analysis to identify patient predictors of not receiving an opioid prescription at the time of discharge home after cardiac surgery. METHODS: Opioid-naïve patients undergoing coronary artery bypass grafting and/or valve surgery through a sternotomy at 10 centers from January to December 2019 were identified retrospectively from a prospectively maintained data set. Opioid-naïve was defined as not taking opioids at the time of admission. The primary outcome was discharge without an opioid prescription. Mixed-effects logistic regression was performed to identify predictors of discharge without an opioid prescription, and postdischarge opioid prescribing was monitored to assess patient tolerance of discharge without an opioid prescription. RESULTS: Among 1924 eligible opioid-naïve patients, mean age was 64 ± 11 years, and 25% were women. In total, 28% of all patients were discharged without an opioid prescription. On multivariable analysis, older age, longer length of hospital stay, and undergoing surgery during the last 3 months of the study were independent predictors of discharge without an opioid prescription, whereas depression, non-Black and non-White race, and using more opioid pills on the day before discharge were independent predictors of receiving an opioid prescription. Among patients discharged without an opioid prescription, 1.8% (10 of 547) were subsequently prescribed an opioid. CONCLUSIONS: Discharging select patients without an opioid prescription after cardiac surgery appears well tolerated, with a low incidence of postdischarge opioid prescriptions. Increasing the number of patients discharged without an opioid prescription may be an area for quality improvement.

Failure to rescue: variation in mortality after cardiac surgery.

OBJECTIVES: Measures to prevent surgical complications are critical components of optimal patient care, and adequate management when complications occur is equally crucial in efforts to reduce mortality. This study aims to elucidate clinical realities underlying in-hospital variations in failure to rescue (FTR) after cardiac surgery. METHODS: Using a statewide database for a quality improvement program, we identified 62 450 patients who had undergone adult cardiac surgery between 2011 and 2018 in 1 of the 33 Michigan hospitals performing adult cardiac surgery. The hospitals were first divided into tertiles according to their observed to expected (O/E) ratios of 30-day mortality: low-mortality tertile (O/E 0.46-0.78), intermediate-mortality tertile (O/E 0.79-0.90) and high-mortality tertile (O/E 0.98-2.00). We then examined the incidence of 15 significant complications and the rates of death following complications among the 3 groups. RESULTS: A total of 1418 operative deaths occurred in the entire cohort, a crude mortality rate of 2.3% and varied from 1.3% to 5.9% at the hospital level. The death rates also diverged significantly according to mortality score tertiles, from 1.6% in the low-mortality group to 3.2% in the high-mortality group (P < 0.001). Hospitals ranked in a high- or intermediate-mortality tertile had similar rates of overall complications (21.3% and 20.7%, P = 0.17), while low-mortality hospitals had significantly fewer complications (16.3%) than the other 2 tertiles (P < 0.001). FTR increased in a stepwise manner from low- to high-mortality hospitals (8.3% vs 10.0% vs 12.7%, P < 0.001, respectively). Differences in FTR were related to survival after cardiac arrest, multi-system organ failure, prolonged ventilation, reoperation for bleeding and severe acute kidney disease that requires dialysis. CONCLUSIONS: This study demonstrates that timely recognition and appropriate treatment of complications are as important as preventing complications to further reduce operative mortality in cardiac surgery. FTR tools may provide vital information for quality improvement initiatives.

Determinants of Hospital Variation in Cardiac Rehabilitation Enrollment During Coronary Artery Disease Episodes of Care.

BACKGROUND: Cardiac rehabilitation (CR) is associated with improved outcomes for patients with coronary artery disease (CAD). However, CR enrollment remains low and there is a dearth of real-world data on hospital-level variation in CR enrollment. We sought to explore determinants of hospital variability in CR enrollment during CAD episodes of care: medical management of acute myocardial infarction (AMI-MM), percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG). METHODS: A cohort of 71 703 CAD episodes of care were identified from 33 hospitals in the Michigan Value Collaborative statewide multipayer registry (2015 to 2018). CR enrollment was defined using professional and facility claims and compared across treatment strategies: AMI-MM (n=18 678), PCI (n=41 986), and CABG (n=11 039). Hierarchical logistic regression was used to estimate effects of predictors and hospital risk-adjusted rates of CR enrollment. RESULTS: Overall, 20 613 (28.8%) patients enrolled in CR, with significant differences by treatment strategy: AMI-MM=13.4%, PCI=29.0%, CABG=53.8% (P<0.001). There were significant differences in CR enrollment across age groups, comorbidity status, and payer status. At the hospital-level, there was over 5-fold variation in hospital risk-adjusted CR enrollment rates (9.8%-51.6%). Hospital-level CR enrollment rates were highly correlated across treatment strategy, with the strongest correlation between AMI-MM versus PCI (R2=0.72), followed by PCI versus CABG (R2=0.51) and AMI-MM versus CABG (R2=0.46, all P<0.001). CONCLUSIONS: Substantial variation exists in CR enrollment during CAD episodes of care across hospitals. However, within-hospital CR enrollment rates were significantly correlated across all treatment strategies. These findings suggest that CR enrollment during CAD episodes of care is the product of hospital-specific rather than treatment-specific practice patterns.