Variation in cost-effectiveness in coronary revascularization: a new paradigm for evaluation?

PURPOSE OF REVIEW: Cost-effectiveness has become an increasingly important tool in assessing the value of healthcare. The principles of cost-effectiveness and the need to standardize the methodology are discussed. Documented variation could be used to adjust reimbursement. RECENT FINDINGS: The US healthcare system continues to be under financial pressure. Although national health expenditures have slowed, growth rates continue to outpace gross domestic product. Spending in the coming years is expected to grow 7% annually. Treatment of cardiac disease, and in particular ischemic heart disease, is a significant portion of healthcare spending. A strategy to improve clinical and financial outcomes for revascularization procedures is essential. Recently, the SYNTAX trial and ASCERT have addressed cost-effectiveness as an outcome measure in revascularization for coronary artery disease. SUMMARY: Cost-effectiveness is becoming an important part of healthcare provider performance and patient outcomes. Difficulties in obtaining cost, resource use, and quality of life data are not insurmountable as recently documented in randomized and observational trials. Reimbursement has already been linked to costs and resource use in current regulation. As the payment systems move toward disease management, cost-effectiveness will be the measure of choice. The prevalence of cardiac disease in the US population will mandate its use in adjusting payments to these providers.

Effect of Socioeconomic Distress on Risk-Adjusted Mortality After Valve Surgery for Infective Endocarditis.

Infective endocarditis affects patients of all socioeconomic status. We hypothesized that the Distressed Communities Index (DCI), a comprehensive assessment of socioeconomic status, would be associated with risk-adjusted mortality for patients with endocarditis. All patients with endocarditis (2001-2017) in a regional Society of Thoracic Surgeons database were analyzed. DCI scores range from 0 (no socioeconomic distress) to 100 (severe distress) and account for unemployment, poverty rate, median income, housing vacancies, education level, and business growth by zip code. The most distressed patients (top quartile, DCI > 75) were compared to all other patients. Hierarchical logistic regression modeled the association between DCI and mortality. A total of 2,075 patients were included (median age 55 years, 65.2% urgent/emergent cases, 42.7% self-pay). Major morbidity was 32.8% and operative mortality was 9.5%. Tricuspid/pulmonic valve endocarditis was present in 12.5% of cases, with significantly worse mean DCI compared to patients with left-sided endocarditis (median 55.3, IQR 20.3-77.6 vs 46.8, IQR 17.3-74.2, P = 0.016). High socioeconomic distress (DCI > 75) was associated with higher rates of major morbidity, operative mortality, increased length of stay, and higher total cost. After risk-adjustment, DCI was independently predictive of higher operative mortality for patients with endocarditis (OR 1.24 per DCI quartile increase, 95% CI 1.06-1.45, P < 0.001). Increasing DCI, an indicator of poor socioeconomic status, independently predicts increased risk-adjusted mortality and resource utilization for patients with endocarditis. Accounting for socioeconomic status allows for more accurate risk prediction and resource allocation for patients with endocarditis.

Socioeconomic Distress Associated With Increased Use of Percutaneous Coronary Intervention Over Coronary Artery Bypass Grafting.

BACKGROUND: The influence of socioeconomic determinants of health on choice of percutaneous coronary intervention (PCI) vs coronary artery bypass grafting (CABG) for coronary artery disease is unknown. We hypothesized that higher Distressed Communities Index (DCI) scores, a comprehensive socioeconomic ranking by zip code, would be associated with more frequent PCI. METHODS: All patients undergoing isolated CABG or PCI in a regional American College of Cardiology CathPCI registry and The Society of Thoracic Surgeons database (2018-2021) were assigned DCI scores (0 = no distress, 100 = severe distress) based on education level, poverty, unemployment, housing vacancies, median income, and business growth. Patients who presented with ST-segment elevation myocardial infarction or emergent procedures were excluded. The most distressed quintile (DCI ≥80) was compared with all other patients. Multivariable logistic regression analyzed the association between DCI and procedure type. RESULTS: A total of 23 223 patients underwent either PCI (n = 16 079) or CABG (n = 7144) for coronary artery disease across 28 centers during the study period. Before adjustment, high socioeconomic distress occurred more frequently among CABG patients (DCI ≥80, 12.4% vs 8.42%; P < .001). After multivariable adjustment, high socioeconomic distress was associated with greater odds of receiving PCI, relative to CABG (odds ratio 1.26; 95% CI, 1.07-1.49; P = .007). High socioeconomic distress was significantly associated with postprocedural mortality (odds ratio 1.52; 95% CI, 1.02-2.26; P = .039). CONCLUSIONS: High socioeconomic distress is associated with greater risk-adjusted odds of receiving PCI, relative to CABG, as well as higher postprocedural mortality. Targeted resource allocation in high DCI areas may help eliminate barriers to CABG.

Center case volume is associated with Society of Thoracic Surgeons-defined failure to rescue in cardiac surgery.

OBJECTIVE: Our understanding of the impact of a center's case volume on failure to rescue (FTR) after cardiac surgery is incomplete. We hypothesized that increasing center case volume would be associated with lower FTR. METHODS: Patients undergoing a Society of Thoracic Surgeons index operation in a regional collaborative (2011-2021) were included. After we excluded patients with missing Society of Thoracic Surgeons Predicted Risk of Mortality scores, patients were stratified by mean annual center case volume. The lowest quartile of case volume was compared with all other patients. Logistic regression analyzed the association between center case volume and FTR, adjusting for patient demographics, race, insurance, comorbidities, procedure type, and year. RESULTS: A total of 43,641 patients were included across 17 centers during the study period. Of these, 5315 (12.2%) developed an FTR complication, and 735 (13.8% of those who developed an FTR complication) experienced FTR. Median annual case volume was 226, with 25th and 75th percentile cutoffs of 136 and 284 cases, respectively. Increasing center-level case volume was associated with significantly greater center-level major complication rates but lower mortality and FTR rates (all P values < .01). Observed-to-expected FTR was significantly associated with case volume (P = .040). Increasing case volume was independently associated with decreasing FTR rate in the final multivariable model (odds ratio, 0.87 per quartile; confidence interval, 0.799-0.946, P = .001). CONCLUSIONS: Increasing center case volume is significantly associated with improved FTR rates. Assessment of low-volume centers' FTR performance represents an opportunity for quality improvement.

Implications of Methicillin-Resistant Staphylococcus aureus Carriage on Cardiac Surgical Outcomes.

BACKGROUND: Staphylococcus aureus remains the most common cause of sternal surgical site infections (SSIs). Opinions on the postoperative implications of preoperative methicillin-resistant S aureus (MRSA) colonization currently differ. This study aimed to investigate whether MRSA carriage affects postoperative outcomes and safety of operation. METHODS: A total of 1,774,811 cardiac surgical patients from 2009 to 2014 were identified from the National Inpatient Sample database. Among these patients, 5798 (0.33%) were MRSA carriers. Propensity-score matching was used to determine the effect of MRSA colonization on outcomes. RESULTS: MRSA carriers did not differ in age or sex from noncarriers, but they more often presented for urgent surgery (P < .001). Among matched pairs, there was no difference in mortality (P = .76), stroke, SSIs, pneumonia, renal failure, cardiac complications, respiratory failure, or prolonged mechanical ventilation. MRSA infection (P < .001), MRSA septicemia (P = 0.03), and blood transfusion (P = .003) occurred more often among MRSA carriers. There was no increase in cost (P = .12), but the hospital length of stay was longer (P = .005). Predictors of MRSA infection among carriers included age older than 85 years, rural hospital location, and diabetes. Carriers with endocarditis and drug abuse were at highest risk for MRSA infection. CONCLUSIONS: MRSA carriers undergoing cardiac surgery are not at higher risk for mortality or SSIs and can expect outcomes similar to those of noncarriers. Higher rates of postoperative MRSA infection and septicemia among carriers, although still very low, support the need for selective preoperative screening and prophylaxis when possible.

Risk Aversion in Cardiac Surgery: 15-Year Trends in a Statewide Analysis.

BACKGROUND: With a rising emphasis on public reporting, we hypothesized that select hospitals are becoming increasingly risk-averse by avoiding high-risk operations. Further, we evaluated the association between risk-averse practices, outcomes, and publicly reported quality measures. METHODS: Clinical data from 78,417 patients undergoing cardiac surgery (2002-2016) from a regional consortium was paired with publicly available reimbursement and quality data. High-risk surgery was defined as predicted risk of mortality ≥5%. Hospital risk aversion was defined as a significant decrease in both high-risk volume and proportion, with cases stratified by hospital risk aversion status for univariate analysis. RESULTS: The rate of high-risk cases decreased from 17.9% in 2002 to 12.6% in 2016. Significant risk aversion was seen in 39% of hospitals, which had a 59% decrease in high-risk volume vs a 16% decrease at non-risk-averse hospitals. In the last 5 years, declining high-risk cases at risk-averse hospitals were driven by fewer cases from transfers (19.2% vs 28.1%, P < .001) and the emergency department (17.6% vs 19.2%, P = .001). Only non-risk-averse hospitals had mortality rates lower than expected (risk-averse: 0.97 [95% confidence interval, 0.91-1.03], P = .30; non-risk-averse: 0.88 [95% confidence interval, 0.83-0.94], P = .001). There were no differences by risk aversion status in reported ratings or financial incentives (all P > .05). CONCLUSIONS: Over 60% of hospitals continue to operate on high-risk patients, with concentration of care driven by transfer patterns. These non-risk-averse hospitals are high-performing with better-than-expected outcomes, particularly in high-risk cases. Transparency and objectivity in reporting are essential to ensure continued access for these high-risk patients.

Impact of transfer status on real-world outcomes in nonelective cardiac surgery.

OBJECTIVE: Transfer from hospital to hospital for cardiac surgery represents a large portion of some clinical practices. Previous literature in other surgical fields has shown worse outcomes for transferred patients. We hypothesized that transferred patients would be higher risk and demonstrate worse outcomes than those admitted through the emergency department. METHODS: All patients undergoing cardiac operations with a Society of Thoracic Surgeons Predicted Risk of Mortality were evaluated from a multicenter, statewide Society of Thoracic Surgeons database. Only patients requiring admission before surgery were included. Patients were stratified by admission through the emergency department or in transfer. Transfers were further stratified by the cardiothoracic surgery capabilities at the referring center. RESULTS: A total of 13,094 patients met the inclusion criteria of admission before surgery. This included 7582 (57.9%) transfers, of which 502 (6.6%) were referred from cardiac centers. Compared with emergency department admissions, transfers had increased hospital costs despite lower operative risk (Predicted Risk of Mortality 1.5% vs 1.6%, P < .01) and equivalent postoperative morbidity (15.6% vs 15.3% P = .63). In risk-adjusted analysis, transfer status was not independently associated with worse outcomes. Patients transferred from centers that perform cardiac surgery are higher risk than general transfers (Predicted Risk of Mortality 2.5% vs 1.5, P < .01), but specialized care results in excellent risk-adjusted outcomes (observed/expected: mortality 0.81; morbidity or mortality 0.90). CONCLUSIONS: Transfer patients have similar rates of postoperative complications but increased resource use compared with patients admitted through the emergency department. Patients transferred from centers that perform cardiac surgery represent a particularly high-risk subgroup.

Examination of a Proposed 30-day Readmission Risk Score on Discharge Location and Cost.

BACKGROUND: Readmissions cost an estimated $41 billion in the United States each year. To address this, a single institution recently developed a new risk model predictive of 30-day readmission after adult cardiac surgery. The purpose of this study is to validate and refine this new readmission risk model using a statewide database. METHODS: A total of 19,964 patients were analyzed using a statewide Society of Thoracic Surgeons database (2014-2017). The aforementioned multivariate model was replicated (model 1): race, hospital length of stay, chronic lung disease, operation type, and renal failure. Model 2 also included discharge location. Thirty-day readmission risk scores and low-risk (0%-10%), moderate-risk (10%-13%), and high-risk (≥13%) categories were calculated. RESULTS: The overall 30-day readmission rate was 11.1% with both models 1 and 2 predicting readmission (odds ratio, 1.09; 95% confidence interval, 1.08-1.11 vs odds ratio, 1.10; 95% confidence interval, 1.08-1.11). Statistically significant differences were observed across all risk categories in discharge location and total cost. For models 1 and 2, 86% of low-risk patients were discharged to home vs 66.9% and 42.9% of patients in high-risk groups, respectively (P < .001). The largest increases were observed with a hospice discharge location for both model 1 (from $37,930 to $89,285) and model 2 (from $37,930 to $89,230). CONCLUSIONS: Both risk models significantly predicted 30-day readmission in our multiinstitutional dataset, confirming the score is valid and a generalizable quality improvement tool. The addition of discharge location and total cost adds valuable information of the ongoing efforts to identify patients at high risk for readmission.

Current quality reporting methods are not adequate for salvage cardiac operations.

OBJECTIVES: Outcomes in cardiac surgery are benchmarked against national Society of Thoracic Surgeons (STS) data and include patients undergoing elective, urgent, emergent, and salvage operations. This practice relies on accurate risk adjustment to avoid risk-averse behavior. We hypothesize that the STS risk calculator does not adequately characterize the risk of salvage operations because of their heterogeneity and infrequent occurrence. METHODS: Data on all cardiac surgery patients with an STS predicted risk score (2002-2017) were extracted from a regional database of 19 cardiac surgery centers. Patients were stratified according to operative status for univariate analysis. Observed-to-expected (O:E) ratios for mortality and composite morbidity/mortality were calculated and compared among elective, urgent, emergent, and salvage patients. RESULTS: A total of 76,498 patients met inclusion criteria. The O:E mortality ratios for elective, urgent, and emergent cases were 0.96, 0.98, and 0.93, respectively (all P values > .05). However, mortality rate was significantly higher than expected for salvage patients (O:E ratio, 1.41; P = .04). Composite morbidity/mortality rate was lower than expected in elective (O:E ratio, 0.81; P = .0001) and urgent (O:E ratio, 0.93; P = .0001) cases but higher for emergent (O:E ratio, 1.13; P = .0006) and salvage (O:E ratio, 1.24; P = .01). O:E ratios for salvage mortality were highly variable among each of the 19 centers. CONCLUSIONS: The current STS risk models do not adequately predict outcomes for salvage cardiac surgery patients. On the basis of these results, we recommend more detailed reporting of salvage outcomes to avoid risk aversion in these potentially life-saving operations.

Regional collaboration as a model for fostering accountability and transforming health care.

An era of increasing budgetary constraints, misaligned payers and providers, and a competitive system where United States health outcomes are outpaced by less well-funded nations is motivating policy-makers to seek more effective means for promoting cost-effective delivery and accountability. This article illustrates an effective working model of regional collaboration focused on improving health outcomes, containing costs, and making efficient use of resources in cardiovascular surgical care. The Virginia Cardiac Surgery Quality Initiative is a decade-old collaboration of cardiac surgeons and hospital providers in Virginia working to improve outcomes and contain costs by analyzing comparative data, identifying top performers, and replicating best clinical practices on a statewide basis. The group's goals and objectives, along with 2 generations of performance improvement initiatives, are examined. These involve attempts to improve postoperative outcomes and use of tools for decision support and modeling. This work has led the group to espouse a more integrated approach to performance improvement and to formulate principles of a quality-focused payment system. This is one in which collaboration promotes regional accountability to deliver quality care on a cost-effective basis. The Virginia Cardiac Surgery Quality Initiative has attempted to test a global pricing model and has implemented a pay-for-performance program where physicians and hospitals are aligned with common objectives. Although this collaborative approach is a work in progress, authors point out preconditions applicable to other regions and medical specialties. A road map of short-term next steps is needed to create an adaptive payment system tied to the national agenda for reforming the delivery system.

Model for End-Stage Liver Disease Score Independently Predicts Mortality in Cardiac Surgery.

BACKGROUND: Although liver disease increases surgical risk, it is not considered in The Society for Thoracic Surgeons (STS) risk calculator. This study assessed the impact of Model for End-Stage Liver Disease (MELD) on outcomes after cardiac surgical procedures and the additional predictive value of MELD in the STS risk model. METHODS: Deidentified records of 21,272 patients were extracted from a regional STS database. Inclusion criteria were any cardiac operation with a risk score available (2011-2016). Exclusion criteria included missing MELD (n = 2,895) or preoperative anticoagulation (n = 144). Patients were stratified into three categories, MELD < 9 (low), MELD 9 to 15 (moderate), and MELD > 15 (high). Univariate and multivariate logistic regression assessed risk-adjusted associations between MELD and operative outcomes. RESULTS: Increasing MELD scores were associated with greater comorbid disease, mitral operation, prior cardiac operation, and higher STS-predicted risk of mortality (1.1%, 2.3%, and 6.0% by MELD category; p < 0.0001). The operative mortality rate increased with increasing MELD score (1.6%, 3.9%, and 8.4%; p < 0.0001). By logistic regression MELD score was an independent predictor of operative mortality (odds ratio, 1.03 per MELD score point; p < 0.0001) as were the components total bilirubin (odds ratio, 1.22 per mg/dL; p = 0.002) and international normalized ratio (odds ratio, 1.40 per unit; p < 0.0001). Finally, MELD score was independently associated with STS major morbidity and the component complications renal failure and stroke. CONCLUSIONS: Increasing MELD score, international normalized ratio, and bilirubin all independently increase risk of operative mortality. Because high rates of missing data currently limit utilization of MELD, efforts to simplify and improve data collection would help improve future risk models.

Is routine extubation overnight safe in cardiac surgery patients?

OBJECTIVES: Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database. METHODS: Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00. RESULTS: A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality. CONCLUSIONS: Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.

Incremental Risk of Annular Enlargement: A Multi-Institutional Cohort Study.

BACKGROUND: Annular enlargement (AE) is a critical technique to avoid patient-prosthesis mismatch and may help facilitate future valve-in-valve (ViV) transcatheter replacement. We hypothesized that the addition of annular enlargement would increase risk of morbidity and mortality and that the number of annular enlargement procedures is increasing to accommodate future ViV procedures. METHODS: Patients undergoing aortic valve replacement ± coronary surgery (2012 to 2017) were extracted from a regional Society of Thoracic Surgeons database. Patients were stratified by annular enlargement and era, pre-ViV (2012 to 2014) vs ViV (2015 to 2017) for univariate analysis. Risk-adjusted outcomes were assessed by hierarchical regression modeling adjusting for predicted risk of mortality. RESULTS: Of 6045 patients, the 300 (5.0%) who received an annular enlargement were younger and more commonly female. Patients receiving an annular enlargement had higher complication rates including operative mortality (4.7% vs 2.5%, P = .024). After risk adjustment, AE was independently associated with increased mortality (odds ratio, 2.06, P = .016) and major morbidity (odds ratio, 1.41, P = .042). The rate of enlargement increased from 3.9% pre-ViV to 6.3% ViV (P < .001). The use of ViV capable valves (bioprosthetic ≥23 mm) from 61% to 67% (P = .001), and more in AE patients (30% vs 11% non-AE). Alternatively, the rate of patient prosthesis mismatch declined from 23% to 16%. CONCLUSIONS: Increasing utilization of AE coincides with a decline in patient prosthesis mismatch and may facilitate future ViV transcatheter aortic valve replacement. However, AE was independently associated with increased morbidity and mortality. High variability in AE volume may be increasing risk and deserves further investigation.

Socioeconomic Distressed Communities Index Predicts Risk-Adjusted Mortality After Cardiac Surgery.

BACKGROUND: The effects of socioeconomic factors other than insurance status and race on outcomes after cardiac operations are not well understood. We hypothesized that the Distressed Communities Index (DCI), a comprehensive socioeconomic ranking by zip code, would predict operative mortality after coronary artery bypass grafting (CABG). METHODS: All patients who underwent isolated CABG (2010 to 2017) in the Virginia Cardiac Services Quality Initiative database were analyzed. The DCI accounts for unemployment, education level, poverty rate, median income, business growth, and housing vacancies, with scores ranging from 0 (no distress) to 100 (severe distress). Patients were stratified by DCI quartiles (I: 0 to 24.9, II: 25 to 49.9, III: 50 to 74.9, IV: 75 to 100) and compared. Hierarchical linear regression modeled the association between the DCI and mortality. RESULTS: A total of 19,756 CABG patients were analyzed, with mean predicted risk of mortality of 2.0% ± 3.5%. Higher DCI scores were associated with increasing predicted risk of mortality. Overall operative mortality was 2.1% (n = 424) and increased with increasing DCI quartile (I: 1.6% [n = 95], II: 2.1% [n = 77], III: 2.4% [n = 114], IV: 2.6% [n = 138]; p = 0.0009). The observed-to-expected ratio for mortality increased as level of socioeconomic distress increased. After risk adjustment for The Society of Thoracic Surgeons predicted risk of mortality, year of surgical procedure, and hospital, the DCI remained predictive of operative mortality after CABG (odds ratio, 1.14 for each 25-point increase in DCI; 95% confidence interval 1.04 to 1.26; p = 0.007). CONCLUSIONS: The DCI independently predicts risk-adjusted operative mortality after CABG. Socioeconomic status, although not part of traditional risk calculators, should be considered when building risk models, evaluating resource utilization, and comparing hospitals.

Impact of Regional Collaboration on Quality Improvement and Associated Cost Savings in Coronary Artery Bypass Grafting.

BACKGROUND: A statewide database identified prolonged ventilation (PV) and acute renal failure (RF) as the biggest cost drivers after isolated coronary artery bypass grafting. Reducing these complications through regional collaboration should improve outcomes and lower health care costs. METHODS: A total of 27,978 patients who underwent isolated coronary artery bypass grafting were divided into pre- and post-quality improvement initiative groups (early era: 2008 to 2011, n = 15,176; later era: 2012 to 2015, n = 12,802). Focused learning sessions on PV and postoperative RF were undertaken in the earlier era. Incidence of death, PV, and RF in the two groups was analyzed using one-way analysis of variance and Fisher exact tests. RESULTS: The Society of Thoracic Surgeons (STS) predicted risk of mortality and predicted risk of mortality/morbidity were significantly higher in the later era (p < 0.01), as were STS predicted PV (10.1% vs 11.3%) and RF (3.4% vs 3.8%). Despite these increased risks, STS observed-to-expected ratios for mortality and mortality/morbidity fell. Observed rates for PV (10.5% vs 8.8%, p < 0.01) and RF (3.6% vs 2.3%, p < 0.01) were associated with STS observed-to-expected ratios of PV (1.04 vs 0.78) and RF (1.03 vs 0.60). Adjusting for case volume in the two eras, 271 cases of PV and 170 of RF were avoided, with estimated cost savings of $10,212,637 and $8,519,630, respectively. CONCLUSIONS: A regional collaboration using a statewide STS and an all-payor database with focused quality improvement is a powerful tool for change. Despite rising risks for mortality and morbidity, outcomes for PV and RF improved and produced significant cost savings. Applying these efforts nationally can enormously affect patient care and health care costs.

Postoperative atrial fibrillation is associated with increased morbidity and resource utilization after left ventricular assist device placement.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a known risk factor for morbidity and mortality after cardiac surgery but has not been investigated in the left ventricular assist device (LVAD) population. We hypothesize that POAF will increase morbidity and resource utilization after LVAD placement. METHODS: Records were extracted for all patients in a regional database who underwent continuous-flow LVAD placement (n = 1064, 2009-2017). Patients without a history of atrial fibrillation (n = 689) were stratified by POAF for univariate analysis. Multivariable regression models calculated the risk-adjusted association of arrhythmias on outcomes and resource utilization. RESULTS: The incidence of new-onset POAF was 17.6%, and patients who developed POAF were older and more likely to have moderate/severe mitral regurgitation, a history of stroke, and concomitant tricuspid surgery. After risk adjustment, POAF was not associated with operative mortality or stroke but was associated with major morbidity (odds ratio [OR] 2.5 P = .0004), prolonged ventilation (OR 2.7, P < .0001), unplanned right ventricular assist device (OR 2.9, P = .01), and a trend toward renal failure (OR 2.0, P = .06). In addition, POAF was associated with greater risk-adjusted resource utilization, including discharge to a facility (OR 2.2, P = .007), an additional 4.9 postoperative days (P = .02), and 88 hours in the intensive care unit (P = .01). CONCLUSIONS: POAF was associated with increased major morbidity, possibly from worsening right heart failure leading to increased renal failure and unplanned right ventricular assist device placement. This led to patients with POAF having longer intensive care unit and hospital stays and more frequent discharges to a facility.

Preoperative anemia versus blood transfusion: Which is the culprit for worse outcomes in cardiac surgery?

BACKGROUND: Reducing blood product utilization after cardiac surgery has become a focus of perioperative care as studies have suggested improved outcomes. The relative impact of preoperative anemia versus packed red blood cells (PRBC) transfusion on outcomes remains poorly understood, however. In this study, we investigated the relative association between preoperative hematocrit (Hct) level and PRBC transfusion on postoperative outcomes after coronary artery bypass grafting (CABG) surgery. METHODS: Patient records for primary, isolated CABG operations performed between January 2007 and December 2017 at 19 cardiac surgery centers were evaluated. Hierarchical logistic regression modeling was used to estimate the relationship between baseline preoperative Hct level as well as PRBC transfusion and the likelihoods of postoperative mortality and morbidity, adjusted for baseline patient risk. Variable and model performance characteristics were compared to determine the relative strength of association between Hct level and PRBC transfusion and primary outcomes. RESULTS: A total of 33,411 patients (median patient age, 65 years; interquartile range [IQR], 57-72 years; 26% females) were evaluated. The median preoperative Hct value was 39% (IQR, 36%-42%), and the mean Society of Thoracic Surgeons (STS) predicted risk of mortality was 1.8 ± 3.1%. Complications included PRBC transfusion in 31% of patients, renal failure in 2.8%, stroke in 1.3%, and operative mortality in 2.0%. A strong association was observed between preoperative Hct value and the likelihood of PRBC transfusion (P < .001). After risk adjustment, PRBC transfusion, but not Hct value, demonstrated stronger associations with postoperative mortality (odds ratio [OR], 4.3; P < .0001), renal failure (OR 6.3; P < .0001), and stroke (OR, 2.4; P < .0001). A 1-point increase in preoperative Hct was associated with decreased probabilities of mortality (OR, 0.97; P = .0001) and renal failure (OR, 0.94; P < .0001). The models with PRBC had superior predictive power, with a larger area under the curve, compared with Hct for all outcomes (all P < .01). Preoperative anemia was associated with up to a 4-fold increase in the probability of PRBC transfusion, a 3-fold increase in renal failure, and almost double the mortality. CONCLUSIONS: PRBC transfusion appears to be more closely associated with risk-adjusted morbidity and mortality compared with preoperative Hct level alone, supporting efforts to reduce unnecessary PRBC transfusions. Preoperative anemia independently increases the risk of postoperative morbidity and mortality. These data suggest that preoperative Hct should be included in the STS risk calculators. Finally, efforts to optimize preoperative hematocrit should be investigated as a potentially modifiable risk factor for mortality and morbidity.

Development of a Risk Prediction Model and Clinical Risk Score for Isolated Tricuspid Valve Surgery.

BACKGROUND: Although tricuspid valve operations remain associated with high mortality (approximately 8% to 10%), no robust prediction models exist to support clinical decision making. We developed a preoperative clinical risk model with an easily calculable clinical risk score (CRS) to predict mortality and major morbidity after isolated tricuspid valve surgery. METHODS: The Society of Thoracic Surgeons database records were evaluated for 2,050 isolated TV repair and replacement operations for any etiology performed at 50 hospitals (2002 to 2014) in a number of states. Parsimonious preoperative risk prediction models were developed using multiple-level mixed effects regression to estimate mortality and composite major morbidity risk. Model results were utilized to establish a novel CRS for patients undergoing tricuspid valve operations. Models were evaluated for discrimination and calibration. RESULTS: Operative mortality and composite major morbidity rates were 9% and 42%, respectively. Final regression models performed well (both p < 0.001; areas under the receiver-operating characteristics curve 0.74 and 0.76) and included preoperative factors: age, sex, stroke, hemodialysis, ejection fraction, lung disease, New York Heart Association class, reoperation, and urgent or emergency status (all p < 0.05). A simple CRS from 0 to 10+ was highly associated (p < 0.001) with incremental increases in predicted mortality and major morbidity. Predicted mortality risk ranged from 2% to 34% across CRS categories, and predicted major morbidity risk ranged from 13% to 71%. CONCLUSIONS: Mortality and major morbidity after isolated tricuspid valve surgery can be predicted using preoperative patient data from The Society of Thoracic Surgeons National Adult Cardiac Database. A simple clinical risk score predicts mortality and major morbidity after isolated tricuspid valve surgery. This score may facilitate perioperative counseling and identification of suitable patients for tricuspid valve surgery.

Outcomes for Low-Risk Surgical Aortic Valve Replacement: A Benchmark for Aortic Valve Technology.

BACKGROUND: Two large, randomized trials are underway evaluating transcatheter aortic valve replacement (AVR) against conventional surgical AVR. We analyzed contemporary, real-world outcomes of surgical AVR in low-risk patients to provide a practical benchmark of outcomes and cost for evaluating current and future transapical AVR technology. METHODS: From 2010 to 2015, 2,505 isolated AVR operations were performed for severe aortic stenosis at 18 statewide cardiac institutions. Of these, 2,138 patients had a Society of Thoracic Surgeons predicted risk of mortality of less than 4%, and 1,119 met other clinical and hemodynamic criteria as outlined in the PARTNER 3 (The Placement of Transcatheter Aortic Valves) protocol. Patients with endocarditis, end-stage renal disease, ejection fraction of less than 0.45, bicuspid valves, and previous valve replacements were excluded. Outcomes of interest included operative death and postoperative adverse events. RESULTS: The median Society of Thoracic Surgeons predicted risk of mortality for the study-eligible patients was 1.44%, with a median age of 72 years (interquartile range [IQR], 65 to 78 years). Operative mortality was 1.3%, permanent stroke was 1.3%, and pacemaker requirement was 4.2%. The most common adverse events were transfusion of 2 or more units of red blood cells (18%) and atrial fibrillation (28%). The median length of stay was 6 days (IQR, 5 to 8 days). Median total hospital cost was $37,999 (IQR, $30,671 to $46,138). Examination of complications by age younger than 65 vs 65 or older demonstrated a significantly lower need for transfusion (11.2%, p < 0.001) and incidence of atrial fibrillation (17.1%, p < 0.001) but no difference in operative mortality (2.2% vs 0.9%, p = 0.1), major morbidity (10.4% vs 12.6%, p = 0.3), or total hospital costs. CONCLUSIONS: Low-risk patients undergoing surgical AVR in the current era have excellent results. The most common complications were atrial fibrillation and bleeding. These real-world results should provide additional context for upcoming transcatheter clinical trial data.

Impact of Transcatheter Technology on Surgical Aortic Valve Replacement Volume, Outcomes, and Cost.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) represents a disruptive technology that is rapidly expanding in use. We evaluated the effect on surgical aortic valve replacement (SAVR) patient selection, outcomes, volume, and cost. METHODS: A total of 11,565 patients who underwent SAVR, with or without coronary artery bypass grafting (2002 to 2015), were evaluated from the Virginia Cardiac Services Quality Initiative database. Patients were stratified by surgical era: pre-TAVR era (2002 to 2008, n = 5,113), early-TAVR era (2009 to 2011, n = 2,709), and commercial-TAVR era (2012 to 2015, n = 3,743). Patient characteristics, outcomes, and resource utilization were analyzed by univariate analyses. RESULTS: Throughout the study period, statewide SAVR volumes increased with median volumes of pre-TAVR: 722 cases/year, early-TAVR: 892 cases/year, and commercial-TAVR: 940 cases/year (p = 0.005). Implementation of TAVR was associated with declining Society of Thoracic Surgeons predicted risk of mortality among SAVR patients (3.7%, 2.6%, and 2.4%; p < 0.0001), despite increasing rates of comorbid disease. The mortality rate was lowest in the current commercial-TAVR era (3.9%, 4.3%, and 3.2%; p = 0.05), and major morbidity decreased throughout the time period (21.2%, 20.5%, and 15.2%; p < 0.0001). The lowest observed-to-expected ratios for both occurred in the commercial-TAVR era (0.9 and 0.9, respectively). Resource utilization increased generally, including total cost increases from $42,835 to $51,923 to $54,710 (p < 0.0001). CONCLUSIONS: At present, SAVR volumes have not been affected by the introduction of TAVR. The outcomes for SAVR continue to improve, potentially due to availability of transcatheter options for high-risk patients. Despite rising costs for SAVR, open approaches still provide a significant cost advantage over TAVR.