Statewide data on surgical ablation for atrial fibrillation: The data provide a path forward

OBJECTIVE

Atrial fibrillation (AF), if left untreated, is associated with increased intermediate and long-term morbidity/mortality. Surgical treatment for AF is lacking standardization in patient selection and lesion set, despite clear support from multi-society guidelines. The aim of this study was to analyze a statewide cardiac surgery registry to establish whether or not there is an association between center volume and type of index procedure with performance of surgical ablation (SA) for AF, the lesion set chosen, and ablation technology used.

METHODS

Adult, first-time, nonemergency patients with preoperative AF between 2014 and 2022 excluding standalone SA procedures from a statewide registry of Society of Thoracic Surgeons data were included (N = 4320). AF treatment variability by hospital volume (ordered from smallest to largest) and surgery type were examined with χ2 analyses. Hospital-level Spearman correlations compared hospital volume with proportion of AF patients treated with SA.

RESULTS

Overall, 37% of patients with AF were ablated at the time of surgery (63% of mitral procedures, 26% of non-mitrals) and 15% had left atrial appendage management only. There was a significant temporal trend of increasing performance of SA for AF over time (Cochran-Armitage = 27.8; P < .001). Hospital cardiac surgery volume did not correlate with the proportion of AF patients treated with SA (rs = 0.19; P = .603) with a rate of SA below the state average for academic centers. Of cases with SA (n = 1582), only 43% had a biatrial lesion set. Procedures that involved mitral surgery were more likely to include a biatrial lesion set (χ2 = 392.3; P < .001) for both paroxysmal and persistent AF. Similarly, ablation technology use was variable by type of concomitant operation (χ2 = 219.0; P < .001) such that radiofrequency energy was more likely to be used in non-mitral procedures.

CONCLUSIONS

These results indicate an increase in adoption of SA for AF over time. No association between greater hospital volume or academic status and performance of SA for AF was established. Similar to national data, the type of index procedure remains the most consistent factor in the decision to perform SA with a disconnect between AF pathophysiology and decision making on the type of SA performed. This analysis demonstrates a gap between evidence-based guidelines and real-world practice, highlighting an opportunity to confer the benefits of concomitant SA to more patients.

Trends in the Use of Recombinant Activated Factor VII and Prothrombin Complex Concentrate in Heart Transplant Patients in Virginia

OBJECTIVES

To explore trends in intraoperative procoagulant factor concentrate use in patients undergoing heart transplantation (HTx) in Virginia. Secondarily, to evaluate their association with postoperative thrombosis.

DESIGN

Patients who underwent HTx were identified using a statewide database. Trends in off-label recombinant activated factor VII (rFVIIa) use and on-label and off-label prothrombin complex concentrate (PCC) use were tested using the Mantel-Haenszel test. Multivariate logistic regression was used to test for an association between procoagulant factor concentrate administration and thrombosis.

SETTING

Virginia hospitals performing HTx.

PARTICIPANTS

Adults undergoing HTx between 2012 and 2022.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Among 899 patients who required HTx, 100 (11.1%) received off-label rFVIIa, 69 (7.7%) received on-label PCC, and 80 (8.9%) received off-label PCC. There was a downward trend in the use of rFVIIa over the 10-year period (p = 0.04). There was no trend in on-label PCC use (p = 0.12); however, there was an increase in off-label PCC use (p < 0.001). Patients who received rFVIIa were transfused more and had longer cardiopulmonary bypass time (p < 0.001). Receipt of rFVIIa was associated with increased thrombotic risk (odds ratio [OR] 1.92; 95% CI 1.12-3.29; p = 0.02), whereas on-label and off-label PCC use had no association with thrombosis (OR 0.98, 95% CI 0.49-1.96, p = 0.96 for on-label use; and OR 0.61, 95% CI 0.29-1.30, p = 0.20 for off-label use).

CONCLUSIONS

Use of rFVIIa in HTx decreased over the past decade, whereas off-label PCC use increased. Receipt of rFVIIa was associated with thrombosis; however, patients who received rFVIIa were more severely ill, and risk adjustment may have been incomplete.

Unexpected impact of preoperative anemia in low-risk isolated coronary artery bypass grafting or single-valve surgical patients: Do not overlook these patients in anemia management!

OBJECTIVE

Preoperative anemia is prevalent in cardiac surgery and independently associated with increased risk for short-term and long-term mortality. The purpose of this study was to examine the effect of preoperative hematocrit (Hct) on outcomes in cardiac surgical patients and whether the effect is comparable across levels of Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM).

METHODS

The study consisted of adult, isolated coronary artery bypass grafting (CABG) or single-valve surgical patients in a statewide registry from 2011 to 2022 (N = 29,828). Regressions were used to assess effect of preoperative Hct on STS-defined major morbidity/mortality including the interaction of Hct and STS PROM as continuous variables.

RESULTS

Median age was 66 years (58-73 years), STS PROM was 1.02% (0.58%-1.99%), and preoperative Hct was 39.5% (35.8%-42.8%). The sample consisted of 78% isolated CABG (n = 23,261), 10% isolated mitral valve repair/replacement (n = 3119), 12% isolated aortic valve replacement (n = 3448), and 29% were female (n = 8646). Multivariable analyses found that greater Hct was associated with reduced risk of STS-defined morbidity/mortality (odds ratio, 0.96; P < .001). These effects for Hct persisted even after adjustment for intraoperative blood transfusion. The interaction of Hct and STS PROM was significant for morbidity/mortality (odds ratio, 1.01; P < .001). There was a stronger association between Hct levels and morbidity/mortality risk in the patients with the lowest STS risk compared with patients with the greatest STS risk.

CONCLUSIONS

Patients with lower risk had a greater association between preoperative Hct and major morbidity and mortality compared with patients with greater risk. Preoperative anemia management is essential across all risk groups for improved outcomes.

Multiple Arterial Graft Use in Coronary Artery Bypass Surgery: Surgeon Perspective vs Practice

BACKGROUND

Despite supportive evidence and guidelines, the use of multiple arterial grafts (MAGs) in coronary artery bypass grafting remains low. We sought to determine surgeon perception of personal MAG use and compare this with actual MAG use.

METHODS

We conducted a statewide surgeon survey of MAG use, presence of a hospital MAG protocol, and barriers for MAG use, with a response rate of 78% (n = 25). Surgeon survey responses were compared with actual Society of Thoracic Surgeons patient data from January 1, 2017, to December 31, 2020 using χ2 or Fisher's exact tests.

RESULTS

Of 5299 patients who had first-time, nonemergent, isolated coronary artery bypass grafting (≥2 grafts) by responding surgeons, 16% received MAG (n = 825). MAG use in patients whose surgeons self-designated as "routine" MAG users was 21% vs 7% for "nonroutine" users. Surgeons with a hospital protocol for MAG use utilized MAG more often (18% vs 14%, P = .001). Surgeons who were unconvinced by the data on the benefits of MAGs used MAGs in 11% vs 22% in surgeons who were convinced. MAG use increased over time, particularly from before to after the survey (13.1% vs 30.5%, P < .001).

CONCLUSIONS

Although MAG use increased over time, barriers to routine use remain. In surgeons who reported routine use, only 21% of their patients received MAGs. Hospital protocols, education, and increased awareness may reduce barriers to use and encourage evidence-based clinical practice.

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.

Number and Type of Blood Products are Negatively Associated With Outcomes Following Cardiac Surgery

BACKGROUND

The association between blood transfusion and adverse outcome is documented in cardiac surgery. However, the incremental significance of each unit transfused, whether red blood cell (RBC) or non-RBC, is uncertain. This study examined the relationship of patient outcomes with type and number of blood product units transfused.

METHODS

Statewide data from adult cardiac surgery patients were included (N=24,082). Relationship with blood transfusion was assessed for morbidity and 30-day mortality using total number of RBC and non-RBC units transfused, specific type of non-RBC units, and different combinations of transfusion (only RBC, only non-RBC, RBC+non-RBC). Multivariable logistic regressions examined these associations.

RESULTS

Median age was 66 years (30% female) with 51% of patients transfused (31%-66% across hospitals). Risk-adjusted analyses found each blood product unit associated with 9%, 7%, and 4% greater odds for 30-day mortality, major morbidity, and minor morbidity (all P<0.001). Odds for 30-day mortality were 13% greater with each RBC unit (P<0.001) and 6% greater for each non-RBC unit (P<0.001). Each unit of fresh frozen plasma (P<0.001) and platelets (P<0.001) increased odds for 30-day mortality, but no effect for cryoprecipitate (P=0.725). Odds for 30-day mortality were lower for non-RBC only (OR=0.52, P=0.030) and greater for RBC+non-RBC (OR=2.98, P<0.001) compared to RBC only transfusion.

CONCLUSIONS

Independent of center variability on transfusion methods, each additional unit transfused was associated with increased odds for complications, with RBC transfusion carrying greater risk compared to non-RBC. Comprehensive evidence-based clinical approaches and coordination are needed to guide each blood transfusion event following cardiac surgery.

Clinical Practice Variation and Outcomes for Stanford Type A Aortic Dissection Repair Surgery in Maryland: Report from a Statewide Quality Initiative

Background  Stanford Type A aortic dissection repair surgery is associated with high mortality and clinical practice remains variable among hospitals. Few studies have examined statewide practice variation.

Methods  Patients who had Stanford Type A aortic dissection repair surgery in Maryland between July 1, 2014 and June 30, 2018 were identified using the Maryland Cardiac Surgery Quality Initiative (MCSQI) database. Patient demographics, comorbidities, surgery details, and outcomes were compared between hospitals. We also explored the impact of arterial cannulation site and brain protection technique on outcome.

Results  A total of 233 patients were included from eight hospitals during the study period. Seventy-six percent of surgeries were done in two high-volume hospitals (≥10 cases per year), while the remaining 24% were done in low-volume hospitals. Operative mortality was 12.0% and varied between 0 and 25.0% depending on the hospital. Variables that differed significantly between hospitals included patient age, the percentage of patients in shock, left ventricular ejection fraction, creatinine level, arterial cannulation site, brain protection technique, tobacco use, and intraoperative blood transfusion. The percentage of patients who underwent aortic valve repair or replacement procedures differed significantly between hospitals ( p  < 0.001), although the prevalence of moderate-to-severe aortic insufficiency was not significantly different ( p  = 0.14). There were no significant differences in clinical outcomes including mortality, renal failure, stroke, or gastrointestinal complications between hospitals or based on arterial cannulation site (all p  > 0.05). Patients who had aortic cross-clamping or endovascualr repair had more embolic strokes when compared with patients who had hypothermic circulatory arrest ( p  = 0.03).

Conclusion  There remains considerable practice variation in Stanford Type A aortic dissection repair surgery within Maryland including some modifiable factors such as intraoperative blood transfusion, arterial cannulation site, and brain protection technique. Continued efforts are needed within MCSQI and nationally to evaluate and employ the best practices for patients having acute aortic dissection repair surgery.

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.

Racial Disparity in Cardiac Surgery Risk and Outcome: Report From a Statewide Quality Initiative

BACKGROUND

Racial disparities persist in health care. Our study objective was to evaluate racial disparity in cardiac surgery in Maryland.

METHODS

A statewide database was used to identify patients. Demographics, comorbidities, and predicted risk of death were compared between races. Crude mortality and incidence of complications were compared between groups, as were risk-adjusted odds for mortality and major morbidity or mortality.

RESULTS

The study included 23,094 patients. Most patients were white (75.8%), followed by African American (16.3%), Asian (3.8%), and other races (4.1%). African Americans had a higher preoperative risk for mortality based on The Society of Thoracic Surgeons predictive models compared with white patients (3.0% vs 2.3%, P < .001). African Americans also had higher prevalence of diabetes mellitus, hypertension, peripheral vascular disease, and cerebral vascular disease than white patients. After adjustment for preoperative risk, there was no difference in 30-day mortality between African Americans (odds ratio [OR], 1.26; 95% confidence interval [CI], 0.99-1.59), Asians (OR, 1.22; 95% CI, 0.75-1.97), and other races (OR, 1.18; 95% CI, 0.74-1.89) compared with whites. African Americans had lower risk-adjusted odds of major morbidity or mortality compared with whites (OR, 0.83; 95% CI, 0.75-0.93).

CONCLUSIONS

African American cardiac surgical patients have the highest preoperative risk in Maryland. Patients appeared to receive excellent cardiac surgical care, regardless of race, as risk-adjusted mortality did not differ between groups, and African American patients had lower risk-adjusted odds of major morbidity or mortality than white patients. Future interventions in Maryland should be aimed at reducing preoperative risk disparity in cardiac surgical patients.

Abstract 31: Center-specific Variation in Use of Dual Antiplatelet Therapy Prior to Coronary Surgery: an Outcomes Analysis from the Maryland Cardiac Surgery Quality Initiative

Background: Understanding institutional practices and associated outcomes of patients managed with different dual antiplatelet therapy (DAPT) strategies prior to coronary artery bypass grafting (CABG) could inform practice improvement. We hypothesized that, while receipt of DAPT within 5 days prior to CABG would increase risk for postoperative bleeding, there is institutional variation in preoperative DAPT management.

Methods: A retrospective cohort study was performed using data from the Maryland Cardiac Surgery Quality Initiative (MCSQI), a consortium aggregating data from the 10 hospitals that perform cardiac surgery in Maryland. Isolated CABG patients between 2011 and 2018 were included. The exposure variable of interest was DAPT use within 5 days prior to CABG. The temporal trend in preoperative use of DAPT, heterogeneity in DAPT usage between centers, and perioperative outcomes are reported. The primary outcomes were the STS major morbidity/mortality composite measure and postoperative bleeding events.

Results: The sample included 13,965 patients, of which 23% ( n =3,219) received preoperative DAPT within 5 days of surgery. The percentage of CABG patients treated with DAPT within 5 days decreased over time from 26% in 2011 to 15% in 2018 (Figure, P <0.001 for trend). There was significant heterogeneity in preoperative DAPT use among centers within the state (Figure, P <0.001 for difference in proportions). CABG patients receiving preoperative DAPT were more likely to present with acute MI (49% v 27%, P <0.001) and less likely to present electively (19% v 34%, P <0.001). The ratio of observed-to-expected STS-defined morbidity/mortality was similar between DAPT (O/E 0.85, 95% CI 0.77-0.92) and non-DAPT groups (O/E 0.84, 95% CI 0.79-0.89). Median transfusion of blood products was higher for the DAPT group (1 [0-4] v 0 [0-3], P <0.001). In adjusted models, preoperative DAPT was associated with greater odds of reoperation for bleeding (OR=1.38, P =0.017) and transfusion of ≥2 PRBC units (OR=1.27, P <0.001).

Conclusion: Many isolated CABG patients in the state of Maryland are treated with DAPT within 5 days prior to CABG with notable variation between centers. Given the associated risk of postoperative bleeding, standardized management of preoperative DAPT therapy could improve post-CABG outcomes.

Variation in Platelet Transfusion Practices in Cardiac Surgery

Objective

Although the morbidity associated with red blood cell transfusion in cardiac surgery has been well described, the impacts of platelet transfusion are less clearly understood. Given the conflicting results of prior studies, we sought to investigate the impact of platelet transfusion on outcomes after cardiac surgery across institutions in Maryland.

Methods

Using a multiinstitutional statewide database created by the Maryland Cardiac Surgery Quality Initiative, we retrospectively analyzed data from 10,478 patients undergoing isolated coronary artery bypass across 10 centers. Platelet transfusion practices were compared between institutions. Multivariate logistic regression model was used to analyze the association between platelet transfusion and 30-day mortality and postoperative complications.

Results

Rates of platelet transfusion varied between institutions from 4.4% to 24.7% ( P < 0.001), a difference that remained statistically significant in propensity score–matched cohorts. Among patients on preoperative antiplatelet therapy, transfusion rates varied from 8.5% to 46.4% ( P < 0.001). There was no statistically significant relationship between case volume and transfusion rates ( P = 0.815). In multivariate logistic regression, platelet transfusion was associated with increased risk of 30-day mortality (OR 2.43, P = 0.008), postoperative pneumonia (OR 2.21, P = 0.004), prolonged intubation (OR 2.05, P < 0.001), and readmission (OR 1.43, P = 0.039).

Conclusions

Significant variation existed in platelet transfusion rates between institutions, even after controlling for various risk factors. This variation may be associated with increased mortality and length of stay. Further study is warranted to better understand risks associated with platelet transfusion. Standardizing practice may help reduce risk and conserve resources.

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.

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.

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.

Regional Practice Patterns and Outcomes of Surgery for Acute Type A Aortic Dissection

BACKGROUND

The surgical management of acute type A aortic dissection is evolving, and many aortic centers of excellence are reporting superior outcomes. We hypothesize that similar trends exist in a multiinstitutional regional consortium.

METHODS

Records for 884 consecutive patients who underwent aortic operations (2003 to 2015) for acute type A aortic dissection were extracted from a regional The Society of Thoracic Surgeons database. Patients were stratified into three equal operative eras. Differences in outcomes and risk factors for morbidity and mortality were determined.

RESULTS

Surgical procedures for type A aortic dissection are increasing in extent and complexity. Aortic root repair was performed in 16% of early era cases compared with 67% currently (p < 0.0001). Similarly, aortic arch repair increased from 27% to 37% cases (p < 0.0001). Cerebral perfusion is currently used in 85% of circulatory arrest cases, most frequently antegrade (57%). Total circulatory arrest times increased (29 minutes vs 31 minutes vs 36 minutes; p = 0.005), but times without cerebral perfusion were stable (12 minutes vs 6 minutes; p = 0.68). Although the operative mortality rate remained stable at 18.9% during the 3 operative eras, there were significant decreases in pneumonia and reoperations (p < 0.05). Predictors of operative mortality and major morbidity are age (odds ratio [OR], 1.04; p < 0.0001), previous stroke (OR, 2.09; p = 0.03), and elevated creatinine (OR, 1.31; p = 0.01). Importantly, the extent of aortic operation did not increase risk for morbidity or mortality.

CONCLUSIONS

Operative morbidity and mortality remain significant for type A aortic dissection, but lower than historical outcomes. The extent of aortic surgery has increased, resulting in adaptive cerebral protection changes in contemporary "real-world" practice.

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.

Impact of Medicaid Expansion on Cardiac Surgery Volume and Outcomes

BACKGROUND

Thirty-one states approved Medicaid expansion after implementation of the Affordable Care Act. The objective of this study was to evaluate the effect of Medicaid expansion on cardiac surgery volume and outcomes comparing one state that expanded to one that did not.

METHODS

Data from the Virginia (nonexpansion state) Cardiac Services Quality Initiative and the Michigan (expanded Medicaid, April 2014) Society of Thoracic and Cardiovascular Surgeons Quality Collaborative were analyzed to identify uninsured and Medicaid patients undergoing coronary bypass graft or valve operations, or both. Demographics, operative details, predicted risk scores, and morbidity and mortality rates, stratified by state and compared across era (preexpansion: 18 months before vs postexpansion: 18 months after), were analyzed.

RESULTS

In Virginia, there were no differences in volume between eras, whereas in Michigan, there was a significant increase in Medicaid volume (54.4% [558 of 1,026] vs 84.1% [954 of 1,135], p < 0.001) and a corresponding decrease in uninsured volume. In Virginia Medicaid patients, there were no differences in predicted risk of morbidity or mortality or postoperative major morbidities. In Michigan Medicaid patients, a significant decrease in predicted risk of morbidity or mortality (11.9% [8.1% to 20.0%] vs 11.1% [7.7% to 17.9%], p = 0.02) and morbidities (18.3% [102 of 558] vs 13.2% [126 of 954], p = 0.008) was identified. Postexpansion was associated with a decreased risk-adjusted rate of major morbidity (odds ratio, 0.69; 95% confidence interval, 0.51 to 0.91; p = 0.01) in Michigan Medicaid patients.

CONCLUSIONS

Medicaid expansion was associated with fewer uninsured cardiac surgery patients and improved predicted risk scores and morbidity rates. In addition to improving health care financing, Medicaid expansion may positively affect patient care and outcomes.

Obesity Increases Risk-Adjusted Morbidity, Mortality, and Cost Following Cardiac Surgery

BACKGROUND

Despite the epidemic rise in obesity, few studies have evaluated the effect of obesity on cost following cardiac surgery. We hypothesized that increasing body mass index (BMI) is associated with worse risk-adjusted outcomes and higher cost.

METHODS AND RESULTS

Medical records for 13 637 consecutive patients who underwent coronary artery bypass grafting (9702), aortic (1535) or mitral (837) valve surgery, and combined valve-coronary artery bypass grafting (1663) procedures were extracted from a regional Society of Thoracic Surgeons certified database. Patients were stratified by BMI: normal to overweight (BMI 18.5-30), obese (BMI 30-40), and morbidly obese (BMI >40). Differences in outcomes and cost were compared between BMI strata and also modeled as a continuous function of BMI with adjustment for preoperative risk using Society of Thoracic Surgeons predictive risk indices. Morbidly obese patients incurred nearly 60% greater observed mortality than normal weight patients. Moreover, morbidly obese patients had greater than 2-fold increase in renal failure and 6.5-fold increase in deep sternal wound infection. After risk adjustment, a significant association was found between BMI and mortality (P<0.001) and major morbidity (P<0.001). The risk-adjusted odds ratio for mortality for morbidly obese patients was 1.57 (P=0.02) compared to normal patients. Importantly, risk-adjusted total hospital cost increased with BMI, with 17.2% higher costs in morbidly obese patients.

CONCLUSIONS

Higher BMI is associated with increased mortality, major morbidity, and cost for hospital care. As such, BMI should be more strongly considered in risk assessment and resource allocation.

Minimally Invasive Mitral Valve Surgery Provides Excellent Outcomes Without Increased Cost: A Multi-Institutional Analysis

BACKGROUND

Minimally invasive mitral valve surgery (mini-MVR) has grown in popularity. Although single centers have reported excellent outcomes, data on real-world outcomes and costs of mini-MVR are limited. Moreover, mini-MVR has been criticized as adding additional cost without clear benefit. We hypothesized that mini-MVR provides superior outcomes with incremental increased costs in a multi-institutional cohort.

METHODS

Records for patients undergoing mitral valve surgical procedures with or without atrial ablation from 2011 to 2014 were extracted from a multi-institutional, regional Society of Thoracic Surgeons database and stratified according to right chest approach/minimally invasive or conventional sternotomy. Patients undergoing coronary artery bypass grafting or other concomitant procedures were excluded. Patients undergoing isolated mitral surgical procedure were propensity matched according to factors, including age, comorbidities, and preoperative laboratory values; clinical outcomes and cost differences were assessed by approach.

RESULTS

A total of 1,304 patients underwent mitral operations, including 425 (32.6%) by minimally invasive approach. In the propensity-matched analysis (n = 355 per group), patients undergoing mini-MVR had similar rates of mortality, stroke, and other complications compared with conventional MVR. Meanwhile, patients with mini-MVR experienced shorter intensive care unit and hospital lengths of stay and fewer transfusions. Importantly, total hospital costs were no different between the two matched groups.

CONCLUSIONS

Compared with conventional sternotomy, mini-MVR in the "real world" demonstrated no differences in rates of major morbidity, but it was associated with shorter length of stay and fewer transfusions. Contrary to our hypothesis, mini-MVR can be performed with similar total hospital costs as conventional sternotomy. In summary, minimally invasive mitral surgical procedure in select patients can provide superior outcomes without increased cost.

Costs for surgical aortic valve replacement according to preoperative risk categories

BACKGROUND

The introduction of transcatheter aortic valve replacement (TAVR) led to more rigorous evaluation of surgical aortic valve replacement (SAVR) as a benchmark for TAVR. However, limited real-life cost data of SAVR are available. Therefore, the purpose of our study was to assess actual costs and resource utilization of SAVR in patients at different operating risk.

METHODS

Study data were drawn from a multi-institutional statewide database comprised of all cardiac surgical procedures in the Commonwealth of Virginia. The study included 2,530 elective, primary, isolated SAVRs performed from 2003 to 2012. Clinical data were matched with universal billing data. Patients were stratified into low-, intermediate- and high-risk categories according to the Society of Thoracic Surgeons- Predicted Risk of Mortality (STS-PROM) score: 0% to 4%, 4% to 8% , and greater than 8%, respectively. Clinical outcomes, resource use, and costs were compared between categories.

RESULTS

With increasing risk, there were higher rates of postoperative mortality (low 1.2% versus intermediate 2.7% versus high 6.2%, p < 0.001) and renal failure (2.7% vs 7.2% vs 10.6%; p < 0.001). The proportion of patients with any postoperative complication was higher with increasing risk (34% vs 48% vs 53%; p < 0.001). Length-of-stay increased from 6.8 days in the low-risk category to 10.2 and 11.3 days in the intermediate- and high-risk category, respectively (p < 0.001). There was an increase in mean total costs from the low- (n = 2,002) to intermediate- (n = 415) to high-risk (n = 113) category ($35,021 ± $22,642 vs $46,101 ± $42,460 vs $51,145 ± $31,655; p < 0.001).

CONCLUSIONS

Higher STS-PROM was significantly associated with higher postoperative mortality, complications, length-of-stay, and costs. The SAVR cost data provide a basis for the analysis of TAVR cost-effectiveness and its impact on payment systems.