Determinants of variations in coronary revascularization practices

Outcomes Following Percutaneous Coronary Intervention in Patients With Multivessel Disease Who Were Recommended for But Declined Coronary Artery Bypass Graft Surgery

BACKGROUND

Patients may prefer percutaneous coronary intervention (PCI) over coronary artery bypass graft (CABG) surgery, despite heart team recommendations. The outcomes in such patients have not been examined. We sought to examine the results of PCI in patients who were recommended for but declined CABG.

METHODS AND RESULTS

Consecutive patients with stable ischemic heart disease and unprotected left main or 3-vessel disease or Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery score >22 who underwent PCI after heart team review between 2013 and 2020 were included. Patients were categorized into 3 groups according to heart team recommendations on the basis of appropriate use criteria: (1) PCI-recommended; (2) CABG-eligible but refused CABG (CABG-refusal); and (3) CABG-ineligible. The primary end point was the composite of death, myocardial infarction, or stroke at 1 year. The study included 3687 patients undergoing PCI (PCI-recommended, n=1718 [46.6%]), CABG-refusal (n=1595 [43.3%]), and CABG-ineligible (n=374 [10.1%]). Clinical and procedural risk increased across the 3 groups, with the highest comorbidity burden in CABG-ineligible patients. Composite events within 1 year after PCI occurred in 55 (4.1%), 91 (7.0%), and 41 (14.8%) of patients in the PCI-recommended, CABG-refusal, and CABG-ineligible groups, respectively. After multivariable adjustment, the risk of the primary composite outcome was significantly higher in the CABG-refusal (hazard ratio [HR], 1.67 [95% CI, 1.08-3.56]; P=0.02) and CABG-ineligible patients (HR, 3.26 [95% CI, 1.28-3.65]; P=0.004) groups compared with the reference PCI-recommended group, driven by increased death and stroke.

CONCLUSIONS

Cardiovascular event rates after PCI were significantly higher in patients with multivessel disease who declined or were ineligible for CABG. Our findings provide real-world data to inform shared decision-making discussions.

Cardiovascular surgery and cardiology, current status of two sister specialties in Spain: the CARDIOXCARDIO study

In recent years, there has been a notable shift in cardiovascular clinical practice within cardiology and surgery. The CARDIOXCARDIO study aimed to identify professionals' opinions on working practices and relations between specialties. A survey was simultaneously sent to the 4442 members of the Spanish Society of Cardiovascular and Endovascular Surgery (SECCE) and the Spanish Society of Cardiology (SEC), yielding 385 valid responses. More than half (59%) of respondents were men, mostly specialists (7.3% residents), and 74.8% worked in the field of cardiology, predominantly in public centers (88.3%). Using a Likert scale ranging from 1 to 5 (worst to best), respondents rated relations between surgery and cardiology with an average of 3.57±0.9 points. Cardiologists rated surgeons with a mean score of 3.83±0.8, while surgeons gave cardiologists a mean score of 3,92±0.72. In addition, respondents provided numerous suggestions for improvement, which are discussed in detail, highlighting certain discrepancies in criteria between specialties. Implementing strategies based on the suggestions of professionals, together with a proactive approach to continuous improvement, could substantially enhance the quality of cardiovascular care in Spain.

Appropriateness of Surgical Aortic Valve Replacement for Severe Aortic Stenosis Is Increasing

BACKGROUND

The adoption of transcatheter aortic valve replacement led to the development of appropriate use criteria (AUC) for transcatheter and surgical aortic valve replacement (SAVR) for aortic stenosis in 2017. This study hypothesized that appropriateness of SAVR improved after publication of AUC.

METHODS

All patients undergoing isolated SAVR for severe aortic stenosis in a regional cardiac surgical quality collaborative were evaluated using data from the Society of Thoracic Surgeons Adult Cardiac Surgery Database (2011-2021). After excluding endocarditis and emergency cases, appropriateness of SAVR (rarely appropriate, may be appropriate, or appropriate) was assigned to patients by using established criteria. The relationship of appropriateness with publication of AUC was assessed, as was variation in appropriateness over time and by center.

RESULTS

Of 3035 patients across 17 centers, 106 (3.5%) underwent SAVR for an indication identified as rarely appropriate or may be appropriate. Patients who underwent SAVR for rarely or may be appropriate indications were significantly more likely to experience operative mortality (5.7% vs 1.6%, P = .001) as well as major morbidity (21.7% vs 10.5%, P < .001). Performance of rarely or may be appropriate SAVR significantly decreased over time (slope -0.51%/year, P trend < .001), and it was decreased after the release of the AUC (before release, 3.83% vs after release, 2.06%; P = .036). Substantial interhospital variation in appropriateness was observed (range of may be or rarely appropriate SAVR, 0%-10%).

CONCLUSIONS

The majority of isolated SAVR for aortic stenosis was appropriate according to the 2017 AUC. Appropriateness improved after publication of AUC, and this improvement was associated with a significant reduction of major morbidity and mortality.

Derivation and validation of predictive indices for cardiac readmission after coronary and valvular surgery - A multicenter study

Objective

To derive and validate models to predict the risk of a cardiac readmission within one year after specific cardiac surgeries using information that is commonly available from hospital electronic medical records.

Methods

In this retrospective cohort study, we derived and externally validated clinical models to predict the likelihood of cardiac readmissions within one-year of isolated CABG, AVR, and combined CABG+AVR in Ontario, Canada, using multiple clinical registries and routinely collected administrative databases. For all adult patients who underwent these procedures, multiple Fine and Gray subdistribution hazard models were derived within a competing-risk framework using the cohort from April 2015 to March 2018 and validated in an independent cohort (April 2018 to March 2020).

Results

For the model that predicted post-CABG cardiac readmission, the c-statistic was 0.73 in the derivation cohort and 0.70 in the validation cohort at one-year. For the model that predicted post-AVR cardiac readmission, the c-statistic was 0.74 in the derivation and 0.73 in the validation cohort at one-year. For the model that predicted cardiac readmission following CABG+AVR, the c-statistic was 0.70 in the derivation and 0.66 in the validation cohort at one-year.

Conclusions

Prediction of one-year cardiac readmission for isolated CABG, AVR, and combined CABG+AVR can be achieved parsimoniously using multidimensional data sources. Model discrimination was better than existing models derived from single and multicenter registries.

Severity of obstructive coronary artery stenosis after pre-eclampsia

INTRODUCTION

Women with a history of pre-eclampsia are at higher risk of premature coronary artery disease. Assessment of obstructive coronary artery stenosis by invasive coronary angiography has not been evaluated after pre-eclampsia.

METHODS

A population-based cohort study was completed in Ontario, Canada, where there is universal healthcare and collection of angiographic data. Included were women with a live birth or stillbirth from 2002 to 2020, and without known heart disease. One birth was randomly selected per woman. The main exposure compared women with versus without pre-eclampsia. The primary outcome was angiographically established obstructive coronary artery stenosis, assessed starting 42 days after the index birth. Cause-specific hazard models accounting for competing risks generated HRs, adjusted for age, parity, income, rurality, diabetes, chronic hypertension, renal disease, substance use and dyslipidaemia.

RESULTS

Among 42 252 women ever with pre-eclampsia and 1359 122 never with pre-eclampsia, mean age was 31.1 years and 30.6 years, respectively. After 9 years of follow-up, obstructive coronary artery stenosis occurred in 186 women with pre-eclampsia (4.53 per 10 000 person-years) versus 1237 women without pre-eclampsia (0.97 per 10 000 person-years)-an unadjusted HR 4.41 (95% CI 3.78 to 5.14) and adjusted HR 2.07 (95% CI 1.77 to 2.43). Relative to those with neither, the adjusted HR for coronary stenosis was highest in women with pre-eclampsia and preterm birth (3.11, 95% CI 2.51 to 3.87), or pre-eclampsia and stillbirth (2.80, 95% CI 1.05 to 7.47).

CONCLUSIONS

Pre-eclampsia is associated with a greater risk of premature-onset obstructive coronary artery stenosis, especially when it is complicated by a preterm birth or a stillbirth.

Association of Race and Ethnicity With Obstructive Coronary Artery Disease

Background

Appropriate selection of patients with stable coronary artery disease (CAD) for coronary angiography is dependent on the pretest probability of obstructive CAD; however, little is known about the potential differences in CAD by race and ethnic groups.

Objectives

The purpose of this study was to evaluate the association of race and ethnicity with coronary obstruction in stable CAD.

Methods

We evaluated first coronary angiography for CAD evaluation between 2012 and 2019 in Ontario, Canada. Race and ethnicity were identified by physicians. The main outcome was the rate of obstructive CAD (left main stenosis ≥50% or major epicardial vessel stenosis ≥70%). Multivariable logistic regression analyses evaluated the independent association of race and ethnicity with CAD.

Results

Among 71,199 CAD patients, 14.0% were South Asian (SA), 4.4% were East Asian (EA), and 58,131 were White patients. SA patients were the youngest at 60.9 years vs 62.4 years for EA patients and 65.1 years for White patients but were most likely to have obstructive CAD (46.9%) (EA 43.0% and White patients 37.9%). SA patients had the highest prevalence of 3-vessel CAD at 13.4% (vs 12.5% in EA and 7.7% in White patients). The adjusted odds ratio was 67% higher (1.67; 95% CI: 1.59 to 1.75) for having obstructive CAD in SA patients than that in White patients. EA patients also had significantly increased adjusted odds of obstructive CAD compared with White patients (1.40; 95% CI: 1.29-1.52).

Conclusions

SA patients were younger at presentation but had the highest adjusted odds of obstructive CAD. Incorporation of race and ethnicity information may improve risk-prediction tools for detection of coronary obstruction.

Patient, physician and geographic predictors of cardiac stress testing strategy in Ontario, Canada: a population-based study

OBJECTIVES

To identify patient, physician and geographic level factors that are associated with variation in initial stress testing strategy in patients evaluated for chest pain.

DESIGN

Retrospective cohort study.

SETTING

Population-based study of patients undergoing evaluation for chest pain in Ontario, Canada between 1 January 2011 and 31 March 2018.

PARTICIPANTS

103 368 patients who underwent stress testing (graded exercise stress testing (GXT), stress echocardiography (stress echo) or myocardial perfusion imaging (MPI)) following evaluation for chest pain.

PRIMARY AND SECONDARY OUTCOME MEASURES

To identify the patient, physician and geographic level factors associated with variation in initial test selection, we fit two separate 2-level hierarchical multinomial logistic regression models for which the outcome was initial stress testing strategy (GXT, MPI or stress echo).

RESULTS

There was significant variability in the initial type of stress test performed, with approximately 50% receiving a GXT compared with approximately 36% who received MPI and 14% who received a stress echo. Physician-level factors were key drivers of this variation, accounting for up to 59.0% of the variation in initial testing. Physicians who graduated medical school >30 years ago were approximately 45% more likely to order an initial stress echo (OR 1.45, 95% CI 1.17 to 1.80) than a GXT. Cardiovascular disease specialists were approximately sevenfold more likely to order an initial MPI (OR 7.35, 95% CI 5.38 to 10.03) than a GXT. Patients aged >70 years were approximately fivefold more likely to receive an MPI (OR 4.74, 95% CI 4.42 to 5.08) and approximately 26% more likely to receive a stress echo (OR 1.26, 95% CI 1.15 to 1.38) than a GXT.

CONCLUSIONS

We report significant variability in initial stress testing strategy in Ontario. Much of that variability was driven by physician-level factors that could potentially be addressed through educational campaigns geared at reducing this variability and improving guideline adherence.

Single Versus Multiple Arterial Revascularization in Patients With Reduced Renal Function: Long-term Outcome Comparisons in 23,406 CABG Patients From Ontario, Canada

OBJECTIVE

To compare the long-term outcomes of MAR versus SAR in patients with renal insufficiency.

SUMMARY OF BACKGROUND DATA

Previous studies have been insufficiently powered to address whether MAR confers long-term benefit over SAR in patients with renal dysfunction who require CABG.

METHODS

We conducted retrospective cohort study in Ontario, Canada of patients who underwent isolated CABG (n = 23,406). The primary outcome was MACE, defined as the composite of stroke, myocardial infarction, and repeat revascularization. We compared patients by matching them on the propensity to have received SAR versus MAR, within groups with preoperative glomerular filtration rate (GFR) ≥60 mL/min/1.73 m2; GFR between 30 and 60; and GFR <30.

RESULTS

In patients with GFR ≥60, the use of MAR versus SAR was associated with a lower rate of MACE [hazard ratio (HR) 0.87 (0.80-0.94)], and a lower rate of long-term mortality [HR 0.87 (0.79-0.97)]. In those with GFR between 30 and 60, MAR was not associated with a difference in MACE [HR 1.04 (0.87-1.26)], and a lower rate of long-term mortality [HR 0.75 (0.65-0.87)] was observed. In those with GFR <30, MAR was not associated with a difference in outcomes.

CONCLUSIONS

MAR versus SAR does not correlate with a difference in MACE amongst patients with GFR between 30 and 60 and better survival raises the possibility of indication bias. Furthermore, MAR did not confer a benefit in those with severely reduced renal function. These data suggest that the potential long-term benefits of using MAR in CABG patients with renal insufficiency may be offset by competing health risks.

Rates of revascularization and PCI:CABG ratio: a new indicator predicting in-hospital mortality in acute coronary syndromes

OBJECTIVE

The principal trend in acute coronary syndrome (ACS) is increasing utilization of percutaneous coronary interventions (PCI) and declining coronary artery bypass graft surgery (CABG) utilization. This study was designed to evaluate whether higher PCI:CABG ratios lead to higher in-hospital PCI or CABG mortality.

METHODS

The National Readmission Database for years 2016 was queried for all hospitalized ACS patients who underwent coronary revascularization during their admission. The study population was derived from 355 US hospitals and included 103 021 patients. Hospitals were grouped based on their PCI:CABG ratio into low, intermediate, and high ratio quartiles with a median [interquartile ranges (IQR)] PCI:CABG ratio of 2.9 (2.5-3.2), 5.0 (4.3-5.9) and 8.9 (7.8-10.3), respectively multivariable logistic regression with adjustment for age, demographics and comorbidities were used to identify CABG:PCI ratio related risk for in-hospital CABG and PCI mortality.

RESULTS

Higher PCI:CABG ratios correlated with an increased CABG mortality. There was a median (IQR) mortality of 2.5% (1.6-4.3) in the low ratio quartile; 3.1% (1.9-5.3) in the intermediate quartiles; and 5.3% (3.2-9.1) in the high ratio quartile (P < 0.001). On multivariate analysis, the PCI:CABG ratio was associated with an increased risk for CABG mortality with an adjusted odds ratio of 1.38 (95% CI, 1.14-1.67, P < 0.001) and 2.17 (95% CI, 1.70-2.80, P < 0.001) for hospitals with intermediate and high PCI:CABG ratios, respectively. There was no significant association between PCI:CABG ratio and PCI mortality.

CONCLUSIONS

The programmatic PCI:CABG ratio is a valid indicator of optimal case selection. The PCI:CABG ratio correlates with in-hospital mortality in ACS.

Variations in Coronary Revascularization Practices and Their Effect on Long-Term Outcomes

Background

The degree of hospital‐level variation in the ratio of percutaneous coronary interventions to coronary artery bypass grafting procedures (PCI:CABG) and the association of the PCI:CABG ratio with clinical outcome are unknown.

Methods and Results

In a multicenter population‐based study conducted in Ontario, Canada, we identified 44 288 patients from 19 institutions who had nonemergent diagnostic angiograms indicating severe multivessel coronary artery disease (2013–2017) and underwent a coronary revascularization procedure within 90 days. Hospitals were divided into tertiles according to their adjusted PCI:CABG ratio into low (0.70–0.85, n=17 487), medium (1.01–1.17, n=15 275), and high (1.18–1.29, n=11 526) ratio institutions. Compared with low PCI:CABG ratio hospitals, hazard ratios (HRs) for major adverse cardiac and cerebrovascular events were higher at medium (HR, 1.19; 95% CI, 1.14–1.25) and high ratio (HR, 1.21; 95% CI, 1.15–1.27) hospitals during a median 3.3 (interquartile range 2.1–4.6) years follow‐up. When interventional cardiologists performed the diagnostic angiogram, the odds of the patient receiving PCI was higher (odds ratio, 1.37; 95% CI, 1.23–1.52) than when it was performed by noninterventional cardiologists, after accounting for patient characteristics. Having the diagnostic angiogram at an institution without cardiac surgical capabilities was independently associated with a higher risk of major adverse cardiac and cerebrovascular events (HR, 1.07; 95% CI, 1.02–1.11), death (HR, 1.09; 95% CI, 1.02–1.18), and myocardial infarction (HR, 1.10; 95% CI, 1.03–1.17).

Conclusions

Patients undergoing diagnostic angiography in hospitals with higher PCI:CABG ratio had higher rates of adverse outcomes, including major adverse cardiac and cerebrovascular events, myocardial infarction, and repeat revascularization. Presence of on‐site cardiac surgery was associated with better survival and lower major adverse cardiac and cerebrovascular events.

Modifiable Risk Factors and Residual Risk Following Coronary Revascularization: Insights From a Regionalized Dedicated Follow-Up Clinic

OBJECTIVE

To ensure compliance with optimal secondary prevention strategies and document the residual risk of patients following revascularization, we established a postrevascularization clinic for risk-factor optimization at 1 year, with outcomes recorded in a web-based registry. Although coronary revascularization can reduce ischemia, medical treatment of coronary artery disease (CAD) remains the cornerstone of ongoing risk reduction. While standardized referral pathways and protocols for revascularization are prevalent and well studied, post-revascularization care is often less formalized.

PATIENTS AND METHODS

The University of Ottawa Heart Institute is a tertiary-care center providing coronary revascularization services. From 2015 to 2019, data were prospectively recorded in the CAPITAL revascularization registry, and patient-level procedural, clinical, and outcome data are collected in the year following revascularization. Major adverse cardiovascular event (MACE) was defined as death, myocardial infarction, unplanned revascularization, or cerebrovascular accident. Kaplan-Meier curves were generated to evaluate time-to-event data for clinical outcomes by risk-factor management, and comparisons were performed using log-rank tests and reported by hazard ratio (HR) and 95% confidence intervals (CIs).

RESULTS

A cohort of 4147 patients completed 1-year follow-up after revascularization procedure that included 3462 undergoing percutaneous coronary intervention (PCI), 589 undergoing coronary artery bypass graft (CABG), and 96 undergoing both PCI and CABG. In the year following revascularization (median follow-up 13.3 months-interquartile range [IQR]: 11.9-16.5) 11% of patients experienced MACE, with female patients being disproportionately at risk. Moreover, 47.7% of patients had ≥2 risk factors (diabetes, dyslipidemia, overweight, active smoker) at the time of follow-up, with 45.0% of patients with diabetes failing to achieve target hemoglobin (Hb) A1c, 54.8% of smokers continuing to smoke, and 27.1% of patients failing to achieve guideline-directed lipid targets.

CONCLUSION

Patients who have undergone revascularization procedures remain at elevated risk for MACE, and inadequately controlled risk factors are prevalent in follow-up. This highlights the need for aggressive secondary prevention strategies and implementation of programs to optimize postrevascularization care.

Association Between Sarcopenia and Adverse Events Following Transcatheter Aortic Valve Implantation

Background

Sarcopenia, the age-related loss of skeletal muscle mass/function, has been identified as a marker of frailty. We examined the association between sarcopenia and adverse events following transcatheter aortic valve implantation (TAVI).

Methods

A retrospective cohort study was conducted at Toronto General Hospital. All patients who underwent TAVI in the time period 2007-2017 with preoperative computed tomography were included. Skeletal muscle index (SMI) was calculated radiographically using psoas muscle area at the L3 vertebral level, divided by height. Various measures of sarcopenia, including mean SMI, SMI below the sex-specific median, and SMI in the lowest sex-specific quartile were calculated. The primary outcome was postoperative adverse events, defined as a composite of in-hospital mortality and morbidity including cardiovascular, pulmonary, neurologic, access-related, and gastrointestinal complications. Univariate and multivariate logistic regression were performed to determine the association between sarcopenia and adverse events.

Results

A total of 468 patients (mean age: 80.7 years) were included. Baseline comorbidity burden was high, particularly congestive heart failure (93.4%). Postoperative adverse events occurred in 62 patients (13.2%). Univariate logistic regression demonstrated that postoperative adverse events were correlated with mean SMI (odds ratio [OR] 0.81, 95% confidence interal [CI] 0.66-0.97), events were less than the SMI (OR 2.16, 95% CI 1.24-3.84), and SMI in the sex-specific lowest quartile (OR 2.34, 95% CI 1.33-4.07). On multivariate analysis, SMI in the sex-specific lowest quartile was an independent predictor of adverse events (OR 2.53, 95% CI 1.41-4.50).

Conclusions

Sarcopenia defined by radiologic psoas muscle measurements was independently associated with in-hospital mortality and morbidity following TAVI.

Cardiology providers' recommendations for treatments and use of patient decision aids for multivessel coronary artery disease

Background

Rates of recommending percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) vary across clinicians. Whether clinicians agree on preferred treatment options for multivessel coronary artery disease patients has not been well studied.

Methods and results

We distributed a survey to 104 clinicians from the Northern New England Cardiovascular Study Group through email and at a regional meeting with 88 (84.6%) responses. The survey described three clinical vignettes of multivessel coronary artery disease patients. For each patient vignette participants selected appropriate treatment options and whether they would use a patient decision aid. The likelihood of choosing PCI only or PCI/CABG over CABG only was modeled using a multinomial regression. Across all vignettes, participants selected CABG only as an appropriate treatment option 24.2% of the time, PCI only 25.4% of the time, and both CABG or PCI as appropriate treatment options 50.4% of the time. Surgeons were less likely to choose PCI over CABG (RR 0.14, 95% CI 0.03, 0.59) or both treatments over CABG only (RR 0.10, 95% CI 0.03, 0.34) relative to cardiologists. Overall, 65% of participants responded they would use a patient decision aid with each vignette.

Conclusions

There is a lack of consensus on the appropriate treatment options across cardiologists and surgeons for patients with multivessel coronary artery disease. Treatment choice is influenced by both patient characteristics and clinician specialty.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02223-y.

Impact of surgeon and anaesthesiologist sex on patient outcomes after cardiac surgery: a population-based study

BACKGROUND

Effective teamwork between anaesthesiologists and surgeons is essential for optimising patient safety in the cardiac operating room. While many factors may influence the relationship between these two physicians, the role of sex and gender have yet to be investigated.

OBJECTIVES

We sought to determine the association between cardiac physician team sex discordance and patient outcomes.

DESIGN

We performed a population-based, retrospective cohort study.

PARTICIPANTS AND SETTING

Adult patients who underwent coronary artery bypass grafting (CABG) and/or aortic, mitral or tricuspid valve surgery between 2008 and 2018 in Ontario, Canada.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was all-cause 30-day mortality. Secondary outcomes included major adverse cardiovascular events at 30 days and hospital and intensive care unit lengths of stay (LOS). Mixed effects logistic regression was used for categorical outcomes and Poisson regression for continuous outcomes.

RESULTS

79 862 patients underwent cardiac surgery by 98 surgeons (11.2% female) and 279 anaesthesiologists (23.3% female); 19 893 (24.9%) were treated by sex-discordant physician teams. Physician sex discordance was not associated with overall patient mortality or LOS; however, patients who underwent isolated CABG experienced longer hospital LOS when treated by an all-male physician team as compared with an all-female team (adjusted OR=1.07; p=0.049). When examining the impact of individual physician sex, the length of hospital stay was longer when isolated CABG procedures were attended by a male surgeon (OR=1.10; p=0.004) or anaesthesiologist (OR=1.02; p=0.01).

CONCLUSIONS

Patient mortality and length of stay after cardiac surgery may vary by sex concordance of the attending surgeon-anaesthesiologist team. Further research is needed to examine the underlying mechanisms of these observed relationships.

Disability-free survival after major cardiac surgery: a population-based retrospective cohort study

BACKGROUND

Cardiovascular research has traditionally been dedicated to "tombstone" outcomes, with little attention dedicated to the patient's perspective. We evaluated disability-free survival as a patient-defined outcome after cardiac surgery.

METHODS

We conducted a retrospective cohort study of patients aged 40 years and older who underwent coronary artery bypass grafting (CABG) or single or multiple valve (aortic, mitral, tricuspid) surgery in Ontario between Oct. 1, 2008, and Dec. 31, 2016. The primary outcome was disability (a composite of stroke, 3 or more nonelective hospital admissions and admission to a long-term care facility) within 1 year after surgery. We assessed the procedure-specific risk of disability using cumulative incidence functions, and the relative effect of covariates on the subdistribution hazard using Fine and Gray models.

RESULTS

The study included 72 824 patients. The 1-year incidence of disability and death was 2431 (4.6%) and 1839 (3.5%) for CABG, 677 (6.5%) and 539 (5.2%) for single valve, 118 (9.0%) and 140 (10.7%) for multiple valve, 718 (9.0%) and 730 (9.2%) for CABG and single valve, and 87 (13.1%) and 94 (14.1%) for CABG and multiple valve surgery, respectively. With CABG as the reference group, the adjusted hazard ratios for disability were 1.34 (95% confidence interval [CI] 1.21-1.48) after single valve, 1.43 (95% CI 1.18-1.75) after multiple valve, 1.38 (95% CI 1.26-1.51) after CABG and single valve, and 1.78 (95% CI 1.43-2.23) after CABG and multiple valve surgery. Combined CABG and multiple valve surgery, heart failure, creatinine 180 μmol/L or greater, alcohol use disorder, dementia and depression were independent risk factors for disability.

INTERPRETATION

The cumulative incidence of disability was lowest after CABG and highest after combined CABG and multiple valve surgery. Our findings point to a need for models that predict personalized disability risk to enable better patient-centred care.

Determinants of the Downward Trend in Coronary Artery Bypass Graft Surgery Among Patients With Multivessel Disease and Class-I Indication for Surgery

Introduction

Coronary artery bypass graft (CABG) is the most effective coronary revascularization procedure, and it has been endorsed by many trials and studies over the years. However, due to CABG's immediate adverse effects, patients tend to prefer percutaneous coronary intervention (PCI) for coronary revascularization over it. This article focuses on the recent downtrend in CABG procedures for revascularization among patients for whom it is indicated. This study’s main objective was to identify the factors responsible for the downtrend in patients undergoing CABG despite a clear indication for it in those with multivessel diseases.

Methods

This study was conducted at the Lady Reading Hospital, Peshawar, Pakistan, from August 1, 2020, to January 1, 2021. A total of 340 patients with a class-I indication (presence of conditions regarding which there is evidence and/or general agreement that a given procedure or treatment is beneficial, useful, and effective) for CABG were enrolled in the study. Data related to all the variables were collected from patients and hospital records through an adequately designed proforma. For analysis, we applied the chi-square test to elaborate on the data for information and point biserial correlation to rule out the effect of age and weight on CABG’s downward trend.

Results

The mean age of the patients was 58.77 ± 9.54 years; 65.88% were male, and 34.12% were female. Only 17.65% of the patients underwent CABG; 71.47% opted for medical treatment, and 9.41% underwent PCI. Out of the 280 patients who did not undergo CABG, 26.76% had financial issues; 23.82% were high-risk patients and hence refused surgeries by the surgeons; 20.59% of patients were not willing to undergo surgery; 7.94% were on the waiting list, and 3.24% had deranged renal function tests (RFTs).

Conclusions

A limited number of patients underwent revascularization therapy even though they had clear indications for CABG. The high-risk status of patients, patients' unwillingness, and the cost of the procedure were the primary reasons behind the downtrend in CABG procedures among patients with a clear indication for the same.

Long-term Outcomes in Patients With Severely Reduced Left Ventricular Ejection Fraction Undergoing Percutaneous Coronary Intervention vs Coronary Artery Bypass Grafting

Importance

Data are lacking on the outcomes of patients with severely reduced left ventricular ejection fraction (LVEF) who undergo revascularization by percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG).

Objective

To compare the long-term outcomes in patients undergoing revascularization by PCI or CABG.

Design, Setting, and Participants

This retrospective cohort study performed in Ontario, Canada, from October 1, 2008, and December 31, 2016, included data from Ontario residents between 40 and 84 years of age with LVEFs less than 35% and left anterior descending (LAD), left main, or multivessel coronary artery disease (with or without LAD involvement) who underwent PCI or CABG. Exclusion criteria were concomitant procedures, previous CABG, metastatic cancer, dialysis, CABG and PCI on the same day, and emergency revascularization within 24 hours of a myocardial infarction (MI). Data analysis was performed from June 2, 2018, to December 28, 2018.

Exposures

Revascularization by PCI or CABG.

Main Outcomes and Measures

The primary outcome was all-cause mortality. Secondary outcomes were death from cardiovascular disease, major adverse cardiovascular events (MACE; defined as stroke, subsequent revascularization, and hospitalization for MI or heart failure), and each of the individual MACE.

Results

A total of 12 113 patients (mean [SD] age, 64.8 (11.0) years for the PCI group and 65.6 [9.7] years for the CABG group; 5084 (72.5%) male for the PCI group and 4229 (82.9%) male for the PCI group) were propensity score matched on 30 baseline characteristics: 2397 patients undergoing PCI and 2397 patients undergoing CABG. The median follow-up was 5.2 years (interquartile range, 5.0-5.3). Patients who received PCI had significantly higher rates of mortality (hazard ratio [HR], 1.6; 95% CI, 1.3-1.7), death from cardiovascular disease (HR 1.4, 95% CI, 1.1-1.6), MACE (HR, 2.0; 95% CI, 1.9-2.2), subsequent revascularization (HR, 3.7; 95% CI, 3.2-4.3), and hospitalization for MI (HR, 3.2; 95% CI, 2.6-3.8) and heart failure (HR, 1.5; 95% CI, 1.3-1.6) compared with matched patients who underwent CABG.

Conclusions and Relevance

In this study, higher rates of mortality and MACE were seen in patients who received PCI compared with those who underwent CABG. The findings may provide insight to physicians who are involved in decision-making for these patients.

Derivation and Validation of a Clinical Model to Predict Intensive Care Unit Length of Stay After Cardiac Surgery

Background Across the globe, elective surgeries have been postponed to limit infectious exposure and preserve hospital capacity for coronavirus disease 2019 (COVID-19). However, the ramp down in cardiac surgery volumes may result in unintended harm to patients who are at high risk of mortality if their conditions are left untreated. To help optimize triage decisions, we derived and ambispectively validated a clinical score to predict intensive care unit length of stay after cardiac surgery. Methods and Results Following ethics approval, we derived and performed multicenter valida tion of clinical models to predict the likelihood of short (≤2 days) and prolonged intensive care unit length of stay (≥7 days) in patients aged ≥18 years, who underwent coronary artery bypass grafting and/or aortic, mitral, and tricuspid value surgery in Ontario, Canada. Multivariable logistic regression with backward variable selection was used, along with clinical judgment, in the modeling process. For the model that predicted short intensive care unit stay, the c-statistic was 0.78 in the derivation cohort and 0.71 in the validation cohort. For the model that predicted prolonged stay, c-statistic was 0.85 in the derivation and 0.78 in the validation cohort. The models, together termed the CardiOttawa LOS Score, demonstrated a high degree of accuracy during prospective testing. Conclusions Clinical judgment alone has been shown to be inaccurate in predicting postoperative intensive care unit length of stay. The CardiOttawa LOS Score performed well in prospective validation and will complement the clinician's gestalt in making more efficient resource allocation during the COVID-19 period and beyond.

Redevelopment and validation of the SYNTAX score II to individualise decision making between percutaneous and surgical revascularisation in patients with complex coronary artery disease: secondary analysis of the multicentre randomised controlled SYNTAXES trial with external cohort validation

BACKGROUND

Randomised controlled trials are considered the gold standard for testing the efficacy of novel therapeutic interventions, and typically report the average treatment effect as a summary result. As the result of treatment can vary between patients, basing treatment decisions for individual patients on the overall average treatment effect could be suboptimal. We aimed to develop an individualised decision making tool to select an optimal revascularisation strategy in patients with complex coronary artery disease.

METHODS

The SYNTAX Extended Survival (SYNTAXES) study is an investigator-driven extension follow-up of a multicentre, randomised controlled trial done in 85 hospitals across 18 North American and European countries between March, 2005, and April, 2007. Patients with de-novo three-vessel and left main coronary artery disease were randomly assigned (1:1) to either the percutaneous coronary intervention (PCI) group or coronary artery bypass grafting (CABG) group. The SYNTAXES study ascertained 10-year all-cause deaths. We used Cox regression to develop a clinical prognostic index for predicting death over a 10-year period, which was combined, in a second stage, with assigned treatment (PCI or CABG) and two prespecified effect-modifiers, which were selected on the basis of previous evidence: disease type (three-vessel disease or left main coronary artery disease) and anatomical SYNTAX score. We used similar techniques to develop a model to predict the 5-year risk of major adverse cardiovascular events (defined as a composite of all-cause death, non-fatal stroke, or non-fatal myocardial infarction) in patients receiving PCI or CABG. We then assessed the ability of these models to predict the risk of death or a major adverse cardiovascular event, and their differences (ie, the estimated benefit of CABG versus PCI by calculating the absolute risk difference between the two strategies) by cross-validation with the SYNTAX trial (n=1800 participants) and external validation in the pooled population (n=3380 participants) of the FREEDOM, BEST, and PRECOMBAT trials. The concordance (C)-index was used to measure discriminative ability, and calibration plots were used to assess the degree of agreement between predictions and observations.

FINDINGS

At cross-validation, the newly developed SYNTAX score II, termed SYNTAX score II 2020, showed a helpful discriminative ability in both treatment groups for predicting 10-year all-cause deaths (C-index=0·73 [95% CI 0·69-0·76] for PCI and 0·73 [0·69-0·76] for CABG) and 5-year major adverse cardiovascular events (C-index=0·65 [0·61-0·69] for PCI and C-index=0·71 [0·67-0·75] for CABG). At external validation, the SYNTAX score II 2020 showed helpful discrimination (C-index=0·67 [0·63-0·70] for PCI and C-index=0·62 [0·58-0·66] for CABG) and good calibration for predicting 5-year major adverse cardiovascular events. The estimated treatment benefit of CABG over PCI varied substantially among patients in the trial population, and the benefit predictions were well calibrated.

INTERPRETATION

The SYNTAX score II 2020 for predicting 10-year deaths and 5-year major adverse cardiovascular events can help to identify individuals who will benefit from either CABG or PCI, thereby supporting heart teams, patients, and their families to select optimal revascularisation strategies.

FUNDING

The German Heart Research Foundation and the Patient-Centered Outcomes Research Institute.

Comparison of Heart Team vs Interventional Cardiologist Recommendations for the Treatment of Patients With Multivessel Coronary Artery Disease

IMPORTANCE

Although the heart team approach is recommended in revascularization guidelines, the frequency with which heart team decisions differ from those of the original treating interventional cardiologist is unknown.

OBJECTIVE

To examine the difference in decisions between the heart team and the original treating interventional cardiologist for the treatment of patients with multivessel coronary artery disease.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, 245 consecutive patients with multivessel coronary artery disease were recruited from 1 high-volume tertiary care referral center (185 patients were enrolled through a screening process, and 60 patients were retrospectively enrolled from the center's database). A total of 237 patients were included in the final virtual heart team analysis. Treatment decisions (which comprised coronary artery bypass grafting, percutaneous coronary intervention, and medication therapy) were made by the original treating interventional cardiologists between March 15, 2012, and October 20, 2014. These decisions were then compared with pooled-majority treatment decisions made by 8 blinded heart teams using structured online case presentations between October 1, 2017, and October 15, 2018. The randomized members of the heart teams comprised experts from 3 domains, with each team containing 1 noninvasive cardiologist, 1 interventional cardiologist, and 1 cardiovascular surgeon. Cases in which all 3 of the heart team members disagreed and cases in which procedural discordance occurred (eg, 2 members chose coronary artery bypass grafting and 1 member chose percutaneous coronary intervention) were discussed in a face-to-face heart team review in October 2018 to obtain pooled-majority decisions. Data were analyzed from May 6, 2019, to April 22, 2020.

MAIN OUTCOMES AND MEASURES

The Cohen κ coefficient between the treatment recommendation from the heart team and the treatment recommendation from the original treating interventional cardiologist.

RESULTS

Among 234 of 237 patients (98.7%) in the analysis for whom complete data were available, the mean (SD) age was 67.8 (10.9) years; 176 patients (75.2%) were male, and 191 patients (81.4%) had stenosis in 3 epicardial coronary vessels. A total of 71 differences (30.3%; 95% CI, 24.5%-36.7%) in treatment decisions between the heart team and the original treating interventional cardiologist occurred, with a Cohen κ of 0.478 (95% CI, 0.336-0.540; P = .006). The heart team decision was more frequently unanimous when it was concordant with the decision of the original treating interventional cardiologist (109 of 163 cases [66.9%]) compared with when it was discordant (28 of 71 cases [39.4%]; P < .001). When the heart team agreed with the original treatment decision, there was more agreement between the heart team interventional cardiologist and the original treating interventional cardiologist (138 of 163 cases [84.7%]) compared with when the heart team disagreed with the original treatment decision (14 of 71 cases [19.7%]); P < .001). Those with an original treatment of coronary artery bypass grafting, percutaneous coronary intervention, and medication therapy, 32 of 148 patients [22.3%], 32 of 71 patients [45.1%], and 6 of 15 patients [40.0%], respectively, received a different treatment recommendation from the heart team than the original treating interventional cardiologist; the difference across the 3 groups was statistically significant (P = .002).

CONCLUSIONS AND RELEVANCE

The heart team's recommended treatment for patients with multivessel coronary artery disease differed from that of the original treating interventional cardiologist in up to 30% of cases. This subset of cases was associated with a lower frequency of unanimous decisions within the heart team and less concordance between the interventional cardiologists; discordance was more frequent when percutaneous coronary intervention or medication therapy were considered. Further research is needed to evaluate whether heart team decisions are associated with improvements in outcomes and, if so, how to identify patients for whom the heart team approach would be beneficial.

Examining Coronary Revascularization Practice Patterns for Diabetics: Perceived Barriers, Facilitators, and Implications for Knowledge Translation

BACKGROUND

The FREEDOM trial provided robust evidence that coronary artery bypass grafting (CABG) was superior to percutaneous coronary intervention (PCI) for coronary revascularization in patients with diabetes mellitus (DM) and multivessel coronary artery disease (MV-CAD). The present study examined practice pattern changes and perceived barriers and facilitators to implementing FREEDOM trial evidence in British Columbia (BC).

METHODS

Using a population-based database of cardiac procedures in BC, PCI:CABG ratios from 2007-2014 were compared before and after publication of the FREEDOM trial in the 4 tertiary cardiac centres that provided both CABG and PCI. Surveys of barriers and facilitators to implementation of evidence in practice were completed by 57 health care providers (HCPs) attending educational outreach sessions conducted in 2016-17 at 5 tertiary cardiac centres in BC.

RESULTS

The overall PCI:CABG ratio declined from 1.59 (95% confidence interval [CI] 1.48-1.70, range 1.16-1.86) before publication to 0.88 (95% CI 0.75-1.01, range 0.56-0.82) after publication (P < 0.01). This decline from before to after publication was significant in 3 centres, but not in the fourth centre (from 1.62 to 1.49; P = 0.61). Barriers were identified at the levels of evidence (applicability, credibility), HCP (awareness/knowledge, practice behaviours), patient (knowledge/misconceptions, preferences), and systems (siloing of care, financial disincentives, resource limitations, geography). Facilitators were additional studies/guidelines, education/dissemination, shared decision making, a heart team approach, changes to remuneration models, and increased resources.

CONCLUSIONS

Following publication of the FREEDOM trial, the proportion of patients with DM and MV-CAD undergoing CABG increased in BC; however, practice patterns varied across cardiac centres. HCPs attributed these practice variations to multilevel barriers and facilitators. Future knowledge translation strategies should be multifaceted and tailored to identified determinants.

Age, Not Sex, Modifies the Effect of Frailty on Long-term Outcomes After Cardiac Surgery

OBJECTIVE

To examine the prevalence of frailty in surgical patients and determine whether age and sex modify the relationship between frailty and long-term mortality.

BACKGROUND

Frailty is a complex and prevalent clinical syndrome. The cardiac surgery literature consists mostly of small, single-center studies, and the epidemiology of frailty remains to be fully elucidated in a real-world surgical population.

METHODS

This retrospective cohort study included patients who underwent coronary artery bypass grafting, and/or aortic, mitral or tricuspid valve surgery in Ontario, Canada, between 2008 and 2016. The primary outcome was all-cause mortality. Survival probabilities were calculated using the Kaplan-Meier method, and the association of covariates with the hazard of death was assessed using multivariable Cox proportional hazard models. Frailty was assessed using the Johns Hopkins Adjusted Clinical Groups frailty-defining diagnoses indicator.

RESULTS

Of 72,824 patients, 11,685 (16%) were frail. At median 5 ± 2 years of follow-up, 2921 (25.0%) frail patients and 8637 (14.1%) non-frail patients had died [adjusted hazard ratio 1.60; 95% confidence interval (CI), 1.53-1.68]. The adjusted hazard ratio was highest in patients who underwent isolated mitral (2.18; 95% CI, 1.71-2.77) and mitral + aortic valve surgery (1.85; 95% CI, 1.33-2.58) and lowest after coronary artery bypass grafting + mitral valve surgery (1.38; 95% CI, 1.11-1.70). Age, but not sex, modified the effect of frailty on mortality; such that the rate of death decreased linearly with increasing patient age.

CONCLUSIONS

We observed a high prevalence of frailty in patients undergoing cardiac surgery, and a statistically significant association between frailty and long-term mortality after cardiac procedures. Importantly, the rate of death was inversely proportional to age, such that frailty had a stronger adverse impact on younger patients. Our findings highlight the need to incorporate frailty into the preoperative risk stratification and investigate strategies to support younger patients who are frail.

Sex differences after coronary artery bypass grafting with a second arterial conduit

OBJECTIVES

Double arterial conduit use during coronary artery bypass grafting is associated with improved clinical outcomes compared with single arterial conduits in the general population. However, the sex-specific outcomes of this strategy remain unknown and are needed to inform sex-specific revascularization guidelines.

METHODS

We conducted a population-based, retrospective cohort study of all Ontarians who underwent primary isolated coronary artery bypass grafting with single arterial conduits or double arterial conduits between October 2008 and September 2017. The primary outcome was all-cause mortality. Secondary outcomes included major adverse cardiac and cerebrovascular events, defined as a composite of myocardial infarction, heart failure hospitalization, repeat revascularization, and stroke. We used inverse probability of treatment weighting to account for group imbalances.

RESULTS

A total of 9135 women and 36,748 men underwent coronary artery bypass grafting. At 30 days, there was no between-group difference in mortality or major adverse cardiac and cerebrovascular events in men. However, among women, a double arterial conduit was associated with an increased rate of 30-day death (hazard ratio, 1.48; 95% confidence interval, 1.23-1.79) and major adverse cardiac and cerebrovascular events (hazard ratio, 1.32; 95% confidence interval, 1.14-1.51). The risk of medium-term mortality with double arterial conduits was less in men (hazard ratio, 0.88; 95% confidence interval, 0.84-0.92) and women (hazard ratio, 0.87; 95% confidence interval, 0.81-0.94), as was the medium-term risk of major adverse cardiac and cerebrovascular events (hazard ratio, 0.91; 95% confidence interval, 0.87-0.94) [men]; hazard ratio, 0.91; 95% confidence interval, 0.86-0.97) [women]). The incremental improvement in 9-year survival was 4.0% in women with a double arterial conduit and 0.9% in men.

CONCLUSIONS

Double arterial conduit is associated with better medium-term survival and cardiovascular outcomes in both sexes. Double arterial conduits are associated with increased perioperative risk in women, but the medium-term benefit is greater than in men.

Factors associated with the rates of coronary artery bypass graft and percutaneous coronary intervention

BACKGROUND

Korea has seen a rapid increase in the use of percutaneous coronary intervention (PCI) with the ratio of PCI to coronary artery bypass graft (CABG) the highest in the world. This study was performed to examine the factors associated with the rates of CABG and PCI.

METHODS

The data were acquired from the National Health Insurance database in Korea in 2013. We calculated the age-sex standardized rates of CABG and PCI. We examined the factors associated with the CABG and PCI rates by performing a regression analysis.

RESULTS

The rate of CABG showed a negative association with the deprivation index score, and other factors, such as the number of providers or hospital beds, did not show any significant association with the CABG rate. The rate of PCI had a strong negative association with the number of cardiothoracic surgeons and a strong positive association with the number of hospital beds.

CONCLUSIONS

The positive association between the PCI rate and the number of hospital beds suggests that the use of PCI may be driven by the supply of beds, and the inverse association between the PCI rate and the number of cardiothoracic surgeons indicates the overuse of PCI due to lack of the providers of CABG. Policy measures should be taken to optimize the use of revascularization procedures, the choice of which should primarily be based on the patient's need.

Sex Differences in Long-Term Survival After Major Cardiac Surgery: A Population-Based Cohort Study

Background

Little attention has been paid to the importance of sex in the long‐term prognosis of patients undergoing cardiac surgery.

Methods and Results

We conducted a retrospective cohort study of Ontario residents, aged ≥40 years, who underwent coronary artery bypass grafting (CABG) and/or aortic, mitral, or tricuspid valve surgery between October 1, 2008, and December 31, 2016. The primary outcome was all‐cause mortality. The mortality rate in each surgical group was calculated using the Kaplan‐Meier method. The risk of death was assessed using multivariable Cox proportional hazard models. Sex‐specific mortality risk factors were identified using multiplicative interaction terms. A total of 72 824 patients were included in the study (25% women). The median follow‐up period was 5 (interquartile range, 3–7) years. The long‐term age‐standardized mortality rate was lowest in patients who underwent isolated CABG and highest among those who underwent combined CABG/multiple valve surgery. Women had significantly higher age‐standardized mortality rate than men after CABG and combined CABG/mitral valve surgery. Men had lower rates of long‐term mortality than women after isolated mitral valve repair, whereas women had lower rates of long‐term mortality than men after isolated mitral valve replacement. We observed a statistically significant association between female sex and long‐term mortality after adjustment for key risk factors.

Conclusions

Female sex was associated with long‐term mortality after cardiac surgery. Perioperative optimization and long‐term follow‐up should be tailored to younger women with a history of myocardial infarction and percutaneous coronary intervention and older men with a history of chronic obstructive pulmonary disease and depression.

Profiling Hospital Performance on the Basis of Readmission After Transcatheter Aortic Valve Replacement in Ontario, Canada

Background

Readmission rates are a widely accepted quality indicator. Our objective was to develop models for calculating case‐mixed adjusted readmission rates after transcatheter aortic valve replacement for the purpose of profiling hospitals.

Methods and Results

In this population‐based study in Ontario, Canada, we identified all transcatheter aortic valve replacement procedures between April 1, 2012, and March 31, 2016. For each hospital, we first calculated 30‐day and 1‐year risk‐standardized (predicted versus expected) readmission rates, using 2‐level hierarchical logistic regression models, including clustering of patients within hospitals. We also calculated the risk‐adjusted (observed versus expected) readmission rates, accounting for the competing risk of death using a Fine‐Gray competing risk model. We categorized hospitals into 3 groups: those performing worse than expected, those performing better than expected, or those performing as expected, on the basis of whether the 95% CI was above, below, or included the provincial average readmission rate respectively. Our cohort consisted of 2129 transcatheter aortic valve replacement procedures performed at 10 hospitals. The observed readmission rate was 15.4% at 30 days and 44.2% at 1 year, with a range of 10.9% to 21.7% and 38.8% to 55.0%, respectively, across hospitals. Incorporating the competing risk of death translated into meaningful different results between models; as such, we concluded that the risk‐adjusted readmission rate was the preferred metric. On the basis of the 30‐day risk‐adjusted readmission rate, all hospitals performed as expected, with a 95% CI that included the provincial average. However, we found that there was significant variation in 1‐year risk‐adjusted readmission rate.

Conclusions

There is significant interhospital variation in 1‐year adjusted readmission rates among hospitals, suggesting that this should be a focus for quality improvement efforts in transcatheter aortic valve replacement.

Importance of Nonobstructive Coronary Artery Disease in the Prognosis of Patients With Heart Failure

OBJECTIVES

This study sought to examine the prognostic significance of nonobstructive coronary artery disease (CAD) in patients with heart failure (HF), as a distinct category apart from those with normal coronary arteries.

BACKGROUND

Individuals with HF are often dichotomized into ischemic versus nonischemic categories according to the underlying etiology. This binary classification creates a heterogeneous group, combining individuals with nonobstructive CAD with those with normal coronary arteries under the nonischemic label.

METHODS

A cohort of individuals with HF and reduced ejection fraction undergoing invasive coronary angiography was examined and linked to administrative databases for outcomes evaluation. Patients were divided into those with normal coronary arteries, nonobstructive disease, and obstructive disease. The primary outcome was the composite of cardiovascular death, nonfatal acute myocardial infarction, nonfatal stroke, or HF hospitalization.

RESULTS

Of 12,814 individuals, 2,656 (20.7%) had normal coronary arteries, 2,254 (17.6%) had nonobstructive CAD, and 7,904 (61.7%) had obstructive CAD. The risk of the primary outcome was increased in the nonobstructive group (hazard ratio [HR]: 1.17; 95% confidence interval [CI]: 1.04 to 1.32; p = 0.01) relative to those with normal coronary arteries. Nonobstructive CAD was associated with an increased hazard of cardiovascular death (HR: 1.82; 95% CI: 1.27 to 2.62; p = 0.001) and death of any cause (HR: 1.18; 95% CI: 1.05 to 1.33; p = 0.005). There were no significant differences in the rate of acute myocardial infarction, stroke, or HF hospitalization.

CONCLUSIONS

Among HF patients with reduced ejection fraction, the presence of nonobstructive CAD was independently associated with an increased hazard of the primary composite outcome and death of any cause.

Variation in Revascularization Practice and Outcomes in Asymptomatic Stable Ischemic Heart Disease

OBJECTIVES

The aims of this study were to assess variation in revascularization of asymptomatic patients with stable ischemic heart disease, identify the predictors of variation, and determine if it was associated with clinical outcomes.

BACKGROUND

Management of stable ischemic heart disease in asymptomatic patients with obstructive coronary artery disease is controversial, potentially leading to practice variation.

METHODS

A retrospective observational cohort study was performed using population-based data from Ontario, Canada, in patients with asymptomatic stable ischemic heart disease and obstructive coronary artery disease. The cohort was divided on the basis of treatment strategy: revascularization or medical therapy. Hospitals were allocated into tertiles of their revascularization ratio. Outcomes included death and nonfatal myocardial infarction. Hierarchical logistic regression was used to assess the predictors of revascularization, with median odds ratios used to quantify variation. Proportional hazards models were used to determine the association between management strategy and outcomes.

RESULTS

The cohort included 9,897 patients, 47% treated with medical therapy and 53% with revascularization. Between hospitals, 2-fold variation existed in the ratio of revascularized to medically treated patients. However, the variation across hospitals was not explained by patient, physician, or hospital factors (median odds ratio in null model: 1.25; median odds ratio in full model: 1.31). Revascularization was associated with a hazard ratio of 0.81 (95% confidence interval: 0.69 to 0.96) for death and a hazard ratio of 0.58 (95% confidence interval: 0.46 to 0.73) for myocardial infarction, with this benefit consistent across tertiles of revascularization ratio.

CONCLUSIONS

Wide variation was observed in revascularization practice that was not explained by known factors. Despite this variation, a clinical benefit was observed with revascularization that was consistent across hospitals.

Temporal Trends in Fractional Flow Reserve Use in Patients Undergoing Coronary Angiography: A Population-Based Study

Background

Invasive fractional flow reserve (FFR) has emerged as an important tool to identify a subset of patients in whom coronary revascularization may be beneficial. Our objective was to evaluate temporal trends in FFR use.

Methods

We identified all coronary angiograms in the CorHealth Ontario Cardiac Registry between the years 2010 and 2015. The primary and secondary outcomes were the age- and sex-adjusted monthly rate of FFR per 100,000 population and per 100 angiograms, respectively. Piecewise regression analyses were used to evaluate the temporal trends in FFR use for the entire cohort, and then stratified by indication (stable coronary artery disease [CAD]) vs acute coronary syndrome [ACS]).

Results

The study cohort included 379,688 angiograms, of which 122,571 were for stable CAD (32%) and 134,769 were for ACS (36%). Monthly age- and sex-adjusted FFR use rates increased significantly over the study period, from 0.4 to 2.3 per 100,000 people per month. The monthly FFR use rate per 100 angiograms increased from 0.9 to 4.9 per 100 angiograms per month; however, the proportion of positive FFR (< 0.8) results was relatively constant at 28%. There was a more dramatic increase in the use of FFR in the population with stable CAD (1.1 to 8.0 per 100 angiograms/month) compared with the population with ACS (0.6 to 4.5 per 100 angiograms/month).

Conclusions

There was a > 5-fold increase in the use of FFR in patients across Ontario, which was predominantly driven by use in stable CAD. Case selection for FFR use was relatively unchanged with approximately one-quarter of FFR cases being positive over time.

Profiling Hospital Performance Based on Mortality After Transcatheter Aortic Valve Replacement in Ontario, Canada

BACKGROUND

Public reporting of hospital-level outcomes is increasingly common as a means to target quality improvement strategies to ensure the delivery of optimal care. Despite the rapid dissemination of transcatheter aortic valve replacement (TAVR), there is a paucity of reliable case-mix adjustment models for hospital profiling in TAVR. Our objective was to develop and evaluate different models for calculating risk-standardized all-cause mortality rates (RSMRs) post-TAVR.

METHODS AND RESULTS

In this population-based study in Ontario, Canada, we identified all patients who underwent a TAVR procedure between April 1, 2012, and March 31, 2016. For each hospital, we calculated 30-day and 1-year RSMR, using 2-level hierarchical logistic regression models that accounted for patient-specific demographic and clinical characteristics, as well as the clustering of patients within the same hospital using a hospital-specific random effects. We classified each hospital into one of 3 groups: performing worse than expected, better than expected, or performing as expected, based on whether the 95% CI of the RSMR was above, below, or included the provincial average mortality rate, respectively. Our cohort consisted of 2129 TAVR procedures performed at 10 hospitals. The observed mortality was 7.0% at 30 days and 16.4% at 1 year, with a range of 4% to 10% and 8% to 22%, respectively, across hospitals. We developed case-mix adjustment models using 28 clinically relevant variables. Using 30-day and 1-year RSMR to profile each hospital, we found that all hospitals performed as expected, with 95% CI that included the provincial average.

CONCLUSIONS

We found no significant interhospital variation in RSMR among hospitals, suggesting that quality improvement efforts should be directed at aspects other than the variation in observed mortality.

Disability-free survival after coronary artery bypass grafting in women and men with heart failure

Objective

Heart failure (HF) impairs survival post coronary artery bypass grafting (CABG), but little is known about the postoperative quality of life (QoL) in patients with HF. We derived a patient-centred QoL surrogate and assessed the impact of different HF subtypes on this surrogate in the year post-CABG.

Methods

We surveyed 3112 cardiovascular patients to derive a patient-centred disability outcome and studied this outcome in a population-based cohort. We defined preserved ejection fraction as ≥50% and reduced ejection fraction as <50%. The primary outcome was disability, defined according to compiled patient-derived values. The secondary outcomes consisted of each individual component of disability, and death. The incidence of disability was calculated using cumulative incidence functions, with death as a competing risk. We identified predictors of disability using cause-specific hazard models.

Results

Patient-derived disability outcome consisted of stroke, nursing home admission and recurrent hospitalisations. When applied to 40 083 CABG patients (20.6% women), the incidence of disability was 5.4% while the incidence of death was 3.7% in the year post-CABG. Female sex was associated with an adjusted HR of 1.25 (95% CI 1.13 to 1.37) for disability. Women with HF with preserved ejection fraction had an adjusted HR of 1.73 (95% CI 1.52 to 1.98) for disability.

Conclusions

Disability was a more frequent complication than death in the year post-CABG. Women experienced higher burden of disability than men, and female sex and the presence of HF were important disability risk factors. Efforts should be dedicated to disability risk prediction to enable patient-centred operative decision-making and to developing sex-specific treatment strategies to improve outcomes.

Association of Frailty and Long-Term Survival in Patients Undergoing Coronary Artery Bypass Grafting

BACKGROUND

Frailty is increasing in prevalence and poses a formidable challenge for clinicians. The cardiac surgery literature consists primarily of small single-center studies with limited follow-up, and the epidemiological features of frailty remain to be elucidated in long-term follow-up.

METHODS AND RESULTS

We conducted a population-based, retrospective, cohort study in Ontario, Canada, between 2008 and 2015. Frailty was defined using the Johns Hopkins Adjusted Clinical Groups frailty indicator (a multidimensional instrument validated for research using administrative data). The primary outcome was mortality. Mortality rates were calculated using the Kaplan-Meier method. The hazard of death was assessed using a multivariable Cox proportional hazard model. Of 40 083 patients, 8803 (22%) were frail. At 4±2 years of follow-up, age- and sex-standardized mortality rate per 1000 person-years was higher in frail (33; 95% confidence interval, 29-36) compared with nonfrail (22; 95% confidence interval, 19-24) patients. Frailty was associated with an increased risk of long-term mortality (adjusted hazard ratio, 1.20; 95% confidence interval, 1.12-1.28) and greater differences in the survival of patients between 40 and 74 years of age than in those who were ≥85 years old.

CONCLUSIONS

Frailty was present in a large proportion of patients undergoing coronary artery bypass grafting and was independently associated with long-term mortality. The adjusted risk of frailty-related death was inversely proportional to age. Our findings highlight the need for more comprehensive preoperative risk stratification models to assist with optimal selection of operative candidates. In addition, we identified the <75 years age group as a potential target for comprehensive preoperative optimization programs, such as cardiac prehabilitation, nutritional augmentation, and psychosocial support.

Prevalence and Long-Term Survival After Coronary Artery Bypass Grafting in Women and Men With Heart Failure and Preserved Versus Reduced Ejection Fraction

BACKGROUND

Heart failure (HF) with reduced ejection fraction (rEF) is a widely regarded prognosticator after coronary artery bypass grafting. HF with preserved ejection fraction (pEF) accounts for up to half of all HF cases and is associated with considerable morbidity and mortality in hospitalized cohorts. However, HFpEF outcomes have not been elucidated in cardiac surgical patients. We investigated the prevalence and outcomes of HFpEF and HFrEF in women and men following coronary artery bypass grafting.

METHODS AND RESULTS

We conducted a retrospective cohort study in Ontario, Canada, between October 1, 2008, and March 31, 2015, using Cardiac Care Network and Canadian Institute of Health Information data. HF is captured through a validated population-based database of all Ontarians with physician-diagnosed HF. We defined pEF as ejection fraction ≥50% and rEF as ejection fraction <50%. The primary outcome was all-cause mortality. Analyses were stratified by sex. Mortality rates were calculated using Kaplan-Meier method. The relative hazard of death was assessed using multivariable Cox proportional hazard models. Of 40 083 patients (20.6% women), 55.5% had pEF without HF, 25.7% had rEF without HF, 6.9% had HFpEF, and 12.0% had HFrEF. Age-standardized HFpEF mortality rates at 4±2 years of follow-up were similar in women and men. HFrEF standardized HFpEF mortality rates were higher in women than men.

CONCLUSIONS

We found a higher prevalence and poorer prognosis of HFpEF in women. A history of HF was a more important prognosticator than ejection fraction. Preoperative screening and extended postoperative follow-up should be focused on women and men with HF rather than on rEF alone.

Information needs of generalists and specialists using online best-practice algorithms to answer clinical questions

Objective

To better understand clinician information needs and learning opportunities by exploring the use of best-practice algorithms across different training levels and specialties.

Methods

We developed interactive online algorithms (care process models [CPMs]) that integrate current guidelines, recent evidence, and local expertise to represent cross-disciplinary best practices for managing clinical problems. We reviewed CPM usage logs from January 2014 to June 2015 and compared usage across specialty and provider type.

Results

During the study period, 4009 clinicians (2014 physicians in practice, 1117 resident physicians, and 878 nurse practitioners/physician assistants [NP/PAs]) viewed 140 CPMs a total of 81 764 times. Usage varied from 1 to 809 views per person, and from 9 to 4615 views per CPM. Residents and NP/PAs viewed CPMs more often than practicing physicians. Among 2742 users with known specialties, generalists ( N  = 1397) used CPMs more often (mean 31.8, median 7 views) than specialists ( N  = 1345; mean 6.8, median 2; P  < .0001). The topics used by specialists largely aligned with topics within their specialties. The top 20% of available CPMs (28/140) collectively accounted for 61% of uses. In all, 2106 clinicians (52%) returned to the same CPM more than once (average 7.8 views per topic; median 4, maximum 195). Generalists revisited topics more often than specialists (mean 8.8 vs 5.1 views per topic; P  < .0001).

Conclusions

CPM usage varied widely across topics, specialties, and individual clinicians. Frequently viewed and recurrently viewed topics might warrant special attention. Specialists usually view topics within their specialty and may have unique information needs.

Outcome and selection of revascularization strategy in left main coronary artery stenosis

OBJECTIVES

To investigate clinical outcome in unselected real-life patients with unprotected left main coronary artery (ULMCA) stenosis and determine factors associated with selection of revascularization strategy.

DESIGN

Consecutive patients with ULMCA stenosis at our institution in 2009-2013 (n = 308) were retrospectively analyzed with propensity score adjusted Cox proportional hazards models for outcome. Baseline characteristics in relation to selection of revascularization strategy were analyzed with multivariate logistic regression.

RESULTS

Patients that underwent PCI (n = 94) had a higher risk of major adverse cardiac and cerebrovascular events (MACCE; adjusted HR 2.13 [95% CI 1.08-4.19]) than patients that had CABG surgery but there was no difference in the combination of death and MI (adjusted HR 1.17 [95% CI 0.50-2.75]). Later year of index angiography, age, Euroscore II and angiographer favoring PCI was associated with PCI as revascularization strategy. Higher SYNTAX score, higher systolic blood pressure and angiographer favoring CABG was associated with CABG.

CONCLUSIONS

In consecutive patients with ULMCA stenosis PCI is associated with higher MACCE rates than CABG but there is no difference in death and MI. Later year of index angiography, higher age, lower systolic blood pressure, higher predicted per-procedural surgical risk, less complex coronary anatomy and angiographer favoring PCI increased the probability of revascularization with PCI instead of CABG.

Variation in Management of Patients With Obstructive Coronary Artery Disease: Insights From the Veterans Affairs Clinical Assessment and Reporting Tool (VA CART) Program

BACKGROUND

Little is known about facility-level variation in the use of revascularization procedures for the management of stable obstructive coronary artery disease. Furthermore, it is unknown if variation in the use of coronary revascularization is associated with use of other cardiovascular procedures.

METHODS AND RESULTS

We evaluated all elective coronary angiograms performed in the Veterans Affairs system between September 1, 2007, and December 31, 2011, using the Clinical Assessment and Reporting Tool and identified patients with obstructive coronary artery disease. Patients were considered managed with revascularization if they received percutaneous coronary intervention (PCI) or coronary artery bypass grafting within 30 days of diagnosis. We calculated risk-adjusted facility-level rates of overall revascularization, PCI, and coronary artery bypass grafting. In addition, we determined the association between facility-level rates of revascularization and post-PCI stress testing. Among 15 650 patients at 51 Veterans Affairs sites who met inclusion criteria, the median rate of revascularization was 59.6% (interquartile range, 55.7%-66.7%). Across all facilities, risk-adjusted rates of overall revascularization varied from 41.5% to 88.1%, rate of PCI varied from 23.2% to 80.6%, and rate of coronary artery bypass graftingvariedfrom 7.5% to 36.5%. Of 6179 patients who underwent elective PCI, the median rate of stress testing in the 2 years after PCI was 33.7% (interquartile range, 30.7%-47.1%). There was no evidence of correlation between facility-level rate of revascularization and follow-up stress testing.

CONCLUSIONS

Within the Veterans Affairs system, we observed large facility-level variation in rates of revascularization for obstructive coronary artery disease, with variation driven primarily by PCI. There was no association between facility-level use of revascularization and follow-up stress testing, suggesting use rates are specific to a particular procedure and not a marker of overall facility-level use.

Management of Chronic Total Coronary Occlusion in Stable Ischemic Heart Disease by Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting Versus Medical Therapy

Coronary chronic total occlusions (CTOs) are found in approximately 20% of angiograms. We sought to assess the variation in the management of patients with CTOs and to compare the clinical outcomes of CTO lesions with those of non-CTO lesions. We conducted a population-based cohort study and included all patients with stable angina who underwent cardiac catheterization from October 1, 2012, to June 30, 2013, in Ontario, Canada. The primary outcome was a composite of mortality and hospitalization for myocardial infarction. A total of 7,864 patients were included, of whom 2,279 (29%) had a CTO. There were substantial differences in revascularization rates for patients with CTOs across hospitals in Ontario (44.9% to 94.1%). Revascularization was associated with improved outcomes in the overall cohort. Although the advantage of coronary artery bypass grafting over medical therapy was consistent in both patients with CTOs and patients without CTOs, the benefit of percutaneous coronary intervention (PCI) was limited to patients without CTOs (hazard ratio 0.56, 95% confidence interval 0.40- to 0.78), with no difference in patients with CTOs. The CTO lesion, however, was revascularized in few of the PCI cases (41.1%), with PCI limited to the non-CTO lesion in most patients.

Comparison of Anatomic and Clinical Outcomes in Patients Undergoing Alternative Initial Noninvasive Testing Strategies for the Diagnosis of Stable Coronary Artery Disease

Background

The optimal initial noninvasive diagnostic testing strategy for stable coronary artery disease (CAD) is unknown. Although American guidelines recommend an exercise stress test as the first‐line test, European guidelines suggest that stress imaging (myocardial perfusion imaging or stress echocardiography) or coronary computed tomography angiography may be preferable. Understanding the relationship between the initial strategy and downstream yield of obstructive CAD and major adverse cardiac events may provide insight as to the optimal strategy.

Methods and Results

We conducted a population‐based retrospective cohort study of adults in Ontario, Canada, using health administrative and clinical data. The relationship between the initial testing strategy and obstructive CAD on invasive angiography was examined. Patients were then followed from their angiogram onward to determine whether they developed a composite end point of major adverse cardiac events. After adjusting for covariates, patients with initial myocardial perfusion imaging (odds ratio: 0.92; 95% confidence interval, 0.85, 1.00), coronary computed tomography angiography (odds ratio: 1.51; 95% confidence interval, 0.91, 2.49), or stress echo (odds ratio: 0.95; 95% confidence interval, 0.84, 1.08) did not a have significantly different yield of obstructive CAD compared with those with an initial exercise stress test. Furthermore, there was no significant difference in downstream major adverse cardiac events after invasive angiography among the 4 initial testing strategies after adjusting for clinically relevant covariates.

Conclusions

Our study found no evidence to suggest significant differences in either yield of obstructive CAD or downstream major adverse cardiac events in patients undergoing an initial noninvasive testing strategy with stress or anatomical imaging compared with those undergoing an initial exercise stress test.

Hospital variation in treatment and outcomes in acute coronary syndromes: Insights from the Alberta Contemporary Acute Coronary Syndrome Patients Invasive Treatment Strategies (COAPT) study

BACKGROUND

We examined variation in hospital treatment and its relationship to clinical outcome in a large population-based cohort of ACS patients within a single payer-government funded health care system.

METHODS

Patients hospitalized in 106 hospitals in Alberta, Canada with a primary diagnosis of ACS were included (July 1, 2010-March 31, 2013) with comparisons made across the three cardiac catheterization-capable hospitals (Sites A-C). Cox proportional-hazard regression models were used to examine the multivariable-adjusted association between site and 1-year death or repeat cardiovascular (CV) hospitalization (primary endpoint).

RESULTS

Of 14,155 patients, 1938 (13.7%) were admitted to a community hospital without transfer to an invasive hospital (10.7% in-hospital death). The remaining were admitted (n=4514, 36.9%) or transferred (n=7703, 63.1%) to an invasive hospital (A:5480; B:3621; C:3116) where 11,247 (92.1%) underwent catheterization. Comorbidities and angiographic disease burden differed across sites. Variation in 30-day revascularization (PCI: 71.3%, 72.0%, 68.7%, p<0.001; CABG: 6.2%, 6.4%, 9.3%, p<0.001) and drug-eluting stent use for PCI (24.3%, 54.6%, 50.5%, p<0.001) were observed. After adjustment for patient demographics and comorbidities, variation in rates of 1-year death or CV hospitalization was observed among those with 30-day revascularization (p(interaction)<0.001; B versus A: HR 0.78, 95%CI 0.66-0.91; C versus A: HR 0.77, 95%CI 0.65-0.91; B versus C: HR 1.01, 95%CI 0.84-1.21).

CONCLUSIONS

Despite a government funded health system, we have shown variation in hospital treatment exists. Following adjustment hospital site was associated with differences in clinical outcome within 1year. Hence, further efforts may be warranted to help address potential disparities in ACS care.

The Effect of Geographic Units of Analysis on Measuring Geographic Variation in Medical Services Utilization

Objectives:

We aimed to evaluate the effect of geographic units of analysis on measuring geographic variation in medical services utilization. For this purpose, we compared geographic variations in the rates of eight major procedures in administrative units (districts) and new areal units organized based on the actual health care use of the population in Korea.

Methods:

To compare geographic variation in geographic units of analysis, we calculated the age–sex standardized rates of eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee-replacement surgery, caesarean section, hysterectomy, computed tomography scan, and magnetic resonance imaging scan) from the National Health Insurance database in Korea for the 2013 period. Using the coefficient of variation, the extremal quotient, and the systematic component of variation, we measured geographic variation for these eight procedures in districts and new areal units.

Results:

Compared with districts, new areal units showed a reduction in geographic variation. Extremal quotients and inter-decile ratios for the eight procedures were lower in new areal units. While the coefficient of variation was lower for most procedures in new areal units, the pattern of change of the systematic component of variation between districts and new areal units differed among procedures.

Conclusions:

Geographic variation in medical service utilization could vary according to the geographic unit of analysis. To determine how geographic characteristics such as population size and number of geographic units affect geographic variation, further studies are needed.

Evaluation of Geographic Indices Describing Health Care Utilization

Objectives

The accurate measurement of geographic patterns of health care utilization is a prerequisite for the study of geographic variations in health care utilization. While several measures have been developed to measure how accurately geographic units reflect the health care utilization patterns of residents, they have been only applied to hospitalization and need further evaluation. This study aimed to evaluate geographic indices describing health care utilization.

Methods

We measured the utilization rate and four health care utilization indices (localization index, outflow index, inflow index, and net patient flow) for eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee replacement surgery, caesarean sections, hysterectomy, computed tomography scans, and magnetic resonance imaging scans) according to three levels of geographic units in Korea. Data were obtained from the National Health Insurance database in Korea. We evaluated the associations among the health care utilization indices and the utilization rates.

Results

In higher-level geographic units, the localization index tended to be high, while the inflow index and outflow index were lower. The indices showed different patterns depending on the procedure. A strong negative correlation between the localization index and the outflow index was observed for all procedures. Net patient flow showed a moderate positive correlation with the localization index and the inflow index.

Conclusions

Health care utilization indices can be used as a proxy to describe the utilization pattern of a procedure in a geographic unit.

Relation between initial treatment strategy in stable coronary artery disease and 1-year costs in Ontario: a population-based cohort study

BACKGROUND

Cardiovascular disease is costly, and annual expenditures are projected to increase. Our objective was to examine the variation in patient-level costs and identify drivers of cost in patients with stable coronary artery disease.

METHODS

In this retrospective cohort study using administrative databases in Ontario, Canada, we identified all patients with stable coronary artery disease after index angiography between Oct. 1, 2008, and Sept. 30, 2011. We excluded patients with a myocardial infarction within 90 days before the index, with normal coronaries, or with mild coronary disease. We categorized hospitals into low, medium or high revascularization ratio centres. The primary outcome was cumulative 1-year health care costs. A hierarchical generalized linear model identified patient, physician and hospital characteristics associated with patient costs, with 2 main covariates of interest: treatment allocation (medical v. percutaneous coronary intervention v. coronary artery bypass grafting) and hospital revascularization ratio.

RESULTS

A total of 183 630 angiography procedures were performed in Ontario during the study period. The final cohort included 39 126 patients with stable coronary artery disease, of which 15 138 received medical treatment and 23 988 received revascularization. The mean 1-year cost was $24 026 (interquartile range $8235-$30 511). The mean costs for medical management and revascularization were $18 069 and $27 786, respectively. The strongest predictor of costs was revascularization (percutaneous coronary intervention: cost ratio 1.27, 95% CI [confidence interval] 1.24-1.31; coronary artery bypass grafting: cost ratio 2.62, 95% CI 2.53-2.71). Hospital revascularization ratio did not significantly affect costs. There was no significant interaction between treatment and revascularization ratio.

INTERPRETATION

Most health care costs were due to acute care hospital admissions, and costs were higher for patients undergoing revascularization than medical therapy. This study suggests that treatment decision has a substantial impact on health care resources.