Which risk score best predicts perioperative outcomes in nonvalvular atrial fibrillation patients undergoing noncardiac surgery?

The CHA2DS2-VASC Score Predicts Mortality in Patients Undergoing Coronary Angiography

BACKGROUND

The CHA2DS2-VASC score is used to predict the risk of thromboembolic complications in patients with atrial fibrillation (AF). We hypothesized that the CHA2DS2-VASC score can be used to predict mortality in patients undergoing coronary angiography.

METHODS AND RESULTS

This was a prospective study of 990 patients undergoing coronary angiography. The median follow-up was 2294 days. The patients were categorized into two groups according to their CHA2DS2-VASC score: group I had scores <4 and group II had scores ≥4 (527 (53.2%) and 463 (46.8%), respectively). A Kaplan-Meier analysis demonstrated a significant association between the CHA2DS2-VASC score and mortality (69/527 (13.1%) vs. 179/463 (38.7%) for group I vs. group II, respectively, p < 0.0001). The association remained significant in patients with and without AF, reduced and preserved LVEF, normal and reduced kidney function, and with and without ACS (p < 0.009 to p < 0.0001 for all). In the Cox regression model, which combined the CHA2DS2-VASC score, the presence of AF, LVEF, anemia, and renal insufficiency, an elevated CHA2DS2-VASC score of ≥4 was independently associated with higher mortality (HR 2.12, CI 1.29-3.25, p = 0.001).

CONCLUSIONS

The CHA2DS2VASC score is a simple and reliable mortality predictor in patients undergoing coronary angiography and should be used for the initial screening for such patients.

Navigating Antiplatelet Treatment Options for Stroke: Evidence-Based and Pragmatic Strategies

PURPOSE OF REVIEW

The benefit of using antiplatelet monotherapy in acute ischemic stroke and secondary stroke prevention is well established. In the last few years, several large randomized trials showed that the use of short-term dual antiplatelet therapy in particular stroke subtypes may reduce the risk of recurrent ischemic events. The aim of this article is to provide a critical analysis of the current evidence and recommendations for the use of antiplatelet agents for stroke prevention.

RECENT FINDINGS

Long-term therapy with aspirin, clopidogrel, or aspirin plus extended-release dipyridamole is recommended for secondary stroke prevention in patients with noncardioembolic ischemic stroke. Short-term dual antiplatelet therapy with aspirin and clopidogrel is superior to antiplatelet monotherapy in secondary stroke prevention when used in patients with mild noncardioembolic stroke or high-risk transient ischemic attack. Dual therapy, however, is associated with an increased risk of major bleeding, particularly when the treatment is extended for greater than 30 days. Similarly, aspirin plus ticagrelor is superior to aspirin monotherapy for the prevention of recurrent ischemic stroke, although this combination is associated with a higher risk of hemorrhagic complications when compared to other dual antiplatelet regimens. Among patients who carry CYP2C19 genetic polymorphisms associated with a slow bioactivation of clopidogrel, short-term treatment with aspirin plus ticagrelor is superior to aspirin plus clopidogrel for the reduction of recurrent stroke; however, the use of ticagrelor is associated with a higher risk of any bleeding. In patients with symptomatic intracranial stenosis, aggressive medical management in addition to dual antiplatelet therapy up to 90 days is recommended. Antiplatelet therapy has an essential role in the management of ischemic stroke. The specific antiplatelet regimen should be individualized based on the stroke characteristics, time from symptom onset, and patient-specific predisposition to develop hemorrhagic complications.

The Marsden Morbidity Index: the derivation and validation of a simple risk index scoring system using cardiopulmonary exercise testing variables to predict morbidity in high-risk patients having major cancer surgery

Background

Morbidity and mortality risk prediction tools are increasingly being used as part of preoperative assessment of patients presenting for major abdominal surgery. Cardiopulmonary exercise testing (CPET) can predict which patients undergoing major abdominal surgery are at risk of complications. The primary objective of this study was to identify preoperative variables including those derived from CPET, which were associated with inpatient morbidity in high-risk patients following major abdominal cancer surgery. The secondary objective was to use these variables to derive and validate a morbidity risk prediction tool.

Methods

We conducted a retrospective cohort analysis of consecutive adult patients who had CPET as part of their preoperative work-up for major abdominal cancer surgery. Morbidity was a composite outcome, defined by the Clavien-Dindo score and/or the postoperative morbidity survey (POMS) score which was assessed on postoperative day 7. A risk prediction tool was devised using variables from the first analysis which was then applied prospectively to a matched cohort of patients.

Results

A total of 1398 patients were included in the first phase of the analysis between June 2010 and May 2017. Of these, 540 patients (38.6%) experienced postoperative morbidity. CPET variables deemed significant (p < 0.01) were anaerobic threshold (AT), maximal oxygen consumption at maximal exercise capacity (VO2 max), and ventilatory equivalent for carbon dioxide at anaerobic threshold (AT VE/VCO2). In addition to the CPET findings and the type of surgery the patient underwent, eight preoperative variables that were associated with postoperative morbidity were identified. These include age, WHO category, body mass index (BMI), prior transient ischaemic attack (TIA) or stroke, chronic renal impairment, diabetes mellitus, chronic obstructive pulmonary disease (COPD), and cancer stage. Both sets of variables were then combined to produce a validated morbidity risk prediction scoring tool called the Marsden Morbidity Index. In the second phase of the analysis, this tool was applied prospectively to 424 patients between June 2017 and December 2018. With an area under the curve (AUC) of 0.79, this new model had a sensitivity of 74.2%, specificity of 78.1%, a positive predictive value (PPV) of 79.7%, and a negative predictive value of (NPV) of 79%.

Conclusion

Our study showed that of the CPET variables, AT, VO2 max, and AT VE/VCO2 were shown to be associated with postoperative surgical morbidity following major abdominal oncological surgery. When combined with a number of preoperative comorbidities commonly associated with increased risk of postoperative morbidity, we created a useful institutional scoring system for predicting which patients will experience adverse events. However, this system needs further validation in other centres performing oncological surgery.

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery

BACKGROUND

The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this.

OBJECTIVES

Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery.

SEARCH METHODS

We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period.

SELECTION CRITERIA

We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews.

MAIN RESULTS

We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS₂, CHA₂DS₂-VASc, R₂CHADS₂, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively.

AUTHORS' CONCLUSIONS

Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

Impact of individual stroke risk on outcome after Amplatzer left atrial appendage closure in patients with atrial fibrillation

OBJECTIVES

To investigate periprocedural and long-term outcome of left atrial appendage closure (LAAC) using Amplatzer occluders with respect to individual pre-procedural stroke risk.

BACKGROUND

LAAC is a proven strategy for prevention from stroke and bleeding in patients with nonvalvular atrial fibrillation not amenable to oral anticoagulation. Whether individual pre-procedural stroke risk may affect procedural and long-term clinical outcome after LAAC is unclear.

METHODS

Multicenter study of consecutive patients who underwent Amplatzer-LAAC. Using pre-procedural CHADS₂ score, outcomes were compared between a low (0-2 points) and a high stroke risk group (3-6 points).

RESULTS

Five hundred consecutive patients (73.9 ± 10.1 years) who underwent Amplatzer-LAAC. Two hundred and forty eight had preprocedural CHADS₂ score ≤ 2 points (low-risk group) and the remaining 252 patients had 3-6 points (high-risk group). Periprocedural complication rates (6.0% vs. 5.6%, p = .85), procedural success (LAAC without major periprocedural or device-related complications or major para-device leaks: 89.4% vs. 87.9%, p = .74), and 30-day-mortality (2.4% vs. 2.6%, p = .77) were comparable. After 1,346 patient-years (PY), the long-term composite efficacy endpoint (stroke, systemic embolism, cardiovascular, and unexplained death) was reached in 23/653 (3.5/100 PY) versus 52/693 (7.5/100 PY); HR = 2.13; 95%-CI, 1.28-3.65, p = .002) with stroke rates 67% and 68% lower than anticipated by preprocedural CHADS₂ score. Combined safety endpoint (major periprocedural complications and major, life-threatening or fatal bleedings) occurred in 22/653 (3.4/100 PY) versus 28/693 (4.0/100 PY); HR = 1.20; 95%-CI, 0.66-2.20, p = .52).

CONCLUSIONS

Compared with patients at low risk of stroke, LAAC with Amplatzer devices is associated with similar safety and efficacy in high-risk patients in our study.

Septicemia and mortality after noncardiac surgery associated with CHA2DS2-VASc score: a retrospective cohort study based on a real-world database

Background

Little was know about the association between the CHA2DS2-VASc score and postoperative outcomes. Our purpose is to evaluate the effects of CHA2DS2-VASc score on the perioperative outcomes in patients with atrial fibrillation (AF).

Methods

We identified 47,402 patients with AF over the age of 20 years who underwent noncardiac surgeries between 2008 and 2013 from claims data of the National Health Insurance in Taiwan. The CHA2DS2-VASc score was used to evaluate postoperative complications, mortality and the consumption of medical resources by calculating adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Compared with patients with a CHA2DS2-VASc score of 0, patients with scores ≥ 5 had an increased risk of postoperative septicemia (OR 2.76, 95% CI 2.00–3.80), intensive care (OR 2.55, 95% CI 2.12–3.06), and mortality (OR 2.04, 95% CI 1.14–3.64). There was a significant positive correlation between risk of postoperative complication and the CHA2DS2-VASc score (P < 0.0001).

Conclusion

The CHA2DS2-VASc score was highly associated with postoperative septicemia, intensive care, and 30-day mortality among AF patients. Cardiologists and surgical care teams may consider using the CHA2DS2-VASc score to evaluate perioperative outcome risks in patients with AF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01209-z.

Perioperative Neurological Evaluation and Management to Lower the Risk of Acute Stroke in Patients Undergoing Noncardiac, Nonneurological Surgery: A Scientific Statement From the American Heart Association/American Stroke Association

Perioperative stroke is a potentially devastating complication in patients undergoing noncardiac, nonneurological surgery. This scientific statement summarizes established risk factors for perioperative stroke, preoperative and intraoperative strategies to mitigate the risk of stroke, suggestions for postoperative assessments, and treatment approaches for minimizing permanent neurological dysfunction in patients who experience a perioperative stroke. The first section focuses on preoperative optimization, including the role of preoperative carotid revascularization in patients with high-grade carotid stenosis and delaying surgery in patients with recent strokes. The second section reviews intraoperative strategies to reduce the risk of stroke, focusing on blood pressure control, perioperative goal-directed therapy, blood transfusion, and anesthetic technique. Finally, this statement presents strategies for the evaluation and treatment of patients with suspected postoperative strokes and, in particular, highlights the value of rapid recognition of strokes and the early use of intravenous thrombolysis and mechanical embolectomy in appropriate patients.

Underutilization of Perioperative Screening for Cardiovascular Events After Noncardiac Surgery in Alberta

BACKGROUND

Perioperative myocardial injury after noncardiac surgery affects more than 10% of individuals, with increased morbidity and mortality. Perioperative cardiac risk assessment targets the identification of this high-risk population using preoperative natriuretic peptides and postoperative troponin measurements. Our objective was to assess the use of these biomarkers in the province of Alberta.

METHODS

A retrospective cohort of all patients who underwent noncardiac surgery in Alberta from January 2013 to December 2017 was created using linked provincial administrative databases. Inclusion criteria were modified from recommendations for perioperative cardiac screening including: patients with a Revised Cardiac Risk Index score ≥ 1 and age 65 years or older, or 45 years of age or older with history of cardiovascular disease, with planned overnight hospital stay.

RESULTS

In our cohort of 59,506 patients, only 6.8% underwent preoperative natriuretic peptide screening. Rates of appropriate preoperative natriuretic peptide testing increased marginally from 5.7% to 8.8% over the study period. Postoperative troponin was measured at least once in 19.5% of patients. Patients with elevated perioperative screening biomarkers showed increased 6-month mortality, and increased hospitalizations for heart failure and acute coronary syndromes.

CONCLUSIONS

The use of biomarkers to assist in cardiac risk stratification and postoperative monitoring remains low. Addressing access to these tests and improving physician education regarding the asymptomatic nature of postoperative cardiac events might improve compliance with national guidelines.

Application of net reclassification index to non-nested and point-based risk prediction models: a review

Much of medical risk prediction involves externally derived prediction equations, nomograms, and point-based risk scores. These settings are vulnerable to misleading findings of incremental value based on versions of the net reclassification index (NRI) in common use. By applying non-nested models and point-based risk scores in the setting of stroke risk prediction in patients with atrial fibrillation (AF), we demonstrate current recommendations for presentation and interpretation of the NRI. We emphasize pitfalls that are likely to occur with point-based risk scores that are easy to neglect when statistical methodology is focused on continuous models. In order to make appropriate decisions about risk prediction and personalized medicine, physicians, researchers, and policy makers need to understand the strengths and limitations of the NRI.

Renal function and outcomes after catheter ablation of patients with atrial fibrillation: The Guangzhou atrial fibrillation ablation registry

INTRODUCTION

Chronic kidney disease (CKD) has been associated with incident atrial fibrillation (AF) and its complications, but data from Asian cohorts are limited.

AIM

To explore the relationship of AF recurrence after catheter ablation (CA) with eGFR as a continuous variable, and with different renal function categories (normal: estimated glomerular filtration rate [eGFR] ≥90mL/min/1.73 m²; mild CKD: eGFR 60-89mL/min/1.73 m²; moderate CKD: eGFR 45-59mL/min/1.73 m²; severe CKD: <45mL/min/1.73 m²), using data from the Guangzhou Atrial Fibrillation Ablation Registry.

METHODS

We studied consecutive symptomatic adult patients with non-valvular AF, refractory to at least one antiarrhythmic drug and eligible for CA, in Guangdong General Hospital between June 2011 and August 2015.

RESULTS

Data were available from 1407 consecutive patients (mean age 57.3±11.5 years; 68% men) with non-valvular AF undergoing radiofrequency or cryoballoon ablation. During a mean follow-up of 20.7±8.8 months, 18.6% of patients with paroxysmal AF and 50.5% with non-paroxysmal AF had AF recurrence. On multivariable analysis, eGFR (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.96-0.97) was an independent risk factor for AF recurrence, with a good predictive value (area under the curve 0.74, 95% CI 0.72-0.77; P<0.01). In the normal renal function, and mild, moderate and severe CKD categories, AF recurrence rates were 11.5%, 29.3%, 72.0% and 93.3%, respectively. Compared with normal renal function, there were stepwise increased risks of AF recurrence with mild CKD (HR 3.30, 95% CI 2.55-4.26; P<0.01), moderate CKD (HR 9.43, 95% CI 6.76-13.16; P<0.01) and severe CKD (HR 12.35, 95% CI 6.93-21.99; P<0.01).

CONCLUSIONS

In a large cohort of Asian patients with AF, renal dysfunction increased the risk of AF recurrence after CA. AF recurrence gradually increased with worsening kidney function in this cohort.

[Management of hemorrhage in patients treated with direct oral anticoagulants]

The introduction of nonvitamin K antagonistic, direct oral anticoagulants (DOAC) made thromboembolic prophylaxis easier for patients. For many physicians, however, there is still uncertainty about monitoring, preoperative discontinuation, and restarting of DOAC therapy. Guidelines for the management of bleeding are provided, but require specific therapeutic skills in the management of diagnostics and therapy of acute hemorrhage. Small clinical studies and case reports indicate that unspecific therapy with prothrombin complex concentrates (PCC) and activated PCC (aPCC) concentrate may reverse DOAC-induced anticoagulation. However, PCC or aPCC at higher doses potentially provoke thromboembolic complications. However, idarucizumab, a specific, fast-acting, antidote for dabigatran, provides immediate and sustained reversal with no intrinsic or prohemostatic activity. This review article provides an overview of the pharmacology and potential risk of DOAC and the management in the perioperative period with a focus of current concepts in the treatment of DOAC-associated bleeding.

Clinical utility of the revised cardiac risk index in older Chinese patients with known coronary artery disease

Objectives

The revised Cardiac Risk Index (RCRI) is the most widely used risk prediction tool for postoperative cardiac adverse events. We aim to explore the predictive ability of the RCRI in older Chinese patients with coronary artery disease (CAD) undergoing noncardiac surgery, which has not been previously evaluated.

Methods

We performed a multicenter, prospective study. We enrolled a total of 1,202 patients, aged >60 years, with a history of CAD who underwent noncardiac surgery. Perioperative data were extracted from an electronic database. The primary end point was defined as an occurrence of a postoperative major cardiac event (PoMCE) within 30 days. Logistic regression analysis was performed to evaluate the performance of the RCRI. A modified RCRI was created and compared with the original RCRI with regard to its ability to predict postoperative cardiac events.

Results

Of the enrolled patients, 4.3% experienced PoMCE. Most components of the RCRI were not predictive of postoperative cardiac events with the exception of insulin-dependent diabetes mellitus (odds ratio =2.38, 95% CI: 1.11-5.11; P=0.03). The RCRI performed no better than chance (area under the curve =0.53; 95% CI: 0.45-0.61) in identifying patients' cardiac risk. The modified score had a higher discriminatory ability toward PoMCE (c index, 0.69 versus 0.53; P<0.01).

Conclusion

The original RCRI shows poor predictive ability in Chinese patients with CAD undergoing noncardiac surgery.

Temporal variability of readmission determinants in postoperative vascular surgery patients

Introduction:

Clinical information continues to be limited regarding changes in the temporal risk profile for readmissions during the initial postoperative year in vascular surgery patients. We set out to describe the associations between demographics, clinical outcomes, comorbidity indices, and hospital readmissions in a sample of patients undergoing common extremity revascularization or dialysis access (ERDA) procedures. We hypothesized that factors independently associated with readmission will evolve from “short-term” to “long-term” determinants at 30-, 180-, and 360-day postoperative cutoff points.

Methods:

Following IRB approval, medical records of patients who underwent ERDA at two institutions were retrospectively reviewed between 2008 and 2014. Abstracted data included patient demographics, procedural characteristics, the American Society of Anesthesiologists score, Goldman Criteria for perioperative cardiac assessment, the Charlson comorbidity index, morbidity, mortality, and readmission (at 30-, 180-, and 360-days). Univariate analyses were performed for readmissions at each specified time point. Variables reaching statistical significance of P < 0.20 were included in multivariate analyses for factors independently associated with readmission.

Results:

A total of 450 of 744 patients who underwent ERDA with complete medical records were included. Patients underwent either an extremity revascularization (e.g. bypass or endarterectomy, 406/450) or a noncatheter dialysis access procedure (44/450). Sample characteristics included 262 (58.2%) females, mean age 61.4 ± 12.9 years, 63 (14%) emergent procedures, and median operative time 164 min. Median hospital length of stay (index admission) was 4 days. Cumulative readmission rates at 30-, 180-, and 360-day were 12%, 27%, and 35%, respectively. Corresponding mortality rates were 3%, 7%, and 9%. Key factors independently associated with 30-, 180-, and 360-day readmissions evolved over the study period from comorbidity and morbidity-related issues in the short-term to cardiovascular and graft patency issues in the long-term. Any earlier readmission elevated the risk of subsequent readmission.

Conclusions:

We noted important patterns in the temporal behavior of hospital readmission risk in patients undergoing ERDA. Although factors independently associated with readmission were not surprising (e.g. comorbidity profile, cardiovascular status, and graft patency), the knowledge of temporal trends described in this study may help determine clinical risk profiles for individual patients and guide readmission reduction strategies. These considerations will be increasingly important in the evolving paradigm of value-based healthcare.

The prediction of postoperative stroke or death in patients with preoperative atrial fibrillation undergoing non-cardiac surgery: a VISION sub-study

BACKGROUND

The optimal means of pre-operative risk stratification in patients with atrial fibrillation (AF) is uncertain.

OBJECTIVE

To examine the accuracy of AF thromboembolic risk models (the CHADS2, CHA2DS2-VASc, and R2CHADS2 scores) for predicting 30-day stroke and/or all-cause mortality after non-cardiac surgery in patients with preoperative AF, and to compare these risk scores with the Revised Cardiac Risk Index (RCRI).

PATIENTS/METHODS

A multicentre (8 countries, 2007-2011) prospective cohort study of patients ≥ 45 years of age undergoing inpatient non-cardiac surgery, who were followed until 30 days after surgery. We calculated c-statistics for each risk prediction model and net reclassification improvements (NRIs) compared with the RCRI.

RESULTS

The 961 patients with preoperative AF were at higher risk of any cardiovascular event in the 30 days postoperatively compared with the 13 001 patients without AF: 26.6% vs. 9.0%; adjusted odds ratio, 1.58; 95% confidence interval [CI], 1.33-1.88. All thromboembolic risk scores predicted postoperative death just as well as the RCRI (with c-indices between 0.67 and 0.72). Compared with the RCRI (which had a c-index of 0.64 for 30-day stroke/death), the CHADS2 (c-index, 0.67; NRI, 0.31; 95% CI, 0.02-0.61) significantly improved postoperative stroke/mortality risk prediction, largely due to improved discrimination of patients who did not subsequently have an event.

CONCLUSIONS

In AF patients, the three thromboembolic risk scores performed similarly to the RCRI in predicting death within 30 days and the CHADS2 score was the best predictor of postoperative stroke/death regardless of type of surgery.

Coagulopathy and Anticoagulation During Thoracic Surgery

Coagulopathy and bleeding in thoracic surgery may be compounded by the chronic use of anticoagulants and antiplatelet agents. Timely preoperative cessation and postoperative resumption of these antithrombotic drugs are critical in reducing the risks of perioperative major bleeding and thromboembolism. This article describes the various strategies for the optimal perioperative management of antithrombotics based on individual assessment of each patient and the most recent multisociety guidelines.

Variation in critical care unit admission rates and outcomes for patients with acute coronary syndromes or heart failure among high- and low-volume cardiac hospitals

Background

Little is known about cross‐hospital differences in critical care units admission rates and related resource utilization and outcomes among patients hospitalized with acute coronary syndromes (ACS) or heart failure (HF).

Methods and Results

Using a population‐based sample of 16 078 patients admitted to a critical care unit with a primary diagnosis of ACS (n=14 610) or HF (n=1467) between April 1, 2003 and March 31, 2013 in Alberta, Canada, we stratified hospitals into high (>250), medium (200 to 250), or low (<200) volume based on their annual volume of all ACS and HF hospitalization. The percentage of hospitalized patients admitted to critical care units varied across low, medium, and high‐volume hospitals for both ACS and HF as follows: 77.9%, 81.3%, and 76.3% (P<0.001), and 18.0%, 16.3%, and 13.0% (P<0.001), respectively. Compared to low‐volume units, critical care patients with ACS and HF admitted to high‐volume hospitals had shorter mean critical care stays (56.6 versus 95.6 hours, P<0.001), more critical care procedures (1.9 versus 1.2 per patient, <0.001), and higher resource‐intensive weighting (2.8 versus 1.5, P<0.001). No differences in in‐hospital mortality (5.5% versus 6.2%, adjusted odds ratio 0.93; 95% CI, 0.61 to 1.41) were observed between high‐ and low‐volume hospitals; however, 30‐day cardiovascular readmissions (4.6% versus 6.8%, odds ratio 0.77; 95% CI, 0.60 to 0.99) and cardiovascular emergency‐room visits (6.6% versus 9.5%, odds ratio 0.80; 95% CI, 0.69 to 0.94) were lower in high‐volume compared to low‐volume hospitals. Outcomes stratified by ACS or HF admission diagnosis were similar.

Conclusions

Cardiac patients hospitalized in low‐volume hospitals were more frequently admitted to critical care units and had longer hospitals stays despite lower resource‐intensive weighting. These findings may provide opportunities to standardize critical care utilization for ACS and HF patients across high‐ and low‐volume hospitals.