Preoperative atrial fibrillation is an independent predictor of worse early and late outcomes after isolated coronary artery bypass graft surgery

Prognostic factors of 10-year mortality after coronary artery bypass graft surgery: a secondary analysis of the arterial revascularization trial

OBJECTIVES

The objective of this investigation was to determine the preoperative prognostic factors of long-term (10-year) mortality in patients treated with isolated coronary artery bypass graft surgery in the arterial revascularization trial (ART).

METHODS

A post hoc analysis of the ART was conducted. Cumulative 10-year mortality was estimated using the Kaplan-Meier method. Prospectively collected preoperative data were used to determine the prognostic factors of 10-year all-cause mortality in patients who participated in the ART (Cox proportional hazards model).

RESULTS

A total of 3102 patients who participated in the ART were included in the analysis. Ten-year follow-up was completed in 3040 patients (98%). A total of 644 patients (20.8%) had died by 10 years. Preoperative factors that were identified as statistically significant predictors of 10-year mortality in the multivariable analysis (all P ≤ 0.01) were: left ventricular ejection fraction, atrial fibrillation, age, diabetes, prior cerebrovascular event (stroke or transient ischaemic attack), serum creatinine and smoking status. The following variables were significantly associated in univariable models but did not retain significance in the multivariable model for mortality: non-Caucasian ethnicity, hypertension, peripheral vascular disease, chronic obstructive pulmonary disease and prior myocardial infarction.

CONCLUSIONS

Independent predictors of 10-year mortality in the ART were multifactorial. Several key independent predictors of 10-year mortality in the ART were identified including: heart function, renal function, cerebrovascular disease, age, atrial fibrillation, smoking status and diabetes. Understanding which preoperative variables influence long-term outcome after coronary artery bypass grafting may help to target treatments to those at higher risk to reduce mortality.

Temporal trends and predictors of surgical ablation for atrial fibrillation across a multistate healthcare system

Background

Multiple class I and class IIa recommendations exist related to surgical ablation (SA) of atrial fibrillation (AF) in patients undergoing cardiac surgery.

Objective

Examine temporal trends and predictors of SA for AF in a large US healthcare system.

Methods

We retrospectively analyzed data from the Society for Thoracic Surgery (STS) Adult Cardiac Surgery Database for 21 hospitals in the Providence St. Joseph Health system. All patients with preoperative AF who underwent isolated coronary artery bypass graft (CABG) surgery, isolated aortic valve replacement (AVR), AVR with CABG surgery (AVR+CABG), isolated mitral valve repair or replacement (MVRr), and MVRr with CABG surgery (MVRr+CABG) from July 1, 2014, to March 31, 2020 were included. Temporal trends in SA were evaluated using the Cochran-Armitage trends test. A multilevel logistic regression model was used to examine patient-, hospital-, and surgeon-level predictors of SA.

Results

Among 3124 patients with preoperative AF, 910 (29.1%) underwent SA. This was performed most often in those undergoing isolated MVRr (n = 324, 44.8%) or MVRr+CABG (n = 75, 35.2%). Rates of SA increased over time and were highly variable between hospitals. Years since graduation from medical school for the primary operator was one of the few predictors of SA: odds ratio (95% confidence interval) = 0.71 (0.56–0.90) for every 10-year increase. Annual surgical (both hospital and operator) and AF catheter ablation volumes were not predictive of SA.

Conclusion

Wide variability in rates of SA for AF exist, underscoring the need for greater preoperative collaboration between cardiologists, electrophysiologists, and cardiac surgeons.

Improved outcomes in CABG patients with atrial fibrillation associated with surgical left atrial appendage exclusion

BACKGROUND

We sought to determine the impact of left atrial appendage clip exclusion (LAACE) on coronary artery bypass grafting (CABG) outcomes among patients with pre-existing atrial fibrillation (AF).

METHODS

From October 1, 2015 to October 1, 2017, 4210 Medicare beneficiaries with pre-existing AF underwent isolated CABG (i.e., without ablation) with (n = 931) or without (n = 3279) LAACE. Inverse probability of treatment weighting was used to evaluate the effect of concomitant LAACE on short- and long-term outcomes after CABG. Long term risks of thromboembolism and mortality were assessed using competing-risk regression and Cox proportional hazard models.

RESULTS

Operative mortality, length of stay, and 30-day readmission did not differ between groups. Thromboembolism risk was 26% lower for the CABG + LAACE group compared with isolated CABG over a 2-year time-to-event analysis (sub hazard ratio [sHR] 0.74, 95% confidence interval [CI] 0.54-1.00, p = .049). There were no differences in ischemic stroke rates. All-cause mortality risk was 45% lower for CABG + LAACE during the late follow-up period (91-730 days; HR 0.55, 95% CI 0.32-0.95, p = .031). The late period annual absolute all-cause mortality rate was 3.7% for CABG + LAACE and 6.9% for isolated CABG. There were lower readmission rates (31% vs. 43%, p < .001) and total inpatient days (4.0 days vs. 7.2 days, p < .01.) for the CABG + LAACE during follow-up. Total hospital in and out-patient treatment costs were similar between groups through one year.

CONCLUSIONS

Concomitant LAA exclusion via an epicardial closure device is associated with reduced CABG mortality, thromboembolic events, and readmissions in patients with pre-existing atrial fibrillation.

Preoperative atrial fibrillation in association with reduced haemoglobin predicts increased 30-d mortality after cardiac surgery

OBJECTIVES

Atrial fibrillation is the most common arrhythmia occurring after cardiac surgery. Less attention has been focused on preoperative atrial fibrillation and anaemia as risk factors for mortality after cardiac surgery. The aim of this study was to determine preoperative risk factors for 30-d mortality after open-heart surgery. Design. The study population consisted of 2015 patients (73.4% men; mean age 68 years) undergoing coronary artery bypass grafting (CABG) (52.0%), aortic valve replacement (AVR) (18.6%), AVR and CABG (10.0%), mitral valve plasty or replacement (14.0%), and AVR and aortic root reconstruction (ARR) (5.5%) in Kuopio University Hospital from January 2013 to December 2016. Univariate and multivariate Cox proportional hazards models were used for statistical analyses. Kaplan-Meier survival curves were generated. Results. Total 30-d mortality was 1.8%. By Cox regression analysis, predictors of 30-d mortality (hazard ratio [HR] [95% confidence interval [CI]]) included female gender (1.95 [1.00-3.77]), preoperative atrial fibrillation, (2.38 [1.12-5.03]) reduced haemoglobin level (3.40 [1.47-7.90]), and pulmonary congestion (3.16 [1.52-6.55]). The combination of preoperative reduced haemoglobin and preoperative atrial fibrillation was a strong predictor (12.37 [4.40-34.77], p < .001). Estimated glomerular filtration rate (eGFR) predicted 30-d mortality in univariate models but was not an independent predictor in multivariate models. Conclusions. According to the main findings of our study, the combination of preoperative atrial fibrillation and reduced haemoglobin level substantially increase the risk of 30-d mortality after cardiac surgery. Identification of high-risk patients pre-operatively could help to make optimal clinical decisions for timing of operation and perioperative treatment.

Teaching an Old Dog New Tricks: Colchicine in Cardiovascular Medicine

Colchicine is one of the oldest known drugs that remains part of the current pharmacopeia. Recent studies have examined the efficacy of colchicine in cardiology with promising results. We conducted a search of electronic databases for studies on colchicine in cardiovascular medicine published through October 2016. As the utilization of colchicine in the management of cardiac conditions grows, it is paramount that internists and cardiologists are familiarized with its benefits and risks. We present a comprehensive review of the role of colchicine in the management of cardiovascular diseases with a strong emphasis on side effects and potential drug interactions.

Efficacy of β-blocker therapy for secondary prevention for patients undergoing coronary artery bypass grafting surgery

PURPOSE OF REVIEW

The efficacy and safety of β-blockers in the treatment of cardiovascular diseases, such as ischemic heart disease, cardiac arrhythmias, and heart failure, have been well established for decades. In this article, we review the current opinions on the application of β-blockers for secondary prevention in patients undergoing coronary artery bypass grafting (CABG) surgery.

RECENT FINDINGS

As the average age of patients treated surgically for coronary artery disease (CAD) is increasing, it is not uncommon to have candidates for CABG presenting with concomitant atrial fibrillation, heart failure or hypertension, most of which were caused by excessive activation of the adrenergic nervous system. In a recent decade, a number of national quality-improvement efforts using a variety of techniques have been made to increase the use of β-blocker therapy before or following the CABG. Results from recent large observational studies among patients with CAD showed that β-blockers were associated with a lower risk of cardiac events only among those with heart failure or recent myocardial infarction. However, the consistent use of β-blockers could benefit those with or without prior myocardial infarction who underwent CABG and discharged alive.

SUMMARY

In real-world clinical practice, β-blockers are effective and safe to control heart rate and symptoms in patients with CAD, especially for those concomitant with left ventricular systolic dysfunction or prior myocardial infarction. Current evidence supports the preoperative use of β-blocker therapy for patients undergoing CABG as a prevention of new-onset atrial fibrillation. It is reasonable to continue β-blockers as chronic therapy in all CABG patients without contraindications after hospital discharge. Further strategies should be developed to understand and improve discharge prescription of β-blockers and long-term patient adherence.

Effects of five preoperative cardiovascular drugs on mortality after coronary artery bypass surgery: A retrospective analysis of an observational study of 16, 192 patients

BACKGROUND

Statins reduce risk from coronary artery bypass graft (CABG) surgery, but the influence of angiotensin-converting enzyme inhibitors, alpha-2 adrenergic agonists, calcium channel blockers and beta-blockers is less clear.

OBJECTIVES

We investigated the association of each of these drugs with perioperative risk, accounting for different confounders, and evaluated the class, dose-response and long-term protective effect of statins.

DESIGN

A retrospective analysis of observational data.

SETTING

United Kingdom.

PATIENTS

Sixteen thousand one hundred and ninety-two patients who underwent CABG surgery during the period 01 January 2004 to 31 December 2013 and contributed data to Primary Care Clinical Practice Research Datalink.

EXPOSURE VARIABLES

Cardiovascular drugs.

OUTCOME MEASURE

Perioperative mortality within 30 days of surgery.

STATISTICAL ANALYSIS

Five multivariable logistic regression models and a further Cox regression model were used to account for preexisting cardiovascular and other comorbidities along with lifestyle factors such as BMI, smoking and alcohol use.

RESULTS

Exposure to statins was most prevalent (85.1% of patients), followed by beta-blockers (72.8%), angiotensin-converting enzyme inhibitors (60.5%), calcium channel blockers (42.8%) and alpha-2 adrenergic agonists (1.2%). The mortality rate was 0.8% in patients not prescribed statins and 0.4% in those on statins. Statins were associated with a statistically significant reduced perioperative mortality in all five logistic regression models with adjusted odds ratios (OR) (95% confidence interval, 95% CI) ranging from 0.26 (0.13 to 0.54) to 0.35 (0.18 to 0.67). Cox regression for perioperative mortality [adjusted hazard ratio (95% CI) 0.40 (0.20 to 0.80)] and 6-month mortality [adjusted hazard ratio (95% CI) 0.63 (0.42 to 0.92)] produced similar results. Of the statin doses tested, only simvastatin 40 mg exerted protective effects. The other cardiovascular drugs lacked consistent effects across models.

CONCLUSION

Statins appear consistently protective against perioperative mortality from CABG surgery in multiple models, an effect not shared by the other cardiovascular drugs. Further data are needed on whether statins exert class and dose-response effects.