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Janak Mehta Award This article is accompanied by an invited commentary by Dr. Praveen
Kerala Varma
Prediction of postoperative atrial fibrillation after coronary artery bypass grafting surgery: Is CHA2DS2-VASc score useful? Deepak Borde, Uday Gandhe, Neha Hargave, Kaushal Pandey1, Manish Mathew1, Shreedhar Joshi2 Departments of Cardiac Anaesthesia and 1Cardiac Surgery, P. D. Hinduja National Hospital, Lilavati Hospital, Fortis Hospital, Mumbai, 2Department of Cardiac Anaesthesia, Sri Jayadeva Institute of Cardiovascular Sciences and Research Institute, Bengaluru, Karnataka, India
ABSTRACT
Received: 09-12-13 Accepted: 28-04-14
Aims and Objectives: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass grafting (CABG) surgery. The identification of patients at risk for POAF would be helpful to guide prophylactic therapy. Presently, there is no simple preoperative scoring system available to predict patients at higher risk of POAF. In a retrospective observational study, we evaluated the usefulness of CHA2DS2-VASc score to predict POAF after CABG. Materials and Methods: After obtaining approval from Institutional Review Board, 729 patients undergoing CABG on cardiopulmonary bypass (CPB) were enrolled. Patients were followed in the postoperative period for POAF. A multiple regression analysis was run to predict POAF from various variables. The area under the receiver operating characteristic (ROC) curve was calculated to test discriminatory power of CHA2DS2-VASc score to predict POAF. Results: POAF occurred in 95 (13%) patients. The patients with POAF had higher CHA2DS2-VASc scores than those without POAF (4.09 ± 0.90 vs. 2.31 ± 1.21; P < 0.001). The POAF rates after cardiac surgery increased with increasing CHA2DS2-VASc scores. The odds ratio for predicting POAF was highest with higher CHA2DS2-VASc scores (3.68). When ROC curve was calculated for the CHA2DS2-VASc scores, area of 0.87 was obtained, which was statistically significant (P < 0.0001). Conclusions: The CHA2DS2-VASc score was found useful in predicting POAF after CABG. This scoring system is simple and convenient to use in the preoperative period to alert the clinician about higher probability of POAF after CABG surgery. Key words: Cardiopulmonary bypass; CHA2DS2-VASc score; Coronary artery bypass grafting; Postoperative atrial fibrillation
INTRODUCTION
Access this article online
Website: www.annals.in PMID: *** DOI: 10.4103/0971-9784.135841 Quick Response Code:
Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass grafting (CABG) surgery.[1,2] Patients with POAF tend to have longer hospital stay, increased perioperative morbidity and greater early and long-term mortality.[2-5] Although prophylaxis with antiarrhythmic drugs can decrease the incidence of POAF; however, such an approach in all patients is not cost-effective and may even have adverse effects. [2] At present, there is no simple preoperative scoring system available to predict patients at higher risk of POAF. The identification of patients at
risk for POAF would be helpful. CHA2DS2-VASc score is recommended to guide antithrombotic therapy in patients with AF or atrial futter.[6,7] All the components of this score are known to be associated with increased incidence of POAF. There is recent interest in this scoring system to predict POAF.[8,9] Therefore, we tested the hypothesis that CHA2DS2-VASc score is useful to predict POAF after CABG surgery. MATERIALS AND METHODS This is a retrospective observational study of patients who had undergone CABG on CPB with or without valve replacement or
Address for correspondence: Dr. Deepak Borde, Department of Cardiac Anesthesia, P. D. Hinduja National Hospital, Veert Sawarkar Marg, Mahim, Mumbai - 400 022, Maharashtra, India. E-mail: [email protected]
182
Annals of Cardiac Anaesthesia z Vol. 17:3 z Jul-Sep-2014
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repair surgery, operated by a single surgical team from January 2012 to June 2013. The Institutional Review Board approved the study with waiver of consent. A total of 789 patients underwent surgery during this period and were considered eligible for inclusion in the study. Fifty-one patients were excluded because of various reasons such as incomplete or nonavailability of medical records, preoperative history of AF, and preoperative use of pacemaker and antiarrhythmic drugs. Another nine patients were excluded because antiarrhythmic medications were administered for ventricular arrhythmias in early postoperative period. The final analysis included 729 patients. Demographic and procedural data abstracted from medical records included medical history, clinical examination, investigations and use of preoperative medication (β-blockers, angiotensin converting enzyme inhibitor [ACEI]/angiotensin receptor blockers [ARB], and statins), details of cardiopulmonary bypass [CPB], aortic cross clamp time, number of grafts, use of inotropes and blood transfusion in perioperative period.The CHA2DS2-VASc scores were calculated for each patient[6] [Table 1]. In addition, data on the principal outcome, new onset POAF defined as new electrocardiography evidence of AF requiring treatment was determined, including its timing and treatment. General anesthesia was induced with midazolam, fentanyl and etomidate. Rocuronium was used as a muscle relaxant. After induction, intravenous methyl prednisone 500 mg bolus was given to all patients. Anesthesia was maintained by titrated doses of sevoflurane, infusion of fentanyl and midazolam. All patients were operated through median sternotomy. CPB was established with aortocaval cannulation after adequate heparinization (activated clotting time >400 s). Normothermia (35-37°C) was maintained throughout the surgery. Extracorporeal circuit consisted of membrane oxygenator, roller pump, tubings and Table 1: The definitions of acronym CHA2DS2-VASc Risk factor
Score
Congestive cardiac failure/LV dysfunction
1
Hypertension
1
Age ≥75 years
2
Diabetes mellitus
1
Stroke/transient ischemic attack/thromboembolism
2
Vascular disease (prior MI/carotid or peripheral vascular arterial disease)
1
Age 65-74 years
1
Sex category (female)
1
Total score LV: Left ventricle, MI: Myocardial infarction
Annals of Cardiac Anaesthesia z Vol. 17:3 z Jul-Sep-2014
crystalloid prime solution. Warm blood cardioplegia was used to achieve cardiac arrest and to provide myocardial protection during aortic clamp. After completion of the distal anastomoses the aortic clamp was released, and proximal anastomoses were completed with a partial side-clamp on the aorta. The preoperative medications like β-blockers, ACEI/ARBs, statins were re-started in the early postoperative period unless medically contraindicated. Statistical analysis Continuous variables are described as means with standard deviations and are compared between groups by using Student’s t-test (parametric data) or Mann-Whitney U-test (nonparametric data). Dichotomous variables were presented as percentages and compared between groups by Chi-square test or Fisher exact test. For primary analysis all demographic, surgical, and medication utilization variables with a P ≤ 0.2 in univariate analysis were entered into a stepwise forward multivariate logistic regression model with POAF as the binary dependent outcome. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for all independent variables retained in the multivariate logistic regression model with P ≤ 0.05 was considered as significant. The area under the receiver operating characteristic (ROC) curve was calculated to test discriminatory power of CHA2DS2-VASc score to predict POAF. RESULTS Baseline clinical characteristics of patients with and without POAF are summarized in Table 2. Of the 729 study patients, 95 (13%) had POAF after CABG. The patients with POAF were older and had a significantly higher prevalence of hypertension, diabetes mellitus (P < 0.0001) and vascular disease (peripheral and carotid artery disease; P = 0.0005) compared to patients without POAF. The patients with POAF had significantly higher rates of blood or blood product transfusion and inotrope use in the perioperative period (P < 0.0001). The first choice of inotrope was adrenaline (58% of total 230 patients in which inotropes were used) followed by dopamine/noradrenaline. Combined inotrope therapy was used in 20% of patients. The patients with POAF had higher CHA2DS2-VASc scores than those without POAF (4.09 ± 0.90 vs. 2.31 ± 1.21; P < 0.0001). A multiple regression was run to predict POAF from various variables. CHA 2DS 2-VASc score, ejection fraction, peripheral vascular disease (PVD), statin use, 183
[Downloaded free from http://www.annals.in on Saturday, July 05, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Borde, et al.: CHA2DS2-VASc score to predict POAF
Table 2: Patient demographics, surgical characteristics, and medication use Total (n=729)
POAF (n=95)
No POAF (n=634)
P value
Age (years)
61.17±8.26
65.24±8.11
60.57±8.15
Janak Mehta Award This article is accompanied by an invited commentary by Dr. Praveen
Kerala Varma
Prediction of postoperative atrial fibrillation after coronary artery bypass grafting surgery: Is CHA2DS2-VASc score useful? Deepak Borde, Uday Gandhe, Neha Hargave, Kaushal Pandey1, Manish Mathew1, Shreedhar Joshi2 Departments of Cardiac Anaesthesia and 1Cardiac Surgery, P. D. Hinduja National Hospital, Lilavati Hospital, Fortis Hospital, Mumbai, 2Department of Cardiac Anaesthesia, Sri Jayadeva Institute of Cardiovascular Sciences and Research Institute, Bengaluru, Karnataka, India
ABSTRACT
Received: 09-12-13 Accepted: 28-04-14
Aims and Objectives: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass grafting (CABG) surgery. The identification of patients at risk for POAF would be helpful to guide prophylactic therapy. Presently, there is no simple preoperative scoring system available to predict patients at higher risk of POAF. In a retrospective observational study, we evaluated the usefulness of CHA2DS2-VASc score to predict POAF after CABG. Materials and Methods: After obtaining approval from Institutional Review Board, 729 patients undergoing CABG on cardiopulmonary bypass (CPB) were enrolled. Patients were followed in the postoperative period for POAF. A multiple regression analysis was run to predict POAF from various variables. The area under the receiver operating characteristic (ROC) curve was calculated to test discriminatory power of CHA2DS2-VASc score to predict POAF. Results: POAF occurred in 95 (13%) patients. The patients with POAF had higher CHA2DS2-VASc scores than those without POAF (4.09 ± 0.90 vs. 2.31 ± 1.21; P < 0.001). The POAF rates after cardiac surgery increased with increasing CHA2DS2-VASc scores. The odds ratio for predicting POAF was highest with higher CHA2DS2-VASc scores (3.68). When ROC curve was calculated for the CHA2DS2-VASc scores, area of 0.87 was obtained, which was statistically significant (P < 0.0001). Conclusions: The CHA2DS2-VASc score was found useful in predicting POAF after CABG. This scoring system is simple and convenient to use in the preoperative period to alert the clinician about higher probability of POAF after CABG surgery. Key words: Cardiopulmonary bypass; CHA2DS2-VASc score; Coronary artery bypass grafting; Postoperative atrial fibrillation
INTRODUCTION
Access this article online
Website: www.annals.in PMID: *** DOI: 10.4103/0971-9784.135841 Quick Response Code:
Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass grafting (CABG) surgery.[1,2] Patients with POAF tend to have longer hospital stay, increased perioperative morbidity and greater early and long-term mortality.[2-5] Although prophylaxis with antiarrhythmic drugs can decrease the incidence of POAF; however, such an approach in all patients is not cost-effective and may even have adverse effects. [2] At present, there is no simple preoperative scoring system available to predict patients at higher risk of POAF. The identification of patients at
risk for POAF would be helpful. CHA2DS2-VASc score is recommended to guide antithrombotic therapy in patients with AF or atrial futter.[6,7] All the components of this score are known to be associated with increased incidence of POAF. There is recent interest in this scoring system to predict POAF.[8,9] Therefore, we tested the hypothesis that CHA2DS2-VASc score is useful to predict POAF after CABG surgery. MATERIALS AND METHODS This is a retrospective observational study of patients who had undergone CABG on CPB with or without valve replacement or
Address for correspondence: Dr. Deepak Borde, Department of Cardiac Anesthesia, P. D. Hinduja National Hospital, Veert Sawarkar Marg, Mahim, Mumbai - 400 022, Maharashtra, India. E-mail: [email protected]
182
Annals of Cardiac Anaesthesia z Vol. 17:3 z Jul-Sep-2014
[Downloaded free from http://www.annals.in on Saturday, July 05, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Borde, et al.: CHA2DS2-VASc score to predict POAF
repair surgery, operated by a single surgical team from January 2012 to June 2013. The Institutional Review Board approved the study with waiver of consent. A total of 789 patients underwent surgery during this period and were considered eligible for inclusion in the study. Fifty-one patients were excluded because of various reasons such as incomplete or nonavailability of medical records, preoperative history of AF, and preoperative use of pacemaker and antiarrhythmic drugs. Another nine patients were excluded because antiarrhythmic medications were administered for ventricular arrhythmias in early postoperative period. The final analysis included 729 patients. Demographic and procedural data abstracted from medical records included medical history, clinical examination, investigations and use of preoperative medication (β-blockers, angiotensin converting enzyme inhibitor [ACEI]/angiotensin receptor blockers [ARB], and statins), details of cardiopulmonary bypass [CPB], aortic cross clamp time, number of grafts, use of inotropes and blood transfusion in perioperative period.The CHA2DS2-VASc scores were calculated for each patient[6] [Table 1]. In addition, data on the principal outcome, new onset POAF defined as new electrocardiography evidence of AF requiring treatment was determined, including its timing and treatment. General anesthesia was induced with midazolam, fentanyl and etomidate. Rocuronium was used as a muscle relaxant. After induction, intravenous methyl prednisone 500 mg bolus was given to all patients. Anesthesia was maintained by titrated doses of sevoflurane, infusion of fentanyl and midazolam. All patients were operated through median sternotomy. CPB was established with aortocaval cannulation after adequate heparinization (activated clotting time >400 s). Normothermia (35-37°C) was maintained throughout the surgery. Extracorporeal circuit consisted of membrane oxygenator, roller pump, tubings and Table 1: The definitions of acronym CHA2DS2-VASc Risk factor
Score
Congestive cardiac failure/LV dysfunction
1
Hypertension
1
Age ≥75 years
2
Diabetes mellitus
1
Stroke/transient ischemic attack/thromboembolism
2
Vascular disease (prior MI/carotid or peripheral vascular arterial disease)
1
Age 65-74 years
1
Sex category (female)
1
Total score LV: Left ventricle, MI: Myocardial infarction
Annals of Cardiac Anaesthesia z Vol. 17:3 z Jul-Sep-2014
crystalloid prime solution. Warm blood cardioplegia was used to achieve cardiac arrest and to provide myocardial protection during aortic clamp. After completion of the distal anastomoses the aortic clamp was released, and proximal anastomoses were completed with a partial side-clamp on the aorta. The preoperative medications like β-blockers, ACEI/ARBs, statins were re-started in the early postoperative period unless medically contraindicated. Statistical analysis Continuous variables are described as means with standard deviations and are compared between groups by using Student’s t-test (parametric data) or Mann-Whitney U-test (nonparametric data). Dichotomous variables were presented as percentages and compared between groups by Chi-square test or Fisher exact test. For primary analysis all demographic, surgical, and medication utilization variables with a P ≤ 0.2 in univariate analysis were entered into a stepwise forward multivariate logistic regression model with POAF as the binary dependent outcome. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for all independent variables retained in the multivariate logistic regression model with P ≤ 0.05 was considered as significant. The area under the receiver operating characteristic (ROC) curve was calculated to test discriminatory power of CHA2DS2-VASc score to predict POAF. RESULTS Baseline clinical characteristics of patients with and without POAF are summarized in Table 2. Of the 729 study patients, 95 (13%) had POAF after CABG. The patients with POAF were older and had a significantly higher prevalence of hypertension, diabetes mellitus (P < 0.0001) and vascular disease (peripheral and carotid artery disease; P = 0.0005) compared to patients without POAF. The patients with POAF had significantly higher rates of blood or blood product transfusion and inotrope use in the perioperative period (P < 0.0001). The first choice of inotrope was adrenaline (58% of total 230 patients in which inotropes were used) followed by dopamine/noradrenaline. Combined inotrope therapy was used in 20% of patients. The patients with POAF had higher CHA2DS2-VASc scores than those without POAF (4.09 ± 0.90 vs. 2.31 ± 1.21; P < 0.0001). A multiple regression was run to predict POAF from various variables. CHA 2DS 2-VASc score, ejection fraction, peripheral vascular disease (PVD), statin use, 183
[Downloaded free from http://www.annals.in on Saturday, July 05, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Borde, et al.: CHA2DS2-VASc score to predict POAF
Table 2: Patient demographics, surgical characteristics, and medication use Total (n=729)
POAF (n=95)
No POAF (n=634)
P value
Age (years)
61.17±8.26
65.24±8.11
60.57±8.15
