Usefulness of the CHA2DS2VASc Score to Predict Postoperative Stroke in Patients Having Cardiac Surgery Independent of Atrial Fibrillation Julio G. Peguero, MDa, Omar Issa, DOb, Carlos Podesta, MDb, Hany M. Elmahdy, MDb, Orlando Santana, MDa,*, and Gervasio A. Lamas, MDa Despite its association with cardioembolic stroke, atrial fibrillation (AF) appears to be inconsistent as a risk factor for postoperative strokes in patients who underwent cardiac surgery. Furthermore, the relation between AF and the CHA2DS2VASc score has not been definitively established with respect to postoperative stroke. We retrospectively analyzed the records of all cardiac surgery performed at our institution between January 2008 and July 2013. Baseline characteristics, operative data, and postoperative outcomes were compared in patients who developed stroke with those who did not. Previously recognized stroke risk factors, including AF, were analyzed along with the CHADS2 and CHA2DS2VASc scores. A total of 3,492 consecutive patients were identified, of which 2,077 (60%) underwent valve surgery, 915 (26%) had coronary artery bypass grafting, 399 (11%) underwent combined coronary artery bypass grafting and valve procedures, and 101 (3%) had other cardiac operations. Postoperative ischemic strokes occurred in 44 patients (1.2%). The development of a stroke was associated with older age (74 – 12 vs 69 – 12, p [ 0.008), preoperative antiplatelet medication use (38.6% vs 24.5%, p [ 0.043), congestive heart failure (37% vs 20%, p [ 0.002), and greater CHADS2 (2.48 – 1.3 vs 1.98 – 1.1, p [ 0.015) and CHA2DS2VASc scores (4.2 – 1.8 vs 3.4 – 1.6, p [ 0.002). Multivariable analysis demonstrated that the CHA2DS2VASc score was the only independent predictor of postoperative strokes (odds ratio 1.25; 95% confidence interval 1.05 to 1.5, p [ 0.014). In conclusion, the CHA2DS2VASc score appears to predict postoperative strokes independent of the presence of AF. Ó 2015 Elsevier Inc. All rights reserved. (Am J Cardiol 2015;115:758e762)
The CHADS2 and CHA2DS2VASc scores have been validated as clinical tools to stratify the risk of stroke in patients with nonvalvular atrial fibrillation (AF).1,2 Additionally, these scores appear to predict postoperative strokes in patients who underwent coronary artery bypass grafting (CABG).3,4 This evidence is limited and has not addressed the relation between the CHA2DS2VASc score and preoperative AF, with respect to postoperative strokes. Furthermore, data are limited in its application in valvular and other cardiac operations and different surgical approaches. The purpose of the present study was to evaluate the ability of the CHADS2 and CHA2DS2VASc scores in predicting postoperative strokes in patients who underwent various cardiac surgeries. Methods After obtaining approval from the institutional review board, we analyzed the data of all cardiac surgery performed a Columbia University Division of Cardiology, Mount Sinai Heart Institute, Miami Beach, Florida and bDepartment of Internal Medicine, Mount Sinai Medical Center, Miami Beach, Florida. Manuscript received November 13, 2014; revised manuscript received and accepted December 19, 2014. There is no funding support for this study. See page 761 for disclosure information. *Corresponding author: Tel: (305) 674-2168; fax: (305) 674-2368. E-mail address: [email protected] (O. Santana).
0002-9149/15/$ - see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjcard.2014.12.037
at our institution from January 2008 to July 2013. The baseline characteristics, operative data, and postoperative outcomes were compared among patients who developed a stroke with those who did not. The definitions and variables from the Society of Thoracic Surgeons Adult Cardiac Surgery database were used. Postoperative AF was defined as newonset AF lasting more than 5 minutes, as documented by continuous telemetry, or 12-lead electrocardiogram, necessitating treatment. Stroke was defined as any confirmed neurologic deficit of abrupt onset that did not resolve within 24 hours, with new structural changes detected on computed tomography or magnetic resonance imaging. The strokes were considered postoperative, if they occurred in the period between the beginning of the operation and the patient’s death or discharge from the hospital. The CHADS2 and CHA2DS2VASc scores were calculated using the preoperative variables of congestive heart failure, hypertension, age, diabetes mellitus, previous stroke, vascular disease (including peripheral artery disease, myocardial infarction, and aortic plaque), and gender category.1,2 Continuous variables with a parametric distribution are reported as a mean standard deviation, whereas those with a nonparametric distribution are reported as a median and interquartile range (IQR or 25% to 75%). To compare continuous variables with a parametric distribution between groups, an independent samples t test was used. Continuous variables not following a parametric distribution were compared using the ManneWhitney U test. Categorical www.ajconline.org
Arrhythmias and Conduction Disturbances/CHA2DS2VASc Score Predicts Postoperative Stroke Table 1 Patient characteristics Variable
Age (Years) Women Body mass index (kg/m2) Diabetes mellitus Hypertension* Dyslipidemia† Heart failure History of atrial fibrillation Left ventricular ejection fraction (%) Chronic obstructive pulmonary disease Prior Peripheral vascular disease Prior Stroke Prior Myocardial infarction Prior Percutaneous coronary intervention Prior Renal replacement therapy Pre-operative creatinine Previous coronary artery bypass grafting Previous cardiac valve surgery Prior Infective endocarditis Pre-operative beta-blocker use Pre-operative anti-platelet use Pre-operative anticoagulation usex Pre-operative angiotensin converting enzyme inhibitor use CHADS2 CHA2DS2VASc
Stroke
p-value Yes (44)
69 12 1328 (38.5%) 28.2 5.3 1111 (32.2%) 3119 (90.5%) 2576 (74.7%) 684 (19.8%) 746 (21.6%) 53 12
74 12 19 (43.2%) 27.5 7.5 15 (34.1%) 41 (93.2%) 32 (72.7%) 17 (38.6%) 13 (29.5%) 54 11
0.008 0.6 0.4 0.9 0.7 0.9 0.002 0.3 0.6
11 (25%)
0.6
717 (20.8%) 411 304 1012 769
(11.9%) (8.8%) (29.4%) (22.3%)
69 (2%) 1.13 0.8 252 (7.3%) 223 117 2371 838 433 1144
(6.5%) (3.4%) (68.8%) (24.5%) (12.8%) (32.2%)
1.98 1.1 3.4 1.6
5 6 18 10
(11.4%) (13.6%) (40.9%) (22.7%)
1 (2.3%) 1.17 0.17 4 (9.1%) 4 2 30 17 8 19
(9.1%) (4.5%) (68.2%) (38.6%) (18.2%) (43.2%)
2.48 1.3 4.2 1.8
Table 2 Comparison of procedural characteristics between patients that did not suffer a stroke with those that did Variable
No (3448)
z
0.4 0.1 1 z
0.8
z z z
1 0.04 0.4 0.2
0.02 0.002
* These patients have a documented history of hypertension diagnosed and treated with medication, diet, and/or exercise, or prior documentation of blood pressure >140 mm Hg systolic or 90 mm Hg diastolic for patients without diabetes or chronic kidney disease (blood pressure >130 mm Hg systolic or 80 mm Hg diastolic on at least 2 occasions for patients with diabetes or chronic kidney disease). † These patients are on treatment for Dyslipidemia or meet any of the National Cholesterol Education Program criteria for Dyslipidemia: Total Cholesterol > 200 mg/dl (5.18 mmol/l), Low Density Lipoprotein (LDL) 130 mg/dl (3.37 mmol/l), High Density Lipoprotein < 40 mg/dl (1.02 mmol/l) in men and less than 50 mg/dl (1.20 mmol/l) in women. z Sample size too small for adequate statistical comparison. x These patients received either heparin or low molecular weight heparin within 48 hours of the surgery.
variables are reported as frequencies and percentages. For comparing these variables, a Fisher’s exact test or Pearson chi-square test was used. Binary logistic regression analyses were performed to identify variables related to stroke. After univariable analysis, variables with p values 0.2, including preoperative antiplatelet medication use and the CHA2DS2VASc score, and those previously associated with stroke, such as AF (both preoperative and postoperative), were analyzed using a multivariable logistic regression model. Variables that were already a component of the CHA2DS2VASc score, including congestive heart failure and the CHADS2 score, were excluded from the analysis. A p value
The CHADS2 and CHA2DS2VASc scores have been validated as clinical tools to stratify the risk of stroke in patients with nonvalvular atrial fibrillation (AF).1,2 Additionally, these scores appear to predict postoperative strokes in patients who underwent coronary artery bypass grafting (CABG).3,4 This evidence is limited and has not addressed the relation between the CHA2DS2VASc score and preoperative AF, with respect to postoperative strokes. Furthermore, data are limited in its application in valvular and other cardiac operations and different surgical approaches. The purpose of the present study was to evaluate the ability of the CHADS2 and CHA2DS2VASc scores in predicting postoperative strokes in patients who underwent various cardiac surgeries. Methods After obtaining approval from the institutional review board, we analyzed the data of all cardiac surgery performed a Columbia University Division of Cardiology, Mount Sinai Heart Institute, Miami Beach, Florida and bDepartment of Internal Medicine, Mount Sinai Medical Center, Miami Beach, Florida. Manuscript received November 13, 2014; revised manuscript received and accepted December 19, 2014. There is no funding support for this study. See page 761 for disclosure information. *Corresponding author: Tel: (305) 674-2168; fax: (305) 674-2368. E-mail address: [email protected] (O. Santana).
0002-9149/15/$ - see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjcard.2014.12.037
at our institution from January 2008 to July 2013. The baseline characteristics, operative data, and postoperative outcomes were compared among patients who developed a stroke with those who did not. The definitions and variables from the Society of Thoracic Surgeons Adult Cardiac Surgery database were used. Postoperative AF was defined as newonset AF lasting more than 5 minutes, as documented by continuous telemetry, or 12-lead electrocardiogram, necessitating treatment. Stroke was defined as any confirmed neurologic deficit of abrupt onset that did not resolve within 24 hours, with new structural changes detected on computed tomography or magnetic resonance imaging. The strokes were considered postoperative, if they occurred in the period between the beginning of the operation and the patient’s death or discharge from the hospital. The CHADS2 and CHA2DS2VASc scores were calculated using the preoperative variables of congestive heart failure, hypertension, age, diabetes mellitus, previous stroke, vascular disease (including peripheral artery disease, myocardial infarction, and aortic plaque), and gender category.1,2 Continuous variables with a parametric distribution are reported as a mean standard deviation, whereas those with a nonparametric distribution are reported as a median and interquartile range (IQR or 25% to 75%). To compare continuous variables with a parametric distribution between groups, an independent samples t test was used. Continuous variables not following a parametric distribution were compared using the ManneWhitney U test. Categorical www.ajconline.org
Arrhythmias and Conduction Disturbances/CHA2DS2VASc Score Predicts Postoperative Stroke Table 1 Patient characteristics Variable
Age (Years) Women Body mass index (kg/m2) Diabetes mellitus Hypertension* Dyslipidemia† Heart failure History of atrial fibrillation Left ventricular ejection fraction (%) Chronic obstructive pulmonary disease Prior Peripheral vascular disease Prior Stroke Prior Myocardial infarction Prior Percutaneous coronary intervention Prior Renal replacement therapy Pre-operative creatinine Previous coronary artery bypass grafting Previous cardiac valve surgery Prior Infective endocarditis Pre-operative beta-blocker use Pre-operative anti-platelet use Pre-operative anticoagulation usex Pre-operative angiotensin converting enzyme inhibitor use CHADS2 CHA2DS2VASc
Stroke
p-value Yes (44)
69 12 1328 (38.5%) 28.2 5.3 1111 (32.2%) 3119 (90.5%) 2576 (74.7%) 684 (19.8%) 746 (21.6%) 53 12
74 12 19 (43.2%) 27.5 7.5 15 (34.1%) 41 (93.2%) 32 (72.7%) 17 (38.6%) 13 (29.5%) 54 11
0.008 0.6 0.4 0.9 0.7 0.9 0.002 0.3 0.6
11 (25%)
0.6
717 (20.8%) 411 304 1012 769
(11.9%) (8.8%) (29.4%) (22.3%)
69 (2%) 1.13 0.8 252 (7.3%) 223 117 2371 838 433 1144
(6.5%) (3.4%) (68.8%) (24.5%) (12.8%) (32.2%)
1.98 1.1 3.4 1.6
5 6 18 10
(11.4%) (13.6%) (40.9%) (22.7%)
1 (2.3%) 1.17 0.17 4 (9.1%) 4 2 30 17 8 19
(9.1%) (4.5%) (68.2%) (38.6%) (18.2%) (43.2%)
2.48 1.3 4.2 1.8
Table 2 Comparison of procedural characteristics between patients that did not suffer a stroke with those that did Variable
No (3448)
z
0.4 0.1 1 z
0.8
z z z
1 0.04 0.4 0.2
0.02 0.002
* These patients have a documented history of hypertension diagnosed and treated with medication, diet, and/or exercise, or prior documentation of blood pressure >140 mm Hg systolic or 90 mm Hg diastolic for patients without diabetes or chronic kidney disease (blood pressure >130 mm Hg systolic or 80 mm Hg diastolic on at least 2 occasions for patients with diabetes or chronic kidney disease). † These patients are on treatment for Dyslipidemia or meet any of the National Cholesterol Education Program criteria for Dyslipidemia: Total Cholesterol > 200 mg/dl (5.18 mmol/l), Low Density Lipoprotein (LDL) 130 mg/dl (3.37 mmol/l), High Density Lipoprotein < 40 mg/dl (1.02 mmol/l) in men and less than 50 mg/dl (1.20 mmol/l) in women. z Sample size too small for adequate statistical comparison. x These patients received either heparin or low molecular weight heparin within 48 hours of the surgery.
variables are reported as frequencies and percentages. For comparing these variables, a Fisher’s exact test or Pearson chi-square test was used. Binary logistic regression analyses were performed to identify variables related to stroke. After univariable analysis, variables with p values 0.2, including preoperative antiplatelet medication use and the CHA2DS2VASc score, and those previously associated with stroke, such as AF (both preoperative and postoperative), were analyzed using a multivariable logistic regression model. Variables that were already a component of the CHA2DS2VASc score, including congestive heart failure and the CHADS2 score, were excluded from the analysis. A p value
