Performance of the AUB-HAS2 Cardiovascular Risk Index in vascular surgery patients.

The American University of Beirut (AUB)-HAS2 risk index is a recently published tool for preoperative cardiovascular evaluation. It is based on six data elements: history of Heart disease, symptoms of Heart disease (angina or dyspnea), Age ⩾ 75 years, Anemia (hemoglobin < 12 mg/dL), emergency Surgery, and vascular Surgery. This study analyzes the performance of a modified AUB-HAS2 index (excluding the vascular surgery element) in a broad spectrum of vascular surgery procedures. The study population consisted of 90,476 vascular surgeries registered in the American College of Surgeons National Surgical Quality Improvement Program database. The performance of the AUB-HAS2 index was studied in seven groups: carotid endarterectomy (CEA), open abdominal aortic aneurysm surgical repair (OAAA), endovascular aortic aneurysm repair, supra-inguinal bypass, infra-inguinal bypass, lower extremity thrombo-endarterectomy, and lower extremity angioplasty. The outcome measure was death, myocardial infarction, or stroke at 30 days after surgery. Each patient was given an AUB-HAS2 score of 0, 1, 2, or > 2 depending on the number of data elements s/he has. The AUB-HAS2 index was able to stratify risk in the majority of patients into low (< 3%, score 0), intermediate (3-10%, score 1-2), and high (> 10%, score > 2) (p < 0.0001). The receiver operating curve had an area of 0.71 in the overall group and it ranged from 0.60 in CEA patients to 0.75 in OAAA patients. In conclusion, the AUB-HAS2 index is a simple tool that can quickly and effectively stratify the risk of patients undergoing a broad spectrum of vascular surgeries into low, intermediate, and high.

AUB-HAS2 Cardiovascular Risk Index: Performance in Surgical Subpopulations and Comparison to the Revised Cardiac Risk Index.

Background The American University of Beirut (AUB)-HAS2 Cardiovascular Risk Index is a newly derived index for preoperative cardiovascular evaluation. It is based on 6 data elements: history of heart disease; symptoms of angina or dyspnea; age ≥75 years; hemoglobin <12 mg/dL; vascular surgery; and emergency surgery. In this study we analyze the performance of this new index and compare it with that of the Revised Cardiac Risk Index in a broad spectrum of surgical subpopulations. Methods and Results The study population consisted of 1 167 278 noncardiac surgeries registered in the American College of Surgeons National Surgical Quality Improvement Program database. Each patient was given an AUB-HAS2 score of 0, 1, 2, 3, or >3, depending on the number of data elements present. The performance of the AUB-HAS2 index was studied in 9 surgical specialty groups and in 8 commonly performed site-specific surgeries. Receiver operating characteristic curves were constructed for the AUB-HAS2 and Revised Cardiac Risk Index measures, and the areas under the curve were compared. The outcome measure was death, myocardial infarction, or stroke at 30 days after surgery. The AUB-HAS2 score was able to stratify risk in all surgical subgroups (P<0.001). In the majority of surgeries, patients with an AUB-HAS2 score of 0 had an event rate of <0.5%. The performance of the AUB-HAS2 index was superior to that of the Revised Cardiac Risk Index in all surgical subgroups (P<0.001). Conclusions This study extends the validation of the AUB-HAS2 index to a broad spectrum of surgical subpopulations and demonstrates its superior discriminatory power compared with the commonly utilized Revised Cardiac Risk Index.

A New Index for Pre-Operative Cardiovascular Evaluation.

BACKGROUND: Currently used indices for pre-operative cardiovascular evaluation are either powerful, but complex, or simple, but with weak discriminatory power. OBJECTIVES: This study sought to prospectively derive and validate a simple powerful index that can stratify the cardiovascular risk of patients undergoing noncardiac surgery. METHODS: The derivation cohort consisted of 3,284 prospectively enrolled adult patients undergoing noncardiac surgery at the American University of Beirut Medical Center. The validation cohort consisted of 1,167,414 patients registered in the American College of Surgeons National Surgical Quality Improvement Program database. The primary outcome measure was death, myocardial infarction, or stroke at 30 days after surgery. RESULTS: The primary outcome occurred in 38 patients (1.2%) in the derivation cohort. Multivariate logistic regression analysis in the derivation cohort identified 6 data elements to be included in the prediction model: age ≥75 years, history of heart disease, symptoms of angina or dyspnea, hemoglobin <12 mg/dl, vascular surgery, and emergency surgery. Each patient was assigned a Cardiovascular Risk Index (CVRI) of 0, 1, 2, 3, and >3 based on the number of data elements present. The incidence of the primary outcome increased steadily across the CVRI groups in both the derivation (0%, 0.5%, 2.0%, 5.6%, and 15.7%, respectively; p < 0.0001) and validation (0.3%, 1.6%, 5.6%, 11.0%, and 17.5%, respectively; p < 0.0001) cohorts. The discriminatory power of the new CVRI was further confirmed by constructing a receiver-operating characteristic curve that had an area under the curve of 0.90 in the derivation cohort and 0.82 in the validation dataset. CONCLUSIONS: This study reports a new index for pre-operative cardiovascular evaluation which has a strong discriminatory power that can effectively stratify patients into low- (CVRI 0 to 1), intermediate- (CVRI 2 to 3), and high-risk (CVRI >3) groups. This has important implications for the efficient triage and management of patients scheduled for noncardiac surgery.