A cluster randomized trial of objective risk assessment versus standard care for acute coronary syndromes: Rationale and design of the Australian GRACE Risk score Intervention Study (AGRIS).

BACKGROUND: Assessing risk and weighing the potential benefits from evidence-based therapies are essential in the clinical decision making process of optimizing care and outcomes for patients presenting with acute coronary syndromes (ACS). Such practices are advocated in international clinical guidelines of ACS care. While the GRACE risk score (GRS) is a guideline advocated, well-validated risk stratification tool, its utility in improving care and outcomes remains unproven, and its application has been limited in routine clinical practice. OBJECTIVE: This study will assess the effectiveness using the GRS tool and treatment recommendations during patient assessment on improving the application of guideline-recommended therapies in ACS care. DESIGN: This study employs a PROBE (prospective cluster [hospital-level] randomized open-label, blinded endpoint) design to evaluate objective measures of hospital performance, with clinical events adjudicated by a blinded event committee. This randomized study is nested within the established CONCORDANCE registry of ACS patients, with existing methods for data collection and monitoring of care and clinical outcomes. The hospital-level intervention is the integration of the GRS into routine ACS patient assessment process. The study will assess the use of early invasive management, prescription of guideline recommended pharmacology and referral to cardiac rehabilitation by hospital discharge; with the key composite clinical endpoint of cardiovascular death, new or recurrent myocardial infarction, in-hospital heart failure or cardiovascular readmission at 12 months. Health economic impacts of risk stratification implementation will also be evaluated. The study will recruit 3000 patients from 30 hospitals. SUMMARY: The AGRIS trial will establish the effect of routine objective risk stratification using the GRACE risk score on ACS care and clinical outcomes.

Risk stratification in the setting of non-ST elevation acute coronary syndromes 1999-2007.

It is unclear if clinician risk stratification has changed with time. The aim of this study was to assess the temporal change in the concordance between patient presenting risk and the intensity of evidence-based therapies received for non-ST-segment elevation acute coronary syndromes over a 9-year period. Data from 3,562 patients with non-ST-segment elevation acute coronary syndromes enrolled in the Australian and New Zealand population of the Global Registry of Acute Coronary Events (GRACE) from 1999 to 2007 were analyzed. Patients were stratified to risk groups on the basis of the GRACE risk score for in-hospital mortality. Main outcome measures included in-hospital use of widely accepted evidence-based medications, investigations, and procedures. Invasive management was consistently higher in low-risk patients than in intermediate- or high-risk patients (coronary angiography 66.7% vs 63.5% vs 35.3%, p <0.001; percutaneous coronary intervention 31.1% vs 22.0% vs 12.9%, p <0.001). Absolute rates of angiography and percutaneous coronary intervention in the high-risk group remained 24% and 15% lower compared to the low-risk group in the most recent time period (2005 to 2007). In-hospital use of thienopyridine, low-molecular weight heparin, and glycoprotein IIb/IIIa inhibitors showed a similar inverse relation with risk. Prescription of aspirin, ß blockers, statins, and angiotensin receptor blockers was inversely related to risk before 2004, although this inverse relation was no longer present in the most recent time period (2005 to 2007). Only in-hospital use of unfractionated heparin showed use concordant with patient risk status. In conclusion, despite an overall increase in the uptake of evidence-based therapies, most investigations and treatments are not targeted on the basis of patient risk. Clinician risk stratification remains suboptimal compared to objective measures of patient risk.