1) The study examined over 120,000 emergency cardiac catheterization procedures from 614 hospitals to determine how often no significant coronary artery disease was found. 2) The results showed that flow-limiting coronary artery disease was present in 91.9% of cases, while no significant blockages were found in 8.1% of cases. 3) The authors concluded that finding no coronary artery disease was uncommon, and current practice activates primary angioplasty teams with reasonable specificity given the difficulty of perfectly distinguishing STEMI from other causes of symptoms.

1. Absence of Flow-Limiting Coronary Artery Disease Among Patients Undergoing Emergent Cardiac Catheterization For ST Segment Elevation Myocardial Infarction in the National Cardiovascular Data Registry CathPCI Registry: Implications for Primary Angioplasty Programs Kalon KL Ho, H Vernon Anderson, Richard E Shaw, Lloyd W Klein, James H Beachy, Christopher P Cannon, Harlan M Krumholz, Susan Fitzgerald, Anthony Hermann, Kristi Mitchell, John Rumsfeld, Ralph G Brindis, on behalf of the National Cardiovascular Data Registry

2. Author Disclosure Information The following relationships exist related to this presentation: CP Cannon: significant research grants from Accumetrics, AstraZeneca, Bristol-Myers Squibb, Glaxo Smith Kline, Merck, Sanofi-Aventis, Schering Plough RG Brindis: none J Rumsfeld: none K Mitchell: none A Hermann: none S Fitzgerald: none HM Krumholz: none JH Beachy: none LW Klein: none RE Shaw: none HV Anderson: none KKL Ho: none

3. Background Many hospitals have established primary angioplasty programs with a goal of providing consistently timely reperfusion for patients with suspected acute ST segment elevation myocardial infarction (STEMI). As the locus of control for activation of the cardiac catheterization laboratory (CCL) moves from the cardiologist to the emergency department (ED) and even to pre-hospital activation by emergency medical services, concerns have been raised about “false positive” activations of the primary angioplasty team.

4. Objective Estimate how often flow-limiting coronary artery disease (CAD) was NOT found among patients undergoing emergent cardiac catheterization for presumed STEMI in the National Cardiovascular Data Registry (NCDR) CathPCI Registry, a large multi-center cardiac catheterization and percutaneous coronary intervention (PCI) quality improvement and outcomes database.

5. Study Population From 01 January 2005 – 31 December 2006 120,676 diagnostic coronary angiograms 614 hospitals Procedural status coded as Emergent Ongoing ischemic dysfunction, or Cardiogenic shock Salvage CPR en route

6. Study Population Since the results of the angiogram (e.g., no CAD) can be used to determine retrospectively that STEMI was not the indication for the procedure, we did NOT use the admission symptom presentation to identify cases of suspected STEMI.

7. Results Procedural status: 98.7% emergent 1.3% salvage Angiographic results: 91.9% CAD* 8.1% no CAD* 4.9% no stenoses * CAD:  50% diameter stenosis in an epicardial coronary artery >2 mm in diameter

8. Correlates of No CAD Age: no CAD median 54 yrs; CAD median 61 yrs Sex: Men 6.6% no CAD Women 11.4% no CAD Cardiogenic shock: Present 4.7% no CAD Absent 7.6% no CAD Race: Caucasian 7.3% no CAD All others 11.7% no CAD Admission Source: Outpatient 11.9% no CAD ED 7.8% no CAD Transfer 6.1% no CAD from acute care facility

9. Effect of Thrombolytic Therapy Angiographic results: Thrombolytics given (7.8% of cases) 97.4% CAD* 2.6% no CAD* 1.4% no stenoses No thrombolytics given 92.4% CAD* 7.6% no CAD* 4.6% no stenoses * CAD:  50% diameter stenosis in an epicardial coronary artery >2 mm in diameter

10. Outcomes Revascularization Patients with CAD 82.9% ad hoc PCI 9.6% CABG Patients without CAD 4.4% ad hoc PCI 0.7% CABG In-hospital Mortality Patients with CAD 6.0% Patients with no CAD 4.9%

11. Limitations Self-reported data without 100% auditing Information not uniformly available on suspected STEMI as a specific indication for angiography and other clinical details (e.g., the extent or location of electrocardiographic abnormalities, biomarker results, cocaine use, left ventricular hypertrophy, and the final clinical diagnoses) The presence of CAD with  50% diameter stenosis does not mean that the patient was necessarily suffering a STEMI

12. Conclusions Among patients undergoing emergent or salvage diagnostic cardiac catheterization nationwide in the NCDR CathPCI Registry (>120,000 cases): Finding NO angiographically-apparent flow-limiting CAD was uncommon (<10%). No clinical finding or test will perfectly discriminate STEMI from “STEMI mimics” Current clinical practice appears to activate primary PCI teams with reasonable specificity.

13. Acknowledgements The authors wish to acknowledge the invaluable contributions of The participants of the CathPCI Registry The analytical team at the Duke Clinical Research Institute (Fang-Shu Ou, Barbara Lytle, Matthew Roe)