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Frequency of negative coronary arteriographic findings in patients with chest pain is related to community practice patterns.

OBJECTIVE
To determine factors contributing to the relatively high frequency and variability (10% to 30%) of finding no significant coronary disease by coronary angiography in patients with chest pain.


STUDY DESIGN
Retrospective, comparative analysis of practice patterns at 3 southeastern Michigan hospitals and a composite sample from New York State.


PATIENTS AND METHODS
Medical records for 7668 patients were reviewed to determine the frequency of negative coronary arteriographic findings in patients undergoing chest pain evaluation. A private practice allopathic community hospital with interventional cardiologists and a private practice osteopathic community hospital with diagnostic facilities (DiagCommunity) were compared with a university hospital with full-time salaried interventional cardiologists and a sample of 17 New York hospitals.


RESULTS
Of the 7668 coronary angiograms at all centers, 39.7% were performed to assess patients with stable chest pain. There was no significant obstruction found in 16.5%, and the frequency was not different between the Michigan (17.8%+/-3.8%) and New York (14.2%) hospitals. The DiagCommunity had the highest proportion (22%; P < .001 vs others). On review of the negative coronary arteriographic findings, normal or near normal coronary arteriographic findings were infrequent (range, 2.4%-6.6%) but higher in the DiagCommunity (6.6% vs 2.9%+/-1.6%; P < .0001).


CONCLUSIONS
The frequency of finding no significant coronary disease by arteriography in patients with chest pain is similar in southeastern Michigan hospitals and comparable to an established external database. Cardiology self-referral and personal gain does not seem to be a major factor in selection of patients for invasive studies.