Prevalence and extent of obstructive coronary artery disease among patients undergoing elective coronary...

Area of Science:

• Cardiology
• Health Services Research

Background:

• Physicians in New York perform cardiac catheterizations twice as often per capita as in Ontario for stable patients.
• The role of patient selection in these disparities and its impact on detecting obstructive coronary artery disease (CAD) remain unclear.

Purpose of the Study:

• To evaluate the extent of obstructive CAD in patients undergoing elective cardiac catheterization.
• To compare the probability of detecting obstructive CAD between New York and Ontario.

Main Methods:

• An observational study analyzed 18,114 patients from New York and 54,933 from Ontario undergoing elective cardiac catheterization (Oct 2008-Sep 2011).
• Obstructive CAD was defined as ≥50% stenosis in the left main or ≥70% in a major epicardial vessel.
• Logistic regression models estimated predicted probabilities of obstructive CAD.

Main Results:

• The observed rate of obstructive CAD was significantly lower in New York (30.4%) than in Ontario (44.8%).
• New York had a lower percentage of patients with left main or 3-vessel CAD (7.0% vs 13.0%).
• A higher proportion of New York patients with a low predicted probability of obstructive CAD underwent catheterization (19.3% vs 41%).

Conclusions:

• Patients undergoing elective cardiac catheterization in Ontario were more likely to have obstructive CAD than those in New York.
• This disparity is associated with a greater number of New York patients with a low predicted probability of CAD undergoing the procedure.