Nonobstructive Coronary Artery Disease Linked to Adverse Outcomes

Nonobstructive coronary artery disease (CAD) is thought not to restrict blood flow and therefore not to increase risk for adverse cardiac events. However, prior studies have shown that most myocardial infarctions (MIs) are associated with nonobstructive stenoses.

To determine whether nonobstructive CAD is associated with risk for MI and mortality, investigators conducted a retrospective analysis of nearly 38,000 elective angiography patients in the Veterans Affairs health system. Angiographic extent of CAD was characterized according to standard definitions (no apparent CAD, no stenosis >20%; nonobstructive CAD, ≥1 stenosis ≥20% but no stenosis ≥70%; and obstructive CAD, any stenosis ≥70% or any left-main stenosis ≥50%); CAD severity was als…