In a retrospective study of patients undergoing elective coronary angiography, non-obstructive coronary artery disease (heart blockages), compared with no apparent coronary artery disease (no blockages), was associated with a significantly greater 1-year risk of heart attack and all-cause mortality.

After risk adjustment, there was no significant association between 1- or 2-vessel non-obstructive coronary artery disease (blockages in one or two arteries) and mortality, but there were significant associations with mortality for 3-vessel non-obstructive coronary artery disease (blockages in all three arteries).

Veterans with evidence of non-obstructive CAD on elective coronary angiography had a 2- to 4.5-fold greater risk for heart attack compared with those with no evidence of blockages and 1-year heart attack risk was found to increase progressively by the extent of blockages, rather than increasing abruptly when blockages became obstructive. The results of this study are published in Nov. 5 issue of JAMA.

Never tell your patients “that your coronaries are fine and they have nothing to worry about." Instead, one should say “There is evidence of atherosclerosis and while there is no need to panic, we need to address it.”

Remember there is nothing like “mild coronary artery disease." Up to 1 in 4 angiograms show minimal plaque or blockages.

Non-obstructive blockages mean presence of atherosclerotic plaque revealed during coronary angioplasty or angiography that does not appear to obstruct blood flow or result in angina symptoms.

These non-obstructive lesions occur in about 10-25% of patients undergoing elective angiography, and their presence has historically been characterized as "insignificant" or "no significant blockages in the medical literature even though multiple studies have shown plaque ruptures leading to heart attack commonly come from non-obstructive plaques.