Nonobstructive Coronary Artery Disease and Risk of Myocardial Infarction

Abstract

IMPORTANCE Little is known about cardiac adverse events among patients with nonobstructive coronary artery disease (CAD). OBJECTIVE To compare myocardial infarction (MI) and mortality rates between patients with nonobstructive CAD, obstructive CAD, and no apparent CAD in a national cohort. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study of all US veterans undergoing elective coronary angiography for CAD between October 2007 and September 2012 in the Veterans Affairs health care system. Patients with prior CAD events were excluded. EXPOSURES Angiographic CAD extent, defined by degree (no apparent CAD: no stenosis >20%; nonobstructive CAD: ≥1 stenosis ≥20% but no stenosis ≥70%; obstructive CAD: any stenosis ≥70% or left main [LM] stenosis ≥50%) and distribution (1,2, or 3 vessel). MAIN OUTCOMES AND MEASURES The primary outcome was 1-year hospitalization for nonfatal MI after the index angiography. Secondary outcomes included 1-year all-cause mortality and combined 1-year MI and mortality. RESULTS Among37 674 patients, 8384 patients (22.3%) had nonobstructive CAD and 20 899 patients (55.4%) had obstructive CAD. Within 1 year, 845 patients died and 385 were rehospitalized for MI. Among patients with no apparent CAD, the 1-year MI rate was 0.11% (n = 8, 95% CI, 0.10%–0.20%) and increased progressively by 1-vessel nonobstructive CAD, 0.24% (n = 10, 95% CI, 0.10%–0.40%); 2-vessel nonobstructive CAD, 0.56% (n = 13, 95% CI, 0.30%–1.00%); 3-vessel nonobstructive CAD, 0.59% (n = 6, 95% CI, 0.30%–1.30%); 1-vessel obstructive CAD, 1.18% (n = 101, 95% CI, 1.00%–1.40%); 2-vessel obstructive CAD, 2.18% (n = 110, 95% CI, 1.80%–2.60%); and 3-vessel or LM obstructive CAD, 2.47% (n = 137, 95% CI, 2.10%–2.90%). After adjustment, 1-year MI rates increased with increasing CAD extent. Relative to patients with no apparent CAD, patients with 1-vessel nonobstructive CAD had a hazard ratio (HR) for 1-year MI of 2.0 (95% CI, 0.8–5.1); 2-vessel nonobstructive HR, 4.6 (95% CI, 2.0–10.5); 3-vessel nonobstructive HR, 4.5 (95% CI, 1.6–12.5); 1-vessel obstructive HR, 9.0 (95% CI, 4.2–19.0); 2-vessel obstructive HR, 16.5 (95% CI, 8.1–33.7); and 3-vessel or LM obstructive HR, 19.5 (95% CI, 9.9–38.2). One-year mortality rates were associated with increasing CAD extent, ranging from 1.38% among patients without apparent CAD to 4.30% with 3-vessel or LM obstructive CAD. After risk adjustment, there was no significant association between 1- or 2-vessel nonobstructive CAD and mortality, but there were significant associations with mortality for 3-vessel nonobstructive CAD (HR, 1.6; 95% CI, 1.1–2.5), 1-vessel obstructive CAD (HR, 1.9; 95% CI, 1.4–2.6), 2-vessel obstructive CAD (HR, 2.8; 95% CI, 2.1–3.7), and 3-vessel or LM obstructive CAD (HR, 3.4; 95% CI, 2.6–4.4). Similar associations were noted with the combined outcome. CONCLUSIONS AND RELEVANCE In this cohort of patients undergoing elective coronary angiography, nonobstructive CAD, compared with no apparent CAD, was associated with a significantly greater 1-year risk of MI...

Presentation, Clinical Profile, and Prognosis of Young Patients With Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA): Results From the VIRGO Study

“…Consequently, a standard protocol as used for MI‐CAD treatment may not apply uniformly to all MINOCA patients. These variations underscore the need for prospective pathophysiology‐driven studies that test primary and secondary treatments specific to MINOCA subtype 10, 54, 55, 56, 57…”

“…Recent evidence demonstrates that patients with MINOCA are distinct from patients with AMI with the classic culprit lesion—namely, >50% plaque‐mediated occlusion of the coronary artery (myocardial infarction due to coronary artery disease [MI‐CAD])—by having lower prevalence of the traditional cardiac risk factors and a lower but clinically significant annual mortality rate 1, 5, 6. Seen more commonly in women and young patients, existing literature on MINOCA is extrapolated from studies enrolling predominantly men and older patients, and this may limit opportunities to fully describe the different phenotypes of disease defined as MINOCA, their clinical profiles, and their associated outcomes 3, 6, 9, 10, 11…”

Variations in Use of Optimal Medical Therapy in Patients With Nonobstructive Coronary Artery Disease: A Population‐Based Study

“…Patients with nonobstructive CAD are at increased risk of major adverse cardiovascular events, compared with those with no CAD 4, 7, 8. However, there is less guidance on the best treatment for patients with nonobstructive CAD.…”

Clinical Relevance of Functionally Insignificant Moderate Coronary Artery Stenosis Assessed by 3‐Vessel Fractional Flow Reserve Measurement

“…Several studies investigated the prognostic impact of the extent of anatomical nonobstructive disease evaluated by coronary angiography9, 20 or coronary computed tomography angiography 8, 21, 22. In the CONFIRM (coronary CT angiography evaluation for clinical outcomes: an international multicenter registry) registry,22 patients with 2‐ or 3‐vessel involvement of nonobstructive (1–49% diameter stenosis) CAD on coronary computed tomography angiography had a 3‐fold higher risk of all‐cause mortality than normal subjects.…”

“…A recent study of deferred lesions showed a gradual trend of decreasing event rates from the FFR strata of 0.76 to 0.80 to the strata of 0.81 to 0.85 8. Studies based on angiography and coronary computed tomography angiography showed that the extent of nonobstructive disease has prognostic implications (coronary artery disease [CAD]) 8, 9, 10. However, information about the influence of the extent of physiologically defined “moderate” CAD is limited.…”