Natural history of patients with insignificant coronary artery disease

Approximately 30% of patients undergoing coronary angiography for chest pain have insignificant coronary artery disease (ICAD). The subsequent health status of these patients is largely unknown. The current study was a cross-sectional, longitudinal comparison of health status outcomes 12 months following angiography, in a cohort of patients with stable chest pain and ICAD to: (i) patients with significant coronary artery disease (CAD) and (ii) a healthy control cohort.

Patients undergoing elective angiography for chest pain were recruited and classified as CAD (coronary stenosis ≥50%) or ICAD. Clinical and health-related quality-of-life (HRQoL) data were collected at baseline, 1, 6, and 12 months following angiography. The 12-month health status was cross-sectionally compared with a healthy control group recruited from the same geographic zone. Among 758 patients undergoing coronary angiography, 253 (33%) had ICAD. Insignificant coronary artery disease patients were younger, more often female, and had less cardiac risk factors than CAD patients. At 12 months, 48% of ICAD and 59% of CAD patients were chest pain-free, and both groups had similar Short-Form 36 Physical Component Summary (PCS) scores (41 ± 11 vs. 41 ± 11 for ICAD and CAD patients, respectively, P > 0.05). However, at 12 months, both the ICAD and CAD patients had significantly lower PCS scores compared with healthy controls (41 ± 11 vs. 49 ± 11, P < 0.05 for both CAD and ICAD).

Although ICAD patients are frequently considered ‘normal’ from a cardiac perspective, they often have residual chest pain and impaired HRQoL at 12 months. Novel strategies are needed to manage ICAD patients to improve health outcomes.

This study was registered with the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au, trial identifier ACTRN12610000801011).