Natural history of patients with insignificant coronary artery disease

Abstract

Aims: 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.

Methods and results: 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).

Conclusion: 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.

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