Prognostic implications of coronary artery stenosis and coronary spasm in patients with stable angina: 5-year follow-up of the Abnormal COronary VAsomotion in patients with stable angina and unobstructed coronary arteries (ACOVA) study.

BACKGROUND

In the Abnormal COronary VAsomotion in patients with stable angina and unobstructed coronary arteries study, we showed that 62% of patients with stable angina and unobstructed coronary arteries had coronary spasm. In this study, we sought to assess the 5-year prognosis in these patients.

METHODS

Data regarding the following endpoints were obtained: death, non-fatal myocardial infarction, coronary event (=cardiac death or non-fatal myocardial infarction), persistent angina and repeated coronary angiography. Quality of life was assessed using the Seattle Angina Questionnaire.

RESULTS

Among patients with unobstructed coronary arteries there were three deaths (2.9%) and no non-fatal myocardial infarction. Among those with obstructive CAD 15 died (13.8%) and three had a non-fatal myocardial infarction (2.8%). Patients with obstructive CAD had a higher rate of all-cause death and coronary events compared to those without (P = 0.004). Persistent angina was more prevalent in patients with unobstructed coronaries (P = 0.042). Prognosis of patients with unobstructed coronaries regarding hard clinical events, persistent angina and repeated coronary angiography was independent of the presence of coronary spasm (all P > 0.05). However, spasm patients were more likely to take nitrate medication at follow-up (P = 0.029).

CONCLUSION

Patients with stable angina and unobstructed coronary arteries have a favorable prognosis regarding mortality and non-fatal myocardial infarction after 5 years compared to patients with obstructive CAD irrespective of the presence of coronary artery spasm. However, persistent angina remains a common issue in patients with unobstructed coronary arteries leading to a similar frequency of repeated invasive procedures as in patients with obstructive CAD.