Myocardial infarction with non-obstructive coronary artery caused by coronary artery spasm and an increase in serum homocysteine: a case report.

BACKGROUND

Although elevated homocysteine levels have emerged as risk factors for cardiovascular diseases, the associations between homocysteine levels and coronary artery spasm are not well established. We present a case in coronary artery spasm resulted myocardial infarction merged severe high level of serum homocysteine without conventional coronary risk factors.

CASE SUMMARY: A 57-year-old male was referred to our hospital because of chest pain. Macrocytic anaemia with a decrease in the serum vitamin B12 concentration and an increase in the serum homocysteine concentration was appeared. Endoscopy was performed first due to concerns about gastritis or bleeding risk, followed by coronary angiography. He was diagnosed autoimmune gastritis. Coronary angiography revealed no arterial stenosis, and coronary artery spasm with ischaemic ST-T changes on the electrocardiogram appeared with the intracoronary administration of acetylcholine. Inferior myocardial infarction appeared via magnetic resonance imaging. Calcium channel antagonists and vitamin B12 were treated to improve coronary artery spasm and homocysteine levels. After 1 year with adjusted serum homocysteine levels, the patient had no coronary artery spasm, and his chest pain disappeared even with the intracoronary administration of acetylcholine.

DISCUSSION: Elevated serum homocysteine levels have a possibility to worsen coronary artery spasm. We concluded that serum homocysteine levels might be a new basis for devising strategies to prevent coronary artery spasm and that optimizing serum homocysteine levels may alleviate the underlying exacerbation of myocardial ischaemia.