June 2026

Microvascular angina is caused by abnormalities in the heart’s microscopic vessels. These microvessels cannot be imaged, thus making microvascular angina challenging to diagnose and often unrecognised. Affected patients usually present with typical angina symptoms but angiographically normal coronary arteries.

An 83-year-old woman presents with a rapid, irregular pulse and feeling unwell. An ECG shows sinus tachycardia with atrial premature beats. This case highlights the importance of considering acute infection as a reversible cause of sinus tachycardia and atrial fibrillation.