Thrombosis within the left anterior descending coronary artery and left ventricle after high-dose nitrous oxide use.

We present a man in his 30s with acute anterior myocardial infarction due to thrombotic occlusion of the left anterior descending artery and subsequent left ventricular thrombus formation after high-dose recreational use of nitrous oxide (NO). Initial questioning for use of illicit substances was negative, but low vitamin B levels and severely elevated homocysteine levels prompted us to interrogate for the use of laughing gas. On questioning, the patient admitted to have used this substance, which he presumed to be innocent.