Khat chewing and acute myocardial infarction.

Fresh leaves from khat trees (Catha edulis Celestrasae) are chewed daily by over 20 million people in Yemen and East African countries. Chewing khat (qat) is a popular social habit which has spread to Yemeni, Somali or East African communities in the USA and UK. The pleasure derived from khat chewing is attributed to the euphoric actions of S-(−)cathinone, a sympathomimetic amine with properties similar to amphetamine. Although cathinone is restricted in the UK under the Misuse of Drugs Act 1971, khat possession and use are not. Cathinone increases blood pressure and heart rate through noradrenaline (norepinephrine) release from peripheral neurones similar to amphetamine. Controlled studies in human volunteers have shown increases in blood pressure after chewing khat coinciding with raised plasma cathinone concentrations. Cardiovascular complications from cathinone abuse may therefore be similar to those of amphetamine. We have noticed increasing numbers of patients presenting with acute heart attack in the evening either during or after a khat chewing session. This prospective study was therefore undertaken to examine whether khat chewing has a role in precipitating acute myocardial infarction.