Abstract

Nonobstructive coronary artery disease (NCAD)occurs in 10% to 25% of patients undergoing elective coronary angiography, while nonobstructive acute coronary syndrome (NACS) accounts up to 6% of patients with troponin-positive ACS. In Yemen, prior studies have assessed outcomes among myocardial infarction (MI)khat chewers, who had nonobstructive lesions on angiography. However; correlation between NACS and Khat use is yet not discussed. Our study aimed to defining the clinical outcomes of patients, presenting with unstable angina (UA) or non ST segment elevation myocardial infarction (NSTEMI), but had stenosis ≤ 50% on angiography. Our main goal is to show the association between outcomes and khat chewing among patients with NASC. Data for this retrospective study were obtained from the sector of health care and related clinics at the Yemeni Petroleum Company in Aden- from January 2005 through September 2010. The study group consisting of 114 to ACS patients was divided into two subgroups: patients with stenosis < 20% and patients with stenosis more than 20 but less than50%. They were compared with patients in a control group (n=213), who had critical coronary stenosis, sufficient enough to warrantenough (≥70%) percutaneous coronary intervention (PCI). Our results showed that patients with NACS were more likely to be female, younger, with fewer risk factors, compared to the control. MI or PCI occurred was in 1.75 % or 3.5% of patients with NACS and in 5.16% or 17.37% (respectively) of patients with critical obstructive ACS. Cardiac death was observed less frequently in patients with NACS, compared to those with critical obstructive disease (1.75 % vs 4.23%). Sub analysis of the study group showed that, the 2nd subgroup patients (stenosis 20%-50%) were older male with an increasing frequency of nondiabetic patients and heavy khat chewing, compared to the 1st subgroup (stenosis<20%). Follow-up data showed that no deaths in the 1st subgroup and two cardiac deaths (3.7%) in the 2nd (P=0.001). Rehospitalization, PCI or cardiac decompensation were found significant in the 2nd subgroup. We concluded that the prognosis of patients with nonobstructive ACS was better than that of patients with critical obstructive ACS; although patients with stenosis 20-50% had a worse prognosis than did those with less stenosis or normal coronary arteries.