Myocardial infarction with normal coronary angiography compared with severe coronary artery disease without myocardial infarction: the crucial role of smoking Abdurrazzak A. Gehani, Abdul-Wahid Al-Mulla, Amer Chaikhouni, Abdul-Salam Ammar, Farouk Mahrous, Ramiz Tirkawi, Ali Ashraf and Hajar A. Hajar Background Why do some patients suffer acute myocardial ( ) infarction MI despite angiographically normal coronary arteries ( ) NL+MI whereas others enjoy an acute MI-free life despite ( ) extensive three-vessel disease 3VD-MI ? The present study contrasts these two groups to identify some differences in the risk profile. Methods In 10 000 patients admitted to the cardiology service, a first MI was confirmed in 2356 patients, of whom 1609 underwent coronary angiography. In 77 patients with MI, ( coronary angiography was found to be entirely normal NL + MI, ) 77/ 1609, 4.1% . These were contrasted to 123 patients with ( ) severe three-vessel coronary disease but no MI 3VD-MI . ( Results Patients with NL + MI were 13 years younger 42 8.3 ) ( ) vs 55 10.5, P  0.05 , with 33 patients 43% under the ( ) age 40 years, in contrast to only 9 patients 7.3% in the 3VD group being this age. Patients with NC + MI were more often ( ) current smokers 80.5% vs 29% in the 3VD group; P  0.01 . Patients with 3VD-MI were, on the other hand, more often ( ) diabetic 54% vs 9% in the NL + MI group; P  0.01 and had ( a higher cholesterol level 5.6 1.1 vs 4.9 1.0 Mmol/l, ) P  0.01 as well as a higher incidence of chronic stable ( ) ( angina 52% vs 22%; P  0.01 and heart failure 6% ) compared with 0% in the NL+MI group . Sixty-one out of 77 ( ) 79% NL+MI patients had a single risk factor, and in 87%, this was smoking alone. Diabetes mellitus was rare and never occurred alone in this group. Conclusion In patients who suffer MI despite normal coronary angiography, smoking is a major risk factor: In contrast, in patients with extensive coronary artery disease on angiography but no MI, diabetes rather than smoking is the dominant risk factor. The findings of this study support the view that the risk factors for stable and unstable coronary artery disease are different, as reflected by the contrast of the above groups at the extremes of the spectrum. Smoking appears to be a major ( risk factor for acute MI even with normal coronary ) angiography , whereas diabetes is a major risk factor for more severe but more stable coronary artery disease. J Cardiovasc Risk 8:1–8  2001 Lippincott Williams & Wilkins. Journal of Cardiovascular Risk 2001, 8:1–8 Keywords: myocardial infarction, normal coronary angiography, coronary artery disease, risk factors Department of Cardiology and Cardiac Surgery, Hamad Medical Corporation, Doha, Qatar Correspondence and requests for reprints to A. A. Gehani, MD, FRCP Edin, FACA, FESC, Consultant Cardiologist, Director of Coronary Care Units, Hamad General Hospital, P.O. Box 3050, Doha, Qatar. Tel: +974 4867188; fax: +974 4314564; e-mail: ibnafis@qatar.net.qa Received 09 November 1999 Revised 19 July 2000 Accepted 15 August 2000 Introduction Why is it that some patients do not suffer myocardial Ž . infarction MI despite extensive coronary artery dis- ease, whereas others sustain an MI with angiographi- cally normal coronary arteries? This subject continues to arouse interest, as evidenced by continuing publications  on the subject 1 . The present study is an attempt to draw a profile of two such groups. It presents our experience with 200 patients in these two highly se- lected categories. The groups were compared with re- gard to risk factors as well as clinical and angiographic profiles. Ž MI with angiographically normal coronary arteries NL .  MI has been recognized for several years, Khan and  Haywood reporting nine cases in 1974 2 . This was followed by several more reports, only a few of which, however, reported strictly ‘normal’ coronary angiogra- phy. More often, they included patients with ‘near-nor- mal’ coronary angiography or sometimes ‘insignificant’ coronary disease. In the present study, only proven MI with entirely normal angiography is included. The pres- ence of the slightest visible plaque was a cause for exclusion. To refine this group even further, only patients with a first MI were included. Previous MI may influence the picture in many ways, and such patients were excluded. Similarly, in the group with severe coronary artery disease, we included only those patients Ž . with severe  70% stenoses or total occlusions in all three main coronary arteries, that is the left anterior descending, the left circumflex, and the right coronary artery. This is the largest study of MI with entirely normal coronary angiography and the first to compare this group with patients who have extensive coronary artery dis- ease but no MI. It is only by comparing patients at the extremes of the spectrum that the differences may become apparent. 1350–6277  2001 Lippincott Williams & Wilkins Downloaded from https://academic.oup.com/eurjpc/article/8/1/1/5933958 by guest on 10 June 2023