Role of coronary spasm in the genesis of myocardial infarction: study of a case treated by isosorbide dinitrate in situ then by transluminal angioplasty.

We report the observation of a 62-year-old patient who was admitted for unstable angina. A prolonged chest pain (more than two hours) with a major electrocardiographic lesion in the posterior leads needed an urgent coronary arteriography in order to attempt a recanalization. Antecedents of arteriopathy of the lower limbs with aortobifemoral bypass required an axillary artery right side approach. A selective right coronary opacification showed complete occlusion at the junction of segments 1 and 2. An intracoronary injection of isosorbide dinitrate relieved a coronary spasm and allowed a complete visualization of the right coronary artery. This appeared to be very atherosclerotic with several severe narrowings, and a subocclusive lesion at the site of the initial occlusion. Percutaneous transluminal coronary angioplasties (PTCA) were performed and led to real 'restructuring' of the right coronary artery. The clinical outcome was excellent without recurrent angina pectoris. An angiographic control performed 6 months after PTCA demonstrated the persistence of the coronary recanalization and an evident improvement of the segmental contractility. This report emphasizes the role of coronary spasm in the genesis of myocardial infarction and shows that PTCA may be performed as a first approach at the acute phase of myocardial infarction; to our knowledge it is the first PTCA performed by an axillary approach at the acute stage of myocardial infarction.