Postinfarction angina: definition, classification. pathophysiology and non-traditional therapy

Abstract

Risk stratification after a myocardial infarction identifying patients at high risk for reinfarction, sudden death and lethal ventricular arrhythmias, should be done after an infarction. The postinfarction angina ( P.I.A. ) is a frequent clinical event that places the patient in risk for these situations with high mortality. Postinfarction angina is chest pain or equivalent that occurs 24 hours or more after the onset of the myc)cardial infarction. It's considered early if it occurs within the first ten days; it is late between ten days and two months. The incidence is between 20% and 60%. Patients with prior angina, non-Q-wave M.I., have postinfarction angina more frequently, up to 85% when they have prior recent angina. There are two types : ischemia in the infarct zone, in 40%. Ischemia at a distance in 6()%. The three-vessel disease was present in 85% in P.I.A., more likely in ischemia in the infarct zone. The eccentric lesions type Il were in 71% in P.I.A. The coronary lesions by angioscopy can be classified into three types : thrombus, irregular surface or endothelial irregularity and xanthomatous plaque. The I -month mortality was 44% in ischemia at a distance and 15% in ischemia in the infarct zone; I-year mortality rates was 31% and 37% respectively. The

Percutaneous Transluminal Coronary Angioplasty (P.T.C.A.) is a true proceeding to relieve the myocardial ischemia, but it has high rates of acute occlusions and reestenosis. They made P.T.C.A. when medications did not relieve symptons, or cases with complex anathomy and multivessel disease, specially cases who had high surgical risk. In 29% developed recurrent angina over 15 months after a success P.T.C.A.

Recent myocardial infarction does not contraindicate coronary surgery and it is recomended C.A.B.G. be delayed for at least 4 weeks after and acute infarct, when the ejection fraction is less than 50%. Surgical mortality was 3.5 times higher in the non-Q wave than the Q-wave M.I. . The alternative interventional techniques are : I ) Coronary atherectomy, with three types, directional, high-speed rotational and extraction. 2) Laser angioplasty, with the most important one that is "Excimer" in which an inert gas is associated with an halogen, XeCI , that is the most reliable. 3 ) Intracoronary stents. The success of these techniques is high, 90%, but they can't get lower reestenosis rates, that is 35%; their low mortality has become very good alternatives in P.I.A.