[Demonstration of reversible myocardial ischemia in necrotic akinetic areas using endocoronary ECG during angioplasty].

The presence of ischaemic myocardial tissues in necrotic territories and the usefulness of revascularizing these territories are controversial matters. We have determined the existence of this phenomenon by the per-angioplastic intracoronary ECG method, and we have compared the sensitivities of intracoronary ECG and surface ECG. Intracoronary EVG is achieved by using the mobile teflon-coated guide wire of coronary angioplasty as a unipolar epicardial electrode. Being epicardial and localized, the electrode explores a limited area of the myocardium, distal to the artery being dilated and momentarily occluded by the balloon during inflations. The study involved 12 patients (mean age 53.7 years) who presented with the following criteria of admission: transmural myocardial infarction, presence of a Q wave on two leads, akinetic segment at ventriculography and coronary stenosis or occlusion amenable to angioplasty. Patients with collateral circulation between the larger epicardial vessels were excluded. Intracoronary ECG recordings were taken before, during and after inflations. In 9 out of 12 patients the ST segments was elevated by 1.3 mV on average between inflations (S.D. 3.14 mV) and by 4.8 mV (S.D. 3.99 mV) during inflations. These high standard deviations were due to major inter- and intra-individual variations of ST. The difference was significant (p less than 0.05) at variance analysis. No variation of ST was observed in 3 patients. Only one of the 12 patients had elevated ST on both surface ECG and intracoronary ECG tracings. Thus, intracoronary ECG is a sensitive method to evaluate myocardial ischaemia during coronary angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)