Is transluminal coronary angioplasty mandatory after successful thrombolysis? Quantitative coronary angiographic study

Abstract

Percutaneous transluminal coronary angioplasty has been advocated as a mandatory procedure to prevent reocclusion after successful thrombolysis in acute myocardial infarction. This study describes our experience with both procedures over a 12 month period. Out of 105 patients catheterised in the acute phase of myocardial infarction, 64 were recanalised with 250,000 units of streptokinase, while in 25 patients recanalisation could not be achieved. In the remaining 16, the infarct related vessel was patent at the time of the procedure. Eighteen of the 78 patients who had a patent infarct related vessel at the end of the recanalisation procedure underwent transluminal angioplasty immediately afterwards. Post lysis angiograms were analysed quantitatively with a computerised measurement system. The contours of the relevant arterial segments were detected automatically. Reference diameter, minimal obstruction diameter, length of the lesions, and percentage diameter stenosis were averaged from multiple views. In 31% of our patients a diameter stenosis of less than 50% was found whereas one of 70% or more was seen in only 19%. Eleven stenotic lesions, recanalised at the acute stage, reoccluded in the short term, and in the long term eight other patients sustained a reinfarction in the same myocardial territory. Seventeen of these 19 recanalised lesions had a diameter stenosis of 58% or more. In view of these results, we felt justified in combining recanalisation and angioplasty in 18 patients selected from the most recent admissions. In these patients, the mean diameter stenosis decreased from 59% to 30% and mean pressure gradient from 41 to 8 mmHg. Late follow up showed reocculusion in one case. Though percutaneous transluminal coronary angioplasty does not seem to be mandatory at the acute stage in the majority of patients, it is feasible to undertake in one sitting and seems to prevent reocclusion in patients selected on the basis of quantitative angiographic criteria.