ELASTIC RECOIL AFTER TRANSLUMINAL CORONAR Y ANGIOPLASTY - IMPLICATIONS OF CLINICAL AND ANGIOGRAPHIC DATA

Secondary elastic recoil after transluminal coronary angioplasty is a constant and immediate phenomenon after successful coronary angioplast y. It was studied by quantitative coronary angiography in 75 consecuti ve patients undergoing transluminal coronary angioplasty. This procedu re was performed on lesions presumed to be responsible for the clinica l presentation. The population was divided into 3 groups: stable angin a (25 patients), unstable angina (25 patients) and recent post-infarct ion ischaemic syndromes (25 patients). There were 57 men and 18 women (mean age 59 +/- 11 years) with 31 left anterior descending (LA), 29 r ight coronary (RC) and 15 left circumflex (Cx) dilatations. The lesion s dilated were excentric in 29 cases and calcified in 37 cases whereas only one thrombus was detected at coronary angiography. The elastic r ecoil appreciated 10 mn after the last balloon inflation was 0.97 +/- 0.28 mm for the whole population. There was no significant difference between the 3 groups studies (respectively 0.94 +/- 0.24 mm; 0.96 +/- 0.26 mm; 0.99 +/- 0.33 mm). This appeared to be greater than the RC (1 .06 +/- 0.30 mm) with respect to the Cx (0.86 +/- 0.23: p < 0.02) or L AD (0.92 +/- 0.25 mm: p < 0.04). Overall, a balloon to vessel diameter ratio > 1 and a lesion length > 10 mm were parameters predicting grea ter secondary elastic recoil (p < 0.07 and p < 0.001 respectively), wh ereas the degree of excentricity only played a role in the post-infarc tion ischaemic syndromes and calcification only in unstable angina (p < 0.01 and p < 0.001 respectively). Therefore, after successful transl uminal coronary angioplasty, the immediate loss in diameter is 30% of initial gain and this phenomenon, largely dominated by the elastic cha racter of the coronary artery, is maximal in lesions most stretched by an oversized balloon and/or lesions > 10 mm in length; on the other h and, the initial clinical presentation has no influence on this result .