Quantitative Coronary Angiographic Analysis of Spasm and Elastic Recoil After High Speed Rotational Atherectomy
Authors: POMERANTSEV EUGENE V. , FITZGERALD PETER J. , SHAW RICHARD E. , WALTON ANTONY S. , SANDERS WILLIAM J. , YEUNG ALAN , YOCK PAUL G. , OESTERLE STEPHEN N. , STERTZER SIMON H. 
Published: June 2007

This study evaluates the short‐term changes in coronary artery segments treated with high speed rotational atherectomy (HSRA). Quantitative coronary angiographic (QCA) analysis indices, such as degree of expected ablation, elastic recoil, and segmental spasm, were examined in 133 patients and restudied 24 hours after HSRA. The study was also designed to compare the early results of three different HSRA strategies: stand‐alone (SA) HSRA; HSRA with adjunctive high (≥ 4 atm) pressure (HP BA) and low (≥ 2 atm) pressure balloon angioplasty (LP BA). Previous studies have suggested negligible elastic recoil after HSRA as well as demonstrated the possibility of further continuous improvement in vessel patency up to 24 hours postprocedure. From a total of 656 patients treated with HSRA, a cohort of 133 patients with successful HSRA of 167 lesions were restudied angiographically at 24 hours. Serial QCA evaluation of the treatment site was performed. Analysis of the relative gain in minimal luminal diameter (MLD) assessed at 24 hours postprocedure showed that the highest gain group (> 40%) had narrower initial lesions compared to moderate gain (1%–40%), or MLD loss groups (MLD 0.5 ± 0.4 mm vs 1.0 ± 0.3 and 1.5 ± 0.4, respectively, P < 0.01). The initial percent diameter stenosis was also higher in the high gain group (77.1 ± 16.0 vs 61.9 ± 11.8 and 53.0 ± 11.9, P < 0.01). Immediately postprocedure there was a significant increase in MLD and a decrease in percent diameter stenosis. There was no difference in residual lesion characteristics postprocedure. While progressive MLD decrease was observed in the loss group (MLD postprocedure 1.6 ± 0.5 and 1.2 ± 0.6 at 24 hours, P < 0.01), a continuous increase in MLD was noted in the high gain group (MLD postprocedure 1.7 ± 0.5 mm vs at 24 hours 2.0 ± 0.5 mm, P < 0.01). The high gain group was characterized by the most lesion debulking, the most pronounced segmental spasm, and the least elastic recoil. Adjunctive HP BA was associated with the largest size vessels (D ref. in SA HSRA group was 2.6 ± 0.8 mm vs 2.9 ± 0.6 mm in LP BA and 3.0 ± 0.7 mm in HP BA groups, P < 0.01), the lowest elastic recoil (SA HSRA 23.8%± 20.9% vs LP BA 15%± 16.8% and HP BA 5.7%± 14.4%, P < 0.05), and the highest incidence of vessel dissection (SA HSRA 8.1% vs LP BA 14.7% and HP BA 34.0%, P < 0.05). However, these larger vessels underwent the least amount of lesion debulking (SA HSRA 46.4%± 27.2% vs LP BA 38.6%± 24.0% and HP BA 30.5%± 19.5%, P SA HSRA vs. HP BA < 0.001). There are measurable degrees of elastic recoil and local spasm observed after HSRA. HSRA of the most severe lesions yields the highest procedural gain, the lowest elastic recoil and the highest index of lesion ablation. In addition, some late increase in the MLD due to the resolution of spasm is observed at 24 hours postprocedure. SA HSRA is associated with higher degrees of expected lesion ablation. This is comparable to the degree of improvement in MLD, where adjunctive percutaneous transluminal coronary angioplasty is utilized as assessed at 24 hours postprocedure. HSRA with adjunctive HP BA yields immediate results showing the least elastic recoil and spasm at the expense of the highest incidence of dissection and side branch loss.