The efficacy of excimer laser pretreatment for calcified nodule in acute coronary syndrome

Comparison of the efficacy of excimer laser coronary angioplasty for ST-segment elevation myocardial infarction with onset-to-balloon time

Excimer laser coronary angioplasty (ELCA) vaporizes plaques and thrombi, provides better microcirculation, and reduces peripheral embolism when treating acute coronary syndrome. Studies on the efficacy of ELCA for long onset-to-balloon time ST-segment elevation myocardial infarction (STEMI) are limited. Thus, we aimed to examine the efficacy of ELCA for STEMI using the onset-to-balloon time (OBT). A total of 319 patients with STEMI who underwent percutaneous coronary intervention from 2009 to 2012 and from 2015 to 2019 were enrolled. Patients who underwent PCI in 2009-2012 were considered the conventional group, and those treated with ELCA in 2015-2019 were considered the ELCA group. Patients were stratified by OBT. The endpoints were the final thrombolysis in myocardial infarction (TIMI) grade, myocardial blush grade (MBG), and slow-flow or no-reflow phenomenon during the procedure. The ELCA group had 167 patients, and the conventional group had 123. There was no significant difference in achieving final TIMI 3 between the groups. The acquisition rate of final MBG 3 was significantly higher in the ELCA than in the conventional group (79.6% vs. 65.9%; P = 0.01). There was a significant difference between the groups with OBT 12-72 h (82.1% vs. 56.0%; P = 0.031). The slow- or no-reflow incidence during the procedure was significantly lower in the ELCA than in the conventional group with OBT 12-72 h (17.8% vs. 52.2%; P = 0.019). ELCA improves the MBG and reduces intraoperative slow- or no-reflow phenomenon in patients with STEMI, 12-72 h after onset. ELCA will be useful in preventing peripheral embolism in patients with long onset-to-balloon time STEMI.

Optical Coherence Tomography in Vulnerable Plaque and Acute Coronary Syndrome

Optical coherence tomography (OCT) is an intravascular imaging technique that uses near-infrared light. OCT provides high-resolution cross-sectional images of coronary arteries and enables tissue characterization of atherosclerotic plaques. OCT can identify plaque rupture, plaque erosion, and calcified nodule in culprit lesions of acute coronary syndrome. OCT can also detect important morphologic features of vulnerable plaques such as thin fibrous caps, large lipid cores, macrophages accumulation, intraplaque microvasculature, cholesterol crystals, healed plaques, and intraplaque hemorrhage.

Ostial left circumflex lesion with calcified nodule successfully treated with excimer laser coronary atherectomy and drug-coated balloon

Stenting for severely calcified lesions has a higher risk of stent restenosis or stent failure than stenting for lesions without calcification, and stenting for complex lesions including ostial or bifurcation lesions sometimes causes plaque shift which leads to side branch occlusion. A calcified nodule (CN) is considered one of the culprits for stable angina or acute coronary syndrome. However, the optimal strategy for this lesion is not well clarified. We report a patient who presented stable angina with a CN at the ostial left circumflex artery. In this case, pretreatment with excimer laser coronary atherectomy (ELCA) and scoring balloon dilatation followed by drug-coated balloon (DCB) dilatation successfully prevented plaque shift caused by stenting in the acute phase. In addition, it also maintained the patency in the late phase. Furthermore, we observed the CN lesions at preprocedural, postprocedural, and late phase by optical coherence tomography. ELCA, which has a unique debulking technique, and scoring balloon dilatation followed by DCB dilatation might offer an alternative treatment for ostial CN lesions instead of stenting. 〈Learning objective: The optimal strategy for severely calcified lesions with calcified nodule is controversial because the prevalence of calcified nodule is rare and stent failure is more common in calcified lesions. In particular, regarding a calcified nodule located in ostial left circumflex coronary artery lesion, excimer laser coronary atherectomy and scoring balloon dilatation followed by drug-coated balloon may give an alternative treatment to avoid stenting.〉.

Comparison of 0.9-mm and 1.4-mm catheters in excimer laser coronary angioplasty for acute myocardial infarction

Excimer laser coronary angioplasty (ELCA) is a unique revascularization modality that can vaporize plaque and thrombus. Compared to thrombus aspiration therapy, ELCA is reported to provide better microcirculation and reduced peripheral embolism in treatment for acute coronary syndrome. Excimer laser catheters come in various sizes, and we sought to compare the 0.9- and 1.4-mm-diameter catheters. We retrospectively enrolled 90 acute myocardial infarction (AMI) patients who underwent primary percutaneous coronary intervention with excimer laser from August 2013 to March 2017 in our hospital. Patients were grouped by diameter of catheter that had been used, the 0.9 mm group (n = 51) and 1.4 mm group (n = 39). We evaluated myocardial perfusion, procedural success rate, short-term outcome, lesion crossability, and complications between the two groups. The percentage of patients whose final thrombolysis in myocardial infarction (TIMI) grade was 3 (0.9 mm 86.3% vs 1.4 mm 89.7% p = 0.75) and final myocardial blush grade (MBG) was 3 (0.9 mm 72.5% vs 1.4 mm 69.2% p = 0.82) was similarly high for both groups. Procedural success rate, in-hospital major adverse cardiac events (MACE), lesion crossability, and complications were also similar. This study showed that efficacy of 0.9 and 1.4 mm excimer laser catheter was equivalent in ELCA for AMI patients. If one takes into account lesion crossability, debulking effects, and the stunned platelets phenomenon, the 0.9 mm excimer laser catheter is sufficient for ELCA in AMI patients.