[A prospective study on the safety and efficacy of excimer laser coronary angioplasty for the treatment of degenerated great saphenous vein graft]

Objective: To explore the safety and efficacy of excimer laser coronary angioplasty (ELCA) for the treatment of degenerated great saphenous vein graft (SVG). Methods: This is a single-center, prospective, single-arm study. Patients, who were admitted to the Geriatric Cardiovascular Center of Beijing Anzhen Hospital from January 2022 to June 2022, were consecutively enrolled. Inclusion criteria were recurrent chest pain after coronary artery bypass surgery (CABG), and coronary angiography confirmed that the SVG stenosis was more than 70% but not completely occluded, and interventional treatment for SVG lesions was planned. Before balloon dilation and stent placement, ELCA was used to pretreat the lesions. Optical coherence tomography (OCT) examination was performed and postoperative index of microcirculation resistance (IMR) were assessed after stent implantation. The technique success rate and operation success rate were calculated. The technique success was defined as the successful passage of the ELCA system through the lesion. Operation success was defined as the successful placement of a stent at the lesion. The primary evaluation index of the study was IMR immediately after PCI. Secondary evaluation indexes included thrombolysis in myocardial infarction (TIMI) flow grade, corrected TIMI frame count (cTFC), minimal stent area and stent expansion measured by OCT after PCI, and procedural complications (Ⅳa myocardial infarction, no reflow, perforation). Results: A total of 19 patients aged (66.0±5.6) years were enrolled, including 18 males (94.7%). The age of SVG was 8 (6, 11) years. The length of the lesions was greater than 20 mm, and they were all SVG body lesions. The median stenosis degree was 95% (80%, 99%), and the length of the implanted stent was (41.7±16.3)mm. The operation time was 119 (101, 166) minutes, and the cumulative dose was 2 089 (1 378, 3 011)mGy. The diameter of the laser catheter was 1.4 mm, the maximum energy was 60 mJ, and the maximum frequency was 40 Hz. The technique success and the operation success rate were both 100% (19/19). The IMR after stent implantation was 29.22±5.95. The TIMI flow grade of patients after ELCA and stent implantation was significantly improved (all P>0.05), and the TIMI flow grade of all patients after stent implantation was Grade Ⅲ. The cTFC decreased significantly after ELCA (33.2±7.8) and after stent placement (22.8±7.1) than preoperative level (49.7±13.0) (both P<0.001). The minimum stent area was (5.53±1.36)mm², and the stent expansion rate was (90.0±4.3)%. Perforation, no reflow, type Ⅳa myocardial infarction and other complications were not observed. However, postoperative high-sensitivity troponin level was significantly increased ((67.937±33.839)ng/L vs. (5.316±3.105)ng/L, P<0.001). Conclusion: ELCA is safe and effective in the treatment of SVG lesions and could improve microcirculation and ensure full expansion of stent.

[Comparison of prognostic value of (18)F-FDG PET/CT myocardial metabolism imaging and coronary collateral circulation in patients with CTO lesions]

Objective: To evaluate the location, extent of viable myocardial of chronic total coronary occlusions(CTO)lesions by (18)F-FDG PET myocardial metabolism imaging and then compare with coronary collateral circulation(CCC) to evaluate the prognostic evaluation in patients with CTO lesions. Methods: A total of Sixty consecutive patients with CTO lesions referred for viability assessment from April 2016 to April 2017 in Department of Cardiology, Beijing Anzhen Hospital were included in the study. These patients underwent (99m)Tc-sestamibi ECG-gated SPECT rest myocardial perfusion imaging and ECG-gated (18)F-FDG PET/CT myocardial metabolic imaging, as well as coronary arteriography were recruited in this study. LV functional parameters(EDV, ESV, and LVEF) were analyzed by QGS software. The extent of CCC to the area of CTO related artery was graded as poorly, or well developed collaterals, assessed by Rentrop classification. All patients were followed up for a median of 17 months(range 12-20 months) and evaluated the changes of NYHA. Then the prognostic value of (18)F-FDG PET myocardial metabolism imaging and CCC in patients with CTO lesions were analyzed and evaluated. Results: As the standard evaluation of NYHA in patients with CTO lesions after 12-20 months, fifty-three patients were assigned in this study. According to the changes of NYHA, the patients were divided into no progress group and progress group. There were no statistically difference in age, gender, high risk of CTO lesion and drugs in two groups, but there were significant statistical differences in myocardial parameters. LVEF was significantly increased in patients with CTO lesion in no progress group(42.3%±17.2% vs 22.2%±10.4%, P<0.01). The EDV and ESV in no progress group were significantly smaller than patients in progress group.The sensitivity(95.2% vs 75.7%) and specificity(62.8% vs 38.1%) of (18)F-FDG PET myocardial metabolism imaging was much better than CCC in the evaluation of prognosis in patients with CTO lesion. Conclusion: (18)F-FDG PET myocardial metabolism imaging has important role in the prognosis of patient with CTO lesions when compared with CCC.