Quantitative optical coherence tomography analysis for late in-stent restenotic lesions

Prediction of Slow-Flow Phenomenon After Stent Implantation Using Near-Infrared Spectroscopy in Patients With Acute and Chronic Coronary Syndrome

BACKGROUND

The slow-flow phenomenon is associated with worse clinical outcomes after percutaneous coronary intervention (PCI), so our goal for this study was to see how predictive how near-infrared spectroscopy (NIRS) could be.Methods and Results: We enrolled 179 lesions from 152 patients who had de novo coronary stent implantation guided by NIRS-intravascular ultrasound (IVUS) (male: 69.1%, mean age: 74.3±11.5 years, acute coronary syndrome: 65.1%, diabetes: 42.1%). NIRS automatically determined the maximum 4-mm lipid core burden index (maxLCBI4 mm) value at pre- and post-PCI procedures. The slow-flow phenomenon was defined as the deterioration of TIMI (Thrombolysis in Myocardial Infarction) flows on angiography during the PCI procedure in the absence of mechanical obstruction. The slow-flow phenomenon occurred in 13 (7.3%) lesions, and the slow-flow phenomenon group had a significantly higher maxLCBI4 mm(740±147 vs. 471±223, P<0.001). The best maxLCBI4 mmcutoff point in both acute and chronic coronary syndrome was 578 and 480, with sensitivity of 100%, for predicting the slow-flow phenomenon. In the receiver-operating characteristics analysis, the area under the curve for acute and chronic coronary syndrome was 0.849 and 0.851, respectively.

CONCLUSIONS

The results of this study support the utility of NIRS-IVUS-guided PCI for the prediction of the slow-flow phenomenon.

ΔRDW Could Predict Major Adverse Cardiovascular Events in Patients with Heart Failure with Reduced Ejection Fraction After Sacubitril/Valsartan Treatment

Objective

This study aimed to evaluate the association between red blood cell distribution width (RDW) changes and major adverse cardiovascular event (MACE) occurrences during sacubitril/valsartan treatment in patients with heart failure with reduced ejection fraction (HFrEF).

Methods

This study retrospectively analyzed the medical records of patients with HFrEF hospitalized from April 2018 to February 2021. The patients were divided into two groups according to the inclusion of sacubitril/valsartan in the personal drug treatment regimen, the traditional and the sacubitril/valsartan group. RDW values before and after sacubitril/valsartan treatment were recorded respectively as RDW1 and RDW2. ΔRDW was defined as the difference between RDW2 and RDW1. The patients in the sacubitril/valsartan group were divided into two subgroups according to ΔRDW >0 or ≤0. MACEs, such as readmission for HF, acute myocardial infarction, ischemic stroke, and malignant arrhythmia and death, were recorded during the 1-year follow-up period in each group.

Results

MACE development was lower in patients treated with sacubitril/valsartan than those treated with conventional therapy (log-rank, P<0.001). The incidence of cardiac events during the follow-up period was greater in the group with ΔRDW >0 than in the group with ΔRDW ≤0 (Breslow, P<0.001). Increased RDW was associated with a higher likelihood of developing MACE than decreased RDW (odds ratio [OR] =2.055, 95% confidence interval [CI]:1.301-3.246), and the risk of developing MACE increased by 22.1% for each unit increase in RDW (OR=1.221, 95% CI:1.074-1.389).

Conclusion

Sacubitril/valsartan treatment is effective in reducing the risk of MACEs in HFrEF. Additionally, RDW changes are predictors of MACEs after sacubitril/valsartan treatment.

Vascular response profiles following a nano polymer-free sirolimus-eluting stent implantation assessed by optical coherence tomography in a porcine model

Optical coherence tomography (OCT) is a high resolution imaging modality and has been considered as the ideal tool for the evaluation of neointimal tissue and vascular responses following stent implantation. However, vascular response profiles following the implantation of a novel nano polymer-free sirolimus-eluting stent (SES) assessed by OCT has not been fully investigated. Therefore, the aim of the present study was to determine the effects of a nano polymer-free SES on neointimal formation using OCT. A total of 16 nano polymer-free SESs were implanted in the coronary arteries of 8 pigs. At 3 (n=4) or 6 months (n=4), the animals were euthanized following OCT evaluation and the stented arterial segments were analyzed by histological analysis. Neointimal area, thickness and burden were evaluated by OCT. In addition, strut-associated inflammation, stent endothelialization and arterial injury were investigated by histomorphological analysis. OCT examination showed that at 6 months, neointimal thickness (193.3±109.5 vs. 167.2±119.7 µm, P=0.023) and neointimal burden (29.3±14.3 vs. 24.8±17.4%, P=0.006) significantly increased compared with at 3 months. Histomorphological analysis indicated that the endothelialization score was significantly greater at 6 months compared with at 3 months (2.85±0.36 vs. 2.52±0.60, P<0.001). However, at 3 months, nano polymer-free SES showed a significantly higher inflammatory score [0 (0, 1) vs. 0 (0, 0), P<0.001] compared with at 6 months. In conclusion, nano polymer-free SES achieves endothelialization at 3 months; however, neointimal proliferation is more significant at 6 months and may be attributed to strut-associated inflammation.

Three-Year Clinical and Angiographic Outcomes After Everolimus-Eluting Stent Implantation in Patients With a History of Coronary Artery Bypass Grafting

The clinical and angiographic outcomes after percutaneous coronary intervention (PCI) with everolimus-eluting stent (EES) implantation in patients with a history of coronary artery bypass grafting (CABG) have yet to be fully investigated. The aim of the present study was to investigate 3-year clinical outcomes after EES implantation in patients with a history of CABG.We retrospectively enrolled 176 consecutive patients who had undergone EES implantation. Three-year clinical follow-up data were obtained from all patients. Follow-up angiograms and serial quantitative coronary angiography analysis (QCA) were performed for 139 (79.0%) patients. Patients from the prior CABG (+) group (n = 17; 9.7%) had higher incidences of target lesion revascularization (TLR; 41.2% versus 3.8%, P < 0.001) and major adverse cardiac events (47.1% versus 15.1%, P = 0.004). A landmark analysis conducted 1 year into our study showed a higher incidence of TLR in the prior CABG (+) group (20.0% versus 3.0%, P = 0.017).The reason for EES implantation in the prior CABG (+) group was saphenous vein graft (SVG) failure in 19 (79.2%) lesions, although the target vessel was the SVG in 8 (33.3%) lesions. There were no significant differences in clinical and follow-up QCA data between the native vessel and SVG PCI groups.This study revealed that a history of CABG was a risk factor for TLR after EES implantation. The major reason for PCI after CABG was SVG failure; both native vessel and SVG PCI showed poor outcomes. Further investigations may be warranted to determine which interventions are most effective in this high-risk subset.

The clinical characteristics and prognosis of lesions with in-stent eccentric tissue proliferation and strong signal attenuation detected by optical coherence tomography

There are still some patients who require repeat revascularization despite of drug-eluting stent (DES) implantation. The present study aimed to investigate the relationship between optical coherence tomography (OCT) findings and recurring target lesion revascularization (TLR) after percutaneous coronary intervention (PCI) for in-stent restenosis (ISR). We reviewed 50 patients (54 coronary lesions) who underwent PCI for ISR, which included 25 DES-ISR lesions. The PCI strategy depended on the interventionalist's discretion, and DES implantation was performed for 38 (70 %) lesions. Tissue characteristics were assessed qualitatively and quantitatively using the frame showing maximal lumen narrowing (minimal lumen area). In qualitative analysis, OCT detected coexistence of eccentric tissue proliferation and strong signal attenuation (ESA). ESA was observed in six lesions (11 %) in five patients (10 %). Hemodialysis (80 vs. 20 %, p = 0.013) and DES-ISR (100 vs. 40 %, p = 0.0069) were significantly more frequent in ESA patients/lesions than in others. One-year follow-up revealed that re-TLR was more frequently performed for ESA lesions (83 vs. 8 %, p = 0.0002). The findings reveal that ESA detected in OCT images of ISR is related to TLR after PCI for DES-ISR especially in patients undergoing maintenance hemodialysis.

Early Phase Arterial Reaction Following Drug-Eluting and Bare-Metal Stent Implantation in Patients With ST-Segment Elevation Myocardial Infarction

The early phase arterial reaction after implantation of second-generation drug-eluting stents (2nd DES) and baremetal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) remains unclear.The MECHANISM pilot study is a multi-center prospective registry that enrolled 24 STEMI patients (from 11 centers) who had undergone implantation of everolimus-eluting (n = 6), biolimus A9-eluting (n = 6) or zotarolimus-eluting stents (n = 6), or BMS (n = 6). Scheduled optical coherence tomography (OCT) was performed 2 weeks after implantation, and images were independently analyzed at a core laboratory in a blinded fashion. Intra-stent thrombus was quantitatively analyzed in terms of the maximal area and the percentage of cross-sections with thrombus (the numbers of cross-section with thrombus × 100 divided by total number of cross-sections within the stented segment). More than 90% of struts were already covered 2 weeks after the index procedure, regardless of the stent type. There were no differences in stent diameter, minimal lumen diameter, minimal lumen area, neointimal thickness, or the frequencies of malapposed and uncovered struts among the 4 groups. The quantity of intra-stent thrombus also did not differ among the 4 groups.The results of this pilot study suggest that the 2-week vascular responses seem to be similar among 2nd DES and BMS in STEMI patients. Considering the possible advantage of 2nd DES in the prevention of restenosis, 2nd DES are a feasible option for the treatment of patients with STEMI.