Optical Coherence Tomography of De Novo Lesions and In-Stent Restenosis in Coronary Saphenous Vein Grafts (OCTOPUS Study)

Ten-year outcomes after percutaneous coronary intervention of in-stent restenosis in saphenous vein grafts

BACKGROUND

Only few data is available for long-term outcomes of patients being treated for in-stent restenosis (ISR) in saphenous vein grafts (SVG).

AIMS

Thus, the aim of this observational, retrospective study was to close this lack of evidence.

METHODS

Between January 2007 and February 2021 a total of 163 patients with 186 ISR lesions located in SVG were treated at two large-volume centers in Munich, Germany. Endpoints of interest were all-cause mortality, target lesion revascularization (TLR) and target vessel myocardial infarction (TVMI). Furthermore, recurrent ISR were assessed. Outcomes are presented as Kaplan-Meier event rates.

RESULTS

Mean age was 72.6 ± 8.6 years, 90.8% were male, 36.8% were diabetics and 42.3% presented an acute coronary syndrome. ISR were treated with DES in 64.0% and with balloon angioplasty (BA) in 36.0%. After 10 years, the rates for all-cause mortality, TVMI and TLR were 58.2%, 15.4%, and 22.6%, respectively. No statistically relevant differences were found between the types of treatment (DES or BA) regarding all-cause mortality (55.7% vs. 63.2%, p = 0.181), TVMI (13.8% vs. 18.6%, p = 0.215) and TLR (21.8% vs. 25.0%, p = 0.764). Median time between first and recurrent ISR was 270.8 days. Recurrent ISR were treated with DES in a comparable proportion as during first ISR (p = 0.075). Independent predictor of TLR is patient age (p = 0.034). The median follow-up duration was 5.1 years (75% CI 2.8; 8.5).

CONCLUSIONS

Clinical event rates after intervention of ISR located in SVG are high without statistically relevant differences regarding the type of treatment. However, further studies are needed.

Multimodality intravascular imaging of bioresorbable vascular scaffolds implanted in vein grafts

INTRODUCTION

There are no data presenting a serial assessment of vein graft healing after bioresorbable vascular scaffold (BVS) implantation at long-term follow-up.

AIM

To describe ABSORB BVS healing in vein grafts by optical coherence tomography (OCT) and high-definition intravascular imaging (HD-IVUS) at long-term follow-up.Material and methods: The study group consisted of 6 patients. The first patient had serial OCT assessment of BVS implanted in the saphenous vein grafts (SVG) at baseline and at 3-, 6-, 18-month follow-up and the second patient had OCT assessment of BVS implanted in the SVG at baseline and 24-, 48-month follow-up. The second and the third patients had OCT and HD-IVUS imaging at baseline and 48-month follow-up. The last 3 patients had OCT imaging of BVS implanted in the native coronary artery at 48-month follow-up.

RESULTS

There were no differences in neointimal hyperplasia after BVS implantation between each time point. However, complete scaffold coverage was observed only 48 months after implantation. Out of 202 analyzed scaffold struts, there were 67 (33%) black boxes detectable at 48-month follow-up. HD-IVUS presented plaque burden up to 67% at the segment of BVS implantation at 48-months follow-up. There was a difference in neointimal hyperplasia thickness (1.27 (0.953-1.696) vs. 0.757 (0.633-0.848), p < 0.001) between a native coronary artery and BVS scaffolds at 48-month follow-up.

CONCLUSIONS

Bioresorbable vascular scaffold implanted in SVG characterized moderate neointimal hyperplasia as excessive as compared to native coronary arteries at long-term follow-up. The complete scaffold coverage was observed only 48 months after implantation.

Prediction models for different plaque morphology in non-significantly stenosed regions of saphenous vein grafts assessed with optical coherence tomography

Introduction

Coronary artery bypass grafting (CABG) is a method of choice in treatment of diffuse coronary artery disease (CAD), although it has some limitations such as late saphenous vein graft (SVG) patency loss, which occurs in one fifth of all conduits at 5 years. Since atherosclerosis in SVG has diffuse characteristics, it appears that significantly and non-significantly stenosed lesions may have an equal impact on worse prognosis.

Aim

To assess non-significant lesions of SVG by the use of optical coherence tomography (OCT) and investigate the clinical and laboratory findings with the potential impact on plaque composition.

Material and methods

Twenty-nine patients with 43 non-significant lesions were enrolled in the study. All variables were assessed using uni- and multivariable logistic regression analysis with each plaque morphology as a dependent variable. Odds ratio (OR) and 95% confidence interval (CI) were computed.

Results

Plaque rupture (PRT) was independently associated with age (OR = 1.49, 95% CI: 1.09–2.04, p = 0.015) and lower rates of high-density lipoproteins (HDL) cholesterol (OR = 0.67, 95% CI: 0.49–0.92, p = 0.016). Intimal tearing or rupture (ITR) was related to reduced GFR (OR = 0.52, 95% CI: 0.38–0.72, p = 0.0004). Lipid-rich plaque (LRP) was associated with raised platelet count (PLT) (OR = 1.51, 95% CI: 1.16–1.96, p = 0.004) and increased frequency of smoking (OR = 1.45, 95% CI: 1.12–1.89, p = 0.007).

Conclusions

Atherosclerosis of SVG is not restricted to significantly stenosed lesions. Plaque composition is independently associated with different types of clinical and laboratory findings, mostly recognized as risk factors of CAD.

Saphenous graft atherosclerosis as assessed by optical coherence tomography data for stenotic and non-stenotic lesions from the OCTOPUS registry

Introduction

Coronary artery bypass grafting (CABG), although widely used for a long time in diffuse coronary artery disease (CAD), has serious limitations associated with graft aging and its degeneration.

Aim

The relationship between saphenous vein graft (SVG) plaque morphology assessed by optical coherence tomography (OCT) and clinical findings has not been elucidated yet.

Material and methods

We compared the morphology of SVG in stenotic vs. non-stenotic lesions using OCT imaging in 29 patients hospitalized in our center within the OCTOPUS registry.

Results

Stenotic lesions were characterized by higher incidence of thin-cap fibroatheroma (TCFA) (33% vs. 0%, p = 0.0048), thrombus (28% vs. 0%, p = 0.0008), lipid-rich plaque (LRP) (75% vs. 35%, p = 0.0013) and plaque within the SVG valve (19% vs. 0%, p = 0.0114) as compared to non-stenotic lesions. Patients with intimal tearing or rupture (ITR) were older (75.8% vs. 68.9 years, p = 0.047) and had lower left ventricular ejection fraction (LVEF) (32.0% vs. 49.7%, p = 0.001) and glomerular filtration rate (GFR) (36.0 vs. 73.6 ml/min/1.73 m², p = 0.010). Patients with calcified lesions vs. those without had lower high-density lipoprotein (HDL) cholesterol (33.2 vs. 44.1 mg/dl, p = 0.018), similarly to those with ruptured plaque vs. those without (28.3 vs. 41.7 mg/dl, p = 0.047).

Conclusions

Presence of ITR was associated with advanced age, decreased LVEF and renal insufficiency. Decreased concentration of HDL was associated with higher occurrence of calcified and ruptured plaque.