Clinical outcomes and quality of life after contemporary isolated coronary bypass grafting: a prospective cohort study

OBJECTIVES

The objective of the European Multicenter Registry to Assess Outcomes in coronary artery bypass grafting (CABG) patients (DuraGraft Registry) was to determine clinical outcomes and quality of life (QoL) after contemporary CABG that included isolated CABG and combined CABG/valve procedures, using an endothelial damage inhibitor (DuraGraft) intraoperatively for conduit preservation. Here, we report outcomes in the patient cohort undergoing isolated CABG.

METHODS

The primary outcome was the composite of all-cause death, myocardial infarction (MI), or repeat revascularization (RR) [major adverse cardiac events (MACE)] at 1 year. Secondary outcomes included the composite of all-cause death, MI, RR, or stroke [major adverse cardiac and cerebrovascular events (MACCE)], and QoL. QoL was assessed with the EuroQol-5 Dimension questionnaire. Independent risk factors for MACE at 1 year were determined using Cox regression analysis.

RESULTS

A total of 2532 patients (mean age, 67.4±9.2 years; 82.5% male) underwent isolated CABG. The median EuroScore II was 1.4 [interquartile range (IQR), 0.9-2.3]. MACE and MACCE rates at 1 year were 6.6% and 7.8%, respectively. The rates of all-cause death, MI, RR, and stroke were 4.4, 2.0, 2.2, and 1.9%, respectively. The 30-day mortality rate was 2.3%. Age, extracardiac arteriopathy, left ventricular ejection fraction less than 50%, critical operative state, and left main disease were independent risk factors for MACE. QoL index values improved from 0.84 [IQR, 0.72-0.92] at baseline to 0.92 [IQR, 0.82-1.00] at 1 year ( P <0.0001).

CONCLUSION

Contemporary European patients undergoing isolated CABG have a low 1-year clinical event rate and an improved QoL.

Clinical event rate in patients with and without left main disease undergoing isolated CABG: results from the European DuraGraft registry

OBJECTIVES

Left main coronary artery disease (LMCAD) is considered an independent risk factor for clinical events after coronary artery bypass grafting (CABG). We have conducted a subgroup analysis of the multicentre European DuraGraft registry to investigate clinical event-rates at 1-year in patients with and without LMCAD undergoing isolated CABG in contemporary practice.

METHODS

Patients undergoing isolated CABG were selected. The primary end-point was the incidence of a major adverse cardiac event (MACE) defined as the composite of death, myocardial infarction (MI) or repeat revascularization (RR) at 1-year. The secondary end-point was major adverse cardiac and cerebrovascular events (MACCE) defined as MACE plus stroke. Propensity score matching (PSM) was performed to balance for differences in baseline characteristics.

RESULTS

LMCAD was present in 1,033 (41.2%) and absent in 1,477 (58.8%) patients. At 1-year, the MACE rate was higher for LMCAD patients (8.2% vs 5.1%, p = 0.002) driven by higher rates of death (5.4% vs 3.4%, p = 0.016), MI (3.0% vs 1.3%, p = 0.002) and numerically higher rates of RR (2.8% vs 1.8%, p = 0.13). The incidence of MACCE was 8.8% vs 6.6%, p = 0.043 with a stroke rate of 1.0% and 2.4%, p = 0.011, for LMCAD and non-LMCAD group, respectively. After PSM, the MACE rate was 8.0% vs 5.2%, p = 0.015. The incidence of death was 5.1% vs 3.7%, p = 0.10, MI 3.0% vs 1.4%, p = 0.020, and RR was 2.7% vs 1.6%, p = 0.090, for the LMCAD and non-LMCAD group, respectively. Less strokes occurred in LMCAD patients (1.0% vs 2.4%, p = 0.017). The MACCE rate was not different: 8.5% vs 6.7%, p = 0.12.

CONCLUSIONS

In this large registry, LMCAD was demonstrated to be an independent risk factor for MACE after isolated CABG. Conversely, the risk of stroke was lower in LMCAD patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02922088.

A Novel Endothelial Damage Inhibitor Reduces Oxidative Stress and Improves Cellular Integrity in Radial Artery Grafts for Coronary Artery Bypass

The radial artery (RA) is a frequently used conduit in coronary artery bypass grafting (CABG). Endothelial injury incurred during graft harvesting promotes oxidative damage, which leads to graft disease and graft failure. We evaluated the protective effect of DuraGraft®, an endothelial damage inhibitor (EDI), on RA grafts. We further compared the protective effect of the EDI between RA grafts and saphenous vein grafts (SVG). Samples of RA (n = 10) and SVG (n = 13) from 23 patients undergoing CABG were flushed and preserved with either EDI or heparinized Ringer's lactate solution (RL). The effect of EDI vs. RL on endothelial damage was evaluated ex vivo and in vitro using histological analysis, immunofluorescence staining, Western blot, and scanning electron microscopy. EDI-treated RA grafts showed a significant reduction of endothelial and sub-endothelial damage. Lower level of reactive oxygen species (ROS) after EDI treatment was correlated with a reduction of hypoxic damage (eNOS and Caveolin-1) and significant increase of oxidation-reduction potential. Additionally, an increased expression of TGFβ, PDGFα/β, and HO-1 which are indicative for vascular protective function were observed after EDI exposure. EDI treatment preserves functionality and integrity of endothelial and intimal cells. Therefore, EDI may have the potential to reduce the occurrence of graft disease and failure in RA grafts in patients undergoing CABG.

Sequential multidetector computed tomography assessments after venous graft treatment solution in coronary artery bypass grafting

OBJECTIVES

To assess the effect of DuraGraft (Somahlution Inc, Jupiter, Fla), an intraoperative graft treatment, on saphenous vein grafts in patients undergoing isolated coronary artery bypass grafting.

METHODS

Within patients, 2 saphenous vein grafts were randomized to DuraGraft or heparinized saline. Multidetector computed tomography angiography at 1, 3, and 12 months assessed change in wall thickness (primary end point at 3 months), lumen diameter, and maximum narrowing for the whole graft and the proximal 5-cm segment. Safety end points included graft occlusion, death, myocardial infarction, and repeat revascularization.

RESULTS

At 3 months, no significant changes were observed between DuraGraft- and saline-treated grafts (125 each) for wall thickness, lumen diameter, and maximum narrowing. At 12 months, DuraGraft-treated grafts demonstrated smaller mean wall thickness, overall (0.12 ± 0.06 vs 0.20 ± 0.31 mm; P = .02) and in the proximal segment (0.11 ± 0.03 vs 0.21 ± 0.33 mm; P = .01). Changes in wall thickness were greater in the proximal segment of saline-treated grafts (0.09 ± 0.29 vs 0.00 ± 0.03 mm; P = .04). Increase in maximum graft narrowing was larger in the proximal segment in the saline-treated grafts (4.7% ± 12.7% vs 0.2% ± 3.8%; P = .01). Nine DuraGraft and 11 saline grafts had occluded or thrombosed. One myocardial infarction was associated with a saline graft occlusion. No deaths or revascularizations were observed.

CONCLUSIONS

DuraGraft demonstrated a favorable effect on wall thickness at 12 months, particularly in the proximal segment. Longer-term follow-up in larger studies is needed to evaluate the effect on clinical outcomes.

DuraGraft vascular conduit preservation solution in patients undergoing coronary artery bypass grafting: rationale and design of a within-patient randomised multicentre trial

Introduction

Saphenous vein grafts (SVGs) remain the most often used conduits in coronary artery bypass grafting (CABG). However, they are prone to vein graft disease (VGD) during follow-up, which may compromise clinical outcomes. Injury to the SVG endothelium during harvesting and storage promotes neointimal hyperplasia that can advance to atherosclerosis characterised by SVG failure. This trial investigates the potential benefit of DuraGraft, a novel, one-time intraoperative graft treatment developed to efficiently protect the structural and functional integrity of the vascular endothelium, on the development and progression of VGD in CABG patients.

Methods and analysis

This ongoing prospective randomised, double-blinded multicentre trial (NCT02272582/NCT02774824) includes patients undergoing isolated CABG requiring at least two SVGs. It compares the impact of DuraGraft, a novel treatment against VGD versus the standard-of-care (SOC; heparinised saline) using a within-patient randomisation (with one SVG treated with DuraGraft and the other treated with SOC). Besides clinical assessments, patients undergo longitudinal 64-slice or better multidetector CT (MDCT) angiography of paired grafts (within each patient) at 4–6 weeks, 3 months and 12 months. Primary endpoints will be the magnitude of change in mean wall thickness and lumen diameter (stenosis) of paired grafts, at 3 and 12 months, respectively. Besides the evaluation of overall safety, longitudinal assessment of each graft (secondary endpoint) is performed in order to obtain insight into graft behaviour after CABG. Enrolment of 119 patients was successfully completed, and analysis of MDCT angiography follow-up is ongoing with the completed analysis becoming available by end of first quarter of 2018.

Ethics and dissemination

The regional ethics committees have approved the trial. Results will be submitted for publication.

Clinical trial identifier

NCT02272582 and NCT02774824.