Radial artery as a conduit for coronary artery bypass grafting: a state-of-the-art primer

Long-term consequences of transradial catheterization on the radial artery

BACKGROUND

The radial artery (RA) is often utilized for diagnostic coronary angiography and percutaneous intervention. Recent high-level evidence supports RA use in preference to the saphenous vein as a conduit for coronary revascularization.

AIM

To demonstrate gross and histologic changes of the RA following transradial (TR) access.

METHODS

We present two patients who had open RA harvest for coronary bypass surgery after TR catheterization.

RESULTS

Examination 8 years after TR catheterization demonstrated thickened intima and dissection, and examination 12 years following TR catheterization with percutaneous coronary intervention demonstrated chronic dissection with thickened intima and near occlusion of the lumen.

CONCLUSION

TR access via the RA, even after several years, is associated with significant injury, making it unusable as a conduit for surgical coronary revascularization. A RA that has been utilized for catheterization should not be considered for coronary revascularization.

The RADial artery International ALliance (RADIAL) extended follow-up study: rationale and study protocol

It is generally accepted that radial artery (RA) grafts have better mid-term patency rate compared to saphenous vein grafts. However, the clinical correlates of the improved patency rate are still debated. Observational studies have suggested increased survival and event-free survival for patients who receive an RA rather than a saphenous vein, but they are open to bias and confounders. The only evidence based on randomized data is a pooled meta-analysis of 6 randomized controlled trial comparing the RA and the saphenous vein published by the RADial artery International Alliance (RADIAL). In the RADIAL database, improved freedom from follow-up cardiac events (death, myocardial infarction and repeat revascularization) was found at 5-year follow-up in the RA arm. The most important limitation of the RADIAL analysis is that most of the included trials had an angiographic follow-up in the first 5 years and it is unclear whether the rate of repeat revascularization (the main driver of the composite outcome) was clinically indicated due to per-protocol angiographies. Here, we present the protocol for the long-term analysis of the RADIAL database. By extending the follow-up beyond the 5th postoperative year (all trials except 1 did not have angiographic follow-up beyond 5 years), we aim to provide data on the role of RA in coronary artery bypass surgery with respect to long-term outcomes.

Right internal thoracic or radial artery as the second arterial conduit for coronary artery bypass surgery

PURPOSE OF REVIEW

To summarize the available evidence on the use of the right internal thoracic artery (RITA) and the radial artery as the second arterial graft in coronary artery bypass surgery.

RECENT FINDINGS

The current data support the equipoise of the two conduits in terms of clinical and angiographic outcomes. Both RITA and radial artery have better patency than saphenous vein grafts. The use of the RITA carries an increased risk of deep sternal wound infection (DSWI) if the artery is harvested as pedicle. Bilateral internal thoracic artery grafting is more technically demanding than radial artery use and there is a volume-outcome relationship in terms of mortality and incidence of DSWI. The radial artery is preferable over RITA in right-sided or distal circumflex artery targets with high-degree stenosis and in patients at higher risk for DSWI, whereas it is not recommended to graft vessels with moderate stenosis and in cases of insufficient collateralization from the ulnar artery or previous transradial procedures.

SUMMARY

The patency rate and clinical outcomes of radial artery and RITA are similar. The use of one or the other should be based on a careful evaluation of the patient's coronary anatomy and comorbidities, the conduit availability and the surgeon's and center's experience.