Endoscopic versus open radial artery harvesting: A meta-analysis of randomized controlled and propensity matched studies

Rationale and design of a single-center randomized trial to compare the graft patency between the radial artery and the no-touch saphenous vein in coronary artery bypass grafting surgery (GRAFT-CAB Study)

BACKGROUND

Previous studies suggested only the radial artery and the No-touch (NT) technique were effective in reducing graft occlusion after coronary artery bypass grafting (CABG) surgery. However, there is no randomized trial comparing these 2 graft conduits. The optimum second conduit for CABG remains undetermined.

MATERIALS AND METHODS

This study is a prospective, single-center randomized clinical trial, aiming to compare the graft patency between the radial artery and the NT vein graft. All patients undergoing isolated CABG with left internal mammary artery (LIMA) plus at least 2 additional grafts will be considered eligible. About 774 cases (516 in the radial artery group and 258 in the NT vein group) will be enrolled in over 1 to 2 years. Participants will be randomized and allocated to two bypass strategies: the LIMA plus 1 radial artery and 1 conventional vein graft, or the LIMA plus 2 NT vein grafts. The primary outcome is graft occlusion at 1 year after CABG evaluated by CT angiography. The secondary outcomes include graft occlusion at 3 and 5 years and major adverse cardiac or cerebrovascular events at 1, 3, and 5 years follow-ups.

DISCUSSION

This study will define whether or not the NT vein has a lower graft occlusion rate than the radial artery in short and mid-term follow-ups, and provide new evidence for the second conduit choice in CABG surgery.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06014047. Registered on October 15th, 2023.

Radial artery or saphenous vein for Coronary artery bypass grafitng

Coronary artery disease (CAD) is the most common cardiovascular disease worldwide, affecting over 18 million American adults. Coronary artery bypass grafting (CABG) is the standard of care for patients with left main or triple vessel CAD. Historically, the saphenous vein (SV) has been utilized to bypass the majority of the coronary vessels in patients undergoing CABG, but more recent data suggest that the use of the radial artery (RA), rather than the SV, is associated with improved cardiac outcomes and better survival. The aim of this review is to summarize the current literature on the use of RA and SV for CABG in patients with multivessel CAD.

In patients undergoing coronary artery bypass grafting, is endoscopic harvesting superior to open radial artery harvesting?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'In patients undergoing coronary artery bypass grafting, is endoscopic radial artery harvesting (ERAH) superior to open radial artery harvesting in terms of postoperative complications, mortality, graft quality and patency rates?'. Altogether 130 papers were found using the reported search, of which 5 represented the best evidence to answer the clinical question. Two studies were meta-analyses and 3 were randomized trials. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. In terms of graft quality, 2 randomized studies showed preserved endothelial integrity and vasoreactivity with ERAH, whereas 1 randomized study found superior endothelial function with open radial artery harvesting. Importantly, 3 studies showed graft patency was not compromised with ERAH. One meta-analysis reported no differences in graft patency between groups at 1 year [odds ratio (OR) 1.24] and up to 3-5-years follow-up (OR 1.81), as well as similar perioperative myocardial infarction rates (OR 0.80). Two meta-analyses found similar mortality in the perioperative period (OR 0.62-0.78) and up to 5 years (OR 0.64-0.67); ERAH reduced the incidence of perioperative wound complications (P-values 0.001-0.03); however, harvest times were increased with ERAH (P < 0.0005). We conclude that ERAH is non-inferior to open radial artery harvesting in terms of mortality, graft quality and patency rates, but superior in terms of reducing perioperative wound complications, with good cosmetic effect. However, these benefits come at the cost of increased harvesting time.

Comparative efficacy of autologous versus cadaveric saphenous vein grafts in cerebral revascularization surgery

OBJECTIVE

Cerebral bypasses are performed for the purpose of either flow augmentation for ischemic cerebrovascular disease or flow replacement for vessel sacrifice during complex aneurysm or tumor surgery. Saphenous vein grafts (SVGs) are commonly used interposition grafts. The authors of this study sought to compare the efficacy of autologous versus cadaveric SVGs in a large series of cerebral bypasses using interposition vein grafts with long-term angiographic follow-up.

METHODS

All intracranial bypass procedures performed between 2001 and 2018 were reviewed. Demographic, clinical, angiographic, and operative data were recorded and then analyzed according to SVG type.

RESULTS

A total of 308 consecutive intracranial bypasses were performed during the study period, 53 (17.2%) of which were bypasses with an interposition SVG (38 autologous, 15 cadaveric). At a median follow-up of 2.2 months (IQR 0.2–29.1), 39 (73.6%) bypasses were patent (26 [68.4%] autologous, 13 [86.7%] cadaveric, p = 0.30). Comparing autologous and cadaveric SVG recipients, there were no statistically significant differences in age (p = 0.50), sex (p > 0.99), history of smoking (p = 0.75), hypertension (p > 0.99), diabetes mellitus (p = 0.13), indication for bypass (p = 0.27), or SVG diameter (p = 0.65). While there were higher intraoperative (autologous, 100.0 ml/min, IQR 84.3–147.5; cadaveric, 80.0 ml/min, IQR 47.3–107.8; p = 0.11) and postoperative (autologous, 142.2 ml/min, IQR 76.8–160.8; cadaveric, 92.0 ml/min, IQR 69.2–132.2; p = 0.42) volumetric flow rates in the autologous SVGs compared to those in the cadaveric SVGs, the difference between the two groups did not reach statistical significance. In addition, the blood flow index, or ratio of postoperative to intraoperative blood flow, for each bypass was similar between the groups (autologous, 1.3, IQR 0.9–1.6; cadaveric, 1.5, IQR 1.0–2.3; p = 0.37). Kaplan-Meier estimates showed no difference in bypass patency rates over time between autologous and cadaveric SVGs (p = 0.58).

CONCLUSIONS

Cadaveric SVGs are a reasonable interposition graft option in cerebral revascularization surgery when autologous grafts are not available.

Radial artery harvesting in coronary artery bypass grafting surgery-Endoscopic or open method? A meta-analysis

We analyzed the clinical outcomes of open radial artery harvesting (OAH) and endoscopic radial artery harvesting (EAH) undergoing coronary artery bypass grafting (CABG). We designed this meta-analysis conducted using Pubmed, Medline, the Cochrane Library, and EMBASE. Articles with comparisons of OAH and EAH undergoing CABG were included. Primary outcomes included the wound infection rate, the wound complication rate, neurological complications of the forearm, in-hospital mortality, long-term survival, and the patency rate. The results of our study included six randomized controlled trials (RCTs), two non-randomized controlled trials (NRCTs) with matching, and 10 NRCTs. In total, 2919 patients were included in 18 studies, while 1187 (40.7%) and 1732 (59.3%) patients received EAH and OAH, respectively. EAH was associated with a lower incidence of wound infection (RR = 0.29, 95% confidence interval (CI) = 0.14 to 0.60, p = 0.03), and neurological complications over the harvesting site (RR = 0.41, 95% CI = 0.27 to 0.62, p < 0.0001). There was no significant difference in 30-day mortality, long-term survival (over one year), and the graft patency rate. According to our analysis, endoscopic radial artery harvesting can improve the outcome of the harvesting site, without affecting the mortality, long-term survival, and graft patency.

Prospective randomized trial of endoscopic vs open radial artery harvest for CABG: Clinical outcome, patient satisfaction, and midterm RA graft patency

BACKGROUND AND AIM

Endoscopic radial artery (RA) harvest (ERAH) is an alternative to open RA harvest (ORAH) technique. Our aim was to ascertain clinical outcomes, patent satisfaction, and 1-year angiographic patency rates after ERAH and ORAH.

PATIENTS AND METHODS

A total of 50 patients undergoing coronary artery bypass grafting were prospectively randomized to two groups. In the ERAH group (25 patients) the RA was harvested endoscopically and in the ORAH group (25 patients) openly.

RESULTS

There were not differences between the groups in preoperative characteristics. Length of skin incision was shorter in ERAH (P < .001) but there were not differences in the length of RA, harvest time, blood flow, and pulsatility index after ERAH and ORAH. Wound healing was uniformly smooth in ERAH and there were two hematomas and one infection in ORAH. Postoperatively, major neuralgias were present in five patients in ORAH and none in ERAH and minor neuralgias in 11 and 3 patients (P = .02) respectively. Twenty-four patients in ERAH and four in ORAH graded their experience as excellent (P < .001). One-year angiographic RA patency was 90% without intergroup difference. Target vessel stenosis less than 90% adversely affected RA patency (P < .0001).

CONCLUSIONS

In expert center, ERAH does not appear to have negative impact on the time harvest, the length, and quality of RA conduit, the wound healing, and the occurrence of hand and forearm complications. In addition, provides excellent cosmetic result and patient satisfaction. RA graft patency is gratifying when placed to a target coronary artery vessel with stenosis greater than 90%.

Open radial artery harvesting better preserves endothelial function compared to the endoscopic approach

OBJECTIVES

Both the open and endovascular techniques are commonly used for harvesting the radial artery (ORAH and ERAH, respectively), and yet, very little is known about the effects of these 2 techniques on endothelial integrity and function of the radial artery (RA). The aim of this study was to assess the endothelial integrity and function of RA harvested using the 2 approaches.

METHODS

Two independent surgical teams working in the same institution routinely use the RA for coronary artery bypass grafting exclusively employing either ORAH or ERAH. Thirty-nine consecutive patients were enrolled in this comparative study. Endothelial function after ORAH or ERAH was assessed by using the wire myograph system. The integrity of the RA endothelium was evaluated by immunohistochemical staining for erythroblast transformation specific-related gene.

RESULTS

The vasodilation in response to acetylcholine was significantly higher in RA harvested with ORAH (P ≤ 0.001 versus ERAH). Endothelial integrity was not different between the 2 groups.

CONCLUSIONS

ORAH is associated with a significantly higher endothelium-dependent vasodilation. Further investigation on the potential implications of these findings in terms of graft spasm and patency as well as clinical outcomes are needed.

Technical Aspects of the Use of the Radial Artery in Coronary Artery Bypass Surgery

BACKGROUND

The radial artery has been used for coronary artery bypass surgery for more than 25 years. The recent confirmation of the clinical benefits associated with the use of the artery is likely to drive a new interest toward this conduit in the next few years.

METHODS

A group of surgeons with extensive experience in the systematic use of the radial artery summarize here the key technical aspects of the use of the conduit for coronary bypass operations.

RESULTS

Preoperative evaluation of the ulnar collateral circulation and attention to the characteristics of the target vessel are keys for the successful use of the radial artery. Open or endoscopic harvesting can be used, preferentially with the aid of the harmonic scalpel. The use of vasodilatory and antispastic protocols is probably important but poorly supported by the current evidence. The radial artery can be used for multiple grafting strategies with a variable degree of technical complexity.

CONCLUSIONS

With attention to few technical key points, the radial artery is a versatile conduit that can be easily introduced in the everyday practice of coronary artery bypass surgery.

Optimal management of radial artery grafts in CABG: Patient and target vessel selection and anti-spasm therapy

The current literature on radial artery grafting is reviewed focusing on the optimal deployment of radial artery grafts in coronary artery bypass surgery with specific attention to the selection of patients and target vessels for radial artery grafting.