In CABG patients, external graft support devices fail to prolong patency of saphenous vein graft: JAMA
USA: The difference in intimal hyperplasia area between supported and unsupported saphenous vein grafts at 12 months did not achieve statistical significance in in patients undergoing a coronary bypass graft procedure, says a recent study published in JAMA Cardiology.
The study found similar cumulative mortality and major cardiac or cerebrovascular events rates to those in other randomized coronary artery bypass trials. Further investigation is warranted to assess the effect of external graft support devices on long-term graft patency and clinical outcomes
In patients undergoing coronary artery bypass surgery, intimal hyperplasia and subsequent saphenous vein graft failure may have significant adverse clinical effects. External support of saphenous vein grafts may prevent vein graft dilation and hence reduce the rate of intimal hyperplasia and increase long-term vein patency.
Against the above background, Daniel J. Goldstein, Department of Cardiovascular and Thoracic Surgery, Montefiore Medical Center, Bronx, New York, and colleagues aimed to determine efficacy, as measured by intimal hyperplasia, and safety of an external saphenous vein graft support device in patients undergoing a coronary bypass graft procedure.
For this purpose, the researchers conducted a within-patient randomized, open-label, multicenter study at 17 Cardiothoracic Surgical Trials Network centers in North America. 224 patients with multivessel coronary artery disease undergoing isolated bypass surgery were enrolled between January 2018 and February 2019. For each patient, 1 of 2 vein grafts was randomized to receive external support or no support.
Intimal hyperplasia area assessed by intravascular ultrasound at 12 months postrandomization for each study graft was the primary efficacy end point.
Salient findings include:
- Among 224 patients (mean age, 65.8 years; 79.5% male), 90.6% were eligible for intravascular ultrasound, of which 41.9% had at least 1 study graft occluded or severely diseased at 12 months (55 supported, 56 unsupported).
- After imputation of data missing because of graft occlusion or severe disease, the estimated mean intimal hyperplasia area was 5.11 mm2 in supported grafts and 5.79 mm2 in unsupported grafts.
- In a sensitivity analysis of 113 patients with both grafts imaged, the mean intimal hyperplasia area was 4.58 mm2 and 5.12 mm2 in supported and unsupported grafts, respectively.
- By 12 months, 2.2% patients died and 7.1% patients experienced a major cardiac or cerebrovascular event.
The researchers conclude, "further investigation to assess the effect of external graft support devices on long-term graft patency and clinical outcomes is warranted."
Reference:
Goldstein DJ, Puskas JD, Alexander JH, et al. External Support for Saphenous Vein Grafts in Coronary Artery Bypass Surgery: A Randomized Clinical Trial. JAMA Cardiol. Published online June 08, 2022. doi:10.1001/jamacardio.2022.1437
