Graft failure and recurrence of symptoms after coronary artery bypass grafting

Area of Science:

• Cardiovascular Surgery
• Interventional Cardiology
• Vascular Biology

Background:

• Saphenous vein grafts (SVGs) used in coronary artery bypass grafting (CABG) often develop graft disease, leading to poor long-term patency.
• The precise clinical impact of SVG failure on recurrent coronary artery disease (CAD) symptoms remains incompletely understood.

Purpose of the Study:

• To evaluate how SVG graft failure influences the recurrence of CAD symptoms post-CABG.
• To determine the contribution of atherosclerosis progression in native coronary arteries to recurrent CAD symptoms.

Main Methods:

• Analysis of 46,663 CABG cases from the SWEDEHEART registry (2001-2015) in patients aged 40-80 years.
• Comparison of outcomes for single internal mammary artery (IMA) anastomosis, IMA with one SVG (1SVG), and IMA with multiple SVG (2+ SVG) procedures.
• Calculation of multivariable adjusted hazard ratios for mortality and postoperative coronary angiography, with recording of indications and graft failure occurrence.

Main Results:

• Mortality rates were similar across the three surgical groups (IMA, 1SVG, 2+ SVG).
• The adjusted hazard ratio for undergoing angiography was higher for IMA (1.24) and 1SVG (1.21) compared to 2+ SVG.
• Graft failure was identified in 21.4% of IMA, 41.6% of 1SVG, and 61.1% of 2+ SVG patients presenting with CAD symptoms and undergoing initial angiography.

Conclusions:

• A significant proportion of postoperative CAD symptom recurrence and subsequent angiographies occur in patients without detectable graft failure.
• Internal mammary artery (IMA) graft failure or progression of atherosclerosis in native coronary arteries are likely significant contributors to recurrent CAD symptoms.