Background:
Percutaneous coronary intervention (PCI) of degenerated saphenous vein grafts (SVGs) remains challenging because of high thrombus burden, distal embolization, and no-reflow. In selected cases, local intracoronary thrombolysis may represent a bailout strategy when conventional PCI techniques are unlikely to achieve a satisfactory result.
Case presentation:
A 68-year-old man presented with crescendo angina for ten days and NSTEMI with previous coronary artery bypass graft surgery. Diagnostic coronary angiography demonstrated a patent LIMA-LAD graft and SVG to the right posterolateral branch, whereas all of the native coronary arteries were chronically occluded. Following successful guidewire crossing, lesion passage was achieved with a 1.25 × 20 mm balloon without inflation.
Despite this, angiography demonstrated persistent extensive thrombotic material throughout the graft with only minimal restoration of antegrade flow. Current guidelines favor PCI of the native coronary artery rather than the saphenous vein graft whenever technically feasible, but do not provide an established role for local intracoronary thrombolysis in this setting. At this stage, several treatment options were discussed, including balloon dilatation and stenting, aspiration thrombectomy, distal protection devices like filter wire, glycoprotein IIb/IIIa inhibition. Because of the substantial thrombus burden, the anticipated risk of distal embolization and no-reflow, and the uncertain benefit of extensive stent implantation in a severely degenerated vein graft, a decision was made to perform local intracoronary thrombolysis.
A Finecross microcatheter was advanced into the thrombotic SVG. Alteplase (20 mg total dose) was administered locally through a microcatheter over approximately 50 minutes from distal to proximal. Unfractionated heparin was administered via the guiding catheter. This strategy was based on historical experiences with catheter-directed thrombolysis in occluded saphenous vein grafts and lesion-directed intracoronary fibrinolysis.
Control angiography demonstrated a marked reduction in thrombus burden and restoration of antegrade flow within the SVG-M2 graft with satisfactory distal runoff. Following thrombus resolution, the residual culprit lesion was treated with implantation of a 3.0 × 20 mm drug-eluting stent, resulting in an excellent final angiographic result with TIMI 3 flow and no evidence of distal embolization or no-reflow. The procedure was completed successfully without further complications.
Discussion:
Degenerated SVG lesions are associated with high rates of distal embolization, no-reflow, and periprocedural myocardial infarction. Although contemporary PCI strategies generally favor embolic protection and stent-based treatment, procedural success may remain limited in the presence of extensive thrombotic burden. In the present case, the lesion could be crossed with a guidewire and small balloon; however, a large residual thrombus burden persisted. Additional balloon dilatation or stenting was considered likely to increase the risk of distal embolization. Therefore, local intracoronary alteplase followed by implantation of a DES was selected as a bailout strategy.
Conclusion:
This case illustrates that catheter-directed intracoronary thrombolysis may provide an alternative strategy when thrombus burden is the dominant mechanism of SVG failure and conventional PCI options are unlikely to achieve an optimal result.
