Disclosures: The authors have no conflicts of interest to report. Funding sources: No grant, contract, or other sources of financial support were used for the creation of this article.

This article received double-blind peer review from members of the Cath Lab Digest editorial board.

The authors can be contacted via Andro G. Kacharava at Atlanta Veterans Affairs Medical Center, Cardiology Division, 1670 Clairmont Road, Room 2A191, Decatur, GA 30033. E-mail akachar@emory.edu.

The procedure of selective cannulation of the left internal mammary artery (LIMA) with coaxial position of the catheter permits high-quality angiography for improved visualization of the arterial graft,anastomosis site, and native coronary artery it supplies. Tortuous left or right subclavian arteries (SA) in patients with previous coronary bypass surgery make selective cannulation of the internal mammary artery (IMA) through the femoral approach very difficult.  We describe a helpful technique to manage this problem when other well-known techniques may fail to provide adequate opacification of the LIMA for diagnostic evaluation.   

Case report

A 74-year-old diabetic man with a history of extensive coronary artery disease and coronary artery bypass graft surgery (CABG) x 4 underwent cardiac catheterization for evaluation of atypical chest pain and a large reversible anterior wall defect on exercise myocardial perfusion imaging. Selective angiography of two saphenous vein grafts and one left radial graft performed through a 5 French (Fr) sheath placed in the right common femoral artery demonstrated mild luminal irregularities. For selective cannulation of the LIMA graft to the left anterior descending coronary artery (LAD), a 5Fr IMA catheter was advanced over a Wholey wire (Covidien) to the aortic arch and maneuvered counterclockwise into the left subclavian artery (LSA) ostium. The 5Fr IMA catheter was advanced through the tortuous LSA over wire to its mid-segment. Several unsuccessful attempts were made to engage the LIMA graft. The anterior takeoff of the LIMA and the tortuosity of the LSA made it difficult to achieve selective engagement of the LIMA ostium with the IMA catheter (Figure 1). To overcome this technical difficulty, the 5Fr IMA catheter was wired with a long, extra stiff 0.035-inch Amplatz wire (Boston Scientific). The distal end of the wire was placed in the axillary artery. The 5Fr IMA catheter was removed, and the 5Fr sheath exchanged over the wire to a 6Fr sheath. Five thousand (5000) units of intravenous (IV) heparin were given and activated clotting time (ACT) was kept at >200 seconds throughout the rest of the procedure. A 4Fr IMA catheter was placed over the Wholey wire through the 6Fr sheath next to the Amplatz extra stiff wire and advanced to the aortic arch.  Subsequently, the 4Fr IMA catheter was maneuvered counterclockwise through the LSA ostium over the Wholey wire and placed in the mid-LSA parallel to the Amplatz extra stiff wire (the Wholey wire was removed) (Figure 2). The Amplatz extra stiff wire provided strong back-up support for the IMA catheter, which was easily navigated into the LIMA ostium, and selective angiography obtained (Figures 3-5). 

As mentioned above, tortuosity of the left or right SA in patients with previous coronary bypass surgery make selective cannulation of the IMA through the femoral approach difficult, especially the ones with an anterior takeoff. Well-known techniques for selective IMA opacification include percutaneous left brachial or radial artery approach, and semi-selective opacification using a balloon catheter or use of specialty catheters, i.e. VB-1 (Cordis Corporation). Non-selective imaging of the vessel in many cases can be dramatically improved by using an external blood pressure cuff on the left arm to temporarily occlude flow of the subclavian artery, or with simple arm abduction, deep inspiration, and head rotation. When the above aforementioned approaches are not possible or fail to produce optimal images of the target vessel, our technique addresses this particular situation by parallel placement of an Amplatz guidewire serving as a stiff rail, and providing strong back-up support for quick and easy maneuvering of the IMA catheter into the target vessel ostium. The efficiency and safety of this method has obviously yet to be proved in a larger series.

References

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