Abstract
This case illustrates the potential clinical usefulness of retrograde approach for selective visualization of distal vessels in a patient with multiple coronary chronic total occlusions and previous coronary artery bypass graft (CABG) surgery. By knowing in extreme detail the exact anatomy of the complex post-surgical coronary system, a successful treatment can be planned for the patient.
This case illustrates the potential clinical usefulness of retrograde approach for selective visualization of distal vessels in a patient with multiple coronary chronic total occlusions and previous coronary artery bypass graft (CABG) surgery. By knowing in extreme detail the exact anatomy of the complex post-surgical coronary system, a successful treatment can be planned for the patient. A 60-year-old man had out-of-hospital cardiac arrest due to ventricular fibrillation in 2007. His neurological recovery was good. His coronary angiogram showed three vessel disease with reasonable rest left ventricular function; CABG was done with a free left internal mammary artery (LIMA) and right internal mammary artery (RIMA) Y-graft to the left anterior descending (LAD) artery and obtuse marginal (OM) artery respectively, and a saphenous vein graft (SVG) to the right posterior descending artery. In 2012 the patient had recurrent out-of-hospital cardiac arrest. An implantable cardioverter–defibrillator was implanted. A new coronary angiogram ( Fig. 1 ) showed occlusion of the mid right coronary artery, proximal circumflex and proximal LAD with scanty collaterals to the mid-distal LAD. The SVG to right posterior descending artery was patent and collaterals to the OM branch were noticed. The free LIMA–RIMA Y-graft was impossible to engage selectively and was deemed as occluded, as collaterals for both the LAD and the OM were visible. Repeated antegrade attempts to recanalize the occluded LAD were unsuccessful. In an attempt to recanalize via retrograde approach the LAD from the SVG to the right coronary artery, the wire and the retrograde micro-catheter were advanced by chance in the OM branch without any resistance. The selective retrograde injection via the micro-catheter showed a patent Y bifurcation graft open to distal LAD and OM but with a clear occlusive stump at the level of the proximal anastomosis of the graft to the ascending aorta. The graft system could only be visualized in this way and careful review of previous angiograms did not reveal any opacification of this graft itself. So the patient in fact had an occlusion of the ostial LIMA graft only and the distal part of graft system was still patent and possibly well-functioning, but it was too distal to be visualized by “standard” coronary angiogram. After detailed discussion with the cardiothoracic surgeons, a repeated CABG was planned. By knowing the detailed anatomy, an off-pump minimally invasive procedure was planned with a radial graft on the LIMA arm of the old LIMA–RIMA Y-graft. This type of procedure would have been impossible without clear visualization of the patency of the Y-graft. The operation was successful, and the patient had a good and quick recovery. A repeated angiogram 3 months after surgery showed a patent radial graft to the LIMA–RIMA Y-graft and good coronary flow to the LAD and the OM. Retrograde wiring of vessels/bypasses that are not clearly visible with routine antegrade injections can be also useful to detect not only closed bypasses (such as in our case) but also bypasses located in unusual positions . Furthermore, a possible alternative solution to assess a complex post-CABG anatomy can be a multiscan computed tomography of the coronary arteries and of the bypasses in order to detect their origin and course.
