Developments in Coronary Chronic Total Occlusion PCIs
Patients with prior CABG who undergo CTO PCI have lower success rates compared to patients without prior CABG. Among 1363 patients in a multicenter CTO registry, 37% had prior CABG and those patients were older, had more comorbidities, were treated more frequently with the retrograde approach (46.7% vs 27.1%; P<.001), and had lower technical success rates (79.7% vs 88.3%; P=.02), but similar major complication rates (2.1% vs. 1.5%, P=.39) compared to patients without prior CABG. Sakakura et al reported that CTOs in CABG patients are characterized by severe calcification and moderate negative remodeling, helping to explain in part the lower CTO PCI success rates in these patients, which may also be influenced by surgically induced distortion of anatomy. Although PCI of saphenous vein graft (SVG) CTOs has received a class III recommendation in the American College of Cardiology/American Heart Association PCI guidelines because of high restenosis rates, Garg et al reported a 79% technical success rate in 28 SVG CTO lesions, with significant improvement in angina among successful cases and similar incidence of adverse events during long-term follow-up. Hence, although PCI of a native vessel is preferable to SVG PCI, SVG CTO PCI could be considered in highly selected patients where revascularization to the ischemic territory is appropriate and the native CTO is technically difficult to recanalize. In some cases, a diseased SVG can act as a retrograde conduit for performing native coronary artery CTO PCI.
Challenging Subgroups
Patients with prior CABG who undergo CTO PCI have lower success rates compared to patients without prior CABG. Among 1363 patients in a multicenter CTO registry, 37% had prior CABG and those patients were older, had more comorbidities, were treated more frequently with the retrograde approach (46.7% vs 27.1%; P<.001), and had lower technical success rates (79.7% vs 88.3%; P=.02), but similar major complication rates (2.1% vs. 1.5%, P=.39) compared to patients without prior CABG. Sakakura et al reported that CTOs in CABG patients are characterized by severe calcification and moderate negative remodeling, helping to explain in part the lower CTO PCI success rates in these patients, which may also be influenced by surgically induced distortion of anatomy. Although PCI of saphenous vein graft (SVG) CTOs has received a class III recommendation in the American College of Cardiology/American Heart Association PCI guidelines because of high restenosis rates, Garg et al reported a 79% technical success rate in 28 SVG CTO lesions, with significant improvement in angina among successful cases and similar incidence of adverse events during long-term follow-up. Hence, although PCI of a native vessel is preferable to SVG PCI, SVG CTO PCI could be considered in highly selected patients where revascularization to the ischemic territory is appropriate and the native CTO is technically difficult to recanalize. In some cases, a diseased SVG can act as a retrograde conduit for performing native coronary artery CTO PCI.