Abstract 18560: External Calcium Modification Technique to Recanalize a Balloon Uncrossable Chronic Coronary Total Occlusion

Introduction: Despite improvements in equipment and techniques, uncrossable chronic total occlusion (CTO) coronary lesions remain challenging.Case: A 66-year-old male with typical angina and a history of failed CTO PCI was referred to our CTO tertiary center as he did not wish to undergo coronary artery bypass grafting. Transthoracic echocardiography revealed an ejection fraction of 45%, and cardiac MRI demonstrated viability in the LAD region. Coronary angiography revealed a long LAD CTO over 20 mm with heavy calcification (Figure 1a). The J-CTO score was calculated to be 4. The cap of the CTO was semi-ambiguous. The wire was advanced through the highly calcified lesion with the support of a microcatheter but the microcatheter and low-profile balloons were unable to be advanced despite backup with 7 French femoral access and an EBU catheter in place (Figure 1b) Upon failure on using Leopard crawl technique and grenadoplasty and with unfavorable side branch anatomy for STAR technique, cracking the calcification with a balloon advanced over a subintimal hydrophilic wire was considered. A fielder XT-A guidewire was advanced around the CTO lesion in the subintimal area (Figure 1c). A 2x12 mm balloon was inflated at 8 atm over the wire situated in the subintimal area in order the crack the calcification from outside. After extraluminal plaque modification, the wire and the balloon were withdrawn. A microcatheter was then able to be advanced with the support of an anchor balloon over the original true lumen wire (Figure 1d). Then the procedure was successfully completed with balloon dilatation and stent implantation (Figure 1e-f).

Conclusion: External Calcium Modification technique which consists of plaque modification using a balloon in subintimal space (over an intentionally directed wire in subintima and around the calcium) and cracking the calcium from the outer vessel structure can be used as a last resort to overcome balloon uncrossable CTO lesions.