Case 227: Manual of CTO PCI - The invisible septal

A patient was referred for PCI of a RCA CTO due to medically refractory angina. A prior attempt was unsuccessful. Ejection fraction was 40-45%. The RCA CTO had an ambiguous proximal cap, length of approximately 30 mm, diffusely diseased distal vessel, and distal filling via an epicardial collateral from the circumflex and possibly though CC0 septals.
Because of the proximal cap ambiguity, the diffusely diseased distal vessel and the prior failed attempt, a primary retrograde approach was used. An “invisible” septal was successfully crossed using a Suoh 3 wire, but the Turnpike LP could not follow. After inserting a guide extension in the retrograde guide catheter a Caravel microcatheter successfully crossed to the distal RCA. The RCA CTO was successfully crossed from distal to proximal true lumen as confirmed by IVUS. After stenting there was poor antegrade flow, that normalized after placing an additional stent in the distal RCA.