48 year-old male with known multivessel CAD since 2012 and prior PCI’s of LAD, Ramus and Circumflex presented with CCS Class III angina and moderate inferior wall ischemia on stress MPI. A Cardiac Cath on September 2, 2015 revealed one vessel CAD: CTO of distal RCA filling via retrograde LAD-septal collaterals and antegrade bridge collaterals, and patent interventional sites of left system with normal LV function and SYNTAX Score of 12.0. Patient is now planned for PCI of distal RCA CTO by retrograde recanalization approach using LAD-septal collaterals.
Q&A
Q
Your institution performs a very large number of CTO, both antegrade and retrograde. How often do you obtain CT angiogram?
A.
We have not followed CT angio prior to CTO PCIs but roughly 10% of pts are getting CTA before the CTO PCIs. Also we have not been studying those CTA as relates to the CTO procedure, and prediction of successful outcome. We will soon start incorporating CTA analysis in our CTO recanalization algorithm.
Q
Will you be using more CT angiography pre-CTO ?
A.
Yes and is well supported by few publications in this field.
Q
Is CT angiography predictive or navigational for CTO?
A.
I believe that to be predictive and especially not to attempt the cases which have low likelihood (<50%) of success.
Q
Would CT angiography be more helpful for evaluating for a retrograde or simply to separate subtotal from total occlusions?
A.
CT angio will be more helpful for retrograde recanalization approach but also for procedural success of CTO by either approach. Yes it will definitely identify the subtotal occlusion which will have very high procedural success (>95%).
Q
In your experience, which factor is the most negative predictor for CTO success by CT angiography?
A.
It will be the length and degree of calcification of the CTO lesion which will be the strongest predictor of CTO success; shorter lesion <20mm and less then severe calcification will predict >90% procedural success.
Q
Same factor for both antegrade and retrograde approach?
A.
For retrograde recanalization additionally the course and tortuosity of the retrograde collaterals, will predict the CTO success; angulated septal collaterals >45degree will have low procedural success.
Q
In today's remarkable CTO case, what would you have done had the ASTATO wire not worked?
A.
Dr Kini tried all other CTO wires including Confianza 9-12 and Progress 200T, but could not succeed and only ASTATO wire which has tip strength of 20gm pierced the distal cap of dRCA retrogradely. Hence it is very likely that without ASTATO wire we would have been unsuccessful today retrogradely. In that case we would have also tried antegradely to improve the success of CTO.
Q
Please tell us three most important factors for selecting septals?
A.
Size, course and communication of the septal collaterals are the three most important factors in selecting the septal for retrograde recanalization.
Q
Three most important techniques for handling the Corsair?
A.
Corsair needs to be rotated 12-16 turns in clockwise direction and then counter clock 8-10 turns before advancing forward. Also put the torquer on the guidewire near the Corsair back hub to have full control of the device.
Q
What are your most preferred externalizing wires?
A.
Still Viperwire 0.014 (335cm) of CSI is by far the best externalization wire followed by RG3 of Abbott (330cm).
