For regular or standard PCI procedures, the interventional cardiologists access the heart through a catheter (small tube) inserted through a skin puncture. The majority of coronary blockages allows some blood to flow through the vessel. Crossing a wire to deliver equipment through the narrowed artery is, most of the times, not difficult. In contrast, if the patient has a CTO, this means that the vessel has been completely blocked for quite some time. To deliver devices, the interventional cardiologist needs to create a pathway through or around the blockage. As such, opening a CTO requires a combination of specialized devices and techniques, including:
- Double arterial access, in either wrist or groin, for optimized visualization of the occluded vessel.
- Using specialized wires to puncture and cross the complete blockage.
- Navigating the wire around the blockage through the vessel wall and then going back into the vessel.
- Going backwards through tiny bypasses (collateral channels) that arise from non-blocked coronaries. These collaterals are naturally created by the body to bring blood and keep alive the muscle supplied by the blocked vessel.
These techniques can be performed alone or in combination. The ability to perform all of them further increases the likelihood of success. At the London Health Sciences Centre, we have the complete set of expertise and devices to perform all the above-mentioned techniques.