One of the most significant unmet clinical needs in cardiology is the effective treatment of chronic total occlusions (CTOs). For patients with these potentially life-threatening lesions, the option of bypass graft surgery can invite a host of complications, and not every patient is even a candidate. Those patients who are ineligible for surgery face the alternate method of revascularization: a coronary percutaneous coronary intervention (PCI).
Long regarded as extremely challenging and even daunting, CTO PCIs have steadily gained traction in the American cardiology community over the past five years. That’s in part because U.S. physicians have developed faster methods of crossing CTOs that use new, improved catheters and wires to significantly reduce procedural time. That said, a CTO PCI still can take hours to complete, and the delicate task of threading a guide wire through an occlusion to reach the healthier end of the blocked vessel is fraught with obstacles. If you can’t see where to place the wire, you can’t employ the balloons, stents, etc., necessary to open the vessel. Visibility is critical.
Medical imaging’s role
Enter medical imaging. Historically, imaging’s role in facilitating PCI CTOs has consisted of using fluoroscopy, or real-time X-ray, to guide the wire through the occlusion. But unfortunately, fluoroscopy can yield only limited information regarding the wire’s orientation with respect to the occlusion. For this reason, clinicians often repeatedly hit the fluoro peddle and inject contrast in an attempt to better determine the extent of their progress. And every tap of that fluoro peddle exposes the patient – and the clinician – to greater cumulative levels of radiation. What’s more, the repeated doses of contrast can burden patients with renal issues.
Siemens Healthineers recognizes the need for more precise imaging guidance in CTO PCIs, to help the clinician cross that wire without resorting to repeated doses of fluoro and contrast. As we see it, the next step in imaging’s evolution with respect to CTO PCIs is the fusion of multiple forms of imaging to provide more reliable images of occluded vessels. Our new syngo CTO Guidance platform does just that, co-registering a preprocedural computed tomography (CT) image with a fluoroscopy image to provide the optimal camera angle for the PCI procedure. With syngo CTO Guidance, clinicians possess a tool that can deliver a heretofore nonexistent line of site, employing a single camera view and eliminating the need for multiple views via fluoro and contrast injections.
Future guidance
Armed with this fused-imaging roadmap of the occluded vessel, clinicians who may have felt that they worked with significantly compromised images during past CTO PCIs can potentially enjoy heights of unobstructed vision akin to radar guidance. And the ability to see more clearly may help them complete CTO PCIs more quickly, without resorting to a multiple-dose, contrast-heavy approach. And the sooner the PCI is completed, the sooner the patient can leave the hospital. In this manner, improved imaging can help enable better outcomes for CTO PCI patients.
As medical imaging continues to demonstrate increased value in the treatment of CTOs -- through syngo CTO Guidance as well as other, as-yet-unveiled innovations -- expect attention to focus not just on improving visualization, but also on achieving those enhanced views with dramatically less patient dose. Dose levels that have already fallen dramatically over the past 15-20 years could be reduced by near-future technologies to near-infinitesimal levels.
That goal – to provide better tools to improve the outcome of CTO treatment – can only be realized when medical imaging companies like Siemens Healthineers collaborate with manufacturers of stents, catheters, and other medical devices that are crucial to the successful completion of CTO PCIs. Siemens Healthineers is proud to participate in these sorts of industry collaborations, to provide the cardiology community with tools that can help them cross that CTO – and cross that finish line to a more successful patient outcome.
