Photon Counting Computed Tomography in Heart Failure Patients

Patients with severe acute or chronic heart failure are increasing worldwide. Heart failure clinicians are faced daily with the need to set up short- and long- term therapeutic strategies in line with heart failure etiology and myocardial recovery chances of each patient. Current treatment strategies for severe heart failure also include mechanical circulatory support with artificial devices (such as intraaortic balloon pump, Impella, ECMO, durable left ventricular assist device), which poses specific challenges for cardiac imaging. Through its ability to directly visualize scar and evaluate its transmural extent, cardiac magnetic resonance (CMR) offers a unique advantage over other currently available imaging techniques as a central player in viability assessment in patients with coronary disease, and represents the first line technique to investigate the chances of myocardial function recovery. CMR is also an important tool to provide diagnostic data in patients with non-ischemic heart failure. Unfortunately, CMR is not feasible in many heart failure patients (for example those on MCS therapy) due to the metallic components of the mechanical devices. In these patients, the computed tomography (CT) is the alternative imaging technique to visualize cardiac structures, diagnose complications, and assess possible indications for surgical interventions. However, CT has poorer resolution and do not offer the possibility to evaluate myocardial viability in patients with contraindication to CMR. Therefore, this issue currently represents one of the major unmet needs in the clinical management of severe heart failure patients. Recent technological advances in the field of CT imaging have nevertheless paved the way to explore new pathways of myocardial viability assessment even in patients traditionally deemed unsuitable for CMR. The introduction of photon-counting detectors, in particular, is expected to be the next major breakthrough in clinical x-ray computed tomography