Myocardial Bridging: Review on the Role of Coronary Computed Tomography Angiography.

Myocardial bridging (MB) is a congenital coronary anomaly in which a segment of a coronary artery, most frequently the left anterior descending artery, deviates from its epicardial route by passing through the myocardium. The advent of cardiac computed tomography angiography (CCTA), equipped with its multiplane and three-dimensional functionalities, has notably enhanced the ability to identify MBs. Furthermore, novel post-processing methods have recently emerged to extract functional insights from anatomical evaluations. MB is generally considered a benign entity with very good survival rates; however, there is an increasing volume of evidence that certain MB characteristics may be associated with cardiovascular morbidity. This review is intended to depict the diagnostic and prognostic role of CCTA in the MB context.

The Role of Non-Invasive Multimodality Imaging in Chronic Coronary Syndrome: Anatomical and Functional Pathways.

Coronary artery disease (CAD) is one of the major causes of mortality and morbidity worldwide, with a high socioeconomic impact. Currently, various guidelines and recommendations have been published about chronic coronary syndromes (CCS). According to the recent European Society of Cardiology guidelines on chronic coronary syndrome, a multimodal imaging approach is strongly recommended in the evaluation of patients with suspected CAD. Today, in the current practice, non-invasive imaging methods can assess coronary anatomy through coronary computed tomography angiography (CCTA) and/or inducible myocardial ischemia through functional stress testing (stress echocardiography, cardiac magnetic resonance imaging, single photon emission computed tomography-SPECT, or positron emission tomography-PET). However, recent trials (ISCHEMIA and REVIVED) have cast doubt on the previous conception of the management of patients with CCS, and nowadays it is essential to understand the limitations and strengths of each imaging method and, specifically, when to choose a functional approach focused on the ischemia versus a coronary anatomy-based one. Finally, the concept of a pathophysiology-driven treatment of these patients emerged as an important goal of multimodal imaging, integrating 'anatomical' and 'functional' information. The present review aims to provide an overview of non-invasive imaging modalities for the comprehensive management of CCS patients.

The Non-Invasive Diagnosis of Chronic Coronary Syndrome: A Focus on Stress Computed Tomography Perfusion and Stress Cardiac Magnetic Resonance.

Coronary artery disease is still a major cause of death and morbidity worldwide. In the setting of chronic coronary disease, demonstration of inducible ischemia is mandatory to address treatment. Consequently, scientific and technological efforts were made in response to the request for non-invasive diagnostic tools with better sensitivity and specificity. To date, clinicians have at their disposal a wide range of stress-imaging techniques. Among others, stress cardiac magnetic resonance (S-CMR) and computed tomography perfusion (CTP) techniques both demonstrated their diagnostic efficacy and prognostic value in clinical trials when compared to other non-invasive ischemia-assessing techniques and invasive fractional flow reserve measurement techniques. Standardized protocols for both S-CMR and CTP usually imply the administration of vasodilator agents to induce hyperemia and contrast agents to depict perfusion defects. However, both methods have their own limitations, meaning that optimizing their performance still requires a patient-tailored approach. This review focuses on the characteristics, drawbacks, and future perspectives of these two techniques.

Cardiac magnetic resonance-guided cardiac ablation: a case series of an early experience.

Radiofrequency (RF) catheter ablation has become a widely used therapeutic approach. However, long-term results in terms of arrhythmia recurrence are still suboptimal. Cardiac magnetic resonance (CMR) could offer a valuable tool to overcome this limitation, with the possibility of targeting the arrhythmic substrate and evaluating the location, depth, and possible gaps of RF lesions. Moreover, real-time CMR-guided procedures offer a radiation-free approach with an evaluation of anatomical structures, substrates, RF lesions, and possible complications during a single procedure. The first steps in the field have been made with cavotricuspid isthmus ablation, showing similar procedural duration and success rate to standard fluoroscopy-guided procedures, while allowing visualization of anatomic structures and RF lesions. These promising results open the path for further studies in the context of more complex arrhythmias, like atrial fibrillation and ventricular tachycardias. Of note, setting up an interventional CMR (iCMR) centre requires safety and technical standards, mostly related to the need for CMR-compatible equipment and medical staff's educational training. For the cardiac imagers, it is fundamental to provide correct CMR sequences for catheter tracking and guide RF delivery. At the same time, the electrophysiologist needs a rapid interpretation of CMR images during the procedures. The aim of this paper is first to review the logistic and technical aspects of setting up an iCMR suite. Then, we will describe the experience in iCMR-guided flutter ablations of two European centres, Policlinico Casilino in Rome, Italy, and Haga Teaching Hospital in The Hague, the Netherlands.

Is ventricular sensing always right, when it is left?

BACKGROUND: Ventricular sensing in transvenous cardiac implantable electronic devices (CIEDs) occurs conventionally from the right ventricular (RV) channel, though it evolved from epicardial sensing both in pacemakers and implantable cardioverter-defibrillators (ICDs). HYPOTHESIS: The objective of this study was to observe the reliability of left ventricular (LV) sensing by transvenous leads placed in coronary veins. METHODS: LV leads were used for sensing and arrhythmia detection in clinical situations where placement of an RV lead across the tricuspid valve was either not preferred or not feasible, or RV signal was unsuitable for arrhythmia detection, or in the event of sensing failure of an RV lead under advisory in cardiac resynchronization therapy defibrillator (CRTD) recipients. RESULTS: Thirty-seven patients had an IS-1 LV lead connected to the RV port of CIEDs (17 pacemakers, 5 cardiac resynchronization therapy pacemaker [CRTP], 2 ICDs, and 13 CRTDs). Along a median 41 (25-67) months follow-up, lead performance remained stable; there were neither undersensing nor oversensing of non-cardiac signals. VT/VF were correctly detected and terminated by ATP and shocks (one and three patients, respectively); no inappropriate arrhythmia detection. Device reprogramming occurred in four CRTD recipients because of transient counting the QRS (short intervals) when paced in LV-only, and in two with T-wave oversensing. CONCLUSIONS: Ventricular sensing by an LV lead is feasible in transvenous devices. Sensing programmability is an unmet need: to fix RV lead sensing issues in cardiac resynchronization therapy (CRT) recipients at no risk of infection (no pocket opening); to avoid interaction with the tricuspid valve; to avoid lead redundancy in the vasculature. Moreover, it will be mandatory owing to the loss of lead interchangeability due to the adoption of DF-4 and quadripolar leads.