Left ventricular summit -- concept, anatomical description and clinical significance

The left ventricular summit (LVS) is a triangular area located at the most superior portion of the left epicardial ventricular region, surrounded by the two branches of the left coronary artery: the left anterior interventricular artery and the left circumflex artery. The triangle is bounded by the apex, septal and mitral margins and base. This review aims to provide a systematic and comprehensive anatomical description and proper terminology in the LVS region that may facilitate exchanging information among anatomists and electrophysiologists, increasing knowledge of this cardiac region. We postulate that the most dominant septal perforator (not the first septal perforator) should characterize the LVS definition. Abundant epicardial adipose tissue overlying the LVS myocardium may affect arrhythmogenic processes and electrophysiological procedures within the LVS region. The LVS is divided into two clinically significant regions: accessible and inaccessible areas. Rich arterial and venous coronary vasculature and a relatively dense network of cardiac autonomic nerve fibers are present within the LVS boundaries. Although the approach to the LVS may be challenging, it can be executed indirectly using the surrounding structures. Delivery of the proper radiofrequency energy to the arrhythmia source, avoiding coronary artery damage at the same time, may be a challenge. Therefore, coronary angiography or cardiac computed tomography imaging is strongly recommended before any procedure within the LVS region. Further research on LVS morphology and physiology should increase the safety and effectiveness of invasive electrophysiological procedures performed within this region of the human heart. Published in Diagnostics: https://doi.org/10.3390/diagnostics11081423

Left Ventricular Summit—Concept, Anatomical Structure and Clinical Significance

The left ventricular summit (LVS) is a triangular area located at the most superior portion of the left epicardial ventricular region, surrounded by the two branches of the left coronary artery: the left anterior interventricular artery and the left circumflex artery. The triangle is bounded by the apex, septal and mitral margins and base. This review aims to provide a systematic and comprehensive anatomical description and proper terminology in the LVS region that may facilitate exchanging information among anatomists and electrophysiologists, increasing knowledge of this cardiac region. We postulate that the most dominant septal perforator (not the first septal perforator) should characterize the LVS definition. Abundant epicardial adipose tissue overlying the LVS myocardium may affect arrhythmogenic processes and electrophysiological procedures within the LVS region. The LVS is divided into two clinically significant regions: accessible and inaccessible areas. Rich arterial and venous coronary vasculature and a relatively dense network of cardiac autonomic nerve fibers are present within the LVS boundaries. Although the approach to the LVS may be challenging, it can be executed indirectly using the surrounding structures. Delivery of the proper radiofrequency energy to the arrhythmia source, avoiding coronary artery damage at the same time, may be a challenge. Therefore, coronary angiography or cardiac computed tomography imaging is strongly recommended before any procedure within the LVS region. Further research on LVS morphology and physiology should increase the safety and effectiveness of invasive electrophysiological procedures performed within this region of the human heart.

Impact of the COVID-19 pandemic on electrophysiological procedures at a national referral center

Funding Acknowledgements Type of funding sources: None. Background - Introduction: The COVID-19 pandemic has generated serious repercussions on the health system, reducing the number of all cardiology procedures worldwide. Objectives Describe the impact of the COVID-19 pandemic on the procedures performed by the electrophysiology department in a national referral center. Methods We made a retrospective review of our data base and we compared procedures made in the last 3 years since 2017 to 2019 with the procedures made in the 2020. We divide the procedures into two large groups: Cardiac Implantable Electronic Devices (CIED) related procedures (which included implants, revisions, changes, upgrades and extractions) and electrophysiological studies and ablations (which included conventional and complex procedures). Other types of procedures were no included. Results There was a significant reduction in all procedures, the average of procedures performed in the last 3 previous years was 467 (there were 479 in 2017, 411 in 2018 and 511 in 2019), while in 2020 we performed only 319 (p = 0.01); this represents a reduction of 33.4% in the total number of procedures performed in our center. There was no statistical difference regarding the CIED related procedures, the average of procedures of the last 3 previous years was 174 (there were 186 in 2017, 148 in 2018 and 188 in 2019), and in 2020 we performed 189 procedures, this value is near to the average of the last 3 previous years and very close to the value of the 2019 (p = 0.46). Regarding the electrophysiological studies and ablations, the average of procedures of the last 3 previous years was 293 (there were 293 in 2017, 263 in 2018 and 323 in 2019), while in 2020 we performed only 129 procedures, considerably decreasing compared to the previous years (p < 0.01). The reduction in the electrophysiological studies and ablations was 55.97%. The most affected months were April, May and June. Conclusions The COVID-19 pandemic considerably affected the number of electrophysiological procedures in our center, reducing it by 33.4% compared to the previous years. The reduction of procedures fundamentally affected the electrophysiological studies and ablations, reducing them by 55.97%. The number of CIED related procedures were no affected. Electrophysiological procedures Procedures2017201820192017-2019 average2020CIED related procedures186148188174189Electrophysiological studies and ablations293263323293129Total479411511467319Comparative table of the electrophysiological procedures performed in our center in recent years.Abstract Figure. Comparison of the procedures.

Imaging for electrophysiological procedures

Electrophysiology is one of the most rapidly growing area of cardiology. Currently >50,000 catheter ablations are performed in Europe every year and >200,000 patients receive a device for arrhythmia treatment, sudden death prevention, or cardiac resynchronization. The advantages and limitations of fluoroscopy are well known. The rapid development of implantable cardiac devices therapies and ablation procedures all depend on accurate and reliable imaging modalities for preprocedural assessments, intraprocedural guidance, detection of complications, and post-procedural assessment for the longitudinal follow-up of patients. Therefore, over the last decades, imaging become an integral part of electrophysiological procedures.

Multi-Modality Imaging for the Identification of Arrhythmogenic Substrates Prior to Electrophysiology Studies

Noninvasive cardiac imaging is crucial for the characterization of patients who are candidates for cardiac ablations, for both procedure planning and long-term management. Multimodality cardiac imaging can provide not only anatomical parameters but even more importantly functional information that may allow a better risk stratification of cardiac patients. Moreover, fusion of anatomical and functional data derived from noninvasive cardiac imaging with the results of endocavitary mapping may possibly allow a better identification of the ablation substrate and also avoid peri-procedural complications. As a result, imaging-guided electrophysiological procedures are associated with an improved outcome than traditional ablation procedures, with a consistently lower recurrence rate.

Delirium in the intensive cardiovascular care unit

Approximately 10 to 20% of cardiac intensive care unit (CICU) patients are delirious when formally evaluated. However, cardiologists often fail to recognize the signs and symptoms of delirium, frequently missing the diagnosis as a consequence. The CICU has a number of unique predisposing and precipitating factors for delirium, which should be recognized by treating cardiologists. These include; medications (e.g. benzodiazepines, anti-arrhythmics), procedures which are often supplemented by sedatives (e.g. coronary interventions, electrophysiological procedures, structural interventions), mechanical support devices and temporary transvenous pacing (both resulting in immobilization), heart failure, targeted temperature management, and extremes of age related in part to the expanding use of transcutaneous aortic valve replacement (TAVR). In this chapter, we provide a comprehensive update on the etiology, epidemiology, prevention, and treatment of delirium in the CICU patient and provide future directions for the management of this unique and high-risk cohort.

Catheter ablation of focal atrial tachycardia in children using three-dimensional electroanatomic mapping system: a 6-year single-centre experience

Objective: This study demonstrates the clinical and electrophysiological details of catheter ablation conducted in children with focal atrial tachycardia using three-dimensional electroanatomic mapping systems. Patients and methods: Electrophysiological procedures were performed using the EnSite™ system. Results: Between 2014 and 2020, 60 children (median age 12.01 years [16 days–18 years]; median weight 41.5 kg [3–98 kg]) with focal atrial tachycardia and treated with catheter ablation were evaluated retrospectively. Tachycardia-induced cardiomyopathy was developed in 15 patients (25%). Most of the focal atrial tachycardia foci were right-sided (75%), and more than one focus was found in four patients. Radiofrequency ablation was performed in 47 patients (irrigated radiofrequency ablation in seven cases), cryoablation in 9, and radiofrequency ablation and cryoablation in the same session in 4 patients. The median procedural time was 163.5 minutes (82–473 minutes). Fluoroscopy was used in 29 of (48.3%) patients (especially for left-side substrate) with a mean time of 8.6 ± 6.2 minutes. The acute success rate was 95%. The procedure failed in three patients, and recurrence was observed in 3.5% of patients (2/57) during a median follow-up of 17 months (2–69 months). The second ablation was performed in four cases, of which three were successful. Overall success rate was 96.6% with no major complications observed, except in one patient with minimal pericardial effusion. Conclusion: Catheter ablation seems to be an effective and safe treatment in focal atrial tachycardia. Electroanatomic mapping system can facilitate the ablation procedure and minimise radiation exposure.