The term ‘cardiac electrogram’ (EGM) was initially used to describe the surface ECG, but now EGMs represent the electrical potential within the immediate vicinity of a catheter (including pacemaker and implantable cardioverter defibrillator lead) within the heart. These EGMs are generated from electrodes on catheters that are placed in different regions of the heart: the right atrium, the right ventricle, in the coronary sinus, and near the His bundle. These EGMs, in conjunction with a surface ECG, can then be used to study the timing of electrical activity within the heart, as well as arrhythmias in the cardiac electrophysiology (EP) lab. The goals of this article are to give readers the basics of EGMs, the basics of cardiac EP catheters, and the placement of EP catheters in the heart, and to introduce readers to EGMs and intervals measured.
Recent data suggest that sodium-glucose cotransporter 2 inhibitors have cardioprotective benefits. This effect may extend towards cardioprotection in cancer therapy-related cardiac dysfunction, with proposed mechanisms extending beyond glycemic control to include anti-inflammatory effects, oxidative stress reduction, and metabolic reprogramming. This review synthesizes potential mechanisms, observational data, and emerging trial evidence to support sodium-glucose cotransporter 2 inhibitors as a primary prevention strategy for cancer therapy-related cardiac dysfunction, particularly in anthracycline-exposed populations.
Left ventricular hypertrophy (LVH) is a not uncommon finding on cardiac imaging, seen in 10-20% of adults. LVH can represent a response to a physiological load on the heart (either by athletic training, hypertension, or structural heart issues) or it can represent a primary pathology (e.g. infiltrative disorders, including cardiac amyloidosis and sarcoidosis) or familial/genetic conditions (e.g. hypertrophic cardiomyopathy). LVH is an independent risk factor for adverse cardiovascular events, regardless of its etiology. In this review, we survey the etiologies, clinical approach, and use of multimodality imaging in those with LVH.
Lyme carditis is an uncommon manifestation of disseminated Lyme disease, most frequently presenting as fluctuating atrioventricular block (AVB). We report the case of a middle-aged man with history of frequent deer hunting in a Lyme-endemic region who presented with fatigue and malaise. Skin examination revealed erythema migrans, and the patient had electrocardiographic findings of atrial flutter with high-degree AVB, along with long sinus pauses on telemetry. IV ceftriaxone was started, and subsequent serologic testing confirmed Borrelia burgdorferi infection. Despite appropriate antibiotic therapy, AVB persisted, necessitating permanent pacemaker implantation. This case highlights the importance of early recognition of Lyme carditis, the need for continued cardiac monitoring, and the occasional need for permanent pacemaker implantation in some patients.
Aortic pseudoaneurysms pose a higher risk of rupture due to elevated wall shear stress. Rupture into cardiac chambers is exceedingly rare, with no prior reported cases of an aortic pseudoaneurysm rupturing into the right ventricle. A 57-year-old man with a history of prior surgical ventricular septal defect repair, hypertension, and polysubstance use presented after being found unconscious and reported chest pain. Initial imaging revealed a large ascending aortic pseudoaneurysm (6.6 × 6.1 × 5.5 cm). While under conservative management with antihypertensive therapy, the patient developed cardiogenic shock and was found to have a new aorto-right ventricular fistula on echocardiography. Emergent surgical repair was conducted with patch repair of the fistula, ascending aorta replacement with a 34 mm graft, and placement of a right ventricular assist device for right ventricular failure. Prior cardiac surgery and poorly controlled hypertension likely contributed to pseudoaneurysm formation and subsequent rupture. The development of an aorto-right ventricular fistula introduced significant hemodynamic instability, necessitating high-risk surgical intervention. Multidisciplinary care is crucial for such rare and challenging presentations.
Heart failure (HF) care has increased in complexity over the past decade, with a higher number of interventions and medications offered to patients as part of routine HF care. Studies have consistently shown poor patient understanding of their HF diagnosis and treatment plans, impacting their overall outcomes. Effective communication and literacy-concordant patient education are two key players in comprehensive disease understanding. However, wide variability in HF patient education and the usage of literacy-discordant material have resulted in ineffective patient education, further contributing to fragmented patient understanding of their HF diagnosis. Innovative interventions targeting communication strategies and education delivery methods could significantly alter care delivery and improve multiple domains in HF care.
Mitral annular disjunction (MAD) is an underdiagnosed structural abnormality of the mitral valve apparatus in which the mitral leaflet hinge point is towards the atrium. MAD is associated with mitral valve prolapse and, importantly, increased rates of ventricular arrhythmias, and sudden cardiac death. In this case report and review, we describe the case of a 37-year-old man incidentally found to have MAD during a workup for paroxysmal atrial fibrillation and review the existing literature on the epidemiology, diagnostic methods, natural history, and clinical implications of MAD. Our goal is to highlight important gaps in current guidelines regarding the optimal treatment of patients with MAD.
Transthyretin amyloid cardiomyopathy (ATTR-CM) has transitioned from an underdiagnosed condition to a rapidly evolving therapeutic frontier. This review highlights the expanding treatment landscape, beginning with evidence from key clinical trials for transthyretin tetramer stabilizers and RNA silencers, and extending to novel therapies including gene-editing agents and monoclonal antibody-based fibril depleters. We summarize pivotal trial data - including the ATTR-ACT, HELIOS-B, and APOLLO-B trials - and describe ongoing investigations aimed at broadening therapeutic options. Practical considerations such as route and frequency of administration, tolerability, and regulatory status are outlined to support clinical decision-making. A dedicated section on limitations and special populations addresses the generalizability of trial findings to the diverse patients encountered in practice. Finally, we explore key unresolved questions, including the need for head-to-head comparative trials, the potential role of combination therapy, and the optimal timing for initiating treatment as earlier recognition becomes more common. As novel therapies gain approval this review serves as a timely, focused resource to support clinicians managing ATTR-CM.
Heart failure (HF) is a clinical syndrome characterized by signs and symptoms resulting from any structural or functional deficiency of ventricular filling or blood ejection. The mainstay of initial treatment remains lifestyle modifications, guideline-directed medical therapy, and addressing contributing factors. However, the past two decades have come with significant advances in device therapies to improve morbidity and mortality in HF despite evidence-based management as above. Given the rapidly evolving area of HF research and therapeutic development, it is important for clinicians to be familiar with novel therapies and how they can complement medical management. In this review we discuss the current landscape of novel non-surgical device therapies in HF, their respective trials, major outcomes, and their mechanisms of action and target pathways.
This novel invited article is thanks to CardioNerds: a podcast and platform that democratizes cardiovascular education and invigorates passion for cardiovascular medicine and science. The CardioNerds team held an adult congenital heart disease artistic creations competition in early 2025 for which I (Jamil Aboulhosn) was honored to be selected as winner and asked to publish a piece in this journal, highlighting the role that art plays in my practice of adult congenital cardiology. By sharing select pieces from over the years I will try to take the reader on a short journey through how art helps me understand and teach anatomy, develop interventional and surgical procedures, express emotion, and unwind.
Exercise-induced long QT may mimic congenital long QT syndrome (LQTS), risking misdiagnosis and unnecessary treatment. This scoping review explores its reversibility through detraining and differentiation from congenital LQTS. A systematic search of five databases identified six studies involving 196 subjects. Results showed that exercise-induced long QT is reversible, with QT intervals normalizing after detraining, typically over 1-6 months. Unlike congenital LQTS, affected athletes often lacked genetic mutations or family histories linked to the condition. The difference between congenital LQTS and exercise-induced long QT lies in the reversibility of QT interval prolongation. In those with exercise-induced long QT, the prolonged QT interval would return to normal levels with detraining, unlike in congenital LQTS. Further long-term follow-up is needed to assess the potential arrhythmic risk associated with re-exposure to intensive training. Additionally, negative genetic testing and absence of family history do not entirely exclude congenital LQTS nor indicate benignity, emphasizing the need for careful clinical assessment beyond these factors.
