The Role of the Autonomic Nervous System in Vasovagal Syncope.

The mechanism of vasovagal syncope (VVS) is multifaceted and involves a delicate balance within the autonomic nervous system (ANS). This review delves into the complex interplay between the ANS and VVS, elucidating the pivotal role that autonomic imbalance plays in the pathophysiology of this condition. Through a comprehensive exploration of the sympathetic and parasympathetic branches of the ANS, this review provides insights into the mechanisms that underlie VVS.

Complications related to pacemakers and other cardiac implantable electronic devices: essentials for internists and emergency physicians.

With the aging population, improving technology, and expanding indications for diagnosing and treating arrhythmias and heart failure, many patients are receiving cardiac implantable electronic devices (CIEDs) such as pacemakers and implantable cardioverter defibrillators. Consequently, patients with CIEDs are frequently encountered in the emergency department and in the wards. It is imperative that emergency physicians and internists have a strong foundation on CIEDs and their potential complications.

Validation of the Emory Risk Score in the Transcatheter Aortic Valve Implantation Population: A Canadian Perspective.

Background: Permanent pacemaker (PPM) implantation may be indicated post-transcatheter aortic valve implantation (TAVI). The Emory Risk Score (ERS) is a validated predictive risk score of the need for a PPM post-TAVI using a balloon-expandable valve. Our objectives were to determine the validity of the ERS in our local TAVI population with both balloon-expandable and self-expanding valves and to identify additional electrocardiographic (ECG) parameters predictive of the need for a PPM post-TAVI.

Prevalence and Functional Implication of Silent Coronary Artery Disease in Marathon Runners Over 40 Years of Age: The MATCH-40 Study.

Background: Marathon participation is becoming increasingly popular among individuals ≥40 years of age. Little is known about the prevalence of subclinical coronary artery disease (CAD) and corresponding ischemia in this patient population. The study objectives are: (1) to characterize the prevalence of silent CAD in marathoners ≥ 40 years old using cardiac computed tomography angiography (CCT); and (2) if subclinical CAD was detected, to determine the functional significance of occult lesions by stress echocardiography (SE).

Predictors of appropriate shock after generator replacement in patients with an implantable cardioverter defibrillator.

Background: Implantable cardioverter defibrillators (ICDs) are indicated for the primary prevention of sudden cardiac death in patients with reduced left ventricular ejection fraction (LVEF). The ongoing risk/benefit profile of an ICD at generator replacement is unknown. This study aimed to identify predictors of appropriate ICD shocks and therapies after first ICD generator replacement, and its procedure-related complications.

"I Tripped and Broke My Heart": A Case Report of Right Atrial Rupture.

A 66-year-old woman tripped and fell onto outstretched hands. She did not hit her chest. She developed chest pain and presented to the emergency department in shock.

Autoimmune heparin-induced thrombocytopenia and venous limb gangrene after aortic dissection repair: in vitro and in vivo effects of intravenous immunoglobulin.

Background: Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder characterized by heparin-dependent antibodies that activate platelets (PLTs) via PLT FcγIIa receptors. "Autoimmune" HIT (aHIT) indicates a HIT subset where thrombocytopenia progresses or persists despite stopping heparin; aHIT sera activate PLTs strongly even in the absence of heparin (heparin-independent PLT-activating properties). Affected patients are at risk of severe complications, including dual macro- and microvascular thrombosis leading to venous limb gangrene.

Right ventricular pacing is associated with increased rates of appropriate implantable cardioverter defibrillator shocks.

Background: Right ventricular (RV) pacing has been associated with increased risk of pacemaker-induced cardiomyopathy, hospitalization and death among patients with implantable cardioverter defibrillators (ICDs). Little is known about its association with ventricular tachyarrhythmias. We hypothesize that RV pacing is associated with increased incidence of appropriate ICD shocks and death.

Atrial fibrillation in elderly patients with implantable loop recorders for unexplained syncope.

Background: An implantable loop recorder (ILR) assists in the diagnosis of unexplained syncope and atrial fibrillation (AF). Both become prevalent with age. Limited data exist describing the incidence of AF as the diagnostic rhythm underlying syncope in the elderly.

Multimodality Imaging of a Giant Right Coronary Artery Aneurysm.

We describe a case of a 54-year-old woman who had a right cardiac mass found on coronary angiography. Echocardiography, computed tomography, and cardiac magnetic resonance imaging characterized it as a thrombosed giant right coronary artery aneurysm. This was confirmed on pathology.