Sorajja, Dan

Spontaneous type-1 Brugada patterns are associated with an elevated risk of major arrhythmic events, yet the relationship between varying degrees of pattern burden and the occurrence of a first major arrhythmic event remains unclear. This retrospective cohort study included 64 adult patients with a spontaneous type-1 Brugada pattern, who were identified at Mayo Clinic sites and followed for ≥12 months after the initial diagnosis. All patients underwent at least three 12-lead electrocardiograms (ECGs) within the first year. Individuals with prior major arrhythmic events were excluded. The percentage of ECGs showing a type-1 pattern was calculated and categorized as paroxysmal (<50%), persistent (50–99%), or permanent (100%). During a median follow-up of 92 months, seven patients (11%) experienced their first major arrhythmic event. Of these, one had paroxysmal, four had persistent, and two had permanent spontaneous type-1 Brugada patterns. Although statistical significance was not reached, the hazard ratios suggested a trend toward increased risk with persistent and permanent patterns compared to paroxysmal patterns. No sudden cardiac deaths occurred during follow-up. These findings suggest that a higher burden of spontaneous type-1 Brugada patterns may be associated with increased arrhythmic risk.

Abstract Aims Atrial fibrillation (AF) is the most common cardiac arrhythmia. Although lipoprotein(a) [Lp(a)] is known to be a well-established risk factor for atherosclerotic cardiovascular disease, its role in the development of AF, independent of this association, remains unclear. Methods and results Adult patients from the three Mayo Clinic sites with a baseline Lp(a) and without AF history were included. Patients were categorized into two groups based on their Lp(a) levels: high Lp(a) (≥50 mg/dL) and low Lp(a) (&lt;50 mg/dL). Survival probabilities free from incident AF were compared between Lp(a) groups, during a follow-up period up to 15 years, using the Kaplan–Meier curve and the log-rank test. Multivariable Cox regression analysis was also conducted. A total of 75 376 patients were included (median age: 55 years, 59% males), with a median follow-up duration of 8.8 (inter-quartile range: 3.4, 14.8) years. Incident AF was detected in 5738 (7.6%) patients. Survival probability free from incident AF was significantly lower in patients with elevated Lp(a) (86%) compared with those with low Lp(a) (88%, log-rank P &lt; 0.001). Multivariable analysis adjusted for potential risk factors of AF showed a statistically significant association of elevated Lp(a) with an 11% increase in AF risk (adjusted hazard ratio: 1.11, 95% confidence interval: 1.05–1.18). Conclusion Our study suggests that elevated Lp(a) (≥50 mg/dL) is an independent risk factor for incident AF. Future prospective studies are warranted to validate our results and to test if reducing Lp(a) could mitigate the burden of AF.

Sinus tachycardia (ST) is ubiquitous, but its presence outside of normal physiological triggers in otherwise healthy individuals remains a commonly encountered phenomenon in medical practice. In many cases, ST can be readily explained by a current medical condition that precipitates an increase in the sinus rate, but ST at rest without physiological triggers may also represent a spectrum of normal. In other cases, ST may not have an easily explainable cause but may represent serious underlying pathology and can be associated with intolerable symptoms. The classification of ST, consideration of possible etiologies, as well as the decisions of when and how to intervene can be difficult. ST can be classified as secondary to a specific, usually treatable, medical condition (eg, pulmonary embolism, anemia, infection, or hyperthyroidism) or be related to several incompletely defined conditions (eg, inappropriate ST, postural tachycardia syndrome, mast cell disorder, or post-COVID syndrome). While cardiologists and cardiac electrophysiologists often evaluate patients with symptoms associated with persistent or paroxysmal ST, an optimal approach remains uncertain. Due to the many possible conditions associated with ST, and an overlap in medical specialists who see these patients, the inclusion of experts in different fields is essential for a more comprehensive understanding. This article is unique in that it was composed by international experts in Neurology, Psychology, Autonomic Medicine, Allergy and Immunology, Exercise Physiology, Pulmonology and Critical Care Medicine, Endocrinology, Cardiology, and Cardiac Electrophysiology in the hope that it will facilitate a more complete understanding and thereby result in the better care of patients with ST.

Abstract Background Fever, alcohol, and sodium channel blockers can unmask Brugada pattern and may also induce arrhythmias in Brugada syndrome. We report a case of unmasked Type-1 Brugada pattern presenting with ventricular fibrillation that was induced by a tetrahydrocannabinol vaping. Case summary A 48-year-old male with a past medical history of hypertension treated with hydrochlorothiazide and back pain controlled with tetrahydrocannabinol vaping presented with sudden cardiac arrest from ventricular fibrillation, which was terminated with defibrillation. Electrocardiogram after resuscitation showed a new Type-1 Brugada pattern compared to a previous normal baseline electrocardiogram. Echocardiography and coronary angiogram were unremarkable. Complete blood count and chemistries were unremarkable except for mild hypokalaemia (K = 3.3 mmol/L). After correction of the hypokalaemia, the Type-1 Brugada pattern persisted. Urine drug screen was positive for tetrahydrocannabinol (60 ng/mL). Genetic testing was negative for inherited arrhythmic disease and cardiomyopathy gene panels. Discussion The patient’s type-1 Brugada pattern and ventricular fibrillation were likely induced by vaping tetrahydrocannabinol. He underwent secondary prevention with an implantable cardioverter-defibrillator. He abstains from cannabis and Type-1 Brugada pattern is normalized. There was no arrhythmic event at his 18-month follow-up appointment with abstinence from tetrahydrocannabinol.