Is syncope a risk predictor in the general population?

Syncope in the general population is a frequent event often leading to hospitalization, but it is unclear whether syncope in the general population is an independent risk marker for adverse prognosis. In this review, we investigate the current literature and evaluate the prognosis and impact of syncope on adverse outcomes including death and recurrences across different populations with focus on the general population. In wide terms, a syncopal event is related to a higher risk of subsequent falls and injury and cardiac syncope is particularly associated with increased mortality as compared to non-cardiac syncope. The overall prognosis in the general population is by large determined by the underlying presence and severity of a given cardiac disease, but a given underlying cardiac disease can very well be unknown at the time of first syncope so that syncope is the presenting symptom resulting in an independent risk increase. Moreover, syncope is a significant risk predictor of a recurrence across populations. It is im­portant to recognize several risk factors associated with adverse outcome in order to safely navigate in a population where most patients with syncope are healthy and low-risk but where a small number of patients have life-threatening conditions. Further research in the general population should attempt to categorize which patients with syncope need immediate referral and diagnostic testing, and whether this affects the outcome

Impact of Carvedilol and Metoprolol on Inappropriate Implantable Cardioverter-Defibrillator Therapy The MADIT-CRT Trial (Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy)

ObjectivesThe goal of this study was to evaluate the effects of carvedilol and metoprolol on the endpoint of inappropriate implantable cardioverter-defibrillator therapy in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy) study.BackgroundThe impact of carvedilol and metoprolol on inappropriate therapy in heart failure patients with devices has not yet been investigated.MethodsAll patients in the MADIT-CRT study who received a device (N = 1,790) were identified. Using time-dependent Cox regression analysis, we compared patients treated with different types of beta-blockers or no beta-blockers on the primary endpoint of inappropriate therapy, delivered as antitachycardia pacing (ATP) or shock therapy. Secondary endpoints were inappropriate therapy due to atrial fibrillation and atrial tachyarrhythmias, also evaluated as ATP or shock therapy.ResultsInappropriate therapy occurred in 253 (14%) of 1,790 patients during a follow-up period of 3.4 ± 1.1 years. Treatment with carvedilol was associated with a significantly decreased risk of inappropriate therapy compared with metoprolol (hazard ratio [HR]: 0.64 [95% confidence interval (CI): 0.48 to 0.85]; p = 0.002). The reduction in risk was consistent for inappropriate ATP (HR: 0.66 [95% CI: 0.48 to 0.90]; p = 0.009) and inappropriate shock therapy (HR: 0.54 [95% CI: 0.36 to 0.80]; p = 0.002). The risk of inappropriate therapy caused by atrial fibrillation was also reduced in patients receiving carvedilol compared with metoprolol (HR: 0.50 [95% CI: 0.32 to 0.81]; p = 0.004). General use of beta-blockers (93%) and adherence in this study was high.ConclusionsIn heart failure patients undergoing either cardiac resynchronization therapy with a defibrillator or with an implantable cardioverter-defibrillator device, carvedilol was associated with a 36% lower rate of inappropriate ATP and shock therapy compared with metoprolol. Inappropriate therapy due to atrial fibrillation was associated with a 50% lower rate in patients receiving carvedilol compared with those receiving metoprolol. (MADIT-CRT: Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy; NCT00180271

The inflammatory biomarker YKL-40 decreases stepwise after exercise stress test

BACKGROUND: Serum YKL-40 is an inflammatory biomarker associated with disease activity and mortality in diseases characterized by inflammation such as coronary artery disease (CAD). Exercise has a positive effect on CAD, possibly mediated by a decreased inflammatory activity. This study aimed to compare serial measurements of serum YKL-40 before and after exercise in patients with stable CAD versus controls. MATERIALS AND METHODS: Eleven patients with stable CAD verified by coronary angiography (>70% stenosis) and 11 patients with a computer tomography angiography with no stenosis or calcification (calcium score=0) (controls) performed a standard clinical maximal exercise test. Serum YKL-40 was measured before exercise, immediately after exercise, and every hour for 6 h. RESULTS: Cardiovascular risk factors were more prevalent among the CAD patients compared with the controls. CAD patients had higher serum concentration of YKL-40 at baseline compared with controls, median (interquartile range) 94 (52–151) versus 57 (45–79) μg/l. Serum YKL-40 decreased stepwise after exercise, with a median decrease of 16 (13–39) μg/l for the CAD patients and 13 (10–22) μg/l for the controls from baseline to the lowest value. Thereafter, values increased again toward baseline level. Time after exercise was a significant factor for decrease in serum YKL-40 (P<0.0001), but no difference in YKL-40 decrease over time could be demonstrated between the groups (P=0.12). CONCLUSION: Serum YKL-40 is elevated in patients with documented CAD compared with controls, and it decreases stepwise after exercise in both groups, indicating an anti-inflammatory effect of exercise independent of the presence of coronary atherosclerosis

Levels of SARS-CoV-2 antibodies among fully vaccinated individuals with Delta or Omicron variant breakthrough infections

SARS-CoV-2 variants of concern have continuously evolved and may erode vaccine induced immunity. In this observational cohort study, we determine the risk of breakthrough infection in a fully vaccinated cohort. SARS-CoV-2 anti-spike IgG levels were measured before first SARS-CoV-2 vaccination and at day 21–28, 90 and 180, as well as after booster vaccination. Breakthrough infections were captured through the Danish National Microbiology database. incidence rate ratio (IRR) for breakthrough infection at time-updated anti-spike IgG levels was determined using Poisson regression. Among 6076 participants, 127 and 364 breakthrough infections due to Delta and Omicron variants were observed. IRR was 0.29 (95% CI 0.15–0.56) for breakthrough infection with the Delta variant, comparing the highest and lowest quintiles of anti-spike IgG. For Omicron, no significant differences in IRR were observed. These results suggest that quantitative level of anti-spike IgG have limited impact on the risk of breakthrough infection with Omicron

Priorities for Emergency Department Syncope Research

Study objectives There is limited evidence to guide the emergency department (ED) evaluation and management of syncope. The First International Workshop on Syncope Risk Stratification in the Emergency Department identified key research questions and methodological standards essential to advancing the science of ED-based syncope research. Methods We recruited a multinational panel of syncope experts. A preconference survey identified research priorities, which were refined during and after the conference through an iterative review process. Results There were 31 participants from 7 countries who represented 10 clinical and methodological specialties. High-priority research recommendations were organized around a conceptual model of ED decisionmaking for syncope, and they address definition, cohort selection, risk stratification, and management. Conclusion We convened a multispecialty group of syncope experts to identify the most pressing knowledge gaps and defined a high-priority research agenda to improve the care of patients with syncope in the ED