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Concept: Asymptomatic


Background In the Carotid Revascularization Endarterectomy versus Stenting Trial, we found no significant difference between the stenting group and the endarterectomy group with respect to the primary composite end point of stroke, myocardial infarction, or death during the periprocedural period or any subsequent ipsilateral stroke during 4 years of follow-up. We now extend the results to 10 years. Methods Among patients with carotid-artery stenosis who had been randomly assigned to stenting or endarterectomy, we evaluated outcomes every 6 months for up to 10 years at 117 centers. In addition to assessing the primary composite end point, we assessed the primary end point for the long-term extension study, which was ipsilateral stroke after the periprocedural period. Results Among 2502 patients, there was no significant difference in the rate of the primary composite end point between the stenting group (11.8%; 95% confidence interval [CI], 9.1 to 14.8) and the endarterectomy group (9.9%; 95% CI, 7.9 to 12.2) over 10 years of follow-up (hazard ratio, 1.10; 95% CI, 0.83 to 1.44). With respect to the primary long-term end point, postprocedural ipsilateral stroke over the 10-year follow-up occurred in 6.9% (95% CI, 4.4 to 9.7) of the patients in the stenting group and in 5.6% (95% CI, 3.7 to 7.6) of those in the endarterectomy group; the rates did not differ significantly between the groups (hazard ratio, 0.99; 95% CI, 0.64 to 1.52). No significant between-group differences with respect to either end point were detected when symptomatic patients and asymptomatic patients were analyzed separately. Conclusions Over 10 years of follow-up, we did not find a significant difference between patients who underwent stenting and those who underwent endarterectomy with respect to the risk of periprocedural stroke, myocardial infarction, or death and subsequent ipsilateral stroke. The rate of postprocedural ipsilateral stroke also did not differ between groups. (Funded by the National Institutes of Health and Abbott Vascular Solutions; CREST number, NCT00004732 .).

Concepts: Myocardial infarction, Atherosclerosis, Medical terms, Stroke, Statistical significance, Infarction, Anticoagulant, Asymptomatic


Important data from two large, randomized trials comparing early and late outcomes after carotid endarterectomy and carotid-artery stenting have now been published in the Journal.(1),(2) In common with every other large, multicenter, randomized trial to date, the Asymptomatic Carotid Trial (ACT I) and the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) showed that after the perioperative period, there was no difference in the rate of late ipsilateral stroke after endarterectomy or stenting. In ACT I, which included asymptomatic patients who were deemed to be at average risk, the 5-year rate of ipsilateral stroke (excluding the perioperative period) was . . .

Concepts: Medical terms, Randomized controlled trial, Asymptomatic, Vascular surgery, Carotid endarterectomy


OBJECTIVE: Describe the electrophysiological characteristics in subjects with asymptomatic Wolff-Parkinson-White with sports activities or high professional responsibility. METHODS: Nineteen subjects, mean age 33±13 years (group A). The electrophysiological characteristics were compared with a matched group with symptomatic WPW (group B). RESULTS: At baseline the anterograde refractory period and the anterograde conduction 1:1 over the accessory pathway were longer in group A (300±48ms vs 262±32ms, p<0.05 and 355±108ms vs 307±86ms, p<0.05), respectively. None of group A had a anterograde refractory period<250ms and 58% showed absence of retrograde conduction over the accessory pathway vs 4% of group B (p<0.001). Induction of tachycardia was significantly less in group A (5%) than in group B (92%) (p<0.001). Atrial fibrillation was induced in only one of group A vs 32% of group B (p<0.001). CONCLUSION: We confirm the benign electrophysiological characteristics in asymptomatic compared to symptomatic subjects. Poor anterograde conduction along with absence of retrograde conduction explains the low frequency of tachyarrhythmias and would not support the routine investigation of all asymptomatic subjects. But, due to possible consequences, remains the systematic indication for preventive ablation in the subgroup of asymptomatic subjects with sporting activities or high professional responsibility.

Concepts: Atrial fibrillation, Cardiac electrophysiology, Supraventricular tachycardia, Atrial flutter, Orgasm, Asymptomatic, Tachycardia, Wolff-Parkinson-White syndrome


AIMS: Orthodromic atrioventricular reentrant tachycardia (ORT) is the most common arrhythmia at electrophysiological study (EPS) in patients with pre-excitation. The purpose of the study was to determine the clinical significance and the electrophysiological characteristics of patients with inducible antidromic tachycardia (ADT).METHODS AND RESULTS: Electrophysiological study was performed in 807 patients with a pre-excitation syndrome in control state and after isoproterenol. Antidromic tachycardia was induced in 63 patients (8%). Clinical and electrophysiological data were compared with those of 744 patients without ADT. Patients with and without ADT were similar in term of age (33 ± 18 vs. 34 ± 17), male gender (68 vs. 61%), clinical presentation with spontaneous atrioventricular reentrant tachycardia (AVRT) (35 vs. 42%), atrial fibrillation (AF) (3 vs. 3%), syncope (16 vs. 12%). In patients with induced ADT, asymptomatic patients were less frequent (24 vs. 37%; <0.04), spontaneous ADT and spontaneous malignant form more frequent (8 vs. 0.5%; <0.001) (16 vs. 6%; <0.002). Left lateral accessory pathway (AP) location was more frequent (51 vs. 36%; P < 0.022), septal location less frequent (40 vs. 56%; P < 0.01). And 1/1 conduction through AP was more rapid. Orthodromic AVRT induction was as frequent (55.5 vs. 55%), but AF induction (41 vs. 24%; P < 0.002) and electrophysiological malignant form were more frequent (22 vs. 12%; P < 0.02). The follow-up was similar; four deaths and three spontaneous malignant forms occurred in patients without ADT. When population was divided based on age (<20/≥20 years), the older group was less likely to have criteria for malignant form.CONCLUSION: Antidromic tachycardia induction is rare in pre-excitation syndrome and generally is associated with spontaneous or electrophysiological malignant form, but clinical outcome does not differ.

Concepts: Atrial fibrillation, Supraventricular tachycardia, Atrial flutter, Neurophysiology, Asymptomatic, Tachycardia, Wolff-Parkinson-White syndrome, AV nodal reentrant tachycardia


Baylisascaris procyonis (raccoon roundworm) infection is common in raccoons and can cause devastating pathology in other animals, including humans. Limited information is available on the frequency of asymptomatic human infection. We tested 150 adults from California, USA, for B. procyonis antibodies; 11 were seropositive, suggesting that subclinical infection does occur.

Concepts: Health, Parasites, Nematodes, Rabies, Asymptomatic, Subclinical infection, Santa Barbara, California, Baculum


Clinical guidelines advise against routine electrocardiograms (ECG) in low-risk, asymptomatic patients, but the frequency and impact of such ECGs are unknown.

Concepts: Wavelength, Asymptomatic, Electrocardiography


Fish consumption is recommended as part of a healthy diet. However, there is a paucity of data concerning the relation between fish consumption and carotid atherosclerosis. We investigated the association between habitual fish consumption and asymptomatic carotid atherosclerosis, defined as the presence of plaques and/or increased intima-media thickness (>= 0.90 mm), in non-diabetic participants.

Concepts: Health, Nutrition, Atherosclerosis, The Association, Chronic myelogenous leukemia, Intima-media thickness, Asymptomatic


National guidelines do not agree on the role of carotid screening in asymptomatic patients (ie, patients who have not had a stroke or transient ischemic attack). Recently, several physician organizations participating in the Choosing Wisely campaign have identified carotid imaging in selected asymptomatic populations as being of low value. However, the majority of patients who are evaluated for carotid stenosis and subsequently revascularized are asymptomatic.

Concepts: Medical terms, Angina pectoris, Stroke, Atrial fibrillation, Transient ischemic attack, Sociology, Physician, Asymptomatic


This paper summarises key advances in defining the infectious reservoir for malaria and the measurement of transmission for research and programmatic use since the Malaria Eradication Research Agenda (malERA) publication in 2011. Rapid and effective progress towards elimination requires an improved understanding of the sources of transmission as well as those at risk of infection. Characterising the transmission reservoir in different settings will enable the most appropriate choice, delivery, and evaluation of interventions. Since 2011, progress has been made in a number of areas. The extent of submicroscopic and asymptomatic infections is better understood, as are the biological parameters governing transmission of sexual stage parasites. Limitations of existing transmission measures have been documented, and proof-of-concept has been established for new innovative serological and molecular methods to better characterise transmission. Finally, there now exists a concerted effort towards the use of ensemble datasets across the spectrum of metrics, from passive and active sources, to develop more accurate risk maps of transmission. These can be used to better target interventions and effectively monitor progress toward elimination. The success of interventions depends not only on the level of endemicity but also on how rapidly or recently an area has undergone changes in transmission. Improved understanding of the biology of mosquito-human and human-mosquito transmission is needed particularly in low-endemic settings, where heterogeneity of infection is pronounced and local vector ecology is variable. New and improved measures of transmission need to be operationally feasible for the malaria programmes. Outputs from these research priorities should allow the development of a set of approaches (applicable to both research and control programmes) that address the unique challenges of measuring and monitoring transmission in near-elimination settings and defining the absence of transmission.

Concepts: Immune system, Epidemiology, Infectious disease, Malaria, Infection, Transmission and infection of H5N1, Asymptomatic, Research and development


The prognostic importance of left ventricular (LV) mass in nonsevere asymptomatic aortic stenosis has not been documented in a large prospective study.

Concepts: Medical terms, Prognosis, Left ventricle, Asymptomatic, Aortic valve, Valvular heart disease, Aortic valve stenosis, Aortic insufficiency