Learning‐induced modulations of the stimulus‐preceding negativity

The neural basis of feedback expectation, which is crucial in learning theory, has only been minimally studied. Stimulus‐preceding negativity (SPN), an ERP component that appears prior to the presentation of feedback, has been proposed as being related to feedback expectation. The present study showed, for the first time, amplitude modulations of the SPN component during learning acquisition in a trial‐by‐trial associative learning task. The results indicate that SPN could be a plausible electrophysiological index of the cognitive processes engaged while expecting the appearance of relevant feedback during reinforcement learning.     

A counterpoint paper: Comments on the electrocardiographic part of the 2018 Fourth Universal Definition of Myocardial Infarction endorsed by the International Society of Electrocardiology and the International Society for Holter and Noninvasive Electrocardiology

The Fourth Universal Definition of Myocardial Infarction (FUDMI) focuses on the distinction between nonischemic myocardial injury and myocardial infarction (MI), along with the role of cardiovascular magnetic resonance, in order to define the etiology of myocardial injury. As a consequence, there is less emphasis on updating the parts of the definition concerning the electrocardiographic (ECG) changes related to MI. Evidence of myocardial ischemia is a prerequisite for the diagnosis of MI, and the ECG is the main available tool for (a) detecting acute ischemia, (b) triage, and (c) risk stratification upon presentation. This review focuses on multiple aspects of ECG interpretation that we firmly believe should be considered for incorporation in any future update to the Universal Definition of MI.     

Resistance‐associated substitutions in patients with chronic hepatitis C virus genotype 4 infection

Data on the prevalence of resistance‐associated substitutions (RASs) and their implications for treatment with direct‐acting antivirals (DAAs) are sparse in European patients with HCV genotype 4. This study investigated RASs before and after DAA failure in different genotype 4 subtypes and evaluated retreatment efficacies. Samples of 195 genotype 4‐infected patients were collected in the European Resistance Database and investigated for NS3, NS5A and NS5B RASs. Retreatment efficacies in DAA failure patients were analysed retrospectively. After NS5A inhibitor (NS5Ai) failure, subtype 4r was frequent (30%) compared to DAA‐naïve patients (5%) and the number of NS5A RASs was significantly higher in subtype 4r compared to 4a or 4d (median three RASs vs no or one RAS, respectively, P < .0001). RASsL28V, L30R and M31L pre‐existed in subtype 4r and were maintained after NS5Ai failure. Typical subtype 4r RASs were located in subdomain 1a of NS5A, close to membrane interaction and protein‐protein interaction sites that are responsible for multimerization and hence viral replication. Retreatment of 37 DAA failure patients was highly effective with 100% SVR in prior SOF/RBV, PI/SOF and PI/NS5Ai failures. Secondary virologic failures were rare (n = 2; subtype 4d and 4r) and only observed in prior NS5Ai/SOF failures (SVR 90%). In conclusion, subtype 4r harboured considerably more RASs compared to other subtypes. A resistance‐tailored retreatment using first‐ and second‐generation DAAs was highly effective with SVR rates ≥90% across all subtypes and first‐line treatment regimens.     

Reperfusion Therapies for Acute Ischemic Stroke: An Update

Acute ischemic stroke is a major cause of morbidity and mortality in developed countries. Intravenous thrombolysis with tissue plasminogen activator (tPA) within 4.5 hours of symptoms onset significantly improves clinical outcomes in patients with acute ischemic stroke. This narrow window for treatment leads to a small proportion of eligible patients to be treated. Intravenous or intra-arterial trials, combined intravenous/intra-arterial trials, and newer devices to mechanically remove the clot from intracranial arteries have been investigated or are currently being explored to increase patient eligibility and to improve arterial recanalization and clinical outcome. New retrievable stent-based devices offer higher revascularization rates with shorter time to recanalization and are now generally preferred to first generation thrombectomy devices such as Merci Retriever or Penumbra System. These devices have been shown to be effective for opening up occluded vessels in the brain but its efficacy for improving outcomes in patients with acute stroke has not yet been demonstrated in a randomized clinical trial. We summarize the results of the major systemic thrombolytic trials and the latest trials employing different endovascular approaches to ischemic stroke.     

Long-term follow-up of hemodynamic responders to pharmacological therapy after variceal bleeding

Although it is assumed that hemodynamic responders to pharmacological therapy after a variceal hemorrhage are adequately protected from rebleeding, there is no evidence that either this response or its protective effect extend beyond the usual 2-year follow-up featured in available studies. We aimed to assess the maintenance of hemodynamic response and its impact on outcomes in a large cohort of hemodynamic responders during a long follow-up. One hundred three patients with cirrhosis admitted with acute variceal bleeding between 2001 and 2010 were prospectively evaluated. The hepatic venous pressure gradient (HVPG) was determined 5 days after the bleeding and repeated 5-7 days after maximal tolerated doses of nadolol and nitrates. Hemodynamic responders (HVPG ≤ 12 mm Hg or ≥ 20% decrease from baseline) were maintained on drugs and followed up with annual HVPG measurements. Forty-eight patients (47%) were hemodynamic responders. The median follow-up was 48 months (range, 2-108 months). Long-term HVPG evaluations could not be performed in eight patients (four deaths, two rebleedings, two follow-ups <1 year). Among the remaining 40 patients, hemodynamic response was maintained in 26 (65%) and lost in 14 (35%). There were no baseline differences between the two subgroups. However, 100% of alcoholic patients who remained abstinent maintained long-term response, compared with 36% of nonabstinent alcoholics and 50% of patients with viral cirrhosis. Patients with loss of hemodynamic response rebled more during follow-up and showed a higher incidence of death or liver transplantation. Conclusions: After variceal bleeding, long-term maintenance of hemodynamic response to drug therapy is mainly restricted to patients with alcoholic cirrhosis who remain abstinent. The loss of this long-term response carries worse clinical outcomes.