Clinical outcomes in the biomarkers of ketamine (Bio-K) study of open-label IV ketamine for refractory depression

OBJECTIVE

We conducted an open-label clinical trial ("Bio-K") using IV ketamine for treatment-resistant depression to identify biomarkers linked to remission. Here, we report the clinical efficacy and side effect outcomes of Bio-K.

METHODS

Across 4 US sites, 75 patients ages 18-65 with treatment-refractory unipolar or bipolar depression received 3 IV ketamine infusions over an 11-day period. Key exclusion criteria were psychotic symptoms, significant substance abuse, unstable medical conditions, and any use of cannabis. Pre-existing antidepressant medication was maintained. Primary outcome was remission as measured by Montgomery-Asberg Depression Rating Scale (MADRS), with secondary outcome of 50 % reduction in Beck Suicide Scale score. Safety monitoring and varying durations of infusions were also key parameters.

RESULTS

Using remission as MADRS score <10, after 3 infusions 52 % achieved remission, with 67 % achieving response. Of those achieving response after a single infusion, 66 % (22 of 33) reached remission after 3 infusions, while 40 % (16 of 40) non-responders after the first infusion went on to achieve remission after 3 infusions. Only 20 % of non-responders after 2 infusions achieved remission. Most (81 %) participants had significant suicidal ideation at baseline; of these, two-thirds (67 %) experienced at least a 50 % reduction in suicidality. Side effects were minimal. Uniquely, we had three different types of infusion categories, with individuals receiving: (1) slow (100-min) infusions only or (2) regular (40-min) infusions only or (3) a mix of infusion durations. These three infusion groups showed comparable safety and efficacy. Exploration of clinical factors revealed no link between BMI, age, or gender to remission.

CONCLUSIONS

The consistency of outcomes across 4 clinical sites and across multiple instruments, suggests high acute efficacy and safety of IV ketamine for serious depressive episodes. Duration of infusion did not alter outcomes. Meaningfully, 40 % of non-responders after a single infusion did reach remission subsequently, while only 20 % of non-responders after 2 infusions achieved remission, suggesting early response is suggestive for eventual remission. Our data on varying ketamine infusion duration adds novel insights into the clinical administration of this new treatment for refractory and severe patients. Our limitations included a lack of a control group, necessitating caution about conclusions of efficacy, balanced by the utility of reporting "real-world" outcomes across multiple clinical sites. We could also not separately analyze results for bipolar disorder due to small numbers. Together, the Bio-K clinical results are promising and provide significant sample sizes for forthcoming biological markers analyses.

Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

Multi-objective utilization of wood waste recycled from construction and demolition (C&D): Products and characterization

Producing energy and higher value bio-products from waste materials has been proposed as an economically viable opportunity in the renewable energy sector. However, several challenges associated with the integrated biomass conversion processes remain to be resolved. The present study introduces a multi-faceted plant production of thermal energy and biochar from construction and demolition (C&D) wood chips. The overarching objective of the study is to reduce waste materials while simultaneously producing a self-independent clean thermal energy resource along with value-added co-products such as biochar, biogases and/or activated carbon. The combined thermal energy and slow pyrolysis unit relies on 95% of its energy from waste wood chips to produce thermal energy and high value carbon products. The system not only supplies the energy required for the indirect pyrolysis unit but also provides a major portion of thermal energy demanded for the site. A multi-purpose objective of wood waste management, energy production from waste material, high-quality biochar from waste wood (over 80% carbon), and carbon offsets is demonstrated through the utilization of this plant by addressing some of the major previously problems and challenges faced. The information is useful for techno-economic and life cycle analysis in the next study.

Pilot study of an online intervention for young people with a first psychotic episode: Thinkapp

Introduction

Online interventions can be a complement to maintain the long-term effectiveness of psychosocial interventions in First Episode Psychosis (FEP) that have already demonstrated their efficacy in the short and medium term (Calvo et al., 2015).

Objectives

To test the effectiveness of a mobile app–based intervention (Thinkapp) to improve quality of life, functioning and symptomatology, and reduce days of admission and hospitalizations, in young people with FEP.

Methods

Fourteen patients with FEP, aged 14–30, recruited from Gregorio Marañón Hospital, Ramón y Cajal Hospital and AMAFE Foundation in Madrid (Spain) received treatment as usual plus a psychoeducational intervention through a mobile app. Changes in dependent variables over the course of the intervention were assessed by means of a battery of clinical tests at baseline, 3-month and 6-month follow-up using a Wilcoxon test.

Results

Of the fourteen patients included, 7 patients completed the 6-month follow-up and 8 completed the 3-month follow-up. There were significant differences in days of admission (p = 0.042) between baseline and 6-month follow-up. No significant results were observed in other clinical variables.

Conclusions

The study provides preliminary data potentially related to the reduction of days of admissions.

Disclosure

No significant relationships.

Influence of C=O groups on the optical extinction coefficient of graphene exfoliated in liquid phase

Liquid phase exfoliation of graphite is currently one of the most promising graphene production methods at large scale. For this reason, an accurate calculation of the concentration in graphene dispersions is important for standardization and commercialization. Here, graphene dispersions, at high concentrations, were produced by electrochemical exfoliation. Furthermore, a cleaner methodology to obtain graphene oxide by electrochemical exfoliation at high acid concentrations was implemented. The absorption coefficient for graphene and graphene oxide was determined in the optical range (α_660 nm= 1414 (±3%) ml mg^-1 m^-1andα_660 nm= 648 (±7%) ml mg^-1 m^-1, respectively) with an exponential dependence with the wavelength. The difference inαfor both materials is attributed to an increased presence of C=O groups as evidenced by Fourier transform infrared spectroscopy (FTIR), UV-vis and Raman spectroscopy, as well as, in the calculation of the optical extinction coefficient and optical band-gap via Tauc-plots.

Developing an IV Ketamine Clinic for Treatment-Resistant Depression: a Primer

The efficacy of subanesthetic intravenous ketamine for treatment resistant depression (TRD) has spurred a growth of clinics nationwide that provide this service. Ketamine is an FDA-approved drug as an anesthetic but remains unapproved for psychiatric indications, and this status raises a number of short- and long-term safety and efficacy concerns that need to be addressed when implementing and developing this type of clinic. Using a framework of systems, provider, and patient domains, we provide a review of the key challenges in providing ketamine infusions and suggest potential approaches. Under systems issues, we highlight broad stakeholder engagement involving cross-departmental and multidisciplinary considerations, business case development, and delineation of administrative standard operating procedures. In the provider domain, we highlight specific roles for different treatment team members as well as suggested training requirements. In the patient domain, we identify a variety of standard operating procedures involving initial patient assessment parameters, ketamine dosing and administration guidelines, and safety monitoring procedures. Together, this review provides key considerations for developing a ketamine clinic for depression, in an effort to meet the pressing demand for this novel treatment option while helping to ensure its safe implementation.

Implication of heat shock proteins in rotavirus entry into Reh cells

The mechanisms of rotavirus entry into the target cell are described as a multi-step event in which the virions are bound to sialic acid (SA), followed by interaction with heat shock cognate protein 70 (Hsc70), some integrins and protein disulfide isomerase (PDI). However, the cell surface receptor molecules facilitating the entry of tumor cell-adapted rotavirus are not completely characterized. Using infection blocking assays with antibodies to some heat shock proteins (HSPs) and also some inhibitors of these cellular proteins, we were able to identify the cell surface Hsp90, Hsp70, Hsc70, Hsp60, Hsp40, PDI and integrin β3 as receptors of tumor cell-adapted rotavirus in Reh cells. Furthermore, the results also indicated that these rotavirus receptors are associated with lipid microdomains (rafts). Our findings provide evidence that rotavirus tropism for these human acute lymphocytic leukemia cells is explained by the relatively high expression of some HSPs in rafts. The results shown here encourage further research aim at evaluating the potential use of rotaviruses as an oncolytic agent for the treatment of some cancers. Keywords: heat shock proteins; rotavirus; cell receptor; cancer; oncolytic virus.

From ICD10 to ORPHAcodes: paving the way towards improved identification systems for rare diseases

Background

The International Classification of Diseases 10th revision (ICD10) and its clinical modification (ICD10CM) are commonly used for the identification of diseases occurrence worldwide. In Spain, diagnoses are coded with its Spanish version (ICD10ES) since 2016 regardless of the prevalence of diseases. Rare diseases (RDs) are scrambled among common diseases in ICD10 and its derivatives and many RDs dońt have a specific ICD10 code, delaying a proper identification. Orphanet developed a classification system specific for RDs called ORPHAcode. This study aims to characterize whether ICD10ES mapping to ORPHAcodes improves RDs identification and which kind of disorders would benefit the most.

Methods

95% of the disorder level ORPHAcodes indexed at Orphanet was mapped to codes from 20 ICD10ES chapters by comparing the descriptors associated in both classifications. ORPHAcodes were then clustered based on their assigned ICD10ES chapter and the redundancy of each individual ICD10ES code was calculated by counting the ORPHAcodes they mapped to. 3 groups were established: Group 1 (1 ORPHAcode per ICD10ES), Group 2 (between 2-49 ORPHAcodes per ICD10ES) and Group 3 (≥50 ORPHAcodes per ICD10ES).

Results

5588 ORPHAcodes were correlated to 1677 ICD10ES codes. 1051 were group 1, 3261 group 2 (615 ICD10ES) and 1276 group 3 (11 ICD10ES). Most of the Orphacodes correlated to “Q” (&gt;40%), “G” (&gt;14%) and “E” (&gt;12%) chapters of ICD10ES. Regarding specificity, “G” and “Q” were also the only chapters including group 3 ORPHAcodes, while less than 10% of the ORPHAcodes linked to these chapters were in group 1.

Conclusions

New and improved ICD10ES codes are required because just 20% of all ORPHAcodes studied were into group 1. Especial care should be put on the two majoritarian chapters, “Q:Congenital Anomalies” and “G:Nervous System”, that show the lowest specificity for RDs. Complementary use of ORPHAcodes would improve the identification and registry of RDs either.

Funded: Project RD-CODE

Key messages

The lack of a specific chapter for Rare Diseases in the InternationaI Classification of Diseases hinders their identification and therefore their study. Direct mapping between ICD10 and ORPHAcodes or the use of ORPHAcodes for diagnoses codification of Rare Diseases would enable better detection and epidemiological analysis.

Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

Continuation phase intravenous ketamine in adults with treatment-resistant depression

BACKGROUND

Little is known about the antidepressive effects of repeated intravenous ketamine infusions beyond the acute phase of treatment in patients with refractory depression.

METHODS

Twelve subjects with treatment-resistant non-psychotic unipolar or bipolar major depression and suicidal ideation were given repeated (up to 6) thrice-weekly acute-phase intravenous infusions of ketamine (0.5mg/kg, administered over 100min). Those who remitted during acute-phase treatment received continuation-phase treatment that consisted of 4 weekly ketamine infusions, followed by 4 weeks of post-continuation phase follow-up (during which no further ketamine infusions were administered). Clinical measures were assessed at baseline, at 24h following each infusion, at the last acute-phase observation, and during continuation and post-continuation follow-up (acute phase remitters only).

RESULTS

Of the 12 enrollees, 5 (41.7%) remitted and 7 (58.3%) responded to ketamine treatment during the acute-phase. All five subjects who remitted during the acute-phase experienced further depressive symptom improvement during continuation-phase treatment. Four subjects lost remission status during the post-continuation phase, but all were still classified as positive treatment responders at the end of the post-continuation phase. Adverse effects were generally mild and transient during acute- and continuation-phase treatment; however, one subject developed behavioral outbursts and suicide threats during follow-up while hospitalized, and one subject died by suicide several weeks after the end of follow-up.

LIMITATIONS

This was an uncontrolled feasibility study with a small sample size.

CONCLUSIONS

The continuation-phase administration of ketamine at weekly intervals to patients with treatment-resistant depression who remitted during acute-phase ketamine treatment can extend the duration of depressive symptom remission. The antidepressive effect of ketamine persisted for several weeks after the end of continuation-phase treatment. Our results highlight the need for close monitoring of subjects who are at high baseline risk for suicide but do not respond clinically to ketamine. CLINICALTRIALS.

GOV IDENTIFIER

NCT02094898.

Variable Very-High-Energy Gamma-Ray Emission from the Microquasar LS I +61 303

Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.

Epidermolysis bullosa with congenital pyloric atresia: novel mutations in the beta 4 integrin gene (ITGB4) and genotype/phenotype correlations

Epidermolysis bullosa with pyloric atresia (EB-PA: OMIM 226730), also known as Carmi syndrome, is a rare autosomal recessive genodermatosis that manifests with neonatal mucocutaneous fragility associated with congenital pyloric atresia. The disease is frequently lethal within the first year, but nonlethal cases have been reported. Mutations in the genes encoding subunit polypeptides of the alpha 6 beta 4 integrin (ITGA6 and ITGB4) have been demonstrated in EB-PA patients. To extend the repertoire of mutations and to identify genotype-phenotype correlations, we examined seven new EB-PA families, four with lethal and three with nonlethal disease variants. DNA from patients was screened for mutations using heteroduplex analysis followed by nucleotide sequencing of PCR products spanning all beta 4 integrin-coding sequences. Mutation analysis disclosed 12 distinct mutations, 11 of them novel. Four mutations predicted a premature termination codon as a result of nonsense mutations or small out-of-frame insertions or deletions, whereas seven were missense mutations. This brings the total number of distinct ITGB4 mutations to 33. The mutation database indicates that premature termination codons are associated predominantly with the lethal EB-PA variants, whereas missense mutations are more prevalent in nonlethal forms. However, the consequences of the missense mutations are position dependent, and substitutions of highly conserved amino acids may have lethal consequences. In general, indirect immunofluorescence studies of affected skin revealed negative staining for beta 4 integrin in lethal cases and positive, but attenuated, staining in nonlethal cases and correlated with clinical phenotype. The data on specific mutations in EB-PA patients allows prenatal testing and preimplantation genetic diagnosis in families at risk.

[Clinical semiology associated with increased creatinine kinase in patients attending emergency department]

INTRODUCTION

The prognosis of rhabdomyolysis is conditioned by the development of acute renal failure which depends of quick preventive measures. Rhabdomyolysis is diagnosed by measuring plasma creatinkinase and it is usually suspected by the presence of previous putative causal factors like traumatisms. Non traumatic rhabdomyolysis usually lacks of clinical relevant antecedents and the syndrome should be suspected by patient clinical symptomatology; unfortunately, this one has been scarcely studied.

OBJECTIVES

To describe the semiology observed in patients experiencing non traumatic rhabdomyolysis and to identify which symptoms induced to the subject to go to the emergency room in order to facilitate the diagnostic procedure.

PATIENTS AND METHODS

We studied the patients with non traumatic rhabdomyolysis (creatinkinase > 1,000 IU/l) which attended the emergency room in a one year period. We collected data regarding their clinical symptomatology as well as which of them was responsible of his/her coming to the emergency unit. Symptoms were classified in four groups: muscular, urinary, neurological and others.

RESULTS

We evaluated 49 patients. The relative frequency of each kind of symptoms was the following: muscular 51%, urinary 18%, neurological 67%, and others 47%. The absolute frequency of the symptoms which caused the consultation were: muscular 16%, urinary 2%, neurological 48%, others 22%, muscular and neurological associated 6%, and neurological and other associated 6%.

CONCLUSION

CK serum levels should be measured in all of the patients attending the emergency unit who exhibit some type of neurological manifestation.

Oral sweet solution reduces pain-related behaviour in preterm infants

To evaluate the effectiveness of oral sucrose in the prevention of pain-induced crying in preterm infants, a sample of 28 healthy neonates (15M, 13F; gestational age at procedure less than 37 weeks) who were having routine blood drawn by arm venipuncture was studied. Infants were randomly allocated to receive by mouth, using a syringe, 2 ml of one of three solutions: spring water (group W) and sucrose 12 and 24% w/v (groups S12 and S24, respectively), all in water vehicle. After 2 min, while awake, arm venipuncture was performed and duration of crying was measured. The time spent crying was reduced in the group treated with the sweetest solution (S24, n = 8, mean = 19.1 s). No difference was observed between the S12 group (n = 8, mean = 63.1 s) and W group (n = 12, mean = 72.9 s). Physiological measurements were recorded at different time points to evaluate excessive basal and procedural distress.

Effect of acute alcohol intoxication on the opioid system in humans

We investigated the possible relations between the endogenous opioid system and acute alcoholic intoxication in 21 subjects, of whom 13 were drinkers who came to the emergency service with evident symptoms of drunkenness, and 8 were nondrinkers who consumed 1 g alcohol per kg body weight over a short period. Different patterns of changes were found in the two groups for plasma concentrations of beta-endorphin and adrenocorticotropic hormone. In drinkers, plasma levels of both substances increased, whereas in nondrinkers both concentrations decreased, the declines being especially notable 15, 30, and 45 min after ingestion. We found no differences between the two groups in plasma cortisol concentrations. The different levels of these substances may reflect differences in drinking behavior between the two groups.

Plasma concentrations of beta-endorphin, adrenocorticotropic hormone, and cortisol in drinking and abstinent chronic alcoholics

Previous studies of the relationship between the endogenous opioid system and alcohol consumption have reported contradictory results. To shed light on this connection, we compared plasma concentrations of beta-endorphin, adrenocorticotropic hormone, and cortisol in 70 alcoholic persons after different periods of abstinence and a group of 80 control subjects. Plasma beta-endorphin was decreased in alcoholics (18.61 +/- 1.38 vs. 39.31 +/- 3.44 pg/ml), even after more than 10 years' abstinence. This effect may mediated by the tetrahydroisoquinoline system, and may thus result from chronic alcohol consumption. On the other hand, lowered circulating concentrations of beta-endorphin may be a cause, rather than an effect, of alcoholism. Plasma levels of adrenocorticotropic hormone and cortisol did not differ in alcoholics and controls (19.29 +/- 1.66 vs. 13.27 +/- 1.85 pg/ml for ACTH, 20.37 +/- 0.78 vs. 17.22 +/- 0.64 ng/ml for cortisol), and thus appear to have no relation with chronic alcohol consumption.

Classification of alcoholics on the basis of plasma beta-endorphin concentration

Recent findings suggest that a genetic deficit in opioid may be a biological marker of alcoholism. In other words, decreased plasma concentrations of opioids may be a predisposing factor, rather than a consequence, of alcohol consumption. We attempted to classify 88 randomly chosen individuals as alcoholics or nonalcoholics on the basis of plasma concentration of beta-endorphins. This criterion had a sensitivity of 73.30% and a specificity of 79.45%. Its positive predictive value was 42.30%, and its negative predictive value was 93.55%.

Percutaneous balloon valvuloplasty for concurrent mitral, aortic and tricuspid rheumatic stenosis

Percutaneous balloon valvuloplasty has been used with good results to treat rheumatic mitral stenosis. However, its use in degenerative aortic stenosis has shown many limitations. There is little information about balloon valvuloplasty in tricuspid and aortic rheumatic stenosis. This article describes two patients with combined rheumatic mitral, aortic and tricuspid stenosis in which triple percutaneous valvuloplasty was performed in a single procedure.

[The return to work after coronary revascularization]

INTRODUCTION

Work resumption after a therapeutical intervention has been considered as a sensitive indicator of its success. There are some reports analyzing working status after coronary artery revascularization in western countries. However, to our knowledge, similar studies have not been published in Spain.

PATIENTS AND METHODS

We studied 210 patients after coronary artery revascularization surgery or percutaneous transluminal coronary angioplasty. Exclusion criteria were age of 65 or more years and female sex gender (n = 64).

RESULTS

Working patient rate before and after coronary revascularization was respectively 63.2% and 28.9% for surgery, and 57.1% and 41.4% for percutaneous angioplasty (p = 0.11). None of the former inactive patients, with the exception of one in the surgery group, went back to work after the revascularization procedure. Asymptomatic patients after percutaneous angioplasty had a higher postprocedure working rate than symptomatic ones (58.1% vs 11.1%, p < 0.0001). Patients in the surgery group did not show this relation (30% vs 25%, p = 0.69).

CONCLUSIONS

Surprisingly, coronary artery revascularization interventions, mainly coronary surgery, seems to behave in our environment as important determinants of working cessation.

[Atrioventricular block at the nodal level and block of an accessory pathway during percutaneous mitral valvuloplasty]

We describe the simultaneous occurrence of a temporal complete atrioventricular block and a persistent disappearance of preexcitation, in a patient with rheumatic mitral stenosis and a ventricular preexcitation, after an effective percutaneous mitral valvuloplasty. These conduction disturbances were attributed to atrioventricular node and paraseptal atrioventricular pathway trauma, due to transseptal manipulation during the mitral valvuloplasty.

[Percutaneous transluminal angioplasty in aortic coarctation in young adults]

The results of percutaneous balloon angioplasty in 9 cases of adult aortic coarctation are described. One case was associated with bicuspid aortic valve and another with organic aortic stenosis. Two of them were female, and the rest were male. The mean age range between 15-26 years (19 +/- 4.2). Pressure gradients fell from 59 +/- 13 mmHg to 15 +/- 11 mmHg postdilatation (p less than 0.0001), and the internal lumen diameters increase from 5 +/- 3 mm up to 13 +/- 2 mm (p less than 0.0001). In one case an intimal dissection appears as complication. At consequence of these results, the percutaneous balloon angioplasty seems to be a good therapeutic procedure in the adult aortic coarctation.

[Combination of quinidine and verapamil in auricular fibrillation]

The efficacy of the association of verapamil plus quinidine in 70 patients with atrial fibrillation, 64 of them after having cardiac surgery, was assessed. Oral dosage ranged from 825 mg to 1,100 mg for quinidine polygalacturonate and 240 mg to 320 mg for verapamil. All patients but two reached a good control of heart rate (mean heart rate less than 110 beats/min) while arrhythmia persisted. Sixty patients (85.7%) reverted to normal sinus rhythm in a period of 2.4 +/- 1.5 days (mean +/- SD). According to the atrial fibrillation duration three subsets of patients with different conversion rates to sinus rhythm were established (p less than 0.01): group A (lasting from 1 day to 3 months) 31/39 (96%); group B (lasting 3 to 6 months) 18/21 (85.7%) and group C (lasting 6 to 12 months) 5/10 (50%) (p less than 0.01). Plasma quinidine levels were maintained at either near to or therapeutic range (2.6 +/- 0.94 micrograms/ml). Adverse effects comprised one ventricular arrhythmia-induced syncope (quinidine syncope) and two cases of systemic hypotension. Quinidine-verapamil association is a good alternative in the treatment of atrial fibrillation, particularly in those of recent onset, according to the high rates of conversion to normal sinus rhythm, affording control of heart rate while atrial fibrillation persists. Adverse reactions did not differ in severity from those observed with quinidine monotherapy.