A cool modality to restore sinus rhythm

Background

Slowing electrical conduction by cooling the myocardium can be used for defibrillation. We previously demonstrated the efficacy of a small cold device placed in oblique sinus (OS) in terminating atrial fibrillation (AF). However, the parameters needed to achieve effective atrial defibrillation are unknown.

Purpose

Assess effect of the size of cooled myocardium on frequency of AF termination in acute canine animal models.

Methods

Sternotomy was performed under general anesthesia in 10 acute canine experiments. AF was induced using rapid atrial pacing and intra-myocardial epinephrine and acetylcholine injections. Once AF sustained for at least 30s, either a cool (7–9°C) or placebo (body temperature) device was placed in the OS. Four device sizes were tested; ½X½, ¾X¾, and 1X1 inch devices and two ¾X¾ inch devices placed side by side simultaneously. Time to AF termination was recorded. Chi-squared or Fisher's exact test were used to compare the frequency of arrhythmia termination with cooling versus placebo.

Results

A total of 166 applications were performed (89 cool vs 77 placebo) in 10 animal experiments. Overall, AF terminated in 82% of the cooling applications vs. 67.5% of placebo (P=0.03, Figure 1). For the ½X½ inch device 88% of cold applications restored sinus rhythm vs. 63.6% for placebo (P=0.05). The frequency of sinus restoration for cold ¾X¾, 1X1 and two ¾X¾ side by side devices was 86.7%, 83.3% and 70% respectively. Time to sinus restoration when achieved was within three minutes was also not significantly changed.

Conclusion

Placing a cool device in the oblique sinus can terminate AF and efficacy is not affected by the size of device.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): MediCool Technologies

The role of beta-carbolines (harman/norharman) in heroin addicts

Endogenous substances resulting from interactions between alcohol and possibly opioid metabolites and neurotransmitters (dopamine, indolamines) could be mediators of the pathochemical process towards dependence. Beta-carbolines (harman/norharman) are increased in alcoholics and — according to the presented results — in heroin addicts. Psychopathological disorders such as anxiety or depression do not seem to influence the level of beta-carbolines.

Frontocortical N-acetylaspartate reduction associated with long-term i.v. heroin use

To examine possible metabolic frontal lobe alterations in i.v. heroin-dependent patients with different histories of concomitant substance use, N-acetylaspartate (NAA), a putative marker of neuronal viability, was measured by (1)H-MRS. Compared with controls, NAA levels in patients were reduced by 7% in gray matter (p = 0.015) but not in white matter. To what extent comorbid conditions or substance use, including alcohol, contributed to these frontocortical metabolic changes remains to be elucidated.

Onset and pattern of substance use in intravenous drug users of an opiate maintenance program

OBJECTIVES

To assess the initiation of substance use of participants in an opiate maintenance program by a cross-sectional survey.

METHOD

Participants (n=184) filled out a questionnaire assessing age at initial substance use and age at onset of regular drug use.

RESULTS

Of 15 substances investigated, alcohol, nicotine, analgesics and marijuana were initiated and consumed regularly before the age of 18 years. Barbiturates, benzodiazepines, cocaine, and opiates were begun later. The time gap between initial and regular use varied depending on the substance. Regular use exceeded 50% for alcohol, benzodiazepines, cocaine, heroin, marijuana and nicotine.

CONCLUSIONS

Specific knowledge about the age of onset and sequence of substances used by drug addicts may help to prevent substance use more age specifically.

Double-blind randomized trial of buprenorphine and methadone in opiate dependence

This study compared the safety and efficacy of sublingual buprenorphine tablets with oral methadone in a population of opioid-dependent individuals in a double-blind, randomized, 6-week trial using a flexible dosing procedure. Fifty-eight patients seeking treatment for opioid dependence were recruited in three outpatient facilities and randomly assigned to substitution with buprenorphine or methadone. The retention rate was significantly better in the methadone maintained group (90 vs. 56%; P<0.001). Subjects completing the study in both the treatment groups had similar proportions of opioid positive urine samples (buprenorphine 62%; methadone 59%) and positive urine specimens, as well as mean heroin craving scores decreased significantly over time (P=0.035 and P<0.001). The proportion of cocaine-positive toxicology results did not differ between groups. At week six mean stabilization doses were 10.5 mg per day for the sublingual buprenorphine tablet, and 69.8 mg per day for methadone, respectively. Patient performance during maintenance was similar in both the groups. The high attrition rate in the buprenorphine group during the induction phase might reflect inadequate induction doses. Thus, buprenorphine is a viable alternative for methadone in short-term maintenance treatment for heroin dependence if treatment induction is done with adequate dosages.

Do caffeine-containing analgesics promote dependence? A review and evaluation

OBJECTIVE

Debates about the suspected association between kidney disease and use of analgesics have led to concern about whether caffeine could stimulate an undesirable overuse of phenacetin-free combined analgesics. A committee was asked to critically review the pertinent literature and to suggest guides for clinical practice and for consideration of international regulatory authorities.

PARTICIPANTS

A group of international scientists, jointly selected by the regulatory authorities of Germany, Switzerland, and Austria and the pharmaceutical industry.

EVIDENCE

All invited experts evaluated relevant literature and reports and added further information and comments.

CONCLUSIONS

Caffeine has a synergistic effectiveness with analgesics. Although caffeine has a dependence potential, the potential is low. Experimental data regarding dependence potential for caffeine alone may not correspond to the conditions in patients with pain. Withdrawal is not likely to cause stimulation or sustainment of analgesic intake. For drug-induced headache, no single or combined analgesic was consistently identified as causative, and no evidence exists for a special role of caffeine. Strong dependence behavior was observed only in patients using phenacetin-containing preparations, coformulated with antipyretics/analgesics and caffeine. This finding may have led to the impression that caffeine stimulates overuse of analgesics.

SUMMARY

Although more experimental and long-term data would be desirable to show possible mechanisms of dependence and to offer unequivocal proof of safety, the committee concluded that the available evidence does not support the claim that analgesics coformulated with caffeine, in the absence of phenacetin, stimulate or sustain overuse.

A comparison of heroin chasers with heroin injectors in Switzerland

In a cross-sectional multicentre study, we compared the characteristics of heroin chasers and heroin injectors. Subjects were 162 primarily opioid-dependent volunteers for whom either chasing (n = 85) or injecting (n = 77) was the principal route of heroin administration. Each subject was rated by means of the Swiss version of the European Addiction Severity Index. Additionally, subjects completed a questionnaire battery including the Severity of Dependence Scale, the Symptom Checklist SCL-90-R, a self-constructed peergroup questionnaire and a semantic differential list to assess the connotative meaning of heroin chasers and injectors. The heroin injectors were older and more likely to use one or more other drugs besides heroin than the chasers. They had longer heroin-using careers, a longer duration of detention and a higher prevalence of some type of hepatitis. In conclusion, the differences between chasers and injectors were rather related to a longer history of heroin use than to the route of heroin administration.

Rapid cortical hemoglobin deoxygenation after heroin and methadone injection in humans: a preliminary report

The short-term effects of intravenous opioids (heroin 20-300 mg, methadone 30-180 mg) on cortical hemoglobin oxygenation were examined by near infrared spectroscopy in ten opioid-dependent subjects and were compared with the effects of saline in ten age-matched normal controls. Heroin and methadone produced a rapid and dramatic decrease in cortical hemoglobin oxygenation. Saline had no effects. Opioid-induced acute deoxygenation of cortical hemoglobin is most likely associated with respiratory depression. Thorough medical monitoring is strongly recommended in intravenous opioid maintenance treatments.

Comparison of buprenorphine and methadone in the treatment of opioid dependence. Swiss multicentre study

A three-centre, randomised, double-blind study was designed to compare the efficacy and safety of buprenorphine and methadone. This was the first European study to compare these agents and was based on a previous trial performed in the US. Opioid-dependent subjects were randomised to receive either sublingual buprenorphine or oral methadone daily. Both objective and subjective measures of efficacy were monitored weekly, and safety parameters were regularly monitored over the entire six-week study. Urinalysis showed that the two treatments were similar with a slight increase in opioid-negative urines noted in both groups. The retention rate in the buprenorphine group was lower than in the methadone group, although it has been suggested that the buprenorphine dose may have been too low for some patients. None of the side effects noted were considered serious and all were attributable to chronic opioid dependence. Experience of two years substitution treatment in Fribourg suggests that initial induction onto buprenorphine allows for patients to be subgrouped before being given the most appropriate maintenance agent. Further investigation is required into the different dose-related effects of buprenorphine seen in particular subsets of addicts.

[Drug dependence--diagnostic and therapeutic aspects]

In Switzerland, dependence on these drugs reflects primarily the relationship between patient and doctor, due to the strict regulations. Drugs involved are in most cases benzodiazepines and other sedatives, less frequently stimulants including weight-control products and drugs containing opioids. Patients' characteristics and motivations include 1.) attempt for specific psychotropic effects, 2.) habituation developed during long-term treatment, 3.) overconsumption of drugs without seeking specific psychotropic effects. Clinical syndromes and therapeutic and preventive strategies are described.

High prevalence and coinfection rate of hepatitis G and C infections in intravenous drug addicts

BACKGROUND/AIMS

The hepatitis G virus is a newly discovered RNA virus which is possibly transmitted parenterally. Hepatitis G virus is associated with acute or chronic hepatitis and may lead to cirrhosis and liver cancer, characteristics shared by the hepatitis C virus. Hepatitis C virus is prevalent in drug users, but the frequency and role of hepatitis G virus is not yet well established.

METHODS

One hundred and seventeen heavy i.v. drug users were enrolled in a prospective, controlled, randomized study for i.v. administration of heroin and/or methadone. Hepatitis G virus was detected using a hot start polymerase chain reaction followed by an ELISA polymerase chain reaction assay. Hepatitis C virus genotyping was done using the Inno-Lipa strip assay.

RESULTS

Hepatitis G virus infection was detected in 35% (41/117) of the study population and hepatitis C virus infection in 95.7% (112/117). Ninety-seven percent of hepatitis G virus positive patients were coinfected with hepatitis C virus, of whom 75% were infected with hepatitis C virus genotype 3a. This genotype was prevalent in 48.3% of patients infected with hepatitis C virus alone. The presence or absence of hepatitis G virus infection had no influence on chronic hepatitis. Twenty-two percent of patients who started injecting heroin before 1980 and 40% of those who started after 1980 were hepatitis G virus positive. Overall, 16 patients were infected with human immunodeficiency virus, six were coinfected with hepatitis G virus and hepatitis C virus, and 10 only with hepatitis C virus.

CONCLUSIONS

Hepatitis G virus infection is highly prevalent in i.v. drug users, but less frequent than hepatitis C virus infection. The fact that all but two patients were coinfected with hepatitis C virus, 75% with one genotype, supports a common route of transmission for both viruses. The course of hepatitis C virus infection is not altered by hepatitis G virus infection.

[Initial results with withdrawal treatments of male and female participants in the diversified Janus opiate prescription project in Basel]

Since the beginning of the 'Janus' opiate project in Basel in which severely opiate-dependent persons are treated intravenously with heroin, morphine or methadone 11 from 160 participants (to november 1995) were treated in the withdrawal and intervention unit at the psychiatry clinic of the university of Basel. 7 patients sought a total, 4 a partial withdrawal. Whereas the 4 patients wanting withdrawal from consumption of drugs in addition to study drugs all reached their goal 4 of the 7 persons aiming at total withdrawal interrupted treatment prematurely. The 3 patients who were successful are-as far as the authors know-still off opiates. Substitution of intravenous opiates provided by 'Janus' with oral methadone and slow tapering off of the latter over days to weeks occurred mostly without problems. Participants of the 'Janus' project thus desired a withdrawal oriented treatment with equal frequency and had not less success than persons substituted with oral methadone in achieving this goal.

[Sleep disorders in chronic pain and generalized tendomyopathy]

Patients with a chronic pain syndrome often suffer from sleep disturbance. As both symptoms are frequent in the fibromyalgia syndrome, these patients in particular have been examined in this regard. No clear polysomnographic evaluation of the subjectively experienced sleep disturbance in these patients has been done so far. Therefore, we recorded the sleep EEG of 13 patients with a fibromyalgia syndrome in order to objectively characterize their sleep. Furthermore, we were interested in the relationship between the sleep alterations and pain intensity. In a subsequent placebo-controlled study based on pathophysiological considerations, we attempted to beneficially influence the sleep disturbance and the pain syndrome with the 5-HT2-receptor antagonist ketanserine, as this system has been proved to play a major role in the regulation of both sleep and pain. The results of our studies in patients with fibromyalgia show that the alteration of sleep is mainly characterized by a disturbance of sleep continuity associated with the experience of pain intensity. The application of 5-HT-receptor-antagonists may be a new strategy for the common treatment of sleep disturbance and the pain syndrome which needs to be evaluated in further studies. Duration of the patients' illness seems to be a predictive value in relation to intensity of the symptoms and the therapeutic outcome.

[Sleep and addiction]

Sleep disorders and depressive symptoms are concomitant features in patients with addictive disorders. In this study, patients with addiction (alcohol and opioid, resp.) and with major depression (DSM-III-R) were examined with a sleep EEG and compared to age-matched controls. An age-dependent decrease of total sleep time and slow-wave sleep (SWS) was demonstrated. Sober patients with alcohol dependency showed a decrease of SWS, whereas patients with opioid dependency substituted with methadone showed a disorder of REM sleep (REM suppression). Depressive patients revealed a disturbance of sleep continuity and REM sleep (increased REM sleep). The neurobiological differentiation by sleep EEG is of interest for research and clinical practice.

[Substitution as a possibility for the treatment of opiate dependent patients]

The treatment of patients who are dependent on opiates has definitely been including drug substitution besides withdrawal and weaning in the Swiss urban community ("Kanton") of Basel City since 1980. After a significant increase of treatments in 1987 in connection with the spread of HIV infections, more than 800 patients were presently receiving substitution treatment according to a descentralised schedule. The type of long-term treatment is illustrated by sociodemographic and treatment data of 500 substituted individuals who are mostly being looked after always by the same persons entrusted with caring for them. This represents a flexible, economically feasible and highly individual type of care and treatment that can help to reduce illegal drug consumption and hence the undesirable events associated with it in an urban district such as Basel city.

[Withdrawal treatment of drug dependent patients with the aim of achieving abstinence]

The treatment of patients who are dependent on drugs is undergoing a conceptual change, and in this connection more attention is being paid to a qualified withdrawal and weaning. More than 200 withdrawals are being performed annually in the U2 section of the Department of Psychiatry of the University of Basel. The authors report on the composition of the patient groups, their withdrawal symptoms and the therapy offered. In respect of the continually too frequent discontinuations of therapy attention is drawn to the need for a really efficient pharmacotherapy.

[Evaluation of a drug withdrawal unit]

New concepts of addiction treatment pay greater attention to the organization of qualitative withdrawal. On the ward U2 of the PUK, over 200 drug withdrawals are carried out each year. We report the demographic characteristics of our patient sample, quantify their withdrawal symptoms and describe the range of therapeutic techniques applied. We emphasize the necessity for an efficacious pharmacotherapy to minimize the drop-out rate.

[Acamprosate--a stabilizing factor in long-term withdrawal of alcoholic patients]

In a one-year double-blind-treatment study with acamprosat (six months with and six months without substance) the efficiency of this new medicament could be proved. The number of relapses in the treatment group was significantly lower during the first 30 days with a trend to further 150 days. The substance caused very few side effects.

[Drugs and violence]

The physician is confronted with victims of drug-related violence in emergency situations, especially in excitations (cocaine) or alcohol-induced intoxications. Moreover, the topic of drug-related violence should not only engage criminologists, specialists in legal and forensic medicine, but also every doctor because of the implications concerning interactions of drugs and society in which the medical profession ist deeply involved.

[Beta-carbolines (harman/norharman) are increased in heroin dependent patients]

Endogenous substances resulting from interactions between alcohol and possibly opioid metabolites and neurotransmitters (dopamine, indolamines) are mediators of the pathochemical process towards dependence. Beta-carbolines are increased in alcoholics and--according to our own results--in heroin-addicts. Still unclear is the impact of other psychopathological disturbances like states of anxiety or depression; unclear is also, if it has to be interpreted as state, trait or residual marker of the dependence syndrome.

[Future prospects in treatment of drug dependent patients]

During the last 25 years, an important evolution in therapeutic-rehabilitative strategies for drug addicts was observed. Many inputs came from social pedagogics. Great demands are again put on the medical profession in relation to AIDS and substitution programs. In the future the engagement of the medical profession will be required more again, particularly the psychosocial competence of doctors as well as the medical-biological research.

[Substitute drug treatments with methadone]

Methadone maintenance treatment for patients with opiate addiction, started in the Canton of Basel in 1980, today includes more than 600 patients, with a marked increase since 1987 due to a change in inclusion criteria following the spreading of HIV infections. Data from 500 patients, gathered in 1991/92 on sociodemographic and treatment characteristics, emphasize the long-term aspect of the methadone maintenance treatment and the necessity of an intensive psychosocial treatment.

[The importance of work and unemployment for the long-term outcome and rehabilitation of drug dependent patients]

Physicians generally have to deal with therapy and less with rehabilitation of diseases. Employment and the necessary capacity and skills are to be focused on therapeutically in every second drug addict or alcoholic. The continuation of work is an important aim of secondary and tertiary prevention. Some general psychosocial aspects concerning this topic are discussed.

[The Basel dependence study]

In a survey of 177 patients of several outpatient departments and private practices in the area of Basel there were 23% with a dependence syndrome according to the diagnostic guidelines of ICD-10. Sedatives and hypnotics were the mostly mentioned psychotropic substances in this group. In a second survey six to twelve months later 80% of the initial study group were reassessed, focusing on referrals of the patients with a dependence syndrome to institutions specialized for the treatment of addiction. In most cases these patients were still treated at the previous institution; there were only a few referrals. Improvements concerning the increase of the referral rate to competent specialized institutions for patients with addiction seems possible by implementation of a decentralized consultation liaison service for outpatient departments, hospitals and also private practitioners in a mobile form.

[EMG abnormalities in REM sleep of addicted patients]

EMG abnormalities such as short muscle twitches and marked increase of muscle tone can be identified during REM sleep. We compared the polysomnographic parameters of ten alcoholic patients who were sober and medication-free for at least four weeks, five methadone-substituted politoxicomanic patients (MSP) and ten healthy control patients. The alcoholics and the MSP showed significantly more twitches than the control patients, and the MSP had significantly more tonus increase than the alcoholics and the controlled. The polysomnographic measures differed significantly between the groups in sleep architecture. The alcoholics had significantly less slow-wave sleep (SWS) and more REM sleep, the MSP had a longer REM latency and more of stage 2. Dividing all subjects along the median of the two EMG abnormalities, the group which showed a high number of twitches had significantly less SWS with a compensatory increase of stage 2. The two EMG measures, which were scored additionally, may provide a useful additional information in the differentiation of sleep disturbances in alcoholic and methadone-substituted patients. The interaction between the occurrence of these EMG abnormalities and the other polysomnographic measures in our study needs further clarification.

Drug dependence in patients in psychiatric hospitals in Switzerland. A survey conducted in nine psychiatric hospitals from 1983-1986

The present article forms part of an investigation which has been carried on continuously under the auspices of the Conference of Swiss Sanitary Directors with the aim of providing evidence on the frequency of drug dependence in inpatients of psychiatric hospitals. The investigation is an important source of information concerning trends in drug dependence patterns. In this study, it was possible to observe a change in preference with regard to the use of analgetic compounds over the past years. The decreasing use of barbiturates was found to have been replaced by an increased intake of benzodiazepines. Dependence on heroin has increasingly been observed in recent years. On the whole, multiple drug dependence combined with alcoholism are at present the most frequently observed forms of dependence.

Mental and behavioural disorders due to psychoactive substance use (section F1): results of the ICD-10 field trial

The ICD-10 field trial of section F1 (mental and behavioural disorders due to psychoactive substance use) shows comparatively high acceptance of the new classification in German-speaking countries. Goodness of fit and subjective confidence of the main diagnosis are above average. Analysis of interrater reliability with regard to main diagnostic categories reveal certain problems. The reliability values are flow average within the ICD-10 field study. Possible causes for low interrater reliability are inadequate differentiation from section F0 (organic disorders) and uncertainties in the differential assessment of psychopathological symptoms between F1 and F2, as also between F1 and F4. Interrater reliability could be improved by introducing "psychoactive substance use" as a separate axis in a forthcoming multiaxial scheme for ICD-10.

[Naltrexone--an effective aid in the psychosocial rehabilitation process of former opiate dependent patients]

Naltrexon is an longterm opioid antagonist, which can be used in the psychosocial rehabilitation process of former dependents on opiates. It was established that there were less opiates used during the treatment with Naltrexon. The exclusive delivery of Naltrexon cannot protect from relapse and has to be completed with psychotherapeutic measures.

[Drug-dependent patients in general practice]

Contrary to the popular opinion of many physicians, addicts are primarily seeking help in the practice. The treatment of addicts in the practice requires an early diagnose. The competence of treatment needs a sensible part, concerning the knowledge about the potential of dependence and the following symptoms, the withdrawal medication and the relapse situations, and an emotional part, concerning personal attitude towards personal vulnerability to face relapses. It is desirable to develop liaison services between physicians in practice and the specialists to improve the efficiency of treatment.

[Benefits and risks in using benzodiazepines from the viewpoint of pharmaco-epidemiology with reference to substance dependence]

Anxiety and sleep disturbances are frequent symptoms in medical practice. They still constitute the main indications for prescription patterns. The evaluation of risks and benefits deals with many methodological problems concerning terminology of dependence and pharmaco-epidemiology finally findings in the literature are reviewed under the aspects of diminishing the risk of dependence.

Discrimination of opiate dependence from opiate abstinence and methadone maintenance by use of the Derogatis scale

A sample of opiate addicts from the Basle area followed over six years (1979-1985) was in 1985 investigated concerning psychopathological features. Using the Derogatis scale significant differences between opiate abstinence and opiate dependence could be demonstrated. People still using opiates described themselves as being more obsessive, insecure, depressed, aggressive and anxious than people who had become abstinent from opiates. Patients in methadone maintenance were located in between. There were in addition significant differences between people living outside an institution and people being treated in therapeutic or penal institutions, but no differences between people from each kind of institution.

Benzodiazepine abuse in patients of doctors in domiciliary practice in the Basle area

In the city of Basle with a catchment area of 300,000 inhabitants a significant number of physicians were asked for observations concerning benzodiazepine abuse by their patients. In 1985, 31 patients abusing benzodiazepine only were observed, which represents an incidence of 1:10,000 or 0.01%. In addition, concrete information on 88 patients with multiple abuse was obtained. Demographic data, diagnosis and main reason of abuse, data on most frequently abused drugs, consequences of abuse, as well as measures against the abused are described in relation to the two main groups of abusers.

[Developmental course of opiate-dependent patients over 6 years (1979-1985)]

Drug addicts of the Basle area have been analysed during 6 years in connexion with the National Research Programme 'social integration' and also a following project. The results are contradictory to the pessimism which exists against changes of development of drug addicts.