Biomedical subjects

T Korte

Publications and source records attributed to T Korte.

At least 37 records · Page 2Linked to original sources

PubMed2000

Absorption and hemodynamic effects of airway administration of adrenaline in patients with severe cardiac disease.

BACKGROUND: If intravenous access cannot be attained during resuscitation of adult patients, endotracheal application of at least 2 mg of adrenaline is recommended. However, the effects of this intervention have not yet been demonstrated in adults. OBJECTIVE: To demonstrate the effects of adrenaline administered through the airways. DESIGN: Prospective clinical trial. SETTING: Operating theater at university hospital. PATIENTS: 34 patients receiving implantable cardioverter defibrillators under general anesthesia. INTERVENTION: When mean arterial pressure decreased below 80 mm Hg, 100 times the effective central intravenous dose of adrenaline (mean +/- SD, 1.3+/-0.6 mg [range, 0.7 to 3 mg]) was administered over 5 seconds into the endotracheal tube or through a bronchial catheter. Ten forced ventilations followed. MEASUREMENTS: Hemodynamic variables were recorded with a polygraph recorder. Adrenaline levels were measured in 13 patients. RESULTS: Plasma levels and arterial pressure increased in all patients (P < 0.002). Higher plasma levels (P < 0.039) and greater arterial pressure (P < 0.001) were achieved with this method than with intravenous injection. The effects of adrenaline did not differ between the two airway routes. Sustained ventricular arrhythmia did not occur. CONCLUSION: These substantial effects support the standard recommendation to consider the airways as an alternate route for at least 2 mg of adrenaline during resuscitation.

Absorption↗

PubMed2000

[A new ICD morphology criterion for differentiating supraventricular and ventricular tachycardia].

The high incidence of inappropriate therapies due to supraventricular tachycardia remains a major unsolved problem of the implantable cardioverter defibrillator. A new morphology discrimination (MD) algorithm has been introduced to improve specificity of ICD therapy without loss of sensitivity. It was the aim of this study to systematically analyze sensitivity and specificity of the MD criterion in combination with the enhanced detection criteria sudden onset and rate stability in the detection of ventricular and supraventricular tachycardia. After ICD implantation in 259 patients, 787 detected episodes in 74 patients with available stored electrograms were documented during a follow-up period of 359 +/- 214 days. With a nominal programming of the MD algorithm at > or = 60%, sensitivity and specificity for all episodes were 82.6%/77.2%. For sinus tachycardia, atrial fibrillation and atrial flutter the specificities were 80.6%, 69.6% and 75%, respectively. In patients with primarily appropriate MD detection, sensitivity and specificity significantly improved to 95.8%/91.7%. Programming the sudden onset criterion with < 100 ms and the stability criterion with < 50 ms, sensitivity and stability of the combined application of the MD algorithm and sudden onset and MD algorithm and stability were 96.2%/52.2% and 94.4%/63.8%, respectively. The MD criterion in combination with other enhanced detection criteria might significantly improve specificity of tachyarrythmia detection of ICD therapy.

Aged↗

PubMed2000

[Implantable cardioverter/defibrillator: long-term stability of the defibrillation threshold with a unipolar electrode configuration (active-can")].

The majority of cardioverter/defibrillator (ICD) implantations are currently performed with a non-thoracotomy approach. From November 1993 to January 1995, 46 patients underwent implantation of a PCD 7219C with an "active-can" lead configuration at our institution. While the chronic stability of the defibrillation threshold (DFT) for an epicardial lead system is well established, the results are still inconsistent for non-thoracotomy lead systems. Accordingly, the aim of the present study was to compare the acute and chronic defibrillation thresholds of the ICDs implanted with an "active-can" lead system in order to assess the chronic stability of these systems. The defibrillation energy requirements were measured at implant, prior to hospital discharge, three, six and twelve months after implantation of the defibrillator. The patient group consisted of 8 females and 38 males with a mean age of 57.2 years. The mean left ventricular ejection fraction was 43.8%. The most frequent underlying heart disease was coronary artery disease in 31 of 46 patients. Eight patients had idiopathic dilated cardiomyopathy. In 39 of 46 patients, the defibrillation threshold could be successfully determined at all 4 time points after implantation. The mean defibrillation energy requirement at the time of implantation was 9.2 +/- 5.9 Joules (J). The subsequent mean energy requirements were 7.6 +/- 4.8 J at pre-hospital discharge, 8.6 +/- 5.7 J at the 3 month, 8.1 +/- 6.0 J at the 6 month and 8.6 +/- 5.8 J at the 12 month follow-up visits. The mean defibrillation threshold was lowest at the time of prehospital discharge, significantly lower than at the time of initial implantation (p = 0.021). However, at all later time points up to one year, there was no significant difference in the DFT as compared with the time of initial implantation. Comparing the DFT at the time of implantation and the DFT at all other time points, there were no significant differences (9.23 vs. 8.56 J, p = 0.291). Although there was an initial decrease in the DFT at seven to ten days, the long-term stability of the DFT up to one year remained stable in the devices with the "active-can" lead system.

Adult↗

PubMed2000

Hospital readmission after transvenous cardioverter/defibrillator implantation; a single centre study.

AIMS: Hospital readmission after implantation of cardioverter/defibrillators has a major impact on quality of life and cost-effectiveness in defibrillator patients. Rehospitalization has not been studied in large patient populations with modern transvenous defibrillation systems. METHODS AND RESULTS: We report on incidence, reasons, time in follow-up, duration and predictors of hospital readmission in 180 patients after transvenous implantation of a cardioverter/defibrillator during a follow-up period of 25+/-18 months. There were 156 readmissions in 79 patients with a 0.87 readmission rate per patient during the time followed, a 0.46 readmission rate per patient-year of follow-up and a 0.38 readmission rate per patient-year of follow-up for cardiac reasons. The majority of readmissions was caused by multiple appropriate shock interventions (26%), battery depletion (19%) and lead- and device-related complications (14%). The time to first hospital readmission was 12+/-9 months for arrhythmia-related and 20+/-16 months for other cardiac-related reasons (P<0.05), and could not be predicted by clinical variables, respectively. The duration of rehospitalization was 14+/-15 days for cardiac-related reasons and 12+/-17 days for arrhythmia-related reasons. Age >60 years was an independent predictor of rehospitalization time per patient-year of follow-up for both cardiac-related (P<0.005) and arrhythmia-related reasons (P<0.05). CONCLUSION: The rate of hospital readmission per patient-year of follow-up is as high as 0.46 after implantation of a modern cardioverter/defibrillator. Rehospitalization time in such patients is significantly longer in the patient cohort >60 years. The majority of readmissions is caused by multiple appropriate shock treatments. Further studies are needed to systematically investigate strategies for the prevention of rehospitalization in modern ICD therapy.

Adolescent↗

PubMed2000

Bimodal RR interval distribution in chronic atrial fibrillation: impact of dual atrioventricular nodal physiology on long-term rate control after catheter ablation of the posterior atrionodal input.

INTRODUCTION: Radiofrequency (RF) catheter modification of the AV node in patients with atrial fibrillation (AF) is limited by an unpredictable decrease of the ventricular rate and a high incidence of permanent AV block. A bimodal RR histogram has been suggested to serve as a predictor for successful outcome but the corresponding AV node properties have never been characterized. We hypothesized that a bimodal histogram indicates dual AV nodal physiology and predicts a better outcome after AV node modification in chronic AF. METHODS AND RESULTS: Thirty-seven patients were prospectively subdivided into two groups according to the RR histogram of 24-hour ECG monitoring. Before to RF ablation, internal cardioversion and programmed stimulation were performed. Among the 22 patients (group I) with a bimodal RR histogram, dual AV nodal physiology was found in 17 (77%) patients. Ablation significantly decreased ventricular rate with loss of the peak of short RR cycles after ablation (mean and maximal ventricular rates: 32% and 35% rate reduction, respectively; P < 0.01). In 15 patients with a unimodal RR histogram (group II), dual AV nodal physiology was found in 2 (13%), and rate reductions were 16% and 17%, respectively. At 6 months, 3 (14%) patients in group I and 6 (40%) in group II underwent elective AV nodal ablation with pacemaker implantation due to intolerable rapid ventricular response to AF. CONCLUSION: Bimodal RR interval distribution during chronic AF suggests the presence of dual AV nodal physiology and predicts a better outcome of RF ablation of the posterior atrionodal input.

Adult↗

PubMed2000

Glycosphingolipids promote entry of a broad range of human immunodeficiency virus type 1 isolates into cell lines expressing CD4, CXCR4, and/or CCR5.

Treatment of human osteosarcoma cells, expressing CD4 and various chemokine receptors, with the glucosylceramide synthase inhibitor 1-phenyl-2-hexadecanoylamino-3-morpholino-1-propanol (PPMP), blocked target membrane glycosphingolipid (GSL) biosynthesis and reduced the susceptibility of cells to infection and fusion mediated by envelope glycoproteins from a variety of human immunodeficiency virus type 1 (HIV-1) isolates that utilize CXCR4 and/or CCR5. PPMP treatment of the cell lines did not significantly change the cell surface expression of CD4, CXCR4, and/or CCR5, nor did it alter the chemokine receptor association with CD4. PPMP-treated cells exhibited no changes in chemokine-induced Ca(2+) mobilization and chemotaxis. However, massive envelope glycoprotein conformational changes triggered by CD4 and the appropriate chemokine receptor on the target membrane were inhibited when the target cells were treated with PPMP. Addition of various purified GSLs to PPMP-treated target cells showed that for all isolates tested, globotriaosylceramide (Gb3) was the most potent GSL in restoring the fusion susceptibility of target cells with cells expressing HIV-1 envelope glycoproteins; addition of the monosialoganglioside GM3 yielded a slight enhancement of fusion susceptibility. Our data are consistent with the notion that a limited number of specific GSL species serve as crucial elements in organizing gp120-gp41, CD4, and an appropriate chemokine receptor into a membrane fusion complex.

3T3 Cells↗

PubMed2000

Contamination of carcasses, offals, and the environment with yadA-positive Yersinia enterocolitica in a pig slaughterhouse.

This study was carried out in order to evaluate the contamination of the pig-slaughtering line with pathogenic Yersinia enterocolitica carrying the yadA gene. A total of 292 samples were collected from the slaughterhouse; 131 swab samples from pig carcasses, ears, livers, kidneys, and hearts; 89 swab samples from the environment; and 72 sedimentation samples from the air. All surface samples were studied with both the polymerase chain reaction (PCR) and culture methods. The contamination rate of edible pig offals was high with both methods. Using PCR, the detection rates of yadA-positive Y. enterocolitica for livers, kidneys, and hearts were 38, 86, and 63%, respectively, and using the culture method, the detection rates were 31, 69, and 50%, respectively. Pathogenic Y. enterocolitica was also detected from different environmental sites in the slaughterhouse. Using PCR, 13% of the surface samples from the environment were contaminated with yadA-positive Y. enterocolitica. PCR-positive samples were found on the brisket saw, the hook from which the pluck set (heart, lungs, esophagus, trachea, diaphragm, liver, kidneys, and tongue with tonsils) hang, the knife used for evisceration, the floors in the eviscerating area and the weighing area, the meat-cutting table, the aprons used by trimming workers, the computer used in the meat-inspection area, and the coffeemaker used by slaughterhouse workers. The respective detection rate (6%) was considerably lower when we used the culture method. Pathogenic Y. enterocolitica was isolated from the air in the bleeding area. Bioserotype 4/O:3 was the only pathogenic bioserotype isolated in this study. A total of 113 isolates of type 4/O:3 were characterized with pulsed-field gel electrophoresis using NotI and XbaI digests. By combining these profiles, nine different pulsotypes were obtained, the most common of which (1a) was found in 19 (61%) of 31 samples from different sites. This is the same type that has dominated in pig tonsils, which suggests that tonsils may be the source of Y. enterocolitica contamination in the slaughterhouse. The four pulsotypes (1a, 4g, 6g, and 19q) found on edible offals were the same as those found in tonsils, which supports our hypothesis that tonsils are the contamination source for the liver, heart, and kidneys.

Abattoirs↗

PubMed1999

Noninvasive diagnosis in patients with undocumented tachycardias: value of the adenosine test to predict AV nodal reentrant tachycardia.

INTRODUCTION: Patients with symptoms suggestive of paroxysmal supraventricular tachycardia (PSVT) but no tachycardia documentation often undergo diagnostic electrophysiologic study. In dual AV node physiology with AV node reentrant tachycardia (AVNRT), the anterograde fast pathway is more sensitive than the slow pathway to the effects of adenosine. The purpose of the study was to test the hypothesis that adenosine can be used as a bedside test for the diagnosis of dual AV node physiology and hence for AVNRT. METHODS AND RESULTS: During electrophysiologic study, 37 patients without prior documentation but symptoms indicative for PSVT received incremental dosages of adenosine during sinus rhythm until second-degree or greater AV block was observed. Suggestive signs of dual AV node physiology on the surface ECG (sudden jump of PQ interval > or = 50 msec) were found in 13 (76%) of 17 patients with inducible AVNRT but in only 1 (5%) of the remaining patients (P < 0.01). In the AVNRT group, the maximal increase of the PQ interval between two beats was greater (88+/-45 msec) than in the remaining 20 patients (17+/-11 msec) (P < 0.01). CONCLUSION: Careful evaluation of surface ECG during administration of adenosine helps to identify patients prone to AVNRT. The adenosine test is a valuable noninvasive adjunct in patients with undocumented palpitations suggestive of PSVT.

Adenosine↗

PubMed1999

Conformational intermediates and fusion activity of influenza virus hemagglutinin.

Three strains of influenza virus (H1, H2, and H3) exhibited similar characteristics in the ability of their hemagglutinin (HA) to induce membrane fusion, but the HAs differed in their susceptibility to inactivation. The extent of inactivation depended on the pH of preincubation and was lowest for A/Japan (H2 subtype), in agreement with previous studies (A. Puri, F. Booy, R. W. Doms, J. M. White, and R. Blumenthal, J. Virol. 64:3824-3832, 1990). While significant inactivation of X31 (H3 subtype) was observed at 37 degrees C at pH values corresponding to the maximum of fusion (about pH 5.0), no inactivation was seen at preincubation pH values 0.2 to 0.4 pH units higher. Surprisingly, low-pH preincubation under those conditions enhanced the fusion rates and extents of A/Japan as well as those of X31. For A/PR 8/34 (H1 subtype), neither a shift of the pH (to >5.0) nor a decrease of the temperature to 20 degrees C was sufficient to prevent inactivation. We provide evidence that the activated HA is a conformational intermediate distinct from the native structure and from the final structure associated with the conformational change of HA, which is implicated by the high-resolution structure of the soluble trimeric fragment TBHA2 (P. A. Bullough, F. M. Hughson, J. J. Skehel, and D. C. Wiley, Nature 371:37-43, 1994).

Anilino Naphthalenesulfonates↗

PubMed1998

Drug abuse of Finnish male prisoners in 1995.

The purpose of the present research was to estimate the extent and variety of abuse of illegal drugs, use and misuse of hypnotics and sedatives and anabolic steroids in the Finnish prison population. The study was undertaken during October-November 1995 at four prisons, three of which were closed institutions and one an open prison; one of the three closed institutions was a juvenile prison. There was a total of 707 inmates in the prisons selected for the study. Questionnaires were given personally to all prisoners in the open prison and in the young prisoners' division in the juvenile prison, but in two large central prisons only some divisions were selected for the study. The questionnaires were completed by 354 prisoners; 75 prisoners refused to respond. A total of 27.7% of subjects reported taking illegal drugs while in their current prison and 70.1% had sometimes used them. Of those who were drug-free before their first imprisonment, 21.7% began using drugs in prison. At present hypnotics and sedatives were reported as in use by 41.8% of subjects, one-third as prescribed drugs and about 10% illicitly. A total of 3.7% of subjects reported taking anabolic steroids in the current prison. Cannabis and amphetamine were the most common illegal drugs reported. Intravenous drug use was reported by 19.2% of the respondents at some point in their lives, and 10.7% of prisoners had injected drugs in their current prison. Use of illegal drugs and misuse of drugs were significantly higher among young prisoners (< or = 25 years of age).

Adolescent↗

PubMed1998

Conformational changes in cell surface HIV-1 envelope glycoproteins are triggered by cooperation between cell surface CD4 and co-receptors.

We have continuously measured CD4-induced conformational changes of cell surface-expressed human immunodeficiency virus type-1 envelope glycoprotein gp120-gp41 in situ using 4,4'-dianilino-1, 1'-binaphthyl-5,5'-disulfonic acid, a fluorescent probe that binds to hydrophobic groups. CD4-expressing human T cell lines induced significant and rapid conformational changes (<1 min delay) in gp120-gp41 from T cell-tropic strains, and little conformational changes in gp120-gp41 from macrophage-tropic strains, with equivalent levels of envelope expression. Conversely, CD4-expressing human macrophages induced significant and rapid conformational changes in gp120-gp41 from macrophage-tropic strains, and little conformational changes in gp120-gp41 from T cell-tropic strains. Thus, the conformational changes undergone by gp120-gp41, which lead to membrane fusion, are highly cooperative and require both receptor and co-receptor. We used a dye transfer assay to show that neither membrane lipid fusion or fusion pore formation can occur with host cells having different tropism from the envelope.

Anilino Naphthalenesulfonates↗

PubMed1998

Small molecule inhibitor of HIV-1 cell fusion blocks chemokine receptor-mediated function.

The intersection of the HIV and the chemokine fields began with the observation that HIV entry into cells could be blocked by certain chemokines. Subsequent work showed that HIV entry is dependent on the presence of specific chemokine receptors. These observations led us to evaluate a series of compounds, ureido analogs of distamycin previously reported to block HIV entry into cells in vitro, for chemokine antagonist activity. One of the distamycin analogs, 2,2'[4,4'-[[aminocarbonyl]amino]bis[N,4'-di[pyrrole-2-carboxamide- 1,1'-dimethyl]]-6,8 napthalenedisulfonic acid] hexasodium salt (NSC 651016), is shown here to inhibit syncytia formation and cell fusion. Mechanistic studies showed that this inhibition was not due to conformational changes in gp120-gp41 induced by target cell CD4 and chemokine co-receptor and was therefore not due to interference with binding of HIV-1. Additional mechanistic studies demonstrated that NSC 651016 inhibited chemokine binding to specific chemokine receptors, induced CXCR4 and CCR5 receptor internalization, and inhibited chemokine-induced chemotaxis by macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, RANTES, and stromal-derived factor-1alpha but not monocyte chemotactic protein-1. Thus, we describe a novel compound that inhibits in vivo replication of HIV-1 by down-regulation of co-receptors. These data lead us to propose that NSC 651016 may have in vivo anti-inflammatory activity.

Anti-HIV Agents↗

PubMed1998

Prospective evaluation of shoulder-related problems in patients with pectoral cardioverter-defibrillator implantation.

BACKGROUND: The pectoral approach to implantation of cardioverter defibrillators (ICDs) has become a standard in defibrillator therapy because of reduced generator size, weight, and volume. But the size of these devices is still comparable to the size of the early conventional antibradycardia pacemakers that were associated with a number of significant pocket- and shoulder-related problems after implantation in the pectoral region. In a prospective, single-center study of 50 patients with subpectoral implantation of a fourth-generation ICD, the ipsilateral shoulder joint was evaluated regarding active shoulder motility, shoulder-related pain, shoulder function, shoulder elevation, insertion tendinitis, and morphologic alterations of the shoulder. METHODS AND RESULTS: The shoulder was evaluated before implantation and at 3, 6, and 12 months after implantation. Shoulder motility was documented by evaluating active abduction, forward flexion, and external rotation. Shoulder-related pain and function were documented by the "Basic Shoulder Evaluation Form," insertion tendinitis was diagnosed by standardized palpation and the impingement test, and morphologic alterations were documented by ultrasound and radiograph of the shoulder. Three months after implantation, 20 (40%) patients had a reduced active abduction, 30 (60%) patients had an impaired active forward flexion, and eight (16%) patients had a reduced external rotation. Thirty-one (62%) patients reported shoulder-related pain or impaired shoulder function according to the "Basic Shoulder Evaluation Form." Twenty-four (48%) patients showed a shoulder elevation and 21 (42%) patients demonstrated clinical signs of insertion tendinitis. After 12 months the number of patients with reduced active abduction, forward flexion, and external rotation dropped to four (8%). Shoulder-related pain and reduced function were documented in seven (13%) patients, four (8%) patients still had shoulder elevation, and five (10%) patients still had signs of insertion tendinitis. None of the postoperatively performed ultrasounds or radiographs showed any pathologic shoulder alterations. No predictors for the occurrence of shoulder-associated problems could be found. CONCLUSIONS: (1) Decreased active shoulder motility, shoulder-related pain, reduced function, shoulder elevation, and insertion tendinitis of the ipsilateral shoulder joint are diagnosed in many patients 3 months after subpectoral ICD implantation. (2) After 12 months the number of patients with impaired shoulder motility, function, shoulder-related pain, shoulder elevation, and insertion tendinitis decreased significantly. (3) Ultrasound and radiographs of the ipsilateral shoulder showed no evidence of pathologic morphologic alterations after subpectoral ICD implantation. (4) No shoulder-associated problems required an operative revision of the subpectoral generator pocket.

Defibrillators, Implantable↗

PubMed1998

Case report: inappropriate discharge of an implantable cardioverter-defibrillator caused by the combined count criterion.

We describe a rare case of an inappropriate defibrillator discharge during a sinus tachycardia with single fast sensed beats fulfilling the ventricular fibrillation rate criterion, activating the "combined count criterion," although the prevalent sinus tachycardia was inside a ventricular tachycardia rate zone, programmed to monitor only mode. The "combined count criterion" is a safety feature that ensures defibrillation therapy in case of a tachyarrhythmia inside the ventricular tachycardia detection zone, that is temporarily crossing the ventricular fibrillation detection rate. This case reports shows that there is a low but unpredictable risk of device therapy even in a zone programmed to monitor only mode. This phenomenon should be considered when a monitor only zone is installed for revelation of slower tachyarrhythmias.

Adult↗

PubMed1998

A new classification algorithm for discrimination of ventricular from supraventricular tachycardia in a dual chamber implantable cardioverter defibrillator.

INTRODUCTION: The high incidence of inappropriate therapies due to supraventricular tachycardia remains a major unsolved problem of implantable cardioverter defibrillators. We report a new detection formula for discrimination of ventricular tachycardia from supraventricular tachycardia in a patient with a dual chamber implantable cardioverter defibrillator and a new atrioventricular classification algorithm. METHODS AND RESULTS: The enhanced detection algorithm performs a stepwise arrhythmia analysis. The rhythm is first classified on the basis of cycle length. Each episode is then classified as supraventricular or ventricular on the basis of atrioventricular association, stability of circle length, and origin of acceleration. Sophisticated diagnostic information is provided by atrioventricular markers and electrogram recordings. Successful discrimination of two spontaneous episodes of ventricular tachycardia and supraventricular tachycardia is demonstrated. CONCLUSION: This new dual chamber detection algorithm may significantly improve the specificity of tachyarrhythmia detection without sacrificing sensitivity, thereby reducing the number of spurious shocks in patients with recurrent supraventricular tachycardias. Further studies are needed to assess the sensitivity and specificity of this detection algorithm.

Algorithms↗

PubMed1997

Transient changes of the conformation of hemagglutinin of influenza virus at low pH detected by time-resolved circular dichroism spectroscopy.

Membrane fusion of influenza virus is mediated by a conformational change of the viral membrane protein hemagglutinin (HA) triggered by low pH. By near UV CD spectroscopy, which is sensitive to the arrangement and mobility of aromatic amino acids in proteins, we have monitored continuously with a time resolution of 5 s the kinetics of structural alterations of the ectodomain of HA isolated from different influenza virus strains (H1 (A/PR 8/34), H2 (A/Japan), and H3 (X31)). To establish a functional correlation to structural alterations of the HA ectodomain reflected by the CD, we have measured the kinetics of the virus-erythrocyte fusion and of the inactivation of fusion by low pH preincubation of viruses. At acidic pH we found a multiphasic behavior of the CD signal recorded at 283 nm. Upon lowering the pH we detected first an increase of the CD amplitude, which is associated with the formation of a fusion-competent state of HA. The initial increase was followed by a continuous decline of CD amplitude, which can be ascribed to a transformation into a fusion-inactivated conformation that is in its early phase reversible as found for A/Japan. The half-time of the different phases of the CD signal depended on the virus strain, the temperature, and the acidic pH. The results support recent hypotheses that the fusion-competent conformation is an intermediate of the fusion-inactivated structure of HA.

Circular Dichroism↗

PubMed1997

Radiofrequency catheter ablation of atrial flutter that elicits inappropriate implantable cardioverter defibrillator discharge.

The case of a patient with recurrent VT and an ICD is reported. After appropriate device discharges, the patient experienced 40 episodes of inappropriate shock therapy due to atrial arrhythmias confirmed as type I atrial flutter. Since programmed stimulation could reliably initiate atrial flutter, catheter ablation was performed. During delivery of RF current, atrial flutter terminated and was no longer inducible. The patient had no further inappropriate device discharges during 12 months of follow-up. In patients with ICDs suffering from recurrences of atrial flutter leading to inappropriate shock therapy, RF catheter ablation is an effective and curative approach.

Atrial Flutter↗

PubMed1996

Comprehensive drug screening in blood for detecting abused drugs or drugs potentially hazardous for traffic safety.

A comprehensive drug screening procedure for detecting drugs in the blood samples of car drivers suspected of driving under the influence of drugs, is presented. Amphetamines, cannabinoids, opioids, cocaine and benzodiazepines were screened by an immunological EMIT ETS system after acetone precipitation. Gas chromatographic methods were used to screen and quantitate basic, neutral and acidic drugs. The free amino groups of basic drugs were derivatized with heptafluorobutyric anhydride. Analysis was performed by a dual channel gas chromatograph combined with a nitrogen phosphorus and an electron capture detector. Phenyltrimethylammonium hydroxide was used as a methylathing agent for acidic substances before analysis with a gas chromatograph connected to a nitrogen phosphorus detector. A gas chromatograph/mass spectrometry was used as a common confirmation method. Tetrahydrocannabinol was quantitated after bis(trimethylsilyl)trifluoroacetamide derivatization, opiates after pentafluoropropionic anhydride derivatization and benzoylecgonine after pentafluoropropionic anhydride and pentafluoropropanol derivatization. Excluding benzodiazepines, which were confirmed with a gas chromatograph connected to a nitrogen phosphorus and an electron capture detector, the other basic drugs as well as the acidic drugs were confirmed after the same derivatization procedures as in the screening methods. Alcohols were quantitated in triplicate by gas chromatography using three different kinds of columns. Although urine is the most important specimen for screening abused drugs, it has only limited use in forensic toxicology. The described system is most useful for analyzing a wide range of substances, including illicit drugs, benzodiazepines, barbiturates, antidepressants and phenothiazenes in forensic samples when urine is not available.

Accidents, Traffic↗