• The Korean Journal of Physiology
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• v.2 no.1
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• pp.53-58
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• 1968

In order to study the electrocardiogram of small animals authors deviced a fixing apparatus in the ventral resting position of rabbit and an attaching electrodes. Normal electrocardiograms of 8 adult rabbits were studied with author's improved fixing apparatus and electrodes. Leads taken were the standard limb lead, augmented unipolar leads and the unipolar precordial leads. The total numbers of various leads were eleven altogether. Results obtained in this study may be summarized as follows: 1. The details of the methods used to record and measure the six standard frontal plane leads and the five precordial leads of the rabbit electrocardiogram in the ventral resting position were described. The fixing apparatus of rabbits in ventral position are shown in Figure 1 and the attaching electrodes are shown in Figure 2. 2. The electrocardiographic changes in ventral position were more stable than in dorsal position in each lead. 3. The analysis of the amplitude, duration and other values of various waves are shown in Table 1 and Figure 3. 4. The electrocardiogram of rabbits showed decreased heart rate in ventral position than dorsal one. 5. The mean electrical axis of QRS complex in ventral position were +44.12 degrees and in dorsal position were +25.5 degrees.

• The Korean Journal of Physiology
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• v.10 no.1
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• pp.41-48
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• 1976

Tetrodotoxin (TTX) is the purified active principle responsible for tetrodon (Puffer-fish) poisoning which has long been known in the Orient. The pharmacological actions of TTX have been rather extensively investigated. Two of the most prominent effects of intravenousely administered TTX are severe hypotension and respiratory paralysis resulting from its depressant actions on tissues. This depressant actions of TTX in turn result from the selective inhibition of sodium-carrying mechanism which is essential to generation of the action potential. TTX differs from local anesthetics in that it does not affect potassium conductance. Although the mechanism of the hypotensive action of TTX remains a subject of controversy, most investigator agree that TTX-induced hypotension is caused by alteration in the blood vessels rather than the heart. Not only the study on the effects of TTX on cardiac function is meager but the results of reported works are often contradictory. The present study was undertaken to investigate the effect of TTX on the electrocardiogram of the rabbit and to compare them with well known electrocardiographical characteristics found in digitalis and quinidine intoxicated animals. The results obtained from the present study are summarized as follows. 1. No changes were found in P-R interval and QRS duration after i.v. administration of $1.0\;{\mu}g/kg\;to\;1.5\;{\mu}g/kg$ TTX to the animals. It is obvious that there were no conduction disturbance between atria and ventricles as well as in the ventricular tissue. 2. In $1.0\;{\mu}g/kg$ TTX group, S-T interval and T-P segment were not changed whereas marked changes were observed in $1.5\;{\mu}g/kg$ TTX group. 3. The first and second degree A-V blocks appeared in the $2.0\;{\mu}g/kg$ TTX group. 4. TTX differs from digitalis and quinidine in that it does not cause S-T interval depression and T-wave inversion. In contrast with digitalis, TTX caused Q-T interval prolongation.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.191-197
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• 2000

Objectives : Risperidone is a new antipsychotic drug developed to overcome the therapeutic limitation of conventional antipsychotics. It responses to negative as well as positive symptoms by blocking both dopaminergic and serotonergic receptors, causing no significant side effects such as agranulocytosis and seizure. It is, however, not known whether it induces any serious cardiovascular side effects as evoked by other conventional antipsychotic drugs. The aims of this study were to evaluate the effect of risperidone on cardiovascular function, and to discuss the factors affecting the cardiovascular function. Methods : For 42 patients(22 males and 20 females) diagnosed as schizophrenia, schizophreniform disorder or schizoaffective disorder according to the DSM-IV classification, the cardiovascular fuctions such as heart rate, systolic and diastolic blood pressure, PR interval, QRS interval and QT interval were successively checked before and after 2 weeks and 4 weeks risperidone administration. Furthermore, variables such as body weight, Brief Psychiatric Rating Scale(BPRS), Clinical Global Impression(CGI), Extrapyramidal Symptom Rating Scale(ESRS), Anticholinergic Rating Scale(ARS), serum cholesterol level, serum triglyceride level, serum high-density-lipoprotein level, serum WBC, serum Hb, serum platelet level, prothrombin time and partial thromboplastin time were also analyzed before and after 2 weeks and 4 weeks risperidone administration. Results : 1) Risperidone treatment resulted in a significantly decreased heart rate and increased QT interval after 4 weeks administration(p<0.005 respectively). 2) The scores of BPRS and CGI were significantly decreased after 2 weeks and 4 weeks risperidone administration as compared with baseline(p<0.001 respectively). The scores of ESRS and ASRS were significantly increased after 2 weeks and 4 weeks risperidone administration as compared with baseline(p<0.001 respectively). 3) There were positive correlations between heart rate after 4 weeks and total dose(P<0.05). Blood pressure was significantly(p<0.05) correlated with sex(higher in male) and significantly(p<0.05) positive correlated with body weight. QT interval was significantly(p<0.05) correlated with sex(longer in female) and smoking history(shorter in smokers). Conclusions : Risperidone could induce significant change in heart rate and Q-T interval. Therefore, the cardiovascular safety for risperidone should be reconsidered according to the duration and dosage increase.

• Journal of The Korean Society of Clinical Toxicology
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• v.8 no.2
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• pp.97-105
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• 2010

Purpose: Although cardiac toxicity is a key parameter of significant toxicity, in antidepressant intoxication, there are few studies on the cardiac toxicity of serotonin reuptake inhibitor and the intoxication with the new generation of antidepressants. The aim of this study is to investigate the relative cardiac toxicity of serotonin reuptake inhibitor and intoxication with the new generation of antidepressants as compared with that of tricyclic antidepressant intoxication. Methods: We retrospectively reviewed the medical records of 109 antidepressant intoxicated patients who visited the Emergency Department from January, 2005 to December, 2009 to collect and analyze the demographic and clinical data. Sixteen patients were excluded. The enrolled seventy eight patients were classified into three groups: the tricyclic antidepressant group (TCA) (n=32), the selective serotonin reuptake inhibitor subgroup (SSRI) (n=28) and the new generation antidepressant subgroup (NGA) (n=18). Results: The demographic and clinical data of the SSRI and NGA groups were not significantly different from that of the TCA group. The QRS duration of the SSRI subgroup ($86.4{\pm}12.0$ msec) and the NGA subgroup ($91.8{\pm}11.9$ msec) was not significantly different from that of the TCA group ($90.0{\pm}13.5msec$) (p=0.598). The QTc interval of the SSRI group ($444.5{\pm}33.5msec$) and the NGA group ($434.9{\pm}35.9msec$) (p=0.260) were not significantly different from that of the TCA group ($431.2{\pm}44.1msec$) (p=0.287). Conclusion: Intoxication with SSRI and the new generation antidepressants seemed to show significant cardiac toxicity, like what is seen in tricyclic antidepressant intoxication. Clinicians must pay attention to SSRI and new generation antidepressant intoxication.

• Korean Circulation Journal
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• v.48 no.11
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• pp.1002-1011
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• 2018

Background and Objectives: The prognostic impact of left axis deviation (LAD) on clinical outcomes in acute heart failure syndrome (AHFS) with left bundle branch block (LBBB) is unknown. The aim of this study was to determine the prognostic significance of axis deviation in acute heart failure patients with LBBB. Methods: Between March 2011 and February 2014, 292 consecutive AHFS patients with LBBB were recruited from 10 tertiary university hospitals. They were divided into groups with no LAD (n=189) or with LAD (n=103) groups according to QRS axis <-30 degree. The primary outcome was all-cause mortality. Results: The median follow-up duration was 24 months. On multivariate analysis, the rate of all-cause death did not significantly differ between the normal axis and LAD groups (39.7% vs. 46.6%, adjusted hazard ratio, 1.01; 95% confidence interval, 0.66, 1.53; p=0.97). However, on the multiple linear regression analysis to evaluate the predictors of the left ventricular ejection fraction (LVEF), presence of LAD significantly predicted a worse LVEF (adjusted beta, -3.25; 95% confidence interval, -5.82, -0.67; p=0.01). Right ventricle (RV) dilatation was defined as at least 2 of 3 electrocardiographic criteria (late R in lead aVR, low voltages in limb leads, and R/S ratio <1 in lead V5) and was more frequent in the LAD group than in the normal axis group (p<0.001). Conclusions: Among the AHFS with LBBB patients, LAD did not predict mortality, but it could be used as a significant predictor of worse LVEF and RV dilatation (Trial registry at KorAHF registry, ClinicalTrial.gov, NCT01389843).

• Korean Journal of Psychosomatic Medicine
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• v.28 no.1
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• pp.63-71
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• 2020

Objectives : The aim of this study was to investigate the impact of clinical and psychological factors on the parental stress of children and adolescents with epilepsy. Methods : Children and adolescents with epilepsy (n=90, age range=6-17 years) completed questionnaires on epilepsy-related variables, children's depressive symptoms (Children's Depression Inventory, CDI), children's anxiety (Revised Children's Manifest Anxiety Scale, RCMAS) and performed the scale for children's intelligence (IQ). Parents who have children and adolescents with epilepsy completed questionnaires on parental stress (Questionnaire on Resources and stress, QRS), parental anxiety (State-Trait Anxiety Inventory, STAI), children's attention problems (Abbreviated Conners Parent Rating Scale Revised, CPRS), and children's behavioral problems (Korean Child Behavior Checklist, K-CBCL). Stepwise regression analysis was performed to determine the significant predictive variables that affect parental stress. Results : In the correlational analysis, duration of seizure treatment (r=0.253, p=0.016), children's IQ (r=-0.544, p<0.001), children's attention problems (r=0.602, p<0.001), children's depressive symptoms (r=0.335, p=0.002), children's anxiety (r=0.306, p=0.004), children's behavioral problems (r=0.618, p<0.001), and parental anxiety (r=0.478, p<0.001), showed a significant correlation with parental stress. Children's behavioral problem (β=0.241, p=0.010), children's IQ (β=-0.472, p<0.001), and parental anxiety (β=0.426, p<0.001) were significantly related to the parental stress (Adjusted R²=0.619). Conclusions : Clinicians should pay attention to children's intelligence and behavioral problems and parental anxiety, which affect parental stress with children and adolescents with epilepsy.