Double-blind randomised controlled trial of lofexidine versus clonidine in the treatment of heroin withdrawal

Lofexidine is an analogue of clonidine, an agonist at the alpha 2 noradrenergic receptor. Reports from preliminary open studies have suggested that it may be at least as effective as clonidine in the management of opiate withdrawal, and without the same limitation of postural hypotension. We report on a randomised double-blind comparison of lofexidine versus clonidine in the treatment of heroin withdrawal. A total of 80 hospitalized heroin addicts were randomly assigned to treatment with lofexidine or clonidine during in-patient opiate withdrawal. Maximum daily doses were 1.6 mg for lofexidine and 0.6 mg for clonidine. There was marked diurnal variation of withdrawal symptoms with severity being greatest at the daytime reading at 16.00 h and being markedly less at the night-time reading (recorded at 08.00 h). Lofexidine and clonidine were equally effective in treating the withdrawal syndrome. However, significantly more problems relating to hypotension were encountered with subjects on clonidine, with twice as many instances of withholding medication due to hypotension in the clonidine group. Better treatment retention rates were seen in the lofexidine group, although no difference was found in the proportion who had reached minimal symptom severity by the time of their discharge. We conclude that lofexidine and clonidine are equally effective, but with significantly fewer hypotensive problems with lofexidine. Further benefit from lofexidine may be possible with revised dosing regimens. Outpatient studies of lofexidine are now indicated.

Dose-dependent reduced haloperidol/haloperidol ratios: influence of patient-related variables

Plasma reduced haloperidol (RH) concentrations or RH to haloperidol (HL) ratios have been suggested to be important in determining the clinical efficacy and extrapyramidal side effects of HL. In this study, we measured the steady-state plasma HL and RH levels by high performance liquid chromatography and analyzed the effects of various variables (dose, gender, age, and body weight) on RH/HL ratios in four dose groups of Chinese schizophrenic inpatients: 10 mg/day (n = 84), 20 (n = 111), 30 (n = 29), and 60 (n = 55). In addition, the polymorphic distribution of RH/HL ratios, suggested by previous investigators, was further tested in each dosage group (for controlling the potential dosage effect on RH/HL ratios). As a result, both age and body weight could influence RH/HL ratios. Each year increase in age (after adjusting the effects of gender, body weight, and dosage) would elevate the RH/HL ratio by 0.0067 (P < 0.0001). On the other hand, after adjusting gender, age, and dosage effects, each kg increment in body weight would decrease the RH/HL ratio by 0.0044 (P < 0.01). Gender did not influence the ratio. Furthermore, the high dosage groups had higher RH/HL ratios (even with other variables being controlled). In comparison with the 10 mg group, the 60 mg group exhibited a higher mean RH/HL ratio by 0.84 (P < 0.0001) and the 30 mg group did by 0.31 (P < 0.0001). The 20 mg group was almost equal to the 10 mg group in RH/HL ratios. Besides, at each dosage group, the frequency distribution of RH/HL ratios seemed to be predominantly unimodal with a small proportion of extreme outliers. The results of this study clearly indicate that aging or a high dose (> or = 30 mg/day) of HL could raise the plasma RH/HL ratio, while an increasing body weight would reduce that. In contrast, gender does not affect the ratios.

Clozapine dosages and plasma drug concentrations

Steady-state plasma concentrations of clozapine and its metabolites, desmethylclozapine and clozapine-N-oxide, were measured in 162 Taiwanese patients with refractory schizophrenia. The daily doses of clozapine ranged from 100 to 900 mg, with a mean value of 379.5 +/- 142.2 mg. A dosage of 400 mg/day or lower was used for most patients (n = 131, 81%). Plasma concentrations of clozapine and its two major metabolites were measured using high performance liquid chromatography with ultraviolet detection. The mean plasma clozapine concentration was 566.9 +/- 398.8 ng/mL. The plasma concentrations of desmethylclozapine and clozapine-N-oxide were 46% and 16% of the concentration of the parent drug, respectively. We used an approximate rule that each 100 mg/day dose results in about 150 ng/mL plasma clozapine. This value is about 30% to 50% higher than that reported in Caucasians. The suggested therapeutic plasma clozapine concentration range of 300 to 700 ng/mL can be achieved with a dose range of 200 to 500 mg/day in most Taiwanese patients. Dose-dependent plasma clozapine concentrations were found. The interpatient variation was up to 12-fold in patients receiving the same dose, eg, 400 mg/day (n = 62). In four of these patients, the plasma drug concentrations were very high (1,446 +/- 114 ng/mL). The application of therapeutic drug monitoring in clozapine-treated patients with refractory schizophrenia is important, not only in dose adjustment, prediction of severe side effects such as seizures, and exploration of drug interactions, but also in the effective use of this expensive drug.

Histamine 2 receptor blocker-ranitidine and sinus node dysfunction

BACKGROUND

Histamine 2 (H2) receptors were observed to be present in the sinus node. H2 receptor blockers could attenuate the histamine-induced increase in sinus rate and could thereby worsen sinus node dysfunction. However, the data pertaining to electrophysiological effects of H2 receptor blocker ranitidine on sinus node function are not available as yet, although bradycardia has been occasionally reported along with ranitidine. The present study evaluates the electrophysiological effects of ranitidine on sinus node function, and also determines the safety of administering ranitidine to patients suffering from sinus node dysfunction.

METHODS

Thirty-nine patients with clinical diagnosis of sinus node dysfunction were selected for this study. Electrophysiological effects of intravenous injection of 150 mg ranitidine on sinus node function was evaluated. Tests were performed for 21 patients in the basal state (Group 1) and for 18 patients (Group 2) after autonomic blockade (propranolol 0.2 mg/kg, and atropine 0.04 mg/kg). The sinus cycle length (SCL), sinus node recovery time (SNRT), corrected sinus node recovery time (CSNRT), sinoatrial conduction time (SACT), atrio-His (AH) and His-ventricle (HV) intervals and blood pressure (BP) before and after ranitidine were analyzed.

RESULTS

In Group 1, changes in SCL, SNRT, CSNRT, SACT, AH, HV and BP were not found to be significant. However, in Group 2, wherein the patients received ranitidine after autonomic blockade, it was observed that ranitidine significantly prolonged SCL (905.0 +/- 31.0 to 1000.0 +/- 40.0 msec, p = 0.001), decreased systolic BP (134.7 +/- 4.7 to 124.8 +/- 4.8 mmHg, p < 0.001), and diastolic BP (71.9 +/- 2.0 to 67.9 +/- 1.9 mmHg, p = 0.001), while the changes in SNRT, CSNRT, SACT, AH and HV were not significant.

CONCLUSIONS

A clinical dose of 150 mg ranitidine must be administered by a slow intravenous infusion for at least 5 minutes in case of patients suffering from sinus node dysfunction. Continuous monitoring of BP and heart rate are necessary, especially in cases of autonomic denervation.

[Effects of dynorphin A1-17 on the activities, immunoreactivities and mRNA expression of cNOS and iNOS in rat spinal cord and their mechanisms]

Intrathecal administration(i.t.) of Dynorphin A1-17(Dyn) 1.25-20 nmol produced dose-dependent paralysis of hindlimbs and tail as well as inhibition of tail flick and foot flinch reflexes. The Dyn spinal neurotoxicity and antinociception involve two differential mechanisms: Enhancement of NMDA-Ca(2+)-NOS/NO pathway and c-fos over-expression in the ventral spinal cord for neurotoxicity, and depression of NMDA receptor and NOS activities in the dorsal spinal cord for antinociception. Both brain-derived constitutive NOS (predominant at early stage) and inducible NOS (at later stage) are detrimental, but endothelial constitutive NOS might be beneficial to Dyn spinal neurotoxicity. Dyn exerts a dualistic modulatory effect on [Ca2+]i of the cultured rat single spinal neurons, inducing sustained overload of intracellular free calcium via both NMDA and kappa receptor activation at higher concentrations, and producing significant inhibition of the depolarization-evoked calcium influx only via kappa receptor activation at lower concentrations. Dyn exposure for 1 h produced direct neurotoxicity in the cultured spinal neurons within an optimal range of concentrations.

The effect of thrombolytic therapy on short- and long-term cardiac autonomic activity in patients with acute myocardial infarction

BACKGROUND

Reduced heart rate variability after acute myocardial infarction is an important risk stratification factor for mortality and life threatening ventricular arrhythmias. In recent years, thrombolytic therapy has revolutionized the therapy of acute myocardial infarction. However, there is little information about the mechanism of the beneficial effect of thrombolysis on cardiovascular mortality. This study was launched to investigate the relationship between thrombolytic therapy and cardiac autonomic activity, and the sequential changes in heart rate variability after acute myocardial infarction.

METHODS

From October 1994 to July 1995, all consecutive patients with their first acute myocardial infarction were prospectively enrolled into the study. Patients without contraindication underwent thrombolytic therapy within six hours of the onset of symptoms. Other patients received conventional treatment. Ambulatory electrocardiography (EKG) was recorded on each patient 7, 90 and 180 days after acute myocardial infarction. Heart rate variability in time- and frequency-domain was analyzed.

RESULTS

A total of 49 patients, 45 males and 4 females, were included in this study. The short-term heart rate variability (HRV) (seven-day) in the thrombolytic group was significantly higher than in the nonthrombolytic group in SDANN and SDNN. No significant difference in rMSSD, pNN50, LF, HF or LF/HF ratio was found. The location of MI did not influence the short-term HRV following acute myocardial infarction. In patients treated with thrombolytic agent, the follow-up HRV at 90 days and 180 days increased significantly compared to the baseline HRV (seven-day) in SDANN, SDNN, LF and HF bands. For patients without thrombolytic therapy, their follow-up HRV at 90-day and 180-day increased significantly as compared to the baseline HRV (seven-day) in SDANN and SDNN only. After correction of ventricular ejection fraction, the higher short-term (seven day) HRV activities were still present in SDANN and SDNN in patients with thrombolysis as compared to those without. The 90-day and 180-day HRV did not differ between patients with and without thrombolytic agent. Three patients died suddenly during follow-up, and all showed significantly lower values of HRV than the survivors.

CONCLUSIONS

The findings of the present study suggest that 1) in patients with uncomplicated AMI, HRV was transiently reduced with progressive improvement within three months after AMI in both those with and without thrombolytic therapy, and 2) patients who had received thrombolytic treatment had more improved HRV early (seven days) after AMI than those who did not. This improvement, independent of the change of left ventricular function, could be associated with the beneficial effect of thrombolytic therapy in patients with AMI.

[Effects of NA and 5-HT on the spontaneous and evoked activities of Purkinje cells in cerebellar slice]

Effects of NA and 5-HT perfusion on the spontaneous activity and evoked responses of the Purkinje cells (PCs) to stimulation of white matter were studied in the rat cerebellar slices. The results were as follows: (1) Perfusion with NA could elicit inhibitory, excitatory or biphasic responses of the spontaneously discharging PCs, with inhibitory response in dominance (79.8%). 5-HT perfusion could also exert either excitatory or inhibitory effect on PC spontaneous activity. (2) When NA and 5-HT were perfused successively, NA tended to inhibit while 5-HT tended to excite in 53.8% of the tested cells. (3) Most of the complex spike (CS) and simple spike (SS) responses evoked by white matter stimulation could be potentiated by NA (68.2%, 57.1%) or depressed by 5-HT (60.0%, 68.2%). (4) On the same cell under successively perfusion with NA and 5-HT, the evoked CS and SS responses of most cells (60.0%, 52.9%) showed a tendency to be facilitated by NA and suppressed by 5-HT. These results suggest that aminergic afferent fibers, by releasing NA and 5-HT, may affect PC's excitability and responsiveness to synaptic inputs from mossy and climbing fibers, thus playing an important role in the cerebellar function.

Visceral perception in functional gastro-intestinal disorders: disease marker or epiphenomenon?

The pathophysiology of functional gastro-intestinal disorders remains unclear. A relatively new approach to these disorders has been the study of visceral sensory perception. A decreased pain threshold to intraluminal balloon distension has been demonstrated in patients with irritable bowel syndrome, functional dyspepsia, and non-cardiac chest pain. This altered visceral sensitivity does not appear to extend to somatic sensation; patients have generally had normal sensory thresholds to various stimuli applied to the skin. It is uncertain whether altered gut sensation represents a primary event in the pathogenesis of disease or simply a disease marker. In this review, we examine the evidence of altered visceral sensation and discuss the implications for patient management and drug therapy.

Abnormal gastro-oesophageal reflux in Chinese with atypical chest pain

Although atypical chest pain has been well described in the Western population, its frequency in Chinese is unknown. Over a period of 42 months, we studied 521 Chinese patients with chest pain and identified 108 patients (20.7%) whose pain was not related to cardiac causes, as determined by exercise ECG or cardiac catheterization. Using 24 h ambulatory pH monitoring and baseline oesophageal manometry, 28.7, 19.4 and 5.6% of these patients were found to have abnormal reflux parameters, abnormal manometric findings or both, respectively. There were significantly more patients complaining of chest pain during the study in the gastro-oesophageal reflux disease (GERD) group than in the non-GERD group (16/31 vs 20/77; P < 0.001). The lower oesophageal sphincter pressure was lower in those with abnormal reflex parameters than in those with normal reflux parameters (12.7 +/- 5.4 vs 17.8 +/- 5.8 mmHg; P < 0.05). There was no significant difference in symptoms, such as heartburn (54.8 vs 42.9%), regurgitation (38.7 vs 35.1%) and dysphagia (19.4 vs 24.7%), among the two groups. Non-specific changes were the most frequent baseline motility pattern. In conclusion, atypical chest pain and gastro-oesophageal reflux disease are not uncommon in Chinese and this deserves special emphasis as the continuation of anti-anginal drugs may aggravate their condition.

Evidence of genetic heterogeneity of hypertrophic cardiomyopathy in eight Chinese patients

BACKGROUND

The genetic basis causing hypertrophic cardiomyopathy (HCM) was found due to missense mutations in cardiac beta-myosin heavy chain (beta-MHC), cardiac troponin T and alpha-tropomyosin genes in certain affected families. However, most mutations and majority of the affected families were reported to be related to beta-MHC gene. Till now, 20 different missense mutations of beta-MHC gene identified in more than 40 independent families were distributed in exons 8, 9, 13, 14, 15, 16, 19, 20, 21 and 23. Therefore, we chose these 10 exons for screening.

METHODS

Eight probands with HCM and 1 normal control were included for screening. 32P-labeled PCR products of these 10 exons of beta-MHC gene were amplified from genomic DNA obtained from peripheral lymphocytes. PCR-DNA single strand conformation polymorphism (PCR-SSCP) analysis was performed using electrophoresis with polyacrylamide gels with and without 10% glycerol. Large amount copies of these 10 exons were also made from genomic DNA with PCR. Detection of sequencing variation of these exons was determined by the direct sequencing method with dideoxy chain termination method and 35S.

RESULTS

No abnormal extra bands were noted on PCR-SSCP analysis. Sequencing analysis showed no missense mutation in these probands.

CONCLUSIONS

Genetic heterogeneity of HCM is evident in Chinese patients with HCM.

Dynorphin neurotoxicity induced nitric oxide synthase expression in ventral horn cells of rat spinal cord

Nitric oxide (NO) mediation in the spinal cord injury induced by intrathecal (i.t.) dynorphin (Dyn) administration was studied with NADPH-diaphorase (Nd) histochemistry. Normally, there was rarely NO synthase (NOS) activity in spinal cord motomeurons, and Dyn A(1-17) 10 nmol, which produced only transient paralysis, did not induce Nd/NOS expression in ventral horn cells. After a paralyzing dose of i.t. Dyn A(1-17) 20 nmol, which definitely produced permanent paraplegia and neuronal death, Nd/NOS began to express in motoneurons at 30 min, increased in numbers and intensities at 2-4 h and persisted up to 8 h. Most of Nd/NOS motoneurons disappeared at 24 h coincident with the neuronal death. Quite a few intensively-stained Nd-positive small cells and swollen varicosities became visible only in rats with permanent paraplegia and neuronal death, beginning at 2 h, maximizing at 3-4 h and remaining up to 24 h. These results suggest that NOS expression was induced in the ventral horn of spinal cord, including small cells and varicosities as well as motoneurons closely correlated in time and degree with pathological changes in motoneurons caused by spinal Dyn neurotoxicity.

Plasma haloperidol and reduced haloperidol concentrations in a geriatric population

Haloperidol (HL) and reduced haloperidol (RH) plasma concentrations were measured in geriatric patients (n = 45) and schizophrenic patients (n = 8). In the elderly patients, HL doses were 1-4 mg/day while only 2 mg/day was used in the schizophrenics. At HL 2 mg/day dose in both age groups, mean plasma HL levels were approximately twice as high in the elderly patients compared to the schizophrenics (1.39 +/- 0.82 vs. 0.56 +/- 0.23 ng/ml, p < 0.02). RH plasma concentrations were almost 5 times greater in the elderly patients (0.54 +/- 0.35 vs. 0.09 +/- 0.05 ng/ml, p < 0.0001). These results suggest that HL plasma concentrations in the elderly are greater than in adult schizophrenic patients treated with similar HL doses.

Haloperidol plasma concentrations in Taiwanese psychiatric patients

Haloperidol and reduced haloperidol are interconverted. The plasma concentrations of these two butyrophenones have been suggested to be important factors in determining the clinical effect of haloperidol treatment. The steady-state plasma concentrations of haloperidol and reduced haloperidol were measured in 322 Taiwanese schizophrenic patients using high performance liquid chromatography. The daily doses of haloperidol varied from 5 to 200 mg (mean +/- SD, 35.3 +/- 34.6 mg). There was a positive correlation between plasma concentrations and doses, following the equation: haloperidol concentration (ng/mL) = 0.88 x dose (mg/day)-1.66. However, the interpatient variation in haloperidol concentrations was up to ten-fold even in patients receiving the same dose (20 mg/day, n = 88). The expected values were about 10% to 50% higher than those reported in Caucasian patients. The plasma reduced haloperidol concentrations were significantly lower than, and correlated with, those of haloperidol in patients with haloperidol levels lower than 25 ng/mL. However, once haloperidol exceeded 25 ng/mL, reduced haloperidol levels rapidly elevated and appeared significantly higher than haloperidol levels. While haloperidol could reach its steady state in about 1 week, reduced haloperidol needed at least 4 weeks to do so. Haloperidol doses of less than 30 mg/day and plasma concentrations lower than 25 ng/mL are recommended for most Chinese patients.

Measurements of heart rate variability in patients with unexplained syncope

BACKGROUND

Syncope is a common clinical issue with complex and heterogenous etiologies. Research has shown a large proportion of syncope remained unexplained, even after serial investigations. Head-up tilt test with or without isoproterenol infusion could elicit a recurrence in most patients with unexplained syncope. Therefore, autonomically neural-mediated bradycardia and hypotension have been cited as the mainstays of the mechanism. Since the autonomic function can be reflected by heart rate rariability, this study proposed to determine 24-hour heart rate variability in patients with unexplained syncope.

METHODS

Fifteen patients, 14 males and 1 female, who were defined as showing symptoms of unexplained syncope, were the subjects of this study. Their ages ranged from 38 years to 79 years. Seventeen healthy volunteers matching in age and sex served as the control group. For each patient and volunteer, 24-hour ambulatory electrocardiographic monitoring was done. Heart rate variability was defined as SDNN index, SDNN, SDANN, rMSSD, and pNN50 in time domain measures; and low, high, and total frequency in frequency domain measures.

RESULTS

There was a significantly lower value at low frequency, high frequency, total frequency, rMSSD, and pNN50 in the syncope group than in the control group (p < 0.05). There was no significant difference in SDNN, SDNN index, SDANN and LF/HF ratio between these two groups.

CONCLUSIONS

Patients with unexplained syncope had autonomic withdrawal; this was the case either in both sympathetic and parasympathetic components without changing the sympatho-vagal balance, or in purely parasympathetic component.

Does coronary artery disease with stressed myocardial ischemia alter heart rate variability?

BACKGROUND

Research has shown that decreased heart rate variability (HRV) is independently associated with increased mortality after acute myocardial infarction. However, the relationship between HRV and myocardial ischemia still remains controversial. The purposes of this study were (1) to determine the relationship between HRV and atherosclerosis of the coronary artery; and (2) to determine the relationship between HRV and the extent of coronary stenosis in patients with stressed myocardial ischemia.

METHODS

Forty-six patients, 41 males and 5 females, were included in this study. Ages ranged from 50 years to 79 years. Seventeen volunteers served as the control group, which was comprised of 15 males and 2 females of ages ranging from 40 years to 74 years. For each patient a left ventriculogram and a coronary angiogram were performed. According to their coronary angiograms, patients were divided into normal coronary artery group, atherosclerotic coronary artery group and significant coronary artery disease group. An ambulatory EKG was performed on each patient and volunteer. Heart rate variability was defined as SDNN, SDANN, rMSSD, and pNN50 in time domain measures; and low and high frequency in frequency domain measures.

RESULTS

There were no significant differences in all variables of heart rate variability between the atherosclerotic coronary artery group and normal coronary artery group. In addition, there were no significant differences in all variables between the significant coronary artery disease group and the control group or between the significant coronary artery disease group and the normal coronary artery group.

CONCLUSIONS

These studies have shown that atherosclerotic or significant coronary artery disease with stressed myocardial ischemia does not impair 24-hour heart rate variability.

Plasma homovanillic acid and treatment response in a large group of schizophrenic patients

Plasma levels of homovanillic acid (pHVA), a metabolite of dopamine, were measured in ninety-five Chinese schizophrenic patients free of neuroleptics for at least four weeks. These patients were treated with classical antipsychotics for six weeks. Pretreatment pHVA was positively correlated with the subsequent clinical response (r = 0.408, p < 0.0001). Good responders (BPRS improvement > or = 50%, n = 47) had higher pretreatment pHVA levels than poor responders (BPRS improvement < 50%, n = 48) (15.7 +/- 8.4 ng/ml versus 9.9 +/- 3.7 ng/ml, p < 0.0001). A higher than 15 ng/ml pretreatment pHVA level was associated with a more consistent clinical response to the subsequent treatment. Using a pHVA level of 12 ng/ml as a demarcation point, 72% of patients (34 of 47) who had pHVA > or = 12 responded whereas 65% (31 of 48) who had < 12 did not respond (chi-square = 13.02, p < 0.0001). These results suggest that higher pretreatment pHVA levels may predict a better clinical response to antipsychotics. Based upon the pHVA findings, two hypothetical subtypes of schizophrenia are proposed.

Prolonged haloperidol and reduced haloperidol plasma concentrations after decanoate withdrawal

Haloperidol and reduced haloperidol plasma concentrations were measured in twelve schizophrenic patients upon cessation of haloperidol decanoate (HLD) treatment. Each patient received HLD 100 mg every 4 weeks for five injections. After the fifth injection, HLD was discontinued. Haloperidol and reduced haloperidol plasma concentrations were obtained prior to cessation and at weeks 1, 3, 4, 5, 7, 9, 11, and 13 post-injection. Haloperidol and reduced haloperidol plasma concentrations were assayed by HPLC. Both haloperidol and reduced haloperidol plasma concentrations were detectable 13 weeks post HLD discontinuation. Maximal haloperidol plasma concentrations were observed at one week post cessation and gradually declined. The mean elimination half-life for haloperidol was 27.4 +/- 8.6 days (range 19.0-47.0 days). Reduced haloperidol plasma concentrations declined very slowly. Our results show that both haloperidol and reduced haloperidol plasma concentrations can remain for extended time periods after HLD is discontinued.

Reduced haloperidol/haloperidol ratios after oral haloperidol and decanoate administration in schizophrenics

1. Haloperidol and reduced haloperidol plasma concentrations were measured in thirteen stable schizophrenic patients that received both oral haloperidol and haloperidol decanoate. 2. Significant correlations between reduced haloperidol/haloperidol ratios from oral haloperidol and haloperidol decanoate occurred at week two and week 16, respectively. 3. The formation of RH was consistent during haloperidol decanoate treatment.

Pericardiocentesis: a 20 patients study

Emergency pericardiocentesis, guided by a two-dimensional echocardiography, was performed on twenty patients with symptomatic pericardial effusion of various types and causes. There were fourteen men and six women. The underlying causes were: primary lung cancer (6 cases), metastatic cardiac tumors (3 cases), tuberculosis (4 cases), complicated interventional procedures with cardiac chamber or vessel perforations (2 cases), dissecting aortic aneurysm (1 case), systemic lupus erythematous (1 case), idiopathic pericarditis (1 case), bacterial pericarditis (1 case), and myxedema heart disease (1 case). Seventeen cases were performed through the left xipho-sternal approach and 3 cases through the apical approach. None of the patients died as a result of these procedures. A two-dimensional echocardiogram is useful in diagnosing cardiac tamponade as well as in guiding pericardiocentesis, and obtaines highly positive results (20/20). The positive rate of pericardial fluid cytology for malignant cells was 89% (8/9), however, pericardial fluid cultures or direct smear for tuberculosis were negative (0/4). In cancer patients, the mean survival time following pericardiocentesis was 4.2 months (range, 1-7.8 months). We concluded that neoplastic involvement of the pericardium is the most frequent cause of symptomatic pericardial effusion. Pericardiocentesis assisted by a two-dimensional echocardiogram is safe and easy. In addition, pericarditis caused by TB is still significant and must be considered in every case in our nation.

A clinical study of schizophrenic suicides. 42 cases in Taiwan

A clinical study of 25 male and 17 female schizophrenic suicides is presented. Jumping from a height was the most common method used. The 42 suicidal schizophrenics in Taiwan were compared with both 84 sex- and age-matched and 60 5-year illness course non-suicidal schizophrenic control groups. The suicidal schizophrenics were not significantly different from the non-suicidal counterparts of both control groups with regard to age, sex, ethnicity, religion, educational background, the presence of suicide cases in the family history, and the presence of insight, but were significantly different in characteristics of a history of previous suicide attempts, presence of psychotic symptoms during their final month, depression during their final month, a history of depression, a history of previous psychiatric hospitalizations, and the number of hospitalizations. We discuss the findings from this study and others in the literature in the context of the different clinical and socio-cultural backgrounds of these Taiwanese schizophrenic suicides.

Aortic and pulmonary input impedance in patients with cor pulmonale

The hydraulic load of the right and left ventricles and the clinical effects of nifedipine were evaluated in 8 normal subjects (mean age: 55 years) and 8 patients with cor pulmonale secondary to chronic obstructive lung disease (mean age: 57 years). It was found that there were differences in the right ventricular resistance (174.62 +/- 25.96 vs 468.57 +/- 178.81 dyne/sec/cm-5), first zero crossing frequency (3.62 +/- 0.34 vs 6.07 +/- 3.56 Hz), steady power (218.95 +/- 32.25 vs 359.44 +/- 37.46 mW) and total power of right ventricle (275.81 +/- 36.18 vs 440.46 +/- 85.16 mW) between the normal and cor pulmonale patients, respectively. However, no significant changes in characteristic impedance, pulsatile power or aortic impedance were observed in the right pulmonary artery. After administration of nifedipine to patients with cor pulmonale, there were significant changes in resistance (468.57 +/- 178.81 vs 256.36 +/- 178.56 dyne/sec/cm-5), steady power (359.44 +/- 37.46 vs 225.51 +/- 114.64) and total power (440.46 +/- 85.16 vs. 289.27 +/- 50.85) of the pulmonary artery, respectively. Otherwise there were no significant changes in aortic input impedance or characteristic impedance of right pulmonary artery and pulsatile power. In conclusion, we found that: 1) the hydraulic vascular load in the right ventricle was higher in patients with cor pulmonale, 2) characteristic impedance that was not increased in cor pulmonale patients may be due to a dilated pulmonary artery, 3) there was no impedance mismatch between left ventricle and systemic arterial system in patients with cor pulmonale, and 4) by reducing the pulmonary vascular resistance through nifedipine administration, the total external right ventricular power might be reduced, without affecting the proximal pulmonary arterial compliance.