Human granulocytic anaplasmosis with rash and rhabdomyolysis: A case report

Human granulocytic anaplasmosis (HGA) is a tick-borne infection caused by Anaplasma phagocytophilum. Only seven cases of HGA have been reported in Japan to date. We report the case of a 61-year-old female farmer who developed HGA with rash and rhabdomyolysis. The patient had fever and erythema covering the entire body, including the palms. An induration with an eschar was observed on the right leg, indicating that the patient had been bitten by a tick. Elevated serum creatinine and creatinine kinase levels and hematuria indicated rhabdomyolysis. We suspected Japanese spotted fever, a tick-borne illness caused by Rickettsia Japonica, and administered minocycline and ciprofloxacin for a week. Transient neutropenia and thrombocytopenia were observed, but the symptoms improved. Polymerase chain reaction (PCR) and antibody tests for R. japonica and Orientia tsutsugamushi, which causes scrub typhus, were both negative. The PCR test for severe fever with thrombocytopenia syndrome virus was also negative. Antibodies against A. phagocytophilum-related proteins were detected by western blotting, indicating seroconversion of IgG with paired serum samples, and the patient was diagnosed with HGA. HGA should be suspected in acute febrile patients with a history of outdoor activity and cytopenia, with or without a rash. A testing system and the accumulation of cases in Japan are necessary for the early diagnosis and appropriate treatment of HGA.

Luteibacter jiangsuensis blood stream infection: a first case report

BACKGROUND

Luteibacter jiangsuensis is a gram-negative aerobic bacillus that was first isolated from soil samples at a pesticide factory in China and reported in 2011. Here, we describe the first case of L. jiangsuensis infection in human.

CASE PRESENTATION

A 59-year-old Japanese woman undergoing treatment for Crohn's disease was admitted to our hospital with fever. Clinical examination indicated catheter-related bloodstream infection. The catheter was removed and meropenem was initiated. Morphologically identical glucose non-fermentative gram-negative bacilli were detected from two sets of aerobic blood culture and catheter-tip cultures. MALDI-TOF mass spectrometry failed to identify the bacterium, which was later identified as L. jiangsuensis by 16 S rRNA gene sequencing. Antimicrobial susceptibility test revealed that the isolate was resistant to carbapenem, therefore meropenem was switched to intravenous levofloxacin (500 mg/day). After 14 days of treatment with levofloxacin, the patient was discharged.

CONCLUSIONS

This is the first case of L. jiangsuensis infection in human. The strain was identified by 16 S rRNA gene sequence analysis.

Safety and efficacy of 5-aminolevulinic acid phosphate/iron in mild-to-moderate coronavirus disease 2019: A randomized exploratory phase II trial

BACKGROUND

5-aminolevulinic acid (5-ALA), a natural amino acid that is marketed alongside sodium ferrous citrate (SFC) as a functional food, blocks severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proliferation in vitro and exerts anti-inflammatory effects. In this phase II open-label, prospective, parallel-group, randomized trial, we aimed to evaluate the safety and efficacy of 5-ALA in patients with mild-to-moderate coronavirus disease 2019.

METHODS

This trial was conducted in patients receiving 5-ALA/SFC (250/145 mg) orally thrice daily for 7 days, followed by 5-ALA/SFC (150/87 mg) orally thrice daily for 7 days. The primary endpoints were changes in SARS-CoV-2 viral load, clinical symptom scores, and 5-ALA/SFC safety (adverse events [AE] and changes in laboratory values and vital signs).

RESULTS

A total of 50 patients were enrolled from 8 institutions in Japan. The change in SARS-CoV-2 viral load from baseline was not significantly different between the 5-ALA/SFC (n = 24) and control (n = 26) groups. The duration to improvement was shorter in the 5-ALA/SFC group than in the control group, although the difference was not significant. The 5-ALA/SFC group exhibited faster improvement rates in "taste abnormality," "cough," "lethargy," and "no appetite" than the control group. Eight AEs were observed in the 5-ALA/SFC group, with 22.7% of patients experiencing gastrointestinal symptoms (decreased appetite, constipation, and vomiting). AEs occurred with 750/435 mg/day in 25.0% of patients in the first phase and with 450/261 mg/day of 5-ALA/SFC in 6.3% of patients in the second phase.

CONCLUSION

5-ALA/SFC improved some symptoms but did not influence the SARS-CoV-2 viral load or clinical symptom scores over 14 days. The safety of 5-ALA/SFC in this study was acceptable. Further evaluation using a larger sample size or modified method is warranted.

A Multicenter Randomized Controlled Trial To Evaluate the Efficacy and Safety of Nelfinavir in Patients with Mild COVID-19

Nelfinavir, an orally administered inhibitor of human immunodeficiency virus protease, inhibits the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro. We conducted a randomized controlled trial to evaluate the clinical efficacy and safety of nelfinavir in patients with SARS-CoV-2 infection. We included unvaccinated asymptomatic or mildly symptomatic adult patients who tested positive for SARS-CoV-2 infection within 3 days before enrollment. The patients were randomly assigned (1:1) to receive oral nelfinavir (750 mg; thrice daily for 14 days) combined with standard-of-care or standard-of-care alone. The primary endpoint was the time to viral clearance, confirmed using quantitative reverse-transcription PCR by assessors blinded to the assigned treatment. A total of 123 patients (63 in the nelfinavir group and 60 in the control group) were included. The median time to viral clearance was 8.0 (95% confidence interval [CI], 7.0 to 12.0) days in the nelfinavir group and 8.0 (95% CI, 7.0 to 10.0) days in the control group, with no significant difference between the treatment groups (hazard ratio, 0.815; 95% CI, 0.563 to 1.182; P = 0.1870). Adverse events were reported in 47 (74.6%) and 20 (33.3%) patients in the nelfinavir and control groups, respectively. The most common adverse event in the nelfinavir group was diarrhea (49.2%). Nelfinavir did not reduce the time to viral clearance in this setting. Our findings indicate that nelfinavir should not be recommended in asymptomatic or mildly symptomatic patients infected with SARS-CoV-2. The study is registered with the Japan Registry of Clinical Trials (jRCT2071200023). IMPORTANCE The anti-HIV drug nelfinavir suppresses the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro. However, its efficacy in patients with COVID-19 has not been studied. We conducted a multicenter, randomized controlled trial to evaluate the efficacy and safety of orally administered nelfinavir in patients with asymptomatic or mildly symptomatic COVID-19. Compared to standard-of-care alone, nelfinavir (750 mg, thrice daily) did not reduce the time to viral clearance, viral load, or the time to resolution of symptoms. More patients had adverse events in the nelfinavir group than in the control group (74.6% [47/63 patients] versus 33.3% [20/60 patients]). Our clinical study provides evidence that nelfinavir, despite its antiviral effects on SARS-CoV-2 in vitro, should not be recommended for the treatment of patients with COVID-19 having no or mild symptoms.

Evaluation of a Novel FKS1 R1354H Mutation Associated with Caspofungin Resistance in Candida auris Using the CRISPR-Cas9 System

Outbreaks of invasive infections, with high mortality rates, caused by multidrug-resistant Candida auris have been reported worldwide. Although hotspot mutations in FKS1 are an established cause of echinocandin resistance, the actual contribution of these mutations to echinocandin resistance remains unknown. Here, we sequenced the FKS1 gene of a caspofungin-resistant clinical isolate (clade I) and identified a novel resistance mutation (G4061A inducing R1354H). We applied the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system to generate a recovered strain (H1354R) in which only this single nucleotide mutation was reverted to its wild-type sequence. We also generated mutant strains with only the R1354H mutation introduced into C. auris wild-type strains (clade I and II) and analyzed their antifungal susceptibility. Compared to their parental strains, the R1354H mutants exhibited a 4- to 16-fold increase in caspofungin minimum inhibitory concentration (MIC) while the H1354R reverted strain exhibited a 4-fold decrease in caspofungin MIC. In a mouse model of disseminated candidiasis, the in vivo therapeutic effect of caspofungin was more closely related to the FKS1 R1354H mutation and the virulence of the strain than its in vitro MIC. The CRISPR-Cas9 system could thus aid in elucidating the mechanism underlying drug resistance in C. auris.

Echinocandin Resistance in Candida auris Occurs in the Murine Gastrointestinal Tract Due to FKS1 Mutations

Candida auris is resistant to multiple antifungal agents. This study investigated its antifungal susceptibility and explored FKS1 mutations across the isolates from mice enterically colonized with wild-type C. auris and treated with echinocandin. Resistant C. auris with FKS1 mutations, including S639F, S639Y, D642Y, R1354H, or R1354Y, were isolated and found to be micafungin- and caspofungin-resistant in vivo; however, the MICs of isolates with mutation in R1354 remained below the micafungin breakpoint in vitro.

Clinical Differentiation of Severe Fever with Thrombocytopenia Syndrome from Japanese Spotted Fever

Severe fever with thrombocytopenia syndrome (SFTS) and Japanese spotted fever (JSF; a spotted fever group rickettsiosis) are tick-borne zoonoses that are becoming a significant public health threat in Japan and East Asia. Strategies for treatment and infection control differ between the two; therefore, initial differential diagnosis is important. We aimed to compare the clinical characteristics of SFTS and JSF based on symptomology, physical examination, laboratory data, and radiography findings at admission. This retrospective study included patients with SFTS and JSF treated at five hospitals in Nagasaki Prefecture, western Japan, between 2013 and 2020. Data from 23 patients with SFTS and 38 patients with JSF were examined for differentiating factors and were divided by 7:3 into a training cohort and a validation cohort. Decision tree analysis revealed leukopenia (white blood cell [WBC] < 4000/μL) and altered mental status as the best differentiating factors (AUC 1.000) with 100% sensitivity and 100% specificity. Using only physical examination factors, absence of skin rash and altered mental status resulted in the best differentiating factors with AUC 0.871, 71.4% sensitivity, and 90.0% specificity. When treating patients with suspected tick-borne infection, WBC < 4000/µL, absence of skin rash, and altered mental status are very useful to differentiate SFTS from JSF.

Associations between Chest CT Abnormalities and Clinical Features in Patients with the Severe Fever with Thrombocytopenia Syndrome

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by the SFTS virus. It involves multiple organ systems, including the lungs. However, the significance of the lung involvement in SFTS remains unclear. In the present study, we aimed to investigate the relationship between the clinical findings and abnormalities noted in the chest computed tomography (CT) of patients with SFTS. The medical records of 22 confirmed SFTS patients hospitalized in five hospitals in Nagasaki, Japan, between April 2013 and September 2019, were reviewed retrospectively. Interstitial septal thickening and ground-glass opacity (GGO) were the most common findings in 15 (68.1%) and 12 (54.5%) patients, respectively, and lung GGOs were associated with fatalities. The SFTS patients with a GGO pattern were elderly, had a disturbance of the conscious and tachycardia, and had higher c-reactive protein levels at admission (p = 0.009, 0.006, 0.002, and 0.038, respectively). These results suggested that the GGO pattern in patients with SFTS displayed disseminated inflammation in multiple organs and that cardiac stress was linked to higher mortality. Chest CT evaluations may be useful for hospitalized patients with SFTS to predict their severity and as early triage for the need of intensive care.

Determination of physiological cardiac myosin-binging protein levels (cMyc) in healthy populations

Background

Cardiac myosin–binding protein C (cMyC) is a cardiac-restricted protein that has more abundant, rapid release and clearance kinetics than cardiac troponin. The current ESC guideline suggests the cMyC may provide value as an alternative to cardiac troponin. The 99th percentile value is universally endorsed as the reference cut off to aid in the diagnosis of acute myocardial infarction (AMI), however, none of the report of healthy population of cMyC.

Purpose

The aim of this study was to evaluate the distribution of cMyC values in healthy subjects.

Methods

We used two cohorts in this retrospective study. 1) Healthy subjects; a total of 500 subjects (250 men and 250 women) who had annual health examinations in 2012 in the area of Kamigoto, a suburb of Nagasaki city in Southern Japan were enrolled. All participants showed none of abnormal findings including cell blood counts, chemical analysis, liver function tests, general urine tests, occult blood tests of stool, barium swallow, mammography for women, abdominal ultrasound sonography, and electrocardiogram. All blood samples were obtained in a fasting state in the morning. 2) Chest pain subjects; we collected samples from 250 subjects including 50 with non-ST elevation myocardial infarction visited admitted to a university hospital for measurement of high-sensitivity troponin T and coronary artery assessment by coronary angiography. We measured cMyC level in both cohorts by HISCL™-800 system (Sysmex corporation, Japan). The assay has a limit of detection of 0.5 ng/L and a lower limit of quantification of 1.3 ng/L.

Result

In healthy subjects, median age (IQR) was 44 (20, 82) in men and 50 (23, 91) in women. The 99th percentile of cMyC was 27.3 ng/L, which was around one-third lower than that in previous report (87 ng/L). In chest pain subjects, the concentrations of cMyC at presentation were significantly higher in those with versus without AMI (median, 66 ng/L versus 10 ng/L, P&lt;0.001). Discriminatory power for AMI, as quantified by the area under the receiver-operating characteristic curve (AUC), was comparable for cMyC (AUC, 0.85 (95% CI 0.79–0.91) and hs-cTnT (AUC, 0.81 (95% CI 0.76–0.88)).

Conclusion

We defined the normal range of cMyC in healthy Japanese subjects. The level of cMyC at presentation provides discriminatory power comparable to hs-cTnT in the diagnosis of AMI. To determine the physiological value of a biomarker may be necessary to evaluate enough information about their health status.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research

One-year outcome of the rule-out group according to the 0-h /1-hour algorithm with suspected myocardial infarction in Asian countries

 

Background/Introduction; A rapid rule-out or rule-in protocol based on the 0-h/1-hour algorithm using high-sensitivity cardiac troponin T (hs-cTnT) is recommended by the European Society of Cardiology (ESC). Around 40–50% were stratified into “rule-out” group, and their 30-days prognosis was excellent. However, the one-year prognosis is uncertain. We aimed to better characterize these patients.

Methods

This study was a prospective, multi-center, observational study of patients with suspected non-ST elevation acute coronary syndrome (NSTE-ACS) admitted to 5 hospitals in Japan and Taiwan from 2014 November to 2018 December, respectively.

All patients underwent a clinical assessment the included medical history, physical examination, 12-lead ECG, standard blood test, chest radiography. Exclusion criteria were ST elevated myocardial infarction, chronic kidney disease (serum creatinine more than 3 mg/dL) and congestive heart failure, arrhythmia, or infection disease. The patients were divided into three groups according to the algorithm; “rule-out”, “observe” and “rule-in”. The final diagnosis was then adjudicated by 2 independent cardiologists using all available information, including coronary angiography, coronary computed tomography, stress electrocardiography and follow-up data. The presence of acute myocardial infarction (AMI) was defined according to the Fourth Universal Definition of Myocardial Infarction. After hospital discharge patients were follow after one-year b telephone or in written form. Major adverse cardiovascular events (including death myocardial infarction, coronary artery bypass grafting, percutaneous coronary intervention (PCI)) were recorded by establishing contact with the patient and the family physicians. The primary prognosis end point was all-cause mortality.

Results

Of the 1,187 patients were analyzed after exclusion. The prevalence rate of AMI was 16.1%. According to the algorithm, 42% (n=493) of patients were assigned to “rule-out” group and had no AMI nor death. The most common final adjudicated diagnoses were atypical chest pain (80%), gallstone attack (3%) and vasospastic angina pectoris (2%). All patients with unstable angina (4.7%) underwent PCI.

Conclusion(s)

Our findings suggest that the “rule-out” group patients according to ESC 0-h/1-hour algorithm provides very high safety and efficacy for the triage toward AMI.

Funding Acknowledgement

Type of funding source: None

Novel and potent antimicrobial effects of caspofungin on drug-resistant Candida and bacteria

Echinocandins, including caspofungin, micafungin, and anidulafungin, are first-line antifungal agents for the treatment of invasive candidiasis. They exhibit fungicidal activity by inhibiting the synthesis of β-1,3-D-glucan, an essential component of the fungal cell wall. However, they are active only against proliferating fungal cells and unable to completely eradicate fungal cells even after a 24 h drug exposure in standard time-kill assays. Surprisingly, we found that caspofungin, when dissolved in low ionic solutions, had rapid and potent antimicrobial activities against multidrug-resistant (MDR) Candida and bacteria cells even in non-growth conditions. This effect was not observed in 0.9% NaCl or other ion-containing solutions and was not exerted by other echinocandins. Furthermore, caspofungin dissolved in low ionic solutions drastically reduced mature biofilm cells of MDR Candida auris in only 5 min, as well as Candida-bacterial polymicrobial biofilms in a catheter-lock therapy model. Caspofungin displayed ion concentration-dependent conformational changes and intracellular accumulation with increased reactive oxygen species production, indicating a novel mechanism of action in low ionic conditions. Importantly, caspofungin dissolved in 5% glucose water did not exhibit increased toxicity to human cells. This study facilitates the development of new therapeutic strategies in the management of catheter-related biofilm infections.

P2677A combination of HEART score and a 0-hour/1-hour algorithm for early and safe triage tool for patients in observe zone

Background

The European Society Cardiology guidelines recommend that a 0-hour/1-hour (0–1hr) algorithm using high sensitivity cardiac troponin T (hs-cTnT) improves the early triage of patients with suspected non-ST elevation acute coronary syndrome (NSTE-ACS). However, diagnostic uncertainty remains in the 25–30% of patients assigned to “observe” group.

Purpose

To establish a step wise risk score system using HEART score and 0-hour/1-hour algorithm to identify the low risk group from observation group.

Methods

This study was a prospective, multi-center, observational study of patients with suspected NSTE-ACS admitted to five hospitals in Japan and Taiwan from 2014 to 2018, respectively. We applied the algorithm and calculated HEART score simultaneously. Patients were divided into three groups according to the algorithm: hs-cTnT below 12 ng/L and delta 1 hour below 3 ng/L were the “rule out” group; hs-cTnT at least 52 ng/L or delta 1 hour at least 5 ng/L were in the “rule in” group; the remaining patients were classified as the “observe” group. All patients underwent a clinical assessment the included medical history, physical examination, 12-lead ECG, continuous ECG monitoring, pulse oximetry, standard blood test, chest radiography, cardiac and abdominal ultrasonography. Patients presenting with congestive heart failure, terminal kidney disease on hemodialysis state, arrhythmia, or infection disease (which causes to increase troponin level) were excluded. Thirty-day MACE was defined as acute myocardial infarction, unstable angina (UA), or death.

Results

Of the 1,332 patients enrolled, 933 patients were analyzed after exclusion. NSTE-ACS was the final diagnosis for 122 (13.1%) patients and none of death. The HEART score less than 4 points in observation groups identified as very low risk with a negative predictive value (NPV) of 98.1% (95% confidential interval (CI); 90.1%-100%) and sensitivity of 98.0% (95% CI; 89.6%-100%). There were only one patient (0.5%) with AMI. In case of the HEART score less than 5 points, it could also identify as very low risk with a NPV of 96.7% (95% CI; 90.8%-99.3%%) and sensitivity of 94.1% (95% CI; 83.8%-98.8%). There were only three patients (1.2%) with AMI.

Conclusion

A combination of HEART score and the 0-hour/1-hour algorithm strategy rapidly identified the patient in observation group of 30-day MACE including UA where nor further cardiac testing would be needed.

Acknowledgement/Funding

JSPS KAKENHI Grant Number JP18K09554

P2676Prospective validation of the 2015 ESC 0-hour/1-hour algorithm using high-sensitivity cardiac troponin T in Asian countries

Background/Introduction

Implementation of the 2015 ESC 0-hour/1-hour algorithm using high-sensitivity troponin (hs-cTn) T in Asian countries presents a challenge for clinical practice.

Purpose

We aimed to prospectively validate the 0-hour/1-hour algorithm in Asian countries.

Methods

We conducted a prospective, multi-center, international cohort already utilizing 0-hour/1-hour algorithm using hs-cTnT for evaluation of patients with suspected of non-ST elevation acute coronary syndrome (NSTE-ACS). All patients underwent a clinical assessment the included medical history, physical examination, 12-lead ECG, continuous ECG monitoring, pulse oximetry, standard blood test, chest radiography, cardiac and abdominal ultrasonography. Patients presenting with congestive heart failure, terminal kidney disease on hemodialysis state, arrhythmia, or infection disease (which cause to increase troponin level) were excluded. Patients were divided into three groups according to the algorithm: hs-cTnT below 12 ng/L and delta 1 hour below 3 ng/L were the “rule out” group; hs-cTnT at least 52 ng/L or delta 1 hour at least 5 ng/L were in the “rule in” group; the remaining patients were classified as the “observational” group. The final diagnosis was then adjudicated by 2 independent cardiologists using all available information, including coronary angiography, coronary computed tomography, stress electrocardiography and follow-up data. The presence of acute myocardial infarction (AMI) was defined according to the Fourth Universal Definition of Myocardial Infarction.

Results

Of the 1,332 patients enrolled in 2014 to 2018, 933 patients were analyzed after exclusion. AMI was the final diagnosis for 122 (13.1%) patients. The algorithm ruled out AMI in 401 patients with a negative predictive value and sensitivity of 100% (95% confidential interval [CI], 98.6%-100%) and 100% (95% CI, 94.0%-100%), respectively, in the rule-out group. None of the patients were diagnosed with AMI. Among the 211 patients classified into the rule-in group, 90 were diagnosed as having AMI. The positive predictive value and specificity were 43.1% (95% CI, 36.2%-50.2%) and 78.3% (95% CI, 74.5%-81.7%), respectively. The median length of hospital stay was 159 min (142–180) in rule out group.

Conclusion(s)

Our findings suggest that the 0-hour/1-hour algorithm using hs-cTnT provides very high safety and efficacy for the triage toward rapid rule-out to rule-in of AMI.

Acknowledgement/Funding

JSPS KAKENHI Grant Number JP18K09554

Nivolumab infusion reaction manifesting as plantar erythema and pulmonary infiltrate in a lung cancer patient

Infusion reaction is an adverse event of therapeutic monoclonal antibodies. Nivolumab, an anti-programmed death-1 antibody, directly activates T cells, which could probably interact with endothelial cells. The etiology of infusion reaction induced by nivolumab may differ from that of other antibodies; however, the detailed clinical features are unknown. We report a case of lung cancer treated with nivolumab, in which the infusion reaction manifested as plantar erythema, followed by a transient local pulmonary infiltrate around the tumor. Physicians should be aware that an infusion reaction induced by anti-programmed death-1 antibodies could appear as local cutaneous and pulmonary adverse events.

Alert Regarding Cisplatin-induced Severe Adverse Events in Cancer Patients with Xeroderma Pigmentosum

Xeroderma pigmentosum (XP) is a genetic disease in which DNA repair mechanisms are impaired. Cisplatin (CDDP) exerts cytotoxic effects by forming mainly intrastrand DNA cross-links, and sensitivity to CDDP depends on the DNA repair system. Several in vitro studies have suggested that treatment with CDDP may cause enhanced adverse events as well as anti-tumor activity in cancer patients with XP. This article is the first to describe two cancer patients with XP showing severe adverse events following CDDP-based chemotherapy. Physicians should pay attention when administering CDDP in cancer patients with XP.

Pulmonary Artery Sarcoma Overexpressing Platelet-derived Growth Factor Receptor α

Pulmonary artery sarcoma is highly malignant and easily metastasizes to the systemic organs. Both the introduction of novel diagnostic procedures and the development of new treatment modalities are required to achieve long-term survival. Several studies have shown that platelet-derived growth factor receptor α (PDGFRα) gene amplification is frequently observed in pulmonary artery sarcoma. PDGFRα is known to be involved in cell proliferation in certain malignancies. PDGFRα may become a potential biological marker in pulmonary artery sarcoma. We report a case in which a diagnosis of pulmonary artery sarcoma overexpressing PDGFRα was made using endovascular catheter biopsy following positron emission tomography with integrated computed tomography (PET/CT) scans.

Evidence of frequent introductions of Japanese encephalitis virus from south-east Asia and continental east Asia to Japan

The Japanese encephalitis virus (JEV) circulating in Japan consists of viruses with multiple phylogenetic origins. Phylogenetic analysis revealed that some JEV strains have recently migrated from south-east and continental east Asian countries. One phylogenetic subcluster of the JEV strains circulating in Japan was closely related to viruses isolated in Vietnam and China's inland region while other JEV subclusters were related to viruses isolated in Shanghai, China. One virus subcluster, however, was isolated solely in Japan and was not found in any other Asian country. Therefore, our data suggests that the JEVs that have remained or are circulating in Japan include a mixture of viruses that have previously migrated from south-east and continental east Asian countries.

Relationship between toxicity and cadmium accumulation in rats given low amounts of cadmium chloride or cadmium-polluted rice for 22 months

To clarify toxic effects of long-term oral administration of low dose cadmium (Cd) on the liver and kidney, six groups of female Sprague-Dawley rats were fed a diet containing Cd-polluted rice or CdCl2 at concentrations up to 40 ppm, and killed after 12, 18, and 22 months. With toxicological parameters, including histopathology, there was no evidence of Cd-related hepato-renal toxicity, despite a slight decrease of mean corpuscular volume and mean corpuscular hemoglobin of red blood cells with 40 ppm CdCl2. Dose-dependent accumulation of Cd was observed in the liver and kidneys with peak levels of 130 +/- 42 micrograms/g and 120 +/- 20 micrograms/g, respectively, at 18 months in animals treated with 40 ppm CdCl2. A dose-dependent increase in urinary Cd levels became evident with time. Induction of metallothionein (MT) was also observed in the liver and kidney with a high correlation to the corresponding Cd levels. In the proximal renal tubular epithelia of 40 ppm CdCl2-treated rats at 22 months, prominent accumulation of Cd was observed in secondary lysosomes associated with MT deposits in their exocytotic residual bodies. The results demonstrated that, in contrast to the case with high-dose Cd-administration, renal toxicity is not induced by long-term oral administration of low amounts of Cd, although tissue accumulation does occur. Possible protective mechanisms may be operating.

Origin of Ca2+ necessary for carbachol-induced contraction in longitudinal muscle of the proximal colon of rats

The origin of Ca2+ necessary for carbachol (CCh)-induced contraction of longitudinal muscle of the proximal colon of rats was studied. CCh induced contraction of the muscle consisting of two phases, phasic and tonic phases, with a concomitant biphasic increase in [Ca2+]i. After removal of Ca2+ from the bathing solution of the colonic segments, CCh-induced contraction was rapidly inhibited; there was almost complete inhibition 1 min after the removal. Nicardipine, a blocker of voltage-dependent calcium channel, also significantly inhibited CCh-induced contraction. On the other hand, treatment of the colonic segments with thapsigargin, an inhibitor of sarcoplasmic reticulum (SR) Ca2+-ATPase, did not significantly affect the contraction except causing a slight decrease in the rate of contraction. These results suggest that Ca> entering through voltage-dependent calcium channels, but not released from SR, is essential for CCh-induced contraction of longitudinal muscle of the proximal colon of rats. This strict dependency of the CCh-induced contraction on extracellular Ca2+ was discussed in relation to the results obtained in the fundus of rats.

ST segment elevation in the right precordial leads following administration of class Ic antiarrhythmic drugs

Electrocardiographic changes were evaluated retrospectively in five patients without previous episodes of syncope or ventricular fibrillation who developed abnormal ST segment elevation mimicking the Brugada syndrome in leads V1-V3 after the administration of class Ic antiarrhythmic drugs. Pilsicainide (four patients) or flecainide (one patient) were administered orally for the treatment of symptomatic paroxysmal atrial fibrillation or premature atrial contractions. The QRS duration, QTc, and JT intervals on 12 lead surface ECG before administration of these drugs were all within normal range. After administration of the drugs, coved-type ST segment elevation in the right precordial leads was observed with mild QRS prolongation, but there were no apparent changes in JT intervals. No serious arrhythmias were observed during the follow up periods. Since ST segment elevation with mild QRS prolongation was observed with both pilsicainide and flecainide, strong sodium channel blocking effects in the depolarisation may have been the main factors responsible for the ECG changes. As the relation between ST segment elevation and the incidence of serious arrhythmias has not yet been sufficiently clarified, electrocardiographic changes should be closely monitored whenever class Ic drugs are given.

Assessment of renal toxicity by analysis of regeneration of tubular epithelium in rats given low-dose cadmium chloride or cadmium-polluted rice for 22 months

To determine whether low-dose oral administration of cadmium (Cd) induces renal toxicity, six groups of female Sprague-Dawley rats were fed a diet containing low amounts of CdCl2 or Cd-polluted rice at concentrations up to 40 ppm, and were killed after 12, 18, and 22 months (experiment 1). In addition to the determination of cortical Cd levels and histopathological assessment of kidneys, labeling indices (LIs) for proliferating cell nuclear antigen (PCNA) in the renal cortical tubular epithelium of Cd-treated rats were determined as a measure of regenerative activity. For comparison, the kidneys of rats given diets containing small to large amounts of CdCl2 up to 600 ppm for 4 months were similarly examined (experiment 2). Animals in experiment 1 demonstrated spontaneous chronic nephropathy and fluctuation in the tubular PCNA LI, but these findings were not correlated with renal Cd levels at 22 months. PCNA LI on the other hand, appeared to be linked to the severity of chronic nephropathy. In experiment 2, levels of CdCl2 of 200 ppm or more clearly induced degeneration and apoptosis of proximal tubules with high correlations between renal Cd levels, PCNA LI, and the severity of tubular degeneration. The results demonstrated that, in contrast to high-dose Cd administration, treatment with 40 ppm or less for 22 months did not influence tubular regeneration as a component of nonspecific chronic nephropathy, suggesting that long-term oral administration of low levels of Cd does not injure renal tubules in female rats.

Does an early increase in heart rate during tilting predict the results of passive tilt testing?

Head-up tilt testing is a useful but time-consuming procedure. If we could accurately predict the tilt testing results; we would be able to substantially shorten the duration of tilt protocol. To clarify the hypothesis that an early increase in heart rate (HR) during tilting can predict the passive tilt results in our protocol (80-degree angle for 30 minutes), we studied 115 consecutive patients (72 men, 43 women, mean age 46 +/- 19 years) who were clinically diagnosed with neurally mediated syncope. Twenty-nine (25%) patients had a positive tilt test (P group), whereas 86 (75%) patients had a negative test (N group). The early HR increase was defined as the maximum HR during the first 5 minutes of tilting minus the resting HR before tilting. The early HR increase was significantly higher in the P group (23.8 +/- 9.5 beats/min) than in the N group (17.5 +/- 8.2 beats/min, P = 0.0008), but it was negatively correlated with the tilt duration to positive response (r = -0.52, P = 0.0032) and the patient age in the entire study population (r = 0.62, P < 0.0001). Results of multiple regression analysis indicated that age, tilt result, and tilt duration were independently associated with the early HR increase. As a result, an early HR increase > or = 18 beats/min, the best apparent cut-off point obtained in our study, was a sensitive (100%) marker for prediction of a positive response at < or = 15 minutes of tilting, but it showed a low specificity (61%). In conclusion, an early HR increase during 80-degree tilting may be only predictive for a positive result < or = 15 minutes because it depends on the tilt duration to a positive response and patient age.

Circadian variation of vasovagal syncope

INTRODUCTION

Circadian patterns have been demonstrated for several cardiovascular catastrophes. Chronobiologic factors play a role in the emergence of vasovagal syncope (VVS); however, diurnal variation of syncopal episodes in VVS has not been reported previously.

METHODS AND RESULTS

We assessed daily distribution of the time of syncopal episodes in VVS. Time of syncope could be determined in 80 episodes in 54 patients (32 men and 22 women; mean age 37 years, range 12 to 67). Patients who were prescribed beta blockers or vasodilators, and who had syncopes related to alcohol intake, were excluded from the study. Head-up tilt testing was performed in 53 patients. The distribution of the episodes of VVS in 3-hour intervals differed significantly from uniform occurrence (P < 0.0001), with a peak frequency between 6 A.M. and noon (67.5% of total episodes). In patients who had experienced the initial syncope in the morning, most (78%) of the next syncopal episodes also occurred in the morning. There was no significant correlation between the time of last syncopes and tilt testing results.

CONCLUSION

We demonstrated a prominent circadian variation in the frequency of VVS, with a peak in the morning. Recognition of the daily distribution of VVS is useful for patient education and therapeutic strategy.

Inhibitory effects of chondroitin sulfate prepared from salmon nasal cartilage on fat storage in mice fed a high-fat diet

OBJECTIVE

Chondroitin sulfate is an acidic polymer consisting of repeating D-glucuronic acid and D-N-acetylgalactosamine units, and the N-acetylgalactosamine is substituted with the sulfate at either the 4' or 6' position, with approximately one sulfate being present per disaccharide unit. The present study assessed the effects of chondroitin sulfate on the activity of pancreatic lipase and lipid uptake into brush border membrane vesicles of the rat small intestine in vitro, and on the degree of fat storage induced in mice by the oral administration of a high-fat diet for 8 weeks.

DESIGN AND MEASUREMENTS

Experiments were carried out to clarify whether or not chondroitin sulfate inhibited pancreatic lipase activity in assay systems using triolein emulsified with phosphatidylcholine or gum arabic. In addition, the effects of chondroitin sulfate on lipid absorption by brush border membrane vesicles were examined. Moreover, mice were fed a high-fat diet and treated with chondroitin sulfate for 8 weeks.

RESULTS

Chondroitin sulfate dose-dependently inhibited the pancreatic lipase activity in an assay system using triolein emulsified with phosphatidylcholine. In addition, chondroitin sulfate inhibited the palmitic acid uptake into the brush border membrane vesicles of the rat jejunum. Chondroitin sulfate caused the reduction of body weight and parametrial adipose tissue weight, and prevention of fatty liver and hyperlipidemia in mice fed a high-fat diet.

CONCLUSION

The reduction of fat storage and the antihyperlipidemic action of chondroitin sulfate might be due to the inhibition of small intestinal absorption of dietary fat through the inhibition of pancreatic lipase activity and fatty acid uptake through brush border membrane.

Torsion of the fallopian tube following sterilization

A 45-year-old woman presented severe right lower abdominal pain. Transabdominal sonography demonstrated bilateral adnexal cystic masses. At surgery, these cystic masses were bilateral simple hydrosalpinges with torsion of the right side. She had previously had tubal ligation. When we encounter an adnexal torsion, we should consider tubal torsion when there is a history of tubal ligation.

[Methodology of 80 degrees head-up tilt testing with and without low dose isoproterenol provocation in Japanese patients with neurally mediated syncope]

The usefulness of 80 degrees head-up tilt testing with and without low dose isoproterenol provocation was evaluated for the diagnosis of neurally mediated syncope (NMS) in Japanese. Head-up tilt testing was performed in 114 consecutive patients with clinical diagnoses of NMS (68 men, 46 women, mean age 46 +/- 21 years), and 57 times in 36 healthy volunteers (26 men, 10 women, mean age 31 +/- 8 years) who had no history of syncope or presyncope. Head-up tilt testing used an 80 degrees angle for 30 minutes (passive tilt), and if the passive tilt resulted in negative response, isoproterenol was infused at 0.01-0.02 microgram/kg/min and the tilt repeated for 10 minutes (isoproterenol tilt). A positive response was defined as the development of syncope or a presyncopal state associated with hypotension, bradycardia or cardiac arrest. The sensitivities of passive tilt testing for a positive response after 5-, 10-, 15-, 20-, 25- and 30-minute tilting were 1%, 9%, 14%, 19%, 24%, and 28%, respectively, and specificities after 5-, 10-, 15-, 20-, 25- and 30-minute tilting were 100%, 95%, 91%, 88%, 86%, and 84%, respectively. The sensitivities of isoproterenol tilt testing with 0.01 and 0.02 microgram/kg/min were increased to 37% and 48%, respectively. This improvement was statistically significant between the passive tilt and isoproterenol tilt testing with a dose of 0.02 microgram/kg/min (p < 0.01). However, specificities were comparable with those of the passive tilt testing (84% and 82%, respectively). In conclusion, 80 degrees passive tilt testing for 30 minutes showed a low sensitivity (28%) but acceptable specificity (84%). Low-dose isoproterenol provocation was useful for improving sensitivity (48%) while maintaining a comparable specificity (82%).

Arrhythmogenic right ventricular cardiomyopathy with an initial manifestation of severe left ventricular impairment and normal contraction of the right ventricle

A case of arrhythmogenic right ventricular cardiomyopathy (ARVC) with an initial manifestation of severe impairment of the left ventricle (LV) and normal contraction of the right ventricle (RV) is presented. A 43-year-old man was admitted to hospital because of congestive heart failure following a common cold. The LV function was diffusely and severely hypokinetic. Coronary arteriogram revealed normal vessels. An endomyocardial biopsy specimen obtained from the RV septum revealed mild infiltration of lymphocytes with focal myocytes necrosis and so healing myocarditis was suspected. The specimen did not include any fatty replacement of myocytes. Since then, the patient suffered from recurrent congestive heart failure as well as nonsustained ventricular tachycardia and required frequent hospitalization. Progressive impairment, dilation, and thinning of both ventricles were observed on serial echocardiographic examinations. Although the RV gradually enlarged and became impaired, severe dilatation and impairment of the LV has always been predominant in the patient's clinical course. After medical follow-up for 10 years, he died suddenly of ventricular fibrillation and pump failure. The autopsy revealed extensive fibrofatty replacement of myocytes in both the ventricles, extending from the outer layer to the inner layer of myocardium in the RV and to the middle layer in the LV. These features were compatible with arrhythmogenic right ventricular cardiomyopathy or perimyocarditis, although only the rightsided bundle of the interventricular septum was completely replaced by fatty tissue, which can not be explained as a sequel of perimyocarditis. Moreover, apoptosis was present in the myocyte nuclei of the myocardial layers bordering the area of fatty replacement. Therefore, myocarditis may have triggered or accelerated the process of apoptosis leading to ARVC.

Fatty acid alcohol ester-synthesizing activity of lipoprotein lipase

The fatty acid alcohol ester-synthesizing activity of lipoprotein lipase (LPL) was characterized using bovine milk LPL. Synthesizing activities were determined in an aqueous medium using oleic acid or trioleylglycerol as the acyl donor and equimolar amounts of long-chain alcohols as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with LPL, palmityl oleate was synthesized, in a time- and dose-dependent manner. Apo-very low density lipoprotein (apoVLDL) stimulated LPL-catalyzed palmityl oleate synthesis. The apparent equilibrium ratio of fatty acid alcohol ester/oleic acid was estimated using a high concentration of LPL and a long (20 h) incubation period. The equilibrium ratio was affected by the incubation pH and the alcohol chain length. When the incubation pH was below pH 7.0 and long chain fatty acyl alcohols were used as substrates, the fatty acid alcohol ester/free fatty acid equilibrium ratio favored ester formation, with an apparent equilibrium ratio of fatty acid alcohol ester/fatty acid of about 0.9/0.1. The equilibrium ratio decreased sharply at alkaline pH (above pH 8.0). The ratio also decreased when fatty alcohols with acyl chains shorter than dodecanol were used. When a trioleoylglycerol/fatty acyl alcohol emulsion was incubated with LPL, fatty acid alcohol esters were synthesized in a dose- and time-dependent fashion. Fatty acid alcohol esters were easily synthesized from trioleoylglycerol when fatty alcohols with acyl chains longer than dodecanol were used, but synthesis was decreased with fatty alcohols with acyl chain lengths shorter than decanol, and little synthesizing activity was detected with shorter-chain fatty alcohols such as butanol or ethanol.

Wax ester-synthesizing activity of lipases

The synthesis/hydrolysis of wax esters was studied in an aqueous solution using purified rat pancreatic lipase, porcine pancreatic carboxylester lipase, and Pseudomonas fluorescens lipase. The equilibrium between wax ester synthesis and hydrolysis favored ester formation at neutral pH. The synthesizing activities were measured using free fatty acid or triacylglycerol as the acyl donor and an equimolar amount of long-chain alcohol as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with these lipases, wax ester was synthesized, in a dose- and time-dependent manner, and the apparent equilibrium ratio of palmityl oleate/free oleic acid was about 0.9/0.1. These lipases catalyzed the hydrolysis of palmityl oleate emulsified with gum arabic, and the apparent equilibrium ratio of palmityl oleate/free oleic acid was also about 0.9/0.1. The apparent equilibrium ratio of wax ester/free fatty acid catalyzed by lipase depended on incubation pH and fatty alcohol chain length. When equimolar amounts of trioleoylglycerol and fatty acyl alcohol were incubated with pancreatic lipase, carboxylester lipase, or P. fluorescens lipase, wax esters were synthesized dose-dependently. These results suggest that lipases can catalyze the synthesis of wax esters from free fatty acids or through degradation of triacylglycerol in an aqueous medium.

Tissue distribution of cadmium in rats given minimum amounts of cadmium-polluted rice or cadmium chloride for 8 months

To investigate the relationship between cadmium (Cd) toxicity, intestinal absorption, and its distribution to various tissues in rats treated orally with minimum amounts of Cd, 14 female rats per dose group per time point were given diets consisting of 28% purified diet and 72% ordinary rice containing Cd-polluted rice (0. 02, 0.04, 0.12, or 1.01 ppm of Cd) or CdCl(2) (5.08, 19.8, or 40.0 ppm of Cd) for up to 8 months. At 1, 4, and 8 months after the commencement of Cd treatment, seven rats per group were euthanized for pathological examinations to determine the Cd concentrations in the liver and kidneys and metallothionein (MT) in the liver, kidneys, intestinal mucosa, serum, and urine. One week before each period of 1, 4, and 8 months, the remaining seven rats in each group were administered a single dosage of (109)Cd, a tracer, to match the amounts of the designated Cd doses (about 1.2 to 2400 microg/kg body wt). They were euthanized 5 days later to determine the distribution of Cd to various tissues. No Cd-related toxic changes were observed. The concentrations of Cd in the liver and kidneys at any time point and MT in the liver, kidney, serum, and urine at 4 and 8 months increased dose-dependently, whereas MT in the intestinal mucosa did not alter markedly at any time point. The distribution rates of Cd to the liver increased dose-dependently (40% at lower doses to 60% at higher doses), whereas those to the kidney decreased dose-dependently (20% at lower doses to 10% at higher doses). The Cd retention rates 5 days after (109)Cd administration (amounts of Cd in various tissues/amounts of Cd administered) ranged from 0.2 to 1. 0% at any time point. These results suggest that the distribution of Cd to the liver and kidneys after the oral administration vary depending on the dosage levels of Cd. The difference of the distribution pattern of Cd to the liver and kidney is probably due to the difference in the form of the absorbed Cd, i.e., free ion or Cd-MT complex, although not closely related to the MT in the intestinal mucosa.

Acute performance of steroid-eluting screw-in leads for atrial free wall pacing

The aim of this study was to clarify the acute performance of steroid-eluting screw-in leads in comparison with that of nonsteroid screw-in leads for atrial free wall pacing. In 114 cases (68 males, 46 females, average age 70 years) with atrial free wall pacing by screw-in leads, pacing thresholds and P-wave amplitudes were compared at the time of implantation and 1 week later between 68 cases of nonsteroid and 46 cases of steroid-eluting screw-in leads. No significant differences were seen between the 2 groups at implantation in either voltage or current thresholds measured at pulse widths of 0.1, 0.3, 0.6, 1.0, 2.0 ms, or P-wave amplitudes. Pulse width thresholds at outputs of 2.5 V and 5.0 V were significantly lower for steroid leads 1 week after implantation (2.5 V: 0.34+/-0.27 ms nonsteroid vs. 0.12+/-0.08 ms steroid, p<0.001; 5.0 V: 0.12+/-0.08 ms nonsteroid vs. 0.06+/-0.02 ms steroid, p<0.01). P-wave amplitudes after 1 week were significantly higher for steroid leads (2.6+/-0.7 mV nonsteroid vs 3.0+/-1.2 mV steroid, p<0.001). Threshold rise, including pacing failure, was observed in 15 (22%) of the non-steroid leads, but in only 1 (2%) of the steroid leads. In conclusion, steroid-eluting screw-in leads suppress the acute rise of pacing thresholds in the right atrial free wall and their acute performance is better than that of non-steroid leads. These results suggest that appropriate low-output atrial pacing is feasible immediately after implantation.

Analysis of heart rate variability during head-up tilt testing in a patient with idiopathic postural orthostatic tachycardia syndrome (POTS)

A 16-year-old boy was diagnosed with idiopathic postural orthostatic tachycardia syndrome (POTS) during head-up tilt testing. During a passive tilt, the patient's heart rate (HR) increased by 30 beats/min within 5 min. After 25 min of tilting, his HR further increased to 133 beats/min and he began to complain of lightheadedness and weakness without hypotension. Power spectral analysis of HR variability during the tilt test revealed that the ratio of low and high frequency powers increased with the onset of orthostatic intolerance. Propranolol (10mg every morning) dramatically alleviated his clinical symptoms, and he has been asymptomatic with gaining weight after discontinuing his crowded train commuting.

Relationship between hormone-sensitive lipolysis and lipase activity in rat fat cells

An assay for total hormone-sensitive lipase (HSL) in rat fat cells was devised in which fat-associated HSL was solubilized with ether, and triolein or cholesteryloleate was used as substrate. Norepinephrine (NE) caused marked release of glycerol from fat cells but did not activate HSL as estimated using triolein or cholesteryloleate as substrate. Propranolol, a beta-blocker, inhibited NE-induced lipolysis in fat cells without a concomitant reduction in HSL activity. The antilipolytic action of insulin on NE-induced lipolysis could not be explained by a decrease in HSL activity. Neither ACTH-induced lipolysis in fat cells nor its inhibition by insulin was accompanied by matching fluctuations in HSL activity. These results indicate that neither NE and ACTH-induced lipolysis in fat cells, nor the antilipolytic actions of propranolol and insulin, involve fluctuations in HSL activity.

Runaway pacemaker caused by a stuck accelerometer

We report a case of runaway pacemaker with a ventricular pacing rate of 190 beats/min. The runaway occurred when the accelerometer became stuck due to the magnet application during VVIR pacing. Runaways in modern pacemakers are particularly rare, but they do still occur. The best solution for this phenomenon is generator replacement.

Poor reproducibility of false-positive tilt testing results in healthy volunteers

Positive responses to head-up tilt testing occur in healthy subjects. However, the reproducibility of "false-positive" tilt testing results has not been clarified. To study the reproducibility of "false-positive" responses, we prospectively performed 2 tilt tests separated by 1 to 10 (mean 3.2) weeks in 20 healthy males aged 23 to 40 years (mean 30 years). The baseline tilt test (80 degrees for 30 minutes) ended positive in 4 (20%) subjects on the initial test and 2 (10%) on the second test with only 1 (5%) who had consecutive positive responses. No additional positive responses were noted during the isoproterenol (0.01 microgram/kg/min)-tilt test for 10 minutes. We demonstrated that a false-positive response occurred in 5 (25%) of 20 young males who underwent 2 tilt tests, however, only 1 (5%) subject had consecutive positive responses. Poor reproducibility may be characteristic of false-positive responses in head-up tilt testing.

Response to head-up tilt testing in patients with situational syncope

The results of head-up tilt testing were compared between 24 patients with situational syncope and 44 age-matched patients with typical vasovagal syncope. Patients with situational syncope showed poor positive responses, especially in the passive tilt results (8.3% vs. 39%, p = 0.0078).

Alkaline lipase from brain: is it the same enzyme as pancreatic lipase from pancreas?

A new alkaline lipase was detected in rat brain and its properties were compared with those of the well-characterized pancreatic lipase and pancreatic lipase-related protein 2. The activity of the alkaline lipase was determined using trioleoylglycerol emulsion at pH 8.0. Subcellular fractions were prepared from brain homogenates by differential centrifugation. Lipase activities of the cytosolic fraction (the supernatant obtained by differential centrifugation of 100,000g) were stimulated by addition of colipase and bile salts and inhibited by addition of an antibody against rat pancreatic lipase. The partially purified enzyme had an isoelectric point of pH 6.8, which was identical to that found for rat pancreatic lipase. The enzyme had interfacial activation and dependence on colipase in the presence of bile salts. The enzyme had no measurable phospholipase A activity. The band produced by the enzyme on SDS-polyacrylamide gel electrophoresis was identical to that of the rat pancreatic lipase when detected by immunoblotting analysis using an antibody against pancreatic lipase. These results show that pancreatic lipase such as alkaline lipase is in rat brain.

Transient left bundle branch block induced by left-sided cardiac catheterization in patients without pre-existing conduction abnormalities

A traumatic left bundle branch block (LBBB) is uncommon in a patient with intact atrioventricular conduction. Three of our patients developed LBBB during a left-sided catheterization. Two patients suffered from angina pectoris and the other had an abdominal aneurysm. Two of them had a history of hypertension. None of the patients had ever shown any conduction abnormalities before the catheterization. The electrocardiogram just before the examination was normal in all 3 patients. LBBB was observed when a catheter was introduced into the left ventricle, and lasted 2--4 min without significant change in heart rates. Examination revealed no significant stenosis proximal to the first septal perforator and normal left ventricular contraction in all patients. One patient developed permanent LBBB 14 months later. Catheter-induced LBBB may occur easily with certain anatomical characteristics of the left bundle branch or the distal His bundle, with or without some concealed damage to the conduction system. It is important to keep this complication in mind and to pay adequate attention to patients' electrocardiograms as well as their angiographical findings, especially in those with pre-existing right bundle branch block.

Safety and efficacy of oral flecainide acetate in patients with cardiac arrhythmias

We retrospectively studied the clinical efficacy and safety of oral flecainide in 38 patients with symptomatic arrhythmias. Patients received 100 to 200 mg daily of flecainide for a mean of 25 months (range 8 to 50 months). All patients had normal cardiac function. Paroxysmal atrial fibrillation (PAF) was observed in 29 patients (76%). Other forms of arrhythmia included paroxysmal atrial flutter, seen in 3 patients (8%); premature atrial contraction and ventricular premature contraction, each seen in 2 patients (5%); and supraventricular tachycardia and ventricular tachycardia, each seen in 1 patient (3%). A complete response was obtained in 15 (52%) of 29 patients with PAF and a partial response in 8 patients (27%). The remaining 6 patients (21%) showed no response. A complete response was also obtained in 7 of 9 patients with other forms of arrhythmia. There were no differences in cardiac function and ECG parameters before and after treatment. Flecainide was withdrawn in 4 patients due to the development of electrocardiographic abnormalities. Three of these patients showed an atrial proarrhythmic effect. Abnormal ST elevations in the precordial leads were observed in 1 patient who received 200 mg of flecainide daily. In conclusion, flecainide was effective treatment for supraventricular and ventricular arrhythmias, but attention must be paid to the drug's potential proarrhythmic adverse effects.

Paroxysmal atrioventricular block induced during head-up tilt testing in an apparently healthy man

INTRODUCTION

Prolonged asystole during head-up tilt testing has been reported, but the occurrence of paroxysmal AV block appears to be rare.

METHODS AND RESULTS

A 25-year-old man with no history of syncope underwent head-up tilt testing. After 11 minutes of 80 degrees tilting, he developed syncope with paroxysmal AV block and asystole lasting 10.5 seconds. However, this response was not reproduced during a subsequent tilt test 4 weeks later. Treadmill exercise testing and Holter monitoring showed no abnormalities. Power spectral analysis of heart rate variability revealed a marked increase in sympathetic activity several minutes before the induction of paroxysmal AV block.

CONCLUSION

We report a case of paroxysmal AV block that occurred during head-up tilt testing but did not recur on a subsequent test in an apparently healthy young man.