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PubMed2002

Risk factors for breakthrough candidemia.

In order to assess the risk factors for breakthrough candidemia (candidemia occurring in patients receiving at least 3 days of systemic fluconazole or amphotericin B), 270 cases of candidemia occurring in two tertiary hospitals were analyzed. Using multivariate analysis, profound neutropenia (<100/mm(3)) (odds ratio [OR], 9.14), use of corticosteroids (OR, 3.17), and heavy antibiotic exposure (previous use of 2 or more antibiotics for at least 14 days) (OR, 2.93) were identified as risk factors. Neither the susceptibility of the isolates nor the presence of a catheter was found to be a risk factor. These data suggest that gastrointestinal colonization plays a major role in the development of breakthrough candidemia.

Amphotericin B↗
PubMed2004

Effect of the addition of wine distillery wastes to vineyard soils on the adsorption and mobility of fungicides.

In the present work, a study was made of the effect of the addition of liquid and solid wine distillery wastes (WLW and WSW) to vineyard soils on the adsorption and leaching of penconazole and metalaxyl, two fungicides of different hydrophobic character that are widely used in vine cultivation. The study of these processes is of great interest, since currently the green filter system is implemented simultaneously in vine cultivation and as an alternative to classic purification methods of such organic wastes. Three vineyard soils selected from the La Rioja region (NW Spain) were used. Adsorption isotherms of the 14C-labeled fungicides by the soils in aqueous medium and in WLW medium were obtained, together with the percolation curves of the fungicides in packed soil columns under saturated flow conditions. The adsorption and leaching of metalaxyl in a soil amended with WSW were also studied. The Freundlich Kf constants indicated an increase in the adsorption of both fungicides by the soils in WLW medium as compared to aqueous medium. The amounts of penconazole leached in the three soils when they were washed with water and WLW ranged between 3.18 and 39.3% and between 2.00 and 10.4%, respectively, of the total fungicide added to the columns. In the case of metalaxyl, these amounts represented 69.1-100 and 91.6-117%. Variations were also observed in the shape and parameters of the breakthrough curves obtained in both systems and in the presence of WSW. The soluble organic compounds of WLW must be retained by the soil components, creating new adsorbent hydrophobic surfaces, which increase the retention in the soil of the highly hydrophobic compound penconazole. In the case of metalaxyl, which is very water soluble, the soluble organic compounds of WLW seem to contribute to the increase in its leaching, whereas the WSW favors the opposite effect. The results obtained, indicating modifications in the adsorption and leaching of penconazole and metalaxyl in the presence of WLW and WSW, show that further studies should be carried out on the adsorption and mobility of the fungicides in soils from the vineyard zone, which in turn are used as a green filter purification system of wine wastes.

Adsorption↗
PubMedDate not supplied

The efficacy of chemoprophylaxis against malaria with chloroquine plus proguanil, mefloquine, and atovaquone plus proguanil in travelers from Denmark.

BACKGROUND: The risk of malaria infection in travelers is seldom known in detail and neither is the efficacy of different prophylactic regimens, due to a lack of controlled trials. Surveillance of malaria diagnosed after return can provide data on risk and efficacy. METHODS: An open case-control study was initiated. Imported cases were notified to our department and were studied in 320 permanent residents in Denmark, returning from abroad with malaria from 1997 to 1999. These were compared with a group of 600 travelers who were not infected with malaria and matched by age, sex, and destination. Information on the use of chemoprophylaxis and the length of stay in malarious areas were obtained by questionnaire. RESULTS: Two hundred cases of Plasmodium falciparum malaria were notified of which 103 had used chloroquine and proguanil, 16 mefloquine, and 3 atovaquone and proguanil as prophylaxis, whereas the rest had taken other drugs or no prophylaxis. This study showed that the risk increased with increasing exposure and that compliance was lower especially for mefloquine users in malaria cases compared with controls. The study provided the first comprehensive data on the use of atovaquone/proguanil to travelers. The estimated efficacy of chloroquine and proguanil, mefloquine, and atovaquone and proguanil in fully compliant users was 1:599, 1:2,232, and 1:1,943, respectively, P. falciparum cases per prescription. The country specific risk data showed that the risk of getting malaria varied from 1 per 140 travelers to Ghana to almost 1 per 40,000 to Thailand, providing data that allow the use of prophylaxis to be restricted to high-risk areas. CONCLUSION: There was a considerable variation in risk between the countries with the highest risk in tropical Africa. Chloroquine and proguanil was less efficient compared with mefloquine. Atovaquone/proguanil (Malarone) was at least as efficient as mefloquine, but breakthroughs were observed.

Africa↗
PubMed1990

Advances in the management of victims struck by ruptured intracranial aneurysms.

The advances in management of victims struck by the rupture of an intracranial aneurysm is reviewed. In the 1970s the management outcome was still far from acceptable; many victims who had 'recovered' following a major aneurysmal subarachnoid haemorrhage (SAH) succumbed or became crippled as the result of repeat bleeds and/or delayed SAH-induced ischaemic deterioration ('cerebral vasospasm'). The era of prosperity for microneurosurgery, the introduction of the calcium channel blocker nimodipine and the accumulation of cases in centres with a team of dedicated aneurysm surgeons form the basis of a recent breakthrough in the previously gloomy management outcome. With microsurgical techniques elective surgery can now be performed in the acute stage thereby preventing disastrous reruptures which occur frequently in the early phase after the first bleed. The concomitant use of nimodipine minimizes delayed SAH-induced ischaemic deterioration. Today a management regime including early operation combined with nimodipine has led to grossly improved results. Nevertheless cognitive disturbances and psychosocial maladjustment are frequent sequelae following a major aneurysmal bleed. Hope for further improvements could depend on the development of techniques which may allow identification of intracranial aneurysms before they rupture and increased knowledge of the aetiology of such cerebral arterial wall lesions.

Aged↗
PubMed1991

Protective gloves of polymeric materials. Experimental permeation testing and clinical study of side effects.

In the occupational use and handling of hazardous chemicals and infectious materials, exposure must be minimized. To diminish the risk of direct skin contact and percutaneous toxicity, the use of protective gloves is one of the most important measures to consider. For effective protection, the selection process must include evaluation of permeation test data as well as the risk of side effects possibly caused by the glove materials. In permeation testing (in vitro), breakthrough time and permeation rate are key values measured. Test conditions such as size and design of the permeation test cell, flow rate of the collecting medium through the test cell, measurement systems, testing procedures and analytical equipment can vary and can have crucial influence on the test results. In the present investigation, five permeation test cells of different sizes and design were used, the collecting gas flow rate was varied between 60 and 120 ml/min and 120 to 500 ml/min, the ASTM F 739 and ISO/DIS standard test procedures were performed using two different measurement systems, and in vitro versus in vivo testing techniques were studied. Gloves and glove materials of neoprene were exposed to four organic solvents. The breakthrough times (in vitro) for the test chemicals were slightly influenced by variations in cell size and design, flow rate and test procedure. The only significant influence on the breakthrough time values was between the two measurement systems, direct flow and automatic sampling. On the other hand, the permeation rate values were affected to a much greater extent, in most cases significantly. The test conditions in the in vitro and in vivo procedures differed in many ways and the test results were therefore compared on a relative basis. The breakthrough time values for the solvents through gloves of vinyl, natural rubber and butyl rubber were in the same rank order in both in vitro and in vivo testing. There was no evident correlation between the relative permeation rate values (in vitro) and the relative absorption rate values (in vivo). Disposable gloves of latex or plastic materials are also commonly used in health care as protection against microorganisms. Therefore contact with disinfectants is frequent. The resistance of gloves made of natural rubber latex, vinyl (PVC) and polyethylene to permeation by ethanol, isopropanol, m-chlorocresol and glutaraldehyde-based disinfectant was studied mainly according to the ISO/DIS permeation test procedure. In addition, glove pieces exposed to isopropanol and ethanol were studied with the scanning electron microscope (SEM).(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed2006

Process development for the removal and recovery of hazardous dye erythrosine from wastewater by waste materials-Bottom Ash and De-Oiled Soya as adsorbents.

Erythrosine is a water-soluble xanthene class of dye. It is widely used as colorant in foods, textiles, drugs and cosmetics. It is highly toxic, causes various types of allergies, thyroid activities, carcinogenicity, DNA damage behaviour, neurotoxicity and xenoestrogen nature in the humans and animals. The photochemical and biochemical degradation of the erythrosine is not recommended due to formation of toxic by-products. The present paper is an attempt to remove erythrosine from wastewater using adsorption over Bottom Ash-a power plant waste and De-Oiled Soya-an agricultural waste. Under the batch studies, effect of concentration of dye, temperature, pH of the solution, dosage of adsorbents, sieve size of adsorbents, etc., have been studied for the uptake of the dye over both adsorbents. The adsorption process verifies Langmuir and Freundlich adsorption isotherms in both the cases and based on the data different thermodynamic parameters have been evaluated. Batch studies also include kinetic measurements, rate constant study, mass transfer behaviour and establishment of mechanistic pathway for both the cases. For the bulk removal of the dye column operations have been carried out and breakthrough capacities of the Bottom Ash and De-Oiled Soya columns have been calculated. Attempts have also been made for the recovery of the adsorbed dye from exhausted columns by eluting dilute NaOH and more than 90% of the dye was recovered.

Adsorption↗
PubMed2002

Transseptal activation during left atrial pacing in humans: electroanatomic mapping using a noncontact catheter and the intracardiac echocardiography.

BACKGROUND: A better understanding of transseptal activation may be important for the treatment of atrial fibrillation, but little is known about preferential routes of conduction from the left atrium (LA) to the right atrium (RA) in humans. METHODS AND RESULTS: Twelve patients were studied. A noncontact mapping system was used to map the RA during pacing from several sites of LA at different cycle lengths. The location of the Bachmann's bundle (BB), the fossa ovalis (FO) and the coronary sinus (CS) ostium were determined using intracardiac echocardiography. The BB was the earliest area of right atrial activation during pacing from the atrial appendage, roof and postero-superior wall in 94% of cases. The FO was the area of earliest activation during pacing from the septum and the right superior pulmonary veins (PV) in 95% of cases. The CS ostium (alone or associated with the FO) was the region of transseptal breakthrough in all patients during pacing from the right inferior PV, postero-inferior wall and distal CS. Various patterns of activation with 2 or 3 distinct areas of transseptal breakthrough were observed during pacing from the lateral wall and the left superior PV. The pacing cycle length did not influence the modality of transseptal activation. CONCLUSIONS: Different patterns of transseptal activation were found during pacing from LA. The preferential routes of conduction from the LA to the RA were related to the sites of stimulation and were not influenced by the pacing cycle length.

Adult↗
PubMed2006

Substrate in the interventricular septum for left ventricular and right ventricular outflow tract tachycardia: ablation from the right side of the septum.

Simultaneous epicardial and endocardial mapping demonstrated that in a substantial number of ventricular tachycardias (VTs) endocardial, intramural, and epicardial structures are involved in the substrate of the reentrant circuits. Both right and left ventricular breakthrough has also been described during VT originating in the interventricular septum. We report the case of a patient with a nonischemic left ventricular aneurysm presenting with a left ventricular outflow tract (LVOT) tachycardia and a right ventricular outflow tract (RVOT) tachycardia. Mapping from the anterior interventricular vein and the endocardium of the RVOT revealed mid-diastolic potentials at the epicardium of the LVOT and the endocardium of RVOT, where the criteria of central isthmus sites could be demonstrated. Ablation targeting an isolated late potential during sinus rhythm in RVOT eliminated both the LVOT tachycardia and the RVOT tachycardia. In this patient with a nonischemic left ventricular aneurysm, the substrate of a LVOT tachycardia and RVOT tachycardia is described, and successful catheter ablation of the right and left ventricular tachycardia from the septal wall of RVOT is reported.

Adult↗
PubMed2005

Herb-drug interactions: a literature review.

Herbs are often administered in combination with therapeutic drugs, raising the potential of herb-drug interactions. An extensive review of the literature identified reported herb-drug interactions with clinical significance, many of which are from case reports and limited clinical observations. Cases have been published reporting enhanced anticoagulation and bleeding when patients on long-term warfarin therapy also took Salvia miltiorrhiza (danshen). Allium sativum (garlic) decreased the area under the plasma concentration-time curve (AUC) and maximum plasma concentration of saquinavir, but not ritonavir and paracetamol (acetaminophen), in volunteers. A. sativum increased the clotting time and international normalised ratio of warfarin and caused hypoglycaemia when taken with chlorpropamide. Ginkgo biloba (ginkgo) caused bleeding when combined with warfarin or aspirin (acetylsalicylic acid), raised blood pressure when combined with a thiazide diuretic and even caused coma when combined with trazodone in patients. Panax ginseng (ginseng) reduced the blood concentrations of alcohol (ethanol) and warfarin, and induced mania when used concomitantly with phenelzine, but ginseng increased the efficacy of influenza vaccination. Scutellaria baicalensis (huangqin) ameliorated irinotecan-induced gastrointestinal toxicity in cancer patients.Piper methysticum (kava) increased the 'off' periods in patients with parkinsonism taking levodopa and induced a semicomatose state when given concomitantly with alprazolam. Kava enhanced the hypnotic effect of alcohol in mice, but this was not observed in humans. Silybum marianum (milk thistle) decreased the trough concentrations of indinavir in humans. Piperine from black (Piper nigrum Linn) and long (P. longum Linn) peppers increased the AUC of phenytoin, propranolol and theophylline in healthy volunteers and plasma concentrations of rifamipicin (rifampin) in patients with pulmonary tuberculosis. Eleutheroccus senticosus (Siberian ginseng) increased the serum concentration of digoxin, but did not alter the pharmacokinetics of dextromethorphan and alprazolam in humans. Hypericum perforatum (hypericum; St John's wort) decreased the blood concentrations of ciclosporin (cyclosporin), midazolam, tacrolimus, amitriptyline, digoxin, indinavir, warfarin, phenprocoumon and theophylline, but did not alter the pharmacokinetics of carbamazepine, pravastatin, mycophenolate mofetil and dextromethorphan. Cases have been reported where decreased ciclosporin concentrations led to organ rejection. Hypericum also caused breakthrough bleeding and unplanned pregnancies when used concomitantly with oral contraceptives. It also caused serotonin syndrome when used in combination with selective serotonin reuptake inhibitors (e.g. sertraline and paroxetine). In conclusion, interactions between herbal medicines and prescribed drugs can occur and may lead to serious clinical consequences. There are other theoretical interactions indicated by preclinical data. Both pharmacokinetic and/or pharmacodynamic mechanisms have been considered to play a role in these interactions, although the underlying mechanisms for the altered drug effects and/or concentrations by concomitant herbal medicines are yet to be determined. The clinical importance of herb-drug interactions depends on many factors associated with the particular herb, drug and patient. Herbs should be appropriately labeled to alert consumers to potential interactions when concomitantly used with drugs, and to recommend a consultation with their general practitioners and other medical carers.

Animals↗
PubMed1992

Cycle control with triphasic norgestimate and ethinyl estradiol, a new oral contraceptive agent.

Effective cycle control was demonstrated based on two multicenter, 2-year studies of the triphasic oral contraceptive (OC) agent containing the new progestin norgestimate. The estrogen in this OC is ethinyl estradiol. These open-label Phase III studies were conducted in the United States by 33 investigators at 33 sites who treated a total of 1,783 subjects, healthy women 17 to 38 years of age with menstrual cycle characteristics considered to be within the normal range. The norgestimate/ethinyl estradiol preparation was taken for up to 24 cycles. Follow-up information was collected 3 to 4 months post-treatment. Bleeding pattern analyses were based on 27,970 valid cycles. Normal cyclic bleeding patterns were experienced by most of the women during the study; only minimal and statistically and clinically insignificant variations in menstrual flow, dysmenorrhea, and premenstrual tension occurred. There was a low incidence of failed withdrawal bleeding in single cycles (less than 1.0% after cycle 6). There were no cases of amenorrhea, defined as two consecutive cycles of missed withdrawal flow. The incidence of breakthrough bleeding or spotting was highest during the initial treatment cycles and diminished with continued use of the formulation. The mean incidence of breakthrough bleeding was 2.36% in cycles 13 to 24. Apart from somewhat higher initial percentages among women new to oral contraception, the pattern of midcycle bleeding or spotting was similar to that of all women studied. Effective long-term cycle control was demonstrated in women who used this OC agent.

Adolescent↗
PubMed1992

[Pharmacological treatment of neuropathic pain].

Neuropathic pain, i.e., pain resulting from functional changes in peripheral and central pathways subsequent to injury to the peripheral nervous system, offers a most difficult challenge to therapy. To date, only the antidepressants and the anticonvulsants have shown any effectiveness, albeit incomplete and inconsistent, and many questions remain unanswered: What are the exact indications for the antidepressants? What component of neuropathic pain do they relieve, and through which mechanisms? Which type of antidepressants should be prescribed? A first-generation tricyclic? Or a new compound with a selective action on serotonin reuptake? What are the effective dosage and duration of the treatment? What is it mechanism of action? What other antalgic effects do carbamazepine and baclofen possess apart from their action on trigeminal neuralgia? The opiates are generally considered to be without effect, but recent clinical and experimental findings seem to point otherwise. In the meantime, following a few simple rules will optimize the benefit of drug treatment in neuropathic pain: treatment tailored to individual cases; adequate dosage and duration of treatment. However, it is from the near future that breakthroughs are being expected, dues to the multiplication of animal models and more accurate analysis; new clinical evaluation tools which help in distinguishing the different mechanisms underlying the various aspects of pain; the development of new substances, such as capsaicin, local anesthetics, anti-inflammatory agents (NSAIDs for example); and better defined methodological conditions for therapeutic trials.

Anesthetics, Local↗
PubMed1991

[Adsorption of pesticides on synthetic adsorption polymers].

On the basis of adsorption of selected pesticides on synthetic adsorption polymers it has been shown that both the adsorption balances as well as kinetics and dynamics of the adsorption strongly depend on the concentration of hydrogen ions of the liquid phase. The dependence of adsorption isotherms on pH value was demonstrated with sufficient accuracy by resorting to the models having been suggested on the ground of IAS theory and the potential one. The kinetic investigations have revealed that the surface diffusion proceeds extremely rapidly in pH ranges that lodge between sorptive pK value and the isoelectric point of the adsorbent surface. The known solutions of transportation and balance equations, which in this case were transferred on the pH-dependent adsorption processes, were implemented for simulating the breakthrough curves. The investigation, covering the effect of the presence of heavy metals in a solution exerted on the pesticides adsorption properties, has shown that the formation of model-pesticide type connections improves the adsorption properties of pesticides to a lesser or greater extent.

2,4-Dichlorophenoxyacetic Acid↗
PubMed1986

[Possibilities of preventing childhood schizophrenia].

The authors consider poorly studied questions of childhood schizophrenia prophylaxis (primary, secondary, individual, and social). At present it is virtually impossible to speak about primary and individual prophylaxis of childhood schizophrenia as an endogenic disease. Preventive measures of reduction of birth rates in groups of patients and individuals at a high risk of the disease should be considered as social prophylaxis aimed at decreasing the prevalence of this disease in the population and complicated by relevant deontological problems. Secondary (therapeutic) prophylaxis of infantile schizophrenia holds promise, due to the fact that the predictions of its outcome are not altogether gloomy and prophylactic treatment runs a favourable course in more than half the cases. Prospects of secondary (therapeutic) prophylaxis of childhood schizophrenia are steadily improving due to the breakthroughs of modern therapy.

Child↗
PubMed1979

Angiography of malignant fibrous histiocytoma of bone.

Angiograms of 10 cases of malignant fibrous histiocytoma of bone were reviewed and correlated with surgical and pathological findings. Nine tumors were hypervascular. Seven demonstrated malignant characteristics (laking in one and coarse tumor vessels in 6). Seven tumors displaced adjacent normal vessels. All angiograms accurately delineated soft-tissue masses and cortical breakthrough but intraosseous extent was less clearly defined. Tumor thrombi within draining veins were evident retrospectively in one instance. Angiography in these cases contributed substantially to surgical management.

Angiography↗
PubMed2002

Biofeedback therapy expedites the resolution of reflux in older children.

PURPOSE: In older children the spontaneous resolution rate of low grade vesicoureteral reflux is low and currently its management is controversial in regard to surgery versus prophylaxis versus observation alone. Bladder dysfunction in children with neurogenic bladders and to a less declarative degree in neurologically intact children has a role in the etiology or persistence of reflux. We determine the impact of biofeedback therapy on neurologically intact children with vesicoureteral reflux and detrusor-sphincter dyssynergia. MATERIALS AND METHODS: Vesicoureteral reflux was detected by voiding cystourethrography in children evaluated for urinary tract infections. Children with breakthrough infections or dysfunctional voiding based on history underwent uroflowmetry with concomitant patch electromyography of the external sphincter. Dyssynergia was defined as increased or steady electromyography activity during micturition. Biofeedback was initially performed weekly and the interval increased as indicated. The goals were to eliminate dyssynergia and reduce or eliminate post-void residual urine. Voiding cystourethrography was performed 1 year later to determine the status of the reflux. Ureteral reimplantation was performed during the period of biofeedback when indicated. RESULTS: From February 1997 to March 2001, 25 children 6 to 10 years old (mean age 9) with vesicoureteral reflux and detrusor-sphincter dyssynergia were treated with biofeedback therapy. There were 31 units (5 bilateral) with reflux, which was grade I in 10, II in 15, III in 5 and IV in 1. Children underwent an average of 7 sessions of biofeedback (range 2 to 20). On followup voiding cystourethrography, vesicoureteral reflux resolved in 17 units (55%), grade improved in 5 (16%) and reflux remained unchanged in 9 (29%). All cured vesicoureteral reflux was grade I (8 cases) or II (9). Four children (5 renal units) underwent reimplantation. In cured children there were no breakthrough infections during or since therapy and post-void residual urine decreased from an average of 40% before to 10% after therapy. Symptoms of urgency, daytime wetting and hoarding of urine improved or were eliminated in all children with resolved vesicoureteral reflux. CONCLUSIONS: Treating external detrusor-sphincter dyssynergia in older children with low grade vesicoureteral reflux, with biofeedback results in 1-year resolution rates that are considerably greater than historical resolution rates. External detrusor-sphincter dyssynergia should be screened for in children when surgery or discontinuation of chemoprophylaxis is considered so that biofeedback can be started.

Biofeedback, Psychology↗
PubMed2000

Haemorrhagic complication after total extirpation of huge arteriovenous malformations.

Two cases with huge arteriovenous malformations (AVMs) who developed haemorrhagic complications after surgery are described. The cause of the postoperative haemorrhage was considered to be the normal perfusion pressure breakthrough phenomenon and/or occlusive hyperaemia. These two haemodynamic insults possibly occur simultaneously and induce life-threatening haemorrhage. It was concluded that a huge high-flow AVM with a large venous ampulla in its deep drainers has a high risk of a postoperative intravenous thrombosis, resulting in haemorrhage together with normal perfusion pressure breakthrough phenomenon.

Adult↗
PubMed2001

Childhood vaccination against varicella: persistence of antibody, duration of protection, and vaccine efficacy.

OBJECTIVE: To document the duration of protection afforded by Oka/Merck varicella vaccine over a 7-year period. STUDY DESIGN: The subjects were healthy children 1 to 12 years of age originally enrolled in clinical studies to evaluate the primary immune response to varicella vaccine 6 weeks after vaccination. Each was monitored for antibody persistence, breakthrough infection, and household exposure to varicella to produce estimates of vaccine efficacy. RESULTS: The 6-year cumulative varicella antibody persistence rate was 99.5% (95% CI: 98.9%, 100.0%). The annual breakthrough rate through 7 years ranged from 0.2% to 2.3% per year; the estimated cumulative event rate was 6.5%. Comparison of the observed average annual breakthrough rate with the age-adjusted expected annual incidence rate of varicella in unvaccinated children corresponded to an estimated vaccine efficacy of 93.8% to 94.6%. Eighty vaccinated children were exposed to varicella in the household, resulting in 8 (10%) cases of infection. When compared with the historical attack rate of 86.8% in unvaccinated susceptible persons exposed to varicella in the household, this yields an estimated vaccine efficacy of 88.5% (95% CI: 80.9%, 96.1%). Varicella cases in vaccinated children generally were mild. CONCLUSION: The live attenuated varicella vaccine is highly effective in inducing persistent immunity and long-term protection against breakthrough varicella infection.

Age Distribution↗
PubMed1978

Interpretation of the body surface isopotential maps of patients with right bundle branch block. Determination of the region of the delayed activation within the right ventricle.

Body surface isopotential maps were produced by computer processing of the 85 electrocardiograms obtained from the entire thorax of 28 patients with complete or incomplete right bundle branch block (RBBB). We divided the map patterns into the following 3 groups. Type I map pattern (10 cases): at the early stage of QRS, the maximum was located in the left chest. It shifted to the left from the normal position; at the instant of 44 msec, on the average, after the onset of QRS breakthrough minimum appeared over the left chest. Its appearance was delayed and its site shifted to the left as compared with the normal; at the late stage, the positive zone covered extensively the right chest and the right back; terminally, the maximum was positioned along the right parasternum. Type II map pattern (13 cases): at the early stage of QRS, the maximum was in the left chest as in Type I; breakthrough minimum appeared at 38 msec on the average, later than in the normal, but the site of breakthrough minimum varied from the left chest as in Type I to the midsternal region as in the normal; at the late stage, the positive zone covered the upper part of the right chest and the right back, less extensively than in Type I; the terminal maximum was in the upper sternal region. Type III map pattern (5 cases): the map pattern passed normally until the late stage, but thereafter a small positive zone survived over the upper sternal region. In Type I the delayed activation was presumed to occur all over the right ventricle, in Type II mainly over the smaller area of the right anterior free wall, and in Type III over the localized area of the outflow tract. Patients with complete RBBB showed Type I pattern. Patients with incomplete RBBB showed Type II or Type III pattern, although electrocardiograms failed to differentiate Type II patients from Type III patients. These findings suggest that the electrocardiographic pattern of incomplete RBBB probably arises from the various mechanisms.

Adult↗