Death occurred due to undiagnosed systemic amyloidosis: a case report.

Abstract: Amyloidosis is a disorder related to errors in protein folding. We present a clinical case of systemic amyloidosis manifesting as hypotension, tachycardia, pain, weight loss, asthenia, anorexia, dysphagia, and mood deflection in a 49-year-old-year-old woman with a previous clinical history of articular and muscular pain, correlated to suspected seronegative arthritis. The blood test revealed kidney insufficiency, an electrocardiogram identified low voltages of the peripheral leads and T waves anomalies. A serum protein electrophoresis revealed the presence of high levels of monoclonal kappa free chains. The woman started to have a sense of suffocation, and after one week she was found dead in her bed. After the autopsy, the results of Congo red staining of the myocardium were characteristic of amyloid. According to the autoptic and the histological examination, death occurred due to acute cardiac and respiratory arrest secondary to amyloid cardiomyopathy in a patient with undiagnosed systemic amyloidosis.

The evolution of the autopsy over the years.

Abstract: Autopsy has played an extremely important role in both the forensic and clinical fields for many years. In recent years, clinical autopsy has become less important, but today, thanks to the pandemic, this importance has been rediscovered. Conversely, forensic autopsy has never lost its importance, but it would need to be updated.

Susceptibility, Oviposition Preference, and Biology of Grapholita molesta (Lepidoptera: Tortricidae) in Prunus Spp. Rootstock Genotypes.

Studying the susceptibility of peach trees to Grapholita molesta (Busck) is one of the major steps in the development of pest-resistant peach varieties. This work evaluated the susceptibility of 55 genotypes of the "Prunus Rootstock Collection" ("Coleção Porta-enxerto de Prunus") of Embrapa Temperate Climate (Pelotas, Rio Grande do Sul, Brazil) to the natural infestation of G. molesta, assessed the oviposition preference of G. molesta in choice and no-choice bioassays, and estimated the biological parameters and the fertility life table on different Prunus spp. genotypes in the laboratory. Genotypes Prunus kansuensis (Rehder), I-67-52-9, and I-67-52-4 were the most susceptible to G. molesta infestation in the field (>60% of branches infested), while 'Sharpe' (Prunus angustifolia x Prunus spp.) and Prunus sellowii (Koehne) were the least infested (0% of branches infested). In choice and no-choice bioassays, G. molesta preferred to oviposit on P. kansuensis when compared with Sharpe. The Sharpe genotype also showed an antibiosis effect, resulting in negative effects on the fertility life table parameters when compared with the genotypes P. kansuensis and 'Capdeboscq.' The results found in the present study can provide information to initiate a long-term breeding program moving desired G. molesta resistance traits from the rootstock into the Prunus spp. cultivars.

Mn concentration and quantum size effects on spin-polarized transport through CdMnTe based magnetic resonant tunneling diode.

Theoretical studies on spin-dependent transport in magnetic tunneling diodes with giant Zeeman splitting of the valence band are carried out. The studied structure consists of two nonmagnetic layers CdMgTe separated by a diluted magnetic semiconductor barrier CdMnTe, the hole is surrounded by two p-doped CdTe layers. Based on the parabolic valence band effective mass approximation and the transfer matrix method, the magnetization and the current densities for holes with spin-up and spin-down are studied in terms of the Mn concentration, the well and barrier thicknesses as well as the voltage. It is found that, the current densities depend strongly on these parameters and by choosing suitable values; this structure can be a good spin filter. Such behaviors are originated from the enhancement and suppression in the spin-dependent resonant states.

Electronic and magnetic properties of Mn-doped BeSiAs(2) and BeGeAs(2) compounds.

The structural, electronic and magnetic properties of BeSiAs(2) and BeGeAs(2) chalcopyrite ternary compounds doped with manganese were investigated by means of ab initio calculations. It was found that substitution of Be atoms by Mn increases the lattice constants of both compounds that provide acceptable mismatch with conventional Si, Ge and GaAs substrates. In spite of the increase of the spin polarization upon doping, both compounds possess antiferromagnetic (AFM) ordering with the impurity in the group II position whereas ferromagnetic (FM) ordering is obtained in the case of an impurity in the group IV position.

Diagnostic electrocardiography in epidemiological studies of Chagas' disease: multicenter evaluation of a standardized method.

An electrocardiographic recording method with an associated reading guide, designed for epidemiological studies on Chagas' disease, was tested to assess its diagnostic reproducibility. Six cardiologists from five countries each read 100 electrocardiographic (ECG) tracings, including 30 from chronic chagasic patients, then reread them after an interval of 6 months. The readings were blind, with the tracings numbered randomly for the first reading and renumbered randomly for the second reading. The physicians, all experienced in interpreting ECGs from chagasic patients, followed printed instructions for reading the tracings. Reproducibility of the readings was evaluated using the kappa (kappa) index for concordance. The results showed a high degree of interobserver concordance with respect to the diagnosis of normal vs. abnormal tracings (kappa = 0.66; SE 0.02). While the interpretations of some categories of ECG abnormalities were highly reproducible, others, especially those having a low prevalence, showed lower levels of concordance. Intraobserver concordance was uniformly higher than interobserver concordance. The findings of this study justify the use by specialists of the recording of readings method proposed for epidemiological studies on Chagas' disease, but warrant caution in the interpretation of some categories of electrocardiographic alterations.

Age-related changes in sympathetic activity: biochemical measurements and target organ responses.

The aim of this study was to evaluate using several parameters the effect of aging on sympathetic nervous system activity. We measured heart rate, skin conductance level and free and total plasma catecholamines in 60 normal subjects aged 20-80 years, divided into three age groups, in basal supine conditions and in response to standing and to hyperventilation. Basal heart rate was similar in all subjects and failed to correlate with age. Skin conductance level decreased with increasing age and correlated negatively and significantly with age. In response to standing and to hyperventilation, heart rate and skin conductance level increased in all groups but the values attained became lower in older subjects. Basal free and total norepinephrine (NE) and total epinephrine (E) correlated positively and significantly with age. In response to standing, free NE determined at the peak heart rate response, increased significantly only in young subjects. In response to hyperventilation free and total NE increased in all subjects. In conclusion, our study supports and extends previous findings that sympathetic nervous system activity is altered in aging. Moreover, these data also show that biochemical measurements of sympathetic nerve activity do not reflect the same alterations as those involving target organ responses.

Outpatient vs inpatient pacemaker implants, thresholds and complications

Since new development of active and passive fixation electrodes with low dislodgement rates, we started ambulatory pacemaker implantation. Over a period of 19 months 124 patients were treated, 79 of them were treated as outpatients. We selected for the inpatient group, patients who were already in the intensive care unit, those absolutely pacemaker dependent or those who had difficulties during implantation. An ECG was recirded unneduateky after the implant. We compared atrial and ventricular threslds at implant and one month later, dislodgements and major complications. The results show that ambulatory surgery compard with inpatient surgery has the same rate of complications.

Superior vena cava occlusion and/or syndrome related to pacemaker leads.

Four cases of pacemaker-related SVC obstruction or syndrome are reported. While two of them lacked any symptom suggestive of SVC obstruction, the other two presented with mild symptoms. None of them received any treatment. One died from a cause unrelated to SVC obstruction, while the others presented no change in their clinical status. A review of the literature suggests that neither thrombotic nor fibrotic obstruction in patients with pacemaker leads is strictly related to the number of abandoned leads, the presence of severed leads, or the time elapsing from pacemaker implant. The diagnosis is clinically made and is confirmed by venography. Only one of the reported deaths is attributable to SVC obstruction. The remaining cases from the literature responded to treatment with heparin, thrombolytic agents, angioplasty, or surgery.

Left posterior hemiblock related to an interventricular septum tumour. First case in the literature.

A 22-year-old man who engaged in intense and regular physical exercise complained of atypical chest pain. The only remarkable abnormality found in the routine clinical work-up was a left posterior hemiblock. The echocardiogram and the magnetic resonance imaging (MRI) study showed a tumour in the posterior and superior aspect of the interventricular septum where the posterior fascicle of the left bundle is located. It was interpreted that the left posterior hemiblock was produced by the tumour.

[An evaluation of transesophageal atrial pacing for studying the use-dependence effect of anti-arrhythmia drugs]. / Evaluación de la sobreestimulación auricular transesofágica para el estudio del efecto uso-dependencia de las drogas antiarrítmicas.

Use-dependent effect is characteristic of certain antiarrhythmic drugs, mainly those included in Group I of Vaughan-Williams classification. There is an increasing interest in the study of this phenomenon in order to correlate it with the potential arrhythmogenic effect of currently used antiarrhythmic drugs. Use-dependent effect produces widening of the QRS ECG complex as the heart rate is increased. Thus, to produce the necessary changes in heart rate to clinically disclose this phenomenon, endocardial stimulation of the right ventricle is usually done both in control condition and under the effect of the tested drug. As this is an invasive method, the amount of information collected on this important aspect of the antiarrhythmic drug effects has been limited. Hence, we decided to confirm whether transesophageal cardiac pacing is a suitable method to produce controlled changes of the heart rate in order to analyse the use-dependent phenomenon. In this study we included 14 patients, 9 women and 5 men aged 47.85 +/- 13.91 years and ejection fraction of 54.64 +/- 7.19%. Transesophageal stimulation was performed up to the Wenckebach point and the previous rate producing 1:1 A-V response was considered. ECG was recorded in an ink-jet three-channel electrocardiograph at 100 mm/sec chart speed and QRS duration was measured. All patients were studied in the basal unsedated state, free of any medication and after the administration of 3.13 +/- 0.74 mg/kg of flecainide during 4.07 +/- 1.4 days. Atrial capture was obtained with pulses of 15 mA and 18 msec. Heart rate attained before treatment was 150 +/- 21.83 bpm and 144.28 +/- 19.88 bpm under the effect of flecainide (p = NS) (Table 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluación de la sobreestimulación auricular transesofágica para el estudio del efecto uso-dependencia de las drogas antiarrítmicas. / [An evaluation of transesophageal atrial pacing for studying the use-dependence effect of anti-arrhythmia drugs]

Use-dependent effect is characteristic of certain antiarrhythmic drugs, mainly those included in Group I of Vaughan-Williams classification. There is an increasing interest in the study of this phenomenon in order to correlate it with the potential arrhythmogenic effect of currently used antiarrhythmic drugs. Use-dependent effect produces widening of the QRS ECG complex as the heart rate is increased. Thus, to produce the necessary changes in heart rate to clinically disclose this phenomenon, endocardial stimulation of the right ventricle is usually done both in control condition and under the effect of the tested drug. As this is an invasive method, the amount of information collected on this important aspect of the antiarrhythmic drug effects has been limited. Hence, we decided to confirm whether transesophageal cardiac pacing is a suitable method to produce controlled changes of the heart rate in order to analyse the use-dependent phenomenon. In this study we included 14 patients, 9 women and 5 men aged 47.85 +/- 13.91 years and ejection fraction of 54.64 +/- 7.19

. Transesophageal stimulation was performed up to the Wenckebach point and the previous rate producing 1:1 A-V response was considered. ECG was recorded in an ink-jet three-channel electrocardiograph at 100 mm/sec chart speed and QRS duration was measured. All patients were studied in the basal unsedated state, free of any medication and after the administration of 3.13 +/- 0.74 mg/kg of flecainide during 4.07 +/- 1.4 days. Atrial capture was obtained with pulses of 15 mA and 18 msec. Heart rate attained before treatment was 150 +/- 21.83 bpm and 144.28 +/- 19.88 bpm under the effect of flecainide (p = NS) (Table 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluación de la sobreestimulación auricular transesofágica para el estudio del efecto uso-dependencia de las drogas antiarrítmicas. / [An evaluation of transesophageal atrial pacing for studying the use-dependence effect of anti-arrhythmia drugs]

Use-dependent effect is characteristic of certain antiarrhythmic drugs, mainly those included in Group I of Vaughan-Williams classification. There is an increasing interest in the study of this phenomenon in order to correlate it with the potential arrhythmogenic effect of currently used antiarrhythmic drugs. Use-dependent effect produces widening of the QRS ECG complex as the heart rate is increased. Thus, to produce the necessary changes in heart rate to clinically disclose this phenomenon, endocardial stimulation of the right ventricle is usually done both in control condition and under the effect of the tested drug. As this is an invasive method, the amount of information collected on this important aspect of the antiarrhythmic drug effects has been limited. Hence, we decided to confirm whether transesophageal cardiac pacing is a suitable method to produce controlled changes of the heart rate in order to analyse the use-dependent phenomenon. In this study we included 14 patients, 9 women and 5 men aged 47.85 +/- 13.91 years and ejection fraction of 54.64 +/- 7.19

. Transesophageal stimulation was performed up to the Wenckebach point and the previous rate producing 1:1 A-V response was considered. ECG was recorded in an ink-jet three-channel electrocardiograph at 100 mm/sec chart speed and QRS duration was measured. All patients were studied in the basal unsedated state, free of any medication and after the administration of 3.13 +/- 0.74 mg/kg of flecainide during 4.07 +/- 1.4 days. Atrial capture was obtained with pulses of 15 mA and 18 msec. Heart rate attained before treatment was 150 +/- 21.83 bpm and 144.28 +/- 19.88 bpm under the effect of flecainide (p = NS) (Table 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Lack of correlation between the coupling interval of ventricular premature beats and the preceding cycle length.

The accepted variation of 80-120 ms in the coupling interval of non-parasystolic ventricular premature beats has been linked to the duration of the preceding cycle length, but a lack of correlation between these factors has often been found. As a result, there is no explanation for variations in the coupling interval of such ventricular premature beats. To analyze the influence of the preceding cycle length on the coupling interval of isolated ventricular premature beats throughout an entire day, 10 otherwise healthy patients with frequent monofocal non-parasystolic isolated ventricular premature beats were studied with Holter recordings. A sample of the electrocardiogram was obtained at the beginning of each quarter of an hour and coupling intervals as well as preceding cycle lengths of ventricular premature beats not belonging to a bigeminy or trigeminy sequence were measured. Preceding cycle lengths changed in a way similar to the prevailing heart rate, with a marked prolongation during sleep. Coupling intervals showed an irregular pattern during the waking period but increased consistently from the first to the last hour of sleep. The average coupling interval during sleep was significantly longer than during waking (439 +/- 74 vs 466 +/- 80, p less than 0.01). In each patient a similar preceding cycle length within a narrow range of 40 ms was searched for during waking as well as during sleep and the corresponding coupling intervals were significantly longer during sleep (446 +/- 80 vs 466 +/- 85, p = 0.009).(ABSTRACT TRUNCATED AT 250 WORDS)

Transarterial permanent pacing of the left ventricle.

Clinical evaluation of a 64-year-old male patient with a permanent pacemaker showed a right bundle branch block in his ECG that led to the suspicion of catheter misplacement. A two-dimensional echocardiogram and bilateral venogram demonstrated that the pacemaker lead was not in the venous system and that its course was from the axillary artery to the left ventricle passing through the aortic valve. Thirty-three days after implant, replacement of the pacemaker lead through the venous system to stimulate the right ventricular endocardium was performed. At 7 month follow-up the patient has had no complication from his previous arterial pacemaker implantation.

Clinical assessment of the right ventricle anterior papillary muscle extrasystoles with Holter recordings.

To assess the short-term behavior of the right ventricle anterior papillary muscle extrasystoles (APME) based on Holter recording and exercise data, 20 subjects (age 31.5 +/- 13.7 years) with otherwise normal electrocardiogram were studied. APME was diagnosed when it resembled LBBB morphology, with downward oriented AQRS in the frontal plane, slurred r wave in lead V1, and an R/S ratio less than 1 in this same lead. Except for palpitations in ten patients, there were no other symptoms related to the arrhythmia. Two Holter recordings, 30 to 330 days apart, were performed and their results compared. In the first Holter recording, the average rate of VPB/minute was 9.9 +/- 2.5 (xg +/- SD). Half of the patients had couplets and five had ventricular tachycardia. In the second Holter recording, the average rate of VPB/minute was 8.7 +/- 3. In eight cases, couplets were recorded, in half of which one or more episodes of ventricular tachycardia were also noted. Six patients showed another VPB morphology distinct from APME. Stress test suppressed VPB in 10/13 patients, couplets in 2/3 and ventricular tachycardia in the only one with this arrhythmia at the start of the test. Repetitive forms vs APME frequency and vs heart rate exhibited an inverse relationship. We conclude that APME is a clinical condition with both high and stable VPB levels, which can be found in subjects with otherwise normal hearts and in the short-term has a spontaneous uncomplicated outcome.

Dynamics of transmission of Trypanosoma cruzi in a rural area of Argentina. IV. Serologic, parasitologic and electrocardiographic study of the human population.

A serologic and electrocardiographic study was carried out in people living in 18 households in La Invernada (LI), Departamento Figueroa, and in 20 houses in Amamá (A), Departamento Moreno, both in the province of Santiago del Estero, Argentina. Serological tests performed were indirect hemagglutination (IHAT) and indirect immunofluorescence antibody tests (IFAT). Complement fixation, direct agglutination and ELISA tests were also done for those sera, showing discordant results for either IHAT or IFAT. All people in LI and children up to 12 years old in A were studied by xenodiagnosis. Approximately 50% of the whole population was infected (50% in LI and 50.9% in A) and a similar prevalence rate was already recorded in children below 10 years. A moderate increase of infection rates was observed in successively older age groups, indicating that most of the people became infected in the first decade of life. Comparison of serological profiles of both populations suggests a protective effect of insecticidal control campaigns in those individuals born between 1961 and 1971. New surveys carried out in both populations 2 years later rendered a 4 times greater annual incidence rate in A as compared with LI (7.9% vs 1.8% respectively). No differences were found in the percentages of abnormal electrocardiograms among seropositive and seronegative individuals from both settlements. The prevalence of complete right bundle branch block (RBBB) was higher in seropositive than in seronegative people (4.8% vs 2.3%) but lower than those figures recorded for other parts of the country and the continent. This suggests that in spite of its high prevalence, Chagas' disease has low morbidity in both localities.