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1.
We studied the evolution of chronic Chagas' disease in 107 patients with a positive Guerreiro-Machado reaction and 22 non-chagasic, non-heart disease control subjects for a follow-up period of 3 to 10 years (mean follow-up of 4.9 years). After completion of invasive and non-invasive studies, chagasic patients were classified into four groups: IA (normal ECG, without heart disease; 18 patients); IB (normal ECG, early left ventricular segmental abnormalities; 13 patients); II (abnormal ECG, advanced myocardial damage, no signs of heart failure; 42 patients); and III (abnormal ECG, end-stage, congestive heart failure; 34 patients). One out of five group IA patients re-studied with invasive methods evolved to group IB (20%); 4 group IB patients evolved to group II (33%) and 6 group II patients evolved to group III (15%). The life expectancy of patients in groups IA and IB (normal ECG) was similar to that of our control group, whereas in groups II and III it was significantly decreased (P less than 0.001). Nine group II patients (23%) and 28 group III patients (82%) died during the follow-up period. Main terminal events were refractory congestive heart failure, sudden death and systemic thromboembolism. Our findings suggest that chronic Chagas' disease follows an evolutionary course from asymptomatic, normal ECG group I stage to arrhythmic (II) and congestive (III) stages. Subjects with a positive Guerreiro-Machado reaction showed a significantly lower life expectancy than our control group, but only when clinical and/or ECG abnormalities were identified.  相似文献   
2.
OBJECTIVE: The present work analysed endomyocardial biopsies of patients with acute Chagas' disease in order to evaluate the frequency and intensity of T. cruzi antigens, CD4+ and CD8+ T cells to determine the characteristics of this recurrent disease in Venezuela. MATERIAL AND METHODS: Twelve endomyocardial biopsies of patients with Chagas' disease, 12 to 51 years old, (7M and 5F) were analysed. T. cruzi antigens and CD4+ (helper) and CD8+ (cytotoxic-suppressor) T cells were detected by the immunoperoxidase technique.The presence and intensity of lymphocytic myocarditis was evaluated according to the degree of myocardial fibre injury caused by inflammatory infiltrate. RESULTS: Myocarditis was present in 100% of the cases. The mean numbers of CD4+ T cell and CD8+ T cell were 11.00 (+/- 10.29); 14.69 (+/- 13.08) and the CD4/CD8 T cell ratio was 0.75. T. cruzi antigens were detected in 58%. There was a good correlation between the numbers of CD4 and CD8 T cells of each case and a lack of correlation with the amount of T. cruzi antigens. CONCLUSION: All patients with acute Chagas' disease show some degree of myocarditis that seems to be directly related to the presence of parasitic antigens. Both CD4 and CD8 T cells participate in this process.We are following these patients to see if patients with severe myocarditis and more parasite antigens in the acute phase will develop chronic heart failure.  相似文献   
3.
Background/AimSeverity of chronic gastritis associated with Helicobacter pylori infection (CGAHpI) could play a role in evaluating the potential risk to develop gastric cancer. Our aim was to estimate the risk for gastric cancer in a clinical setting, according to histopathologic criteria, by applying the gastric cancer risk index (GCRI)MethodsHistopathologic study of the gastric biopsies (corpus-antrum) from consecutive adult patients that underwent gastroesophageal duodenoscopy was carried out, and the GCRI was applied in patients presenting with CGAHpI.ResultsOne hundred eleven patients (77% female) with a mean age of 38.6±13.1 years were included. Active Helicobacter pylori infection (aHpi) was diagnosed in 77 cases (69.40%). In 45% of the cases with aHpi, pangastritis (23%) or corpus-predominant gastritis (22%) was diagnosed. Nine cases were diagnosed with intestinal metaplasia (8%), 7 of which (77.70%) were in the aHpi group. Twenty one percent of the patients with aHpi had a GCRI of 2 (18.10%) or 3 (2.50%) points (high risk index), while 79.10% accumulated a GCRI of 0 or 1 points (low risk index). Of the patients with no aHpi, none of them had 3 points (p=0.001). Of the 18 patients that accumulated 2 or 3 points, 6 (33.30%) presented with intestinal metaplasia (all with pangastritis and corpus-predominant gastritis), of which 4 cases (66.60%) had aHpi.ConclusionsThe estimated gastric cancer risk in patients with CGAHpI in the clinical setting studied was relatively low and 5% of the patients had a histopathologic phenotype associated with an elevated risk for developing gastric cancer.  相似文献   
4.
BACKGROUND: This research was conducted to determine whether the depolarization and repolarization cardiac process of children born at high altitude differs from that of children born at lower altitudes. METHODS: We studied three groups of 30 healthy newborns in the Venezuelan Andes. Group 3500 m consisted of infants born at 3500 m above sea level; Group 3000 m of infants born at 3000 m above sea level and Group 1600 m of infants born at 1600 m above sea level. Conventional 12-lead electrocardiograms were recorded in the 90 newborns. Corrected QT interval, duration from the peak to the end of the T wave, dispersion of QT interval and of the final portion of T wave and heart rate were computed in each subject. RESULTS: The findings of the present study show that infants born at high altitude (Groups 3500 and 3000 m) had a significantly longer corrected QT interval and a significantly shorter peak-to-end of T wave interval. Neither the heart rate nor the indexes of dispersion of the depolarization-repolarization process revealed abnormal values or significant differences among the groups. CONCLUSIONS: These results suggest that the depolarization and repolarization cardiac process of infants born at high altitude differs from that of children born at lower altitudes.  相似文献   
5.
An 18-year-old girl had been suffering from palpitations for 3 years. After a normal and asymptomatic pregnancy, she became highly symptomatic with more than 6 tachycardia paroxysms a week, many of them requiring emergency hospitalizations because of hemodynamic collapse. The electrophysiological evaluation revealed dual A-V nodal pathways and the presence of 4 accessory pathways (3 in the left A-V ring: lateral, posterior, and posteroseptal, 1 right posteroseptal) with 5 types of atrioventricular tachycardia and atrial flutter. The 4 accessory pathways and the slow A-V nodal pathway were successfully ablated, and the patient has been asymptomatic for 12 months without taking antiarrhythmic drugs.  相似文献   
6.

Background

Enhanced recovery after surgery (ERAS) protocols consist of a set of perioperative measures aimed at improving patient recovery and decreasing length of stay and postoperative complications. We assess the implementation and outcomes of an ERAS program for colorectal surgery.

Methods

Single center observational study. Data were collected from consecutive patients undergoing open or laparoscopic colorectal surgery during 2 time periods, 3 years before (Pre‐ERAS) and 2 years after (Post‐ERAS) the implementation of an ERAS protocol. Baseline characteristics of both groups were compared. The primary outcome was the number of patients with 180 days follow‐up with moderate or severe complications; secondary outcomes were postoperative length of stay, and specific complications. Data were extracted from patient records.

Results

There were 360 patients in the Pre‐ERAS group and 319 patients in the Post‐ERAS Group. 214 (59.8%) patients developed at least one complication in the pre ERAS group, versus 163 patients in the Post‐ERAS group (51.10%). More patients in the Pre‐ERAS group developed moderate or severe complications (31.9% vs. 22.26%, p = 0.009); and severe complications (15.5% vs. 5.3%; p < 0.0001). The median length of stay was 13 (17) days in Pre‐ERAS Group and 11 (10) days in the Post‐ERAS Group (p = 0.034). No differences were found on mortality rates (4.7% vs. 2.5%; p = 0.154), or readmission (6.39% vs. 4.39%; p = 0.31). Overall ERAS protocol compliance in the Post‐ERAS cohort was 88%.

Conclusions

The implementation of ERAS protocol for colorectal surgery was associated with a significantly reduction of postoperative complications and length of stay.  相似文献   
7.
Vitamin E and ventricular fibrillation threshold in myocardial ischemia   总被引:1,自引:0,他引:1  
The effect of vitamin E on the ventricular fibrillation threshold was studied in an experimental model of acute myocardial ischemia. An anterior thoracotomy was performed on 23 anesthetized Wistar rats. The ventricular fibrillation threshold was measured. Vitamin E was then administered intravenously to an experimental group (n = 11) and a placebo to a control group (n = 12). The ventricular fibrillation threshold was measured again. Finally, the left anterior descending coronary artery was occluded, producing anteroapical myocardial ischemia. The ventricular fibrillation threshold was measured again. This threshold did not vary significantly when vitamin E or the placebo was administered before occluding the coronary artery but after the occlusion a threshold decrease in the placebo group was observed, whereas no such decrease was manifested in the vitamin E-treated group. The results suggest that vitamin E prevents ventricular fibrillation in acute myocardial ischemia in rats.  相似文献   
8.
With the purpose of studying their clinical and histopathologic evolution, 10 acute chagasic patients with myocarditis diagnosed by endomyocardial biopsy and positive sero-parasitologic methods were evaluated at 11 months (8-21 months) after treatment with oral benznidazole. Four of them were reevaluated 5 years post-treatment (58-68 months). Study protocol consisted of clinical, hemodynamic, echocardiographic, seroparasitologic and histopathologic evaluations. Results showed evidence of persisting myocarditis in 90% and 75% of patients evaluated at 11 months and 5 years respectively, along with asymptomatic, subclinical left ventricular systolic dysfunction being recognized in 75% of patients evaluated 5 years after treatment. All parasitologic studies became negative during follow-up, but serology remained positive for Trypanosoma cruzi antibodies in 80% and 75% of patients studied at 11 months and 5 years. In conclusion, myocardial damage was constantly found in our acute chagasic patients. Treatment with benznidazole eliminated symptoms and parasitemia, but it does not seem to alter favorably the histopathological evolution of the chagasic cardiac disease.  相似文献   
9.
1 The cataleptic and monoamine-depleting effects of a butyrophenone derivative (4'-fluoro-4-[[4-(p-fluorophenyl)-3-cyclohexen-1-yl]-amino]-butyrophenone hydrochloride, U-32, 802A) were studied in rats and mice and compared with those of tetrabenazine. 2 Catalepsy was evaluated by means of a modified grid test which allowed the repetition of the test in the same animal several times without affecting the results. Both drugs produced a dose-related cataleptic state of similar time course. 3 Like tetrabenazine, U-32, 802A induced a large reduction in the content of 5-hydroxytryptamine, dopamine and noradrenaline in different parts of the brain, with a concomitant elevation in the metabolites 5-hydroxyindol-3-yl acetic acid and homovanillic acid. The time courses of the catalepsy and the reduction in brain monoamines were very similar. 4 The activity of U-32, 802A suggested that the drug, although chemically a butyrophenone, might act primarily at the presynaptic organelle for storage of monoamines in a way similar to tetrabenazine.  相似文献   
10.
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