Biological activity of 1,2,3-triazole-2-amino-1,4-naphthoquinone derivatives and their evaluation as therapeutic strategy for malaria control

Malaria can be caused by several Plasmodium species and the development of an effective vaccine is challenging. Currently, the most effective tool to control the disease is the administration of specific chemotherapy; however, resistance to the frontline antimalarials is one of the major problems in malaria control and thus the development of new drugs becomes urgent. The study presented here sought to evaluate the antimalarial activities of compounds derived from 2-amino-1,4-naphthoquinones containing 1,2,3-triazole using in vivo and in vitro models. 1H-1,2,3-Triazole 2-amino-1,4-naphthoquinone derivatives were synthesized and evaluated for antimalarial activity in vitro, using P. falciparum W2 chloroquine (CQ) resistant strain and in vivo using the murine-P. berghei ANKA strain. Acute toxicity was determined as established by the OECD (2001). Cytotoxicity was evaluated against HepG2 and Vero mammalian cell lines. Transmission electron microscopy of the Plasmodium falciparum trophozoite (early and late stages) was used to evaluate the action of compounds derived at ultra-structural level. The compounds displayed low cytotoxicity CC₅₀ > 100 μM, neither did they cause hemolysis at the tested doses and nor the signs of toxicity in the in vivo acute toxicity test. Among the five compounds tested, one showed IC₅₀ values in submicromolar range of 0.8 μM. Compounds 7, 8 and 11 showed IC₅₀ values < 5 μM, and selectivity index (SI) ranging from 6.8 to 343 for HepG2, and from 13.7 to 494.8 for Vero cells. Compounds 8 and 11 were partially active against P. berghei induced parasitemia in vivo. Analysis of the ultrastructural changes associated with the treatment of these two compounds, showed trophozoites with completely degraded cytoplasm, loss of membrane integrity, organelles in the decomposition stage and possible food vacuole deterioration. Our results indicated that compounds 8 and 11 may be considered hit molecules for antimalarial drug discovery platform and deserve further optimization studies.

Bridge Graft to a Small Distal Artery after Fistula Ligation for Angioaccess-Induced Ischemia: Report of Two Cases

Angioaccess-induced ischemia is an infrequent but cumbersome problem, because both limb ischemia correction and access salvage should be undertaken during the same procedure. This paper reports two cases that we successfully managed with a bridge graft to a small distal artery after fistula ligation.

Epicardial fat thickness correlates with P-wave duration, left atrial size and decreased left ventricular systolic function in morbid obesity

BACKGROUND AND AIM

Epicardial fat (EF) is increased in obesity and has important interactions with atrial and ventricular myocardium. Most of the evidence in this scenario can be confused by the presence of comorbidities such as hypertension, diabetes and dyslipidemia, which are very common in this population. The influence of EF on atrial remodeling and cardiac function demands further investigation on morbidly obese without these comorbidities.

METHODS AND RESULTS

We prospectively recruited 20 metabolically healthy morbidly obese and 20 normo-weights controls. The maximum P-wave duration (PWD) was analyzed by 12-lead electrocardiogram. Left atrial diameter (LAD), left ventricular ejection fraction (LVEF) and EF thickness (EFT) were evaluated by two-dimensional echocardiography. The mean of maximum PWD and LAD were significantly larger in the obese group as compared to the control group: 109.55 ± 11.52 ms × 89.38 ± 11.19 ms and 36.12 ± 3.46 mm × 31.45 ± 2.64 mm, (p < 0.0001). The mean LVEF was lower in the obese group: 63.15 ± 4.25% × 66.17 ± 3.37% (p < 0.017). The mean EFT was higher in the obese group: 7.72 ± 1.60 mm × 3.10 ± 0.85 mm (p < 0.0001). A positive correlation was found between EFT and PWD (r = 0.70; p = 0.001) and LAD (r = 0.667; p = 0.001). An inverse correlation was found between EFT and LVEF (r = -0.523; p = 0.001). In a multiple multivariate regression analysis the EFT remains correlated with LAD and LVEF.

CONCLUSIONS

In a select group of morbidly obese, the excess of EF had a significant impact on atrial remodeling and cardiac function.

Subclinical right ventricle systolic dysfunction in childhood-onset systemic lupus erythematosus: insights from two-dimensional speckle-tracking echocardiography

Objective

The objective of this article is to evaluate right ventricle strain imaging by two-dimensional speckle-tracking (2DST) in childhood-onset systemic lupus erythematosus (c-SLE).

Methods

Thirty-five c-SLE patients with no signs or symptoms of heart failure and 33 healthy volunteers were evaluated by standard echocardiogram and 2DST. Conventional parameters included tricuspid annular plane systolic excursion (TAPSE), RV tissue-Doppler-derived Tei index and systolic pulmonary artery pressure. Global peak longitudinal systolic strain (PLSS) and strain rate (PLSSR) of RV were obtained by 2DST. Demographic/clinical features, SLEDAI-2K/SLICC/ACR-DI and treatment were also assessed.

Results

The median current age was similar in patients and controls (14.75 vs. 14.88 years, p = 0.62). RV PLSS was significantly reduced in c-SLE (−24.5 ± 5.09 vs. −27.62 ± 3.02%, p = 0.003). Similar findings were observed after excluding patients with pulmonary hypertension (−24.62 ± 4.87% vs. −27.62 ± 3.02%, p = 0.0041). RV PLSS was positively correlated with TAPSE ( r = +0.49, p = 0.0027) and negatively correlated with Tei index ( r = −0.34, p = 0.04) in c-SLE. RV PLSSR was not different comparing patients and controls (−0.65 s−1 ± 0.47 vs. −1.87 ± 0.49 s−1, p = 0.07). Further analysis of c-SLE patients revealed higher frequencies of neuropsychiatric manifestations (39% vs. 0%, p = 0.007) and antiphospholipid antibodies (55% vs. 18%, p = 0.035) in those with RV PLSS ≤ −23.7% vs >−23.7%. No differences were evidenced in demographic data, disease activity/damage or treatments ( p > 0.05).

Conclusions

The present study, using a new and more sensitive technique, revealed subclinical RV systolic dysfunction in c-SLE patients that may have future prognostic implications. The novel association of asymptomatic RV dysfunction with neuropsychiatric manifestations and antiphospholipid antibodies may suggest common physiopathological pathways.

Repeated echocardiographic examinations of patients with suspected infective endocarditis

OBJECTIVE

To study the diagnostic contribution of repeated transthoracic (TTE) and transoesophageal echocardiography (TOE) among patients with suspected infective endocarditis.

METHODS

262 patients with 266 episodes of suspected infective endocarditis were referred for TTE and TOE over three years in a 423 bed university cardiology hospital. Patients were a mean (SD) of 47.6 (17.9) years old. 139 (52.3%) episodes occurred in men and 127 (47.7%) in women. The diagnostic information obtained from repeated TTE and TOE examinations was evaluated relative to the diagnosis of endocarditis.

RESULTS

TTE examinations were repeated in 192 (72.2%) and TOE examinations were repeated in 49 (18.4%) of 266 episodes. A mean of 2.4 TTE and 1.2 TOE examinations were performed for each episode of suspected endocarditis. The second and third TTEs added diagnostic information in 34 (26.7%) and the second and third TOEs added diagnostic information in 25 (19.7%) of 127 episodes with definite endocarditis. After the third TTE or TOE no additional diagnostic information was obtained.

CONCLUSIONS

The diagnostic contribution of repeated TTE or TOE for the diagnosis of endocarditis decreased as the number of repetitions increased. In this setting, the data do not substantiate more than three TTE or TOE examinations as an efficient strategy to increase the diagnostic yield for all but selected patients with suspected endocarditis.

Maintenance of midgut epithelial cells from Dendroctonus valens (Coleoptera: Scolytidae) in vitro

This article describes the culture of epithelial cells from anterior and posterior midgut regions of adult Dendroctonus valens. Culture conditions were established, and cell adherence was improved by means of a new technique that allowed the cells to grow between two glass coverslips. Cytoplasmic projections occur as anterior midgut cells grow to confluence; these projections were not observed in cells of the posterior midgut. The optimal culture medium for the maintenance of these epithelial cells was Roswell Park Memorial Institute 1640 medium at 25 degrees C. Cells in Grace's medium died in 24 h. Cultures did not require CO(2) atmosphere, but culture development was favored by the microaerophilic environment and the dark conditions in which the cells were grown, between the coverslips.

Prevalence of lower limb occlusive vascular disease in outclinic diabetic patients

AIM

The aim of this study was to determine the prevalence and risk factors for peripheral occlusive vascular disease (POVD) in subjects with diabetes mellitus (DM) in Brazil.

METHODS

We evaluated 236 diabetic individuals, in spontaneous demand, representing 471 legs. POVD was assessed by the ankle brachial index (ABI).

RESULTS

The mean age was 62.1 years (range 22-89 years), 52% were male, 93.2% type II DM and the mean time to diagnosis was 7.9 years (range 0-37 years). Sixty percent were hypertensives. In 61% at least one pulse was diminished or absent. The prevalence of ischemia was 18% (ABI<0.9) while 22% had an ABI compatible with high grade arterial calcification (ABI>1.3). Overall less than 1/3 of the cases had the vascular exam that could be considered normal. The ABI was lower in subjects with pulse deficit (p<0.001), and a normal pulse had a negative predictive value for ischemia of more than 90%. Subjects with normal pulses were younger and had a decreased diabetes duration (p<0.001 and p<0.05, respectively). An increase in the duration of the diabetes was associated with a progressive decrease in the ABI (p<0.01). Female gender and hypertension were associated with a reduced ABI (p<0.01 and p<0.05, respectively).

CONCLUSION

There is a high prevalence of POVD in diabetic individuals. The disease is associated with hypertension and female gender and gets worse with increasing duration of the diabetes.

Evaluation of stunned and infarcted canine myocardium by real time myocardial contrast echocardiography

Differentiation between stunned and infarcted myocardium in the setting of acute ischemia is challenging. Real time myocardial contrast echocardiography allows the simultaneous assessment of myocardial perfusion and function. In the present study we evaluated infarcted and stunned myocardium in an experimental model using real time myocardial contrast echocardiography. Sixteen dogs underwent 180 min of coronary occlusion followed by reperfusion (infarct model) and seven other dogs were submitted to 20 min of coronary occlusion followed by reperfusion (stunned model). Wall motion abnormality and perfusional myocardial defect areas were measured by planimetry. Risk and infarct areas were determined by tissue staining. In the infarct model, the wall motion abnormality area during coronary occlusion (5.52 1.14 cm(2) ) was larger than the perfusional myocardial defect area (3.71 1.45 cm (2); P < 0.001). Reperfusion resulted in maintenance of wall motion abnormality (5.45 1.41 cm (2); P = 0.43 versus occlusion) and reduction of perfusional myocardial defect (1.51 1.29 cm (2); P = 0.004 versus occlusion). Infarct size determined by contrast echocardiography correlated with tissue staining (r = 0.71; P = 0.002). In the stunned model, the wall motion abnormality area was 5.49 0.68 cm (2) during occlusion and remained 5.1 0.63 cm (2) after reperfusion (P = 0.07). Perfusional defect area was 2.43 0.79 cm (2) during occlusion and was reduced to 0.2 0.53 cm(2) after reperfusion (P = 0.04). 2,3,5-Triphenyl tetrazolium chloride staining confirmed the absence of necrotic myocardium in all dogs in the stunned model. Real time myocardial contrast echocardiography is a noninvasive technique capable of distinguishing between stunned and infarcted myocardium after acute ischemia.

Regulation of water flux through tropical forest canopy trees: do universal rules apply?

Tropical moist forests are notable for their richness in tree species. The presence of such a diverse tree flora presents potential problems for scaling up estimates of water use from individual trees to entire stands and for drawing generalizations about physiological regulation of water use in tropical trees. We measured sapwood area or sap flow, or both, in 27 co-occurring canopy species in a Panamanian forest to determine the extent to which relationships between tree size, sapwood area and sap flow were species-specific, or whether they were constrained by universal functional relationships between tree size, conducting xylem area, and water use. For the 24 species in which active xylem area was estimated over a range of size classes, diameter at breast height (DBH) accounted for 98% of the variation in sapwood area and 67% of the variation in sapwood depth when data for all species were combined. The DBH alone also accounted for > or = 90% of the variation in both maximum and total daily sap flux density in the outermost 2 cm of sapwood for all species taken together. Maximum sap flux density measured near the base of the tree occurred at about 1,400 h in the largest trees and 1,130 h in the smallest trees studied, and DBH accounted for 93% of the variation in the time of day at which maximum sap flow occurred. The shared relationship between tree size and time of maximum sap flow at the base of the tree suggests that a common relationship between diurnal stem water storage capacity and tree size existed. These results are consistent with a recent hypothesis that allometric scaling of plant vascular systems, and therefore water use, is universal.

Structural and functional characteristics of rat hearts with and without myocardial infarct. Initial experience with Doppler echocardiography

OBJECTIVE

To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction.

METHODS

Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis.

RESULTS

Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89 cm vs.0.64 cm; systolic: 0. 72 cm vs. 0.33 cm) and left atrium (0.55 cm vs. 0.33 cm); thinning of left ventricular anterior wall (systolic: 0.14 cm vs. 0.23 cm, diastolic: 0.11 cm vs. 0.14 cm); increased mitral E/ A wave relation (6.45 vs. 1.95). Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90%) and notching of pulmonary systolic flow (60%) were observed in animals with extensive infarction.

CONCLUSION

Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.

Multiple arterial anomalies in the newborn infant. Echocardiographic and angiographic diagnosis

Multiple arterial anomalies characterized by tortuosity and rolling of the pulmonary arteries and aorta were diagnosed on echocardiography in an asymptomatic newborn infant with a phenotype suggesting Ehlers-Danlos syndrome. These changes were later confirmed on angiography, which also showed peripheral vascular abnormalities. The electrocardiogram showed a probable hemiblock of the left anterosuperior branch, and the chest x-ray showed an excavated pulmonary trunk with normal pulmonary flow.

Association of pulmonary atresia with intact ventricular septum and aortic valve stenosis. Prenatal diagnosis

A rare association of pulmonary atresia with an intact septum was diagnosed through echocardiography in a fetus 32 weeks of gestational age. The diagnosis was later confirmed by echocardiography of the newborn infant and further on autopsy. The aortic valve was bicuspid with a pressure gradient of 81 mmHg, and the right ventricle was hypoplastic, as were the pulmonary trunk and arteries, and the blood flow was totally dependent on the ductus arteriosus.

The value of echocardiography in the diagnosis and followup of rheumatic carditis in children and adolescents: a 2 year prospective study

OBJECTIVE

To evaluate echocardiographic/Doppler findings in patients with rheumatic fever whether or not clinical manifestations of carditis were present, and the followup of these findings 24 months after the acute phase.

METHODS

Twenty-two patients with rheumatic fever (13 boys, 9 girls, mean age 11.0 years) were evaluated at baseline (at diagnosis) and after 3 and 6 mo of disease. Eighteen patients were reevaluated 24 mo later. The assessment included physical and cardiac examination, electrocardiogram, chest radiography, and color ECHO/Doppler performed blindly by different investigators. The control group included 15 healthy children.

RESULTS

We observed clinical carditis in 8 patients (36.4%): Group 1, all with ECHO abnormalities. We observed no clinical cardiac manifestations in 14 patients (Group 2), but 5 (35.7%) had positive ECHO/Doppler abnormalities that persisted at least 6 mo in followup assessments. Mitral and aortic were the most frequently involved valves. In Group 1 we observed normalization of the ECHO/Doppler in 3 patients, improvement in 2, no change in 2, and worsening in one. Twelve of 14 patients without clinical carditis were reevaluated, including the 5 patients with ECHO/Doppler abnormalities during the initial evaluations; normalization or improvement was observed in 2 patients, no change in 2, and worsening in one. We observed no ECHO/Doppler abnormalities in the control group.

CONCLUSION

This blind prospective study suggests the existence of asymptomatic carditis in some patients with rheumatic fever and the role ECHO/Doppler investigation could play in diagnosis and followup.

Right coronary artery fistula with congestive heart failure in the neonate. Doppler echocardiographic diagnosis and closure with detachable balloon

We report here a case of coronary artery fistula in a neonate with clinical signs of heart failure. The electrocardiogram showed signs of left ventricular hypertrophy and diffuse alterations in ventricular repolarization. Chest X-ray showed an enlargement of the cardiac silhouette with an increase in pulmonary flow. After echocardiographic diagnosis and angiographic confirmation, closure of the fistulous trajectory was performed with a detachable balloon with an early and late successful outcome.

Safety of dobutamine-atropine stress echocardiography: A prospective experience of 4,033 consecutive studies

Dobutamine-atropine stress echocardiography (DASE) is an established method and has been shown to be accurate for the detection of coronary artery disease. Still, there are few large clinical studies that analyze the safety of DASE in general or the safety of performing it on an ambulatory basis. Most studies use a target heart rate as the primary end point regardless of whether asymptomatic ischemia occurs. Such studies have shown a serious cardiac event rate of approximately 0.3%. We prospectively studied 4,033 consecutive patients on an ambulatory basis and in the hospital with the use of DASE from July 1991 to December 1998. All tests were performed by an experienced physician, and all clinical and DASE data were stored in a large database organized at the beginning of the study. Dobutamine was infused in scalar doses of 5, 10, 20, 30, and 40 microg/kg per minute in 3-minute stages. Development of a new wall motion abnormality, achievement of 85% of target heart, and end of the DASE infusion protocol were used as an end point. If 85% of the target heart rate was not achieved, atropine was infused up to 1 mg in the absence of myocardial ischemia, which was used in 1,280 studies. There were 3,645 diagnostic tests, and 388 (10%) were found to be nondiagnostic. This result was due to poor image quality in 115 (3%), end of protocol in negative-submaximal examinations in 124 (3%), and limiting side effects in 149 (4%). Thirty-seven percent of the tests showed positive results for myocardial ischemia. Major test-related cardiac complications occurred in 10 (0.25%) patients and included 1 ventricular fibrillation, 1 case of myocardial infarction, and 8 cases of sustained ventricular tachycardia. Atropine poisoning was observed in 5 (0.12%) patients. No deaths occurred as a direct or indirect consequence of DASE. We conclude that dobutamine-atropine stress echocardiography is a reasonably safe method for detection of coronary artery disease in the hospital or in an ambulatory basis. The use of new wall motion abnormality as 1 of the end points may prevent further ischemia-related complications.

Lectin-induced nitric oxide production

Considering that nitric oxide (NO) may be involved in anti-tumoral and anti-parasite lectin effects, in this report we investigated whether lectin induces NO production. Lectins from Canavalia brasiliensis, Dioclea grandiflora, Pisum arvense (PAA), and concanavalin A induced murine peritoneal cells to produce NO in vitro. PAA induced similar levels to that obtained with lipopolysaccharide plus interferon-gamma. NO production by adherent cells was significantly lower than that of unfractionated cells, suggesting a combination of lectin stimuli directly on macrophages and via lymphocyte stimulation. Ex vivo experiments showed that cells stimulated in vivo could maintain NO production in vitro without further stimuli. NO synthesis blockage in vivo can significantly increase cell numbers in draining lymph nodes after lectin injection compared to unblocked controls, suggesting an in vivo association of lectin stimuli and NO production. Taken together these data show that lectins can induce NO production both in vitro and in vivo.

Importance of intraoperative transesophageal echocardiography during coronary artery surgery without cardiopulmonary bypass

The goal of this study was to assess left ventricular segmental wall motion (SWM) abnormalities during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), and its impact on the immediate postoperative outcome. Transesophageal echocardiography was used intraoperatively in 27 patients (mean age 57 years) who had CABG without CPB. Images obtained with a 5-MHz biplane transesophageal echocardiographic probe in the transgastric and transesophageal planes were recorded before, during, and after 48 coronary artery clampings for saphenous vein or internal mammary artery anastomosis. Transthoracic echocardiography was performed 1 day before surgery and on the seventh postoperative day. During the 48 coronary artery clampings, 31 (64%) new SWM abnormalities were found. At the time of chest closure, complete recovery occurred in 16 (50%) segments, partial recovery in 10 (33%), and no recovery in 5 (17%). On the seventh postoperative day the new SWM abnormalities persisted in all 5 segments without recovery at the end of the surgery and in 2 of 10 (20%)segments with partial recovery (group 1). Group 1 had higher variation on the echocardiographic point score index between the beginning and end of surgery, higher enzymatic levels, more ST-T changes on the electrocardiogram, and more clinical problems than group 2 (patients without new SWM abnormalities on the seventh postoperative day) (P < .05). We concluded that new SWM abnormalities of the left ventricle occur during CABG without CPB as assessed by intraoperative transesophageal echocardiography. Persistence of these abnormalities at the end of surgery may be a predictor of SWM dysfunction and clinical problems in the immediate postoperative period.

[Right ventricle-dependent coronary circulation in pulmonary atresia with intact ventricular septum. Absence of origin of the coronary arteries from the aorta]

This report describes the clinical, echocardiographic and angiographic aspects of a five-day old boy with pulmonary atresia and intact ventricular septum. Both the echocardiogram and the aortography did not show any coronary arteries arising from the aorta. Two-dimensional echocardiography was able to identify the coronary arteries originating from the right ventricle and so did the right ventricular angiogram. No retrograde flow into the aorta or pulmonary trunk was identified after opacification of the coronary arteries. As far as we know this is the first case diagnosed by echocardiography, and is a vivid example of the necessity of identifying the coronary arteries in patients with pulmonary atresia and intact ventricular septum.

[Anomalous origin of the right pulmonary artery from the ascending aorta (Hemitruncus)]

The origin of the right pulmonary artery from the ascending aorta is a rare cogenital anomaly, with very few reports in the literature. We describe two cases of this rare malformation, one of them, associated with interruption of the aortic arch (type B). In both cases, the diagnosis was made by two-dimensional echocardiography, with angiographic confirmation in one of them. The origin of the right pulmonary artery was close to the aortic valve, anomaly pathogenetically distinct from the type that arises close to the innominate artery.

Dobutamine stress echocardiography in anomalous left coronary artery

The evaluation of left ventricular function with dobutamine stress echocardiography is described for the first time in a patient with anomalous left coronary artery from the pulmonary trunk during the preoperative and postoperative periods. This method demonstrated signs of myocardial ischemia that were not seen on the resting echocardiogram during the preoperative period and ventricular function recovery after surgical intervention.

[Athlete's heart in elite disabled athletes]

PURPOSE

To assess the prevalence of the athlete's, heart syndrome in elite disabled Brazilians athletes.

METHODS

Seventy-five athletes, age 27.8 +/- 6.7 years, 56 men, with various disabilities (47 physical, 12 visual and 16 cerebral paralysis) underwent clinical, electrocardiographic, vectorcardiographic, ergometric and echocardiographic evaluations.

RESULTS

Athlete's heart signs occurred in 33% of the clinical evaluations, in 55% of the electrocardiograms, in 15% of the vectorcardiograms, and in 5% of the echocardiograms. At least one of these signs was presented in 51% of the athletes. There were 2 or more abnormalities in 46% of the athletes and 4 or more signs in 12%. Exercise test was considered not ischemic in 77% of the subjects. There was right bundle branch block in 23% of the tests.

CONCLUSION

There were two or more athlete's heart syndrome signs in 46% of Brazilian disabled athletes.

[Assessment of left internal thoracic artery anastomosis with left anterior descending coronary artery by Doppler echocardiography]

PURPOSE

To study the value of Doppler echocardiography as a tool for the evaluation of left internal thoracic artery graft (LITAG) patency in patients who underwent coronary revascularization using minimally invasive bypass surgery without extracorporeal circulation.

METHODS

The first 12 consecutive patients were studied after coronary artery bypass surgery using a 5 MHz Doppler transducer. Doppler signals for the systolic and diastolic flow velocities were preferably obtained in the second intercostal space. All patients underwent coronary angiography while hospitalized.

RESULTS

The exam was feasible in 93% of patients. Doppler flow pattern was predominantly diastolic (pattern A) in patients with patent anastomoses (6/7). In patients with occluded anastomoses (4/4) Doppler flow pattern was predominantly systolic (pattern B) (p = 0.003).

CONCLUSION

Internal thoracic artery flow pattern as measured by Doppler echocardiography after minimally invasive coronary artery bypass graft surgery is an accurate method for identifying LITAG patency.

[Patent ductus arteriosus and pulmonary artery endarteritis]

We describe a seven year old girl with echocardiographic diagnosis of pulmonary artery endarteritis as a complication of a patent ductus arteriosus, confirmed at surgery. This case illustrates the necessity of complete surgical resection of the infectious source as a way to avoid other complications such as pulmonary embolism.

[Prognostic value of stress echocardiography by dobutamine combined with atropine]

PURPOSE

To determine the prognostic value of dobutamine-atropine stress echocardiography (DASE).

METHODS

We studied 452 consecutive patients at high risk for coronary artery disease, using DASE. They were followed during a mean period of 23 months.

RESULTS

There were 9 cardiac deaths and 2 acute myocardial infarctions in the group of patients with positive tests, and there were 2 myocardial infarctions and 1 cardiac death in patients with negative DASE.

CONCLUSION

We conclude that DASE reliably identifies patients at high risk for hard cardiac events.

[Prognostic value of stress echocardiography by dobutamine combined with atropine]

PURPOSE

To determine the prognostic value of dobutamine-atropine stress echocardiography (DASE).

METHODS

We studied 452 consecutive patients at high risk for coronary artery disease, using DASE. They were followed during a mean period of 23 months.

RESULTS

There were 9 cardiac deaths and 2 acute myocardial infarctions in the group of patients with positive tests, and there were 2 myocardial infarctions and 1 cardiac death in patients with negative DASE.

CONCLUSION

We conclude that DASE reliably identifies patients at high risk for hard cardiac events.

[Safety and feasibility of dobutamine-atropine stress echocardiography]

PURPOSE

To study the safety and feasibility of dobutamine-atropine stress echocardiography (DASE) in patients with known or suspected coronary artery disease.

METHODS

There were 3,000 DASE that were studied in a prospective fashion. All symptoms and side effects were stored in a data base format.

RESULTS

Major test-related complications observed included one case of myocardial infarction, four cases of sustained ventricular tachycardia and five cases of atropine intoxication. There was no death or ventricular fibrillation as a direct or indirect consequence of the test. The infusion protocol allowed to us to examine patients using beta blockers, and led to 95% feasibility.

CONCLUSION

DASE is a safe and feasible method for the study of patients with suspected or known coronary artery disease.

[Diagnostic accuracy of dobutamine-atropine stress echocardiography]

PURPOSE

To analyze the diagnostic accuracy of dobutamine-atropine stress echocardiography.

METHODS

We studied 304 consecutive patients using dobutamine-atropine stress echocardiography who underwent coronary angiography within a month of the exam. Patients received high dobutamine doses associated or not with atropine.

RESULTS

The global sensitivity was 92%, specificity was 72% and diagnostic accuracy was 87%. Analyzing 120 patients with normal LV function, we found sensitivity of 85%, specificity of 79% and accuracy of 82%.

CONCLUSION

Dobutamine-atropine stress echocardiography is an accurate method for the detection of coronary artery disease.

[Partial atrioventricular septal defect associated with right atrioventricular valve Ebstein's disease]

The association of Ebstein's disease and atrioventricular septal defect is extremely rare with only 13 cases described in the literature and none in our country. We described a 15 year-old girl with echo and angiographic diagnosis confirmed by surgery. The non-identification of one of the lesions could impair planning and surgical results.

Investigation of persistent colonization by Pseudomonas aeruginosa-like strains in a spring water bottling plant

Ninety-seven strains, producing a fluorescent pigment under UV light and/or a green diffusive pigment on cetrimide-naladixic acid agar, were isolated from a spring water bottling plant. These strains were presumptively identified as Pseudomonas aeruginosa, but they could not be confirmed as strains of this species nor identified by the API 20NE identification system. The isolates and reference strains were clustered by computer-assisted whole-cell protein sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The numerical analysis of the protein electrophoregrams resulted in the formation of four clusters at a similarity level of 80% and two unclustered type strains. One cluster included strains isolated during a 4-month period and reference strains of several biotypes of P. fluorescens. The remaining isolates formed another cluster with a very high similarity of level, which included two groups of strains based on biochemical characterization by the API 20NE Test System. Strains were typed by random amplified polymorphic DNA (RAPD)-PCR and two different RAPD patterns were obtained, corresponding to each biochemical profile. This persistent colonization seems to be caused by a single species present in the bottling system, with two clonal origins, not related to P. aeruginosa or to any of the other type strains tested. Partial 16S rDNA sequence of a representative strain of one cluster of isolates had a level of similarity of 99.3% with P. alcaligenes. This study shows that characteristics similar to P. aeruginosa on cetrimide-naladixic acid agar can be exhibited by several groups of fluorescent pseudomonads that do not belong to this species, clearly showing that confirmation tests must be performed before a decision regarding the water quality is made.

[Clinical manifestation of aortopulmonary window as mitral regurgitation caused by secondary dilatation of the valvar anulus]

Two patients with huge aortopulmonary window, both ten months-old, that showed curiously up at a clinical viewpoint, including echocardiography, as a mitral valve regurgitation with a dilated mitral ring secondary to the accentuated blood volume through it, were reported. Early signs of heart failure, accentuated systolic murmur at mitral area and overload of left heart cavities, characterized clinical impression of a congenital mitral insufficiency, in both cases. The correct diagnosis was established at operation and at necropsy study, bringing it to us the need to a more accurate analysis of the different diagnostic elements, especially in anomalies which clinical manifestations show great similarities.

Physiologic multivalvular regurgitation during pregnancy: a longitudinal Doppler echocardiographic study

Valvular function, assessed by Doppler technique, has not been extensively investigated during normal pregnancy. To prospectively study this feature, 18 normal pregnant women were followed during their pregnancies and puerperium, with serial clinical and pulsed-continuous Doppler echocardiographic examinations. In four gestational periods and the puerperium, we analysed: (a) ventricular and atrial dimensions, as well as valve annular diameters; (b) prevalence and characteristics of trivial valvular regurgitations. During pregnancy, slight but significant increases of the four cardiac chamber dimensions and valve annular diameters were observed, except for the aortic ring. The prevalence of physiologic valvular regurgitation in early pregnancy (mitral, 0%; tricuspid, 38.9%; pulmonary, 22.2%; aortic, 0%), was similar to a control group of 18 healthy non-pregnant women. As pregnancy evolved, there was a progressive and significant increase of multivalvular regurgitation, maximal at full-term (mitral, 27.8%; tricuspid, 94.4%; pulmonary, 94.4%, P < 0.05 vs. early pregnancy). Aortic regurgitation was not detected in any stage of pregnancy. In the puerperium, mitral regurgitation resolved, but tricuspid and pulmonary regurgitation were still significantly prevalent (83.3% and 66.7%, respectively, P < 0.05 vs. early pregnancy). It is concluded that physiologic multivalvular regurgitation is frequent in pregnancy, mainly involving right-sided valves in late gestational periods, occasionally persisting in the early puerperium. Chamber enlargement, valve annular dilatation, and increased prevalence of trivial valve regurgitation are time-related events during normal pregnancy, resulting from a reversible cardiac remodeling process induced by physiologic volume overload. These aspects should be considered for a correct interpretation of Doppler echocardiographic findings in pregnant women with suspected heart disease.

Contrast echocardiography during cardiac catheterization in patients with congenital heart diseases

Contrast echocardiography performed during cardiac catheterization has mostly been limited to a few published case reports. We studied 37 patients with congenital heart disease to assess the capability of the method to diagnose cardiac shunts and valve regurgitation. Injections of 5% dextrose in water through an angiographic catheter were made to evaluate septal integrity and valve competence compared with conventional contrast angiography. An overall sensitivity of 93% and specificity of 78% were found. In four cases of atrial septal defect and seven of mitral regurgitation, the sensitivity was 100%. It was slightly lower for eleven cases of ventricular septal defect (91%) and four of patent ductus arteriosus (75%). When assessing aortic, tricuspid and pulmonary valve competence, the method proved to be more sensitive than conventional angiography to detect mild regurgitation. Contrast echocardiography is a sensitive and safe technique that may be used in association with conventional angiography reducing the need for radiographic contrast and ionizing radiation time.

[Submitral left ventricular aneurysm in a Brazilian Indian]

Subvalvar left ventricular aneurysm is a rare disease of unknown etiology, that has been described most often in black Africans. A case of Brazilian indian with heart failure and a murmur of mitral regurgitation is reported. The chest x-ray showed a mild bulge in the left cardiac border and two-dimensional echocardiography demonstrated submitral left ventricular aneurysm, confirmed by left ventricular angiography. Surgical treatment consisted of resection of the aneurysm and mitral valvuloplasty. A perforation of the aneurysm, undetected neither by two-dimensional echocardiography nor by angiography was found at surgery.

[Assessment of pulmonary arterial pressure in adults with Doppler echocardiography]

PURPOSE

To assess the role of pulsed Doppler echocardiography (PDE) in the indirect assessment of pulmonary artery (PA) pressure (P), analysing the pulmonary velocity blood flow curves (PVBFC) profile.

PATIENTS AND METHODS

Sixty-one adults with several kinds of heart disease were submitted to heart catheterization to obtain PAP (systolic, diastolic, mean), and other hemodynamic variables. A PDE examination was performed in all to obtain the PVBFC at the level of the pulmonic annulus. Qualitative features of the curve were analysed (morphological pattern, presence of pulmonic regurgitation) as well as quantitative data (acceleration time = AT, right ventricle ejection time = RVET index, AT/RVET index AT corrected for heart rate = ATC), which were compared to the invasive measurements.

RESULTS

An abnormal rapid acceleration of the PVBFC, with triangular configuration, was noted in patient with pulmonary hypertension (PH), in contrast to the dome-like shape of the PVBFC in normal PAP. Pulmonary regurgitation was more frequent (p < 0.05) in patients with severe PH (mean PAP > or = 40 mmHg), comparing with patients with PAP < 40 mmHg. Inverse linear correlations were observed between AT and mean PAP, particularly when sinus rhythm was present (r = 0.89; p < 0.05) excluding patients with atrial fibrillation (19 cases).

CONCLUSION

PDE is an useful and noninvasive method for indirect evaluation of PAP in adults, especially during stable sinus rhythm, in heart rate range from 60 to 115 bpm.

Cardiopulmonary exercise testing early after catheter-balloon mitral valvuloplasty in patients with mitral stenosis

Seven female patients (age 27 to 53 yr) with significant mitral stenosis performed continuous, incremental, maximal treadmill exercise tests the day before and within 3-5 days after catheter-balloon valvuloplasty. Mitral valve area determined by the echo-Doppler method increased from 0.9 +/- 0.3 cm2 to 1.9 +/- 0.7 cm2 (p < 0.02). Mean left atrial pressure was reduced from 24 +/- 8 to 13 +/- 7 mmHg (p < 0.01) and mean pulmonary artery pressure from 36 +/- 13 to 28 +/- 10 mmHg (p < 0.02) with a non-significant increase in cardiac output from 3.6 +/- 1.2 to 4.0 +/- 1.7 l/min. After catheter-balloon valvuloplasty all patients reached a higher maximal workload during exercise, and mean value of oxygen consumption and pulmonary ventilation were significantly lower in submaximal workloads. The calculated ventilatory equivalent for oxygen was significantly reduced in submaximal and in maximal workloads after catheter-balloon valvuloplasty. Peak oxygen consumption and the ventilatory anaerobic threshold were not changed after catheter-balloon valvuloplasty (pre 15.59 +/- 2.72 vs post 16.90 +/- 3.44 and pre 12.10 +/- 2.55 vs post 12.62 +/- 2.71 ml/kg/min, respectively). We concluded that after catheter-balloon valvuloplasty the cost of breathing was reduced and the oxygen consumed was more effectively utilized during exercise. Increases in peak oxygen consumption and in ventilatory anaerobic threshold would require circulatory and metabolic adaptations in response to increased physical activity and were not observed when cardiopulmonary tests were performed early after catheter-balloon valvuloplasty.

Chagas cardiomyopathy and captopril

Chagas disease is a leading cause of heart failure in Latin America. Sudden death occurs in approximately 40% of patients with heart failure due to Chagas disease. We report a single blind, cross-over trial of prolonged treatment with captopril and placebo in 18 Chagas disease patients with class IV NYHA heart failure. Ventricular dimensions, neurohormones, electrolytes and ventricular arrhythmias were analysed in 11 men and seven women receiving stable doses of digoxin and frusemide who were randomly divided into two intervention groups. Group I patients were given increasing doses of captopril up to 150 mg.day-1 maintained for 6 weeks, group II received the placebo. A 24 h Holter, 2-D echocardiogram, urinary catecholamines, plasma renin and electrolyte determinations were performed at the end of each phase. After a 2-week washout period, the two groups crossed over and another period of 6 weeks was observed. Ventricular arrhythmias were analysed by either Mann-Whitney or the Wilcoxon test. Remaining data were assessed by the Student t-test. A significant reduction in heart rate and urinary catecholamine levels, and enhanced plasma levels of renin, together with a reduction in ventricular couplets was found in the captopril-treated group. We conclude that captopril has a beneficial effect on neurohormones with a subsequently reduced heart rate and diminished incidence of ventricular arrhythmias in patients with Chagas disease. This effect might result in a reduction of mortality caused by the disease, suggesting the need for further investigations.

Absence of an aortic valve cusp, a cause of severe aortic regurgitation in infancy

Congenital aortic regurgitation is an extremely rare cardiac lesion. This is a case report of an infant with a severe degree of valve regurgitation due to absence of the noncoronary aortic cusp. We show the echocardiographic, angiographic, and surgical aspects of the case, emphasizing the importance of a precise anatomical diagnosis and the problems of early valve replacement.

Effects of methimazole on low-renal-mass hypertension: changes in blood pressure and pressor responsiveness to vasoconstrictors

The administration of the antithyroid drug methimazole to rats via drinking water prevented the development of hypertension that usually accompanies subtotal nephrectomy and saline drinking (1% NaCl). In methimazole-treated rats, elevated blood pressure induced 5 weeks previously returned to normotensive levels. Pressor responsiveness to angiotensin, vasopressin and norepinephrine in unanesthetized rats was studied after prevention of hypertension in control, low-renal-mass hypertensive (LRM) and low-renal-mass methimazole-treated (LRM-M) rats, and in the reversion study in LRM and LRM-M rats. In LRM rats, responsiveness to vasoconstrictors was increased, whereas responsiveness to vasoconstriction was clearly reduced in LRM-M rats after prevention and reversion studies. These results suggest that (a) thyroid hormones are required in the early and established phases of LRM hypertension, and (b) the decreased pressor responsiveness to vasoconstrictors may play a role in the prevention and reversion of this type of hypertension following methimazole administration. However, the changes in pressor responsiveness may also be secondary to the reduction in blood pressure.

Effects on renal function and digoxin-like immunoreactivity produced by methimazole in low-renal mass hypertension

This study evaluates the effects of methimazole, an antithyroid drug, on blood pressure, digoxin-like immunoreactive factor (DLIF) production and other variables related to salt and water metabolism in low-renal mass (LRM) hypertension. Drinking administration of methimazole (0.025%) from replacement of water by the 1% NaCl solution maintained the blood pressure of low-renal mass rats at normal levels during four weeks after hypertension induction. Serum and urinary excretion of DLIF were significantly increased in LRM rats with respect to controls; in all tests, the highest values of DLIF were found in LRM-methimazole treated (LRM-M) rats. Urinary excretion of DLIF showed positive correlations with diuresis and natriuresis in all three groups (control, LRM and LRM-M rats). However, the correlation between DLIF and sodium disappeared when both factors were expressed as a function of their concentrations. These results indicate that methimazole prevents LRM hypertension and suggest that DLIF might not represent the putative natriuretic hormone. Other findings were that methimazole-treatment reduced renal compensatory hypertrophy subsequent to subtotal nephrectomy, and did not modify the characteristic polyuria-polydypsia in this type of hypertension.

The role of Doppler echocardiography in the diagnosis, follow-up, and management of ventricular septal defects

The defects of the ventricular septum have received special attention from investigators working in echocardiography. The method showed an incomparable capability to identify all the morphological features of the defects. The increasing improvement in definition of transducers associated with conventional and color Doppler contributed significantly to the reliability to detect most of the defects. The great majority of associated lesions can be easily identified and serial examinations allow prediction of which defect may become smaller or even close spontaneously as well as which have acquired deleterious changes in the heart. Several authors have shown very good statistical correlations between echocardiographic indices and hemodynamic parameters in patients with this type of defect. Doppler echocardiography has become an invaluable tool in the diagnosis and follow-up of ventricular septal defect reducing the need for cardiac catheterization and helping management of these patients.

[Pulmonary artery pressure evaluation in adults by Doppler echocardiography]

PURPOSE

To assess the role of pulsed Doppler echocardiography (PDE) in the indirect assessment of pulmonary artery (PA) pressure (P), analysing the pulmonary velocity blood flow curves (PVBFC) profile.

PATIENTS AND METHODS

Sixty-one adults with several kinds of heart disease were submitted to heart catheterization to obtain PAP (systolic, diastolic, mean), and other hemodynamic variables. A PDE examination was performed in all to obtain the PVBFC at the level of the pulmonic annulus. Qualitative features of the curve were analysed (morphological pattern, presence of pulmonic regurgitation) as well as quantitative data (acceleration time = AT, right ventricle ejection time = RVET index, AT/RVET index AT corrected for heart rate = ATC), which were compared to the invasive measurements.

RESULTS

An abnormal rapid acceleration of the PVBFC, with triangular configuration, was noted in patient with pulmonary hypertension (PH), in contrast to the dome-like shape of the PVBFC in normal PAP. Pulmonary regurgitation was more frequent (p less than 0.05) in patients with severe PH (mean PAP greater than or equal to 40 mmHg), comparing with patients with PAP less than 40 mmHg. Inverse linear correlations were observed between AT and mean PAP, particularly when sinus rhythm was present (r = 0.89; p less than 0.05) excluding patients with atrial fibrilation (19 cases).

CONCLUSION

PDE is an useful and noninvasive method for indirect evaluation of PAP in adults, especially during stable sinus rhythm, in heart rate range from 60 to 115 bpm.

[Systemic-pulmonary shunts in congenital heart diseases with decreased pulmonary blood flow: critical analysis of the surgical techniques and immediate results]

PURPOSE

To evaluate immediate postoperative results in children with congenital heart disease and decreased pulmonary blood flow who underwent a systemic to pulmonary shunt.

PATIENTS AND METHODS

Sixty-four patients underwent surgery, 46.8% (30) of them males with ages from 1 day to 17 years old. They were divided in three groups: I--13 pts (20.3%) who underwent classical Blalock-Taussig (BT) shunt; II--46 pts (71.8%) who underwent modified BT shunts, 34 of them with polytetrafluoroetylene (PTFE) and 12 of them with umbilical vein shunts; III--5 pts (7.8%) with central anastomosis that were made with three different types of graft; 3 PTFE, umbilical vein and bovine mammary artery in one each. The simultaneous procedures were: section and suture of PDA--2, closure of systemic-pulmonary collaterals--3, pulmonary valvotomy--3, right ventricular outflow patch--3, pulmonary branch stenosis (enlargement)--2.

RESULTS

In group I there were 4 (30.7%) closures, with two immediate reoperation and a total mortality of 30.7%. In group II there were 4 closures (8.6%) and two reoperations with a mortality of 15.2% (7 cases). In group III there was one graft closure and an overall mortality of 80% (4 pts). When analysing deaths due to the shunt itself the mortality rate was respectively 15.3%, 8.6% and 40.0%.

CONCLUSION

Modified BT operation was performed most frequently in our service; it was associated with less closure and mortality than the other types of shunt. It is considered our first alternative for a systemic-pulmonary shunt.

Left ventricular hypertrophy as a risk factor for arrhythmias in hemodialysis patients

The contribution of left ventricular hypertrophy in determining ventricular arrhythmias (VAS) was studied in 81 chronic renal failure patients in chronic hemodialysis using two-dimensional echocardiographic and electrocardiogram Holter monitoring. The prevalence of LVH was 93% (96% in hypertensive and 87% in normotensive patients). The prevalence of VA was 48%. These arrhythmias were associated with increased cardiac mass, lack of potassium supplementation to the hemodialysis bath, and low K+ and PaO2 during dialysis. Severe forms of VA occurred in 19 of 78 patients, and the risk factors for this occurrence were (a) largely increased cardiac mass indices (exceeding in more than 40% the upper limit of normal for each sex) and (b) prolonged periods of time in hemodialysis treatment (34 +/- 5.5 vs. 17 +/- 2.7 months, p less than 0.05). Changes in potassium or oxygen content of the blood were not significantly associated with the occurrence of severe forms of VA.

Urinary excretion of digoxin-like immunoreactive factor and arginine-vasopressin in rats after several osmotic loads

Urinary digoxin-like immunoreactive factor (DLIF), arginine-vasopressin (AVP) and other urinary parameters were investigated under normal conditions and after the i.p. injection of the following solutions: distilled water, isotonic and hypertonic NaCl, NaHCO3, KCl and urea, at a rate of 3 ml/100 g body weight. The measurement of digoxin-like immunoreactivity by two different radioimmunoassays showed that DLIF was stimulated by all volume loads regardless of the presence or absence of osmolar compounds. This dissociation between DLIF and urinary sodium excretion suggests that DLIF may not constitute the natriuretic hormone. Moreover, a dissociation between DLIF and AVP excretion also were found, which speaks against the hypothesis of a common mechanism of stimulation for both substances.

[Developement and quality control of a radioimmunoassay for measurement of endogenous digoxin]

It has been suggested that sodium renal excretion is regulated, at least partially, by a factor with natriuretic properties called digoxin-like factor (DLF). As this substance crossreacts with digoxin antibodies, it was measured with a radioimmunoassay used to determine exogenous digoxin. Methodological conditions and quality control to determine DLF in plasma and urine have been established. Good correlation coefficients in specificity as well as dilution studies were obtained. Within--and between--assay coefficients of variations indicate good reproducibility. Moreover, changes in plasma DLF levels were detected in patients with cirrhosis or with renal failure, diseases which thrive on alterations in salt and water metabolism. In conclusion, this radioimmunoassay method for measuring DLF may be useful to investigate the role of this factor in several physiological and pathological conditions.

[Fascicular block of the His bundle: critical approach for its identification]

The correct identification of the left and right fascicles blocks of the His bundle will permit to explain different patterns of the ECG and VCG. The differentiation between the right peripheral bundle branch and the left bundle branch division is not only important in anatomic and physiologic grounds, but also in a clinic viewpoint. So, trying to refine the diagnostic criteria and improve the recognition of these intraventricular conduction disturbances, we developed this study. Eighty five patients were evaluated and divided into two groups. Group I included 65 patients with cardiac disease; group II consisted of 20 normal subjects taken as a control. Some classic ECG and VCG criteria were tested as well as new ones. We confirmed the significance of the S2/S3 relation to distinguish the right superior divisional block (RSDB) from the left anterior hemiblock (LAH), and added some new criteria: 1) C morphology in horizontal plane (HP) to the right divisional block (RDB); 2) assessment of aVL lead to separate RSDB from LAH--qR pattern in the last, and different one to RSDB; 3) the qR' pattern in L2, L3 and aVF leads associated with left ventricular hypertrophy (LVH) pattern screened the left posterior hemiblock (LPH). We found no significance in R3/R2 relation to the right inferior divisional block (RIDB). Similarly to what happened to the left bundle branch block in the 70's decade, we expect that an adequate assessment of the RDB can permit a better understanding of its real clinical value.