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.

Potential errors in measurement of nonuniform sap flow using heat dissipation probes

The empirical calibration of Granier-type heat dissipation sap flow probes that relate temperature difference (DeltaT) to sap velocity (v) was reevaluated in stems of three tropical tree species. The original calibration was confirmed when the entire heated probe was in contact with conducting xylem, but mean v was underestimated when part of the probe was in contact with nonconducting xylem or bark. Analysis of the effects of nonuniform sap velocity profiles on heat dissipation estimates showed that errors increased as v and the proportion of the probe in nonconducting wood increased. If half of a 20-mm probe is in sapwood with a v of 0.15 mm s(-1) and the other half is in nonconducting wood, then mean v for the whole probe can be underestimated by as much as 50%. A correction was developed that can be used if the proportion of the probe in nonconducting wood is known. Even with the entire heated probe in contact with conducting xylem, v would be underestimated when radial velocity gradients are present. In this case, the error would be smaller except when velocity gradients are very steep, as can occur in species with ring-porous wood anatomy. Errors occur because the relationship between DeltaT and v is nonlinear. Mean DeltaT along the probe is therefore not a measure of mean v, and users of heat dissipation probes should not assume that v is integrated along the length of the probe. The same type of error can occur when DeltaT is averaged through time while v is changing, but the error is small unless there are sudden, step changes between zero and high sap velocity. It is recommended that relatively short probes (20 mm or less) be used and that probes longer than the depth of conducting sapwood be avoided. Multiple probes inserted to a range of depths should be used in situations where steep gradients in v are expected. If these conditions are met, heat dissipation probes remain useful and widely applicable for measuring sap flow in woody stems.

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.

Partitioning of soil water among canopy trees in a seasonally dry tropical forest

Little is known about partitioning of soil water resources in species-rich, seasonally dry tropical forests. We assessed spatial and temporal patterns of soil water utilization in several canopy tree species on Barro Colorado Island, Panama, during the 1997 dry season. Stable hydrogen isotope composition (δD) of xylem and soil water, soil volumetric water content (θ_v), and sap flow were measured concurrently. Evaporative fractionation near the soil surface caused soil water δD to decrease from about -15‰ at 0.1 m to -50 to -55‰ at 1.2 m depth. Groundwater sampled at the sources of nearby springs during this period yielded an average δD value of -60‰. θ_v increased sharply and nearly linearly with depth to 0.7 m, then increased more slowly between 0.7 and 1.05 m. Based on xylem δD values, water uptake in some individual plants appeared to be restricted largely to the upper 20 cm of the soil profile where θ_v dropped below 20% during the dry season. In contrast, other individuals appeared to have access to water at depths greater than 1 m where θ_v remained above 45% throughout the dry season. The depths of water sources for trees with intermediate xylem δD values were less certain because variation in soil water δD between 20 and 70 cm was relatively small. Xylem water δD was also strongly dependent on tree size (diameter at breast height), with smaller trees appearing to preferentially tap deeper sources of soil water than larger trees. This relationship appeared to be species independent. Trees able to exploit progressively deeper sources of soil water during the dry season, as indicated by increasingly negative xylem δD values, were also able to maintain constant or even increase rates of water use. Seasonal courses of water use and soil water partitioning were associated with leaf phenology. Species with the smallest seasonal variability in leaf fall were also able to tap increasingly deep sources of soil water as the dry season progressed. Comparison of xylem, soil, and groundwater δD values thus pointed to spatial and temporal partitioning of water resources among several tropical forest canopy tree species during the dry season.

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.