Rats with high left ventricular end-diastolic pressure can be identified by Doppler echocardiography one week after myocardial infarction

The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgically induced MI (N = 16) or sham-operation (N = 17) in female Wistar rats (200 to 250 g). The ratio of peak early (E) to late (A) diastolic LV filling velocities and the ratio of E velocity to peak early (Em) diastolic myocardial velocity were the best predictors of high LV end-diastolic pressure (>12 mmHg) soon after MI. Cut-off values of 1.77 for the E/A ratio (P = 0.001) identified rats with elevated LV end-diastolic pressure with 90 percent sensitivity and 80 percent specificity. Cut-off values of 20.4 for the E/Em ratio (P = 0.0001) identified rats with elevated LV end-diastolic pressure with 81.8 percent sensitivity and 80 percent specificity. Moreover, E/A and E/Em ratios were the only echocardiographic parameters independently associated with LV end-diastolic pressure in multiple linear regression analysis. Therefore, DE identifies rats with high LV end-diastolic pressure soon after MI. These findings have implications for using serial DE in animal selection and in the assessment of their response to experimental therapies.

Rats with high left ventricular end-diastolic pressure can be identified by Doppler echocardiography one week after myocardial infarction.

The severity of left ventricular (LV) dysfunction in rats with myocardial infarction (MI) varies widely. Because homogeneity in baseline parameters is essential for experimental investigations, a study was conducted to establish whether Doppler echocardiography (DE) could accurately identify animals with high LV end-diastolic pressure as a marker of LV dysfunction soon after MI. Direct measurements of LV end-diastolic pressure were made and DE was performed simultaneously 1 week after surgically induced MI (N = 16) or sham-operation (N = 17) in female Wistar rats (200 to 250 g). The ratio of peak early (E) to late (A) diastolic LV filling velocities and the ratio of E velocity to peak early (Em) diastolic myocardial velocity were the best predictors of high LV end-diastolic pressure (>12 mmHg) soon after MI. Cut-off values of 1.77 for the E/A ratio (P = 0.001) identified rats with elevated LV end-diastolic pressure with 90% sensitivity and 80% specificity. Cut-off values of 20.4 for the E/Em ratio (P = 0.0001) identified rats with elevated LV end-diastolic pressure with 81.8% sensitivity and 80% specificity. Moreover, E/A and E/Em ratios were the only echocardiographic parameters independently associated with LV end-diastolic pressure in multiple linear regression analysis. Therefore, DE identifies rats with high LV end-diastolic pressure soon after MI. These findings have implications for using serial DE in animal selection and in the assessment of their response to experimental therapies.

Performance of two-dimensional Doppler echocardiography for the assessment of infarct size and left ventricular function in rats.

Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6% when determined by histology and from 5 to 69.8% when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient). Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005). The fractional area change ranged from 28.5 +/- 5.6 (large-size myocardial infarction) to 53.1 +/- 1.5% (control) and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001) and histology (r = -0.78; P < 00001). The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 +/- 2.7) was significantly higher than for all others (control: 1.9 +/- 0.1; small-size myocardial infarction: 1.9 +/- 0.4; moderate-size myocardial infarction: 2.8 +/- 2.3). There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.

Performance of two-dimensional Doppler echocardiography for the assessment of infarct size and left ventricular function in rats

Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6 percent when determined by histology and from 5 to 69.8 percent when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient). Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005). The fractional area change ranged from 28.5 ± 5.6 (large-size myocardial infarction) to 53.1 ± 1.5 percent (control) and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001) and histology (r = -0.78; P < 00001). The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 ± 2.7) was significantly higher than for all others (control: 1.9 ± 0.1; small-size myocardial infarction: 1.9 ± 0.4; moderate-size myocardial infarction: 2.8 ± 2.3). There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.

Distribution of cardiac geometric patterns on echocardiography in essential hypertension. Impact of two criteria of stratification.

PURPOSE: To evaluate 2 left ventricular mass index (LVMI) normality criteria for the prevalence of left ventricular geometric patterns in a hypertensive population ( HT ). METHODS: 544 essential hypertensive patients, were evaluated by echocardiography, and different left ventricular hypertrophy criteria were applied: 1 - classic : men - 134 g/m2 and women - 110 g/m2; 2- obtained from the 95th percentil of LVMI from a normotensive population (NT). RESULTS: The prevalence of 4 left ventricular geometric patterns, respectively for criteria 1 and 2, were: normal geometry - 47.7% and 39.3%; concentric remodelying - 25.4% and 14.3%; concentric hypertrophy - 18.4% and 27.7% and excentric hypertrophy - 8.8% and 16.7%, which confered abnormal geometry to 52.6% and 60.7% of hypertensive. The comparative analysis between NT and normal geometry hypertensive group according to criteria 1, detected significative stuctural differences,"( *p < 0.05):LVMI- 78.4 +/- 1.50 vs 85.9 +/-0.95 g/m2 *; posterior wall thickness -8.5 +/- 0.1 vs 8.9 +/- 0.05 mm*; left atrium - 33.3 +/- 0.41 vs 34.7 +/- 0.30 mm *. With criteria 2, significative structural differences between the 2 groups were not observed. CONCLUSION: The use of a reference population based criteria, increased the abnormal left ventricular geometry prevalence in hypertensive patients and seemed more appropriate for left ventricular hypertrophy detection and risk stratification.

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.

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.

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.

Influence of autonomic neuropathy upon left ventricular dysfunction in insulin-dependent diabetic patients.

BACKGROUND: Diabetic cardiomyopathy is a well-defined complication of diabetes that occurs in the absence of ischemic, vascular, and hypertensive disease. HYPOTHESIS: The study was undertaken to test the relationship among autonomic neuropathy (AN), 24-h blood pressure (BP) profile, and left ventricular function. METHODS: Nineteen type-1 diabetic patients underwent autonomic tests and echocardiographic examination. Patients were divided according to the presence (AN+) or absence (AN-) of AN. RESULTS: In the AN+ group (n = 8), the E/A ratio at echo was lower than in the AN- group (n = 11) (1.1 +/- 0.3 vs. 1.6 +/- 0.3; p < 0.005). Systolic and diastolic BP reductions during sleep were smaller in the AN+ than in the AN- group (6.6 +/- 6.6 vs. 13.0 +/- 4.3%; p < 0.03 for systolic and 12.8 +/- 6.8 vs. 20.0 +/- 4.0% for diastolic BP reduction; p < 0.03, respectively). Considering all patients, the E/A ratio correlated inversely with awake diastolic BP (r - 0.63; p = 0.005); sleep systolic BP (r - 0.48; p = 0.04), and sleep diastolic BP (r - 0.67; p = 0.002). The AN correlated with diastolic interventricular septum thickness (r 0.57; p = 0.01), sleep systolic BP (r 0.45; p = 0.05), sleep diastolic BP (r 0.54; p = 0.02), and correlated inversely with systolic and diastolic sleep BP reduction (r - 0.49; p = 0.03 and r - 0.67; p = 0.002, respectively). Finally, E/A ratio and AN score correlated between themselves (r - 0.6; p = 0.005). CONCLUSION: Our results suggest that left ventricular diastolic dysfunction may be detected very early in type-1 diabetic patients with AN. Parasympathetic lesion and nocturnal elevations in BP could be the link between AN and diastolic ventricular dysfunction.

[Right ventricle-dependent coronary circulation in pulmonary atresia with intact ventricular septum. Absence of origin of the coronary arteries from the aorta]. / Circulação coronária dependente do ventrículo direito na atresia pulmonar com septo interventricular íntegro. Ausência da origem das artérias coronárias da 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)]. / Origem Anômala da artéria pulmonar direita em aorta ascendente (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.

Origem anômala da artéria pulmonar direita em aorta ascendente (hemitruncus) / Anomalous origin of right pulmonary artery from ascending aorta (hemitruncus)

A origem da artéria pulmonar direita em aorta ascendente é uma anomalia congênita rara, com poucos casos descritos na literatura. Descrevemos dois casos desta malforamçäo, um associado à interrupçäo de arco aórtico tipo B. Em ambos, o diagnóstico foi realizado mediante ecocardigrafia bidimensional, com confirmaçäo angiográfica em um. A origem da artéria pulmonar direita era próxima à valva aórtica, anomalia patogeneticamente diferente da origem perto da artéria inominada.

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.

[Quantification of mitral prosthesis failure by different methods of evaluation by transesophageal echocardiography]. / Quantificação de insuficiência protética mitral por diferentes métodos de avaliação pela ecocardiografia transesofágica.

PURPOSE: To evaluate the different methods for grading mitral regurgitation (MR) by transesophageal echocardiography (TEE) in patients with clinical suspicion of mitral prosthesis dysfunction. METHODS: Cardiac catheterization (Cath) was performed in 15 patients for grading the severity of prosthetic MR, divided in two groups based on the presence or absence of severe MR. Prosthetic MR was quantified by TEE using methods commonly used for MR of native valves: subjective assessment by color Doppler, objective assessment based on absolute jet area and on its relative area (jet area/left atrial area) and assessment based on the presence of systolic flow reversal in pulmonary vein. RESULTS: Prosthetic MR was mostly transprosthetic (14 patients) and eccentric (11 patients). There was significant correlation (p < 0.05) between Cath and TEE for identification of severe MR based on subjective assessment and on the presence of systolic flow reversal in pulmonary vein. Identification based on absolute (jet area > 7 cm2) and relative (jet area > 35% of left atrial area) jet areas did not reveal significant correlation with the angiographic grade and showed clear underestimation by TEE when the last method was used. However, there was good correlation (p < 0.05) if relative jet areas > 30% were considered as cut point. CONCLUSION: TEE correctly identified angiographic severe mitral prosthesis regurgitation, mainly by the presence of systolic flow reversal in pulmonary vein and subjective assessment. The estimation of severity of the prosthetic MR by absolute or relative jet area seems to be limited and should be used with caution due to eccentricity of the regurgitant jet, frequently seen in mitral prosthesis dysfunction.

Persistência do canal arterial e endarterite da artéria pulmonar / Patent ductus arteriosus and pulmonary artery endarteritis

Descrevemos uma paciente de sete anos com diagnóstico ecocardiográfico e confirmação cirúrgica de endarterite de artéria pulmonar, citada como complicação da persistência do canal arterial e ilustramos a necessidade de ressecção cirúrgica completa do processo infeccioso para evitar outras complicaçöes, como embolia pulmonar.

[Patent ductus arteriosus and pulmonary artery endarteritis]. / Persistência do canal arterial e endarterite da artéria pulmonar.

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.

Serum insulin levels, 24-hour blood pressure profile, and left ventricular mass in nonobese hypertensive patients.

In essential hypertensive patients, considered to be insulin-resistant, a blunted decline in nocturnal blood pressure is associated with increased adrenergic tone and left ventricular mass. Since insulin stimulates the sympathetic system, we tested whether insulin resistance and insulinemia influence left ventricular mass and the 24-hour blood pressure profile. We studied 29 nonobese hypertensive patients with office diastolic pressure between 95 and 110 mm Hg and normal oral glucose tolerance test after a 4-month washout period. They were then assigned to M-mode echocardiographic evaluation and 24-hour ambulatory blood pressure monitoring. The glucose and insulin responses to a 75-g oral glucose load were compared with those obtained in 16 weight-matched normotensive control subjects. During the oral glucose tolerance test the hypertensive patients compared with control subjects presented higher levels of glucose at 60 minutes (138.7 +/- 30.3 versus 108.7 +/- 35.7 mg/dL; P < .05) and 90 minutes (114.0 +/- 23.8 versus 94.8 +/- 31.1 mg/dL; P < .05) and insulin at 60 minutes (287.1 +/- 259.4 versus 142.1 +/- 83.9 pmol/L; P < .05). However, peak insulin levels after glucose load did not correlate with ambulatory blood pressure values or left ventricular mass index. Left ventricular mass index showed significant correlation with mean sleeping systolic pressure (rs = 56, P < .05) and diurnal systolic pressure (rs = .37, P < .05) but not with mean diurnal or sleeping diastolic pressures. In conclusion, our results indicate that in nonobese hypertensive patients, insulin resistance does not have any influence on the 24-hour blood pressure profile or on left ventricular mass index.(ABSTRACT TRUNCATED AT 250 WORDS)