Automated grading of left ventricular segmental wall motion by an artificial neural network using color kinesis images

The present study describes an auxiliary tool in the diagnosis of left ventricular (LV) segmental wall motion (WM) abnormalities based on color-coded echocardiographic WM images. An artificial neural network (ANN) was developed and validated for grading LV segmental WM using data from color kinesis (CK) images, a technique developed to display the timing and magnitude of global and regional WM in real time. We evaluated 21 normal subjects and 20 patients with LVWM abnormalities revealed by two-dimensional echocardiography. CK images were obtained in two sets of viewing planes. A method was developed to analyze CK images, providing quantitation of fractional area change in each of the 16 LV segments. Two experienced observers analyzed LVWM from two-dimensional images and scored them as: 1) normal, 2) mild hypokinesia, 3) moderate hypokinesia, 4) severe hypokinesia, 5) akinesia, and 6) dyskinesia. Based on expert analysis of 10 normal subjects and 10 patients, we trained a multilayer perceptron ANN using a back-propagation algorithm to provide automated grading of LVWM, and this ANN was then tested in the remaining subjects. Excellent concordance between expert and ANN analysis was shown by ROC curve analysis, with measured area under the curve of 0.975. An excellent correlation was also obtained for global LV segmental WM index by expert and ANN analysis (R² = 0.99). In conclusion, ANN showed high accuracy for automated semi-quantitative grading of WM based on CK images. This technique can be an important aid, improving diagnostic accuracy and reducing inter-observer variability in scoring segmental LVWM.

Noninvasive prognostic markers for cardiac death and ventricular arrhythmia in long-term follow-up of subjects with chronic Chagas' disease

The objective of the present study was to investigate clinical, echocardiographic and electrocardiographic (12-lead resting ECG, 24-h ambulatory ECG monitoring and signal-averaged ECG (SAECG)) parameters in subjects with chronic Chagas' disease in a long-term follow-up as prognostic markers for adverse outcomes. Fifty adult outpatients (34 to 74 years old, 31 females) staged according to Los Andes class I, II or III and complaining of palpitation were enrolled in a longitudinal study. SAECG was analyzed in time and frequency domains and the endpoint was a composite of cardiac death and ventricular tachycardia. During a follow-up of 84.2 ± 39.0 months, 34.0% of the patients developed adverse outcomes (9 cardiac deaths and 11 episodes of ventricular tachycardia). After optimal dichotomization, in a stepwise multivariate Cox-hazard regression model, apical aneurysm (HR = 3.7; 95% CI = 1.2-1.3; P = 0.02), left ventricular ejection fraction <62% (HR = 4.60; 95% CI = 1.39-15.24; P = 0.01) and incidence of ventricular premature contractions >614 per 24 h (hazard ratio = 6.1; 95% CI = 1.7-22.6; P = 0.006) were independent predictors of the composite endpoint. Although a high frequency content in SAECG demonstrated association with the presence of left ventricular dysfunction and myocardial fibrosis, its predictive value for the composite endpoint was not significant. Apical aneurysms, reduced left ventricular function and a high incidence of ventricular ectopic beats over a 24-h period have a strong predictive value for a composite endpoint of cardiac death and ventricular tachycardia in subjects with chronic Chagas' disease.

Effect of exercise training and carvedilol treatment on cardiac function and structure in mice with sympathetic hyperactivity-induced heart failure

The present investigation was undertaken to study the effect of β-blockers and exercise training on cardiac structure and function, respectively, as well as overall functional capacity in a genetic model of sympathetic hyperactivity-induced heart failure in mice (α2A/α2CArKO). α2A/α2CArKO and their wild-type controls were studied for 2 months, from 3 to 5 months of age. Mice were randomly assigned to control (N = 45), carvedilol-treated (N = 29) or exercise-trained (N = 33) groups. Eight weeks of carvedilol treatment (38 mg/kg per day by gavage) or exercise training (swimming sessions of 60 min, 5 days/week) were performed. Exercise capacity was estimated using a graded treadmill protocol and HR was measured by tail cuff. Fractional shortening was evaluated by echocardiography. Cardiac structure and gastrocnemius capillary density were evaluated by light microscopy. At 3 months of age, no significant difference in fractional shortening or exercise capacity was observed between wild-type and α2A/α2CArKO mice. At 5 months of age, all α2A/α2CArKO mice displayed exercise intolerance and baseline tachycardia associated with reduced fractional shortening and gastrocnemius capillary rarefaction. In addition, α2A/ α2CArKO mice presented cardiac myocyte hypertrophy and ventricular fibrosis. Exercise training and carvedilol similarly improved fractional shortening in α2A/α2CArKO mice. The effect of exercise training was mainly associated with improved exercise tolerance and increased gastrocnemius capillary density while β-blocker therapy reduced cardiac myocyte dimension and ventricular collagen to wild-type control levels. Taken together, these data provide direct evidence for the respective beneficial effects of exercise training and carvedilol in α2A/α2CArKO mice preventing cardiac dysfunction. The different mechanisms associated with beneficial effects of exercise training and carvedilol suggest future studies associating both therapies.

Aerobic exercise training in heart failure: impact on sympathetic hyperactivity and cardiac and skeletal muscle function

Heart failure is a common endpoint for many forms of cardiovascular disease and a significant cause of morbidity and mortality. Chronic neurohumoral excitation (i.e., sympathetic hyperactivity) has been considered to be a hallmark of heart failure and is associated with a poor prognosis, cardiac dysfunction and remodeling, and skeletal myopathy. Aerobic exercise training is efficient in counteracting sympathetic hyperactivity and its toxic effects on cardiac and skeletal muscles. In this review, we describe the effects of aerobic exercise training on sympathetic hyperactivity, skeletal myopathy, as well as cardiac function and remodeling in human and animal heart failure. We also discuss the mechanisms underlying the effects of aerobic exercise training.

Muscarinic antibodies and heart rate responses to dynamic exercise and to the Valsalva maneuver in chronic chagasic patients

We have studied the cardiac chronotropic responses to the Valsalva maneuver and to dynamic exercise of twenty chronic chagasic patients with normal left ventricular function and no segmental wall abnormalities by two-dimensional echocardiogram. The absolute increase in heart rate of the patients (Δ = 21.5 ± 10 bpm, M±SD) during the maneuver was significantly diminished when compared to controls (Δ = 31.30 ± 70, M±SD, p = 0.03). The minimum heart rate (58.24 ± 8.90 vs. 62.80 ± 10, p = 0.68) and the absolute decrease in heart rate at the end of the maneuver (Δ = 38.30 ± 13 vs. Δ = 31.47 ± 17, p = 0.10) were not different from controls. The initial heart rate acceleration during dynamic exercise (Δ = 12 ± 7.55 vs. Δ = 19 ± 7.27, M±SD, p = 0.01) was also diminished, but the heart rate recovery during the first ten seconds was more prominent in the sero-positive patients (Median: 14, Interquartile range: (9.75-17.50 vs. 5(0-8.75, p = 0.001). The serum levels of muscarinic cardiac auto-antibodies were significantly higher in the chagasic patients (Median: 34.58, Interquartile Range: 17-46.5, Optical Density) than in controls (Median: 0, Interquartile Range: 0-22.25, p = 0.001) and correlated significantly and directly (r = 0.68, p = 0.002) with early heart rate recovery during dynamic exercise. The results of this investigation indirectly suggest that, the cardiac muscarinic auto-antibodies may have positive agonist effects on parasympathetic heart rate control of chagasic patients.

Cholinergic stimulation with pyridostigmine, hemodynamic and echocardiographic analysis in healthy subjects

OBJECTIVE: Growing evidence suggests that sudden death after an acute myocardial infarction (AMI) correlates with autonomic nervous system imbalance. Parasympathomimetic drugs have been tested to reverse these changes. However, their effects on ventricular function need specific evaluation. Our objective was to analyze pyridostigmine's (PYR) effect on hemodynamic and echocardiographic variables of ventricular function. METHODS: Twenty healthy volunteers underwent Doppler echocardiographic evaluations, blood pressure (BP), and heart rate (HR) assessment at rest, before and 120 min after ingestion of 30 mg PYR or placebo, according to a double-blind, placebo-controlled, crossed and randomized protocol, on different days. RESULTS: PYR was well tolerated and did not cause alterations in BP or in ventricular systolic function. A reduction in HR of 10.9±1.3% occurred (p<0,00001). There was an A wave reduction in the mitral flow (p<0.01) and an E/A ratio increase (p<0.001) without changes in the other diastolic function parameters (p>0.05). CONCLUSION: PYR reduces HR and increases E/A ratio, without hemodynamic impairment or ventricular function change.

Anomalous origin of the left coronary artery from the pulmonary trunk. Clinical features and midterm results after surgical treatment

OBJECTIVE: To report the authors' experience with the anomalous origin of the left coronary artery (AOLCA) from the pulmonary trunk, emphasizing preoperative data, surgical aspects and midterm results of the follow-up. METHODS: Retrospective analysis of 11 patients operated upon at the Royal Brompton Hospital from October, 84 to April, 97. RESULTS: Nine infants had heart failure (HF) and two other children presented with dyspnea and chest pain. All had ECG changes. The echocardiogram identified the anomalous origin of the coronary artery in 7 (64%) patients and hemodynamic studies were performed in 7 patients. All infants were operated upon between the 2nd and 10th month of life. Six patients were treated with aortic reimplantation of the left coronary artery, whereas five were operated upon according to the Takeuchi technique. All patients are alive, with clear improvement of the ECG changes and ventricular function, as evaluated by echocardiography. Two patients operated upon according to the Takeuchi technique required additional surgery due to severe supravalvular pulmonary stenosis. CONCLUSION: AOLCA is a rare disease. Most patients show early signs of severe HF associated with ECG findings. Surgical therapy must be instituted early in the disease, preferentially through aortic implantation of the anomalous coronary artery, with a high possibility of success. Shortly after surgery, clinical and ECG improvement, as well as normalization of left ventricular function, should be expected.

Doppler echocardiographic evaluation of HIV-positive patients in different stages of the disease

OBJETIVE: To evaluate by Doppler echocardiography (DE) early abnormalities of ventricular function in HIV-positive patients, as well as other cardiac abnormalities that can be detected by this method, with special emphasis on mitral valve flow. METHODS: 84 HIV- positive patients, 59 with CD4 cell count >500/mm³ (Group A) and 25 with CD4 cell count <500/mm³ (Group B), were analyzed. CD4 cells were counted and matched with structural data and systolic and diastolic function of the left ventricle (LV), as analyzed by DE. The results were compared with those obtained in 47 healthy individuals (Group C). RESULTS: 8% of patients in Group B had mild pericardial effusion; 31.5% showed decreased systolic function of the LV, and 12% had moderate mitral regurgitation. A wave velocity from the mitral inflow was different among the 3 groups, being higher in Group B, where the deceleration time of the E wave of the mitral inflow and the E/A ratio were significantly lower with a normal value of the isovolumic relaxation time (IVRT). CONCLUSION: HIV-positive patients with a CD4 cell count >500/mm³ had no abnormalities by DE. Patients with a more advanced infection (those with a CD4 cell count <500/mm³), had a significantly abnormal LV systolic function and a higher incidence of pericardial effusion and mitral regurgitation. Mitral valve inflow by Doppler did not indicate diastolic dysfunction.

Critical aortic stenosis in the neonate. Clinical assessment and surgical outcome in 18 patients

OBJECTIVE - To assess neonates with aortic stenosis with early decompensation operated upon. (LCO) (CHF). METHODS - A and retrospective study analyzing 6 neonates with LCO, group I (GI), and 12 neonates with CHF, group II (GII). Clinical radiographic, electrocardiographic and echocardiographic findings also provided comparative bases for the study, as did surgical and evolutional findings. RESULTS - The mean ages at hospitalization and surgery (p = 0.0031) were 14.3 and 14.8 days in GI and 35.4 and 42.8 days in GII, respectively. Cardiac murmurs were more intense in GII (p = 0.0220). The aortic ring was smaller in GI (8.0 ± 2.5mm) as compared to GII (11.4±1.4mm) (p = 0.2882). Ventricular function was reduced to 18±5.5% and 33.3±7.6% in GI and GII, respectively (p = 0.0162). Aortic atresia, however, was present only in 2 neonates in GI. Five of 6 patients in GI died but all patients in GII survived (p=0.0007). In the latter group, 84.6% of the patients were in functional class I (FC-I) in the long-term follow-up, with moderate residual lesions in 6 neonates, discrete residual lesions in 4, and reoperation in 2. CONCLUSION - Aortic stenosis is a severe anomaly of the neonate, whose immediate evolution depends on the pre-operative anatomic and functional findings, and the late evolution essentially depends on the anatomic features of the valve.

Treatment of persistent rejection with methotrexate in stable patients submitted to heart transplantation

OBJECTIVE:To evaluate the use of methotrexate for the treatment of recurrent rejection in heart transplant recipients. METHODS: We studied 6 patients submitted to heart transplantation that showed rejection grade > or = 3A (ISHLT) in two consecutives endomyocardial biopsy specimens. The dose was 11.26±3.75mg/week. The evaluated data were: ventricular function, endomyocardial biopsy, white cell count and number of rejection episodes before and after methotrexate administration. RESULTS: There was a reduction in the number of rejection episodes (5.17±1.47 before methotrexate; 2.33±1.75 after 6 months and 3.17±2.99 after 12 months of treatment, p=0.0193). The ventricular function was normal with ejection fraction of 76.5±4.80 before and 75.6±4.59 after methotrexate (p=0.4859). One patient did not finish the treatment because he showed signs of rejection associated with severe pericardial effusion. Five patients had a reduction in the white cell count (8,108±23.72 before and 5650±1350 after methotrexate, p=0.0961). One pulmonary infection with complete resolution after antibiotic treatment was observed. CONCLUSION: Methotrexate in low doses is an effective adjunct therapy in the treatment of recurrent rejection after heart transplantation.

Beta-adrenergic blocking agents in heart failure

Cardiac dysfunction in heart failure is widely recognized as a progressive process, regardless of the clinical signs and symptoms. An increase in cardiac sympathetic drive is one of the earliest neurohormonal responses occurring in patients with heart failure and may be one of the major causes of the progressive remodeling leading to the decline in myocardial function, and responsible for the poor prognosis of patients with heart failure. Therefore, recent data provided by several appropriately designed clinical trials clearly indicate the benefits of beta-adrenoceptor blocking agents, combined with diuretics, ACE inhibitors, and digoxin in chronic heart failure class II to IV due to systolic ventricular dysfunction. The benefits are related to symptoms, functional capacity, remodeling, and improvement in left ventricular function, reduction in cardiovascular hospitalization, a decrease in the overall and sudden cardiac death rate, and are similar in patients with ischemic or nonischemic cardiomyopathy, independent of age, gender, or functional class. In this review we describe the cardiovascular effects of the increase in sympathetic drive, the pharmacological properties of the beta-blockers most evaluated in heart failure therapy (metoprolol, bisoprolol, and carvedilol), the major clinical trials related to these agents in heart failure, the recommendations for their appropriate use in clinical practice, the precautions to be adopted, and how to handle the more common adverse reactions.

Pregnancy after cardiac transplantation. Report of one case and review

A 14-year-old female patient became pregnant 6 years after heart transplantation. The pregnancy evolved uneventfully, and the newborn infant was healthy. Five months after delivery, the mother was in good condition with preserved ventricular function, and the baby had normal neuro-psychomotor development. Even though the case reported here was a success, pregnancy following cardiac transplantation is considered a high-risk condition and remains contraindicated.

Pseudo-myocardial infarction during an episode of herpes zoster

The patient arrived at the emergency unit with a history of acute myocardial infarction, for which she was treated. Without improvement in the pain, the patient developed heart failure and underwent a hemodynamic study, which showed normal coronary arteries and extensive ventricular impairment. During evolution, the clinical findings improved and herpes zoster appeared on the right shoulder. In a few months the clinical findings subsided, and the findings of the electrocardiogram, chest X-ray, and ventricular function were normal. The patient is currently asymptomatic.

Noninvasive diagnosis of allograft vascular disease after heart transplantation

OBJECTIVE: To determine the predictive values of noninvasive tests for the detection of allograft vascular disease. METHODS: We studied 39 patients with mean ages of 48±13 years and a follow-up period of 86±13 months. The diagnosis of allograft vascular disease was made by cine-coronary arteriography, and it was considered as positive if lesions existed that caused > or = 50% obstruction of the lumen. Patients underwent 24h Holter monitoring, thallium scintigraphy, a treadmill stress test, and dobutamine stress echocardiography. Sensitivity, specificity, and positive and negative predictive values were determined in percentages for each method, as compared with the cine-coronary arteriography results. RESULTS: Allograft vascular disease was found in 15 (38%) patients. The Holter test showed 15.4% sensitivity, 95.5% specificity. For the treadmill stress test, sensitivity was 10%, specificity was 100%. When thallium scintigraphy was used, sensitivity was 40%, specificity 95.8%. On echocardiography with dobutamine, we found a 63.6% sensitivity, 91.3% specificity. When the dobutamine echocardiogram was associated with scintigraphy, sensitivity was 71.4%, specificity was 87%. CONCLUSION: In this group of patients, the combination of two noninvasive methods (dobutamine echocardiography and thallium scintigraphy) may be a good alternative for the detection of allograft vascular disease in asymptomatic patients with normal ventricular function.

The use of abciximab associated with primary angioplasty for treating acute myocardial infarction

OBJECTIVE: To assess the benefit resulting from the use of abciximab associated with primary angioplasty. The following parameters were analyzed in-hospital, at 30 days, and 6 months: (a) flow in the culprit artery; (b) ventricular function; (c) combined outcome of death, acute myocardial infarction, and aditional revascularization. METHODS: From November 1997 to June 1999, a longitudinal nonrandomized study with historical data of 137 patients with acute myocardial infarction within the first 12 hours. Patients undergoing primary angioplasty and were divided into 2 groups: those receiving (A) abciximab (26) or (B) conventional therapy (111). TIMI flow and regional ventricular function estimated by the standard deviation (SD)/chordis index were analyzed. RESULTS: At the end of angioplasty, TIMI 3 flow was observed in 76.9% and 83.8% of the patients in groups A and B, respectively (P=0.58). In the reevaluation, patients with TIMI flow <3 showed a 100% improvement in group A and a 33% in group B (P<0.0001). A significant improvement (P<0.0001) in regional ventricular function, by SD/chordis index, occurred in each group; no significant difference between groups however, was observed (29.9% x 20.2%; P=0.58). A nonsignificant reduction in the combined outcome in the in-hospital phase (3.85% A x 9.0% B; P=0.34) and on the 30th day (4.0% x 12.0%; P=0.22) was observed in group A. CONCLUSION: Abciximab improved blood flow. Primary angioplasty improved regional ventricular function independent of antithrombotic therapy. Abciximab showed a trend toward reducing the combined outcome in the in-hospital phase and on the 30th day.