Luciano Nastari

The effects of exercise training on sympathetic neural activation in advanced heart failure ☆: A randomized controlled trial

OBJECTIVES The goal of this study was to test the hypothesis that exercise training reduces resting sympathetic neural activation in patients with chronic advanced heart failure. BACKGROUND Exercise training in heart failure has been shown to be beneficial, but its mechanisms of benefit remain unknown. METHODS Sixteen New York Heart Association class II to III heart failure patients, age 35 to 60 years, ejection fraction < or =40% were divided into two groups: 1) exercise-trained (n = 7), and 2) sedentary control (n = 9). A normal control exercise-trained group was also studied (n = 8). The four-month supervised exercise training program consisted of three 60 min exercise sessions per week, at heart rate levels that corresponded up to 10% below the respiratory compensation point. Muscle sympathetic nerve activity (MSNA) was recorded directly from peroneal nerve using the technique of microneurography. Forearm blood flow was measured by venous plethysmography. RESULTS Baseline MSNA was greater in heart failure patients compared with normal controls; MSNA was uniformly decreased after exercise training in heart failure patients (60 +/- 3 vs. 38 +/- 3 bursts/100 heart beats), and the mean difference in the change was significantly (p < 0.05) greater than the mean difference in the change in sedentary heart failure or trained normal controls. In fact, resting MSNA in trained heart failure patients was no longer significantly greater than in trained normal controls. In heart failure patients, peak VO(2) and forearm blood flow, but not left ventricular ejection fraction, increased after training. CONCLUSIONS These findings demonstrate that exercise training in heart failure patients results in dramatic reductions in directly recorded resting sympathetic nerve activity. In fact, MSNA was no longer greater than in trained, healthy controls.

Ten-Year Incidence of Chagas Cardiomyopathy Among Asymptomatic Trypanosoma cruzi–Seropositive Former Blood Donors

Background— Very few studies have measured disease penetrance and prognostic factors of Chagas cardiomyopathy among asymptomatic Trypanosoma cruzi–infected persons. Methods and Results— We performed a retrospective cohort study among initially healthy blood donors with an index T cruzi–seropositive donation and age-, sex-, and period-matched seronegatives in 1996 to 2002 in the Brazilian cities of São Paulo and Montes Claros. In 2008 to 2010, all subjects underwent medical history, physical examination, ECGs, and echocardiograms. ECG and echocardiogram results were classified by blinded core laboratories, and records with abnormal results were reviewed by a blinded panel of 3 cardiologists who adjudicated the outcome of Chagas cardiomyopathy. Associations with Chagas cardiomyopathy were tested with multivariate logistic regression. Mean follow-up time between index donation and outcome assessment was 10.5 years for the seropositives and 11.1 years for the seronegatives. Among 499 T cruzi seropositives, 120 (24%) had definite Chagas cardiomyopathy, and among 488 T cruzi seronegatives, 24 (5%) had cardiomyopathy, for an incidence difference of 1.85 per 100 person-years attributable to T cruzi infection. Of the 120 seropositives classified as having Chagas cardiomyopathy, only 31 (26%) presented with ejection fraction <50%, and only 11 (9%) were classified as New York Heart Association class II or higher. Chagas cardiomyopathy was associated (P<0.01) with male sex, a history of abnormal ECG, and the presence of an S3 heart sound. Conclusions— There is a substantial annual incidence of Chagas cardiomyopathy among initially asymptomatic T cruzi–seropositive blood donors, although disease was mild at diagnosis.

Electrocardiographic Abnormalities in Trypanosoma cruzi Seropositive and Seronegative Former Blood Donors

Background Blood donor screening leads to large numbers of new diagnoses of Trypanosoma cruzi infection, with most donors in the asymptomatic chronic indeterminate form. Information on electrocardiogram (ECG) findings in infected blood donors is lacking and may help in counseling and recognizing those with more severe disease. Objectives To assess the frequency of ECG abnormalities in T.cruzi seropositive relative to seronegative blood donors, and to recognize ECG abnormalities associated with left ventricular dysfunction. Methods The study retrospectively enrolled 499 seropositive blood donors in São Paulo and Montes Claros, Brazil, and 483 seronegative control donors matched by site, gender, age, and year of blood donation. All subjects underwent a health clinical evaluation, ECG, and echocardiogram (Echo). ECG and Echo were reviewed blindly by centralized reading centers. Left ventricular (LV) dysfunction was defined as LV ejection fraction (EF)<0.50%. Results Right bundle branch block and left anterior fascicular block, isolated or in association, were more frequently found in seropositive cases (p<0.0001). Both QRS and QTc duration were associated with LVEF values (correlation coefficients −0.159,p<0.0003, and −0.142,p = 0.002) and showed a moderate accuracy in the detection of reduced LVEF (area under the ROC curve: 0.778 and 0.790, both p<0.0001). Several ECG abnormalities were more commonly found in seropositive donors with depressed LVEF, including rhythm disorders (frequent supraventricular ectopic beats, atrial fibrillation or flutter and pacemaker), intraventricular blocks (right bundle branch block and left anterior fascicular block) and ischemic abnormalities (possible old myocardial infarction and major and minor ST abnormalities). ECG was sensitive (92%) for recognition of seropositive donors with depressed LVEF and had a high negative predictive value (99%) for ruling out LV dysfunction. Conclusions ECG abnormalities are more frequent in seropositive than in seronegative blood donors. Several ECG abnormalities may help the recognition of seropositive cases with reduced LVEF who warrant careful follow-up and treatment.

Detection of Trypanosoma cruzi DNA in blood by PCR is associated with Chagas cardiomyopathy and disease severity

The significance of detection of Trypanosoma cruzi DNA in blood of antibody‐positive patients for risk of development of Chagas heart disease is not well established. The objective of this study was to compare detection of T. cruzi DNA with known clinical and laboratory markers of Chagas cardiomyopathy (CC) severity.

Relationship between outflow obstruction and left ventricular functional impairment in hypertrophic cardiomyopathy: a Doppler echocardiographic study.

Left ventricular outflow tract (LVOT) obstruction is predictive of a worse outcome in hypertrophic cardiomyopathy (HCM). In a detailed Doppler echocardiographic study of 178 selected HCM patients, the group of patients (n = 73) with the obstructive form (resting peak gradient ≥ 30 mmHg) presented more hypertrophy and poorer systolic and diastolic left ventricular (LV) functions than the HCM group (n = 105) without obstruction. LVOT peak gradient was positively correlated with hypertrophy (P < 0.0001) and negatively to tissue Doppler mitral annulus systolic (P = 0.0001) and early diastolic (P < 0.0001) velocities. The gradient significantly correlated with E/Ea ratio (r = 0.67; P < 0.0001). By multiple regression, LVOT gradient was related to E/Ea, LV maximal thickness and left atrial size. In comparison with patients without obstruction, patients with obstruction presented greater hypertrophy (P < 0.0001), lower systolic and early diastolic mitral annulus velocities (both P < 0.0001), higher E/Ea ratio (P < 0.0001) and higher global function index (P < 0.0001). In HCM, beyond the effects on hypertrophy, LVOT obstruction is an independent determinant of LV functional abnormalities.

Endothelial and Non-Endothelial Coronary Blood Flow Reserve and Left Ventricular Dysfunction in Systemic Hypertension

OBJECTIVES: We evaluated the impairment of endothelium-dependent and endothelium-independent coronary blood flow reserve after administration of intracoronary acetylcholine and adenosine, and its association with hypertensive cardiac disease. INTRODUCTION: Coronary blood flow reserve reduction has been proposed as a mechanism for the progression of compensated left ventricular hypertrophy to ventricular dysfunction. METHODS: Eighteen hypertensive patients with normal epicardial coronary arteries on angiography were divided into two groups according to left ventricular fractional shortening (FS). Group 1 (FS ≥0.25): n=8, FS=0.29 ± 0.03; Group 2 (FS <0.25): n=10, FS= 0.17 ± 0.03. RESULTS: Baseline coronary blood flow was similar in both groups (Group 1: 80.15 ± 26.41 mL/min, Group 2: 100.09 ± 21.51 mL/min, p=NS). In response to adenosine, coronary blood flow increased to 265.1 ± 100.2 mL/min in Group 1 and to 300.8 ± 113.6 mL/min (p <0.05) in Group 2. Endothelium-independent coronary blood flow reserve was similar in both groups (Group 1: 3.31 ± 0.68 and Group 2: 2.97 ± 0.80, p=NS). In response to acetylcholine, coronary blood flow increased to 156.08 ± 36.79 mL/min in Group 1 and to 177.8 ± 83.6 mL/min in Group 2 (p <0.05). Endothelium-dependent coronary blood flow reserve was similar in the two groups (Group 1: 2.08 ± 0.74 and group Group 2: 1.76 ± 0.61, p=NS). Peak acetylcholine/peak adenosine coronary blood flow response (Group 1: 0.65 ± 0.27 and Group 2: 0.60 ± 0.17) and minimal coronary vascular resistance (Group 1: 0.48 ± 0.21 mmHg/mL/min and Group 2: 0.34 ± 0.12 mmHg/mL/min) were similar in both groups (p= NS). Casual diastolic blood pressure and end-systolic left ventricular stress were independently associated with FS. CONCLUSIONS: In our hypertensive patients, endothelium-dependent and endothelium-independent coronary blood flow reserve vasodilator administrations had similar effects in patients with either normal or decreased left ventricular systolic function.

Tratamento de lesão de tronco da artéria coronária esquerda após radioterapia do tórax

Prevention of late cardiovascular complications after radiation therapy (RT) for treatment of a malignant tumor is challenging. We report the case of a young male patient with Hodgkins lymphoma treated with RT, who developed ischemic heart disease during follow-up, although he had no cardiovascular risk factors. We conclude that patients undergoing RT who experience chest pain should be fully investigated for coronary artery disease.

Does quantitative left ventricular regional wall motion change after fibrous tissue resection in endomyocardial fibrosis

OBJECTIVES: We compared left ventricular regional wall motion, the global left ventricular ejection fraction, and the New York Heart Association functional class pre- and postoperatively. INTRODUCTION: Endomyocardial fibrosis is characterized by fibrous tissue deposition in the endomyocardium of the apex and/or inflow tract of one or both ventricles. Although left ventricular global systolic function is preserved, patients exhibit wall motion abnormalities in the apical and inferoapical regions. Fibrous tissue resection in New York Heart Association FC III and IV endomyocardial fibrosis patients has been shown to decrease morbidity and mortality. METHODS: We prospectively studied 30 patients (20 female, 30±10 years) before and 5±8 months after surgery. The left ventricular ejection fraction was determined using the area-length method. Regional left ventricular motion was measured by the centerline method. Five left ventricular segments were analyzed pre- and postoperatively. Abnormality was expressed in units of standard deviation from the mean motion in a normal reference population. RESULTS: Left ventricular wall motion in the five regions did not differ between pre- and postoperative measurements. Additionally, the left ventricular ejection fraction did not change after surgery (0.45±0.13% x 0.43±0.12% pre- and postoperatively, respectively). The New York Heart Association functional class improved to class I in 40% and class II in 43% of patients postoperatively (p<0.05). CONCLUSIONS: Although endomyocardial fibrosis patients have improved clinical symptoms after surgery, the global left ventricular ejection fraction and regional wall motion in these patients do not change. This finding suggests that other explanations, such as improvements in diastolic function, may be operational.

Limitations in the Diagnosis of Noncompaction Cardiomyopathy by Echocardiography

Limitations in the Diagnosis of Noncompaction Cardiomyopathy by Echocardiography Viviane Tiemi Hotta,1,2 Sabrina Cunha Tendolo,2 Ana Clara Tude Rodrigues,3,4 Fábio Fernandes,2 Luciano Nastari,2 Charles Mady2 Instituto do Coração (InCor) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP);1 Fleury Medicina e Saúde;2 Hospital das Clínicas – FMUSP;3 Hospital Israelita Albert Einstein,4 São Paulo, SP – Brazil

Left Atrial Function in Patients with Chronic ChagasicCardiomyopathy

Background Chagas disease is a cause of dilated cardiomyopathy, and information about left atrial (LA) function in this disease still lacks. Objective To assess the different LA functions (reservoir, conduit and pump functions) and their correlation with the echocardiographic parameters of left ventricular (LV) systolic and diastolic functions. Methods 10 control subjects (CG), and patients with Chagas disease as follows: 26 with the indeterminate form (GI); 30 with ECG alterations (GII); and 19 with LV dysfunction (GIII). All patients underwent M-mode and two-dimensional echocardiography, pulsed-wave Doppler and tissue Doppler imaging. Results Reservoir function (Total Emptying Fraction: TEF): (p <0.0001), lower in GIII as compared to CG (p = 0.003), GI (p <0.001) and GII (p <0.001). Conduit function (Passive Emptying Fraction: PEF): (p = 0.004), lower in GIII (GIII and CG, p = 0.06; GI and GII, p = 0.06; and GII and GIII, p = 0.07). Pump function (Active Emptying Fraction: AEF): (p = 0.0001), lower in GIII as compared to CG (p = 0.05), GI (p<0.0001) and GII (p = 0.002). There was a negative correlation of E/e’average with the reservoir and pump functions (TEF and AEF), and a positive correlation of e’average with s’ wave (both septal and lateral walls) and the reservoir, conduit and pump LA functions. Conclusion An impairment of LA functions in Chagas cardiomyopathy was observed.