GUILHERME VEIGA GUIMARAES
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Cardio-Pneumologia, Faculdade de Medicina
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/11 - Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação, Hospital das Clínicas, Faculdade de Medicina
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/11 - Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação, Hospital das Clínicas, Faculdade de Medicina
105 resultados
Resultados de Busca
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- Mode of Death on Chagas Heart Disease: Comparison with Other Etiologies. A Subanalysis of the REMADHE Prospective Trial(2013) AYUB-FERREIRA, Silvia M.; MANGINI, Sandrigo; ISSA, Victor S.; CRUZ, Fatima D.; BACAL, Fernando; GUIMARAES, Guilherme V.; CHIZZOLA, Paulo R.; CONCEICAO-SOUZA, Germano E.; MARCONDES-BRAGA, Fabiana G.; BOCCHI, Edimar A.Background: Sudden death has been considered the main cause of death in patients with Chagas heart disease. Nevertheless, this information comes from a period before the introduction of drugs that changed the natural history of heart failure. We sought to study the mode of death of patients with heart failure caused by Chagas heart disease, comparing with non-Chagas cardiomyopathy. Methods and results: We examined the REMADHE trial and grouped patients according to etiology (Chagas vs non-Chagas) and mode of death. The primary end-point was all-cause, heart failure and sudden death mortality; 342 patients were analyzed and 185 (54.1%) died. Death occurred in 56.4% Chagas patients and 53.7% non-Chagas patients. The cumulative incidence of all-cause mortality and heart failure mortality was significantly higher in Chagas patients compared to non-Chagas. There was no difference in the cumulative incidence of sudden death mortality between the two groups. In the Cox regression model, Chagas etiology (HR 2.76; CI 1.34-5.69; p = 0.006), LVEDD (left ventricular end diastolic diameter) (HR 1.07; CI 1.04-1.10; p<0.001), creatinine clearance (HR 0.98; CI 0.97-0.99; p = 0.006) and use of amiodarone (HR 3.05; CI 1.47-6.34; p = 0.003) were independently associated with heart failure mortality. LVEDD (HR 1.04; CI 1.01-1.07; p = 0.005) and use of beta-blocker (HR 0.52; CI 0.34-0.94; p = 0.014) were independently associated with sudden death mortality. Conclusions: In severe Chagas heart disease, progressive heart failure is the most important mode of death. These data challenge the current understanding of Chagas heart disease and may have implications in the selection of treatment choices, considering the mode of death.
- Prescribing and Regulating Exercise with RPE after Heart Transplant: A Pilot Study(2015) CIOLAC, Emmanuel Gomes; CASTRO, Rafael Ertner; GREVE, Julia Maria D'Andrea; BACAL, Fernando; BOCCHI, Edimar Alcides; GUIMARAES, Guilherme VeigaPurpose The objective of this study is to analyze the use of the 6-20 RPE scale for prescribing and self-regulating heated water-based exercise (HEx) and land-based exercise (LEx) in heart transplant recipients. Methods Fifteen (five females) clinically stable heart transplant recipients (time since surgery = 4.0 2.5 yr) age 46.7 11.8 yr underwent a symptom-limited maximal graded exercise test on a treadmill to determine their HR at anaerobic threshold (HRAT), respiratory compensation point (HRRCP), and maximal effort (HRmax). After a week, patients were randomized to perform 30 min of both HEx (walking inside the pool) and LEx (treadmill walking) sessions at a pace between 11 and 13 on the 6-20 RPE scale and had their HR measured every 4 min. The interval between sessions was 48-72 h. Results No significant differences between sessions were found in the average HR during HEx and LEx. Patients showed a delay in HR increase during both interventions, with the stabilization beginning after 8 min of exercise. Exercise HR was maintained between the HRAT and HRRCP (in the aerobic exercise training zone) for the most part of both HEx (72% of HR measurements) and LEx (66% of HR measurements). Only a few HR measurements stayed below HRAT (HEx = 9%, LEx = 13%) or above HRRCP (HEx = 19%, LEx = 21%) during both exercise sessions. Conclusion Exercise HR was maintained in the aerobic exercise training zone (between HRAT and HRRCP) for the most part of both sessions, suggesting that the 6-20 RPE scale may be an efficient tool for prescribing and self-regulating HEx and LEx in heart transplant recipients.
- Effects of short-term heated water-based exercise training on systemic blood pressure in patients with resistant hypertension: a pilot study(2013) GUIMARAES, Guilherme V.; CRUZ, Lais G. B.; TAVARES, Aline C.; DOREA, Egidio L.; FERNANDES-SILVA, Miguel M.; BOCCHI, Edimar A.High blood pressure (BP) increases the risk of cardiovascular diseases, and its control is a clinical challenge. Regular exercise lowers BP in patients with mild-to-moderate hypertension. No data are available on the effects of heated water-based exercise in hypertensive patients. Our objective was to evaluate the effects of heated water-based exercise on BP in patients with resistant hypertension. We tested the effects of 60-min heated water-based exercise training three times per week in 16 patients with resistant hypertension (age 55 +/- 6 years). The protocol included walking and callisthenic exercises. All patients underwent 24-h ambulatory blood pressure monitoring (ABPM) before and after a 2-week exercise program in a heated pool. Systolic office BP was reduced from 162 to 144 mmHg (P<0.004) after heated-water training. After the heated-water exercise training during 24-h ABPM, systolic BP decreased from 135 to 123 mmHg (P=0.02), diastolic BP decreased from 83 to 74 mmHg (P=0.001), daytime systolic BP decreased from 141 to 125 mmHg (P=0.02), diastolic BP decreased from 87 to 77 mmHg (P=0.009), night-time systolic BP decreased from 128 to 118 mmHg (P=0.06), and diastolic BP decreased from 77 to 69 mmHg (P=0.01). In addition, BP cardiovascular load was reduced significantly during the 24-h daytime and night-time period after the heated water-based exercise. Heated water-based exercise reduced office BP and 24-h daytime and night-time ABPM levels. These effects suggest that heated water-based exercise may have a potential as a new therapeutic approach to resistant hypertensive patients.
- Effects of the exercise training on skeletal muscle oxygen consumption in heart failure patients with reduced ejection fraction(2021) GUIMARAES, Guilherme Veiga; RIBEIRO, Fernando; CASTRO, Rafael Ertner; ROQUE, Jean Marcelo; MACHADO, Alexander Douglas Teixeira; ANTUNES-CORREA, Ligia M.; FERREIRA, Silvia Ayub; BOCCHI, Edimar AlcidesAims: Skeletal muscle dysfunction is a systemic consequence of heart failure (HF) that correlates with functional capacity. However, the impairment within the skeletal muscle is not well established. We investigated the effect of exercise training on peripheral muscular performance and oxygenation in HF patients. Methods and results: HF patients with ejection fraction <= 40% were randomized 2:1 to exercise training or control for 12 weeks. Muscle tissue oxygen was measured noninvasively by near-infrared spectroscopy (NIPS) during rest and a symptom-limited cardiopulmonary exercise test (CPET) before and after intervention. Measurements included skeletal muscle oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, total hemoglobin concentration, VO2 peak, VE/VCO2 slope, and heart rate. Muscle sympathetic nerve activity by microneurography, and muscle blood flow by plethysmography were also assessed at rest pre and post 12 weeks. Twenty-four participants (47.5 +/- 7.4 years, 58% men, 75% no ischemic) were allocated to exercise training (ET, n = 16) or control (CG, n = 8). At baseline, no differences between groups were found. Exercise improved VO2 peak, slope VE/VCO2, and heart rate. After the intervention, significant improvements at rest were seen in the ET group in muscle sympathetic nerve activity and muscle blood flow. Concomitantly, a significant decreased in Oxy-Hb (from 29.4 +/- 20.4 to 15.7 +/- 9.0 mu mol, p = 0.01), Deoxi-Hb (from 16.3 +/- 8.2 to 12.2 +/- 6.0 mu mol, p = 0.003) and HbT (from 45.7 +/- 27.6 to 27.7 +/- 13.4 mu mol, p = 0.008) was detected at peak exercise after training. No changes were observed in the control group. Conclusion: Exercise training improves skeletal muscle function and functional capacity in HF patients with reduced ejection fraction. This improvement was associated with increased oxygenation of the peripheral muscles, increased muscle blood flow, and decreased sympathetic nerve activity.
- Exercise Training Improves Chronotropic Incompetence but not Heart Rate Recovery to Exercise in Heart Transplant Patients(2015) CIOLAC, Emmanuel Gomes; CASTRO, Rafael E.; BACAL, Fernando; BOCCHI, Edimar A.; GUIMARAES, Guilherme V.
- Physical Exercise and MicroRNAs: New Frontiers in Heart Failure(2012) FERNANDES-SILVA, Miguel Morita; CARVALHO, Vagner Oliveira; GUIMARAES, Guilherme Veiga; BACAL, Fernando; BOCCHI, Edimar AlcidesAlthough the impact of exercise on survival of patients with heart failure has been recently questioned, exercise training improves quality of life, functional capacity, inflammation, endothelial and autonomic function. In recent years, interest has increased regarding a group of small non-protein coding RNAs called microRNAs. Studies have shown that the expression of these molecules changes in several pathological conditions, such as myocardial infarction, myocardial ischemia and heart failure, and when clinical improvement occurs, they seem to normalize. With the potential for practical applicability, markers that may be useful in diagnostic and prognostic assessment of heart failure have been identified, such as miR-423-5p. In addition, results of experimental studies have indicated that there are potential therapeutic effects of microRNAs. MicroRNAs are involved in the regulation of gene expression during fetal development and in adult individuals, increasing or decreasing in the heart in response to physiological stress, injury or hemodynamic overload. Thus, the study of the behavior of these molecules in physical exercise has brought important information about the effects of this therapeutic modality and represents a new era in the understanding of heart failure. This review aims to integrate the evidence on microRNAs in heart failure with greater relevance in the study of physical exercise.
- Hypertonic saline solution for prevention of renal dysfunction in patients with decompensated heart failure(2013) ISSA, Victor S.; ANDRADE, Lucia; AYUB-FERREIRA, Silvia M.; BACAL, Fernando; BRAGANCA, Ana C. de; GUIMARAES, Guilherme V.; MARCONDES-BRAGA, Fabiana G.; CRUZ, Fatima D.; CHIZZOLA, Paulo R.; CONCEICAO-SOUZA, Germano E.; VELASCO, Irineu T.; BOCCHI, Edimar A.Background: Renal dysfunction is associated with increased mortality in patients with decompensated heart failure. However, interventions targeted to prevention in this setting have been disappointing. We investigated the effects of hypertonic saline solution (HSS) for prevention of renal dysfunction in decompensated heart failure. Methods: In a double-blind randomized trial, patients with decompensated heart failure were assigned to receive three-day course of 100 mL HSS (NaCl 7.5%) twice daily or placebo. Primary end point was an increase in serumcreatinine of 0.3 mg/dL or more. Main secondary end point was change in biomarkers of renal function, including serum levels of creatinine, cystatin C, neutrophil gelatinase-associated lipocalin-NGAL and the urinary excretion of aquaporin 2 (AQP(2)), urea transporter (UT-A(1)), and sodium/hydrogen exchanger 3 (NHE3). Results: Twenty-two patients were assigned to HSS and 12 to placebo. Primary end point occurred in two (10%) patients in HSS group and six (50%) in placebo group (relative risk 0.3; 95% CI 0.09-0.98; P=0.01). Relative to baseline, serum creatinine and cystatin C levels were lower in HSS as compared to placebo (P=0.004 and 0.03, respectively). NGAL level was not statistically different between groups, however the urinary expression of AQP2, UT-A1 and NHE3 was significantly higher in HSS than in placebo. Conclusions: HSS administration attenuated heart failure-induced kidney dysfunction as indicated by improvement in both glomerular and tubular defects, a finding with important clinical implications. HSS modulated the expression of tubular proteins involved in regulation of water and electrolyte homeostasis.
- Heart rate response to exercise and cardiorespiratory fitness of young women at high familial risk for hypertension: effects of interval vs continuous training(2011) CIOLAC, Emmanuel G.; BOCCHI, Edimar A.; GREVE, Julia M. D.; GUIMARAES, Guilherme V.Exercise training is an effective intervention for treating and preventing hypertension, but its effects on heart rate (HR) response to exercise and cardiorespiratory fitness (CRF) of non-hypertensive offspring of hypertensive parents (FH+) has not been studied. We compared the effects of three times per week equal-volume high-intensity aerobic interval (AIT) and continuous moderate-intensity exercise (CME) on HR response to exercise and CRF of FH+. Forty-four young FH+ women (25.0 +/- 4.4 years) randomized to control (CON; n = 12), AIT (80-90% of VO2MAX; n = 16), or CME (50-60% of VO2MAX; n = 16) performed a graded exercise test (GXT) before and after 16 weeks of follow-up to evaluate HR response to exercise and several parameters of CRF. Resting, maximal, and reserve HR did not change after the follow-up in all groups. HR recovery (difference between HRMAX and HR at 1 minute of GXT recovery phase) improved only after AIT (11.8 +/- 4.9 vs. 20.6 +/- 5.8 bpm, p < 0.01). Both exercise programmes were effective for improving CRF parameters, but AIT was more effective than CME for improving oxygen consumption at the respiratory compensation point (VO2RCP; 22.1% vs. 8.8%, p = 0.008) and maximal effort (VO2MAX; 15.8% vs. 8.0%, p = 0.036), as well as tolerance time (TT) to reach anaerobic threshold (TTAT; 62.0 vs. 37.7, p = 0.048), TTRCP (49.3 vs. 32.9, p = 0.032), and TTMAX (38.9 vs. 29.2, p = 0.042). Exercise intensity was an important factor in improving HR recovery and CRF of FH+women. These findings may have important implications for designing exercise-training programmes for the prevention of an inherited hypertensive disorder.
conferenceObject Impact of optimizing of heart failure therapy in cardiac remodeling reversal: morphological, electrical and functional analysis(2013) SAMUEL, M. Avila; AYUB-FERREIRA, S. M.; ISSA, V. S.; VIEIRA, M. L. C.; GUIMARAES, G. V.; BELLI, J. F. C.; PEREIRA, M. B.; VALETTE, T. N.; BOCCHI, E. A.conferenceObject NEUROHUMORAL AND ENDOTHELIAL RESPONSES TO HEATED WATER-BASED EXERCISE IN RESISTANT HYPERTENSIVE PATIENTS THE NEUROHUMORAL AND ENDOTHELIAL RESPONSES TO THE BLOOD PRESSURE (BP) LOWER(2017) CRUZ, L. Galvani de Barros; SERAVALLE, G.; BOCCHI, E. A.; GRASSI, G.; GUIMARAES, G. V.