Mônica Quintão

Noninvasive ventilation with continuous positive airway pressure acutely improves 6-minute walk distance in chronic heart failure.

BACKGROUND Noninvasive ventilation with continuous positive airway pressure (CPAP) has been used in patients with chronic heart failure (CHF), although its effect on exercise tolerance in these patients is unknown. The aim of this study was to determine the effects of CPAP on exercise tolerance in outpatients with CHF. METHODS Following a double-blind, randomized, crossover, and placebo-controlled protocol, 12 patients with CHF (8 male; 4 female; age 54 ± 12 years; body mass index 27.3 ± 1.8 kg/m2, New York Heart Association Class II, III) underwent CPAP via nasal mask for 30 minutes in a recumbent position. Mask pressure was 3 cm H2O for 10 minutes, followed by individual progression up to 4 to 6 cm H2O, whereas placebo was fixed 0 to 1 cm H2O. A 6-minute walk test was performed after placebo and CPAP. RESULTS Continuous positive airway pressure decreased the resting heart rate (pre: 80 ± 17 bpm; post: 71 ± 15 bpm; P = .001) and mean arterial pressure (pre: 103 ± 14 mm Hg; post: 97 ± 13 mm Hg; P = .008). During exercise test, CPAP increased the distance covered (CPAP: 538 ± 78 m; placebo: 479 ± 83 m; P < .001) and the peak heart rate (CPAP: 98 ± 17; placebo: 89 ± 12 bpm; P = .049) but did not change the peak mean arterial pressure (P = .161). CONCLUSION Noninvasive ventilation with CPAP increased exercise tolerance in patients with stable CHF. Future clinical trials should investigate whether this effect is associated with improved clinical outcome.

Endothelial nitric oxide synthase Glu298Asp gene polymorphism in a multi-ethnical population with heart failure and controls.

Brazilian population has a multi-ethnical profile and the prevalence of endothelial nitric oxide synthase enzyme (eNOS) polymorphism in heart failure (HF) has not been previously studied. Therefore the present study assessed the association of eNOS Glu298Asp polymorphism in patients with HF and controls. In a crossover study, was analysed the distribution of the Glu298Asp in 100 outpatients with HF, and 103 healthy controls. Self-reported race were analyzed. Left atria and left ventricle diameters and ejection fraction were evaluated in patients group. Glu298Asp was analysed by polymerase chain reaction and restriction fragment length polymorphism. The patients average age was 59 years, 66% males, 49% Afro-descendants. The allelic frequency in patient group was Glu298=72%/Asp298=28% and the genotype frequency (GF) was Glu298Glu:49%; Glu298Asp:47%; Asp298Asp:4%. In control group, 60% Glu298 and 40% Asp298; 35% Glu298Glu, 49.5% Glu298Asp and 15.5% Asp298Asp. The prevalence of allele Glu298 was significantly higher in patients (p=0.009) as genotype Glu298Glu (p=0.03). The Glu298 in Afro-Brazilians (79%) and white patients (67%) were similar, although there was significant difference (p=0.03) in GF Glu298Glu between Afro-Brazilians and whites. There was an increased prevalence of hypertension and increased atria in Glu298Glu patients comparing with combined genotype Glu298Asp and Asp298Asp. This study suggests a regional variation in the distribution of Glu298Asp. The comparison of this distribution in African-Brazilian suggests a synergistic effect of African-descendent, Glu298Glu genotype and HF. Also demonstrated an increased frequency of Glu298 and Glu298Glu, suggesting interaction of them with HF. In HF patients, the clinical, echocardiograph and genotype analysis suggests an association of Glu298 allele and hypertension.

β-adrenergic receptor polymorphisms in susceptibility, response to treatment and prognosis in heart failure: Implication of ethnicity

Common functional polymorphisms in β-adrenergic receptor (βAR) genes have been associated with heart failure (HF) phenotypes and pharmacogenetic interactions with βAR blockers. This study evaluated the association between βAR polymorphisms and carvedilol drug response and prognosis in patients with HF. In this prospective cohort controlled study, 326 volunteers were enrolled [146 HF patients (ejection fraction (EF)<50% by Simpson) and 180 healthy controls]. Drug response was evaluated by echocardiography and outcomes were mortality and hospitalization. DNA was extracted from peripheral blood leukocytes, fragments were amplified by the polymerase reaction and genotyped by restriction fragment length polymorphism (RFLP) for Ser49Gly and Arg389Gly βAR-1 polymorphisms and Gln27Glu and Arg16Gly βAR-2 polymorphisms. The study population was in Hardy‑Weinberg equilibrium. The survival rate was adjusted using the Kaplan-Meier method. HF patients showed the following characteristics: EF 35±9%, 69.9% male, age 59±13 years, 50.7% self-identified as black, 46% had ischemic etiology. The mean follow-up of 23 months showed 18 mortalities and 46 hospitalizations. The genotypes Glu27Glu (24.7 vs. 6.1%, p=0.0004) and Arg16Arg (72.6 vs. 22.8, p<0.0001) of βAR2 polymorphisms and Gly49Gly (33.6 vs. 4.3%, p<0.0001) of the βAR1 polymorphism were higher in HF patients compared with controls. Patients with hospital admission showed a significantly higher Gly389 allelic frequency (54.9 vs. 42.1%, p=0.039), and the trend prevailed among patients who succumbed to the disease (61.1%, p=0.047). Black patients with the Ser49Ser genotype showed a reduced survival compared with the Gly49Gly or Ser49Gly genotypes (p=0.028). There was no association between improved LVEF >20% and βAR polymorphisms. HF patients with β-blocker therapy and the Gly389 allele have reduced event-free survival compared to those carrying the Arg389 allele. Additionally, systolic HF outpatients undergoing β-blocker therapy, self‑identified as black and homozygous for Ser49Ser may have reduced event-free survival, while Glu27Glu, Arg16Arg and Gly49Gly genotypes may be associated with risk for HF.

Efeito Agudo da Pressao Positiva Continua sobre a Pressao de Pulso na Insuficiencia Cardiaca Cronica

Background Patients with heart failure (HF) have left ventricular dysfunction and reduced mean arterial pressure (MAP). Increased adrenergic drive causes vasoconstriction and vessel resistance maintaining MAP, while increasing peripheral vascular resistance and conduit vessel stiffness. Increased pulse pressure (PP) reflects a complex interaction of the heart with the arterial and venous systems. Increased PP is an important risk marker in patients with chronic HF (CHF). Non-invasive ventilation (NIV) has been used for acute decompensated HF, to improve congestion and ventilation through both respiratory and hemodynamic effects. However, none of these studies have reported the effect of NIV on PP. Objective The objective of this study was to determine the acute effects of NIV with CPAP on PP in outpatients with CHF. Methods Following a double-blind, randomized, cross-over, and placebo-controlled protocol, twenty three patients with CHF (17 males; 60 ± 11 years; BMI 29 ± 5 kg/cm2, NYHA class II, III) underwent CPAP via nasal mask for 30 min in a recumbent position. Mask pressure was 6 cmH2O, whereas placebo was fixed at 0-1 cmH2O. PP and other non invasive hemodynamics variables were assessed before, during and after placebo and CPAP mode. Results CPAP decreased resting heart rate (Pre: 72 ± 9; vs. Post 5 min: 67 ± 10 bpm; p < 0.01) and MAP (CPAP: 87 ± 11; vs. control 96 ± 11 mmHg; p < 0.05 post 5 min). CPAP decreased PP (CPAP: 47 ± 20 pre to 38 ± 19 mmHg post; vs. control: 42 ± 12 mmHg, pre to 41 ± 18 post p < 0.05 post 5 min). Conclusion NIV with CPAP decreased pulse pressure in patients with stable CHF. Future clinical trials should investigate whether this effect is associated with improved clinical outcome.

Frequência Cardíaca de Recuperação no Primeiro Minuto no Teste de Caminhada de Seis Minutos em Pacientes com Insuficiência Cardíaca

Background Heart rate recovery at one minute of rest (HRR1) is a predictor of mortality in heart failure (HF), but its prognosis has not been assessed at six-minute walk test (6MWT) in these patients. Objective This study aimed to determine the HRR1 at 6MWT in patients with HF and its correlation with six-minute walk distance (6MWD). Methods Cross-sectional, controlled protocol with 161 individuals, 126 patients with stable systolic HF, allocated into 2 groups (G1 and G2) receiving or not β-blocker and 35 volunteers in control group (G3) had HRR1 recorded at the 6MWT. Results HRR1 and 6MWD were significantly different in the 3 groups. Mean values of HRR1 and 6MWD were: HRR1 = 12 ± 14 beat/min G1; 18 ± 16 beat/min G2 and 21 ± 13 beat/min G3; 6MWD = 423 ± 102 m G1; 396 ± 101m G2 and 484 ± 96 m G3 (p < 0.05). Results showed a correlation between HRR1 and 6MWD in G1(r = 0.3; p = 0.04) and in G3(r = 0.4; p= 0.03), but not in G2 (r= 0.12; p= 0.48). Conclusion HRR1 response was attenuated in patients using βB and showed correlation with 6MWD, reflecting better exercise tolerance. HRR1 after 6MWT seems to represent an alternative when treadmill tests could not be tolerated.

Fatigue: A Complex Symptom and its Impact on Cancer and Heart Failure

Mailing Address: Jacqueline Aparecida Borges Rua Martins Ferreira, 81/704. Postal Code: 22271-010, Botafogo, Rio de Janeiro, RJ Brazil. E-mail: jackborges@yahoo.com; jborges@inca.gov.br Fatigue: A Complex Symptom and its Impact on Cancer and Heart Failure Jacqueline Aparecida Borges, Mônica Maria Pena Quintão, Sergio S. M.C. Chermont, Hugo Tannus Furtado de Mendonça Filho, Evandro Tinoco Mesquita