ANA MARIA FONSECA WANDERLEY BRAGA

Índice h a partir de 2011
6
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico

Filtros

Limpar filtros

Configurações

search.filters.applied.f.dateIssued: 2021 ×

Resultados de Busca

Agora exibindo 1 - 2 de 2
  • article
    Exaggerated Exercise Blood Pressure as a Marker of Baroreflex Dysfunction in Normotensive Metabolic Syndrome Patients
    (2021) DUTRA-MARQUES, Akothirene C.; RODRIGUES, Sara; CEPEDA, Felipe X.; TOSCHI-DIAS, Edgar; RONDON, Eduardo; CARVALHO, Jefferson C.; ALVES, Maria Janieire N. N.; BRAGA, Ana Maria F. W.; RONDON, Maria Urbana P. B.; TROMBETTA, Ivani C.
    Introduction Exaggerated blood pressure response to exercise (EEBP = SBP >= 190 mmHg for women and >= 210 mmHg for men) during cardiopulmonary exercise test (CPET) is a predictor of cardiovascular risk. Sympathetic hyperactivation and decreased baroreflex sensitivity (BRS) seem to be involved in the progression of metabolic syndrome (MetS) to cardiovascular disease. Objective To test the hypotheses: (1) MetS patients within normal clinical blood pressure (BP) may present EEBP response to maximal exercise and (2) increased muscle sympathetic nerve activity (MSNA) and reduced BRS are associated with this impairment. Methods We selected MetS (ATP III) patients with normal BP (MetS_NT, n = 27, 59.3% males, 46.1 +/- 7.2 years) and a control group without MetS (C, n = 19, 48.4 +/- 7.4 years). We evaluated BRS for increases (BRS+) and decreases (BRS-) in spontaneous BP and HR fluctuations, MSNA (microneurography), BP from ambulatory blood pressure monitoring (ABPM), and auscultatory BP during CPET. Results Normotensive MetS (MetS_NT) had higher body mass index and impairment in all MetS risk factors when compared to the C group. MetS_NT had higher peak systolic BP (SBP) (195 +/- 17 vs. 177 +/- 24 mmHg, P = 0.007) and diastolic BP (91 +/- 11 vs. 79 +/- 10 mmHg, P = 0.001) during CPET than C. Additionally, we found that MetS patients with normal BP had lower spontaneous BRS- (9.6 +/- 3.3 vs. 12.2 +/- 4.9 ms/mmHg, P = 0.044) and higher levels of MSNA (29 +/- 6 vs. 18 +/- 4 bursts/min, P < 0.001) compared to C. Interestingly, 10 out of 27 MetS_NT (37%) showed EEBP (MetS_NT+), whereas 2 out of 19 C (10.5%) presented (P = 0.044). The subgroup of MetS_NT with EEBP (MetS_NT+, n = 10) had similar MSNA (P = 0.437), but lower BRS+ (P = 0.039) and BRS- (P = 0.039) compared with the subgroup without EEBP (MetS_NT-, n = 17). Either office BP or BP from ABPM was similar between subgroups MetS_NT+ and MetS_NT-, regardless of EEBP response. In the MetS_NT+ subgroup, there was an association of peak SBP with BRS- (R = -0.70; P = 0.02), triglycerides with peak SBP during CPET (R = 0.66; P = 0.039), and of triglycerides with BRS- (R = 0.71; P = 0.022). Conclusion Normotensive MetS patients already presented higher peak systolic and diastolic BP during maximal exercise, in addition to sympathetic hyperactivation and decreased baroreflex sensitivity. The EEBP in MetS_NT with apparent well-controlled BP may indicate a potential depressed neural baroreflex function, predisposing these patients to increased cardiovascular risk.
  • article 1 Citação(ões) na Scopus
    Oscillatory Pattern of Sympathetic Nerve Bursts Is Associated With Baroreflex Function in Heart Failure Patients With Reduced Ejection Fraction
    (2021) TOSCHI-DIAS, Edgar; MONTANO, Nicola; TOBALDINI, Eleonora; TREVIZAN, Patricia F.; V, Raphaela Groehs; ANTUNES-CORREA, Ligia M.; NOBRE, Thais S.; LOBO, Denise M.; SALES, Allan R. K.; UENO-PARDI, Linda M.; MATOS, Luciana D. N. J. de; OLIVEIRA, Patricia A.; BRAGA, Ana Maria F. W.; ALVES, Maria Janieire N. N.; NEGRAO, Carlos E.; RONDON, Maria Urbana P. B.
    Sympathetic hyperactivation and baroreflex dysfunction are hallmarks of heart failure with reduced ejection fraction (HFrEF). However, it is unknown whether the progressive loss of phasic activity of sympathetic nerve bursts is associated with baroreflex dysfunction in HFrEF patients. Therefore, we investigated the association between the oscillatory pattern of muscle sympathetic nerve activity (LFMSNA/HFMSNA) and the gain and coupling of the sympathetic baroreflex function in HFrEF patients. In a sample of 139 HFrEF patients, two groups were selected according to the level of LFMSNA/HFMSNA index: (1) Lower LFMSNA/HFMSNA (lower terciles, n = 46, aged 53 +/- 1 y) and (2) Higher LFMSNA/HFMSNA (upper terciles, n = 47, aged 52 +/- 2 y). Heart rate (ECG), arterial pressure (oscillometric method), and muscle sympathetic nerve activity (microneurography) were recorded for 10 min in patients while resting. Spectral analysis of muscle sympathetic nerve activity was conducted to assess the LFMSNA/HFMSNA, and cross-spectral analysis between diastolic arterial pressure, and muscle sympathetic nerve activity was conducted to assess the sympathetic baroreflex function. HFrEF patients with lower LFMSNA/HFMSNA had reduced left ventricular ejection fraction (26 +/- 1 vs. 29 +/- 1%, P = 0.03), gain (0.15 +/- 0.03 vs. 0.30 +/- 0.04 a.u./mmHg, P < 0.001) and coupling of sympathetic baroreflex function (0.26 +/- 0.03 vs. 0.56 +/- 0.04%, P < 0.001) and increased muscle sympathetic nerve activity (48 +/- 2 vs. 41 +/- 2 bursts/min, P < 0.01) and heart rate (71 +/- 2 vs. 61 & PLUSMN; 2 bpm, P < 0.001) compared with HFrEF patients with higher LFMSNA/HFMSNA. Further analysis showed an association between the LFMSNA/HFMSNA with coupling of sympathetic baroreflex function (R = 0.56, P < 0.001) and left ventricular ejection fraction (R = 0.23, P = 0.02). In conclusion, there is a direct association between LFMSNA/HFMSNA and sympathetic baroreflex function and muscle sympathetic nerve activity in HFrEF patients. This finding has clinical implications, because left ventricular ejection fraction is less in the HFrEF patients with lower LFMSNA/HFMSNA.