Introduction
The muscular metaboreflex, whose activation regulates blood flow during isometric and aerobic exercise, is blunted in patients with heart failure (HF), and cardiac resynchronization ...therapy (CRT) may restore this regulatory reflex.
Objective
To evaluate metaboreflex responses after CRT.
Methods
Thirteen HF patients and 12 age‐matched healthy control subjects underwent the following evaluations (pre‐ and post‐CRT implantation in the patient group): (a) heart rate, blood pressure, and forearm blood flow measurements; (b) muscle sympathetic nerve activity (MSNA) evaluation; and (c) peak oxygen consumption (VO2peak). Examinations were performed at rest, during moderate isometric exercise (IE), and during forearm ischemia (metaboreflex activation). The primary outcome was the increment in MSNA during limb ischemia compared to the rest moment (ΔMSNA rest to metaboreflex activation).
Results
After CRT, rest MSNA decreased in the HF participants: 50.4 ± 9.2 bursts/min pre‐CRT vs 34.0 ± 14.4 bursts/min post‐CRT, P = .001, accompanied by an improvement in systolic blood pressure and in rate‐pressure product. MSNA during limb ischemia decreased: 56.6 ± 11.5 bursts/min pre‐CRT vs 43.6 ± 12.7 bursts/min post‐CRT, P = .001, and the ΔMSNA rest to metaboreflex activation increased: 0% (interquartile range IQR), −7 to 9) vs 13% (IQR, 5‐30), P = .03. An augmentation of mean blood pressure during limb ischemia post‐CRT was noticed: 94 mmHg (IQR, 81‐104) vs 110 mmHg (IQR, 100‐117), P = .04. CRT improved VO2peak, and this improvement was correlated with diminution in ΔMSNA pre‐ to post‐CRT at rest moment (rs = ‐0.74, P = .006).
Conclusion
CRT provides metaboreflex sensitization and MSNA enhancement. The restoration of sympathetic responsiveness correlates with the improvement in functional capacity.
Abstract
There are limited data on the effects of anthracyclines on right ventricular (RV) structure, function, and tissue characteristics. The goal of this study was to investigate the effects of ...anthracyclines on the RV using cardiac magnetic resonance (CMR). This was a post-hoc analysis of a prospective study of 27 breast cancer (BC) patients (51.8 ± 8.9 years) using CMR prior, and up to 3-times after anthracyclines (240 mg/m
2
) to measure RV volumes and mass, RV extracellular volume (ECV) and cardiomyocyte mass (CM). Before anthracyclines, LVEF (69.4 ± 3.6%) and RVEF (55.6 ± 9%) were normal. The median follow-up after anthracyclines was 399 days (IQR 310–517). The RVEF reached its nadir (46.3 ± 6.8%) after 9-months (
P
< 0.001). RV mass-index and RV CM decreased to 13 ± 2.8 g/m
2
and 8.13 ± 2 g/m
2
, respectively, at 16-months after anthracyclines. The RV ECV expanded from 0.26 ± 0.07 by 0.14 (53%) to 0.40 ± 0.1 (
P
< 0.001). The RV ECV expansion correlated with a decrease in RV mass-index (r = −0.46;
P
< 0.001) and the increase in CK-MB. An RV ESV index at baseline above its median predicted an increased risk of LV dysfunction post-anthracyclines. In BC patients treated with anthracyclines, RV atrophy, systolic dysfunction, and a parallel increase of diffuse interstitial fibrosis indicate a cardiotoxic response on a similar scale as previously seen in the systemic left ventricle.
Background 123 Iodine‐meta‐iodobenzylguanidine scintigraphy is useful for assessing cardiac autonomic dysfunction and predict outcomes in heart failure (HF). The relationship of cardiac sympathetic ...function with myocardial remodeling and diffuse fibrosis remains largely unknown. We aimed to evaluate the cardiac sympathetic function of patients with HF and its relation with myocardial remodeling and exercise capacity. Methods and Results Prospectively enrolled patients with HF (New York Heart Association class II–III) were stratified into HF with preserved left ventricular ejection fraction LVEF ≥45%) and reduced LVEF. Ventricular morphology/function and myocardial extracellular volume (ECV) fraction were quantified by cardiovascular magnetic resonance, global longitudinal strain by echocardiography, cardiac sympathetic function by heart‐to‐mediastinum ratio from 123 iodine‐meta‐iodobenzylguanidine scintigraphy. All participants underwent cardiopulmonary exercise testing. The cohort included 33 patients with HF with preserved LVEF (LVEF, 60±10%; NT‐proBNP N‐terminal pro‐B‐type natriuretic peptide, 248 interquartile range, 79–574 pg/dL), 28 with HF with reduced LVEF (LVEF, 30±9%; NT‐proBNP, 743 interquartile range, 250–2054 pg/dL) and 20 controls (LVEF, 65±5%; NT‐proBNP, 40 interquartile range, 19–50 pg/dL). Delayed (4 hours) 123 iodine‐meta‐iodobenzylguanidine heart‐to‐mediastinum ratio was lower in HF with preserved LVEF (1.59±0.25) and HF with reduced LVEF (1.45±0.16) versus controls (1.92±0.24; P <0.001), and correlated negatively with diffuse fibrosis assessed by ECV ( R =−0.34, P <0.01). ECV in segments without LGE was increased in HF with preserved ejection fraction (0.32±0.05%) and HF with reduced left ventricular ejection fraction (0.31±0.04%) versus controls (0.28±0.04, P <0.05) and was associated with the age‐ and sex‐adjusted maximum oxygen consumption (peak oxygen consumption); ( R =−0.41, P <0.01). Preliminary analysis indicates that cardiac sympathetic function might potentially act as a mediator in the association between ECV and NT‐proBNP levels. Conclusions Abnormally low cardiac sympathetic function in patients with HF with reduced and preserved LVEF is associated with extracellular volume expansion and decreased cardiopulmonary functional capacity.
Aims
Despite of recent advances in the pharmacological treatment, heart failure (HF) maintains significant morbidity and mortality rates. While serum potassium disorders are common and associated ...with adverse outcomes, the exact recommended potassium level for patients with HF are not entirely established. We aimed to investigate the prognostic role of potassium levels on a cohort of patients with symptomatic chronic HF.
Methods and results
Patients with symptomatic chronic HF were identified at the referral to 6 min walking test (6MWT) and were prospectively followed up for cardiovascular events. Clinical and laboratorial data were retrospectively obtained. The primary endpoint was the composite of cardiovascular death, hospitalization due to HF, and heart transplantation. The cohort included 178 patients with HF with the mean age of 51 ± 12.76 years, 39% were female, 85% of non‐ischaemic cardiomyopathy, and 38% had New York Heart Association Class III with a relatively high Meta‐Analysis Global Group in Chronic Heart Failure (MAGGIC) score (12.91 ± 6.6). The mean left ventricular ejection fraction was 39.98 ± 15.79%, and the mean 6MWT distance was 353 ± 136 m. After a median follow‐up of 516 days, there were 22 major cardiovascular events (4 cardiovascular deaths, 13 HF admissions, and 5 heart transplants). Patients were stratified according to cut‐point level of serum potassium of 4.7 mmol/L to predict combined cardiac events based on receiver operating characteristic analysis. Individuals with higher potassium levels had worse renal function (glomerular filtration rate, K ≤ 4.7: 102.8 ± 32.2 mL/min/1.73 m2 vs. K > 4.7: 85.42 ± 36.2 mL/min/1.73 m2, P = 0.004), higher proportion of New York Heart Association Class III patients (K ≤ 4.7: 28% vs. K > 4.7: 48%, P = 0.0029), and also higher MAGGIC score (K ≤ 4.7: 12.08 ± 5.7 vs. K > 4.7: 14.9 ± 7.9, P = 0.0089), without significant differences on the baseline pharmacological HF treatment. Both potassium levels hazard ratio (HR) 4.26, 95% confidence interval (CI) 1.59–11.421, P = 0.003 and 6MWT distance (HR 0.99, 95% CI 0.993–0.999, P = 0.01) were independently associated with the primary outcome. After adjustments for MAGGIC score and 6MWT distance, potassium levels > 4.7 mmol/L maintained a significant association with outcomes (HR 3.57, 95% CI 1.305–9.807, P = 0.013). Patients with K > 4.7 mmol/L were more likely to present clinical events during the follow‐up (log rank = 0.005). Adding potassium levels to the model including 6MWT and MAGGIC significantly improved the prediction of events over 2 years (integrated discrimination index 0.105, 95% CI 0.018–0.281, P = 0.012 and net reclassification index 0.447, 95% CI 0.077–0.703, P = 0.028).
Conclusions
Potassium levels were independently associated with worse outcomes in patients with chronic symptomatic HF, also improving the accuracy model for prognostic prediction when added to MAGGIC score and 6MWT distance. The potassium levels above 4.7 mmol/L might identify those patients at an increased risk of cardiovascular events.
Cardiomyocyte hypertrophy and interstitial fibrosis are key components of myocardial remodeling in Heart Failure (HF) with preserved (HFpEF) or reduced ejection fraction (HFrEF). MicroRNAs (miRNAs) ...are non-coding, evolutionarily conserved RNA molecules that may offer novel insights into myocardial remodeling. This study aimed to characterize miRNA expression in HFpEF (LVEF ≥ 45%) and HFrEF (LVEF < 45%) and its association with myocardial remodeling.
Prospectively enrolled symptomatic HF patients (HFpEF:n = 36; HFrEF:n = 31) and controls (n = 23) underwent cardiac magnetic resonance imaging with T1-mapping and circulating miRNA expression (OpenArray system).
13 of 188 miRNAs were differentially expressed between HF groups (11 downregulated in HFpEF). Myocardial extracellular volume (ECV) was increased in both HF groups (HFpEF 30 ± 5%; HFrEF 30 ± 3%; controls 26 ± 2%, p < 0.001). miR-128a-3p, linked to cardiac hypertrophy, fibrosis, and dysfunction, correlated positively with ECV in HFpEF (r = 0.60, p = 0.01) and negatively in HFrEF (r = −0.51, p = 0.04). miR-423-5p overexpression, previously associated HF mortality, was inversely associated with LVEF (r = − 0.29, p = 0.04) and intracellular water lifetime (τic) (r = −0.45, p < 0.05) in both HF groups, and with NT-proBNP in HFpEF (r = −0.63, p < 0.01).
miRNA expression profiles differed between HF phenotypes. The differential expression and association of miR-128a-3p with ECV may reflect the distinct vascular, interstitial, and cellular etiologies of HF phenotypes.
Introduction
Data on patients hospitalized with acute heart failure in Brazil scarce.
Methods
We performed a cross-sectional, retrospective, records-based study using data retrieved from a large ...public database of heart failure admissions to any hospital from the Brazilian National Public Health System (SUS) (SUS Hospital Information System SIHSUS registry) to determine the in-hospital all-cause mortality rate, in-hospital renal replacement therapy rate and its association with outcome.
Results
In total, 910,128 hospitalizations due to heart failure were identified in the SIHSUS registry between April 2017 and August 2021, of which 106,383 (11.7%) resulted in in-hospital death. Renal replacement therapy (required by 8,179 non-survivors 7.7% and 11,496 survivors 1.4%,
p
< 0.001) was associated with a 56% increase in the risk of death in the univariate regression model (HR 1.56, 95% CI 1.52 -1.59), a more than threefold increase of the duration of hospitalization, and a 45% or greater increase of cost per day. All forms of renal replacement therapy remained independently associated with in-hospital mortality in multivariable analysis (intermittent hemodialysis: HR 1.64, 95% CI 1.60 -1.69; continuous hemodialysis: HR 1.52, 95% CI 1.42 -1.63; peritoneal dialysis: HR 1.47, 95% CI 1.20 -1.88).
Discussion
The in-hospital mortality rate of 11.7% observed among patients with acute heart failure admitted to Brazilian public hospitals was alarmingly high, exceeding that of patients admitted to North American and European institutions. This is the first report to quantify the rate of renal replacement therapy in patients hospitalized with acute heart failure in Brazil.
Background:
Studies have shown significant benefits of exercise therapy in heart failure (HF) with a reduced ejection fraction (HFrEF) and HF with a preserved ejection fraction (HFpEF). The ...mechanisms responsible for the beneficial effect of exercise in HFrEF and HFpEF are still unclear. We hypothesized that the effect of exercise on myocardial remodeling may explain its beneficial effect.
Methods:
IMAGING-REHAB-HF is a single-center, randomized, controlled clinical trial using cardiac magnetic resonance imaging, vasomotor endothelial function, cardiac sympathetic activity imaging and serum biomarkers to compare the effect of exercise therapy in HFpEF (LVEF ≥ 45%) and HFrEF (LVEF < 45%). Subjects will be assessed at baseline and after 4 months. The exercise program will consist of three 60-min exercise sessions/week. The primary endpoints are the effect of exercise on myocardial extracellular volume (ECV), left ventricular (LV) systolic function, LV mass, LV mass-to-volume and LV cardiomyocyte volume. Secondary endpoints include the effect of exercise on vasomotor endothelial function, cardiac sympathetic activity and plasmatic biomarkers. Patients will be allocated in a 2:1 fashion to supervised exercise program or usual care. A total sample size of 90 patients, divided into two groups according to LVEF:HFpEF group (45 patients:30 in the intervention arm and 15 in the control arm) and HFrEF group (45 patients:30 in the intervention arm and 15 in the control arm) – will be necessary to achieve adequate power.
Conclusion:
This will be the first study to evaluate the benefits of a rehabilitation program on cardiac remodeling in HF patients. The unique design of our study may provide unique data to further elucidate the mechanisms involved in reverse cardiac remodeling after exercise in HFpEF and HFrEF patients.
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