No difference in postprandial mesenteric blood flow between healthy younger and elderly individuals.

We recently used phase-contrast magnetic resonance imaging (PC-MRI) to demonstrate an attenuated postprandial blood flow response in the superior mesenteric artery (SMA) in patients with Parkinson's disease compared to age- and sex-matched healthy controls. Since both groups showed substantial inter-individual variations, we extended the cohort of controls with a group of young individuals to investigate possible age-related effects. Seventeen healthy young subjects aged < 30 years and 17 elderly subjects aged > 50 years underwent serial PC-MRI to measure the postprandial blood flow response in the SMA after ingestion of a standardized liquid test meal (∼400 kcal). Postprandial blood flow dynamics in SMA did not differ between young and elderly subjects. A noticeable inter-individual variation in postprandial intestinal blood flow increase was found, and approximately 30% of the variation could be explained by the preprandial blood flow. Regardless of age, some subjects showed a remarkable transient SMA blood flow increase immediately after meal intake. This study provides tentative evidence that postprandial blood flow dynamics in SMA in healthy young and elderly subjects do not substantially differ, indicating that age is without impact on vascular response in SMA as an indicator for regulation of mesenteric perfusion in response to food intake.

The acute effects of furosemide in acute heart failure assessed by remote dielectric sensing. A protocol.

INTRODUCTION: Intravenous loop diuretics have been a key component in treating pulmonary oedema since the 1960s and have a Class 1 recommendation in the 2021 guidelines for acute heart failure (AHF). While the diuretic effect of loop diuretics is well established, it remains unclear how furosemide influences pulmonary congestion and cardiac filling pressures in the hyperacute phase before significant diuresis occurs. METHODS: This was a prospective study of adult patients with AHF and objective signs of pulmonary congestion admitted to the cardiac ward. Remote dielectric sensing (ReDS) will directly measure lung fluid content, and cardiac filling pressures will be assessed by echocardiography with Doppler and strain analysis. CONCLUSIONS: This study will examine if furosemide leads to a hyperacute reduction in pulmonary congestion assessed by ReDS independent of diuretic effects in patients with AHF. We hypothesise that the haemodynamic effect of furosemide shown on pulmonary congestion may explain the subjective instant relief in patients with AHF receiving furosemide. FUNDING: Dr. Grand's salary during this project is supported by a research grant from the Danish Cardiovascular Academy funded by Novo Nordisk Foundation grant number NNF20SA0067242 and by the Danish Heart Foundation. TRIAL REGISTRATION: This protocol was approved by the Scientific Ethical Committee, H-23029822, and the Danish Data Protection Agency P-2013-14703. The protocol was registered with ClinicalTrial.org on 29 August 2023 (Identifier: NCT06024889).

Combination of diuretics for acute heart failure: a protocol for a systematic review of randomised clinical trials with network meta-analysis and trial sequential analysis.

INTRODUCTION: Acute heart failure (AHF) is a critical, costly condition with high mortality rates, affecting millions annually. Despite advances in cardiovascular care, AHF treatment lacks robust evidence. AHF commonly manifests with sudden heart failure symptoms such as pulmonary congestion, and the pathophysiology involves fluid overload. Initial treatment is based on intravenous diuretics typically, but the optimal combination of drugs remains uncertain. METHODS AND ANALYSIS: We will systematically review randomised controlled trials enrolling patients with AHF and volume overload undergoing in-hospital diuretic treatment. We aim to investigate any diuretic intervention. Our search strategy includes the following databases: Embase, Medline, Latin American and Caribbean Health Sciences Literature, Web of Science and the Cochrane Central Register of Controlled Trials. The primary outcome is all-cause mortality. Secondary outcomes are serious adverse events, hospital readmission and kidney failure. Study results reported at the most extended follow-up will be used for all outcomes. If appropriate, we will conduct meta-analysis, trial sequential analysis and network meta-analysis. ETHICS AND DISSEMINATION: No ethics approval is required for this study. The results will be published in a peer-reviewed journal in this field. PROSPERO REGISTRATION NUMBER: CRD42023463979.

Vasodilators for Acute Heart Failure - A Systematic Review with Meta-Analysis.

BACKGROUND: Acute heart failure is a public health concern. This study systematically reviewed randomized clinical trials (RCTs) to evaluate vasodilators in acute heart failure. METHODS: The search was conducted across the databases of Medline, Embase, Latin American and the Caribbean Literature on Health Sciences, Web of Science, and the Cochrane Central Register of Controlled Trials. Inclusion criteria consisted of RCTs that compared vasodilators versus standard care, placebo, or cointerventions. The primary outcome was all-cause mortality; secondary outcomes were serious adverse events (SAEs), tracheal intubation, and length of hospital stay. Risk of bias was assessed in all trials. RESULTS: The study included 46 RCTs that enrolled 28,374 patients with acute heart failure. Vasodilators did not reduce the risk of all-cause mortality (risk ratio, 0.95; 95% confidence interval [CI], 0.87 to 1.04; I2=9.51%; P=0.26). No evidence of a difference was seen in the risk of SAEs (risk ratio, 1.01; 95% CI, 0.97 to 1.05; I2=0.94%) or length of hospital stay (mean difference, -0.10; 95% CI, -0.28 to 0.08; I2=69.84%). Vasodilator use was associated with a lower risk of tracheal intubation (risk ratio, 0.54; 95% CI, 0.30 to 0.99; I2=51.96%) compared with no receipt of vasodilators. CONCLUSIONS: In this systematic review with meta-analysis of patients with acute heart failure, vasodilators did not reduce all-cause mortality.

The importance of nonobstructive plaque characteristics in symptomatic and asymptomatic coronary artery disease.

BACKGROUND: We examined obstructive and nonobstructive plaque volumes in populations with subclinical and clinically manifested coronary artery disease (CAD) using quantitative computed tomography (QCT). METHODS: 855 participants with CAD (274 asymptomatic individuals, 254 acute chest pain patients without acute coronary syndrome (ACS), and 327 patients with ACS) underwent QCT of proximal coronary segments to assess participant-level plaque volumes of dense calcium, fibrous, fibrofatty, and necrotic core tissue. RESULTS: Nonobstructive (<50% stenosis) plaque volumes were greater than obstructive plaque volumes, irrespective of population (all p<0.0001): Asymptomatic individuals (mean (95% CI)): 218 [190-250] vs. 16 [12-22] mm3; acute chest pain patients without ACS: 300 [263-341] vs. 51 [41-62] mm3; patients with ACS: 370 [332-412] vs. 159 [139-182] mm3. After multivariable adjustment, nonobstructive fibrous and fibrofatty tissue volumes were greater in acute chest pain patients without ACS compared to asymptomatic individuals (fibrous tissue: 122 [107-139] vs. 175 [155-197] mm3, p<0.01; fibrofatty tissue: 44 [38-50] vs. 71 [63-80] mm3, p<0.01. Necrotic core tissue was greater in ACS patients (29 [26-33] mm3) compared to both asymptomatic individuals (15 [13-18] mm3, p<0.0001) and acute chest pain patients without ACS (21 [18-24] mm3, p<0.05). Nonobstructive dense calcium volumes did not differ between the three populations: 29 [24-36], 29 [23-35], and 41 [34-48] mm3, p>0.3 respectively. CONCLUSION: Nonobstructive CAD was the predominant contributor to total atherosclerotic plaque volume in both subclinical and clinically manifested CAD. Nonobstructive fibrous, fibrofatty and necrotic core tissue volumes increased with worsening clinical presentation, while nonobstructive dense calcium tissue volumes did not.