Serum insulin concentrations, insulin sensitivity, and endothelial function in essential hypertension and non-insulin-dependent diabetes mellitus

A series of studies is described in which specific and conventional insulin immunoassays, the hyperinsulinaemic clamp technique and forearm venous occlusion plethysmography with local intra-arterial infusions have been used to investigate: the effect of insulin assay specificity on the relationships among serum insulin concentrations, insulin sensitivity, and blood pressure in diabetic and non-diabetic subjects with and without essential hypertension (Chapter 5) the effect of sustained physiological activation of the renin-angiotensin system induced by moderate dietary sodium restriction on insulin sensitivity in patients with non-insulin-dependent diabetes mellitus (Chapter 6) the relationship between endothelial function and insulin sensitivity in healthy subjects (Chapter 7) Prior to these investigations, preliminary studies (Chapters 3 and 4) were performed in order to validate aspects of the clinical physiological techniques required for the measurement of blood flow and insulin sensitivity. The reproducibility of bilateral forearm venous occlusion plethysmography Studies using this technique to measure changes in forearm blood flow (FBF) during intra-arterial infusions of vasoactive substances often report changes in blood flow ratio (expressing responses in the intervention arm as a ratio of responses in the control arm) rather than absolute values for flow. However, unilateral measurements are reported by other investigators, and the possibility was considered that the method used for expressing responses might influence the conclusions reached. A reproducibility study was performed (Chapter 3) which demonstrated that the between-day intra-subject variability of bilateral forearm venous occlusion plethysmography (FBF ratios) was less than that of unilateral FBF measurements. The bilateral technique was used thereafter where possible

Association is not causation: treatment effects cannot be estimated from observational data in heart failure

Aims: Treatment ‘effects’ are often inferred from non-randomized and observational studies. These studies have inherent biases and limitations, which may make therapeutic inferences based on their results unreliable. We compared the conflicting findings of these studies to those of prospective randomized controlled trials (RCTs) in relation to pharmacological treatments for heart failure (HF). Methods and results: We searched Medline and Embase to identify studies of the association between non-randomized drug therapy and all-cause mortality in patients with HF until 31 December 2017. The treatments of interest were: angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, mineralocorticoid receptor antagonists (MRAs), statins, and digoxin. We compared the findings of these observational studies with those of relevant RCTs. We identified 92 publications, reporting 94 non-randomized studies, describing 158 estimates of the ‘effect’ of the six treatments of interest on all-cause mortality, i.e. some studies examined more than one treatment and/or HF phenotype. These six treatments had been tested in 25 RCTs. For example, two pivotal RCTs showed that MRAs reduced mortality in patients with HF with reduced ejection fraction. However, only one of 12 non-randomized studies found that MRAs were of benefit, with 10 finding a neutral effect, and one a harmful effect. Conclusion: This comprehensive comparison of studies of non-randomized data with the findings of RCTs in HF shows that it is not possible to make reliable therapeutic inferences from observational associations. While trials undoubtedly leave gaps in evidence and enrol selected participants, they clearly remain the best guide to the treatment of patients

Redefining heart failure phenotypes based on ejection fraction

No abstract available

Talking to patients with heart failure about end of life

No abstract available

Palliative care needs in patients hospitalized with heart failure (PCHF) study: rationale and design

Abstract Aims The primary aim of this study is to provide data to inform the design of a randomized controlled clinical trial (RCT) of a palliative care (PC) intervention in heart failure (HF). We will identify an appropriate study population with a high prevalence of PC needs defined using quantifiable measures. We will also identify which components a specific and targeted PC intervention in HF should include and attempt to define the most relevant trial outcomes. Methods An unselected, prospective, near-consecutive, cohort of patients admitted to hospital with acute decompensated HF will be enrolled over a 2-year period. All potential participants will be screened using B-type natriuretic peptide and echocardiography, and all those enrolled will be extensively characterized in terms of their HF status, comorbidity, and PC needs. Quantitative assessment of PC needs will include evaluation of general and disease-specific quality of life, mood, symptom burden, caregiver burden, and end of life care. Inpatient assessments will be performed and after discharge outpatient assessments will be carried out every 4 months for up to 2.5 years. Participants will be followed up for a minimum of 1 year for hospital admissions, and place and cause of death. Methods for identifying patients with HF with PC needs will be evaluated, and estimates of healthcare utilisation performed. Conclusion By assessing the prevalence of these needs, describing how these needs change over time, and evaluating how best PC needs can be identified, we will provide the foundation for designing an RCT of a PC intervention in HF

Reporting of lost to follow-up and treatment discontinuation in device and pharmacotherapy trials in chronic heart failure: a systematic review

Background—Premature treatment discontinuation and loss to follow-up (LTFU) with unknown outcomes leave uncertainty about the true efficacy and safety of a treatment and a lack of confidence in the results of any trial. We reviewed the extent of (and trends over time in) reporting LTFU and treatment discontinuation in large studies in chronic heart failure published since 1990. Methods and Results—Online databases were systematically reviewed to identify randomized controlled clinical trials (RCTs) in chronic heart failure with >400 participants and utilizing all-cause mortality as a component of the primary or secondary end point. Assessments were made of documentation of treatment discontinuation, LTFU, inclusion of and completeness of a Consolidated Standards Of Reporting Trials (CONSORT) diagram, and whether LTFU was differentiated from withdrawal of consent. Sixty-eight trials were identified, with >154 000 participants. Reasons for treatment discontinuation in pharmacotherapy trials were infrequently reported (35%), particularly in a CONSORT diagram (20%). Eighty-three percent of trials reported LTFU, although only 34% of these differentiated LTFU for vital status from withdrawal of consent. Use of a CONSORT diagram increased over time, although reporting of LTFU in the CONSORT diagram remained low overall at 35%. Conclusions—Participant flow through RCTs in chronic heart failure has not been uniformly reported, and the use of a complete CONSORT diagram has been low, although it seems to be improving. All study participants should be accounted for within a CONSORT diagram in any RCT to enable the practicing cardiologist to interpret how the results should influence his/her clinical practice

Cardiovascular and Noncardiovascular Prescribing and Mortality After Takotsubo:Comparison With Myocardial Infarction and General Population

BACKGROUND: Takotsubo syndrome is an increasingly common cardiac emergency with no known evidence-based treatment.OBJECTIVES: To investigate cardiovascular mortality and medication use after takotsubo syndrome.METHODS: In a case-control study, all patients with takotsubo syndrome in Scotland between 2010-2017 (n=620) were age, sex and geographically matched to individuals in the general population (1:4, n=2,480) and contemporaneous patients with acute myocardial infarction (1:1, n=620). Electronic health record data linkage of mortality outcomes and drug prescribing were analysed using Cox proportional hazard regression models.RESULTS: Of the 3,720 study participants (mean age, 66 years; 91% women), 153 (25%) patients with takotsubo syndrome died over the median of 5.5 years follow up. This exceeded mortality rates in the general population [374 (15%)]; hazard ratio [HR] 1.78 [95% confidence interval 1.48-2.15], P<0.0001), especially for cardiovascular (HR 2.47, [1.81-3.39], P<0.001) but also non-cardiovascular (HR 1.48 [1.16-1.87], P=0.002) deaths. Mortality rates were lower for patients with takotsubo syndrome than those with myocardial infarction (31%, 195/620; HR 0.76 [0.62-0.94], P=0.012), which was attributable to lower rates of cardiovascular (HR 0.61 [0.44-0.84], P=0.002) but not non-cardiovascular (HR 0.92 [0.69-1.23], P=0.59) deaths. Despite comparable medications use, cardiovascular therapies were consistently associated with better survival in patients with myocardial infarction but not in those with takotsubo syndrome. Diuretic (P=0.01), anti-inflammatory (P=0.002) and psychotropic (P<0.001) therapies were all associated with worse outcomes in patients with takotsubo syndrome.CONCLUSIONS: In patients with takotsubo syndrome, cardiovascular mortality is the leading cause of death, and this is not associated with cardiovascular therapy use

Cardiovascular and Noncardiovascular Prescribing and Mortality After Takotsubo:Comparison With Myocardial Infarction and General Population

BACKGROUND: Takotsubo syndrome is an increasingly common cardiac emergency with no known evidence-based treatment.OBJECTIVES: To investigate cardiovascular mortality and medication use after takotsubo syndrome.METHODS: In a case-control study, all patients with takotsubo syndrome in Scotland between 2010-2017 (n=620) were age, sex and geographically matched to individuals in the general population (1:4, n=2,480) and contemporaneous patients with acute myocardial infarction (1:1, n=620). Electronic health record data linkage of mortality outcomes and drug prescribing were analysed using Cox proportional hazard regression models.RESULTS: Of the 3,720 study participants (mean age, 66 years; 91% women), 153 (25%) patients with takotsubo syndrome died over the median of 5.5 years follow up. This exceeded mortality rates in the general population [374 (15%)]; hazard ratio [HR] 1.78 [95% confidence interval 1.48-2.15], P<0.0001), especially for cardiovascular (HR 2.47, [1.81-3.39], P<0.001) but also non-cardiovascular (HR 1.48 [1.16-1.87], P=0.002) deaths. Mortality rates were lower for patients with takotsubo syndrome than those with myocardial infarction (31%, 195/620; HR 0.76 [0.62-0.94], P=0.012), which was attributable to lower rates of cardiovascular (HR 0.61 [0.44-0.84], P=0.002) but not non-cardiovascular (HR 0.92 [0.69-1.23], P=0.59) deaths. Despite comparable medications use, cardiovascular therapies were consistently associated with better survival in patients with myocardial infarction but not in those with takotsubo syndrome. Diuretic (P=0.01), anti-inflammatory (P=0.002) and psychotropic (P<0.001) therapies were all associated with worse outcomes in patients with takotsubo syndrome.CONCLUSIONS: In patients with takotsubo syndrome, cardiovascular mortality is the leading cause of death, and this is not associated with cardiovascular therapy use

Effects of Renin-Angiotensin system blockers on outcomes from COVID-19: a systematic review and meta-analysis of randomised controlled trials

Background and aims: Randomized controlled trials (RCTs) have assessed the effects of renin–angiotensin system (RAS) blockers in adults with coronavirus disease 2019 (COVID-19). This meta-analysis provides estimates of the safety and efficacy of treatment with (vs. without) RAS blockers from these trials. Methods: PubMed, Web of Science, and ClinicalTrials.gov were searched (1 March–12 April 2023). Event/patient numbers were extracted, comparing angiotensin-converting enzyme (ACE) inhibitor/angiotensin-receptor blocker (ARB) treatment with no treatment, for the outcomes: intensive care unit (ICU) admission, mechanical ventilation, vasopressor use, acute kidney injury (AKI), renal replacement therapy (RRT), acute myocardial infarction, stroke/transient ischaemic attack, heart failure, thromboembolic events, and all-cause death. Fixed-effects meta-analysis estimates were pooled. Results: Sixteen RCTs including 3492 patients were analysed. Compared with discontinuation of RAS blockers, continuation was not associated with increased risk of ICU [risk ratio (RR) 0.96, 0.66–1.41], ventilation (RR 0.77, 0.55–1.09), vasopressors (RR 0.92, 0.58–1.44), AKI (RR 1.01, 0.40–2.56), RRT (RR 1.01, 0.46–2.21), or thromboembolic events (RR 1.07, 0.36–3.19). RAS blocker initiation was not associated with increased risk of ICU (RR 0.71, 0.47–1.08), ventilation (RR 1.12, 0.91–1.38), AKI (RR 1.28, 0.89–1.86), RRT (RR 1.66, 0.89–3.12), or thromboembolic events (RR 1.20, 0.06–23.70), although vasopressor use increased (RR 1.27, 1.02–1.57). The RR for all-cause death in the continuation/discontinuation trials was 1.24 (0.80–1.92), and 1.22 (0.96–1.55) in the initiation trials. In patients with severe/critical COVID-19, RAS blocker initiation increased the risk of all-cause death (RR 1.31, 1.01–1.72). Conclusion: ACE inhibitors and ARBs may be continued in non-severe COVID-19 infection, where indicated. Conversely, initiation of RAS blockers may be harmful in critically ill patients. PROSPERO registration number: CRD42023408926

Rationale and methods of a randomized trial evaluating the effect of neprilysin inhibition on left ventricular remodelling

Aims: In patients at high risk of heart failure following myocardial infarction (MI) as a result of residual left ventricular systolic dysfunction (LVSD), the angiotensin receptor neprilysin inhibitor sacubitril/valsartan may result in a greater attenuation of adverse left ventricular (LV) remodelling than renin angiotensin aldosterone system inhibition alone, due to increased levels of substrates for neprilysin with vasodilatory, anti‐hypertrophic, anti‐fibrotic, and sympatholytic effects. Methods: We designed a randomized, double‐blinded, active‐comparator trial to examine the effect of sacubitril/valsartan to the current standard of care in reducing adverse LV remodelling in patients with asymptomatic LVSD following MI. Eligible patients were ≥3 months following MI, had an LV ejection fraction ≤40% as measured by echocardiography, were New York Heart Association functional classification I, tolerant of an angiotensin‐converting enzyme inhibitor or angiotensin receptor blocker at equivalent dose of ramipril 2.5 mg twice daily or greater, and taking a beta‐blocker unless contraindicated or intolerant. Patients were randomized to sacubitril/valsartan (target dose 97/103 mg twice daily) or valsartan (target dose 160 mg twice daily). The primary endpoint will be change in LV end‐systolic volume indexed for body surface area measured using cardiac magnetic resonance imaging over 52 weeks from randomization. Secondary endpoints include other magnetic resonance imaging‐based metrics of LV remodelling, biomarkers associated with LV remodelling and neurohumoral activation, and change in patient well‐being assessed using a patient global assessment questionnaire. Conclusions: This trial will investigate the effect of neprilysin inhibition on LV remodelling and the neurohumoral actions of sacubitril/valsartan in patients with asymptomatic LVSD following MI