Andrew Ludman

Statins and cardioprotection--more than just lipid lowering?

Lipid-lowering using HMG-CoA reductase inhibitors or statin therapy forms the cornerstone of medical therapy in the primary and secondary prevention of cardiovascular disease. In addition, to the improvements in lipid profile, the beneficial effects elicited by this class of drugs may be attributed to their diverse variety of non-lipid lowering pleiotropic effects, including improved endothelial function, reduced oxidative stress, less platelet adhesion, and increased atherosclerotic plaque stability. A less appreciated effect of statin therapy that has been reported in experimental studies is its cardioprotective effect with respect to its ability to directly protect the myocardium from the detrimental effects of acute ischaemia-reperfusion injury. In the current article we review the cardioprotective effects of statin therapy beyond serum lipid lowering, the underlying mechanisms involved and the potential implications for patients with coronary heart disease.

Cardiac preconditioning for ischaemia: lost in translation.

Coronary heart disease (CHD) is the leading cause of death worldwide. The development of novel treatment strategies for protecting the myocardium against the detrimental effects of acute ischaemia-reperfusion injury, termed cardioprotection, and for improving clinical outcomes in patients with CHD requires the use of appropriate animal disease models. The concept of cardioprotection was first conceived in the late 1960s and has evolved to include the endogenous cardioprotective phenomenon of ischaemic conditioning, a concept in which the heart can be protected from an episode of acute lethal ischaemia-reperfusion injury by applying brief non-lethal episodes of ischaemia and reperfusion either to the heart itself or to an organ or tissue that is remote from the heart. The brief conditioning episodes of ischaemia and reperfusion can be applied prior to the index ischaemic episode (ischaemic preconditioning), after the onset of the index ischaemic episode (ischaemic perconditioning), or at the onset of reperfusion (ischaemic postconditioning). Elucidation of the signal transduction pathways underlying ischaemic conditioning has identified a variety of pharmacological agents that are capable of reproducing its cardioprotective actions. Despite a wealth of preclinical, experimental animal data demonstrating clear cardioprotective benefits with these treatment strategies, their translation into clinical therapy has been hugely disappointing. This review explores the potential reasons behind this failure; it will focus primarily on the inadequacy of the experimental animal disease models that are currently being used to investigate novel cardioprotective strategies, which on the whole are not adequately representative of the clinical scenario, and finally, we will discuss potential solutions to remedy this problem.

The diagnostic accuracy of the natriuretic peptides in heart failure: systematic review and diagnostic meta-analysis in the acute care setting

Objectives To determine and compare the diagnostic accuracy of serum natriuretic peptide levels (B type natriuretic peptide, N terminal probrain natriuretic peptide (NTproBNP), and mid-regional proatrial natriuretic peptide (MRproANP)) in people presenting with acute heart failure to acute care settings using thresholds recommended in the 2012 European Society of Cardiology guidelines for heart failure. Design Systematic review and diagnostic meta-analysis. Data sources Medline, Embase, Cochrane central register of controlled trials, Cochrane database of systematic reviews, database of abstracts of reviews of effects, NHS economic evaluation database, and Health Technology Assessment up to 28 January 2014, using combinations of subject headings and terms relating to heart failure and natriuretic peptides. Eligibility criteria for selecting studies Eligible studies evaluated one or more natriuretic peptides (B type natriuretic peptide, NTproBNP, or MRproANP) in the diagnosis of acute heart failure against an acceptable reference standard in consecutive or randomly selected adults in an acute care setting. Studies were excluded if they did not present sufficient data to extract or calculate true positives, false positives, false negatives, and true negatives, or report age independent natriuretic peptide thresholds. Studies not available in English were also excluded. Results 37 unique study cohorts described in 42 study reports were included, with a total of 48 test evaluations reporting 15 263 test results. At the lower recommended thresholds of 100 ng/L for B type natriuretic peptide and 300 ng/L for NTproBNP, the natriuretic peptides have sensitivities of 0.95 (95% confidence interval 0.93 to 0.96) and 0.99 (0.97 to 1.00) and negative predictive values of 0.94 (0.90 to 0.96) and 0.98 (0.89 to 1.0), respectively, for a diagnosis of acute heart failure. At the lower recommended threshold of 120 pmol/L, MRproANP has a sensitivity ranging from 0.95 (range 0.90-0.98) to 0.97 (0.95-0.98) and a negative predictive value ranging from 0.90 (0.80-0.96) to 0.97 (0.96-0.98). At higher thresholds the sensitivity declined progressively and specificity remained variable across the range of values. There was no statistically significant difference in diagnostic accuracy between plasma B type natriuretic peptide and NTproBNP. Conclusions At the rule-out thresholds recommended in the 2012 European Society of Cardiology guidelines for heart failure, plasma B type natriuretic peptide, NTproBNP, and MRproANP have excellent ability to exclude acute heart failure. Specificity is variable, and so imaging to confirm a diagnosis of heart failure is required. There is no statistical difference between the diagnostic accuracy of plasma B type natriuretic peptide and NTproBNP. Introduction of natriuretic peptide measurement in the investigation of patients with suspected acute heart failure has the potential to allow rapid and accurate exclusion of the diagnosis.

Effect of erythropoietin as an adjunct to primary percutaneous coronary intervention: a randomised controlled clinical trial

Objective The acute administration of high-dose erythropoietin (EPO) on reperfusing ischaemic myocardium has been reported to halve myocardial infarct (MI) size in preclinical studies, but its effect in ST elevation myocardial infarction patients undergoing primary percutaneous coronary intervention (PPCI) remains unknown. We investigated whether high-dose EPO administered as an adjunct to PPCI reduces MI size. Design Double-blinded, randomised, placebo-controlled. Setting Single tertiary cardiac centre. Patients Fifty-one ST elevation myocardial infarction patients undergoing PPCI. Interventions Patients were randomly assigned to receive either a single intravenous bolus of EPO (50 000 IU) prior to PPCI with a further bolus given 24 h later (n=26) or placebo (n=25). Main outcome measures MI size measured by 24 h area under the curve troponin T and cardiac magnetic resonance imaging performed on day 2 and at 4 months. Results EPO treatment failed to reduce MI size (troponin T area under the curve: 114.6±78 μg/ml EPO vs 100.8±68 μg/ml placebo; infarct mass by cardiac magnetic resonance: 33±16 g EPO vs 25±16 g placebo; both p>0.05). Unexpectedly, EPO treatment doubled the incidence of microvascular obstruction (82% EPO vs 47% placebo; p=0.02) and significantly increased indexed left ventricular (LV) end-diastolic volumes (84±10 ml/m2 EPO vs 73±13 ml/m2 placebo; p=0.003), indexed LV end-systolic volumes (41±9 ml/m2 EPO vs 35±11 ml/m2 placebo; p=0.035) and indexed myocardial mass (89±16 g/m2 EPO vs 79±11 g/m2 placebo; p=0.03). At 4 months, there were no significant differences between groups. Conclusions High-dose EPO administered as an adjunct to PPCI failed to reduce MI size. In fact, EPO treatment was associated with an increased incidence of microvascular obstruction, LV dilatation and increased LV mass. Clinical Trial Registration Information http://public.ukcrn.org.uk/search/StudyDetail.aspx?StudyID=4058 Unique Identifier=Study ID 4058.

Diagnosing and managing acute heart failure in adults: summary of NICE guidance.

Acute heart failure may present de novo in people without known cardiac dysfunction, or as an acute decompensation of known chronic heart failure. Acute heart failure is a common cause of admission to hospital (more than 67 000 admissions in England and Wales each year) and is the leading cause of hospital admission in people aged 65 years or more in the United Kingdom.1 European registry data show that nearly 50% of people admitted to hospital with acute heart failure are re-admitted within 12 months,2 and a third of people with acute heart failure die within a year of their first hospital admission.1 The diagnosis of heart failure can be challenging because of non-specific symptoms and clinical signs, and there is evidence of wide variation in the way people with acute heart failure are managed.1 This article summarises the most recent recommendations from the National Institute for Health and Care Excellence (NICE) on acute heart failure.3 NICE recommendations are based on systematic reviews of the best available evidence and explicit consideration of cost effectiveness. When minimal evidence is available, recommendations can be based on the Guideline Development Group’s experience and opinion of what constitutes good practice. Evidence levels for the recommendations are given in italic in square brackets. ### Organisation of care

A place of safety

Throughout our medical training, my wife and I have often bemoaned the confused elderly person who appears in the casualty department for no apparent medical reason in the middle of the night. A recent event has helped change our opinion. We were returning from a wedding late at night and came across a confused elderly woman wandering outside our house. She was wearing only a …

How research is affected

The Mental Capacity Act 2005 could be regarded as protective to both patient and clinician in the circumstances of routine medical care.1 It has also helped clarify the issue of capacity when patients are asked to take part in research studies. Sections 30-34 of the act deal …

Safety and clinical outcome of erythropoiesis-stimulating agents in patients with ST-elevation myocardial infarction: a meta-analysis of individual patient data.

BACKGROUND Erythropoiesis-stimulating agents (ESAs) have been investigated in small studies in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Erythropoiesis-stimulating agents did not show a clear effect on left ventricular function or clinical outcome, but some studies suggested an increased risk of thromboembolic events. METHODS A systematic literature search in MEDLINE was performed, until December 2012. We included randomized clinical trials investigating the effect of ESAs in STEMI patients undergoing primary PCI, with ≥30 days of follow-up. The primary end point was a composite of all-cause mortality, myocardial infarction, and stent thrombosis after PCI. Secondary end point was all-cause mortality. RESULTS Individual patient data were obtained from 10 of 11 trials, including 97.3% (1,242/1,277) of all patients randomized to control (n = 600) or to ESAs (n = 642). Baseline characteristics were well balanced between the treatment allocations. Mean follow-up time was 248 (±131) days. The primary end point occurred in 3.5% (20/577) in the control group and in 2.1% (13/610) in the ESA group (hazard ratio for ESAs, 0.63; 95% CI [0.31-1.27]; P = .20). Mortality occurred in 13 (2.3%) in the control group and 5 (0.8%) in the ESA group (hazard ratio for ESAs, 0.38; 95% CI [0.13-1.06]; P = .06). CONCLUSIONS Erythropoiesis-stimulating agent administration does not result in an increased risk of adverse cardiac events in STEMI patients undergoing primary PCI. Results of ongoing studies may provide further insight to the potential beneficial clinical effects of ESAs in STEMI patients.

Cost-effectiveness analysis of natriuretic peptide testing and specialist management in patients with suspected acute heart failure

OBJECTIVES To determine the cost-effectiveness of natriuretic peptide (NP) testing and specialist outreach in patients with acute heart failure (AHF) residing off the cardiology ward. METHODS We used a Markov model to estimate costs and quality-adjusted life-years (QALYs) for patients presenting to hospital with suspected AHF. We examined diagnostic workup with and without the NP test in suspected new cases, and we examined the impact of specialist heart failure outreach in all suspected cases. Inputs for the model were derived from systematic reviews, the UK national heart failure audit, randomized controlled trials, expert consensus from a National Institute for Health and Care Excellence guideline development group, and a national online survey. The main benefit from specialist care (cardiology ward and specialist outreach) was the increased likelihood of discharge on disease-modifying drugs for people with left ventricular systolic dysfunction, which improve mortality and reduce re-admissions due to worsened heart failure (associated with lower utility). Costs included diagnostic investigations, admissions, pharmacological therapy, and follow-up heart failure care. RESULTS NP testing and specialist outreach are both higher cost, higher QALY, cost-effective strategies (incremental cost-effectiveness ratios of £11,656 and £2,883 per QALY gained, respectively). Combining NP and specialist outreach is the most cost-effective strategy. This result was robust to both univariate deterministic and probabilistic sensitivity analyses. CONCLUSIONS NP testing for the diagnostic workup of new suspected AHF is cost-effective. The use of specialist heart failure outreach for inpatients with AHF residing off the cardiology ward is cost-effective. Both interventions will help improve outcomes for this high-risk group.

Association of haemodynamic changes measured by serial central venous saturation during ultrafiltration for acutely decompensated heart failure with diuretic resistance and change in renal function

BACKGROUND Patients with acute decompensated heart failure with diuretic resistance (ADHF-DR) have a poor prognosis. The aim of this study was to assess in patients with ADHF-DR, whether haemodynamic changes during ultrafiltration (UF) are associated with changes in renal function (Δcreatinine) and whether Δcreatinine post UF is associated with mortality. METHODS Seventeen patients with ADHF-DR underwent 20 treatments with UF. Serial bloods (4-6 hourly) from the onset of UF treatment were measured for renal function, electrolytes and central venous saturation (CVO2). Univariate and multivariate analysis were performed to assess the relationship between changes in markers of haemodynamics [heart rate (HR), systolic blood pressure (SBP), packed cell volume (PCV) and CVO2] and Δcreatinine. Patients were followed up and mortality recorded. Cox-regression survival analysis was performed to determine covariates associated with mortality. RESULTS Renal function worsened after UF in 17 of the 20 UF treatments (baseline vs. post UF creatinine: 164±58 vs. 185±69μmol/l, P<0.01). ΔCVO2 was significantly associated with Δcreatinine [β-coefficient of -1.3 95%CI (-1.8 to -0.7), P<0.001] and remained significantly associated with Δcreatinine after considering changes in SBP, HR and PCV [P<0.001]. Ten (59%) patients died at 1-year and 15(88%) by 2-years. Δcreatinine was independently associated with mortality (adjusted-hazard ratio 1.03 (1.01 to 1.07) per 1μmol/l increase in creatinine; P=0.02). CONCLUSIONS Haemodynamic changes during UF as measured by the surrogate of cardiac output was associated with Δcreatinine. Worsening renal function at end of UF treatment occurred in the majority of patients and was associated with mortality.