Abdallah Al-Mohammad

Myocardial perfusion scintigraphy: the evidence.

This review summarises the evidence for the role of myocardial perfusion scintigraphy (MPS) in patients with known or suspected coronary artery disease. It is the product of a consensus conference organised by the British Cardiac Society, the British Nuclear Cardiology Society and the British Nuclear Medicine Society and is endorsed by the Royal College of Physicians of London and the Royal College of Radiologists. It was used to inform the UK National Institute of Clinical Excellence in their appraisal of MPS in patients with chest pain and myocardial infarction. MPS is a well-established, non-invasive imaging technique with a large body of evidence to support its effectiveness in the diagnosis and management of angina and myocardial infarction. It is more accurate than the exercise ECG in detecting myocardial ischaemia and it is the single most powerful technique for predicting future coronary events. The high diagnostic accuracy of MPS allows reliable risk stratification and guides the selection of patients for further interventions, such as revascularisation. This in turn allows more appropriate utilisation of resources, with the potential for both improved clinical outcomes and greater cost-effectiveness. Evidence from modelling and observational studies supports the enhanced cost-effectiveness associated with MPS use. In patients presenting with stable or acute chest pain, strategies of investigation involving MPS are more cost-effective than those not using the technique. MPS also has particular advantages over alternative techniques in the management of a number of patient subgroups, including women, the elderly and those with diabetes, and its use will have a favourable impact on cost-effectiveness in these groups. MPS is already an integral part of many clinical guidelines for the investigation and management of angina and myocardial infarction. However, the technique is underutilised in the UK, as judged by the inappropriately long waiting times and by comparison with the numbers of revascularisations and coronary angiograms performed. Furthermore, MPS activity levels in this country fall far short of those in comparable European countries, with about half as many scans being undertaken per year. Currently, the number of MPS studies performed annually in the UK is 1,200/million population/year. We estimate the real need to be 4,000/million/year. The current average waiting time is 20 weeks and we recommend that clinically appropriate upper limits of waiting time are 6 weeks for routine studies and 1 week for urgent studies.

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.

Remote monitoring after recent hospital discharge in patients with heart failure: a systematic review and network meta-analysis

Context Readmission to hospital for heart failure is common after recent discharge. Remote monitoring (RM) strategies have the potential to deliver specialised care and management and may be one way to meet the growing needs of the heart failure population. Objective To determine whether RM strategies improve outcomes for adults who have been recently discharged (<28 days) following an unplanned admission due to heart failure. Study design Systematic review and network meta-analysis. Data sources Fourteen electronic databases (including MEDLINE, EMBASE and PsycINFO) were searched to January 2012, and supplemented by hand-searching relevant articles. Study selection All randomised-controlled trials (RCTs) or observational cohort studies with a contemporaneous control group were included. RM interventions included home telemonitoring (TM) (including implanted monitoring devices) with medical support provided during office hours or 24/7 and structured telephone support (STS) programmes delivered via human-to-human contact (HH) or human-to-machine interface (HM). Data Extraction Data were extracted and validity was assessed independently by two reviewers. Results Twenty-one RCTs that enrolled 6317 patients were identified (11 studies evaluated STS (10 of which were HH, while 1 was HM), 9 studies assessed TM, and 1 study assessed both STS and TM). No trial of implanted monitoring devices met the inclusion criteria. Compared with usual care, although not reaching statitistical significance, RM trended to reduce all-cause mortality for STS HH (HR: 0.77, 95% credible interval (CrI): 0.55, 1.08), TM during office hours (HR: 0.76, 95% CrI: 0.49, 1.18) and TM24/7 (HR: 0.49, 95% CrI: 0.20, 1.18). Exclusion of one trial that provided better-than-usual support to the control group rendered each of the above comparisons statistically significant. No beneficial effect on mortality was observed with STS HM. Reductions were also observed in all-cause hospitalisations for TM interventions but not for STS interventions. Care packages generally improved health-related quality-of-life and were acceptable to patients. Conclusions STS HH and TM with medical support provided during office hours showed beneficial trends, particularly in reducing all-cause mortality for recently discharged patients with heart failure. Where ‘usual’ care is less good, the impact of RM is likely to be greater.

Prevalence of hibernating myocardium in patients with severely impaired ischaemic left ventricles

Objective Severe impairment of left ventricular (LV) contraction is associated with an adverse prognosis in patients with ischaemic heart disease. Revascularisation may improve the impaired LV contraction if hibernating myocardium is present. The proportion of patients likely to benefit from this intervention is unknown. Therefore, the prevalence of hibernating myocardium in patients with ischaemic heart disease and severe impairment of LV contraction was assessed. Design From a consecutive series of patients undergoing coronary angiography for the investigation of chest pain or LV impairment, all patients with ischaemic heart disease and an LV ejection fraction (LVEF) ⩽ 30% were identified. These patients underwent positron emission tomography (PET) to detect hibernating myocardium, identified by perfusion metabolism mismatch. Setting A teaching hospital directly serving 500 000 people. Results Of a total of 301 patients, 36 had ischaemic heart disease and an LVEF ⩽ 30%. Twenty-seven patients had PET images, while nine patients were not imaged because of emergency revascularisation (three), loss to follow up (one), inability to give consent (four), and age < 50 years (one, ethics committee guidelines). Imaged and non-imaged groups were similar in LV impairment, demographic characteristics, and risk factor profile. Fourteen patients (52% of the imaged or 39% of all patients with ischaemic heart disease and LVEF ⩽ 30%) had significant areas of hibernating myocardium on PET. Conclusion It is possible that up to 50% of patients with ischaemic heart disease and severely impaired left ventricles have hibernating myocardium.

Management of Chronic Heart Failure in Adults: Synopsis of the National Institute for Health and Clinical Excellence Guideline

DESCRIPTION The National Institute for Health and Clinical Excellence released its first clinical guideline on heart failure in 2003. This synopsis describes the update of that guideline, which was released in August 2010 and discusses the diagnosis, treatment, and monitoring of heart failure. METHODS Guideline developers considered clinical evidence, health economic analyses, clinical expert opinion, and patient views. Systematic literature searches were performed, and an original decision model assessed the cost-effectiveness of serial measurement of serum natriuretic peptide to monitor patients with chronic heart failure. RECOMMENDATIONS First, this guideline update describes the role of serum natriuretic peptide measurement, echocardiography, and specialist assessment in the diagnosis of heart failure. Second, it presents a pathway for pharmacologic treatment, rehabilitation, and pacing therapy (including implantable cardioverter-defibrillator and cardiac resynchronization therapy) for patients with heart failure and left ventricular systolic dysfunction and patients with heart failure and preserved ejection fraction. Finally, it explains the recommendation to monitor patients with heart failure by using serial measurement of serum natriuretic peptide.

Fibroelastoma: case report and review of the literature

A 64 year old woman presented with right hemianaesthesia and was found to have a pansystolic apical murmur with systolic and diastolic posture related plops. Echocardiography revealed a mobile mass on the mitral valve apparatus that was confirmed by magnetic resonance imaging. This was successfully excised and was proven on histopathological examination to be a fibroelastoma. Other cases of fibroelastoma from the literature are reviewed.

Sildenafil in Heart failure (SilHF). An investigator-initiated multinational randomized controlled clinical trial: rationale and design.

Heart failure (HF) is a major clinical problem and, despite advances in both pharmacological and device therapy, the mortality remains high and quality of life poor. Over the last decade there has been growing interest in using phosphodiesterase‐5 (PDE‐5) inhibitors in HF associated with group 2 pulmonary hypertension (PH), with benefits reported on pulmonary haemodynamic and functional status in single‐centre trials

Changing patterns of investigation and treatment of cardiac failure in hospital.

OBJECTIVE: To assess the investigation and treatment of cardiac failure in 1995 and to compare this with management in 1992. DESIGN: Retrospective consecutive case study. SETTING: University teaching hospital. SUBJECTS: All patients (n = 265) discharged from Aberdeen Royal Infirmary in the first quarter (January 1-31 March) of 1995 with a diagnosis of congestive cardiac failure, left ventricular failure, or heart failure (unspecified). These correspond to the International Classification of Diseases 9th revision codings of 428.0, 428.1, and 428.9 respectively. METHODS: Sociodemographic and clinical data were extracted from the case notes of the above subjects and compared with similar data from the final six months of 1992. MAIN OUTCOME MEASURES: The use of echocardiography in confirming the diagnosis and delineating the aetiology of heart failure and the use of angiotensin-converting enzyme (ACE) inhibitors in the treatment of patients diagnosed as having heart failure and without contraindications to these agents. RESULTS: The number of patients discharged in 1995 with a diagnosis including cardiac failure had increased by 55.7% since 1992. The use of echocardiography had also risen from 36.6% to 72% (P < 0.0001) with an associated increase in the proportion of patients discharged on treatment with an ACE inhibitor (40% in 1992 v 55.1% in 1995: P < 0.001). The doses of ACE inhibitors used had also increased significantly (P < 0.001). Most patients with cardiac failure continue to be treated by general physicians, who are less likely to use echocardiography (P < 0.01) or prescribe an ACE inhibitor (P < 0.05) than cardiologists. CONCLUSIONS: There is increasing recognition, more thorough investigation, and improved treatment of heart failure. Despite this there are grounds for concern, both in terms of the adequacy of management and resource implications.

Telemonitoring after discharge from hospital with heart failure: cost-effectiveness modelling of alternative service designs.

Objectives To estimate the cost-effectiveness of remote monitoring strategies versus usual care for adults recently discharged after a heart failure (HF) exacerbation. Design Decision analysis modelling of cost-effectiveness using secondary data sources. Setting Acute hospitals in the UK. Patients Patients recently discharged (within 28 days) after a HF exacerbation. Interventions Structured telephone support (STS) via human to machine (STS HM) interface, (2) STS via human to human (STS HH) contact and (3) home telemonitoring (TM), compared with (4) usual care. Main outcome measures The incremental cost per quality-adjusted life year (QALY) gained by each strategy compared to the next most effective alternative and the probability of each strategy being cost-effective at varying willingness to pay per QALY gained. Results TM was the most cost-effective strategy in the scenario using these base case costs. Compared with usual care, TM had an estimated incremental cost effectiveness ratio (ICER) of £11 873/QALY, whereas STS HH had an ICER of £228 035/QALY against TM. STS HM was dominated by usual care. Threshold analysis suggested that the monthly cost of TM has to be higher than £390 to have an ICER greater than £20 000/QALY against STS HH. Scenario analyses performed using higher costs of usual care, higher costs of STS HH and lower costs of TM do not substantially change the conclusions. Conclusions Cost-effectiveness analyses suggest that TM was an optimal strategy in most scenarios, but there is considerable uncertainty in relation to clear descriptions of the interventions and robust estimation of costs.

Detection of scarred and viable myocardium using a new magnetic resonance imaging technique: blood oxygen level dependent (BOLD) MRI

Background: The identification of viable myocardium in patients with impaired left ventricular contraction secondary to coronary heart disease is important clinically as such myocardium is likely to benefit from revascularisation. Blood oxygen level dependent (BOLD) magnetic resonance imaging (MRI) relies on changes in deoxyhaemoglobin concentration under stress for signal generation and could be used for the differentiation between scarred and viable myocardium. Aim: To assess the signal change on BOLD MRI in viable and scarred myocardium as identified by positron emission tomography (PET). Method: 19 patients with impaired left ventricular contraction and at least one akinetic area were enrolled. They underwent rest and dipyridamole stress MRI, using a double breath hold T2* weighted, ECG gated sequence to produce BOLD contrast images, and cine-MRI for wall thickening assessment. Dynamic perfusion and metabolic PET images followed the MRI. Signal change on BOLD MRI and the wall thickening were compared between rest and stress images in hibernating and scarred segments identified by PET on two short axis slices of mid ventricle, with eight segments each. Results: Using PET, 68 segments were identified as hibernating and 42 as scarred. The hibernating segments were found on BOLD MRI to have an average signal change between rest and stress of −9.53%, compared with −2.15% in the scarred segments (p = 0.008). The average wall thickening was 8.7 mm in the hibernating segments compared with 5.9 mm in the scarred segments (p < 0.0001). Conclusions: BOLD MRI with wall thickening may differentiate scarred and viable myocardium and help identify suitable patients for revascularisation. Further larger studies are needed to establish a threshold for detection, sensitivity, and specificity.