Medicine RSS feed: Current Issue. Medicine is a continually updated, evidence based review journal covering internal medicine and its subspecialties. Medicine is an authoritative and comprehensive resource that provides all clinicians, irrespective of specialty, with ready access to up-to-date information on mechanisms of disease, diagnosis and management so that patient care may be optimized. The layout of the Journal, including the extensive use of colour and illustration, enables fast assimilation of key information. For ease of reference, Medicine is available in journal format and online. Medicine has an outstanding Editorial Board, plus an eminent group of 35 Chapter editors and over 750 authors, all of whom are recognized experts in their field. The editorial content of the Journal is assured by a rigorous peer review process. http://www.medicinejournal.co.uk/?rss=yesElsevier Inc.en © 2010 Published by Elsevier Inc. All rights reserved. Medicine1357-3039387July 2010 © 2010 Published by Elsevier Inc. All rights reserved. healthpermissions@elsevier.comhttp://www.medicinejournal.co.uk/article/PIIS1357303910001350/abstract?rss=yesContents10.1016/S1357-3039(10)00135-0Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XOFCOFChttp://www.medicinejournal.co.uk/article/PIIS1357303910001374/abstract?rss=yesEditorial Board10.1016/S1357-3039(10)00137-4Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-Xiihttp://www.medicinejournal.co.uk/article/PIIS1357303910001027/abstract?rss=yesAbstract: Despite centuries of writings and research into cardiac anatomy and function, the topic is still advancing, particularly in reference to clinical applications and embryological significance. This article presents the heart with reference to the classical anatomical position and attempts to clarify the nomenclature that is most commonly used by anatomists. We encourage clinicians to use the same terminology. The references are from an excellent compilation on the heart in Clinical Anatomy.Anatomy of the heartRobert H. Whitaker10.1016/j.mpmed.2010.04.005Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XThe normal heart333335http://www.medicinejournal.co.uk/article/PIIS1357303910000836/abstract?rss=yesAbstract: The mechanical events of the cardiac cycle provide the circulation with normal cardiac output and blood pressure. This requires an appropriate venous return, regulation of outflow resistance, a normal myocardial contractile state, and heart rate control, together with an adequate supply of oxygenated blood via the coronary circulation. Other neural influences contribute to cardiac regulation, including natriuretic peptides, and the renin–angiotensin system. The atria and ventricles are richly supplied with adrenergic nerves that may augment cardiac function, particularly with increased cardiac output during exercise. Inhibitory vagal fibres are largely confined to the sinus and atrioventricular nodes. Exercise causes increased sympathetic outflow, with a decrease in peripheral vascular resistance, and increased cardiac output, heart rate, systolic blood pressure and venous return. Regular rhythmic exercise has a training effect, which enhances cardiac performance. This is important for the maintenance of many aspects of cardiovascular health.Physiology of the normal heartDavid E.L. Wilcken10.1016/j.mpmed.2010.03.014Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XThe normal heart336339http://www.medicinejournal.co.uk/article/PIIS1357303910000824/abstract?rss=yesAbstract: The heart is composed of muscle cells (cardiomyocytes) that account for most of the heart mass and generate its pumping force. Other cell types (fibroblasts, vascular endothelial cells, vascular smooth muscle cells) and the extracellular matrix also play key roles in cardiac function, both in health and in disease. Excitation–contraction coupling links the electrical activation of cardiomyocytes to cellular contraction. Calcium is a key second messenger in this process; its entry into the cell triggers further calcium release from the sarcoplasmic reticulum, which then activates the contractile machinery. Subsequent reduction in calcium concentration brings about cardiac relaxation, which is necessary for the heart to re-fill. Calcium also regulates other critical processes in the heart including transcription of genes and the matching of energy supply from the mitochondria with cellular demand. In health, the contractile function of the heart is regulated by several factors, including its loading conditions, autonomic influences and many locally produced autocrine/paracrine agents. These factors alter contractile strength through two main mechanisms, namely the modulation of the calcium transient within cardiomyocytes and/or changes in myofilament sensitivity to calcium.Biochemistry and physiology of cardiac muscleAlex Sirker, Ajay M. Shah10.1016/j.mpmed.2010.03.013Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XThe normal heart340343http://www.medicinejournal.co.uk/article/PIIS1357303910001003/abstract?rss=yesAbstract: A full history and physical examination remain an integral part of assessment of the cardiac patient in the twenty-first century. They allow easier rapport with the patient and facilitate assessment of the best management. It is profoundly unwise to rely solely on the results of imaging and other investigations. Total reappraisal is necessary when the history, examination and investigations are discordant – no investigation is infallible and the clinical assessment should never be ignored. Here we summarize the four main symptoms of cardiological problems (chest pain/discomfort, breathlessness, palpitations and light-headedness/syncope) and discuss how they will present in the history. Also, appropriate sections of the examination are detailed.History and examination of the cardiovascular systemLawrence Cotter10.1016/j.mpmed.2010.04.003Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XClinical assessment344347http://www.medicinejournal.co.uk/article/PIIS1357303910001015/abstract?rss=yesAbstract: This contribution details the features that should be looked at on an ECG to determine whether or not it is normal. It describes the abnormalities found in certain conditions including atrial enlargement, ventricular hypertrophy, acute chest pain, ST elevation myocardial infarction, and syncope with many illustrations.ECGPatrick Davey10.1016/j.mpmed.2010.04.004Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations348356http://www.medicinejournal.co.uk/article/PIIS1357303910000812/abstract?rss=yesAbstract: Conventional chest radiography remains an important imaging tool for patients with suspected cardiac disease and is usually the first-line imaging investigation performed in both the acute hospital setting and in patients referred from the community. Accurate interpretation allows the diagnosis of structural cardiac abnormalities and of associated abnormalities of the pulmonary vasculature and airways. As picture archiving and communication systems (PACS) are now widely available throughout Europe and the USA, more doctors will have access to images and therefore need to improve their interpretation skills. This chapter provides a basic introduction to the interpretation of a normal chest radiograph and a more detailed look at its use in cardiac disease.The chest radiograph in heart diseaseF.V. Gleeson, A.C. Rayner10.1016/j.mpmed.2010.03.012Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations357361http://www.medicinejournal.co.uk/article/PIIS1357303910000800/abstract?rss=yesAbstract: Exercise electrocardiography (exercise ECG) is the least expensive and most readily available functional test for atherosclerotic coronary artery disease (CAD). Its major weakness is limited accuracy, with a false negative rate of around 30% (sensitivity 70%), and a false positive rate of around 20% (specificity 80%). It provides diagnostic and prognostic information in patients presenting with suspected angina; when applied to those with known CAD it can stratify risk and guide management. Patients with resting ECG abnormalities (e.g., complete left bundle branch block) or with non-cardiac problems that limit their exercise tolerance, are better investigated by other tests. We describe how to perform an exercise ECG, the information yielded by the test and the integration of this information with clinical data. With greater access to more accurate tests, the future of exercise ECG as the workhorse for diagnosis of CAD is uncertain.Exercise electrocardiographyDavid Sprigings, Matthew J. Daniels10.1016/j.mpmed.2010.03.011Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations362366http://www.medicinejournal.co.uk/article/PIIS1357303910000988/abstract?rss=yesAbstract: Cardiac electrophysiology is the subspecialty of cardiology dealing with heart rhythm disorders, particularly the investigation and management of brady- and tachyarrhythmias, syncope and the prevention of sudden cardiac death. Recent years have seen significant developments in our understanding of arrhythmias. Recent technological developments include ever smaller and more complex implantable pacing devices, the ability to map an arrhythmia circuit in three dimensions, potentially in one beat and to destroy small areas of myocardium safely known to be critical to a particular arrhythmia. These have led to a dramatic expansion in our ability to treat heart rhythm problems. This article will focus on the diagnostic tools which can be used to investigate these conditions and its sister article will deal with some of the treatment strategies.Electrophysiological investigationMartina Muggenthaler, Razeen Gopal, Richard Schilling, Nicholas Gall10.1016/j.mpmed.2010.04.001Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations367370http://www.medicinejournal.co.uk/article/PIIS1357303910000794/abstract?rss=yesAbstract: Echocardiography – the investigation of the heart with ultrasound – is the most frequently used cardiac imaging modality. Transthoracic echocardiography is a powerful tool to evaluate the structure and function of the heart. Further evaluation is possible with transoesophageal echocardiography. However, its higher resolution and image quality are accompanied by a small risk of complications. Stress echocardiography allows identification of patients with significant coronary artery disease with high sensitivity and specificity. The aim of this article is to outline the information that echocardiography can provide and the clinical situations where it is indicated. Further advanced applications such as contrast and three-dimensional echocardiography will also be discussed.EchocardiographyMatthias Paul, Lindsay Smith, Mark Monaghan10.1016/j.mpmed.2010.03.010Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations371375http://www.medicinejournal.co.uk/article/PIIS1357303910000848/abstract?rss=yesAbstract: Nuclear cardiology is a well established and commonly performed technique which provides physiological information regarding myocardial perfusion and function. Three techniques are described; myocardial perfusion scintigraphy (MPS), radionuclide ventriculography (RNV) and positron emission tomography (PET). MPS is useful in patients unable to complete an exercise test or those likely to produce a false positive result; in particular women, diabetics and those with left bundle branch block. The technique has also been validated in patients undergoing non-cardiac surgery, before and after coronary revascularization and in the assessment of myocardial viability. MPS relies on the changes in cellular uptake of radioactive tracers at rest and during myocardial stress. Matched defects represent sites of infarction whereas mismatch between normal perfusion at rest and reduced perfusion during stress indicates ischaemia. Cardiac risk is proportional to the size of the perfusion defect. RNV relies on blood pool labelling to assess regional ventricular function with excellent reproducibility. Cardiac PET scanning is more commonly used for the assessment of myocardial viability; however, newly available perfusion tracers make it a realistic technique for the assessment of coronary artery disease.Nuclear imagingMargaret Loudon, Nik Sabharwal10.1016/j.mpmed.2010.03.015Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations376379http://www.medicinejournal.co.uk/article/PIIS1357303910000861/abstract?rss=yesAbstract: Recent developments in computed tomography (CT) technology permit imaging of the coronary arteries. Non-enhanced CT is used to perform coronary artery calcium scoring, which is useful to stratify the risk of future coronary events but does not allow assessment of stenosis. Contrast-enhanced CT enables angiographic evaluation of the coronary artery lumen. The high negative predictive value of coronary CT angiography (CTA) makes it a useful test to rule out the presence of significant coronary stenoses, especially in those patients with an intermediate pre-test likelihood of coronary artery disease. Coronary CTA also has potential to aid triage of patients with acute chest pain in the emergency department. Coronary artery bypass grafts can be reliably assessed using CT. Intracoronary stents are difficult to image due to artefacts caused by metal, often precluding detection of in-stent restenosis. There is emerging evidence of the ability of CT to characterize atherosclerotic plaque, which may help identify those plaques at most risk of rupture. The possibility of myocardial perfusion imaging using cardiac CT is the subject of current investigation.Cardiac computed tomographyNevin T. Wijesekera, Simon P.G. Padley10.1016/j.mpmed.2010.03.017Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations380383http://www.medicinejournal.co.uk/article/PIIS135730391000085X/abstract?rss=yesAbstract: Magnetic resonance imaging (MRI) uses the magnetic properties of the hydrogen nucleus, radio waves and powerful magnets to provide high-quality still and cine images of the cardiovascular system, with and without the use of an exogenous contrast (gadolinium). Cardiovascular MRI (CMR) is considered the gold standard method for the three-dimensional analysis of cardiothoracic anatomy, the assessment of global and regional myocardial function, and viability imaging (late gadolinium enhancement technique). It is also an excellent method for the identification of myocardial ischaemia using the first-pass perfusion technique. Coronary imaging with CMR is feasible, and indicated particularly for anomalous coronaries. However, its spatial and temporal resolution is inferior to computed tomography or conventional angiography, and the identification and grading of stenoses remains challenging. In future, molecular imaging may allow visualization of unstable plaque. Oedema detection is another promising tool, which adds a new dimension to imaging in patients with acute coronary syndromes. CMR also provides important prognostic data for many cardiovascular diseases. CMR is now an essential component of advanced cardiovascular imaging, and it is anticipated that its role will continue to grow in the future.Cardiovascular magnetic resonance imagingTheodoros Karamitsos, Stefan Neubauer10.1016/j.mpmed.2010.03.016Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations384389http://www.medicinejournal.co.uk/article/PIIS1357303910001052/abstract?rss=yesAbstract: Cardiac catheterization involves insertion of fine-bore tubes (catheters) into the heart through cannulae inserted into a peripheral artery or vein. Procedures are commonly performed via the femoral vessels. However, the radial artery approach has the best safety record and is becoming increasingly popular. Brachial access is now rarely used because of its complexity and potentially higher complication rates. Left heart catheterization is used to diagnose or evaluate coronary artery disease and valvular heart disease. Left ventriculography, selective coronary angiography and measurement of pressure in the left ventricle (LV) are routinely performed. Aortography is performed in patients with aortic regurgitation or aortic root dilatation. Left ventriculography allows visual assessment of LV size/function as well as measurement of LV pressure and systolic pressure gradients across diseased aortic valves. Coronary angiography provides information on coronary anatomy. Right heart catheterization allows measurement of haemodynamic data and oxygen saturations from the right heart chambers and pulmonary circulation. It provides information on right ventricular function, pulmonary artery pressure, right-sided and left-sided filling pressures, cardiac output and left-to-right shunts. Combined right and left catheterization is used in the comprehensive evaluation of patients with complex cardiac conditions, particularly those with valvular heart disease, intra-cardiac shunts or heart failure.Cardiac catheterizationDeepak Goyal, Karim Ratib, Rajay Narain, Jim Nolan10.1016/j.mpmed.2010.04.006Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XInvestigations390394http://www.medicinejournal.co.uk/article/PIIS1357303910001283/abstract?rss=yes filling of the coronary arteries is maximal at the beginning of systoleSelf-assessment/CPD10.1016/j.mpmed.2010.05.008Medicine 38, 7 (2010)2010-07-01Medicine2010-07-01387S1357-3039(10)X0007-XSelf-assessment395395