4 8.1. Incidence and Prevalence. SLE is one of the most common multisystem autoimmune disorders in the world with a variable prevalence but when investigated a preva- lence of 51/100 000 in 2003 [3]. The male-female ratio is approximately 9 : 1 with a higher incidence in people of a non-Caucasian background [4]. The incidence of cardiac involvement at postmortem is approximately forty percent, but only six percent of patients had echocardiographic evidence of impairment, and only 1 death in a cohort of over 500 patients was attributable to cardiac involvement [5]. 8.2. Diagnosis of SLE: A Noncardiac Perspective. The diag- nosis of SLE without the advantage of biopsy specimens remains based on the 1997 update from the American College of Rheumatologists and is based on four positive criteria out of eleven [6] reproduced below: (1) malar rash, (2) discoid rash, (3) photosensitivity, (4) oral ulcers, (5) nonerosive arthritis, (6) pleuritis or pericarditis, (7) renal disorder, (8) neurological disorder, (9) haematological disorder, (10) immunological disorder, for example, positive anti- bodies to DS-DNA, SM, or phospholipids, (11) positive ANA. As many patients do not make it as far as a deﬁnitive biopsy, diagnosis remains based on a combination of clinical features and immunological phenomena as described in the above guidelines. 8.3. Cardiac Pathology in SLE. There are a number of possible cardiac manifestations of SLE, the most common forms being pericarditis, myocarditis, nonbacterial verru- cous endocarditis, coronary artery disease, coronary arteritis, premature coronary atherosclerosis, congestive heart failure, cardiac arrhythmias, pulmonary hypertension, and conduc- tion disturbances. Symptoms and severity of the disease are linked to the pattern of autoantibodies expressed, in addition, the inter- individual variable expression of antibodies to ds-DNA, Ro, or anticardiolipin, permit a subtyping of SLE and indicate that there may well be great overlapping of SLE and other conditions such as dermatomyositis, progressive systemic sclerosis, or Sjo¨gren’s syndrome. SLE manifests as we see above in many ways, but we will focus on myocardial disease and accelerated atherosclerosis, as they constitute the major primary cardiac problems. SLE is the classical example of an immune complex (IC) associated systemic autoimmune disease, and that Cardiology Research and Practice this immune complex deposition results in an inﬂam- matory response involving the myocardium, pericardium, and perivascular tissue of cardiac blood vessels [7]. This inﬁltration by immune complexes leads to complement activation and a generalised polymorph invasion followed by myocardial damage [8]. The other major manifestation that we will consider is accelerated atherosclerosis, and it has been with approx- imately ﬁfty percent of all suﬀerers having signiﬁcant atherosclerosis at postmortem [9]. The underlying mecha- nism is thought to be similar to that of the general population but at an accelerated rate due to inﬂammatory endothelial dysfunction [8]. The medications involved in treating SLE may also con- tribute, such as azathioprine-induced endothelial dysfunc- tion [8]. There are also some suggestions as with our patient that there is an alteration of coronary microcirculation leading to ischaemic damage with normal coronaries on angiography similar to our patient. 8.4. Cardiac Imaging in SLE. Before we can begin on imag- ing, the key ﬁrst step in investigation of SLE-related cardiac disease is the electrocardiogram for analysis of arrhythmias, ischaemic change, and left ventricular function. While there is no particular consensus on what imaging is required when cardiac involvement with SLE is suspected, the most reasonable ﬁrst step is echocardiography as with many cardiac diseases. Echocardiography can help diag- nose SLE-related pericarditis, systolic dysfunction, valvu- lar involvement, and cavity thrombus formation with a good sensitivity [10]. While transthoracic echocardiography is more than acceptable in routine practice, sometimes transesophageal echocardiography may be needed for closer analysis of valve structure and function and is thus more sensitive [11]. 3D echocardiography does not really add much to diagnosis except for exclusion of other types of cardiomyopathy such as noncompaction cardiomyopathy. The next step in investigation, we would suggest, in patients with cardiomyopathy and SLE is coronary angiogra- phy as the rate of atherosclerosis is markedly raised compared to control subjects [12]. This is based on the fact that there can be thrombus within the coronary arteries but the main step is to look for signiﬁcant coronary artery disease causing ischaemia, as this is the most common factor for cardiomyopathy in normal people and myocardial infarction rates are ﬁfty-times higher in SLE [13]. Other imaging modalities have been used to look for ischaemia such as myocardial perfusion scanning [14], cardiac CT angiography [15], and stress echocardiography [16]. As these techniques and cardiac MRI angiography become more widespread in clinical practice, we feel they will to a large extent, replace invasive angiography. If angiography has shown normal coronary arteries and there is evidence of an SLE cardiomyopathy process, then magnetic resonance imaging should be undertaken to look for changes in structure such as ﬁbrosis and scarring, and in some cases MRI has been used to check function in patients who have clinically improved [17].