Clinical articles

The role of cardiac computed tomography (CT) in clinical practice is constantly evolving. Early machines were only capable of measuring coronary calcification. Advances in temporal and spatial resolution, especially the introduction of 64-detector rows, now mean that high-quality non-invasive angiograms are possible in most patients. This review will outline the capabilities and limitations of coronary artery imaging with CT, and also highlight areas that differentiate CT from X-ray angiography, including direct plaque visualisation and potential vulnerable plaque identification.

Ventricular fibrillation (VF) is induced at the time of implantable cardioverter defibrillator (ICD) implantation in the UK, typically at least twice, with defibrillation ≥10 J below the maximum output. With the advent of modern leads/devices a single test may be sufficient.

A 72-year-old man, who underwent coronary artery bypass grafting 14 years previously, presented with sharp posterior chest pain and presyncope.

Ictal bradycardia/asystole is a poorly recognised cause of collapse late in the course of a typical complex partial seizure. Its recognition is important as it might potentially lead to sudden unexpected death in epilepsy (SUDEP). We present five patients with intractable complex partial seizures who had associated ictal bradycardia/asystole. All the patients underwent cardiac pacing to potentially prevent SUDEP. It is important to recognise and treat ictal asystole early, and to achieve this there is need for both an increase in epilepsy monitoring beds and a recognition of the potential role of implantable loop recorders in the evaluation of patients with epilepsy who clinically appear to be at increased risk for ictal asystole.

Depression and anxiety are commonly experienced by cardiac patients and are associated with reduced quality of life and mortality, but the evidence for the effectiveness of medical and psychological treatments for depression has been mixed.

Coronary heart disease is a leading cause of mortality and morbidity worldwide. Risk factor modification through a robust cardiac rehabilitation programme is rewarding and accounts for the major decline in mortality due to coronary heart disease in the long term,1 thus, making it an essential part of the curriculum. With this in mind, we conducted an observational study based on the feedback of 114 medical students over a four-year period about exercise tutorial in cardiac rehabilitation. Data were collected on a 10-point scale questionnaire. An overwhelming majority of students (more than 90%) were deeply impressed by this novel approach of being taught about cardiac rehabilitation. They strongly recommended this unique approach, as not only an effective tutorial on cardiac rehabilitation, but also advocated it enthusiastically as a general teaching method.

Low-dose aspirin is of value in the long-term management of vascular disease, and the giving of aspirin to patients believed to be experiencing an acute myocardial infarction (AMI) is standard practice for paramedics and doctors in most countries. Given during infarction, aspirin may disaggregate platelet microthrombi and may reduce the size of a developing thrombus. Effects of aspirin other than on platelets have also been suggested and these include an increase in the permeability of a fibrin clot and an enhancement of clot lysis. Animal experiments have also shown a direct effect of aspirin upon the myocardium with a reduction in the incidence of ventricular fibrillation.

Randomised trials have shown that the earlier aspirin is taken by patients with myocardial infarction, the greater the reduction in deaths. We suggest, therefore, that patients known to be at risk of an AMI, including older people, should be advised to carry a few tablets of soluble aspirin at all times, and chew and swallow a tablet immediately, if they experience severe chest pain. 

Intra-coronary imaging has become a cornerstone of visualising atherosclerotic coronary artery disease and also to guide the therapy in selected high-risk cases. Optical coherence tomography (OCT) is an imaging modality quite similar to intravascular ultrasound (IVUS), but uses light instead of sound. In the second article on contemporary coronary imaging, the potential of OCT is discussed.

Infective endocarditis (IE) causes high rates of morbidity and mortality. Clinical management is problematic if there are uncertainties over the identity, viability or antibiotic susceptibility of the causative organism. Between 10% and 30% of IE blood cultures are negative, usually a result of prior antimicrobial therapy, but also occurring when causative micro-organisms are non-cultivable or fastidious. While evidence-based guidelines exist for treatment of IE caused by defined agents, clinicians are often faced with the dilemma of IE of unproven aetiology. Duration of empirical therapy is usually titrated against overall clinical response and non-specific laboratory markers of inflammation, but these may bear little relation to ongoing microbial activity in the heart valve. There is an increasing need for more specific, sensitive and rapid tests for the identification of causative organisms. Nucleic acid amplification technologies (NAATs) show promise for rapid detection of pathogen nucleic acid in blood or tissue. This review discusses the developments in this field, and the potential for the application of NAATs to improve aetiological identification in IE.

There is much debate about the optimal sedation strategy for transoesophageal echocardiography (TEE). Despite previous studies demonstrating the potential benefits of combining opiates and benzodiazepines for conscious sedation, and previous published national surveys and recommendations, sedation practice for TEE in clinical practice varies widely within the UK. All UK centres routinely use midazolam, but only 7% of centres use it in combination with an opiate: 14% of hospitals report no routine use of sedation for TEE. There
is no British Society of Echocardiography (BSE) recommended TEE sedation protocol within the UK and even where guidelines exist locally, 82% of operators report being unaware of their details. Consequently, a wide range of sedative doses are used and many patients are reported to be over-sedated. We developed a new protocol for conscious sedation using intravenous pethidine and midazolam for TEE and have shown it to be safe and effective when implemented within an existing TEE service.