Electrical activity of the heart Myocardial action potential Phase Description Mechanism 0 Rapid depolarisation Rapid sodium influx These channels automatically deactivate after a few ms 1 Early repolarisation Efflux of potassium 2 Plateau Slow influx of calcium 3 Final repolarisation …
Prosthetic heart valves – antithrombotic therapy: bioprosthetic: aspirin mechanical: warfarin + aspirin Prosthetic heart valves The most common valves which need replacing are the aortic and mitral valve. There are two main options for replacement: biological (bioprosthetic) or mechanical. Biological …
Acute coronary syndrome: management NICE produced guidelines in 2010 on the management of unstable angina and non-ST elevation myocardial infarction (NSTEMI). They advocate managing patients based on the early risk assessment using a recognized scoring system such as GRACE (Global …
Atrial fibrillation: rate control – beta blockers preferable to digoxin This question reiterates an important point which frequently comes up in exams – digoxin is no longer first-line for rate control in atrial fibrillation. Her shortness-of-breath is likely to be …
ACE inhibitors have reduced efficacy in black patients and are therefore not used first-line Hypertension: diagnosis and management NICE published updated guidelines for the management of hypertension in 2011. Some of the key changes include: classifying hypertension into stages recommending …
This patient has atrial fibrillation. As a consequence he has had a number of transient ischaemic attacks (TIAs) and hence needs to be anticoagulated with warfarin. In patients who’ve had an ischaemic stroke the guidelines recommend waiting two weeks before …
A prolonged PR interval is seen in around 20-40% of patients Myotonic dystrophy Myotonic dystrophy (also called dystrophia myotonica) is an inherited myopathy with features developing at around 20-30 years old. It affects skeletal, cardiac and smooth muscle. There are …
Patients with neurofibromatosis may develop hypertension for three main reasons: coexistant essential hypertension phaechromocytoma renal vascular stenosis secondary to fibromuscular dysplasia The normal renal function in this patient points away from a diagnosis of renal vascular disease Phaechromocytoma therefore needs …
Infective endocarditis – indications for surgery: severe valvular incompetence aortic abscess (often indicated by a lengthening PR interval) infections resistant to antibiotics/fungal infections cardiac failure refractory to standard medical treatment recurrent emboli after antibiotic therapy Lengthening of the PR interval …
Long QT syndrome Long QT syndrome (LQTS) is an inherited condition associated with delayed repolarization of the ventricles. It is important to recognise as it may lead to ventricular tachycardia and can therefore cause collapse/sudden death. The most common variants …