The heart and potassium: a banana republic.

The importance of potassium in maintaining stable cardiac function is a clinically understood phenomenon. Physiologically the importance of potassium in cardiac function is described by the large number of different kinds of potassium ions channels found in the heart compared to channels and membrane transport mechanisms for other ions such as sodium and calcium. Potassium is important in physiological homeostatic control of cardiac function, but is also of relevance to the diseased state, as potassium-related effects may stabilize or destabilize cardiac function.

Using the 12-lead ECG to diagnose acute myocardial infarction in the presence of left bundle branch block.

The 12-lead ECG is a powerful clinical tool used to risk stratify patients presenting to the emergency department with chest pain. In particular the ECG is used as the diagnostic tool to instigate reperfusion therapy in patients with acute coronary syndromes. The ECG features of acute myocardial infarction (AMI) may be masked by the presence of left bundle branch block (LBBB) and the ECG may be difficult to interpret.

Detecting failed thrombolysis in the accident and emergency department.

The primary objective in managing a patient with ST segment elevation myocardial infarction (STEMI) is to establish reperfusion in the infarct-related artery and to maintain it. Two approaches to coronary reperfusion are used in the UK - primary angioplasty and intravenous thrombolysis. Primary angioplasty is the gold standard approach to managing STEMI, but in the UK (due to financial, resource and personnel limitations) this is not the first-line treatment.

Managing thrombolysis in the accident and emergency department.

The optimal management of acute myocardial infarction (AMI) today is founded upon the 'open artery' theory and driven by the need for early reperfusion strategies. Numerous randomised controlled trials demonstrate the unequivocal benefit of thrombolytic therapy in reducing mortality and improving long-term prognosis. These benefits are most striking when the thrombolytic therapy is given early.