Which test?

Cardiology

A man presents to a cardiology clinic with atypical chest pain occurring at rest. His GP has arranged a series of extensive investigation which have shown the following. The history is atypical but there is a suggestion of a possibility of exercise induced chest pain.

ECG: Left bundle branch block

CXR: Normal heart size

Blood tests: Normal

Echo: Normal

The patient is keen to have futher investigations. Which would you suggest as the least expensive and invasive test to clarify if he has coronary artery disease that is causing him symptoms?

  • Coronary angiography
  • Cardiac MRI
  • Exercise tolerance test
  • Myocardial Perfusion scan
  • Right and left heart cardiac catherisation

Myocardial Perfusion scan.

A cardiac MRI will give details of the structure and function of the heart as will a left heart catheter. However it will not identify ischaemia.

An ETT would be helpful but he has LBBB. This means the associated ST depression that occurs with ischaemia will not be seen on the ECH and therefore an ETT would be essentially pointless, this leaves us with a MPS.

An MPS will give an idea of cardiac perfusion at both rest and during stress (e.g. induced by drugs at the time of the test). This gives a “dynamic” picture and can identify areas that are ischaemic during stress (hence reversible ischaemia)

This makes it “better” than an angiogram in this situation as its reversible ischemic areas that cause angina. The presence of mild disease at angiogram does not mean that this disease is causing his symptoms.