My GP dismissed the possibility of it being angina, and suggested it may be a muscular issue, and to go back to them if it got worse (I am 72).

John Coleridge, Cheshire.

The symptom you describe is, in my view, highly suggestive of angina.

The textbook description of angina is that it causes chest pain that may radiate into the left arm.

But my experience built up over many decades is that it rarely presents this way. In fact, I've rarely seen angina patients with pain in the left shoulder or arm: typically, it leads to central chest pain, though the severity varies.

Angina is caused by a partial narrowing of the arteries. The pain occurs when the heart is working harder (for example, during exercise) and not enough blood is getting through.

You may find that your symptoms worsen if you take your walk after a meal and it may be more likely to happen in colder weather (in both instances the heart has to work harder). In some patients the angina pain is felt in the neck and jaw, while in others it's the upper abdomen. But the sensation can spread to both arms — or the right arm only.

As well as the pain, you might be slightly breathless. But the chief pattern to watch for is that this pain starts on exertion and stops when you rest.

I think you should see a cardiologist for further investigations.