Apex Beat Missing - What to do?

Looking for the cardiac apex is an important part in the cardiovascular examination, be it the long case or short case examination.

If the cardiac apex is not palpable in the supine position (patient propped up at 45 degrees of course), then the next step is to request the patient to raise the left arm above his or her head and turn to the left lateral position. This enables the cardiac apex to be closer to the thoracic wall thus easier to be palpated.

However, in some situations, the cardiac apex remain elusive in its usual expected anatomical location. Some possible causes are:

1. Thick chest wall

- the thick subcutaneous tissue makes it difficult to feel the apex 

2. Emphysema

- the overlying hyperinflated lung tissue masks the cardiac apex and makes it more difficult to detect

- a hyperinflated chest wall can be suspected when the antero-posterior chest thickness is similar or greater than the distance between the nipples (this is an informal tip, and I do not think it is verified or supported in any medical textbook to my knowledge). 

3. Pericardial effusion

- Increased fluid accumulation in the pericardial layers may "muffle" the cardiac apex making it less easy to detect by palpation over the precordium. 

- However, a significant pericardial effusion may be required to be present before causing "loss" of apex beat. Thus there may be other signs to suggest a significant pericardial effusion e.g. reduced pulse volume, elevated jugular venous pressure and muffled heart sounds. 

4. Dextrocardia

- After satisfying yourself that the cardiac apex is not located within the left hemithorax, try looking for it on the right side instead. 

5. Is the patient "alive"?

- This possibility is unlikely in the exam setting, but of course, just to be sure, ensure there is spontaneous breathing and peripheral pulses are also palpable (especially the carotid pulse) at the same time. 😆

- However this scenario may be possible in the regular medical ward, particularly in the acute cubicle where there are critically ill patients. Some years ago, I have come across a house officer (HO) trying to palpate for the apex beat during morning ward rounds and the poor HO requested for assistance as he was unable to find the apex despite numerous attempts. Upon attending by the senior medical officer, the patient was found to have no spontaneous circulation and immediate resuscitative attempts were started. 😅

CCE.