Physical Examination

The history will have established whether a patient’s chest pain is ischaemic in nature and likely to be related to an ACS, or whether it is pleuritic or atypical in nature, and unlikely to be related to an ACS. Examination findings will further refine the differential diagnosis generated from the history.

Physical findings associated with ACS are generally non-specific and include pallor, anxiety, sweating, tachycardia and tachypnoea.
Generally, specific physical findings are associated with other (non-ischaemic) causes for chest pain or are associated with the complications of AMI: for example, a third heart sound occurring in heart failure, a pan-systolic murmur from mitral valve regurgitation, hypotension related to cardiogenic shock, or pulmonary crepitations secondary to left ventricular failure. These physical findings make AMI more likely [17-20].

Table 6: Value of specific components of the physical examination for the diagnosis of acute myocardial infarction(19-21)

Examination finding Likelihood ratio
Ref12 Ref13 Ref14**
Increased likelihood of AMI:
    Third heart sound 3.2 3.2
    Hypotension (systolic BP <80 mmHg) 3.1 2.1 0.98-15
    Pulmonary crepitations 52.1 2.1 1.0-4.0
Decreased likelihood of AMI:
    Chest pain reproducible by palpation 0.3 0.2-0.4* 0.14-0.54*

Learning Bite

The finding of a third heart sound, hypotension or pulmonary crepitations makes AMI more likely.