The time between arrival at hospital and reperfusion is significantly shorter for STEMI patients who arrive by ambulance than by other means. So who calls an ambulance and who doesn’t?
A research letter in The MJA reports an analysis of 2,765 patients presenting to one of 43 hospitals in the Cooperative National Registry of Acute Coronary Events (CONCORDANCE) between 2009 and 2017.
It found 58.4% of patients arrived at hospital via ambulance.
Compared to non-ambulance users, ambulance users were typically:
- older (64 v 59 years)
- had more hypertension (53% v 47%)
- had more prior MI (16% v 13%)
- had more prior AF (6% v 3%)
- had more prior stroke / TIA (6% v 3%).
Although most patients were male in both groups, the proportion of males was lower in ambulance users than non ambulance users (71% v 81%).
Interestingly, fewer patients with a family history of CHD travelled by ambulance than other means (32% v 42%).
The study found time from hospital arrival to reperfusion was faster in people who arrived by ambulance than other means – 1.2 hours v 2.1 hours for PCI and 0.6 hours v 0.8 hours for fibrinolysis.
However death and MACE outcomes were similar in both groups.
“Despite the less favourable risk profiles of patients who arrive by ambulance, their hospital outcomes are comparable with those of patients who present directly to hospital, presumably because of their more rapid access to reperfusion.”
The authors, including Professor David Brieger, said shorter times to reperfusion with ambulance travel were probably because STEMI diagnosis by ECG during their journey facilitates priming of the EDs for fibrinolysis and cath labs for PCI.
“Our finding that patients with STEMI who are older and have more comorbid conditions are more likely to call an ambulance is not novel, but does indicate that this has not changed in recent years.”
“This underscores the value of calling an ambulance when chest pain develops, and suggest that this public health message should be more actively promoted,” they concluded.