Does Australia need more catheterisation laboratories to treat heart attack?

Patients receive similar treatment and have similar outcomes whether their initial hospital has cardiac catheterisation facilities or not

That early reperfusion in a cardiac catheterisation laboratory (“cath lab”) can preserve heart muscle in patients with ST‐elevation myocardial infarction (STEMI) is universally accepted,1 as captured in the “time is muscle” mantra. The reperfusion era for patients with STEMI has delivered better outcomes and reduced the number of deaths.2 Debate about whether to achieve reperfusion by lytic therapy or percutaneous coronary intervention (PCI) has also been settled, with agreement that PCI is preferable when available.3

For patients with non‐ST‐elevation acute coronary syndromes (NSTEACS), the debate is less decided.4,5 Efforts to hasten reperfusion have not had the impact expected, given the dramatic benefit for patients with STEMI.6 While the two conditions share coronary thrombus formation as their origin, their pathophysiology is fundamentally different, and requires different therapeutic targets. A consensus was reached that the benefit of early intervention in patients with NSTEACS was proportional to the risk, and a risk‐graded response was incorporated into Australian guidelines in 2016.7 It is now clear that early coronary angiography and selective PCI achieve short term benefits for patients with NSTEACS, especially when the short term risk is high, while valuable information on longer term risk is gained by assessing their coronary arteries.

Now that consensus has been reached that rapid intervention is imperative for patients with STEMI and that early intervention is recommended for those with NSTEACS, attention has turned to how best to achieve the benefits of early catheterisation. In Australia, the challenges of providing access to skilled staff and equipment for providing the best medical care to patients who experience acute coronary syndromes (ACS) in rural and remote regions are not easily overcome, and outcomes are often poorer than for patients in cities.8

In this issue of the Journal, Ayad and colleagues report their encouraging finding that patients with ACS who initially present to hospitals without cardiac catheterisation facilities receive similar treatment and have similar outcomes to those who present to cardiac catheterisation‐capable hospitals.9

To conclude from this investigation that no benefit derives from access to early catheterisation, however, would be incorrect for three reasons. First, it ignores the convincing evidence that early catheterisation is beneficial for patients with either STEMI or NSTEACS. Second, Ayad and colleagues reported that patients who actually underwent catheterisation had better outcomes than those who did not, regardless of whether they initially presented to hospitals with catheterisation capacity. Third, it overlooks the valuable advantage that knowledge of the patient’s coronary anatomy brings to planning future management of their coronary artery disease.

A more appropriate conclusion is that the Australian health system has done a remarkable job in delivering state‐of‐the‐art medical care to patients with ACS. Ayad and his colleagues noted that rates of early catheterisation have increased in recent years, irrespective of whether catheterisation is available at the hospital of initial presentation. The development of referral networks was not examined in their study, which was based on Cooperative National Registry of Acute Coronary Events (CONCORDANCE) data, but evidence for their benefit in removing barriers to early referral have been reported by other Australian authors.10

The study by Ayad and colleagues naturally has some limitations. Hospitals that did not contribute data to the CONCORDANCE registry served their communities well, but the study does not shed light on whether, where and when new cardiac catheterisation facilities would be justified. Decisions in this regard are complex and must reflect clinical need, community demand, staff training and availability, and financial sustainability. Smaller hospitals did not participate in CONCORDANCE, and we have no information about the fates of patients presenting to these hospitals — apart from the fact that, if they were lucky enough to be transferred to a catheterisation facility and underwent catheterisation, they probably fared better than those who were not transferred.