Lee S, Miller R, Lee M, White H, Kerr A. Outcomes after ST-elevation myocardial infarction presentation to hospitals with or without a routine primary percutaneous coronary intervention service (ANZACS-QI 46). The New Zealand Medical Journal. 2020 Oct 30;133(1524):64-81.
Commentary from Associate Professor Garry Nixon
Why no difference? There should be a difference!
As expected STEMI patients who present to rural and provincial hospitals are older, more likely to be Māori and have on average lower socioeconomic status (because our patient populations are). They also get fibrinolytics – a second rate substitute for primary PCI. You’d expect, even with the best will in the world, that there would a measurable difference in outcomes, with patients presenting to urban PCI centres doing better . That this study failed to demonstrate this is, to say the least, surprising.
The authors attribute this to the adoption of the pharmaco-invasive strategy and the implementation of current strategies including the out-of-hospital STEMI pathway (which includes the ‘appropriate bypass of non-intervention hospitals’). But the study period (2011-2016) predates the NZ out-of-hospital STEMI pathway and we were practicing a Rescue PCI strategy targeted at patients who failed to reperfuse back then. This is evidenced by the small percentage of rural patients getting angiography within 24 hours (about 25%; a pharmacoinvasive strategy = PCI within 24hrs of fibrinolysis). And these results are not the result of hospital bypass, the basis of the study groups was hospital of initial contact. The results are however a lot better than studies done in the 1990s that demonstrated much poorer outcomes for provincial AMI patients. My guess is the key here is good communication between peripheral centres and base hospital cardiology units, and that was becoming well established by 2011 in NZ; and all parties should aim to keep building these networks.
I have to thank the whole ANZACS QI team. Its great to see a major NZ research unit looking seriously at rural outcomes. In large part that’s due to the work of the 2nd author. Well done to him.
AIM: Primary percutaneous coronary intervention (PCI) is the optimal reperfusion strategy to manage ST-elevation myocardial infarction (STEMI). Where timely primary PCI cannot be achieved, an initial pharmacological reperfusion strategy is recommended with subsequent transfer to a PCI-capable hospital. The study aim was to assess STEMI outcomes according to the interventional capability of the New Zealand hospital to which patients initially present.
METHODS: Nine thousand four hundred and eighty-eight New Zealand patients, aged 20–79 years, admitted with STEMI to a public hospital were identified. Patients were categorised into three groups— metropolitan hospitals with all-hours access to primary PCI (routine primary PCI cohort), metropolitan hospitals without routine access to PCI, and rural hospitals. The primary outcome was all-cause mortality. Secondary outcomes were major adverse cardiac events (MACE) and major bleeding.
RESULTS: Invasive coronary angiography was more frequent in the routine primary PCI cohort compared to metropolitan hospitals without routine access to PCI and rural hospitals (90.6 vs 83.0 vs 85.0% respectively; p<0.001) and occurred more commonly on the day of admission (78.9 vs 28.7 vs 25.7% respectively; p<0.001). There were no differences in multivariable adjusted all-cause mortality, MACE or major bleeding between patients admitted to any of the hospital groupings.
CONCLUSION: Outcomes after STEMI in New Zealand are similar regardless of the interventional capability of the hospital where they first present.