A third of stroke patients are receiving inadequate care, according to a national audit.
Less than half of patients admitted to hospital having suffered a stroke are given brain scans within the first 24 hours.
Failings have been put down, to an extent, to a postcode lottery in care delivery, with Wales ranking last.
Just 24 per cent of Welsh stroke patients receive care in a stroke unit compared to 64 per cent in England and 73 per cent in Northern Ireland.
The audit recognised improvements in care at some hospitals, while other service providers are accused of failing to realise that stroke patients require "21st century care".
Dr Tony Rudd, chair of the Intercollegiate Stroke Network, said: "Not to have done [brain] imaging by 24 hours is not really good enough. We need to differentiate between bleeds and blocked arteries.
"The failure of the majority of hospitals in Wales to offer stroke unit care is scandalous and needs urgent action," reports the BBC.
Medical professionals have called for a national stroke strategy to ensure care is delivered effectively and fairly across the UK.