Exercise ECG fails to predict CV illness
By Nigel Praities
ECG is barely any better than a basic clinical assessment at providing predictive information on future risk of cardiovascular illness, report UK researchers.
The research, on patients attending chest pain clinics, suggests doctors should not be relying on ECG alone to predict prognosis.
As many as 47% of coronary events in the study occurred in patients with a normal exercise ECG,
Researchers followed over 8,000 outpatients with suspected angina presenting at rapid access chest pain clinics at six hospitals in England for two and a half years.
Those with an abnormal resting ECG had a 15% chance of coronary death or acute coronary syndrome within six years, compared with a 16% chance if they had typical chest pain picked up from a clinical examination.
Exercise ECG fared only slightly better, with a 19% chance of a major coronary event or death within six years following a positive result.
Professor Adam Timmis, professor of clinical cardiology at Bart's and The London Queen Mary's School of Medicine and Dentistry, said the results showed the importance of a full clinical examination and patient history in patients at risk of a coronary event, rather than relying on ECG results.
‘The bottom line is that for identifying people at risk of future events, ECGs don't add much. They are not useless and do provide useful information, but in the real world of patient assessment they should be used in conjunction with the easier and cheaper technique of clinical assessment,' he said.
Professor Mike Kirby, professor of health and human sciences at the University of Hertfordshire and a GP in Radlett, agreed with the researcher's conclusions.
‘When an ECG is normal it doesn't mean the coronary arteries are normal. You need to take a very careful history, because you are looking for patients with unstable symptoms,' he said.