An echocardiogram should be used to confirm heart failure
Many GPs, and even some hospital specialists, are failing to follow guidelines for managing heart failure, a Europe-wide survey suggests.
British GPs frequently did not use recommended tests or drugs, which the researchers said could be unsafe.
The European Heart Journal report said the results were "very worrying".
However, one specialist GP disputed whether the survey answers were clear evidence of poor practice among family doctors in the UK.
Heart failure is a common disease of old age, with approximately 67,000 new cases diagnosed in the UK every year.
The study found that while 94% of UK hospital cardiologists would use an echocardiograph test, 69% of GPs said that they could make the diagnosis on symptoms and other signs alone.
Only half the GPs who answered the survey said they often needed other tests to confirm the diagnosis, the team led by the Sticares Cardiovascular Research Foundation in the Netherlands reported.
Only a quarter of GPs said they could get echocardiography tests for their patients within a month - compared to three quarters of French primary care doctors, 90% in Germany, and 51% in Italy.
Having made their diagnosis, just over a third of UK GPs opted for a treatment using ACE inhibitors, with well over half appearing to choose diuretic drugs alone, a practice described as "unsafe" by the study authors.
However, Dr Terry McCormack, a Yorkshire GP and chairman of the UK Primary Care Cardiovascular Society, said that European guidelines did not exactly match those in the UK, and there were reasonable arguments for using diuretics as a first step while awaiting test results.
"No-one is going to turn around and say that heart failure care in the UK is perfect, but I don't think that we are performing that badly.
"We are pretty good for getting echocardiagrams, and pretty good for the use of ACE inhibitors and beta blockers."
Among the specialists, ACE inhibitors were more commonly prescribed, with 85% of UK cardiologists saying they used them in at least nine out of 10 patients, well above the European average.
Professor Willem Remme, who led the study, said that many doctors were aware that the guidelines existed, but had not read them, or chose not to follow them.
"I find these figures very worrying as guidelines are the only source of information which gives management advice in a complete and unbiased way, based on data from controlled studies or real expert opinion."
Professor Peter Weissberg, medical director for the British Heart Foundation, said: "The main message from this study is that heart failure patients get better treatment if they are managed by a specialist."