A major trial looking at the best drugs to treat high blood pressure has been stopped early because the results were so good.
High blood pressure can be a sign of heart disease
Experts believe this could have major implications for the treatment of millions of patients worldwide to prevent strokes and heart attacks.
The ASCOT trial found two drugs offered big advantages over an older treatment strategy in over 19,000 patients.
Patients are advised to stay on their current treatment, however.
It is dangerous to stop treatment abruptly and some patients may still be better off on the older therapy.
Most patients in the trial are now likely to be switched to the newer drugs by their doctor, however, said the researchers.
The trial started in 1997 and had not been expected to finish until 2006.
Further details about the results of the study are not yet available, but the researchers said the cardiovascular benefits of the newer treatment were "significant".
The older treatment strategy is based on the beta-blocker, atenolol and the thiazide diuretic, bendroflumethiazide.
The new treatment strategy involved two drugs - the calcium channel blocker, amlodipine, and the angiotensin converting enzyme (ACE) inhibitor, perindopril.
Professor Peter Sever from Imperial College London, who was co-chairman of the steering committee, said: "The results of the ASCOT trial have been long-awaited.
"It was really the first trial to specifically look at a combination of drugs.
"Most patients require more than one treatment so it is silly to test single drugs.
"Although we cannot give actual numbers at this stage, the results were so significant that it was important to stop a trial early because of important cardiovascular benefits to those patients receiving the newer drugs.
"The implication is that the very commonly used beta-blocker drugs are not as effective at preventing the major complications of hypertension - strokes and heart attacks and so on."
He his team will present the actual figures at a meeting of the American cardiology meeting in March.
Professor Philip Bath, a member of the executive committee of the British Hypertension Society, said the results were "potentially very exciting".
He said: "These modern drugs often cause less side-effects than older ones such as atenolol, and other trials have shown advantages with newer drugs such as perindopril.
"For example, the PROGRESS trial found that perindopril-based therapy was effective in significantly reducing vascular events in patients with a previous stroke.
"The results of ASCOT potentially open this benefit up to the very large group of
patients with hypertension around the world."