A review of 33 trials has provided evidence that does not support current guidelines* for use of β-blocker therapy for prevention of adverse clinical outcomes in patients having non-cardiac surgery. The authors of this Article, which is published early Online and in an upcoming edition of The Lancet, believe these guidelines should not be further promoted until conclusive evidence is available.
Dr Sripal Bangalore, Brigham and Women's Hospital, Boston, MA, USA, and Professor Franz Messerli, St Luke's-Roosevelt Hospital and Columbia University College of Physicians and Surgeons, New York, USA, and colleagues did the meta-analysis of these 33 studies, which included 12 306 patients. They found the use of β-blockers were not associated with any significant reduction in the risk of all-cause mortality, cardiovascular mortality, or heart failure; but they did reduce the risk of non-fatal heart attack by 35% and reduce the risk of less serious heart blood vessel blockage by 64%. However, these reductions came at the expense of the doubling of risk for non-fatal stroke, with 1 in every 293 patients given β-blockers suffering a stroke of this kind. β-blockers were also associated with a high risk (1 in 22 patients) of low heart rate (bradycardia) requiring treatment, and an even higher risk (1 in 17 patients) of low blood pressure (hypotension) requiring treatment. The authors say: "The beneficial effects [of β-blockers] were driven mainly by trials with a high risk of bias."
The authors conclude: "β blockers should not be routinely used for perioperative treatment of patients undergoing non-cardiac surgery unless patients are already taking them for clinically indicated reasons**... The ACC/AHA* guideline committee should soften their stance on perioperative β blockade until definitive evidence shows clear benefit."
In an accompanying Comment, Professor Eric Boersma and Professor Don Poldermans, Erasmus Medical Center, Rotterdam, Netherlands, say that the net clinical outcome of β-blocker treatment should not be based on the sum of its effects presented in this study. But they call on all colleagues who are working on β-blocker trials to release data about clinical conditions and perioperative changes that might have resulted in the complications listed by Messerli, Bangalore and colleagues.
Dr Sripal Bangalore, Brigham and Women's Hospital, Boston, MA, USA T) +1 617 879 1702 E) SBANGALORE@PARTNERS.ORG
Professor Franz Messerli, St Luke's-Roosevelt Hospital and Columbia University College of Physicians and Surgeons, New York, USA T) +1 917-750-9747 E) fmesserl@chpnet.org
Professor Don Poldermans, Erasmus Medical Center, Rotterdam, Netherlands T) +31 6 22 37 12 76 E) d.poldermans@erasmusmc.nl / h.boersma@erasmusmc.nl
Notes to editors: * The guidelines referred to are those of the American College of Cardiology (ACA) and American Heart Association (AHA)
**clinically indicated reasons : heart failure, coronary artery disease, previous myocardial infarction
Full Article and Comment: http://press.thelancet.com/bblockersfinal.pdf
Journal
The Lancet