London et al.  1and Kertai et al.  2are to be commended for their review on β blockers and outcome. As an alternative to β blockers, after introduction of α2agonists in human anesthesia,3several large-scale trials or meta-analyses suggested that α2agonists decrease myocardial ischemia/infarction or mortality after cardiovascular surgery.4–6Another meta-analysis reported that β blockers decreased cardiac death from 3.9% to 0.8% and that α2agonists decreased cardiac death from 2.3% to 1.1%.7By contrast, another point of view suggests that β blockers and α2agonists cannot carry a relative risk reduction higher than 25%.8Authors suggested that α2agonists are an alternative when asthma/hyperreactive airway,1,2,7atrioventricular block,1,2,7or decompensated systolic failure7are present. In fact, α2agonists reduce bronchoconstriction in human9and dog10models, and clonidine increases stroke index in patients with cardiac failure who have a New York Heart Association classification of III or IV11,12: The sicker the patient is, the larger the systolic performance seems to increase.13,14A recent editorial15stated that the “53% reduction in overall mortality [due to α2agonists is] actually …more impressive that was has been found in the pooled β-blocker studies.” Given the fewer contraindications of α2agonists as compared with β blockers, we surmise that clinicians could consider α2agonists as first-line  drugs. Given the recent availability of intravenous α2agonists on the North American market, administration of α2agonists is simple: oral or intravenous or down the nasogastric tube or rectally. Appropriate reduction in anesthetic doses and volume loading in coronary/hypertensive patients presenting for major cardiovascular surgery3or major noncardiac surgery have been delineated. As suggested,7,15α2agonists and β blockers should be directly compared. Conversely, they may be combined to achieve maximal favorable effects.

* Physiology, School of Life Sciences, Lyon, France, and Columbia Hospital, West Palm Beach, Florida. quintin@univ-lyon1.fr

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