Conservative Management of Acute Coronary Syndrome

Over the last decade, 2 basic approaches have evolved to guide the use of cardiac catheterization and coronary revascularization in patients with acute coronary syndrome (ACS). Both use risk stratification tools in an attempt to achieve the best outcome for patients. Where they differ is in the most efficient means to the goal. The “conservative” approach encompasses strategies built around the use of serial clinical evaluations and noninvasive stress tests to identify those high-risk patients who need referral to diagnostic catheterization. Several variants have been developed with associated early catheterization rates ranging from 10% (FRISC-II) to as high as 57% (TIMI-IIIB).1,2⇓ The proponents of this approach cite the advantages of not exposing lower-risk patients to potential complications of invasive diagnostic procedures or to revascularization procedures without prognostic or symptomatic benefit (the so-called “oculorevascularization reflex”). Because they use fewer expensive procedures, conservative approaches have also been regarded as more efficient economically, ie, lower cost. The “aggressive” approach is based on the belief that noninvasive methods are not sufficiently accurate to identify all patients with prognostically significant coronary lesions who require revascularization. Under the concept of “a stitch in time saves nine,” proponents of aggressive strategies have also argued that these may be more economically efficient due both to an efficient early risk stratification process that minimizes expensive hospital days occupied with “watchful waiting” and to a reduction in subsequent hospitalizations and procedures resulting from reactivated unrevascularized disease. Aggressive strategies have typically used diagnostic cardiac catheterization in over 90% of ACS patients, most often between 4 and 48 hours after presentation.See p 680 Thus, both conservative and aggressive management strategies have claimed not only a more preferable risk:benefit ratio but also important economic advantages. Four major clinical trials have compared medical outcomes for these 2 strategies.1–4⇓⇓ …