Correspondence
Adjunctive Drug Therapy for Acute Myocardial Infarction
N Engl J Med 1997; 336:1455-1456May 15, 1997
- Article
To the Editor:
The recommendation by Hennekens et al. (Nov. 28 issue)1 that beta-adrenergic–antagonist drugs be routinely administered to patients during acute myocardial infarction is supported by convincing findings from clinical trials. The evidence supporting their view that long-term beta-adrenergic–antagonist therapy is indicated is more ambiguous. Algorithms based on the extent of residual myocardial ischemia and left ventricular function after myocardial infarction can identify a low-risk subgroup of patients with well-preserved left ventricular function and no evidence of marked ischemia at rest or during symptom-limited exercise testing.2 This subgroup, which accounts for 40 to 50 percent of patients surviving a myocardial infarction, has an infarction-related mortality rate of 2 percent or less at one year.2 Beta-adrenergic–antagonist therapy is likely to be of little benefit in this subgroup.
Hennekens et al. lament that only 36 to 42 percent of patients with acute myocardial infarction who were enrolled in the National Registry of Myocardial Infarction between 1990 and 1993 received beta-adrenergic–antagonist therapy. I share their disappointment as far as the use of such therapy in the setting of acute myocardial infarction is concerned. For the reason stated above, however, I am dubious about the benefits of long-term therapy with these drugs in unselected patients after myocardial infarction. I have my own lament: less than one third of patients who have had uncomplicated myocardial infarctions undergo routine cardiac rehabilitation based on aerobic exercise.3 For the many patients at low risk after myocardial infarction, aerobic training is likely to result in more favorable overall metabolic changes (i.e., in autonomic balance, as well as lipid and glucose metabolism) and a better quality of life than long-term beta-adrenergic–antagonist therapy.4
4 ReferencesAndrew G. Bostom, M.D.
Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 021111
Hennekens CH ,Albert CM ,Godfried SL ,Gaziano JM ,Buring JE . Adjunctive drug therapy of acute myocardial infarction -- evidence from clinical trials. N Engl J Med 1996;335:1660-1667
Full Text | Web of Science | Medline2
DeBusk RF ,Blomqvist CG ,Kouchoukos NT , et al. Identification and treatment of low-risk patients after acute myocardial infarction and coronary-artery bypass graft surgery. N Engl J Med 1986;314:161-166
Full Text | Web of Science | Medline3
Cardiac Rehabilitation Guideline Panel. Cardiac rehabilitation. Clinical practice guideline no. 17. Rockville, Md.: Department of Health and Human Services, October 1995. (AHCPR publication no. 96-0672.)
4
O'Connor GT ,Buring JE ,Yusuf S , et al. An overview of randomized trials of rehabilitation with exercise after myocardial infarction. Circulation 1989;80:234-244
CrossRef | Web of Science | Medline
To the Editor:
Hennekens et al. provide much helpful information but leave some unanswered questions: Are their recommendations independent of the location of the myocardial infarction (anterior, inferior, or posterior), and are they applicable to patients who have undergone a revascularization procedure?
Mukesh Bhargava, M.D.
Anuja Sharma, M.D.
Franklin Memorial Hospital, Farmington, ME 04938To the Editor:
Why was there no mention of using inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase as adjunctive therapy in patients who have had a myocardial infarction? In two recent trials, these drugs have been proved to reduce morbidity and mortality after myocardial infarction in patients with high or average serum cholesterol concentrations.1,2
2 ReferencesJaime García de Tena, M.D.
Hospital Universitario Príncipe de Asturias, 28805 Madrid, Spain1
Randomised trial of cholesterol lowering in 4444 patients with coronary heart disease: the Scandinavian Simvastatin Survival Study (4S)
Web of Science | Medline2
Sacks FM ,Pfeffer MA ,Moye LA , et al. The effect of pravastatin on coronary events after myocardial infarction in patients with average cholesterol levels. N Engl J Med 1996;335:1001-1009
Full Text | Web of Science | Medline
Author/Editor Response
The authors reply:
To the Editor: We disagree with Dr. Bostom's statement that the evidence is ambiguous with respect to the benefits of long-term beta-adrenergic–antagonist therapy after myocardial infarction. Our recommendation to use these drugs is based on the consistently reduced mortality rates reported in individual randomized trials, as well as in meta-analyses of these trials. Dr. Bostom's concern that low-risk patients will not benefit from these drugs is not supported by the relevant analyses from either the Beta-Blocker Heart Attack Trial1 or the Norwegian Multicenter Study Group Trial,2 in which the risk reduction conferred by long-term therapy with beta-adrenergic–antagonist drugs was similar in three risk groups, including patients at low risk. Few would disagree with Dr. Bostom that aerobic training provides a benefit,3 but whether this benefit exceeds the effects of long-term beta-adrenergic–antagonist therapy in patients at low risk after myocardial infarction is not known.
Drs. Bhargava and Sharma question whether the recommendations are independent of the location of the infarct and whether they are applicable to patients who have undergone revascularization procedures. Subgroup analyses from the Beta-Blocker Heart Attack Trial1 and the Norwegian Multicenter Study Group Trial2 revealed that beta-adrenergic–antagonist drugs had similar benefits in patients with inferior myocardial infarction and those with anterior myocardial infarction. With respect to angiotensin-converting–enzyme inhibitors, the benefit is apparent regardless of the location of the infarct in patients with depressed left ventricular function.4 None of these trials provided data on whether coronary revascularization modifies the benefit of these drugs.
We agree with Dr. García de Tena that all the current evidence indicates that HMG-CoA reductase inhibitors should be considered as adjunctive drug therapy after myocardial infarction in patients who have even mildly elevated serum low-density lipoprotein cholesterol concentrations.
4 ReferencesCharles H. Hennekens, M.D.
Christine M. Albert, M.D.
Julie E. Buring, Sc.D.
Brigham and Women's Hospital, Boston, MA 02215-12041
A randomized trial of propranolol in patients with acute myocardial infarctionI. Mortality results. JAMA 1982;247:1707-1714
CrossRef | Web of Science2
The Norwegian Multicenter Study Group
Full Text | Web of Science | Medline3
O'Connor GT ,Buring JE ,Yusuf S , et al. An overview of randomized trials of rehabilitation with exercise after myocardial infarction. Circulation 1989;80:234-244
CrossRef | Web of Science | Medline4
Pfeffer MA ,Braunwald E ,Moye LA , et al. Effect of captopril on mortality and morbidity in patients with left ventricular dysfunction after myocardial dysfunction. N Engl J Med 1992;327:669-677
Full Text | Web of Science | Medline
