Specific guide to this web site for:
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4. High School & College
1. Harvard led MI study
(J. of Amer. Coll.
4. Amer. J. of Cardio.
review of literature
6. Oat bran study
7. Pregnancy & Alcohol
8. Are Geminis
9. Columbia 'Miracle' Study
Limitations of Meta-Analyses
Large Randomized Clinical
Tale of Two Large
Outpatient versus inpatient catheterization. Roehm E. NEJM 1989; 320:938
To the Editor: The article by Dr.
Block et al1 regarding outpatient versus inpatient cardiac
showed a high frequency of myocardial infarctions developing in the outpatient
group. The outpatient group developed a myocardial infarction in 1.6% of the
patients (3/192) versus 0.5% (1/189) in the inpatient group. There was no
statistical significance in this threefold difference in myocardial infarction
rate, though as the authors have suggested, this may be the result of a type II
The frequency of myocardial infarction occurring as a possible complication of
cardiac catheterization is quite low in modern day studies. The CASS study which
included patients with unstable angina in contrast to Dr. Block's study, had a
0.45% combined incidence of myocardial infarction and fatal events within 48
hours of the procedure.2 Unstable angina in the CASS study was the only variable
statistically associated with the occurrence of nonfatal infarction, and was
present in the majority of the fatalities as well. Other large modern day
studies have reported myocardial infarction as a complication in 0.09%3 and
0.07%4 of patient's undergoing cardiac catheterization. The incidence of
myocardial infarction is considerably higher in the outpatient group in Dr.
additional information on the 4 patients in Dr. Block's study who developed a
myocardial infarction would be useful. How many hours after the cardiac
catheterization did the onset of each myocardial infarction occur?
Were there factors in the individual cases that suggested the development
of the myocardial infarction was related to the outpatient protocol? What type
of coronary disease and functional class existed in each of the patients who
experienced a myocardial infarction?
of this type may help indicate whether this particular outpatient protocol
played a role in the development of the myocardial infarctions which occurred.
For example, if early mobilization led to a large hematoma associated with
hypotension followed by a myocardial infarction, this would be suggestive
evidence that the infarction was related to the outpatient catheterization
procedure. Alternatively, if the myocardial infarction occurred prior to
mobilization, it would indicate the patient's outpatient status was unrelated to
modern day study of a cardiac catheterization protocol, particularly in
clinically stable patients, in which one arm of the protocol experiences one
myocardial infarction every 64 patients warrants a close examination before
that approach can reasonably be considered both "feasible and safe".
Would the authors examine their patient data and furnish additional information
to allow for further evaluation of this aspect of their study? (The
New England Journal of Medicine Editors deleted this last paragraph of the
letter after accepting it for publication.)
P, Ockene I, Goldberg R, et al. A Prospective Randomized Trial of Outpatient
versus Inpatient Cardiac Catheterization. N Engl J Med 1988: 219: 1251-55.
Davis K, Kennedy J,
Kemp J, et al. Complications of Coronary Arteriography from the Collaborative
Study of Coronary Artery Surgery (CASS). Circulation 1979: 59: 1105-12.