In the interchange between Stein and Flood and Kuhn’ on intraaortic balloon pumping in acute myocardial infarction, Kuhn reports a 4.2 percent incidence rate of cardiogenic shock among patients admitted to the coronary care unit of Mt. Sinai Hospital in New York City. He suggests that this rate was low in comparison with that of the community hospital described by Stein and Flood because of better therapy, which prevented cardiogenic shock. Another possible explanation is that the community hospital is presented with more seriously ill patients because of factors in patient selection. Accordingly, we surveyed admissions to the coronary care unit of Jewish Memorial Hospital in New York in order to identify the percent of patients with acute myocardial infarction who already had cardiogenic shock when they arrived in the emergency room. This institution is a community hospital of 200 beds with an active outpatient department, emergency room and intensive coronary care unit (such as specified by Stein and Flood) and receives patients through the Emergency Police Ambulance System of New York City. During 1976, a total of 107 patients with acute transmural myocardial infarction were admitted to the coronary care unit. Of this group, five patients already had cardiogenic shock when seen in the emergency room. These patients all demonstrated profound hypotension, cyanosis, cold skin and other signs and all died within a short time (3,1.5,2,10 and 48 hours, respectively). None of these patients showed serious arrhythmias at the time of shock. Our incidence rate of cardiogenie shock at entry to the coronary care unit was thus 4.7 percent, which is equivalent to the total incidence rate at Mt. Sinai Hospital. In addition, five patients experienced cardiogenic shock while in the coronary care unit and died, and two others survived. Thus, the total incidence rate was 11.2 percent. Does this finding demonstrate that coronary care units see different types of patients, perhaps depending on their geographic location and admitting procedures? We wonder whether our experience is common or unique and whether the incidence of patients who already have cardiogenic shock on arrival at the hospital is not a good index of the general severity of cases seen. Richard P. Lasser, MD

Jewish Memorial Hospital receives patients through the Police Emergency Ambulance System, some of their patients may arrive at an earlier time after infarction and thus might survive to be admitted to the coronary care unit. However, this factor probably accounts for relatively few patients because studies have shown little difference in interval between onset of chest pain and arrival at the hospital between patients who experience shock after infarction and those who do not (about 6 hours in a voluntary hospital in New York City not served by a police ambulance system). An average of about 22 hours elapsed between the presumed onset of infarction and development of shock. It is difficult to compare precisely the Mt. Sinai data with those of Lasser and Chang because the latter studied a much smaller group of patients. I am not sure that there is a statistically significant difference between the two groups. I did not compare our incidence rate of shock with that of Stein and Flood because they did not provide such information in their letter. The point I tried to emphasize was that the incidence of shock has declined in our own experience, a finding I attribute to more aggressive and effective management of pre-shock conditions that might predispose to the development of shock in some patients, such as heart failure, arrhythmias and respiratory and metabolic disorders. Unfortunately, this leaves a residual group of patients with extensive myocardial dysfunction who are, for the most part, refractory to medical management. The prognosis in patients with severe congestive heart failure without marked hypotension after acute myocardial infarction is much better than that of patients with cardiogenic shock, reasonably rigidly defined. Much of the reported efficacy of therapeutic interventions in “cardiogenic shock” may well be in this group of patients with heart failure without profound hypotension who have a more benign course with conventional management than do patients with profound hypotension. Regrettably, the patients with shock appear to be refractory to intraaortic balloon pumping and emergency revascularization surgery (unless there is surgically remediable ventricular septal defect or mitral regurgitation). I think it is clear that because of the very poor results with all forms of therapy once the shock state has occurred major efforts should be expended in identifying and classifying as to prognosis and appropriate therapy patients in a “pre-shock” group. Leslie A. Kuhn, MD, FACC Mount Sinai School of Medicine New York, New York

Hwang Nam Chang, MD Jewish Memorial Hospital New York, New York Reference 1. Slefn MF. Flood FB. Kuhn u: lnbaaatic Am J Cardiol38: 668469, 1976

balloon pumping in acute myocadiil




I agree that there may be some differences in the incidence of shock after acute myocardial infarction among different hospitals, possibly depending upon whether or not the hospital provides ambulance service. Our data were based only on patients admitted to the coronary care unit. There may well have been additional patients who were moribund on entry to the emergency room who did not survive long enough to be admitted to the unit. Because

For the past 2 l/2 years I have used a technique quite similar to that of Nadjmabadi et al.1 Most of these procedures have been performed through the right subclavian vein. I agree that this technique is generally quite safe and time-saving. However, in two patients the subclavian artery was entered with the introducing needle. Each time hemostasis was obtained by local pressure over the site of puncture. In one of these patients, it was not possible to cannulate the subclavian vein on the initial side, possibly because of displacement of the vein by hematoma. Subclavian entry was easily done from the other

March 1978

The American Journal of CARDIOLOGY Volume 41


Cardiogenic shock in the coronary care unit.

LETTERS TO THE EDITOR CARDIOGENIC SHOCK IN THE CORONARY CARE UNIT In the interchange between Stein and Flood and Kuhn’ on intraaortic balloon pumpin...
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