To the Editor.
—We read with interest the article by Dr Guest and colleagues1 documenting the presence of myocardial injury in critically ill patients. Cardiovascular dysfunction has long been recognized in critically ill patients. Parker et al2 clearly demonstrated left ventricular dysfunction in patients with septic shock in an ICU setting. It is not surprising that critically ill patients demonstrate biochemical evidence of myocardial injury, as evidenced by cardiac troponin I release as reported by Guest et al, given the high prevalence of multiorgan dysfunction among patients with critical illness. However, we take exception with the supposition of the authors that cardiac troponin I release among critically ill patients is necessarily related to ischemia. Despite considerable evidence of myocardial dysfunction, Cunnion et al3 have demonstrated that among patients with septic shock, myocardial perfusion is actually increased and that there is net lactic utilization across the coronary bed. Although some
Fromm RE, Varon J. Myocardial Injury in Critically III Patients. JAMA. 1995;274(21):1672. doi:10.1001/jama.1995.03530210026016