Carbon monoxide and heart attacks.

A study of the relationship between carbon monoxide exposure and heart attacks was conducted in Baltimore. There was no evidence of clustering of either myocardial infarction or sudden ASHD on a specific day, nor was there correlation between the number of cases per day and ambient CO levels. Postmortem HbCO levels were slightly higher in ASHD sudden deaths than in sudden deaths due to other causes. Any differences were probably primarily due to cigarette smoking. Cigarette smokers who died suddenly due to ASHD had substantially higher postmortem HbCO levels than nonsmokers. Practically all of the elevated HbCO levels could be related to cigarette smoking or specific environmental exposure. There were no differences between HbCO levels in ASHD sudden death patients and in living controls. There was also no relationship between cardiac pathologic findings and postmortem HbCO levels among patients dying suddenly of ASH.