To evaluate whether patients who recognize the symptoms of myocardial ischemia and have easy access to medical care have shortened time delays between onset of symptoms and hospital presentation, the total time interval between symptom onset and hospital arrival for 258 U.S. male physicians experiencing a first acute myocardial infarction (AMI) in the Physicians' Health Study (PHS) was compared with that of a comparable group of 240 men enrolled in the U.S. component of the Second International Study of Infarct Survival (ISIS-2), as well as with those of previously published series of patients with AMI. For patients presenting for medical care within 24 hours of symptom onset, the median time delay from onset of symptoms to presentation for medical care was 1.8 hours in the PHS, and 4.9 hours in the U.S. component of ISIS-2 (p less than 0.001). Furthermore, 56% of participants in the PHS presented for medical care within 2 hours and 72% within 4 hours of symptom onset compared with 20% (p less than 0.001) and 44% (p less than 0.001), respectively, for ISIS-2 participants. In previously published series, the average time to presentation was comparable to that in the ISIS-2 trial, with variation depending on country of origin and on local population density. The median time to medical presentation in any previous series was not shorter than that in the PHS. Thus, physicians in the PHS had significantly shorter time delays between onset of symptoms and presentation for medical care. This difference may help explain the far lower than expected cardiovascular mortality rates among physician participants in the PHS.(ABSTRACT TRUNCATED AT 250 WORDS)