title: Prognosis after hospitalization for acute myocardial infarction not accompanied by typical ischemic chest pain. The Multicenter Diltiazem Postinfarction Trial Research Group.
abstract: OBJECTIVE
  Although ischemic-type chest pain generally identifies acute myocardial infarction (AMI), some patients are hospitalized for AMI without this symptom. Long-term mortality and morbidity after AMI presenting with alternative warning symptoms have not been examined previously. We therefore assessed the prognostic implications of the absence of typical chest pain as well as other recognized risk predictors in patients hospitalized with AMI.
  
  
  METHODS
  Data were obtained during the Multicenter Diltiazem Postinfarction Trial. Pain status and other baseline characteristics were determined prospectively by study coordinators according to simple, prespecified criteria. Patients were then examined every 3 to 4 months until trial completion. We applied chi-square methods, life-table analysis, and multivariate analysis to assess the strength and independence of prognostic power associated with each baseline variable.
  
  
  RESULTS
  Of 2,464 patients enrolled 3 to 15 days after enzyme-documented AMI, 115 patients lacked typical ischemic-type chest in on presentation (the "nonpainful" group). After 25 months' mean follow-up, cardiac mortality was 20% for nonpainful patients and 10% for 2,349 patients with typical pain (the "painful" group), P < 0.001. Similar increments were seen in total deaths (27% nonpainful versus 13% painful, P < 0.001) and cardiac events, namely, cardiac death or nonfatal reinfarction (24% nonpainful versus 17% painful, P = 0.001). Late congestive heart failure was more frequent (17% nonpainful versus 7% painful, P < 0.001), but unstable angina was less (6% nonpainful versus 16% painful, P = 0.005). At outset, nonpainful patients had more left ventricular dysfunction and diabetes mellitus. However, nonpainful AMI predicted worse outcome even when these problems were absent. Logistic regression confirmed greater cardiac death risk in the nonpainful group (hazard ratio = 2.05) and showed that predictive power of nonpainful status was independent of baseline ejection fraction, Holter data, concomitant diabetes mellitus, and other covariates.
  
  
  CONCLUSIONS
  Patients hospitalized with nonpainful AMI are much more likely to experience late cardiac death or congestive heart failure than are patients with painful AMI. In part, this probably reflects more ventricular damage with alternative warning symptoms such as dyspnea. However, our data suggest that defective perception of warning pain also provides a long-term risk to life that is independent of previously known predictors of poor outcome.
authors.affiliation: Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814-4799, USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Goldstein
authors.forename: S J
authors.initials: SJ
authors.lastname: Boccuzzi
authors.forename: D
authors.initials: D
authors.lastname: Cruess
mesh_terms: D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000209:etiology; D016009:Chi-Square Distribution; D005260:Female; D006760:Hospitalization; D006801:Humans; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis* / Q000401:mortality; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies