Abstract 149: Risk Prediction Early After Myocardial Infarction: Resting Respiratory Rate Is Independent of GRACE Score
Background: The GRACE Score (GS) was proposed as a risk stratification tool in acute coronary syndrome patients. The GS includes age, history of congestive heart failure and previous myocardial infarction, heart rate, systolic blood pressure and presence of ST-segment depression at admission, and serum creatinine, cardiac enzymes and percutaneous coronary intervention (PCI) during hospitalization. We hypothesized that resting respiratory rate (RRR) carries independent risk information in patients with acute myocardial infarction (AMI).
Methods: 941 consecutive AMI patients aged <=80 yrs were included. 93% underwent a PCI, 95% received beta-blockers, 94% ACE inhibitors and 93% statins. The GS was calculated according to the published protocol. In addition, RRR was assessed over a 10-minute period by means of a piezoelectric chest belt sensor (Protech, 7 ± 2 days after AMI). Follow-up was 5 years. Primary endpoint was total mortality.
Results: During follow-up, 72 patients (7.7%) died. In multivariable analysis, respiratory rate was independent from the GRACE Score (see Table). Combination of the GS and RRR revealed a larger area under the receiver-operator characteristics curve if compared to GS alone (0.74 versus 0.77, p < 0.05).
Conclusion: Resting respiratory rate is an independent risk predictor in post-AMI patients which is not taken into account in the GRACE Score.
- © 2011 by American Heart Association, Inc.