Urinary fibrinopeptide A levels in ischemic heart disease

Abstract

Because acute coronary thrombosis can cause unstable coronary artery disease, fibrinopeptide A, a reliable marker of coagulation activity, may play a role in the evaluation of unstable Ischemic syndromes. A new method of fibrinopeptide A sampling, spot urine normalized to urinary creatinine, was evaluated in patients with stable and unstable angina pectoris and acute myocardial infarction. Serial samples were obtained to characterize the changes in urinary fibrinopeptide A levels over time in patients with Ischemic heart disease.Admission values (meanSD) were similar in the control group (3.3 ± 1.4 ng/mg creatinine) and the stable angina group (3.2 ± 1.1 ng/mg creatinine) (p = NS). Values in the unstable angina group (5.7 ± 2.6 ng/mg creatinine) were higher than those in the control (p = 0.008) and stable angina (p < 0.001) groups. Myocardial infarction admission values (8.4 ± 10.0 ng/mg creatinine) were higher than those in the control (p = 0.005) and stable angina (p < 0.001) groups, but not higher than those in the unstable angina group. Peak values (the highest of multiple samples) were higher in the unstable angina group (7.6 ± 5.9 ng/mg creatinine) than in the stable angina group (4.0 ± 1.0 ng/mg creatinine) (p = 0.04), but not in the control group (4.5 ± 1.9 ng/mg creatinine) (p = 0.056). The two patients with unstable angina with the highest peak values subsequently exhibited infarction. Peak values in patients with infarction (44.5 ± 60.0 ng/mg creatinine) were significantly higher than those in patients with unstable (p = 0.03) or stable (p = 0.002) angina and control patients (p < 0.001). urinary fibrinopeptide A levels were elevated in 10 (48%) of 21 unstable angina admission samples, 10 (53%) of 19 unstable angina peak samples, 6 (50%) of 12 myocardial infarction admission samples and 10 (91%) of 11 infarction peak samples. No patient with stable angina had an elevated urinary fibrinopeptide A value, and 2 of 12 control patients had a slightly elevated peak value.This study shows that spot urine fibrinopeptide A levels are elevated in virtually all patients with myocardial infarction and approximately half of the patients with unstable angina. Serial sampling demonstrates dynamic changes in fibrinopeptide A levels in patients with myocardial infarction, reflecting dynamic thrombin activity. Patients with unstable angina whose condition progresses to myocardial infarction have been shown to exhibit a similar dynamic tendency. Serial spot urinary fibrinopeptide A sampling, an easy method of sample acquisition, may be helpful in identifying those patients with unstable angina who have symptoms due to intracoronary artery thrombus formation and who are at the greatest risk of progressing to myocardial infarction.