Study of Prognostic Role of High Sensitivity C - Reactive Protein and Serum Fibrinogen Levels in Unstable Angina Patients in Eastern India

Introduction: Patients with unstable angina are heterogeneous in terms of risk of cardiac death and nonfatal ischemic events. Assessment of the prognosis in these individuals guides the management protocol. C - reactive protein (CRP) and serum fibrinogen are established prognostic markers in UA. Aim: This study assessed the prognostic role of high sensitivity CRP (hs CRP) and serum fibrinogen levels in unstable angina patients in eastern India with no other high risk factors. Material and methods: It was a prospective single centre observational study which included patients admitted with diagnosis of unstable angina in medical ICU from August 1, 2009 to June 1, 2011. Cases with concomitant inflammatory or neoplastic condition, valvular heart disease, left ventricular (LV) failure, ST elevation/ new or presumably new ST depression and T wave inversion in ECG, elevated cardiac biomarkers (CPK MB/ Troponin T), LV dysfunction (LVEF<50%), suspected pulmonary thrombo embolism, age>60 years, known case of coronary artery disease, heart failure, diabetes, hypertension, dyslipidemia and chronic kidney disease were excluded from the study. Patients were observed for 72 hours in medical ICU. Serum fibrinogen and high sensitivity C - reactive protein (hs CRP) levels were estimated at the time of admission, and at the end of 48 hours and 72 hours. Primary endpoints were death, myocardial infarction, heart failure and secondary endpoints were hemodynamically unstable ventricular arrhythmias, and refractory angina or recurrent angina. Patients who met the study endpoints were grouped as unfavourable group and others as favourable group. Results: Of 1034 patients with unstable angina, 927 met the exclusion criteria and 7 were lost on follow up. On follow up, 30 (30%) patients were in unfavourable group and 70(70%) were in favourable group. Primary endpoints were met in 9% patients, death- 1(1%), myocardial infarction- 3 (3%), heart failure- 5 (5%). Secondary endpoints were met in 21% patients, ventricular arrhythmias- 4 (4%), refractory angina- 17 (17%). Patients in recurrent angina 10 (10%). Patients in unfavourable group had significantly high hs CRP (4.47±1.22 mg/L vs 1.98±0.37 mg/L, p<0.0001) and serum fibrinogen(600.93 ±49.94 mg/dl vs 404.1 ±94.01mg/dl, p<0.0001) levels at the time of admission. Patients with hsCRP levels <1mg/L or serum fibrinogen ≤500mg/dl at the time of admission had favourable outcome while those with hsCRP>3 mg/L or serum fibrinogen > 600mg/dl had unfavourable outcome. 16.67% of patients with hs CRP between 1 to3mg/L and 40% with serum fibrinogen between 501 to 600 mg/dl had unfavourable outcome. Among these patients, those with unfavourable outcome showed increasing trend of hsCRP and serum fibrinogen, so that by the end of 72 hours, they had hsCRP level >3mg/L and serum fibrinogen level >600mg/dl. Conclusion: High sensitivity C - reactive protein and serum fibrinogen levels at admission were independent prognostic markers of adverse hospital outcome in unstable angina patients. These markers can be useful in risk stratification of patients with unstable angina and early referral to cardiac care centre for destination curative therapy.