The cohort included 55 consecutive patients with first ST elevation acute myocardial infarction (STEAMI) who underwent reperfusion. Blood samples were drawn for N-terminal pro B-type natriuretic peptide (NT-proBNP), highly-sensitive C-reactive protein (hs-CRP), creatinine kinase (CK), cardiac troponin l (cTnl), and white blood cell (WBC) count within 24 hours of admission. Transthoracic echocardiography, performed within the same time frame, assessed left ventricular (LV) systolic function, as well as diastolic function. Variables significantly associated with poor systolic LV dysfunction were hs-CRP, peak CK, cTnl, and WBC. There was no significant correlation between NT-proBNP and systolic function early after STEAMI (p=0.49). Among patients with diastolic dysfunction, there was no significant correlation between NT-proBNP levels and peak mitral E-wave velocity to peak initial A-wave velocity (E/A ratio) (r =0.19, p=0.18) or E-wave deceleration time (r =0.22, p=0.15). Thus, NT-proBNP levels in the early phase after STEAMI were not indicative of systolic or diastolic function.