Abstract:

[Abstract] Objective  To evaluate the impact of different doses of recombinant human B-type natriuretic peptid (rhBNP) within the dosage of clinical rage on oxygen consumption during acute myocardial infarction (AMI) with heart failure (HF). Methods  AMI-HF model of York pig was established by occluding coronary artery with balloon combined with injecting microthrombus. Then animals were randomized into rhBNP group and control group. Clinical dose of rhBNP (1.5 μg kg bolus followed by a continuous infusion with speed of 0.01, 0.02 and 0.03 μg·kg-1·min-1 for 60 minutes respectively in turn) was administrated in rhBNP group while equal volume of saline was given in the control group. Myocardial oxygen uptake (MOU) was measured by drawing blood from coronary artery and coronary sinus using a catheter. Coronary diameter was determined using quantitative coronary angiography. The observation points were at baseline (T0), instant after the model establishment (T1), 60 min after continuous rhBNP infusion of 0.01, 0.02, 0.03 μg·kg-1·min-1 (T2-T4) respectively. Results  Compared with the control group, pulmonary capillary wedge pressure, central venous pressure, heart rate, systolic blood pressure and MOU were significantly decreased after rhBNP administration. And cardiac output and coronary diameter were obviously increased with addition of rhBNP. There is a interaction of drug intervention and time. In rhBNP group, MOU was significantly decreased with drug administraion (T2-T4 vs T1，mL O2/L: 10.61±0.35，9.85±0.60，9.79±0.31 vs 11.59±0.37). Conclusion  Intravenous administration of rhBNP in AMI-HF model could decrease MOU and PCWP while increase the cardiac output.

Key words: heart failure, myocardial infarction, recombinant human B-type natriuretic peptid, myocardial oxygen uptake