Dobutamine in acute myocardial infarction: should we use it for reduction of pulmonary hypertension and pulmonary capillary wedge pressure in acute myocardial infarction?

Introduction

Enthusiasm for application of dobutamine has retreated after the introduction to clinical practice of new medications such as levosimendan. Such treatment, however, is rather expensive as well as remote outcomes still being under discussion. Owing to this, dobutamine still has an appropriate place in the treatment of patients with complicated acute myocardial infarction (AMI) where signs of acute heart failure and pulmonary hypertension should be treated immediately. The study objective was to evaluate the hemodynamic effect of dobutamine using the pulmonary artery catheterization technique in patients with AMI complicated by cardiogenic shock and pulmonary hypertension.

Methods

Dobutamine was infused continuously for patients with AMI complicated by cardiogenic shock and with verified pulmonary hypertension. Only low doses not exceeding 4 μg/kg/min dobutamine were continuously infused. Data were obtained using a pulmonary artery catheter. Hemodynamic indices including the cardiac output (CO), pulmonary pressures and pulmonary artery capillary wedge pressure (PAWP) were measured.

Results

Nineteen patients were investigated according to the study protocol, 11 (57.9%) men and eight (42.1%) women. Average age was 65.1 ± 11.2 years. Anterior AMI was diagnosed for 14 (73.7%) patients, inferior for five (26.3%). The inhospital mortality rate was 52.6% (10 patients). The initial CO was 3.3 ± 0.9 (range from 1.8 to 5.4 l/min), the mean pulmonary artery pressure (MPAP) was 34.8 ± 13.4 mmHg (maximum 50 mmHg), and the PAWP was 25.7 ± 10.4 mmHg (maximum 42 mmHg). After the first day of continuous dobutamine infusion, the CO was 4.2 ± 1.2 (range from 2.5 to 6.4 l/min), the MPAP was 31.1 ± 7.9 mmHg (maximum 43 mmHg), and the PAWP was 16.2 ± 3.8 mmHg (maximum 21 mmHg). After the termination of dobutamine (after 48 hours), the CO was 4.2 ± 0.9 (range from 3.1 to 6.1 l/min), the MPAP was 30.2 ± 8.1 mmHg (maximum 46 mmHg), and the PAWP was 16.4 ± 3.4 mmHg (maximum 21 mmHg). The increase of the initial CO and reduction of PAWP after the first day of continuous dobutamine infusion were statistically significant (P < 0.05).

Conclusion

Application of dobutamine showed a positive benefit in reduction of pulmonary hypertension and pulmonary capillary wedge pressure as well as in the increase of cardiac output for patients with AMI complicated by cardiogenic shock and pulmonary hypertension.