RESUMO
We describe two women with interventricular septal rupture secondary to a myocardial infarction due to a total obstruction of the anterior descendent coronary artery. With the aim to stabilize the hemodynamic state of the patients before the surgical closure of the defect, we inserted a balloon-catheter introducing it to the left ventricle from the aorta and inflating it in the right ventricle after passing it through the septal orifice. After occlusion, we observed decreases in the pulmonary to systemic blood flow ratio (6% in one patient and 26% in the other) and in the arteriovenous blood flow shunt (8 and 31%); a 10% systemic blood flow increase was observed in one patient. Since the pulmonary arterial pressure did not change and the pulmonary blood flow increased, an increase of the pulmonary arterial resistance was observed but no modification of the pulmonary and systemic arterial pressure occurred. In the following days, the oxymetric differences between the pulmonary artery and the right atrium showed a tendency to remain below the figures before occlusion and the pulmonary blood flow and pressure showed a tendency to decrease. One patient died 14 days after the surgical closure of the rupture, and the other, seven days after the balloon occlusion of the rupture before any surgery. We present the physiological evolution of the patients.