Dobutamine-stress echocardiography in asymptomatic patients with aortic regurgitation.

Background: Decreased contractile reserve may already be present in asymptomatic patients with aortic regurgitation and normal ejection fraction (EF), thus indicating the need for frequent and accurate assessments of the left ventricular function for the early detection of systolic dysfunction.

Objective: To analyze if increments in EF with low dose dobutamine could predict surgery and/or death in patients with aortic regurgitation.

Methods: Dobutamine-stress echocardiography was performed in 24 patients with aortic regurgitation in order to analyze whether EF increments at low dobutamine doses could predict the need for surgery and/or death in this group of patients.

Evaluation of the marker of hypercoagulability prothrombin fragment F 1+2 in patients with mechanical or biological heart valve prostheses.

Objective: To investigate whether patients with heart valve prostheses and similar International Normalized Ratios (INR) have the same level of protection against thromboembolic events, that is, whether the anticoagulation intensity is related to the intensity of hypercoagulability suppression.

Methods: INR and plasma levels of prothrombin fragment 1+2 (F1+2) were assessed in blood samples of 27 patients (7 with mechanical heart valves and 20 with biological heart valves) and 27 blood samples from healthy donors that were not taking any medication.

Results: Increased levels of F1+2 were observed in blood samples of 5 patients with heart valve prostheses taking warfarin.