Comparative efficacy of the maze procedure for restoration of atrial contraction in patients with and without giant left atrium associated with mitral valve disease.

OBJECTIVES: We sought to determine the effectiveness of the maze procedure for restoring atrial contraction in patients with and without giant left atrium (GLA). BACKGROUND: Although the maze procedure has been reported to be effective for refractory atrial fibrillation, it is unknown whether this procedure can restore effective atrial contraction in patients with GLA. METHODS: Nineteen patients with and 32 patients without GLA were studied with Doppler echocardiography before and after the maze procedure. Peak velocity and the time-velocity integral of the left ventricular diastolic filling wave during atrial contraction (A wave) and the atrial filling fraction calculated as the ratio of the time-velocity integral of the A wave to that of total diastolic filling were compared between patients with and without GLA. A peak A wave velocity > or =10 cm/s was considered to indicate echocardiographic evidence of effective atrial contraction. RESULTS: Regular rhythm with P waves was restored in 10 patients (53%) with and 26 (81%, p < 0.05) without GLA. Four patients (21%) with and 21 patients (66%, p < 0.01) without GLA showed effective atrial contraction by echocardiography. Once atrial contraction was resumed, the degree of atrial contraction was comparable between patients with and without GLA (17+/-5% vs. 17+/-4% for atrial filling fraction at 12 months, respectively). CONCLUSIONS: Although most patients without GLA had restored atrial contraction by the maze procedure, it was resumed in fewer patients with GLA. However, once atrial contraction was resumed, the degree of atrial contraction was comparable between patients with and without GLA. Therefore, the maze procedure may be an option in selected patients with GLA.

[Prospective randomized study on effect of duration of antimicrobial prophylaxis for mastectomy].

A prospective randomized trial was done to study effects of the duration of ofloxacin (OFLX) administration for prophylaxis against mastectomy wound infections. One hundred and seventeen women who were hospitalized, during periods between June 1990 and September 1992 were considered for enrollment in this study. Selected patients were treated with 600 mg of OFLX daily in 3 divided doses starting the day before surgery. One group was treated for 5 days and the other was treated for 10 days. A hundred and ten patients were found eligible to complete the study and 58 patients were assigned to the 5-day group and 52 patients were assigned to the 10-day group by the random-envelope method. Nine episodes of infections occurred among the patients in the 5-day group and 12 episodes of infections occurred among those in the 10-day group. The mean time until onset of infection was not significantly different between the 2 groups (12 versus 8 days). The number of strains isolated from the drainage tube when removed was highly correlated with occurrences of infections, and the number of strains isolated from infected wounds was also highly correlated with the need to use a different antibiotic. By multiple regression analysis, age was the only significant factor identified for wound infection. The duration of OFLX administration had no significant effect on the development of wound infections. Prolonged prophylactic use of this drug for mastectomy did not reduce the incidence of postoperative infections in this study.

[Human heart recovery during weaning from a left ventricular assist system: time course and outcome prediction].

To investigate the time course of recovery of a failing heart using the left ventricular assist system (LVAS) and to predict the outcome of weaning from the LVAS, 14 patients with a failing heart were studied. Among them, 5 had recovered and survived for more than 2 weeks after weaning from the LVAS (recovered group), while 9 could not be weaned or died within 2 weeks after weaning (unrecovered group). All patients were gradually weaned from the LVAS with adequate support for systemic circulation for 3 days. In the recovered group, indices of systolic time intervals (STIs) showed improvement within a week. However, improvement of STIs was slow reaching a plateau around the 10th day in the unrecovered group. On weaning from the LVAS, aortic systolic pressure and ejection time were regulated by the patients' own hearts and were nearly the same between the 2 groups. However, left atrial pressure was significantly higher in the unrecovered group than in the recovered group. These hemodynamic features were first present on the 7th day. Therefore, hemodynamic data on the 7th assistant day can be a reliable factor in predicting the possibility of successful weaning from the LVAS and recovery in patients with a failing heart.