Inducibility of Atrial Fibrillation During Electrophysiologic Evaluation is Associated with Increased Dispersion of Atrial Refractoriness

The impact of atrial dispersion of refractoriness (Disp_A) in the inducibility and maintenance of atrial fibrillation (AF) has not been fully resolved. AIM: To study the Disp_A and the vulnerability (A_Vuln) for the induction of self-limited (<60 s) and sustained episodes of AF. METHODS AND RESULTS: Forty-seven patients with paroxysmal AF (PAF): 29 patients without structural heart disease and 18 with hypertensive heart disease. Atrial effective refractory period (ERP) was assessed at five sites--right atrial appendage and low lateral right atrium, high interatrial septum, proximal and distal coronary sinus. We compared three groups: group A - AF not inducible (n=13); group B - AF inducible, self-limited (n=18); group C - AF inducible, sustained (n=16). Age, lone AF, hypertension, left atrial and left ventricular (LV) dimensions, LV systolic function, duration of AF history, atrial flutter/tachycardia, previous antiarrhythmics, and Disp_A were analysed with logistic regression to determine association with A_Vuln for AF inducibility. The ERP at different sites showed no differences among the groups. Group A had a lower Disp_A compared to group B (47+/-20 ms vs 82+/-65 ms; p=0.002), and when compared to group C (47+/-20 ms vs 80+/-55 ms; p=0.008). There was no significant difference in Disp_A between groups B and C. By means of multivariate regression analysis, the only predictor of A_Vuln was Disp_A (p=0.04). Conclusion: In patients with PAF, increased Disp_A represents an electrophysiological marker of A_Vuln. Inducibility of both self-limited and sustained episodes of AF is associated with similar values of Disp_A. These findings suggest that the maintenance of AF is influenced by additional factors.

Antibiotics Utilization Ratio in a Nicu

Introduction: Antibiotics are one of the most common prescribed drugs in the NICU; despite this, studies on its use are scarce. Aim: To assess antibiotics utilization ratio in a medical surgical NICU. Methods: Prospective, observational study. Daily registry of antibiotics given to newborn infants; two periods of two months, 2010; data collected every day after the second medical round. Variables: treated patients, days on antibiotics, treatment/patient days, number of courses, number of antibiotics. Antibiotics utilization ratio – ratio days on antibiotics/days at the NICU. Results: Patients enrolled - 113; admission days – 1722; length of stay - 15.2 days; 85 newborn infants were given antibiotics; days on antibiotics - 771; antibiotics utilization ratio – 44.8; 292 antibiotics were prescribed; 61.8% of patients were given more than two antibiotics and 15.3% had more than one course. The most frequents were gentamicin, cefotaxime, ampicillin, vancomycin and metronidazole. Conclusion: Antibiotics utilization ratio should be subject of audits and a quality criteria on NICUs evaluation.

Induced Labor– Is There an Increased Risk of Perinatal Infection?

Objectives: To assess induced labor-associated perinatal infection risk at Hospital D.Estefânia from January to June of 2010 at Hospital de D. Estefânia’s delivery rooms, reviewing the indications for inducing labor as well as the techniques used. Material and Methods: Performing an historical prospective study searching the clinical processes as well as the mother and newborn’s computer database from January to June of 2010. An exposed and an unexposed group were created; the first group comprises pregnant women and their newborns whose labor was induced. The unexposed group is constituted by newborns and pregnant women whose labor was spontaneous. Labor induction was performed using intra-vaginal prostaglandins in women who didn’t start it spontaneously; perinatal infection was defined either clinically or using blood tests. The gestational age was ≥ 37 weeks for both groups. 19 variables were studied for both groups. Results: A total of 190 mother-newborn pairs were included: 55 in the exposed group and 135 in the unexposed group. 3 cases of perinatal infection were reported, two in the exposed group and one in the unexposed group. Preliminary data resulted in a perinatal infection rate of 3.6% in the exposed group and 0.7% in the unexposed group; preliminary data suggest that the risk of perinatal infection may be increased in up to 5-fold when labor is inducted. Conclusions: A larger series of patients and a multivariable analysis using logistic regression are both necessary in order to perform a more thorough assessment of labor induction’s role in perinatal infection risk. One must also try to distinguish labor inducing- and clinical practicesrelated factors.

Carotid Intima-Media Thickness and Carotid Plaques Improves Prediction of Obstructive Angiographic Coronary Artery Disease in Women

Does carotid intima-media thickness (cIMT), a surrogate marker of cardiovascular events, have predictive incremental value over established risk factors for stable coronary artery disease (CAD)? Prospective study of 300 patients, with suspected stable CAD, admitted for an elective coronary angiography and carotid ultrasound. The CAD patients had a higher cIMT, which showed a modest predictive accuracy for CAD (area under the receiver-operating characteristic curve 0.638, 95% confidence interval 0.576-0.701, P < .001). The cIMT was an independent predictor of CAD, together with age, gender, and diabetes. C-statistic for CAD prediction by traditional risk factors was not significantly different from a model that included cIMT, carotid plaque presence, or both. However, in women, it was significantly increased by the addition of cIMT or carotid plaque presence. Although cIMT cannot be used as a sole indicator of CAD, it should be considered in the panel of investigations that is requested, particularly in women who are candidates for coronary angiography.

Transthyretin Amyloidosis: Chaperone Concentration Changes and Increased Proteolysis in the Pathway to Disease

Transthyretin amyloidosis is a conformational pathology characterized by the extracellular formation of amyloid deposits and the progressive impairment of the peripheral nervous system. Point mutations in this tetrameric plasma protein decrease its stability and are linked to disease onset and progression. Since non-mutated transthyretin also forms amyloid in systemic senile amyloidosis and some mutation bearers are asymptomatic throughout their lives, non-genetic factors must also be involved in transthyretin amyloidosis. We discovered, using a differential proteomics approach, that extracellular chaperones such as fibrinogen, clusterin, haptoglobin, alpha-1-anti-trypsin and 2-macroglobulin are overrepresented in transthyretin amyloidosis. Our data shows that a complex network of extracellular chaperones are over represented in human plasma and we speculate that they act synergistically to cope with amyloid prone proteins. Proteostasis may thus be as important as point mutations in transthyretin amyloidosis.