Opposite evolution on voltage and thickness from paroxysmal to persistent AF

Background

There is a controversy about correlation between voltage and thickness in the atrial myocardium and their evolution from paroxysmal to persistent atrial fibrillation (AF).

Purpose

This is an observational study to compare voltage and thickness of different areas on the left atrium in paroxysmal and persistent atrial fibrillation.

Methods

Twenty-one patients underwent atrial fibrillation ablation. Points with electrical information from an electroanatiomical map in sinus rhythym were acquiered during the ablation procedure covering the whole atrial surface. CT was acquired in all patients before the procedure and endo- and epicardium from the atrium was segmented for the atrial thickness calculation. All the points from the electromecanical map were projected on the thickness map to have both information on the same location. 3D atrium was segmented in 5 areas for the analysis: Lateral, Anterior, Septal, Inferior-Posterior and Superior-Posterior (Figure 1). Voltage and thickness values among different areas and between AF type were compared.

Results

11 paroxysmal and 10 persistent AF patients were analyzed acquiring 452±207 points per patient and 1897±750 points per area. There was no linear correlation between voltage and thickness comparing all the patients nor among different areas nor between AF type (R<0.2 in all cases).

Regarding paroxysmal AF patients, septum showed significatly lower voltage compared with the other segments, posterior, lateral, anterior and roof (1.3±1.4, 2±1.8, 2±1.6, 1.7±1.5, 2±1.6, P<0.001). Posterior segment showed the highest voltage. The thickness analysis showed the septum segment as thinner segment and lateral as thicker segment (1.3±1.5,1.7±0.8, P<0.001) (Figure 2).

Regarding persisten AF patients: septum showed significatly lower voltage compared with the other segments, posterior, lateral, anterior and roof who shows higher voltage (1±0.8*, 1.5±1.2, 1.9±1.7, 1.5±1.4, 2±1.6) (Figure 2). The thickness analysis showed the anterior segment as thinner segment and lateral as the thickest segment (1.6±0.8, 1.9±0.9 (P<0.001), different like on paroxysmal AF population.

Comparing voltage and thicknes between paroxysmal and persistent AF, all the segments on persistent population showed lower voltage values, with significant differences on septal, posterior and anterior walls (1±0.8 vs 1.3±1.4, 1.5±1.2 vs 2±1.8, 1.5±1.4 vs 1.7±1.5, P<0.001). On the other hand, all segments on persistent population showed statisticaly signignificant thicker myocardium in camparison with paroxysmal population (Figure 2).

Conclusions

According to our findings, there is no linear correlation between voltage and thickness. Persistent AF atria show thicker walls but with lower voltages in comparison with paroxysmal AF atria.

Funding Acknowledgement

Type of funding sources: None.

Tumor infiltrating lymphocytes in acral lentiginous melanoma: a study of a large cohort of cases from Latin America

PURPOSE

Acral lentiginous melanoma (ALM) is a poor prognosis subtype and is the most prevalent in non-Caucasian populations. The presence of tumor infiltrating lymphocytes (TILs) has been associated with poor prognosis in melanoma. A large cohort of ALM cases was studied to determine status of TIL and its association with outcome.

METHODS

All patients with cutaneous melanoma presenting from 2005 to 2012 at Instituto Nacional de Enfermedades Neoplasicas in Peru were retrospectively identified. Clinicopathological information was obtained from the medical charts. A prospective evaluation of TIL was performed. Analysis of association between ALM and clinicopathological features including TIL as well as survival analysis compared the outcome of ALM to whole group and extremity NALM was performed.

RESULTS

537 ALM from a total of 824 cutaneous melanoma cases were studied. Older age (p = 0.022), higher Breslow (p = 0.008) and ulceration (p < 0.001) were found to be more frequent in ALM. Acral had worse overall survival (OS) compared with the whole group (p = 0.04). Clinical stage (CS) I-II patients had a median OS of 5.3 (95% CI 4.3-6.2) for ALM and 9.2 (95% CI 5.0-7.0) for extremity NALM (p = 0.016). Grade 0 (absence of TIL), I, II and III were found in 7.5, 34.5, 32.1, and 25.9%, respectively. Lower TIL grade was associated with larger tumor size (p = 0.003), higher Breslow (p = 0.001), higher Clark level (p = 0.007), higher CS (p = 0.002), extremity location (p = 0.048), histological subtype ALM (p = 0.024) and better OS (p = 0.001).

CONCLUSIONS

ALM is highly prevalent in Peru and carries poor outcome. Lower TIL levels were associated with poor outcome and ALM.

Association Between Time to Reperfusion and Outcome Is Primarily Driven by the Time From Imaging to Reperfusion

Background and Purpose—

A progressive decline in the odds of favorable outcome as time to reperfusion increases is well known. However, the impact of specific workflow intervals is not clear.

Methods—

We studied the mechanical thrombectomy group (n=103) of the prospective, randomized REVASCAT (Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke due to Anterior Circulation Large Vessel Occlusion Presenting Within Eight Hours of Symptom Onset) trial. We defined 3 workflow metrics: time from symptom onset to reperfusion (OTR), time from symptom onset to computed tomography, and time from computed tomography (CT) to reperfusion. Clinical characteristics, core laboratory-evaluated Alberta Stroke Program Early CT Scores (ASPECTS) and 90-day outcome data were analyzed. The effect of time on favorable outcome (modified Rankin scale, 0–2) was described via adjusted odds ratios (ORs) for every 30-minute delay.

Results—

Median admission National Institutes of Health Stroke Scale was 17.0 (14.0–20.0), reperfusion rate was 66%, and rate of favorable outcome was 43.7%. Mean (SD) workflow times were as follows: OTR: 342 (107) minute, onset to CT: 204 (93) minute, and CT to reperfusion: 138 (56) minute. Longer OTR time was associated with a reduced likelihood of good outcome (OR for 30-minute delay, 0.74; 95% confidence interval [CI], 0.59–0.93). The onset to CT time did not show a significant association with clinical outcome (OR, 0.87; 95% CI, 0.67–1.12), whereas the CT to reperfusion interval showed a negative association with favorable outcome (OR, 0.72; 95% CI, 0.54–0.95). A similar subgroup analysis according to admission ASPECTS showed this relationship for OTR time in ASPECTS<8 patients (OR, 0.56; 95% CI, 0.35–0.9) but not in ASPECTS≥8 (OR, 0.99; 95% CI, 0.68–1.44).

Conclusions—

Time to reperfusion is negatively associated with favorable outcome, being CT to reperfusion, as opposed to onset to CT, the main determinant of this association. In addition, OTR was strongly associated to outcome in patients with low ASPECTS scores but not in patients with high ASPECTS scores.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01692379.

An integrated approach to understanding the sorption mechanism of phenanthrene by cork

Previous studies have shown the high sorption affinity of polycyclic aromatic hydrocarbons by cork. The aim of the present work is to go further by investigating the sorption mechanism of polycyclic aromatic hydrocarbons (exemplified by phenanthrene) on cork and the availability of the chemical components (i.e. lignin, suberin, holocellulose and extractives) to retain phenanthrene. Two approaches were integrated to reach this objective: (1) statistical multivariate analysis to obtain correlations between the sorption capacity, measured as K(oc), and the sorbent properties (i.e. polarity, acidic functional groups, %dichloromethane extractives, %ethanol and water extractives, %suberin, %lignin and %holocellulose) and (2) modeling calculations to obtain information on interaction at the molecular level. The statistical multivariate analysis demonstrated a strong and positive correlation between K(oc) and the lignin content as well as negative correlations between K(oc) and the phenolic groups and %dichloromethane extractives contents. The modeling study showed that the lignin-phenanthrene interaction is mostly hydrophobic in nature being largely determined by the π-stacking interaction between the aromatic groups of the interacting partners. This result justifies the observed correlations as dichloromethane extractives, being hydrophobic, compete with phenanthrene adsorption, whereas phenolic groups, as well as negatively charged groups, enhance the hydrophilic character of the sorbent surface, thus hindering the adsorption of phenanthrene.

A Randomized Trial Comparing Two Corticosteroid Regimens Combined With Mycophenolate Mofetil and Cyclosporine for Prevention of Acute Renal Allograft Rejection

INTRODUCTION

The launching of mycophenolate mofetil (MMF) has reduced the incidence of acute rejection episodes. We sought to evaluate the efficacy of decreasing the steroid dose.

MATERIALS AND METHODS

This was a quasiexperimental, randomized, prospective trial. We enrolled 150 patients who received de novo renal transplantations from living or cadaveric donors, fulfilling the screening criteria. Patients were randomized to one of the following two arms: (A) MMF at a 2 g/d dose, cyclosporine (CsA) at a dose necessary to achieve target levels, and corticosteroids at the usual doses; (B) MMF at a 2 g/d dose, CsA at a dose necessary to achieve target levels, and corticosteroids at doses 50% lower than those of group A.

RESULTS

Group A included 72 (48%) and group B, 78 patients (52%). There were no differences among the variables: leukopenia occurred in 11 patients in group A, and five patients in group B. Complications occurred in 67.4% (56) of group A, but only 32.6% (27) were related to infections. One case of urinary infection occurred in group B, while six occurred in group A. There was one case of acute rejection in group A, and none in group B. One graft loss occurred in group A. There were no differences in the remaining variables under study.

DISCUSSION

The results showed an increased complication rate related to receiving usual steroid doses. There was no increase in acute rejection episodes among patients receiving 50% of the usual steroid dose.

[Evaluation of the anatomopathological characteristics and the safety of radiofrequency lesions at the atrial level with two different systems of irrigated tip catheters on an experimental level]

INTRODUCTION AND OBJECTIVES

We performed this study to evaluate the security and efficacy in the lesions produced on the atrial wall by different irrigated catheters in an experimental model. We evaluated the anatomopathologic characteristics of the lesions produced by two different systems of irrigated tip catheters, with opened or closed circuit.

METHODS

This study was performed in 16 pigs applying 60 sec radiofrequency pulses with three different energy levels (15, 25 y 50 Watts). Two different systems of radiofrequency ablation irrigated catheters were used, opened and closed. We used 4 pigs in which we performed ablation with a standard catheter as a control group. Under fluoroscopic guidance, catheters were placed on the high and low right atrial lateral wall, where lesions were produced. After 7 days, animals were sacrificed for anatomopathological study.

RESULTS

A total of 27 lesions were performed with irrigated catheters (11 closed circuit and 16 opened) and 6 with standard catheters in the control group. We did not find significant differences in the lesion characteristics between the two different systems of irrigated tip catheter used, nevertheless lesions performed with the closed system were slightly greater. Th lesions produced with irrigated catheters were always superior in the control group. Transmurality in the free atrial wall is frequent with both systems. We did not see any perforation in the atrial wall.

CONCLUSIONS

We did not find significant differences in the size of the lesions produced with the two systems of irrigated catheters used. These data from an experimental model can provide useful information for atrial tachycardia radiofrequency ablation procedures in humans.

[Meningococcal disease in Spain: seasonal nature and recent changes]

BACKGROUND

In this study we built a time series model in the time domain based on the cases of meningococcal disease declared every four weeks in Spain between 1972 and 1998 With the model we analyzed the incidence of the disease and examined whether an epidemic really took place at the beginning of 1997, or whether the values were in the range of expectations. At this time there was widespread social alarm in Spain, because there was considered to be an outbreak of meningitis. We also examined whether the incidence of the disease diminished during 1997 following the measures introduced by the Comisión Interterritorial del Sistema Nacional de Salud.

METHOD

The data on the incidence of the meningococcal disease in Spain were obtained from the Boletín Epidemiológico Semanal, published by the Instituto de Salud Carlos III, declared from 1972 to 1998 and grouped every four weeks. The method corresponds to the time series model in the domain of time: the Box-Jenkins method.

RESULTS

In order to explain the behaviour of the disease during the years of the study we chose a model ARIMA(0,1,1) (0,1,1)13 that shows annual seasonal behaviour, with higher incidence in the winter and the beginning of spring, and lower incidence in summer. An intervention analysis showed that in March 1996 there was a level shift in the incidence of the illness. This lasted until September 1997, at which time the incidence returned to pre-1996.

CONCLUSIONS

The measures of sanitary monitoring against the meningitis in the months of greater incidence, winter and beginning of spring must be intensified. Between spring 1996 and autumn 1997 the incidence of meningitis increased. Thereafter, until the end of 1998, there was a significant decrease in incidence, attributable to the performance of the health authorities.

[Churg-Strauss syndrome with pericardial and myocardial involvement]

We report the case of a 63-year-old female diagnosed with Churg-Strauss syndrome with both pericardial tamponade and myocardial involvement with congestive heart failure. Allergic granulomatosis and angiitis (Churg-Strauss syndrome) is classically characterized by hypereosinophilia and systemic necrotizing vasculitis of medium and small arteries in patients with previous allergic rhinitis or bronchial asthma. Subsequently the disease has been shown to be associated with cardiac involvement and is responsible for higher morbidity and mortality. The literature for Churg-Strauss syndrome of the heart is reviewed and recent advances in the clinical management of the disease according to appropriate therapeutic strategies are recommended.

The effect of indomethacin on the pulsatility index of the umbilical artery in human fetuses

Pulsed and continuous-wave Doppler ultrasonography was used to assess blood velocities in the ductus arteriosus and the pulsatility index of the umbilical artery in 20 fetuses (1 pair of twins and 18 singletons) at 23 to 33 weeks' gestation during maternal indomethacin therapy for preterm labor or polyhydramnios. There was no statistically significant difference in the pulsatility index of the umbilical artery during maternal indomethacin treatment (mean +/- SD, 1.11 +/- 0.20) when compared with baseline values (1.12 +/- 0.19) in all 20 fetuses studied. An increase in the peak systolic and diastolic blood velocities in the ductus arteriosus consistent with ductal constriction was noted in 9 fetuses. Analysis of the umbilical artery pulsatility index values before and during indomethacin in this subgroup of fetuses failed to reveal a statistically significant change (1.12 +/- 0.19 vs. 1.11 +/- 0.20). Indomethacin therapy does not influence the pulsatility index of the umbilical artery at the gestational ages studied.

Percutaneous umbilical cord blood sampling in the evaluation of fetal platelet counts in pregnant patients with autoimmune thrombocytopenia purpura

Autoimmune thrombocytopenia purpura in pregnancy is associated with fetal thrombocytopenia. Twenty-one patients with autoimmune thrombocytopenia purpura (22 fetuses) underwent 26 umbilical cord punctures to assess the fetal platelet count. Blood could not be obtained from one fetus. Thrombocytopenia (less than 150,000/microL) was found in five cases, but in none was it of sufficient degree to preclude vaginal delivery. Persistent fetal bradycardia necessitating emergency cesarean delivery occurred in two cases. Umbilical cord puncture was found to be technically more difficult in the term fetus than in the second-trimester fetus studied in previous investigations.

Indomethacin in the treatment of premature labor. Effects on the fetal ductus arteriosus

Indomethacin is a potent agent in the treatment of premature labor, but its use has been limited because of concern about its constrictive effects on the fetal ductus arteriosus. To study these effects we used serial fetal echocardiography in 13 pregnant women in premature labor who received indomethacin according to three different dose schedules, ranging from 100 to 175 mg per day, for a maximum of 72 hours. The gestational ages of the fetuses ranged from 26.5 to 31.0 weeks. The detection of ductal constriction in 7 of the 14 fetuses by echocardiography led to the discontinuation of indomethacin. Three fetuses also had tricuspid regurgitation. There was no statistically significant difference between the mean (+/- SEM) gestational age of the fetuses with ductal constriction and that of those without constriction (29.3 +/- 0.59 and 28.4 +/- 0.52, respectively). There was no relation between serum indomethacin levels in the mothers and ductal constriction. In all seven fetuses affected, ductal constriction had resolved by the time they were restudied 24 hours after the discontinuation of indomethacin. Persistent fetal circulation was not detected in any of the 11 neonates studied after delivery. Indomethacin used to treat premature labor appears to cause transient constriction of the ductus arteriosus in some fetuses, even after short-term use.

Gastric emptying of solid and liquid meals in healthy young subjects

Gastric emptying was measured in 50 young healthy subjects by means of sequential scintigraphy with two radioactive markers. Gastric emptying of the solid component of the meal was slower than that of the liquid component, corresponding to a linear model (T 1/2, 112 min). Gastric emptying of the liquid component was different, following an exponential model, although only after 45 min (100% of the liquid marker retained in the stomach after 15 min, 56.7% after 45 min, 43.3% after 75 min, and 35.5% after 105 min). Significant differences were found in gastric emptying of both solids and liquids among sexes; women emptied the stomach more slowly than men regardless of age, weight, height, or body surface. A relationship was found between gastric emptying and the phase of the menstrual cycle. Furthermore, a quicker emptying of the liquid component was observed in smokers. These factors should be considered in the evaluation of gastric emptying studies.