Does off-pump coronary artery bypass reduce the incidence of post-operative atrial fibrillation? A question revisited.

Atrial fibrillation (AF) is the most common post-operative complication in patients undergoing coronary artery bypass grafting, with an increased incidence associated with advancing age. This study aims to determine whether off-pump coronary artery bypass (OPCAB) reduces the incidence of AF in a generalized population (mean age <70 years). A meta-analysis was performed including all randomised and propensity score matched non-randomised studies published between 2001 and 2003 reporting a comparison between the two techniques in a generalised patient group (average age <70 years). The primary outcome of interest was post-operative AF. Sensitivity analysis was performed to evaluate consistency of the calculated treatment effect. Fourteen studies fulfilled our inclusion criteria, including a total of 16,505 subjects. The incidence of AF was 19% (1612/8265) in the off-pump group versus 24% (1976/8240) in the on-pump group. When considering only the 11 randomised studies (2207 subjects), we found a significant reduction in the incidence of post-operative AF in the off-pump group using a random-effect model (odds ratio (OR)=0.60, 95% confidence interval (CI)=0.45-0.82, and chi-square of heterogeneity=18.02, P=0.05). Sensitivity analysis highlighted one randomised study causing funnel plot asymmetry, exclusion of which resulted in a significant reduction in the incidence of post-operative AF in the off-pump group (OR=0.71, 95% CI=0.57-0.90), with a non-significant heterogeneity of 3.91 (P=0.92). When only studies of high quality were considered (898 patients), no significant difference was seen between on and off-pump groups (OR=0.78, 95% CI=0.57-1.07, and heterogeneity=0.53, P=0.91). This may be due to small number of patients in this group. Our results suggest that although OPCAB surgery may reduce the incidence of post-operative AF in a generalised population (age <70 years) this finding is not clearly supported by high quality randomised trials. Although previous evidence suggests that the incidence of post-operative AF is reduced in an elderly population (>70 years) with off-pump surgery, our results show that the evidence is less clear in a younger population group. The question of whether off-pump surgery in this patient group results in a lower rate of post-operative AF remains to be answered by further high quality randomised research.     

Disease activity in systemic lupus erythematosus: report of the Consensus Study Group of the European Workshop for Rheumatology Research. III. Development of a computerised clinical chart and its application to the comparison of different indices of disease activity. The European Consensus Study Group for Disease Activity in SLE.

In the first phase of this study, a data-base containing clinical and laboratory findings of 704 patients with systemic lupus erythematosus (SLE), originating from 29 centres and 14 countries, was used to assess the validity of 4 common indices of disease activity, SLAM, BILAG, SLEDAI and SIS. The physician's judgement of activity was assumed as the unique reference criterion (gold standard). Computer programmes were developed to calculate automatically the 4 activity indices; this computation appeared to correspond with manual computations in a sample of 60 appropriately selected cases. All 4 indices were closely correlated with each other (r in the range of 0.716 to 0.872), and with the physician's score (r in the range of 0.620 to 0.719). In the second phase of the study the activity index developed in part I (ECLAM) was prospectively validated, and its performance compared to that of the other scales, both as a single state index and as a transition index (i.e., its ability to assess disease activity at a single point in time and to detect variations in consecutive readings). A computer-assisted clinical chart was prepared for this purpose. This chart allowed us to calculate automatically all the indices. Two consecutive observation times (time 0, and time 1 three months later) were included in the study protocol. Data on 75 patients from 19 centres were collected, and each patient was observed twice. All the computed indices were closely correlated, both at time 0 (r ranging from 0.725 to 0.884), and at time 1 (r ranging from 0.607 to 0.833).(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum erythropoietin in cross-country skiers

Serum erythropoietin (Epo) activity, hemoglobin (Hb), and hematocrit (Ht) were determined in 21 cross-country skiers during the training season. The Epo levels were not significantly reduced in the skiers relative to the normal population (P less than 0.01 and P less than 0.001, respectively). In 11 athletes Epo, Ht, urinary gamma-glutamyltransferase, N-acetyl-beta-glucosaminidase, and microalbuminuria were determined before and after a 50-km ski race at 1600 m above sea level. A significant increase of these variables (except for Ht) was found after the competition (P less than 0.001). It is concluded that while the reductions in Hb and Ht, which are typical of several endurance exercises, are not accompanied by a renal hypoxia sufficient to stimulate Epo overproduction, the renal hypoxia reached during the strenuous exercise of the race at altitude may be effective in determining blood increases in Epo.     

Interatrial septum rupture during balloon measurement of a patent foramen ovale in a young patient presenting cryptogenic stroke.

We report the case of a 36-year-old woman admitted for cryptogenic stroke, in whom the Patent Foramen Ovale (PFO) diameter measurement, with a purpose built sizing balloon, performed before the closure procedure, was complicated with the rupture of the inter-atrial septum generating an Atrial Septal Defect (ASD) with a significant left-to-right shunt. This kind of complication may not be easy to handle, changing the initial procedural strategy from PFO to ASD closure technique requiring specific material and operator's technical skill.     

First-year results of a community-based study of stroke incidence in Umbria, Italy

The SEPIVAC study (Italian initials for "epidemiologic study of incidence of acute cerebrovascular disease") is a community-based epidemiologic survey of incidence and outcome of cerebrovascular disease in the territory of the 6th Local Health Unit, Umbria, Italy, where 49,101 people live. All cases were registered with the study either by notification from general practitioners or by check of hospital admission within the study area and in the two hospitals of Perugia. Death certificates were looked at as well. Patients were registered with the study when the clinical picture fulfilled the definition of stroke and transient ischemic attack (TIA) adopted for this study. Patients were followed up at approximately 30 days and 6 months. During the first year of the study (September 1, 1986 to August 31, 1987), 189 cases were registered: 108 suffered a "first ever in a lifetime" stroke, 30 a recurrent stroke, and 51 a "first ever in a lifetime" transient ischemic attack. Sixty-one percent of patients (71% of first strokes) had a computed tomography scan. For our study, the crude annual incidence rate of first stroke was 2.2 per 1,000 (confidence intervals 1.81-2.66); the standardized rate to the European population was 1.36 (confidence intervals 1.06-1.74). At least 83% of first strokes were due to cerebral ischemia; in 26 cases a clinical diagnosis of lacunar ischemia was made. The 30-day case fatality rate was 21%; 25% of our patients had recovered completely or almost completely after 1 month.     

emm Gene distribution among erythromycin-resistant and -susceptible Italian isolates of Streptococcus pyogenes

The phenotypes and genetic determinants for macrolide resistance were determined for 167 erythromycin-resistant Streptococcus pyogenes strains. A cMLS phenotype was shown in 18% of the erythromycin-resistant strains, while inducible resistance was apparent in 31% and the M phenotype was apparent in 50%. The emm gene type of this set of resistant isolates and that of 48 erythromycin-sensitive isolates were determined. emm2 and emm48 were recorded only in the resistant strains of the M phenotype, while approximately all of the strains harboring the emm22 gene had the cMLS phenotype. More than 80% of the emm89-positive strains had the iMLS phenotype, and the same portion of emm4 strains presented the M phenotype. emm3 is recorded only among sensitive strains. The distribution of frequencies of the genetic determinant for the virulence factor M protein was significantly different both among organisms of different types of resistance and between resistant and sensitive populations of S. pyogenes under study.     

PCR m typing: a new method for rapid typing of group a streptococci

A new approach for the M-typing of Streptococcus pyogenes is reported. Oligonucleotide primers were used in a PCR to amplify the N-terminal region of the emm gene. The presence of the PCR amplification product is associated with the corresponding M serotype. This technique offers potential advantages over other molecular typing methods.     

Reusable heterogeneous catalysts of α-amino acid racemization, 2. Factors affecting the activity of heterogeneous catalysts based on strongly basic anion exchangers in OH− form and 4-hydroxy-3-formylbenzenesulfonic acid (5-sulfosalicylaldehyde)

The kinetics of (S)-Ala racemization on heterogeneous catalysts based on eight strongly basic anion exchangers modified with 4-hydroxy-3-formylbenzenesulfonic acid (5-sulfosalicylaldehyde) (SSA) in the presence of Cu(II) ions at 25 °C was studied. The “internal capacity” value f = m_p/(V₀ — V_p) was introduced to characterize the polymers, (m_p : number of quaternary ammonium groups of the polymer sample, V₀ : total volume of the swollen polymer, V_p : volume of the inert polymeric matrix). The correlation of the observed first-order rate constants of (S)-Ala racemization with the f values of the anion exchangers was established. According to this correlation the selected anion exchangers could be divided into two types with respect to the chemical nature of the groups attached to the quaternary nitrogen atom. The chemical nature, physical structure and the degree of cross-linking of the polymeric matrix do not affect the correlation. Anion exchangers of the first type have at least one ß-hydroxyalkyl substituent at the Anion exchangers of the second type have (CH₃)₃ cationic groups. Catalysts prepared with the first type anion exchangers have greater activity as compared with catalysts based on the second type anion exchangers with the same f values. The increase in activity of heterogeneous catalysts can be partially attributed to the 10 to 68 fold increase in OH^? concentration in the internal phase of the catalysts as compared to the model homogeneous system, which contains the same amounts of the components as the heterogeneous one. Moreover, an additional acceleration is observed in the heterogeneous racemization as compared to the homogeneous one, ca. 5 fold for the second type anion exchangers and ca. 14 fold for the first type anion exchangers.     

Anomalous responses to histamine stimulation of guinea-pig oesophageal muscularis mucosae.

The incomplete tachyphylaxis of the contractile response to the H1-stimulants observed on guinea-pig oesophageal muscularis mucosae seems to be H2- and H3-antagonist as well as atropine- and tetrodotoxin-resistant. Lidocaine and eserine partially prevented this process probably by a mechanism independent of their main activity. The dualistic antagonism exerted by mepyramine and methysergide on reproducible histamine responses could be explained by a kinetic condition of "hemi-equilibrium state" together with changes of drug-receptor interaction and by non-specific properties of methysergide. On the whole, the present data indicate that the role of histamine in this tissue has still to be defined.