Altered values of heart rate variability in patients with relapse of atrial fibrillation during the first week after electrical cardioversion: preliminary data.

BACKGROUND: It has not so far been elucidated whether the autonomic nervous system plays a role in the pathogenesis of atrial fibrillation relapse after electrical cardioversion. METHODS: In 40 consecutive patients with atrial fibrillation (22 males, 18 females, mean age 60 +/- 2 years) submitted to successful electrical cardioversion (external in 26 and low-energy internal in 14) we evaluated the heart rate variability (24-hour Holter recording) immediately after restoration of sinus rhythm in order to assess the cardiac sympatho-vagal drive. RESULTS: Patients with atrial fibrillation relapse within the first week of electrical cardioversion were characterized by a significantly higher low/high frequency ratio. CONCLUSIONS: Despite the heterogeneity of the studied population (concerning both the therapy and etiology of atrial fibrillation), our data strongly suggest that the evaluation of the low/high frequency ratio by means of power spectral analysis immediately after electrical cardioversion is a useful tool for the identification of those patients who are prone to atrial fibrillation recurrence. Our conclusions are supported by the finding of high positive and negative predictive values for the low/high frequency ratio both in the 24-hour period and during daytime.

Left origin of the atrial esophageal signal as recorded in the pacing site.

Clear atrial depolarizations from inside the esophagus have always been recorded in electrocardiology, but their precise origin is still under discussion. Though atrial signals are recorded along most of the esophagus, pacing of the atria is possible only in a short tract, probably where the esophagus is in contact with the posterior left atrium wall. In order to ascertain which portion of atria gives rise to the esophageal atrial signal recorded in the atrial pacing segment, we examined 37 patients with normal P waves on the standard ECG by inserting esophageal and endocavitary catheters. The interval between the earliest start of the P wave and the bipolar atrial deflection, was measured both through the esophagus (PA-Eso) and the Hisian region (PA-His) (the latest depolarization of interatrial septum). The former was longer than the latter (P < 0.001) in 36 of 37 patients, showing that the esophagus recorded atrial signal, at the site of effective pacing, originates outside the interatrial septum. As the atrial depolarization recorded through the esophagus is significantly delayed compared with the Hisian region recording, a pure left origin of the esophageal signal can be hypothesized. This is supported by the well-known delayed depolarization, during sinus rhythm, of the left atrium posterior wall compared with the right atrium and interatrial septum. Measuring the interval between the standard ECG P wave and atrial depolarization recorded through esophagus in the site of effective pacing, provides a reliable noninvasive estimate of interatrial time conduction.

[The study of biohumoral parameters during surgical limb lengthening]. / Studio di alcuni parametri bio-umorali in corso di allungamento chirurgico degli arti.

The authors report a series of 7 patients undergoing surgical limb extension with a total of 9 segmentary extensions. The study focuses on the trend of 4 biohumoral parameters (ESR, PCR, leukocytes, neutrophil percentage) during the various stages of surgery. The authors conclude that, in conjunction with clinical assessment, these parameters represent a valid tool for monitoring infections during the course of extension. Of these parameters, PCR was found to be the most sensitive marker. If evaluated using the general trend of these markers, surgical limb lengthening is not dissimilar to the fracture healing process.

[The predictive value for major arrhythmic events of ventricular arrhythmias, particularly nonsustained ventricular tachycardias, in the subacute phase of a fibrinolyzed infarct. An analysis of GISSI-2 data. Gruppo Italiano per lo Studio della Streptochinasi nell'Infarto Miocardico]. / Significato predittivo per eventi aritmici maggiori delle aritmie ventricolari, in particolare delle tachicardie ventricolari non sostenute, nella fase subacuta di un infarto fibrinolisato. Analisi dei dati del GISSI-2.

BACKGROUND: The relationship between ventricular arrhythmias (VA) in the subacute phase of a myocardial infarction (MI) and subsequent major arrhythmic events, i.e. sustained ventricular tachycardia (SVT) and sudden death (SD), is well known. The importance of left ventricular dysfunction in the same context is also well established. The vast majority of the data in the literature come from the prefibrinolytic era and/or are derived from limited data bases. MATERIALS, METHODS AND RESULTS: We examined the large, uniform GISSI-2 population of acute fibrinolysed myocardial infarctions in order to evaluate the significance and predictive power of VA detected by Holter monitoring during the subacute phase. Particular attention was paid to the occurrence of nonsustained ventricular tachycardias (NSVT) since their role is still uncertain, so it is hard to assess the utility of invasive measures such as programmed electrical stimulation (PES). Left ventricular function was evaluated by mono-, and two-dimensional echocardiography. Holter monitoring was available in 8,676 patients; a six-month follow-up, as regards mortality was completed in 8,552 patients (98.5%) and, as regards SVT incidence, in 7.713 (88.9%). During the follow-up 256 patients died (3%), 84 out of them suddenly (1%). Twenty-six [corrected] patients out of 7,713 (0.3%) experienced one or more SVT. The relationship between VA, left ventricular dysfunction and major arrhythmic events was evaluated by odds ratios (OR) and their confidence intervals (CI). Odds ratios for the combined end-point (SD and/or SVT) was 4.49 (CI 95% 2.69-7.51) if the Holter showed > 10 VEB/hour; 2.34 (CI 1.48-3.68) if couplets were present; 3.26 (1.52-6.99) if NSVT were present; 3.02 (2.02-4.50) if any complex ventricular arrhythmia was detected. Left ventricular disfunction seemed to exert a more powerful influence: OR 9.80 (CI 5.75-16.69) for SD and/or SVT. Any arrhythmic parameter had very low positive (< or = 3%) and very high (approximately 99%) negative predictive power. Multivariate analysis (Cox Model) including major prognostic factors confirmed the independent prognostic value of frequent VA (RR 2.75; 95% CI 1.58-4.79), couplets (RR 1.91; CI 1.28-2.86); complex VA (RR 2.02; CI 1.36-3.00). NSVT, after adjusting for the selected risk factors, was not independently associated with a worse prognosis. CONCLUSIONS: Ventricular arrhythmias detected by Holter monitoring during the subacute phase of a MI still have prognostic significance for major arrhythmic events in the fibrinolytic era. The presence of NSVT triples the risk of SD and/or SVT in the six months after an acute MI, but loses any predictive power in a multivariate analysis. Only 6.6% of the patients showed one or more episodes of NSVT in the Holter recording. If the ongoing clinical trials, MUSTT and MADIT, will confirm the usefulness of PES in such patients, the benefit will be confirmed to a very small proportion of the patients at risk of specific diagnostic tests. The positive predictive power of VA is very low and it is therefore mandatory to add other non-invasive variables to the screening to identify the subgroups at greatest risk. On the other hand the very high (99%) negative predictive power of VA and left ventricular dysfunction enables us to identify a large population of infarcts with a negligible risk, who need no further sophisticated investigations. From the point of view of the cost/benefit evaluation this seems to be an outstanding result.

[Indications for the use of external fixator in orthopedics and traumatology during the developmental age]. / Le indicazioni al fissatore esterno in ortopedia e traumatologia dell'età evolutiva.

The paper illustrates the characteristics of external fixators (EF) (Wagner, FEA, Ilizarov) regularly used in pediatric surgery. Attention is focused on the indications for their use in orthopedics and traumatology during the developmental age. In conclusion, their use, even though in traumatology this is more restricted than in adults, reduces many complications which may arise from traditional treatment. In addition, it is well tolerated and allows pathologies to be treated which were difficult to cure in the past.

[Cross-reactivity of milk proteins: statistical analysis of RAST results]. / Reattività crociata fra le proteine del latte con l'analisi statistica dei risultati del RAST.

RIA dosages of specific IgE antibodies to cow milk, alpha-lactalbumin, beta-lactoglobulin, casein, cheddar and mould cheese were determined in 440 patients. Statistic analysis has been carried out with: 1) the linear regression and correlation coefficient r2: 2) U test of Mann-Whitney and then S test of Kendall Results show that casein has low allergenicity in comparison to other cow's milk proteins. It could be unnecessary to quantify specific IgE to cow milk and cheeses. From the observed data we could suppose that the formulas with casein/blood protein ratio similar to maternal milk may be more allergenic than casein based ones.

Dermatophagoides and storage mites: statistical analysis of RAST results.

R.I.A. dosages of specific IgE antibodies to Dermatophagoides pteronyssinus, Dermatophagoides farinae (house dust mites), Acarus siro, Lepidoglyphus destructor, and Tyrophagus putrescentiae (storage mites) in 467 unselected patients were statistically analyzed. A significant noncorrelation between specific IgE antibodies to storage mites and those to house dust mites has been found, suggesting that storage mites have their own allergenic specificity.

The modified Wagner method for surgical lengthening of the limbs.

The method proposed by Wagner in 1971 for surgical lengthening of the limbs was widely used by the authors for the treatment of dysmetria and (since 1976, for the first time in Italy) for disharmonic hypometria. The limitations of this method were revealed, however, by increasing knowledge in this field and the advent of new biological concepts of bone regeneration. The authors report 51 lengthenings carried out between 1982 and 1987 according to their own modification of the Wagner method. They conclude that the Wagner external fixator associated with corticotomy achieves excellent results, decreasing the number of surgical stages as well as the risk of infection and delay in consolidation.

[Proposal for a quality control procedure for rotating gamma camera tomographic systems]. / Proposta di procedura di controllo di qualità per sistemi tomografici a gamma camera rotante.

Single photon emission computerized tomography using a rotating gamma camera needs accurate calibration of electromechanical components, detection system and reconstruction software. A complete group of quality control procedures, developed on the basis of experience and experimental data acquired using a series of widely used gamma camera SPECT systems is presented. The procedures are divided into controls related to the rotational movement. of the detector and controls on the principal physical parameters characterizing a tomographic image. All quality controls here presented were performed with commercial phantoms.