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L Burattini

Publications and source records attributed to L Burattini.

7 recordsLinked to original sources
PubMed1999

Time-domain analysis of beat-to-beat variability of repolarization morphology in patients with ischemic cardiomyopathy.

There is growing evidence that beat-to-beat changes in ventricular repolarization contribute to increased vulnerability to ventricular arrhythmias. Beat-to-beat repolarization variability is usually measured in the electrocardiogram (ECG) by tracking consecutive QT or RT intervals. However, these measurements strongly depend on the accurate identification of T-wave endpoints, and they do not reflect changes in repolarization morphology. In this article, we propose a new computerized time-domain method to measure beat-to-beat variability of repolarization morphology without the need to identify T-wave endpoints. The repolarization correlation index (RCI) is computed for each beat to determine the difference between the morphology of repolarization within a heart-rate dependent repolarization window compared to a template (median) repolarization morphology. The repolarization variability index (RVI) describes the mean value of repolarization correlation in a studied ECG recording. To validate our method, we analyzed repolarization variability in 128-beat segments from Holter ECG recordings of 42 ischemic cardiomyopathy (ICM) patients compared to 36 healthy subjects. The ICM patients had significantly higher values of RVI than healthy subjects (in lead X: 0.045 +/- 0.035 vs. 0.024 +/- 0.010, respectively; P < .001); 18 (43%) ICM patients had RVI values above the 97.5th percentile of healthy subjects (>0.044). No significant correlation was found between the RVI values and the magnitude of heart rate, heart rate variability, QTc interval duration, or ejection fraction in studied ICM patients. In conclusion, our time-domain method, based on computation of repolarization correlation indices for consecutive beats, provides a new approach to quantify beat-to-beat variability of repolarization morphology without the need to identify T-wave endpoints.

Electrocardiography, Ambulatory↗
PubMed1999

Beat-to-Beat repolarization variability in LQTS patients with the SCN5A sodium channel gene mutation.

Current techniques evaluating beat-to-beat variability of repolarization rely on accurate determination of T wave endpoints. This study proposes a T wave endpoint-independent method to quantify repolarization variability in a standard 12-lead ECG using a wavelet transformation. Our method was used to identify repolarization variability in long QT syndrome patients (LQTS) with the SCN5A sodium channel gene mutation. Using wavelet transformations based on the second Gaussian derivative, we evaluated repolarization variability in 11 LQTS patients with the mutation, 13 noncarrier family members, and 28 unrelated healthy subjects. Time-domain repolarization variability parameters (SDRTo, SDRTm) and wavelet parameters describing temporal (beat-to-beat) variability of repolarization in time (TVT) and in amplitude (TVA) were analyzed. Reproducibility of wavelet parameters and relationship of wavelet-based variability with heart rate and preceding RR interval were investigated. The wavelet-based method quantified beat-to-beat variability of the entire repolarization segment (regardless of QT interval identification) providing insight into variability in repolarization morphology. Our method showed that SCN5A carriers have significantly increased repolarization variability in amplitude (23% +/14% vs 8 +/- 4%, P < 0.001) and in time (14 +/- 17 ms vs 3 +/-2 ms, P < 0.004) compared to noncarriers. Variability of repolarization amplitude was found to be heart rate dependent with variability decreasing with increasing heart rate. Relative error describing reproducibility of TVA and TVT was < or = 5% and < or =10%, respectively. Our method quantifies repolarization variability in amplitude and in time without the need to identify T or U wave endpoints. Wavelet-detected repolarization variability contributes to phenotypic identification of SCN5A carriers, with more pronounced beat-to-beat variability in repolarization amplitude than in time.

Adolescent↗
PubMed1998

ECG features of microvolt T-wave alternans in coronary artery disease and long QT syndrome patients.

UNLABELLED: T-wave alternans (TWA) is a marker of myocardial electrical instability. We compared ECG features of microvolt TWA in coronary artery disease (CAD) and long QT syndrome (LQTS) patients. METHOD: The study populations consisted of 43 CAD and 39 LQTS patients. TWA was detected in resting Holter recordings using the new correlation method (CM). After preprocessing to adjust for RR variability and respiratory modulation, CM was used to quantify TWA amplitude (A(CM)), duration (N(CM)), and magnitude (MAG(CM); defined as the product of A(CM) and N(CM)). RESULTS: TWA was detected in 19 (44%) CAD and 17 (44%) LQTS patients. TWA was associated with longer RR intervals (P = 0.006) and had larger magnitudes (P = 0.067) in LQTS than CAD patients. The TWA was identified as transient (nonstationary) in 15 of 19 (79%) TWA-positive CAD patients, and in 8 of 17 (47%) TWA-positive LQTS patients (P = 0.047). CONCLUSIONS: The frequency of TWA detected with CM is similar in LQTS and CAD patients. TWA is larger in LQTS than in CAD patients, whereas TWA is more frequently transient (nonstationary) in LAD than LQTS patients. In LQTS patients, but not in CAD patients, a longer RR is associated with TWA, indicating different electrophysiologic mechanisms in the two pathologies.

Adult↗
PubMed1996

Bipolar Electrodes in the Treatment of Ectopic Pregnancy

During operative laparoscopy in the management of the ectopic pregnancy, conservative treatment consisting of linear salpingotomy and extraction of trophoblast must be carried out systematically. Until recently, tubal incision was performed with monopolar delivery systems. Bipolar electrosurgery has been used for many years, but is limited to coagulation. We applied bipolar technology in the conservative treatment of ectopic pregnancy. The instrument we used for the salpingotomy consisted of disposable Bilap needle or hook electrodes with shaft diameter of 5 mm and working length 33 cm. The trophoblast was extracted with a hydrodissection pump provided with 10- or 5-mm probes without irrigation holes. The electrodes were connected to an electrosurgical generator with maximum cutting power of 70 W. This system offers cutting in bipolar applications that are designed to eliminate current passing through tissues other than those selected. The conductive electrodes are closely spaced, reducing the energy requirements and power delivered to the surrounding tissue. The operative procedure was performed in 12 women. We had no persistent trophoblastic proliferation, and no patient required additional treatment.

Journal Article↗
PubMedDate not supplied

ACTH 1-17 effects in oncology.

Since November 1981, 90 cancer patients treated with cytotoxic chemotherapy (CMF, FAC, FAM) have been studied to evaluate whether the administration of Synchrodyn 1-17, 100 micrograms i.m. a day for 15 consecutive days, could reduce some side effects caused by the cytotoxic drugs. Nausea, vomiting and weakness which are the most frequent side effects generally found to be very upsetting to patients, were less pronounced in the treated patients than in patients treated with a placebo. The performance status was not modified by the treatment. Skin pigmentation was noted in the majority of cases and it appeared to be related to the sustained treatment with high dosages of the peptide. Some side effects were observed in the treated patients such as sodium retention and hypertension, hyperglycemia. Successively we have begun to study the circadian rhythm of the cortisol, which often changes during the advanced stages of the illness and which chemotherapy does not seem to alter.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Stroke unit: a cardio-cerebral approach.

Stroke units are special units where stroke patients receive, simultaneously, medical and physical treatment. Compared to general neurological and medical wards, stroke units show a significant reduction of short- and long-time mortality, and an improvement of long-term quality of life. Nevertheless, mortality in these units is still high (1-year mortality approximately 32%; 5-year mortality degrees 60%), and consequently, new approaches are needed to control stroke parameters during the acute phase, with the goal to reduce mortality rates. The philosophy of our stroke unit in Fermo (Italy), is to establish a strong association between heart and brain care by approaching each stroke patient as a cardiocerebral patient. In particular, we perform 12-lead Holter ECG monitoring, to prevent the vicious cycle affecting correct cerebral and cardiac functions, and to react to cardiac complications, mostly arrhythmias, that can worsen cerebral damage. Holter ECG monitoring allows a fast physiotherapeutic approach, a better evaluation of metabolic parameters, and collectively, a better global evaluation of the patient during the acute phase of disease. In two years of activity, 80 patients that were admitted to our stroke unit during 1998, and treated as cardio-cerebral patients, were followed-up. This combined treatment decreased the 1-year mortality rate by about 30%, in comparison with the 22% mortality rate reported in the literature. These results confirm the validity of stroke units, as well as of our approach based on cardio-cerebral control of each stroke patient.

Adult↗