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Biomedical subjects

F Lombardi

Publications and source records attributed to F Lombardi.

At least 55 records · Page 3Linked to original sources
PubMed1998

Quantifying electrocardiogram RT-RR variability interactions.

A dynamic linear parametric model is designed to quantify the dependence of ventricular repolarisation duration variability on heart period changes and other immeasurable factors. The model analyses the beat-to-beat series of the RR duration and of the interval between R- and T-wave apexes (RT period). Directly from these two signals, a parametric identification procedure and spectral decomposition techniques allow RT variability to be divided into RR-related and RR-unrelated parts and allow the RT-RR transfer function to be calculated. RT variability is driven by RR changes at low frequency (LF, around 0.1 Hz) and high frequency (HF, at the respiratory rate), whereas, at very low frequencies, the RR-unrelated contribution to the total RT variability is remarkable. During tilt at LF the RR-related RT percentage power increases (p < 0.02), the RR-unrelated RT percentage power remains unchanged, the gain of the RT-RR relationship largely increases (p < 0.001), and the phase is not significantly modified. Both the RR-related and the RR-unrelated RT percentage powers at LF are not affected by controlled respiration, and an increase in the RT-RR gain at HF is observed (p < 0.02). The proposed analysis may help to describe the regulation of the ventricular repolarisation process and to extract indexes quantifying the coupling between heart period and ventricular repolarisation interval changes.

Electrocardiography↗
PubMed1998

Performance assessment of standard algorithms for dynamic R-T interval measurement: comparison between R-Tapex and R-T(end) approach.

Three automatic approaches to ventricular repolarisation duration measurement (R-Tapex, R-T(end threshold) and R-T(end fitting) methods) are compared on computer-generated and real ECG signals, in relation to their reliability in the presence of the most common electrocardiographic artefacts (i.e. additive broadband noise and additive and multiplicative periodical disturbances). Simulations permit the evaluation of the amount of R-T beat-to-beat variability induced by the artefacts. The R-T(end threshold) method performs better than the R-T(end fitting) one, and, hence, the latter should be used with caution when R-T(end) variability is addressed. Whereas the R-Tapex method is more robust with regard to broadband noise than the R-T(end threshold) one, the reverse situation is observed in the presence of periodical amplitude modulations. A high level of broadband noise dose not prevent the detection of the central frequency of underlying R-T periodical changes. Comparison between the power spectra of the beat-to-beat R-T variability series obtained from three orthogonal ECG leads (X,Y,Z) is used to assess the amount of real and artefactual variability in 13 normal subjects at rest. The R-Tapex series displays rhythms at high frequency (HF) with a percentage power on the Z lead (57.1 +/- 4.9) greater than that on the X and Y leads (41.9 +/- 4.6 and 46.1 +/- 4.9, respectively), probably because of respiratory-related artefacts affecting the Z lead more remarkably. More uniform HF power distributions over X,Y,Z leads are observed in the R-T(end threshold) series (31.8 +/- 3.8, 39.2 +/- 4.1 and 35.1 +/- 4.2, respectively), thus suggesting minor sensitivity of the R-T(end threshold) measure to respiratory-related artefacts.

Algorithms↗
PubMed1998

Traumatic brain injury in childhood: intellectual, behavioural and social outcome into adulthood.

In order to obtain indicative data regarding intellectual, behavioural and social outcome into adulthood of subjects with a history of childhood head injury (CHI), twenty adults were selected who had been referred to the Neuropsychology Unit at the University of Parma at the time of a traumatic brain injury (TBI) at an age between 8 and 14 years. The level of intellectual and behavioural impairment was determined and rated by WISC and WAIS IQa and by the frequency of maladjustive behaviour. GOS score and Barthel index were used to detect the level of disability. Social adjustment and community integration were determined by the Social Adjustment Scale (SAS) and the Community Integration Questionnaire (CIQ) respectively. Results indicate that (1) subjects who suffer a severe CHI present a higher pre-injury incidence of character disturbances than the normal population and injury-related difficulties to socialize which persist long-term and add to other problems; (2) even though intellectual and functional sequelae are frequent in these children in adulthood and do not improve in their correlation to age, these do not appear to be the prevailing problems and (3) the prevailing problems seem to be social maladjustment and poor quality of life, which are still present several years post-injury and seem to be related to behavioural and psychosocial disorders in spite of an increased ADL-functioning. This has already been clearly demonstrated in the case of adulthood trauma.

Activities of Daily Living↗
PubMed1998

Assessment of the coupling between RTapex and RR interval as an index of temporal dispersion of ventricular repolarization.

To evaluate the dynamic characteristics of the relationship between the RT and RR intervals we analyzed the RR/RTapex variability interaction with a dynamic parametric model whose parameters can be directly estimated from the beat-to-beat series RR and RTapex intervals. The model is designed to separate the fraction of RTapex variability driven by RR changes from that independent of RR variations and to quantify the gain and phase of the relationship between RR and RTapex intervals. The percentage of RTapex variability driven by RR variability was significantly greater in young normal subjects in comparison with postmyocardial infarction patients as well as with age-matched control subjects. This new approach based on the quantification of the RTapex variability dependent and independent of beat-to-beat RR interval changes could be used to quantify the degree of uncoupling between the two signals thus providing a new and noninvasive index of temporal dispersion of ventricular repolarization.

Adult↗
PubMed1998

Carcinoid heart disease from ovarian primary presenting with acute pericarditis and biventricular failure.

A case is described of a 54 year old woman who had acute pericarditis with large exudative effusion accompanied by severe right and left ventricular failure. The patient was finally diagnosed with carcinoid heart disease from an ovarian carcinoid teratoma. She was treated with octreotide--a somatostatin analogue--followed by radical surgical resection of the neoplasm. At one year follow up only mild carcinoid tricuspid regurgitation remained. Only 16 cases of carcinoid heart disease from an ovarian primary have been described in literature. Moreover clinically manifest acute, nonmetastatic pericarditis and left heart failure are not considered as possible presentations of carcinoid heart disease, whatever the origin. In a recent series a small pericardial effusion was considered an infrequent and unexpected echocardiographic finding in carcinoid heart patients. One case of "carcinoid pericarditis" has previously been described as a consequence of pericardial metastasis. Left sided heart involvement is usually caused by bronchial carcinoids or patency of foramen ovale; both were excluded in the case presented.

Carcinoid Heart Disease↗
PubMed1997

High-dose chemotherapy and autologous bone marrow transplantation compared with MACOP-B in aggressive B-cell lymphoma.

BACKGROUND: We compared a regimen of six chemotherapeutic agents administered sequentially at high doses, followed by myeloablative treatment and bone marrow transplantation, with a regimen of methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B) as initial or salvage treatment for adults with diffuse large-cell lymphoma. METHODS: Ninety-eight eligible patients with diffuse large-cell lymphoma of the B-cell type were randomly assigned to receive either MACOP-B (50 patients) or high-dose sequential therapy (48 patients). The study design allowed for patients in whom the assigned treatment failed to cross over to the other treatment group. RESULTS: After a median follow-up of 55 months, the patients given high-dose sequential therapy, as compared with those treated with MACOP-B, had significantly higher rates of complete response (96 percent vs. 70 percent, P=0.001), freedom from disease progression (84 percent vs. 49 percent, P<0.001), freedom from relapse (88 percent vs. 70 percent, P=0.055), and event-free survival (76 percent vs. 49 percent, P=0.004). The difference in overall survival at seven years, which also favored the group assigned to high-dose sequential therapy, was marginally significant (81 percent vs. 55 percent, P=0.09). CONCLUSIONS: High-dose sequential therapy is superior to standard-dose MACOP-B for patients with diffuse large-cell lymphoma of the B-cell type.

Adolescent↗
PubMed1997

Analyses of prognostic factors in a retrospective review of 92 children with ependymoma: Italian Pediatric Neuro-oncology Group.

The principal aim of this report is to present the results of multivariate analyses conducted to identify clinical prognostic factors in 92 children aged < 16 years with ependymoma (EPD) retrospectively collected in seven Italian centres. They were treated over a 16-year period (1977-1993). Treatment modalities varied. Surgery and radiotherapy (RT) was the "gold standard" management method for the majority of these children. Only in the late 1980s did some of them receive chemotherapy (CT), mainly with vincristine, lomustine (CCNU) and prednisone. The median follow-up of the entire study population is 36 months (average 43 months; range 12 to 214 months). The 10-year overall (OS) and the progression-free survival (PFS) of the study population were 55.5% (CI 41.4-69.4%) and 34.7% (CI 21.4-47.8%), respectively. Age (< 5 years; > 5 years), sex, site (infratentorial vs. supratentorial), histology (anaplastic/malignant vs. non-anaplastic/non-malignant), type of resection (complete vs. incomplete); use and fields of RT, and of CT employed were entered in a multivariate regression model to test their impact on OS and PFS. On univariate analysis, radical surgery, the use of RT and age more than 5 years at the time of diagnosis achieved statistically significant values for predicting long-term OS and PFS. Histology reached marginal statistical significance but only for PFS. When those variables were entered in a multivariate analysis only radical resection (P = 0.00142 and 0.0001) resulted a significant factor for predicting long-term OS and PFS, while the use of RT reached a marginal statistical significance, but only for PFS (P = 0.05). Children who had the tumour completely resected did significantly better than all the others who had less than a complete resection, with a 10-year OS and PFS for the two groups of patients of 69.8% (CI 53-86.5%) and 57.2% (CI 40.3-75%) and of 32.5% (CI 8.5-57.6%) and 11.1% (0-24.4%), respectively. These findings suggest that, for childhood EPD, radical resection should be pursued as much as reasonably possible. Thus, it seems justified proposing for future trials, patient stratification by entity of surgical resection.

Adolescent↗
PubMed1997

Treatment of childhood post-irradiation sarcoma of bone in cancer survivors.

PATIENTS AND METHODS: This is a retrospective review of five children with post-irradiation bone sarcoma (PIS). Age at PIS onset ranged between 10 and 17 years (median 11). They were treated with a chemotherapy regimen, similar to that in use for primary osteogenic sarcoma, consisting of vincristine and high-dose methotrexate alternated with cisplatinum and ifosfamide, given for 12 months. RESULTS: In all children chemotherapy induced a complete clinical remission. Four of them were alive in continuous complete remission at 1, 2, 4, and 12 years from the diagnosis of bone sarcoma. One girl recurred 3 years from PIS diagnosis and was salvaged by repeating the same chemotherapy program: she remained alive in second complete remission 8 years from relapse. CONCLUSIONS: In spite of an intensive treatment previously given for the primary tumor, this drug schedule proved to be feasible and short-term side effects were manageable. Chemotherapy alone, using an intensive regimen effective for primary osteogenic sarcoma, may be an adequate therapy for childhood post-irradiation sarcoma.

Adolescent↗
PubMed1997

Distal intramural spread in adenocarcinoma of the lower third of the rectum treated with total rectal resection and coloanal anastomosis.

PURPOSE: This study was designed to evaluate the frequency of microscopic distal intramural spread in rectal adenocarcinoma and its correlation to other histopathologic prognostic factors. METHODS: We examined 55 patients with adenocarcinomas of the lower one-third of the rectum and measured the extent of distal intramural spread in the submucosa and/or muscular layer in comparison with Dukes Stage, diameter of tumor, distance of distal margin of resection from tumor, depth of infiltration into perirectal adipose tissue, nodal status, neoplastic infiltration of lymphatic vessels, blood vessels, and nervous branches. RESULTS: Distal intramural spread was found in 40 percent of patients, 77 percent of whom had advanced tumors with nodal metastases. Distal intramural spread appeared to be strictly related to tumor size (superior to 40 mm), infiltration of the perirectal adipose tissue, multiple positive lymph nodes, presence of neoplastic emboli in the intramural lymphatic vessels, and neoplastic invasion of the nervous branches. Local recurrence occurred in one Dukes Stage B patient with a positive distal margin of resection and in four patients with a negative distal margin of resection: three Dukes Stage C and one Dukes Stage B patients with neoplastic involvement of the circumferential margin of resection of the mesorectum. CONCLUSION: These preliminary data suggest that distal intramural spread may carry little importance in determining local recurrence of rectal adenocarcinoma.

Adenocarcinoma↗
PubMed1997

Pilot study of primary chemotherapy with doxorubicin plus paclitaxel in women with locally advanced or operable breast cancer.

A pilot study of primary chemotherapy with bolus doxorubicin plus paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) infused over 3 hours was performed in 38 women with locally advanced and 41 with stage II/III breast cancer. Patients received four cycles of primary chemotherapy followed by surgery and treatment with cyclophosphamide/methotrexate/5-fluorouracil for six cycles. Preliminary data are available on 73 patients. Doxorubicin plus paclitaxel was well tolerated. Primary toxicity consisted of grade 1 or 2 reversible peripheral neuropathy and grade 3 alopecia. After a median follow-up of 13 months, none of the patients have developed cardiac toxicity or any significant alteration of the left ventricular ejection fraction, which was measured before treatment, at each cycle of doxorubicin plus paclitaxel, and every 3 months thereafter. Major clinical response of the breast tumor was observed in 88% of patients. At pathologic examination of the surgical specimen, 40% were pT1, 15% had no macroscopic tumor residue, and 7% had complete disappearance of invasive neoplastic cells. After a median follow-up of 17 months for patients with locally advanced breast cancer, freedom from progression was 67%, disease-free survival was 71%, and overall survival was 74%. The same end points were 100% for patients with stage II/III disease, with a shorter median follow-up of 10 months. In conclusion, doxorubicin plus paclitaxel is safe, feasible, and effective, and can be used as primary or adjuvant chemotherapy to assess its actual therapeutic role in women with early breast cancer.

Adult↗
PubMed1996

Linear and nonlinear dynamics of heart rate variability after acute myocardial infarction with normal and reduced left ventricular ejection fraction.

We analyzed heart rate variability (HRV) in 2 groups of patients after acute myocardial infarction with normal and reduced ejection fraction (EF) by considering both the power of the 2 major harmonic components at low and high frequency and 2 indexes of nonlinear dynamics, namely the 1/f slope and the correlation dimension D2. HRV of patients with a reduced EF was characterized by a diminished RR variance as well as a different distribution of the residual power in all frequency ranges, with lower values of the low-frequency component expressed in both absolute and normalized units, and of the low- to high-frequency ratio. In these patients we also observed a steeper slope of the negative regression line between power and frequency in the very low frequency range. The presence of a smaller fractal dimension was suggested by a lower D2. Thus, in patients after acute myocardial infarction with a reduced EF, the reduction in HRV is associated with a different distribution of the residual power in the entire frequency range, which suggests a diminished responsiveness of sinus node to neural modulatory inputs.

Case-Control Studies↗