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C Mastrangelo

Publications and source records attributed to C Mastrangelo.

11 recordsLinked to original sources
PubMed2001

The effects of atrial electrical remodeling on atrial defibrillation thresholds.

Electrical remodeling of atrial fibrillation may account for the increase in atrial defibrillation thresholds over time. The aim of this study was to examine the time course of electrical remodeling and the benefit of early defibrillation on the defibrillation threshold. Twenty-six mongrel dogs weighing 27.6 +/- 3.3 kg were induced into AF by repeated high output burst atrial pacing. Eight dogs were paced for multiple time periods of 5, 20, 40, and 60 minutes. Five dogs each had burst pacingfor 4 hours and 8 hours, and eight dogs were paced at a high rate (640 beats/min) for 48 hours. Biphasic atrial defibrillation shocks with a pulse width of 3/3 ms synchronized to the left apical electrogram were delivered to coil electrode catheters positioned in the lateral left and right atria. Defibrillation voltage was increased from 50 V in 20- to 30-V steps until defibrillation was successful. As the pacing period increased, a decrease in atrial fibrillation cycle lengths and atrial effective refractory period was not observed before 8 hours. Similarly, the defibrillation threshold did not change significantly until the 8-hour pacing period was reached. The defibrillation thresholds were 69 +/- 28 V for 5 minutes, 64 +/- 20 V for 20 minutes, 99 +/- 85 V for 40 minutes, 78 +/- 51 V for 60 minutes, 78 +/- 38 V for 4 hours, 124 +/- 33 V for 8 hours, and 133 +/- 32 V for 48 hours (mean +/- SD) (P < 0.05). Atrial electrical remodeling in a rapid atrial pacing canine model is not observed until after 4 hours of burst atrial pacing. The atrial defibrillation threshold increases with increasing duration of burst atrial pacing, and follows a similar time course to other parameters of electrical remodeling.

Animals↗
PubMed1998

Short stature and body proportion in thalassaemia.

Short stature and short trunk have been reported in thalassaemic patients. We report a study on stature and body proportions in 476 patients (2-36 years old) with beta-thalassaemia major, followed in 12 Italian centres. Auxological data (standing height, sitting height, subischial leg length, target height), haematological data (age at first transfusion, age at start of desferrioxamine [DFX] chelation, mean dose of DFX, ferritin values) and information regarding the presence of endocrine disorders and of bone lesions, were collected and analysed according to the age of the patients, in order to investigate the natural history of the disproportion and the role of siderosis, DFX toxicity and endocrine disorders. Our data indicate that about 18% of thalassaemic patients exhibit short stature; disproportion between the upper and lower body segments is present in 14%; however, a short trunk despite normal stature is present in another 40% of patients. This is due to a spinal growth impairment which starts in infancy and progressively aggravates. We think that a short trunk is peculiar to the disease itself; however, other factors such as hypogonadism, siderosis, or DFX-induced bone dysplasia are probably involved in aggravating the body disproportion in these patients.

Adolescent↗
PubMed1992

Randomized comparison of ceftriaxone versus ceftriaxone plus amikacin for the empirical treatment of infections in patients with altered host defense: microbiological and clinical evaluation.

Two hundred and eighty-four febrile episodes in immunocompromised patients were treated with ceftriaxone alone or in combination with amikacin. In the ceftriaxone-treated group, 60 out of 143 febrile episodes were microbiologically documented, while in the group receiving the combination therapy, there were 32 out of 140 (p = 0.0007). Gram-positive microorganisms were more common than gram-negative ones, accounting for 59 of the 101 isolated bacteria. The ceftriaxone regimen appeared to have a response rate comparable to the combination regimen (73.91 vs. 78.88%). Superinfections occurred under both regimens.

Adult↗
PubMedDate not supplied

[Cephalometric evaluation of hyoid bone position in patients with obstructive sleep apnea].

AIM: The aim of this study was to evaluate cephalometrically the relationship between hyoid bone position and obstructive sleep apnea (OSA). METHODS: Two groups were examined: the experimental Group (SG), composed of 15 OSA patients, and the Control Group (CG), composed of 15 healthy subjects. Both SG and CG patients were subjected to lateral teleradiography. On each radiography were effected cephalometric measurements to evaluate hyoid bone position and the results obtained were compared. RESULTS: From data comparison it turned out that, as already described in the literature, in OSA patients hyoid bone is, on average, in a lower and in a more posterior position than in control group patients. CONCLUSION: This altered hyoid bone position may influence tongue position and upper airway patency. All this makes it clear that cephalometric study is important for diagnosis and treatment of OSA patients.

Adult↗