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M Maestri

Publications and source records attributed to M Maestri.

33 records · Page 2Linked to original sources
PubMed1995

The effect of beta-blockade therapy on the response to exercise training in postmyocardial infarction patients.

Cardiac rehabilitation after a myocardial infarction has been shown to improve exercise capacity. Beta blockade has been shown to be effective in treating angina and reducing mortality, but studies are controversial as to whether beta-blockade therapy attenuates the effects of training. We attempted to study the effects of beta blockade (metoprolol) on the response to training in patients enrolled in a cardiac rehabilitation program after an uncomplicated myocardial infarction. We studied 27 patients with a recent uncomplicated myocardial infarction who were subdivided in two groups: Group 1 (13 patients) not taking a beta blocker, and Group 2 (14 patients) taking metoprolol (mean 142 +/- 57 mg daily). All patients underwent a maximal cardiopulmonary exercise test before and after a 3-month training program. The training intensity was designed to approximate the ventilatory threshold. Results showed an increase in peak VO2 in both Group 1 (27%, p < 0.01) and Group 2 (33%, p < 0.001), and an increase in VO2 at the ventilatory threshold (39% in Group 1 and 28% in Group 2, p < 0.01). The mean changes in exercise capacity were not different between groups. It was concluded that metoprolol did not influence the beneficial effects of a cardiac rehabilitation program in postmyocardial infarction patients.

Adrenergic beta-Antagonists↗
PubMed1993

[Hemodynamic changes in liver and multi-organ transplantation].

Multivisceral transplantation is a surgical technique developed as treatment for abdominal metastatic and/or multifocal malignancies. At present its clinical employment is reduced by our fragmentary knowledge of the intraoperative and postoperative outcome. The aim of this study is to compare intraoperative hemodynamic and respiratory changes during multivisceral transplantation (MTV, n = 12) and liver transplantation (OLTX, n = 14). The observations have been carried out a 4 phases: basal (I), visceral (II), reperfusion (III), final (IV). Phase I does not show differences between MTV and OLTX. In phase II MTV presents a lower temperature (T) and pulmonary arterial pressure (PAP) (p > 0.05). Phase III is marked by increasing T differences (p < 0.05), lower cardiac frequency (CF), pH and base excess (BE) (p < 0.05). PAP and cardiac output (CO) show a higher value in MTV (p < 0.05). Phase IV reports the vital signs close to normality in both groups, except pH in MTV (p > 0.05).

Animals↗
PubMed1990

The characterization of plasma-modified polydimethylsiloxane interfaces with media of different surface energy.

The effect of interfacing fresh pig blood with polydimethylsiloxane (PDMS) samples of different surface energies and chemistries is presented. PDMS-treated surfaces were obtained using oxygen plasmas. Aging in air produced rather hydrophobic surfaces, although less hydrophobic than the untreated one, due to hydrophobic recovery. Aging in water hindered it, therefore the surface remained hydrophilic. The concentration of albumin and fibrinogen was measured as a function of contact time with fresh pig blood with untreated, treated and aged in air, and treated and aged in water surfaces. The albumin concentration changed in a constant fashion. Fibrinogen depletion was observed for both treated surfaces. In the case of most hydrophobic surface a 'passivating layer' was formed. The same effect was not possible for the hydrophilic surface, due to the low albumin/fibrinogen-treated surface fracture energy.

Animals↗
PubMed1989

Assessment of left ventricular filling in patients with systemic hypertension. A Doppler echocardiographic study.

To assess left ventricular (LV) diastolic function in patients with hypertension, a Doppler echocardiographic study of transmitral blood flow (TBF) was performed in 46 hypertensive patients (H), 18 without (H1) and 28 with (H2) left ventricular hypertrophy and in 25 age-matched normal subjects (N). All patients showed normal systolic function. The following indices of Doppler TBF were measured: peak flow velocity during early filling (Evel), atrial systole (Avel) and their ratio (E/Avel); area under early filling phase (Earea), area under atrial systole (Aarea), expressed as a percentage of total diastolic area and their ratio (E/Aarea); deceleration half-time (DHT) of early filling phase. When compared with N, H1 and H2 showed significant reductions in early filling indices and an increase in atrial contribution parameters. (Evel = 0.62 +/- 0.1(N), 0.52 +/- 0.1(H1) P less than 0.01, 0.44 +/- 0.1(H2) P less than 0.001; Earea = 56 +/- 5(N), 48 +/- 5(H1) P less than 0.001, 43 +/- 6(H2) P less than 0.001; Avel = 0.49 +/- 0.1(N), 0.59 +/- 0.1(H1) P less than 0.01, 0.69 +/- 0.14(H2) P less than 0.001; Aarea = 26 +/- 5(N), 41 +/- 4(H1) P less than 0.001, 47 +/- 7(H2) P less than 0.001). Also DHT was significantly prolonged, compared with N (80 +/- 12 msec), in H1 (90 +/- 12 msec, P less than 0.01) and H2 (105 +/- 20 msec, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Nonbiodegradable expanded polytetrafluoroethylene-covered stent implantation in porcine peripheral arteries: histologic evaluation of vascular wall response compared with uncoated stents.

PURPOSE: To test the vascular wall response to an expanded polytetrafluoroethylene-covered stent, compared with conventional stenting, up to 6 months after deployment in the vascular district of a swine model. METHODS: Fourteen minipigs underwent implantation of expanded polytetrafluoroethylene-covered stents (CS) and bare stents (BS) in five peripheral arteries. Animals were killed at different time points (from 1 to 180 days). Histopathologic assessment by morphologic and morphometric analysis and by scanning electron microscopy (SEM) were used to assess the incorporation characteristics and re-endothelialization extent of the two types of stents. RESULTS: A total of 70 stents (14 CS and 14 BS in the renal arteries; 28 CS in the iliac arteries, and 14 CS in the aorta) were implanted. Microscopic examination confirmed the absence of occlusive thrombi in both the CS and BS groups. Microthrombi were observed in 10 of 13 CS (77% of cases) and in four of four BS (100% of cases, p < 0.05). Inflammation was mild in 69% of segments in which a CS was implanted and in 74% of segments in which a BS was implanted (p = NS), while a severe inflammatory reaction was observed in 6% of CS segments and in 8% of BS segments (p = NS). No differences were detected at the long-term analysis between neointimal thickness in CS compared with BS segments (0.46 +/- 0.18 mm vs 0.42 +/- 0.26 mm at 90 days and 0.36 +/- 0.08 mm vs 0.35 +/- 0.04 mm at 180 days; p = NS, respectively). At SEM analysis, re-endothelization was evident 15 days after the implant in both CS and BS starting from the stent edges. CONCLUSION: CS implantation did not elicit a more severe thrombotic deposition compared with that of BS. A similar inflammatory reaction of the arterial wall was present in the two stent groups 3 and 6 months following the implant. In addition, CS implantation did not stimulate excessive neointimal formation when compared with BS.

Animals↗