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M Amato

Publications and source records attributed to M Amato.

At least 19 recordsLinked to original sources
PubMed1996

Effect of the stress level achieved during symptom-limited exercise technetium-99m sestamibi myocardial tomography on the detection of coronary artery disease.

BACKGROUND: The stress level achieved during exercise thallium 201 myocardial imaging may influence its sensitivity for detecting coronary artery disease (CAD). The effect of exercise adequacy on the accuracy of technetium-99m sestamibi (MIBI) imaging has not been studied. HYPOTHESIS: The study was undertaken to assess the effect of exercise level achieved on sensitivity for detecting CAD. METHODS: A consecutive series of 250 patients (mean age 60 +/- 10 years) with CAD by angiography underwent symptom-limited exercise MIBI single-photon emission computed tomography. Single-vessel CAD was found in 66 patients, double-vessel CAD in 84, triple-vessel CAD in 80, and left main disease in 20. RESULTS: No significant differences were found in sensitivities of an abnormal MIBI scan or a reversible defect among 102 patients reaching 85% of age-predicted heart rate and 148 who did not (82 vs. 89% and 66 vs. 70%, respectively, p = NS). Patients (n = 128) able to exercise < or = 6 min had a higher incidence of abnormal scans and reversible defects than 122 patients with a greater exercise duration (91 vs. 82% and 75 vs. 61%, respectively, both p < 0.05). Sensitivity of an abnormal MIBI scan for multivessel disease was greater than for single-vessel disease in patients who achieved > or = 85% of age-predicted heart rate (91 vs. 59%, p < 0.01) and in those who exercised > 6 min (89 vs. 66%, p < 0.01). No significant differences in the sensitivities of an abnormal MIBI study for multivessel versus single-vessel CAD were seen in patients achieving lower peak levels of exercise. Sensitivity of ischemic ST depression was lower than that of MIBI tomography at all levels of exercise. CONCLUSIONS: The sensitivity of exercise MIBI tomography for angiographic CAD is relatively independent of the peak heart rate achieved. Exercise duration of > 6 min is associated with a significantly higher MIBI abnormality rate than a duration of > 6 min, possibly reflecting the effect of myocardial ischemic burden on exercise ventricular function. Regardless of level of stress or its duration, exercise MIBI tomography improves the sensitivity for CAD detection compared with stress-induced ischemic ST depression.

Adult↗
PubMed1996

Dipyridamole technetium-99m sestamibi myocardial tomography in patients evaluated for elective vascular surgery: prognostic value for perioperative and late cardiac events.

Dipyridamole thallium-201 myocardial imaging can provide information regarding risk of perioperative cardiac events in patients being considered for vascular surgery. The value for this purpose of myocardial imaging with technetium-99m sestamibi (MIBI), a radiotracer with biokinetic and imaging properties different from thallium-201, has not been established. To this end the prognostic value of dipyridamole MIBI tomography for perioperative and late cardiac events was evaluated in 229 consecutive patients being considered for elective vascular surgery. Vascular surgery was done < or = 3 months after testing in 197 of these patients. Perioperative cardiac events (cardiac death, nonfatal myocardial infarction, unstable angina, or ischemic pulmonary edema) occurred in 9 (5%) patients. The rate of such events was 3% in patients with normal MIBI results, 5% in those with abnormal results, and 6% in patients with a reversible MIBI defect (both p = NS). When patients with abnormal MIBI results who had preoperative cardiac interventions (coronary revascularization or an increase in antiischemic medical therapy) were compared with with those who did not, no significant differences in the occurrence of perioperative cardiac events were found between these two groups either. A group of 172 medically treated patients who survived vascular surgery and did not have a nonfatal perioperative cardiac event was then monitored (mean 21 +/- 14 months) for the occurrence of a serious late cardiac event (nonfatal myocardial infarction or cardiac death). Event-free survival (Mantel-Cox) was significantly less in patients with abnormal studies compared with those with normal scan results. Late cardiac events occurred in 26 (15%) patients, with those having an abnormal MIBI result showing a significantly greater event rate than those with normal results (26% vs 4%, p < 0.0001). The rate of late cardiac events was 33% in patients with a reversible MIBI defect (p < 0.001) and 23% in those with a fixed defect (p < 0.03). Independent Cox multivariable predictors of increased risk of late cardiac events were a history of diabetes mellitus (relative risk [RR] 2.2, 95% confidence interval [CI] 1.0 to 4.9), an abnormal MIBI study (RR 3.7, 95% CI 1.2 to 11.4), and a reversible MIBI defect (RR 2.7, 95% CI 1.2 to 6.1). We conclude that, although its ability to assess increased perioperative cardiac risk remains uncertain, dipyridamole MIBI tomography does provide important prognostic information regarding the risk of serious cardiac events in patients having vascular surgery. The presence of an abnormal MIBI result, specifically one demonstrating a reversible perfusion defect, is associated with significantly increased risk.

Aged↗
PubMed1996

Dipyridamole technetium 99m sestamibi myocardial tomography for preoperative cardiac risk stratification before major or minor nonvascular surgery.

The value of dipyridamole technetium 99m sestamibi (MIBI) tomography for preoperative cardiac risk stratification was assessed in 285 consecutive patients being considered for nonvascular surgery. A "major" (n = 140) or "minor" (n = 89) nonvascular procedure was later done in 229 of these patients < or = 4 months after dipyridamole testing. Perioperative cardiac events (unstable angina, acute ischemic pulmonary edema, nonfatal myocardial infarction, or cardiac death) occurred in 11 (8%) patients undergoing major nonvascular surgery and 1 (1%) undergoing a minor procedure. The only clinical or scintigraphic variables associated with significantly increased perioperative cardiac risk in patients having major surgery were Goldman class > or = II, an abnormal MIBI scan, and a fixed perfusion defect. In these patients, cardiac events occurred in 1% of those who had a normal MIBI study, 14% of those with an abnormal scan (p < 0.01), 12% with a reversible MIBI defect (p = 0.29), and 17% with a fixed MIBI defect (p < 0.01). In the 60 patients whose Goldman class was > or = II, only an abnormal MIBI study and a fixed perfusion defect were associated with incremental risk of a perioperative cardiac event. The incidence of perioperative cardiac events in these patients was 4% with a normal MIBI scan, 27% with an abnormal study (p < 0.05), 24% with a reversible MIBI defect (p = 0.45), and 37% with a fixed defect (p < 0.01). Event rates were low in patients having minor nonvascular surgery; none of the 25 with a normal MIBI study and only 1 of the 64 with an abnormal scan had a perioperative cardiac event (p = not significant (NS). We conclude that dipyridamole MIBI tomography can provide important prognostic information in patients having major nonvascular surgery. A normal MIBI study indicates a low risk of perioperative cardiac events, whereas an abnormal study in patients with Goldman class > or = II undergoing major surgery is associated with significantly increased risk. The prognostic value of MIBI tomography in patients at low clinical risk undergoing minor surgery is limited.

Aged↗
PubMed1996

Influence of bilirubin on surface tension properties of lung surfactant.

AIM: To investigate the influence of bilirubin on the surface tension activity of a porcine derived (Curosurf) and synthetic (Exosurf) surfactant. METHODS: The captive bubble surfactometer at phospholipid doses of 0.5 mg/ml (low dose) and 1 mg/ml (high dose) in solutions of increasing bilirubin concentrations (0.25, 0.5, and 1.0 mg/ml) was used. RESULTS: Curosurf (without bilirubin) showed a higher surface f1p4ion activity than Exosurf, as shown by area compression of 30 (SD 0.6)% compared with 76(1.4)% at low surfactant dose and 25 (0.9)% compared with 85 (0.5)% at high dose (P < 0.01). Bilirubin showed negligible surface activity at the concentrations studied. At low phospholipid dose (0.5 mg/ml Curosurf), bilirubin increased film area compression of lipid extract surfactant from 30 (0.6)% to 55 (1.6)%, 59 (0.1)%, and 68 (0.5)% at the three studied bilirubin concentrations, respectively (P < 0.01). At high phospholipid dose (1 mg/ml Curosurf), bilirubin had the same adverse, although less pronounced, effect on film area compression of porcine lipid extract surfactant (25 (0.9)% vs 26 (0.9)%, 39 (1.3)%, and 44 (1.1)%, respectively) (P < 0.01). Using synthetic surfactant (Exosurf), with a much lower original surface activity, bilirubin did not further inhibit its surface tension properties at any of the phospholipid doses studied. CONCLUSION: These results indicate that in vitro bilirubin impairs the surface tension activity of porcine lipid extract surfactant, but does not affect synthetic surfactant activity.

Bilirubin↗
PubMed1995

Exercise technetium-99m myocardial tomography for the risk stratification of men with medically treated unstable angina pectoris.

The prognostic value of predischarge maximal exercise stress testing with technetium-99m sestamibi (MIBI) myocardial tomography was assessed in 126 consecutive men hospitalized with a diagnosis of unstable angina pectoris who were medically stabilized. None had coronary revascularization for < or = 6 months after testing. Over a mean follow-up of 12 +/- 7 months (range 1 to 29), 35 patients (28%) had a cardiac event--nonfatal acute myocardial infarction (n = 6), cardiac death (n = 5), or rehospitalization for unstable angina (n = 24). Any type of cardiac event occurred in 12% of patients with normal MIBI scans, compared with 39% of those with an abnormal MIBI scan (p < 0.001) and 60% of those with a reversible perfusion defect (p < 0.0001). Only 2% of patients with normal scans had either a nonfatal myocardial infarction or cardiac death, compared with 14% of those with abnormal MIBI scans (p < 0.05) and 25% with a reversible defect (p < 0.001). A fixed perfusion defect was not associated with increased cardiac risk. With use of multivariable Cox proportional-hazards modeling, the only scintigraphic variable with independent predictive value was the presence of a reversible MIBI defect, with a relative risk of 3.8 (95% confidence interval 1.6 to 8.6, p < 0.05) for any cardiac event, and 19.2 (95% confidence interval 2.2 to 167.0, p < 0.05) for a nonfatal myocardial infarction or cardiac death. Cardiac event-free survival was also significantly decreased in patients with a reversible perfusion defect (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Mechanisms of bilirubin toxicity.

Possible mechanisms of bilirubin toxicity on the brain and lung were studied in animal experiments and in vitro. The uptake of tyrosine as precursor of dopamine in rat synaptosomes was evaluated to study the role of different bilirubin concentrations on synaptic neurotransmission. The results of this study show a statistically significant correlation between bilirubin levels and tyrosine uptake, supporting the hypothesis that the effect of bilirubin on neuronal excitability is dose-dependent. Concerning bilirubin toxicity on the lung, we studied the effect of different bilirubin concentrations on surface activity of modified natural surfactant (Curosurf) and synthetic surfactant (Exosurf), both in current clinical use for treatment of neonatal respiratory distress syndrome. Surface activity of Curosurf and Exosurf was investigated with the captive bubble surfactometer. The results of this study show that bilirubin impairs, in vitro, the surface tension activity of natural surfactant in a dose dependent manner and has no effect on surface tension activity of artificial surfactant. These data suggest that bilirubin interferes with surfactant proteins SP-B and/or SP-C, thus impairing surfactant activity at the air-liquid interface. We conclude that bilirubin shows its toxic effect reacting with different biological systems in a dose-dependent fashion.

Animals↗
PubMed1995

Prognostic value of predischarge dipyridamole technetium 99m sestamibi myocardial tomography in medically treated patients with unstable angina.

Recently developed unstable angina clinical practice guidelines have recommended risk stratification with dipyridamole thallium-201 myocardial imaging in patients at "intermediate" pretest clinical risk who cannot exercise maximally. The prognostic value of predischarge dipyridamole technetium 99m sestamibi (MIBI) tomography has not been assessed in this clinical setting. To this end, 128 medically treated patients with unstable angina at intermediate pretest clinical risk underwent follow-up for 16 +/- 11 (mean +/- SD) months after predischarge intravenous dipyridamole MIBI tomography. An abnormal MIBI scan result was present in 99 patients (77%), of whom 47 had one or more reversible and 76 had one or more fixed perfusion defects. Cardiac events occurred in 68 (53%) patients after dipyridamole testing: recurrent unstable angina (n = 36), nonfatal acute myocardial infarction (n = 6), or death (n = 26). A cardiac event occurred in 10% of patients with normal MIBI tomography results compared with 69% of those with abnormal results (p < 0.01). Event rates associated with specific perfusion defects were similar (reversible = 68%; fixed = 71%) and were greater than rates in patients without defects (both p < 0.05). Clinical variables associated with increased risk of cardiac events by univariate analysis included a history of congestive heart failure, prior myocardial infarction, and diabetes mellitus (all p < 0.05). Independent multivariable predictors (Cox proportional hazards model) of any cardiac event were an abnormal result of MIBI scan (relative risk [RR] = 4.3, 95% confidence interval [CI] 1.5 to 12.0) and a reversible (RR = 1.8, 95% CI 1.1 to 2.9) or a fixed perfusion defect (RR = 2.9, 95% CI 1.6 to 5.4).(ABSTRACT TRUNCATED AT 250 WORDS)

Angina, Unstable↗
PubMed1995

Immunoglobulin subclass concentration in preterm infants treated prophylactically with different intravenous immunoglobins.

The most immature infants have critically low concentrations of all immunoglobulin G (IgG) subclasses, associated with a higher risk for pyogenic, respiratory, and meningeal infection. Selective IgG subclass deficiency is an established indication for intravenous immunoglobulin (IVIG) substitution. However, considering that therapeutic efficacy of IVIG is dependent on its pharmacokinetics, we studied peak and trough IgG subclass serum levels during the neonatal period (28 days) in a group of 34 healthy preterm babies (30.2 +/- 2 weeks gestational age (GA) and 1065 +/- 210 g birthweight (BW) treated prophylactically with three daily standard doses of two different IVIG preparations: Sandoglobulin (SG) (0.5 g/kg/day) and Pentaglobin (PG) (5 mL/kg/day). IgG subclass levels were assayed by radioimmundiffusion (RID) before treatment (day 1) and at days 3, 5, 7, 14, and 28 of life. Statistical analysis was performed by paired t test. In the first week of life only (days 3, 5, 7), for both IVIG preparations, subclass levels were higher than pretreatment values: IgG1, 4.6 +/- 1.7 versus 5.6 +/- 1.6 g/L; IgG2, 1.6 +/- 0.8 versus 2.1 +/- 0.6 g/L; IgG3, 0.2 +/- 0.7 versus 0.3 +/- 0.1 g/L; IgG4, 0.3 +/- 0.1 versus 0.9 +/- 0.1 g/L (p < 0.05). During this time (7 days) IgG2 levels were higher in the SG group and IgG4 was higher in the PG group (p < 0.05). This study shows pretreatment IgG subclass levels 14 days after treatment and different patterns, depending on the used preparation. We conclude that prospective clinical trials should include the study of target serum levels and timing of IVIG administration not only for IgG but also for IgG subclasses.

Bacterial Infections↗
PubMed1995

Effect of acidosis on bilirubin-lipid extract surfactant interaction.

The risk of bilirubin toxicity in newborn infants with respiratory distress syndrome and hyperbilirubinemia may depend on many factors including pH of the system. Biophysical activity and inhibition characteristics were studied in vitro for lipid extract surfactant (Curosurf, 0.25 mg/ml phospholipids), bilirubin (1.0 mg/ml dissolved in NaOH) and mixed solutions at different pH ranging from 5.0 to 7.4. It was found that unconjugated bilirubin modifies surface tension behavior of lipid extract surfactant films. Maximum and minimum surface tension levels were significantly higher in mixed solutions compared to experiments using pure Curosurf independently from pH. Film area compression for pure Curosurf was not influenced by pH and varied between 22 +/- 4% at pH 5.0 and 23 +/- 9% at pH 7.4. Adding bilirubin to lipid extract surfactant, area compression to achieve minimum surface tension increased significantly to 83 +/- 4% at pH 5.0 and 85 +/- 4% at pH 7.4 (p < 0.01). Bilirubin alone showed negligible surface activity independently from pH (83 +/- 7% at pH 5.0 and 78 +/- 9% at pH 7.4) (p > 0.5). We conclude that bilirubin has a detrimental effect on the surface tension properties of lipid extract surfactant in vitro and that this interaction is independent from pH. These data suggest no influence of acidosis on alveolar surfactant system in babies with respiratory distress syndrome and hyperbilirubinemia.

Adsorption↗
PubMed1995

Regional metabolic assessment of human brain during development by proton magnetic resonance spectroscopy in vivo and by high-performance liquid chromatography/gas chromatography in autopsy tissue.

To study the course of regional metabolite concentrations during early brain development, we measured in vivo metabolites [N-acetyl-aspartate (NAA), choline-containing compounds, and myoinositol (M-Ino)] in the precentral area of the cerebrum by short echo-time single volume proton magnetic resonance spectroscopy and compared in vivo established spectroscopic data with classic chromatographic data (HPLC) on age-corresponding autopsy tissue in different regions of the brain. In autopsy tissue, regional (frontal lobe, precentral area, basal ganglia, thalamus) and age-dependent differences of the concentration of creatine, NAA, and M-Ino were determined. In vivo measurement of NAA by proton magnetic resonance spectroscopy shows a significant increase of NAA by increasing postconceptional age. M-Ino shows a weak correlation and a nonsignificant decrease with increasing postconceptional age. Choline shows no age-dependent changes. Creatine concentrations measured by HPLC in different regions of the developing brain at autopsy showed an age-dependent increase that was identical for the left and right side and similar for the precentral area and frontal lobe and more pronounced for the basal ganglia and thalamus. Comparison of the results obtained by the two methods shows agreement for the age-dependent changes and the absolute concentration of M-Ino. NAA determined in autopsy tissue by HPLC is significantly lower than that measured in vivo by proton magnetic resonance spectroscopy. A comparison of the concentrations measured by HPLC in frontal lobe, basal ganglia, and thalamus with the results obtained from the precentral area showed significant regional differences in all measured metabolites. These results define important age-dependent changes detected with both methods and further indicate limitations of both methods that have to be considered when presenting absolute concentration values.

Age Factors↗
PubMed1994

Second messenger formation altered by different dialysis membranes in human leukocytes.

A number of agents stimulate transmembrane cell-signaling in different cell types through the formation of the second messenger diacylglycerol (DAG) which activates protein kinase C (PKC). The aim of this study was to investigate phospholipase C activation, DAG formation, and cellular adhesion to dialysis membranes after simulated dialytic treatment of either human leukocytes or clonal hematopoietic cells. Cells were circulated for 60 minutes in a closed-loop dialysis system using three different dialyzers: cuprophan (CU), polysulphone (PS), and AN69 (PAN). Another cell aliquot was left within the dialyzers without circulation. Samples were taken at different time intervals and cells counted. Cells were labeled with tritiated glycerol overnight, and DAG was measured by thin-layer chromatography. Our data showed that cells tended to adhere with more efficiency to CU than to the synthetic dialyzers. Circulation in the in vitro dialysis circuit resulted in the rapid (5 min) formation of [3H]DAG (CU 1.95-; PS 1.34-; PAN 1.24-fold increase over untreated cells). The DAG level peaked at 15 to 30 minutes and remained constant thereafter (CU 1.70; PS 1.96; PAN 1.66). When we measured DAG formation in cells that had been kept in the dialyzers without circulation, we found that cells exposed to CU showed a much higher and rapid activation than those exposed to PS or PAN, as if CU per se was able to activate early cell signaling (CU 1.95-; PS 0.97-; PAN 1.09-; DAG, -fold increase over control).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1994

Differential leukocyte count in babies treated with natural surfactant.

The potential of exogenous replacement therapy in surfactant-deficient states such as neonatal respiratory distress syndrome (RDS) is an area of intense clinical interest today. At present, a fundamental problem with any type of exogenous surfactant is the uncertainty about potential effects on physiological defense mechanisms, such as differentiation and mobilization of peripheral leukocytes. Considering that newborn infants with proven bacterial infections have abnormal values of segmented (neutrophil) and nonsegmented (band) polymorphonuclear leukocytes, we studied 42 placebo- versus Curosurf-treated babies with severe RDS. Differential white blood cell (WBC) count was serially performed before and after treatment during the first days of life. The statistically significant increase in the proportion of bands in surfactant-treated babies did not coincide with clinical and bacteriologic evidence of possible infection. Some molecular interaction mechanisms influencing immature to mature WBC ratio are supposed. Among a variety of influences on the leukocyte count, surfactant replacement therapy needs to be considered for proper interpretation of hematologic data in babies treated for RDS.

Bacterial Infections↗
PubMed1994

Ethamsylate and lung permeability in ventilated immature newborn rabbits.

The leakage of proteins in the immature neonatal lung can reduce the effect of exogenous surfactant. The effect of ethamsylate, a more specific prostaglandin inhibitor than indomethacin and aspirin-like drugs, on alveolar albumin leak was studied in a group of 27 immature newborn rabbits (gestational age 27 days). A pilot study was carried out using 4 animals and low-dose ethamsylate (10 mg/kg). A second group of animals (n = 12) received at birth, by intravenous injection, ethamsylate (50 mg/kg) and 10% human albumin (7 ml/kg). Animals not receiving ethamsylate (n = 11) served as control group. After 30 min of artificial ventilation with standard tidal volume (10 ml/kg) the lungs were lavaged and the amount of human albumin in lung lavage fluid was determined by immunodiffusion. No statistically significant differences were found in lung-thorax compliance and vascular to alveolar albumin leak between ethamsylate-treated animals and controls (p > 0.5). However, there was a statistically significant negative correlation between protein leak and lung compliance (r = -0.41; p < 0.04). These results suggest no direct influence of early ethamsylate administration on neonatal lung permeability in the immature neonate confirming that lung permeability is inversely related to compliance.

Animals↗
PubMed1993

Serial IgG and IgM serum levels after infusion of different Ig-preparations (IgG or IgM-enriched) in preterm infants.

Intravenous administration of Immunoglobulin (IVIG) has been used for prevention or treatment of neonatal sepsis. However, therapeutic efficacy of IVIG is dependent on pharmacokinetic factors. There have been no comparative studies in neonates between licensed IgG and IgM enriched preparations. The aim of this study was to investigate serial IgG and IgM serum levels during the neonatal period in two groups of non-septic, preterm infants treated prophylactically with IVIG. Twenty-two very low birth weight (VLBW) patients (1001-1500g) (gestational age 31.8 +/- 2.0 weeks and 1265 +/- 245g birth weight) and 12 extremely low birth weight (ELBW) patients (< 1000g) (gestational age 28.6 +/- 2.5 weeks and 910-85g birth weight) received at random three standard doses of Sandoglobulin (SG) (0.5 g/kg/day) or IgM enriched Pentaglobin (PG) (5 ml/kg/day). IgG and IgM concentrations were assayed by rate nephelometry before treatment and at day 3, 5, 7, 14 and 28 of life. At any time IgG levels were higher in the SG-VLBW group (p < 0.01), no difference being observed in the ELBW group (p > 0.5). IgM levels were higher at day 3 and 5 in the PG-VLBW group and until day 7 in the ELBW group (p < 0.01). This study indicates a wide range of IgG and IgM kinetics in the healthy premature and suggests frequent monitoring of immunoglobulin serum levels during efficacy studies.

Humans↗
PubMed1993

Impact of prematurity and intrauterine growth retardation on neonatal hemorrhagic and ischemic brain damage.

Low birth weight and intrauterine growth retardation are well-recognized risk factors for increased mortality, morbidity and poor neurologic outcome. Risk assessment is different considering true preterm (appropriate-for-gestational-age, AGA) or growth-retarded (small-for-gestational-age, SGA) infants. Therefore, we carried out a study on the incidence of hemorrhagic (peri-intraventricular hemorrhage, PIVH) and ischemic (periventricular leukomalacia) brain lesions in two groups of AGA and SGA very-low-birth-weight (VLBW) infants. In the study period (1987-1990), 111 VLBW babies (< 1,500 g body weight) were serially studied at days 1, 3 and 7 and weekly until discharge by cerebral ultrasonography (ATL, MK 4, 7.5 MHz). 57 were VLBW-AGA babies (mean gestational age 28 weeks, mean body weight 1,106 g). 54 were VLBW-SGA babies (mean gestational age 31 weeks, mean body weight 990 g). PIVH was graded according to the system of Papile et al. Periventricular leukomalacia was defined as an echodensity (> 3 mm) adjacent to the lateral border of the ventricular body. We noted a higher incidence of PIVH in the AGA group (36.8%) than in SGA babies (18.5%; p < 0.01, Fisher test). The AGA subgroup < 1,000 g body weight had 72.2% PIVH compared to AGA babies > 1,000 g (20.5%; p < 0.01). The same relationship was observed in SGA babies (34.8% in < 1,000 g and 6.4% in > 1,000 g babies). Ischemic brain lesions (periventricular leukomalacia) were equally distributed between AGA and SGA babies (10.5 vs. 3.7%, p > 0.5) independently of body weight category.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain Damage, Chronic↗
PubMed1993

Influence of perinatal risk factors on the involution of the irido-pupillary membrane.

The aim of this study was to assess the influence of common perinatal risk factors on the disappearance of the anterior vascular capsule of the lens (AVCL). Direct ophthalmologic examinations were performed on 75 neonates (27 to 35 weeks gestational age) in the first 24 hours after birth, using the degree of involution of the AVCL to estimate gestational age in high risk pregnancy. Our results show that the gradual disappearance of the AVCL is not influenced by perinatal risk factors, such as maternal preeclampsia, prenatal administration of steroids, neonatal infection and low birth weight, confirming the clinical value of this test in the assessment of gestational age in high risk babies.

Female↗
PubMed1993

[Randomized study comparing mitral valve replacement with and without preservation of mitral ring chordae tendinae papillary continuity].

PURPOSE: To demonstrate the importance of the preservation of mitral annulus-chordae tendineae-papillary muscles continuity in mitral valve replacement. METHODS: We studied 21 patients who were submitted to mitral valve replacement, divided in two randomized groups: group 1, 12 cases who undergone mitral valve replacement, with preservation of the posterior leaflet and correspondent chordae tendineae; and group 2-9 cases who undergone conventional mitral valve replacement, excising the mitral valve apparatus. The left ventricular function was studied both, in the pre and post operative period, by echocardiography, cardiac catheterization, and radioisotopic study. The statistical analysis was done by the Wilcoxson's test. RESULTS: There were no early post operative deaths. Analyzing the results of the ejection fraction by the radioisotopic study we found a significant difference (p = 0.03) between the percentual decrease of the two groups. The results of the fractional shortening were higher in group 1 than in group 2, however not significant. The left ventricular diastolic diameters average was lower in group 1 than in group 2, so as the left atrium diameter. We found a decrease in left ventricular end-diastolic pressure in group 1, however there was an increase in group 2, by the cardiac catheterization. There was a proportional increase in group 1 both in lung artery and lung capillary pressures. There was a significant difference (p = 0.05) between the average values of right ventricular diastolic pressure. CONCLUSION: There is better preservation of left ventricular function in group 1.

Adult↗