Relationship between monitoring parameters and perinatal outcome in severe, early intrauterine growth restriction.

OBJECTIVE: To investigate whether pathological changes in the umbilical artery (UA), ductus venosus (DV) and short-term fetal heart variation are related to perinatal outcome in severe, early intrauterine growth restriction (IUGR). METHODS: This multicenter, prospective, longitudinal, observational study was carried out in the Departments of Fetal Medicine and Obstetrics in Hamburg, Amsterdam, Utrecht and London. In 70 singleton pregnancies with IUGR fetuses, delivered at 26-33 weeks of gestation because of antepartum fetal distress, short-term variation (STV) of fetal heart rate, pulsatility index of the fetal UA (UA PI) and DV pulsatility index for veins (DV PIV) were assessed at least weekly. The final measurement was performed within 24 h of delivery. Standard cut-off levels (2 SD or 3 SD, absent flow or reversed flow) were used and new cut-off levels were calculated by means of receiver-operating characteristics analysis. Adverse outcome was defined as perinatal death, cerebral hemorrhage (> or = Grade II) or bronchopulmonary dysplasia before discharge. The predictive value for adverse outcome was calculated for different cut-off levels of the monitoring parameters, adjusted for gestational age (GA), by multivariate logistic regression analysis. Data were analyzed separately for three different time blocks, namely 8-14, 2-7 and 0-1 days before delivery. RESULTS: Adverse perinatal outcome occurred in 18/70 (26%) infants. During the last 24 h before delivery DV PIV and UA PI were significantly higher and STV lower in the adverse outcome group, while 2-7 days before delivery only DV PIV was significantly higher. Adverse perinatal outcome could be predicted at 0-1 days before delivery by DV PIV at a cut-off of three multiples of the SD (odds ratio (OR) 11.3; 95% CI 2.3-57) and GA (OR 0.4; 95% CI 0.3-0.8), at 2-7 days by DV PIV at 2 SD (OR 3.0; 95% CI 0.8-12) and GA (OR 0.5; 95% CI 0.3-0.8) and at 8-14 days by DV PIV at 2 SD (OR 3.9; 95% CI 0.8-20) and GA (OR 0.5; 95% CI 0.3-0.8). Other parameters did not contribute to the multivariate model. CONCLUSIONS: DV PIV measurement is the best predictor of perinatal outcome. This measurement may be useful in timing the delivery of early IUGR fetuses and in improving perinatal outcome, even when delivery may be indicated at an earlier GA. However, as GA was also an important factor influencing outcome, with poorer outcome at earlier gestation at delivery, this hypothesis needs to be tested in a multicenter, prospective, randomized trial.     

Microvascular function in viable myocardium after chronic infarction does not influence fractional flow reserve measurements.

Fractional flow reserve (FFR) is an index of coronary stenosis severity. FFR is the ratio of hyperemic myocardial flow in the stenotic area to maximal flow in that same territory without stenosis and can be measured with a pressure wire. In patients with prior infarction, measuring FFR in infarct-related arteries may be different for 2 reasons: a smaller mass of viable myocardium depending on the stenotic infarct-related artery and greater microvascular resistance in the infarcted area than in the reference area. When microvascular resistance does not differ between the infarcted and the reference areas, FFR should equal relative flow reserve (RFR). RFR is the ratio of myocardial blood flow in the stenotic area to blood flow in a normally perfused reference area, at maximal hyperemia. H(2)(15)O PET measures myocardial flow within only the viable areas of an infarct and can be used to measure RFR. The present study assessed in patients with chronic myocardial infarction whether microvascular resistance in the infarct is different from that in the reference area. Therefore, the correlation between FFR and RFR using H(2)(15)O PET was studied. METHODS: In the catheterization laboratory, FFR was measured in the infarct-related artery and a reference coronary artery. The H(2)(15)O PET study and FFR measurements were performed on the same day in 22 patients. RESULTS: In 27 patients, the mean interval between the PET study and infarction was 3.3 y. Most patients had an anterior infarction, and the mean ejection fraction was 44%. The mean FFR and RFR values were 0.75 +/- 0.16 and 0.74 +/- 0.18, respectively. A significant correlation (r = 0.81; P < 0.0001) was found between FFR and RFR. The linear regression line was close to the line of identity. CONCLUSION: In patients with chronic myocardial infarction and a reduced ejection fraction, a good correlation was found between FFR measurements in the infarct-related artery and RFR. Because the linear regression line between FFR and RFR was close to the line of identity, one can conclude that microvascular resistance in the viable myocardium does not differ from that in the reference area.     

Free vortex ring formation in the left atrium originating in the left auricle.

An 80-year-old woman was evaluated by transesophageal echocardiography after coronary artery bypass surgery and subsequent cardioembolic stroke. In addition to spontaneous echo contrast demonstrating a counterclockwise rotating blood flow pattern, we observed free vortex ring formation in the left atrium, originating in the left auricle. To our knowledge, this is the first reported case of abnormal free vortex ring type flow pattern in the left atrium.     

Children referred for specialist care: a nationwide study in Dutch general practice.

BACKGROUND: Insight into referral patterns provides general practitioners (GPs) and specialists with a frame of reference for their own work and enables assessment of the need for secondary care. Only approximate information is available. AIM: To determine how often, to which specialties and for what conditions children in different age groups are referred, as well as how often a condition is referred given the incidence in general practice. METHOD: From data of the Dutch National Survey of Morbidity and Interventions in General Practice, 63,753 new referrals (acute and non-acute) were analysed for children (0-14 years) from 103 participating practices (161 GPs) who registered. Practices were divided into four groups. Each group of practices participated for three consecutive months covering a whole year altogether. We calculated referral rates per 1000 children per year and referability rates per 100 episodes, which quantifies the a priori chance of a condition being referred for specialist care. RESULTS: The referral rate varied by age from 231 for children under 1 year old to 119 for those aged 10-14 years (mean 159). The specialties mainly involved were ENT, paediatrics, surgery, ophthalmology, dermatology and orthopaedics. Referrals in the first year of life were most frequently to paediatricians (123); among older children the referral rate to paediatricians decreased (mean 36). Referrals to ENT specialists were seen particularly in the age groups 1-4 (71) and 5-9 (53). For surgery, the referral rate increased by age from 19 to 34. Differences between boys and girls were small, except for surgery. The highest referral rates were for problems in the International Classification of Primary Care (ICPC) chapters: respiratory (28); musculoskeletal (25); ear (24) and eye (21). Referability rates were, in general, low for conditions referred to paediatrics and dermatology and high for surgery and ophthalmology. The variation in problems presented to each specialty is indicated by the proportion of all referrals constituted by the 10 most frequently referred diagnoses: from 35% for paediatrics to 81% for ENT; for ophthalmology, five diagnoses accounted for 83% of all referrals. CONCLUSIONS: The need for specialist care in childhood is clarified with detailed information for different age categories, specialties involved and variation in morbidity presented to specialists, as well as the proneness of conditions to be referred.     

Cost-effectiveness of diagnostic imaging work-up and treatment for patients with intermittent claudication in The Netherlands.

OBJECTIVE: to determine the societal cost-effectiveness of various management strategies, including both the diagnostic imaging work-up and treatment, for patients with intermittent claudication in The Netherlands. METHODS: a decision-analytic model was used and included probability and quality of life data available from the literature. A cost-analysis was performed in a university setting in The Netherlands. Imaging work-up options included magnetic resonance angiography (MRA), color-guided duplex ultrasound, or intraarterial digital subtraction angiography (DSA) and treatment options were percutaneous transluminal angioplasty with selective stent placement if feasible or bypass surgery. Management strategies were defined as combinations of imaging work-up and treatment options. A conservative strategy with no imaging work-up and walking exercises was considered as reference. Main outcome measures were quality-adjusted life years (QALYs), lifetime costs (euro), and incremental cost-effectiveness (CE) ratios. The base-case analysis evaluated 60-year-old men with severe unilateral intermittent claudication of at least one year duration. RESULTS: the range in QALYs and costs across management strategies that considered angioplasty as only treatment option was small (maximum difference: 0.0033 QALYs and 451 euros). Similarly, the range was small across management strategies that considered angioplasty if feasible otherwise bypass surgery (maximum difference: 0.0033 QALYs and 280 euros). MRA in combination with angioplasty (6.1487 QALYs and 8556 euros) had a CE ratio of 20,000 euros/QALY relative to the conservative strategy. The most effective strategy was DSA in combination with angioplasty if feasible otherwise bypass surgery (6.2254 QALYs and 18,583 euros) which had a CE ratio of 131,000 euros/QALY relative to MRA in combination with angioplasty. CONCLUSION: the results suggest that the imaging work-up with non-invasive imaging modalities can replace DSA for the work-up of patients with intermittent claudication without a substantial loss in effectiveness and a minimal cost-reduction. Management strategies including angioplasty are cost-effective in the Netherlands but although strategies including bypass surgery are more effective, their incremental costs are very high.     

Two amino-acid substitutions in the myelin protein zero gene of a case of Charcot-Marie-Tooth disease associated with light-near dissociation.

Charcot-Marie-Tooth disease caused by mutations of the myelin protein zero gene demonstrates considerable phenotypical variability. We describe a 45-year-old female with a peripheral neuropathy with demyelinating and axonal features, pes cavus and pupillary light-near dissociation. She was heterozygous for two mutations in the myelin protein zero gene (His81Tyr and Val113Phe), both present on the same allele. Our patient shows a less severe phenotype than previously described patients with a His81Arg mutation. Multiple mutations in the myelin protein zero gene, as well as Charcot-Marie-Tooth with pupillary abnormalities have previously been described in rare instances. However, concurrent occurrence of both phenomena is a novel finding.     

Transesophageal echocardiography in pediatric patients: preliminary results

Transesophageal echocardiography was attempted in 59 pediatric patients with congenital heart disease in the operating room (n = 33) or during heart catheterization or in the intensive care unit (n = 26). Six different commercially available transducers were used with diameters ranging from 7 to 15 mm. Age ranged from 1 day to 16 years, and body weight ranged from 3.7 to 65 kg. Objectives of the study were to determine (1) minimum body weight in which transesophageal echocardiography with various probes is possible, (2) additional diagnostic value, and (3) potential applications. In three cases (one surgical and two nonsurgical) the probe could not be inserted. Minimum body weight was 17 to 20 kg for probes with a diameter of greater than or equal to 13 mm and approximately 12 kg for the 11 mm probes. A 7 mm probe, on the other hand, could be inserted easily in all patients (including a neonate) in whom transesophageal echocardiography was attempted. In 11 of 56 patients, additional diagnostic information was obtained. Thus, transesophageal echocardiography is feasible in the pediatric age group provided that special probes are used in small children. Additional diagnostic information can be obtained, and the technique is of value during cardiac surgery or balloon interventions for evaluation of the efficacy of the procedure and for monitoring ventricular function.     

Prospect for enzyme therapy in glycogenosis II variants: a study on cultured muscle cells

Summary Impairment of skeletal muscle function is the common feature of distinct clinical forms of glycogenosis type II. In the present study, muscle cultures from different patients were used to investigate the cause of clinical heterogeneity and the feasibility of enzyme replacement therapy. The activity of acid -glucosidase appears to be the primary factor in determining the extent of lysosomal glycogen storage in muscle, and thereby the clinical severity of the disease. Neutral -glucosidases do not seem influencial. Correction of the enzymatic defect was achieved in skeletal muscle cultures from patients by administration of a high-uptake form of acid -glucosidase, purified from human urine. The enzyme reaches the lysosomes, including the glycogen storage vacuoles, and the lysosomal glycogen content is reduced to control level. In normal muscle cells 20% of the total cellular glycogen pool is segregated in lysosomal compartments. This percentage is higher than in fibroblasts, which may partly explain why muscles are more prone to store glycogen. The relevance of this study for enzyme therapy is discussed.     

Construction and performance of a new catheter-tip oxygen electrode

A membrane-covered catheter-tip oxygen-electrode system is described, which gives a linear response in the P_o2 range of 0–350 mm Hg. The system is highly stable, free from drift and mechanically safe for application in man. This is accomplished by using a screw cap for fastening the membrane holder, thus preventing the loss of parts and making the electrolyte chamber really fluidtight. Insulation of the platinum wire with glass precludes the possibility of fluid-bridge contact with the silver anode beyond the measuring site at the tip.