Artery Diastolic Flow Research Articles

Successful thrombolysis of renal allograft venous thrombosis – A case report

Renal allograft venous thrombosis is a rare but catastrophic complication resulting in graft failure. A 55-year-old male underwent live related renal transplantation. Donor's right kidney was placed in recipient's left iliac fossa. Graft renal artery was anastomosed to the left internal iliac artery. Graft renal vein was anastomosed to the left external iliac vein in a side to side fashion. He was discharged with a serum creatinine of 0.9 mg. Four weeks after transplantation patient was readmitted with anuria for 6 h and swelling of left leg for 1 day. Doppler study showed extensive venous thrombosis extending from left femoral, external iliac veins with total occlusion of allograft vein. Renal arterial diastolic flow was absent. Blood urea was 36 mg/dl and creatinine was 2.2 mg/dl. A fogarty's catheter was inserted in the popliteal vein and venogram was performed to outline the extent of thrombus. Thrombosuction followed by In situ thrombolysis with streptokinase and heparin were carried out. His renal parameters and urine output dramatically improved following our intervention. He was discharged with the creatinine of 0.8 mg/dl. Salvage of the allograft in renal vein thrombosis is possible if early diagnosis and aggressive thrombolytic therapy are instituted.

Acute Antibody-mediated Rejection Possibly Due to Anti–human Leukocyte Antigen DQB1 Antibodies after Renal Transplantation – Case Report

A 61-year-old Japanese woman, who had undergone hemodialysis because of chronic glomerulonephritis, received a living renal transplant from her ABO blood type–compatible spouse. HLA typing of A, B and DRB showed 3/6 mismatches. Complement-dependent cytotoxicity crossmatches, HLA antibody screening with the use of flow panel reactive antibody (PRA), and flow cytometry crossmatches (FCXM) were all negative. Tacrolimus, mycophenolate mofetil, methylprednisolone (MP), and basiliximab induction were used as the standard immunosuppressive therapy. After renal transplantation, her serum creatinine level favorably decreased, but urine output was not sufficiently obtained, contrary to our expectations. Doppler sonography revealed disappearance of diastolic arterial flow on postoperative day 2. The episode biopsy showed acute antibody-mediated rejection (AMR) based on the current Banff classification, although FCXM and flow PRA were still negative. To determine the cause of acute AMR, we expanded the HLA typing at high resolution levels to Cw, DQB1, and DPB1. Retrospective analysis of perioperative sera demonstrated the presence of low levels of donor-specific HLA IgG and moderate levels of IgM antibody against DQB1 before transplantation. There was an elevation of IgM antibody at the time of rejection, whereas IgG antibody showed no remarkable change. AMR was successfully treated with plasma exchange, low-dose intravenous immunoglobulin, high-dose intravenous MP pulse, and rituximab.

Effect of Branch Pulmonary Artery Stenosis on Right Ventricular Volume Overload in Patients With Tetralogy of Fallot After Initial Surgical Repair

Right ventricular (RV) volume overload secondary to pulmonary regurgitation is common in patients after initial repair of tetralogy of Fallot (TOF) and is associated with adverse long-term outcomes. The objective of the present study was to determine the effect of branch pulmonary artery stenosis on the RV volume in patients with repaired TOF. We reviewed 178 cardiac magnetic resonance imaging studies in patients with repaired TOF. We defined bilateral stenosis as a Nakata index of ≤200 mm(2)/m(2) and concordant branch pulmonary artery cross-sectional area, unilateral stenosis as 1 branch pulmonary artery cross-sectional area ≤100 mm(2)/m(2) and 1 branch pulmonary artery cross-sectional area >100 mm(2)/m(2), and restrictive physiology as prograde main pulmonary artery diastolic flow. Of the 178 patients, 20 (11%) had bilateral stenosis, 47 (26%) unilateral stenosis, and 111 (63%) had no stenosis. The RV end-diastolic volume was lower in patients with bilateral (125 ± 27 ml/m(2)) or unilateral (131 ± 43 ml/m(2)) stenosis than in those without stenosis (149 ± 35 ml/m(2), p = 0.021 and p = 0.019, respectively). The main pulmonary artery regurgitant fraction was greater in patients without stenosis (47%, range 2% to 69%) than in those with bilateral (33%, range 9% to 59%; p = 0.009) or unilateral stenosis (40%, range 0% to 71%; p = 0.033). Restrictive physiology was more common in patients with bilateral (13 of 15, 87%) or unilateral (21 of 38, 55%) stenosis than in those without stenosis (28 of 85, 33%; p <0.001 and p = 0.017, respectively). In conclusion, in patients with repaired TOF, bilateral and unilateral branch pulmonary artery stenosis was associated with a greater main pulmonary artery regurgitant fraction and smaller RV end-diastolic volume than those in patients without stenosis, likely owing to the development of restrictive physiology. Branch pulmonary artery stenosis might effectively delay the referral for pulmonary valve replacement.

Renal dialysis, diabetes and iugr: delivery and peripartum care

A woman with Type I diabetes presented at 6+0/40 with a history of severe retinopathy, hypertension and nephropathy. A previous combined renal and pancreatic transplant had failed necessitating haemodialysis five...

Indomethacin Impairs Coronary Perfusion in Infants with Hemodynamically Significant Ductus Arteriosus

Background: A haemodynamically significant ductus arteriosus (HSDA) is commonly associated with morbidity in preterm infants. Aim: To study the effect of the first dose of indomethacin on coronary blood flow in preterm neonates diagnosed with an HSDA. Method: A prospective observational echocardiographic study was performed on preterm infants. A single study dose of intravenous indomethacin (0.1 mg/kg) was administered over 1 h. Serial echocardiography was performed before and after indomethacin treatment to study the effect on coronary artery perfusion and cardiovascular performance. Results: Eighteen infants born at a median gestation of 25.8 (24.2, 28.1) weeks and a birth weight of 773 g (704, 1,002) were evaluated. The median age at indomethacin administration was 7.5 days (4, 17). There was no significant change in arterial pressure or ventilatory indices. Left anterior descending artery diastolic velocity and time integral declined from 0.3 ± 0.1 and 3.19 ± 1.2 m/s to 0.22 ± 0.08 and 2.01 ± 0.9 m/s, respectively, within 10 min of completion of infusion. These indices showed partial recovery when reassessed after 60 min. There were no changes in left ventricular output or transductal flow. Conclusions: Intravenous indomethacin was followed by a decline in coronary arterial diastolic blood flow.

Intraluminal Pressure in a Uterine Tamponade Balloon Is Curvilinearly Related to the Volume of Fluid Infused

We studied the effect of incremental infusion of fluid volume in a tamponade balloon on intraluminal pressure and uterine blood flow. Following placental delivery, a tamponade balloon was inserted into the uterus and incrementally inflated. Intraluminal pressure was measured at incremental volumes. Ultrasound was used to determine positioning of the catheter, uterine wall thickness, and uterine artery velocity waveforms in eight patients. Pressure-volume relationship was estimated by regression analysis. Significance was p < 0.05. There was a significant exponential curvilinear relationship between balloon pressure and infused volume at the maximum volume for each subject ( R = 0.64, p = 0.01). Doppler ultrasound showed that at or above 1000 mL inflation volume, 5/6 patients (83%) showed reversal of uterine artery diastolic flow. At maximal inflation volume, all of the patients with reversed diastolic flow had intraluminal pressure less than systolic blood pressure. Intraluminal pressure increases curvilinearly as volume of an intrauterine tamponade balloon is increased. The mechanism of action of tamponade balloons is likely related to a reduction in uterine artery perfusion pressure. Whether this is the result of direct compression of the artery in the lower segment or due to wall conformational changes is not clear.

222 Second Course of Ibuprofen for Pda: Comparison of 10-5-5 Vs 20-10-10 Mg/Kg in Inborn Infants &lt; 28 Wks Ga

Background and aims: Recent pharmacological data suggest increased ibuprofen doses for treating patent ductus arteriosus (PDA). We evaluated the effectiveness and tolerance of a double dosed second ibuprofen course in our population. Methods: In our unit PDA management relies on systematic and repeated echocardiographic exams seeking strict treatment criteria (ductal diameter, left atrium/aortic root, left pulmonary artery diastolic blood flow). Persistent echocardiographic criteria after a first ibuprofen course induce a second course if not contra-indicated. We conducted a monocenter retrospective study by comparing two time periods: November 2004 to March 2006 and April 2006 to November 2009 where the second ibuprofen course doses respectively were 10-5-5 (IBU1) and 20-10-10 (IBU2) mg/kg. Baseline characteristics, treatment incidence, ductal closure and complications were compared between IBU1 and IBU2. Term-based subgroup analysis was performed (< or ≥ 26 wks GA). Results: IBU1 and IBU2 populations were comparable. Ductal closure was more frequent for IBU2 (23/55,42%) than for IBU1 (3/23,13%) (p=0,02). Subgroup analysis confirmed this result only for infants ≥ 26 wks GA. Incidence of mortality and common morbidities were comparable between IBU1 and IBU2. Among infants < 26 wks GA we observed a higher, although not significant, incidence of “death or BPD” for IBU2 vs IBU1 (37% vs 9%). Conclusions: This is the largest report of increased ibuprofen doses in infants < 28 wks GA with systematic echocardiographic assessment. In this study risk/benefit balance supports the use of a double-dosed second course of ibuprofen for PDA treatment only in infants ≥ 26 wks GA.

636 Quantified Evaluation of the Ductus Arteriosus

Introduction: We evaluated and quantified all ductal scans requested for predefined clinical signs and determined associations between clinical signs, ultrasound parameters and hemodynamic significance (HSDA) defined as ductal diameter (DAd) > 1.5 or >2.0 mm. Methods: Clinical signs were scored as mild (murmur, wide pulse pressure, hyperactive precordium), respiratory (difficulties to wean from or increase in respiratory support) or serious (hypotension, pulmonary edema or haemorrhage, congestive heart failure). Scans included central blood flow, DAd, ductal maximum velocity (Vmax), left pulmonary artery diastolic flow velocity (LPAd), LA/Ao ratio and flow pattern in the descending Aorta (DAo). Results: Eighty scans in 48 patients were analysed. Median (range) gestational age was 26 (23-31) weeks, postnatal age 7 (1-60) days. No associations were found between clinical signs and DAd > 1.5 or 2.0 mm. A murmur was best correlated with Vmax (Pearson 0.52, p 0.000). Hypotension and pulmonary haemorrhage were correlated with a larger ductal diameter (Pearson 0.34, p 0.002 and 0.40, p 0.000). A DAd > 1.5 mm was associated with higher LPAd, LA/Ao ratio and LVO (mean difference 15 cm/s; 95%CI 8 to 23, 0.24; 95%CI 0.12 to 0.36, 93 ml/kg/min; 95%CI 30 to 156 respectively). A DAd > 2.0 mm was associated with a lower Vmax (mean difference -95 cm/s; 95%CI -53 to -136) and more cases with reverse flow in the DAo (5% vs 55%). Conclusion: Clinical signs cannot predict ductal size. A DAd >1.5 is associated with known ultrasound parameters, a DAd >2.0 only with Vmax and DAo pattern.

OC07.05: Incidence and clinical implications of unintended septostomy after fetoscopic laser therapy for twin–twin transfusion syndrome

Objectives: Fetoscopic SLP improves outcome in TTTS by promoting resolution of cardiovascular (CV) manifestations. The time course and pattern of disease regression is unknown. We sought to investigate the nature of CV disease regression after SLP by analysis of individual cardiovascular elements through application of the CHOP score for TTTS. Methods: The CHOP score is a fetal echo derived system for detailed CV characterization of TTTS. Elements of the Score include 4 domains in the recipient: 1) ventricular characteristics of dilation, hypertrophy, systolic dysfunction, 2) atrioventricular valve (AV) regurgitation, 3) diastolic properties of Doppler AV inflow (double or single peak), ductus venosus, and umbilical venous flow, 4) right ventricular outflow tract obstruction (RVOTO) as assessed by pulmonary artery measuring smaller than aorta or pulmonary stenosis/atresia; and in the donor, evaluation of umbilical artery diastolic flow. In 32 twin pairs individual elements of the Score as well as myocardial performance indices (MPI) were measured at 1 day and 1 week after SLP and compared to pre-op values using paired t-test. Results: Overall score was unchanged at 1 day (pre-op 6.6 + 4.0 vs. 6.0 + 3.8, P = NS) but significantly improved by 1 week (4.2 + 4.1, P < 0.001) after SLP. At 1 day, there was no improvement in systolic or diastolic parameters and AV regurgitation worsened, however there was slight improvement in RVOTO (P < 0.05) and recipient RV and LV MPI (P = 0.02). At 1 week, improvements in ventricular dilation (P = 0.01), hypertrophy (P = 0.01) and all of the diastolic parameters were noted, with further improvement in RVOTO (P = 0.002) and recipient RV and LV MPI (P < 0.01). Systolic performance and AV regurgitation did not improve. Conclusions: Minimal improvement is seen 1 day after SLP, however diastolic CV elements, but not systolic, improve substantially at 1 week. Acute diastolic relaxation of the recipient right ventricle after SLP may improve filling and result in an increase in pulmonary artery diameter.

Selective intrauterine growth restriction in monochorionic twins: pathophysiology, diagnostic approach and management dilemmas

Selective intrauterine growth restriction (sIUGR) in monochorionic twins is associated with a substantial increase in perinatal mortality and morbidity for both twins. Clinical evolution depends on the combination of the effects of placental insufficiency in the IUGR twin with inter-twin blood transfer through placental anastomoses. Classification of sIUGR into types according to the characteristics of umbilical artery diastolic flow in the IUGR twin permits the differentiation of clinical and prognostic groups. sIUGR type I has normal diastolic flow and relatively good outcome. Type II is defined by persistently absent/reverse end-diastolic flow and is associated with a high risk of intrauterine demise of the IUGR twin and/or very preterm delivery. Type III is defined by the presence of intermittent absent/reverse end-diastolic flow (iAREDF), and is associated with 10-20% risk of unexpected fetal demise of the smaller twin and 10-20% risk of neurological injury in the larger twin. The management strategy for sIUGR with abnormal umbilical artery Doppler (types II and III) remains a challenge, and may include elective fetal therapy or close surveillance with fetal therapy or elective delivery in the presence of severe fetal deterioration. Small clinical series reporting the use of cord occlusion or laser therapy in severe cases suggest that the outcome of the larger twin might be improved. There is probably no single optimal strategy, since decisions will ultimately be influenced by the severity of IUGR, gestational age, parents' wishes and technical issues.

Two-Dimensional and Doppler Echocardiography Reliably Predict Severe Pulmonary Regurgitation as Quantified by Cardiac Magnetic Resonance

The grading of pulmonary regurgitation (PR) severity by two-dimensional (2D) and Doppler echocardiography is not standardized. Cardiovascular magnetic resonance imaging is the clinical gold standard for PR quantification. The purpose of this study was to determine the best 2D and Doppler echocardiographic predictors of severe PR. Thirty-six patients with tetralogy of Fallot or pulmonary valve stenosis with prior pulmonary valvuloplasty or transannular or subannular patch repair underwent 2D and Doppler echocardiography and cardiovascular magnetic resonance. Two-dimensional and Doppler echocardiographic measurements used to predict severe PR included diastolic flow reversal in the main or branch pulmonary arteries, PR jet width > or = 50% of the pulmonary annulus, PR pressure half-time < 100 ms, and PR index < 0.77. With the exception of PR index, all indices were significant independent predictors of severe PR. The best univariate predictor of severe PR was branch pulmonary artery diastolic flow reversal. Two-dimensional and Doppler echocardiography reliably identified severe PR in this cohort.

Ophthalmic Artery Blood Flow in Very-Low-Birth-Weight Preterm Infants

To evaluate normal blood flow velocity and Doppler indices of the ophthalmic arteries from birth to hospital discharge of inborn infants at birth weights between 500 and 1500 g and gestational age <or=32 weeks. A longitudinal prospective study with Doppler ultrasound was conducted in both eyes at 24 hours, 7 and 28 days, and hospital discharge for systolic and diastolic velocities, pulsatility, and resistance indices. Retinopathy of prematurity stage 2 and higher, peri-intraventricular hemorrhage grades 3 and 4, and death were excluded. The authors studied 46 very-low-birth-weight infants (92 eyes; birth weight, 1215 +/- 202 g; gestational age, 30.4 +/- 1.3 weeks). Both eyes had similar Doppler findings at each study interval. Systolic velocity increased significantly from birth to hospital discharge (P = 0.001; right eye, 17.85 +/- 5.3 cm/s and 23.18 +/- 4.88 cm/s; left eye, 17.78 +/- 5.19 cm/s and 23.51 +/- 5.63 cm/s), as did diastolic velocity (P = 0.02; right eye, 6.17 +/- 1.13 cm/s and 6.76 +/- 1.12 cm/s; left eye, 6.34 +/- 1.26 cm/s and 6.9 +/- 1.53 cm/s). Pulsatility and resistance indices did not change during the entire period. There is a typical pattern of ophthalmic artery systolic and diastolic blood flow velocities, and pulsatility and resistance indices during the neonatal period in very-low-birth-weight infants.

Idiopathic normal pressure hydrocephalus: Thoughts on etiology and pathophysiology

Idiopathic normal pressure hydrocephalus (NPH) remains a mysterious entity, with several gaps in our understanding, despite intensive research. The current theory of its etiology is diminished vascular compliance with redistribution of vascular pulsations. The manifestations of NPH can be explained by the compression of parenchyma and vessels and the accumulation of toxic metabolites in the cerebrospinal fluid (CSF) and in the brain parenchyma. The author believes that NPH is caused by repetitive disruption of the normal propagation of ventricular systole, due to chronic derangements of cerebral arterial hemodynamics. The result is functional obstruction of the inter- and/or intra-ventricular CSF flow, leading to active and progressive ventriculomegaly. The author suggests that transependymal migration of CSF disturbs the osmotic balance of the periventricular zones, contributing to the cellular and axonal damage and dysfunction in NPH. The hypothesis can be tested with computational fluid dynamics and animal models. Based on established knowledge and on this hypothesis, the author proposes a multistep therapeutic scheme for NPH. First the patient's CSF is traded for a hypotonic CSF-like solution. The "clean" CSF, via transependymal migration, will sweep away some of the debris from the parenchyma and it will rehydrate cells and axons in the periventricular areas. Subsequently, vasodilatory drugs can be infused in the ventricles in order to reach compressed vessels, again via the transependymal route. Ventricular drainage can then proceed as per standard practice. The final step is the use of oral antihypertensive medications to decrease the arterial systolic blood pressure and simultaneously increase the arterial diastolic blood flow. The goal is to enhance protection of the periventricular tissues from pressure and osmotic loads. The antihypertensive regimen may be useful in two more groups of patients with NPH: those who are not surgical candidates and those in an early or subclinical phase of the disease.

A case of accelerated acute rejection after ABO‐compatible living unrelated kidney transplantation

A 59-yr-old Japanese woman with chronic renal failure caused by IgA nephropathy and antineutrophil cytoplasmic antibody (ANCA)-related glomerulonephritis underwent kidney transplantation from a living unrelated spousal donor. The blood type was compatible, while the human leukocyte antigen (HLA) typing showed a 5/6 locus mismatch. She had become pregnant twice by her donor and had never received blood transfusions. Complement-dependent cytotoxicity cross-match, flow cytometry cross-match (FCXM), and flow panel reactive antibody (PRA) were negative. She initially underwent one week of immunosuppression with mycophenolate mofetil (MMF) and double filtration plasmapheresis (DFPP) immediately before transplantation to reduce the risk of antibody-mediated rejection. Induction therapy consisted of MMF, tacrolimus (TAC), methylprednisolone (MP), and basiliximab. The allograft function was excellent immediately after the operation. However, the urine output and platelet count declined rapidly on post-operative day (POD) 3, while the serum creatinine (sCr) and lactate dehydrogenase levels rose gradually. Subsequently, we could not detect the diastolic arterial flow on Doppler sonography. We diagnosed accelerated acute rejection and treated her with plasma exchange (PEX), intravenous MP pulse therapy, and rituximab. The first episode biopsy on POD 7 revealed acute vascular rejection and acute antibody-mediated rejection (Banff score AMR II). Her urinary excretion increased beginning on POD 13, while the sCr level decreased gradually and reached 0.9 mg/dL on POD 22. In our retrospective analysis, the LAB screen detected donor-specific antibody (DSA). This case suggested that, for successful kidney transplantation in highly sensitized recipients, such as husband-to-wife spousal kidney transplantation with a history of pregnancy, we should keep the risk of AMR in mind, even if the sensitive antibody detection tests are negative.

Significance of Reversal of Diastolic Blood Flow in the Evolution of Testicular Infarction as a Complication of Epididymo-Orchitis

We report a case of a 50-year-old male who presented to the Emergency Department and was diagnosed with epididymo-orchitis. Sonographic evaluation of the testicle initially showed a normal, low resistance color Doppler waveform. The patient was admitted to the hospital. A follow up sonogram two days later demonstrated reversal of diastolic arterial flow on Pulse-Wave color Doppler imaging. Reversal of diastolic blood flow in testicular color Doppler sonography is a sign of impending infarction. On hospital day 6, the patient had a follow up ultrasound which demonstrated infarction of the testicle. Pathology confirmed the diagnosis and the tissue culture grew E. coli and Candida Albicans. This case documents the rapid progression of epididymo-orchitis with a normal spectral waveform to testicular infarction with reversal of diastolic blood flow on color Doppler imaging as a sign of impending infarction.

Role of Spectral Doppler Sonography in the Evaluation of Partial Testicular Torsion

The purpose of this series was to evaluate the role of spectral Doppler and color flow Doppler sonography in the evaluation of partial testicular torsion. Eight cases of partial testicular torsion, diagnosed on the basis of abnormal spectral Doppler waveforms or abnormal color flow Doppler findings, were retrospectively pooled from 2 teaching hospitals. The age group ranged from 4 to 85 years. Testicles with partial testicular torsion showed variable spectral Doppler patterns, including increased, similar, or decreased amplitude of the arterial waveform relative to the contralateral testicle. Two cases showed reversal of arterial diastolic flow, and 1 case showed diastolic flow variability within the same testicle. Decreased blood flow was observed on color flow Doppler sonography in 7 of the 8 patients. Variability of the Doppler waveform when compared with the contralateral testicle and reversal of diastolic blood flow are indirect clues that aid in the diagnosis of partial testicular torsion.

Focal ischemic necrosis in advanced biliary atresia cirrhosis

This report correlates the clinical and biological findings, liver hemodynamics and histological features of focal INL in an infant with BA cirrhosis. An eight month old boy with BA, with previous successful porto-enterostomy, was admitted with signs of cholangitis and ascites. He was treated with antibiotics and diuretics with subsequent clinical improvement. Eight days later, while being fed with hyper-osmolar milk, he became febrile again: ASAT/ALAT climbed (9000/2300 IU/L), liver function deteriorated. Infectious work-up was negative. Liver-ultrasound showed reversed portal flow and a negative arterial diastolic flow. The patient recovered within five days under supportive treatment. A similar event recurred five days later. INL was suspected and semi-urgent living-related liver transplantation was performed, with uneventful post-operative course. Histology of the explanted liver showed extensive foci of INL of different ages. This report illustrates how the association of reversed portal and arterial diastolic flows, with subsequent liver hypoperfusion, may repeatedly cause foci of INL in BA cirrhosis, and lead to rapid progression to liver failure. Because of precarious hepatic blood supply in such patients, close monitoring of portal and diastolic arterial flows is recommended.

“Splenic artery steal syndrome” is a misnomer: The cause is portal hyperperfusion, not arterial siphon

Splenic artery embolization (SAE) improves hepatic artery (HA) flow in liver transplant (OLT) recipients with so-called splenic artery steal syndrome. We propose that SAE actually improves HA flow by reducing the HA buffer response (HABR). Patient 1: On postoperative day (POD) 1, Doppler ultrasonography (US) showed patent vasculature with HA resistive index (RI) of 0.8. On POD 4, aminotransferases rose dramatically; his RI was 1.0 with no diastolic flow. Octreotide was begun, but on POD 5 US showed reverse diastolic HA flow with no signal in distal HA branches. After SAE, US showed markedly improved flow, RI was 0.6, diastolic flow in the main artery, and complete visualization of all distal branches. By POD 6, liver function had normalized. RI in the main HA is 0.76 at 2 months postsurgery. Patient 2: On POD 1, RI was 1.0. US showed worsening intrahepatic signal, with no signal in the intrahepatic branches and reversed diastolic flow despite good graft function. On POD 7, SAE improved the intrahepatic waveform and RI (from 1.0 to 0.72). Patient 3: Intraoperative reverse diastolic arterial flow persisted on PODs 1, 2, and 3, with progressive loss of US signal in peripheral HA branches. SAE on POD 4 improved the RI (0.86) and peripheral arterial branch signals. Patient 4: US on POD 1 showed good HA flow with a normal RI (0.7). A sudden waveform change on POD 2 with increasing RI (0.83) prompted SAE, after which the wave form normalized, with reconstitution of a normal diastolic flow (RI 0.68). In conclusion, these reports confirm the usefulness of SAE for poor HA flow but suggest that inflow steal was not the problem. Rather than producing an increase in arterial inflow, SAE worked by reducing portal flow and HABR, thereby reducing end-organ outflow resistance. Evidence of this effect is the marked reduction of the RI after the SAE to 0.6, 0.72, 0.86, and 0.68, in patients 1-4, respectively. SAE reduces excessive portal vein flow and thereby ameliorates an overactive HABR that can cause graft dysfunction and ultimately HA thrombosis.

Developmental Changes in Ovine Myocardial Glucose Transporters and Insulin Signaling Following Hyperthermia-Induced Intrauterine Fetal Growth Restriction

Developmental changes in ovine myocardial glucose transporters and insulin signaling following hyperthermia-induced intrauterine fetal growth restriction (IUGR) were the focus of our study. Our objective was to test the hypothesis that the fetal ovine myocardium adapts during an IUGR gestation by increasing glucose transporter protein expression, plasma membrane-bound glucose transporter protein concentrations, and insulin signal transduction protein concentrations. Growth measurements and whole heart tissue were obtained at 55 days gestational age (dGA), 90 dGA, and 135 dGA (term = 145 dGA) in fetuses from control (C) and hyperthermic (HT) pregnant sheep. Additionally, in 135 dGA animals, arterial blood was obtained and Doppler ultrasound was used to determine umbilical artery systolic (S) and diastolic (D) flow velocity waveform profiles to calculate pulsatility (S - D/mean) and resistance (S - D/S) indices. Myocardial Glut-1, Glut-4, insulin signal transduction proteins involved in Glut-4 translocation, and glycogen content were measured. Compared to age-matched controls, HT 90-dGA fetal body weights and HT 135-dGA fetal weights and gross heart weights were lower. Heart weights as a percent of body weights were similar between C and HT sheep at 135 dGA. HT 135-dGA animals had (i) lower fetal arterial plasma glucose and insulin concentrations, (ii) lower arterial blood oxygen content and higher plasma lactate concentrations, (iii) higher myocardial Glut-4 plasma membrane (PM) protein and insulin receptor beta protein (IRbeta ) concentrations, (iv) higher myocardial glycogen content, and (v) higher umbilical artery Doppler pulsatility and resistance indices. The HT ovine fetal myocardium adapts to reduced circulating glucose and insulin concentrations by increasing plasma membrane Glut-4 and IRbeta protein concentrations. The increased myocardial Glut-4 PM and IRbeta protein concentrations likely contribute to or increase the intracellular delivery of glucose and, together with the increased lactate concentrations, enhance glycogen synthesis, which allows for maintained myocardial growth commensurate with fetal body growth.

Neonates with hypoplastic left heart syndrome have ultrasound evidence of abnormal superior mesenteric artery perfusion before and after modified Norwood procedure

To a) describe superior mesenteric artery resistive index, as an estimate of perfusion, before and after modified Norwood; and b) assess incidence of diastolic flow reversal in the superior mesenteric artery before and after modified Norwood. Prospective observational trial. Children's hospital pediatric intensive care unit. Ten newborns with hypoplastic left heart syndrome. Ultrasound documentation of superior mesenteric artery diastolic flow direction and measurement of superior mesenteric artery resistive index 24-48 hrs before and 24-48 hrs after modified Norwood. Seven males and three females were enrolled. There was no change between the superior mesenteric artery resistive index pre- vs. postoperatively-0.99 (95% confidence interval, 0.85, 1.12) vs. 1.07 (95% confidence interval, 1.0, 1.15) (p = .13). Incidence of retrograde diastolic blood flow in the superior mesenteric artery was not different pre- vs. postoperatively (70% vs. 50%, p = .41). No patients developed necrotizing enterocolitis and all survived to hospital discharge. Ultrasound measurements in neonates with hypoplastic left heart syndrome suggest that superior mesenteric artery perfusion, as measured by resistive index, is impaired. Superior mesenteric artery diastolic flow reversal is common before and immediately after modified Norwood.