Unanticipated admissions to paediatric cardiac critical care after cardiac catheterisations.

OBJECTIVES: Cardiac catheterisation is commonly used for diagnosis and therapeutic interventions in paediatric cardiology. The inherent risk of the procedure can result in unanticipated admissions to critical care. Our goals were to provide a qualitative description of characteristics and evaluation of children admitted unexpectedly to the cardiac critical care unit (CCCU). METHODS: A retrospective single centre review of cardiac catheterisation procedures was done between 1 January, 2003 and 30 April, 2013. RESULTS: Of 9336 cardiac catheterisations performed, 146 (1.6%) were admitted from the catheterisation laboratory to the CCCU and met inclusion criteria. Of these 146 patients, 117 (1.3%) met criteria for unexpected admission and 29 (0.3%) were planned admissions. The majority admitted unexpectedly were below 1 year of age without co-morbidity aside from heart disease. Patients with planned admissions were significantly more likely to have single ventricle physiology, undergoing angiography or transferred for observation. Most unplanned admissions were triggered by interventional catheterisations or procedure-related complications. Patients received mechanical ventilation as the main CCCU management. Eighteen patients needed either cardiopulmonary resuscitation and/or extracorporeal membrane oxygenation during their catheterisation. About 106/117 (90.6%) patients survived to hospital discharge with no deaths in the planned admission group. CONCLUSIONS: Admission to CCCU following cardiac catheterisation was uncommon and tended to occur in younger children undergoing interventional procedures. Outcomes did not differ between patients experiencing planned and unplanned CCCU admission. Ongoing development of risk stratification tools may help to decrease unplanned CCCU admissions. Further studies are needed to determine whether unplanned admission following paediatric cardiac catheterisation should be utilised as a quality indicator

Regional ventricular wall motion abnormalities in tricuspid atresia after the fontan procedure

AbstractObjectieves. The purpose of this study was to determine whether wall motion abnormalities are present before or after the Fontan procedure in patients with a univentricular heart of the left ventricular type with an absent right atrioventricular valve connection (tricuspid atresia) and to assess the impact of such abnormalities on ventricular performance and clinical outcome.Background. Normal systolic and diastolic ventricular (unction is critical for a successful Fontan repair. However, there have been no previous studies addressing the relation between regional ventricular function and hemodynamic factors.Methods. Thirty-seven pediatric patients were studied with biplane ventricular cineangiography. There were 20 male and 17 female patients whose mean age at the time of the Fontan operation was 6.5 ± 3.5 years (range 2.5 to 15.6). Eighteen patients were studied preoperatively, 25 at >1 year postoperatively and 6 serially. Wall motion was assessed by a centerline method. Normal ranges for wall motion and other variables were established from 25 normal subjects.Results. Wall motion abnormalities were observed in 2 of 18 patients preoperatively and in 11 of 25 patients postoperatively. Age at operation and ventricular volumes did not differ between postoperative patients who had normal (group I, 14 patients) or abnormal (group II, 11 patients) wall motion. However, ventricular mass and the mass/volume ratio were significantly greater and systolic variables and cardiac index were significantly lower in group II versus group I. Two patients in group I were considered to have a clinically poor outcome (persistent heart failure), and five in group II had heart failure, including one who died late.Conclusions. These observations suggest that postoperative regional wall motion abnormalities in this setting are not rare, may be related to excessive hypertrophy and may contribute to cardiac dysfunction and a poor clinical outcome

Use of 3D rotational angiography to perform computational fluid dynamics and virtual interventions in aortic coarctation

Computational fluid dynamics (CFD) can be used to analyze blood flow and to predict hemodynamic outcomes after interventions for coarctation of the aorta and other cardiovascular diseases. We report the first use of cardiac 3‐dimensional rotational angiography for CFD and show not only feasibility but also validation of its hemodynamic computations with catheter‐based measurements in three patients.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154333/1/ccd28507.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154333/2/ccd28507_am.pd

Balloon angioplasty of native coarctation: clinical outcomes and predictors of success

AbstractOBJECTIVESWe sought to investigate the clinical impact of balloon angioplasty for native coarctation of the aorta (CoA) and determine predictors of outcome.BACKGROUNDBalloon dilation of native CoA remains controversial and more information on its long-term impact is required.METHODSHemodynamic, angiographic and follow-up data on 69 children who underwent balloon angioplasty of native CoA between 1988 and 1996 were reviewed. Stretch, recoil and gain of CoA circumference and area were calculated and related to outcomes.RESULTSInitial systolic gradients (mean ± SD, 31 ± 12 mm Hg) fell by −74 ± 27% (p < 0.001), with an increase in mean CoA diameters of 128 ± 128% in the left anterior oblique and 124 ± 87% in the lateral views (p < 0.001). Two deaths occurred, one at the time of the procedure and one 23 months later, both as a result of an associated cardiomyopathy. Seven patients had residual gradients of >20 mm Hg. One patient developed an aneurysm, stable in follow-up, and four patients had mild dilation at the site of the angioplasty. Freedom from reintervention was 90% at one year and 87% at five years with follow-up ranging to 8.5 years. Factors significantly associated with decreased time to reintervention included: a higher gradient before dilation, a smaller percentage change in gradient after dilation, a small transverse arch and a greater stretch and gain, but not recoil.CONCLUSIONBalloon dilation is a safe and efficient treatment of native CoA in children. Greater stretch and gain are factors significantly associated with reintervention, possibly related to altered elastic properties and vessel scarring

Delayed onset of tricuspid valve flow in repaired tetralogy of Fallot: an additional mechanism of diastolic dysfunction and interventricular dyssynchrony

<p>Abstract</p> <p>Background</p> <p>Diastolic dysfunction of the right ventricle (RV) is common after repair of tetralogy of Fallot. While restrictive physiology in late diastole has been well known, dysfunction in early diastole has not been described. The present study sought to assess the prevalence and mechanism of early diastolic dysfunction of the RV defined as delayed onset of the tricuspid valve (TV) flow after TOF repair.</p> <p>Methods</p> <p>The study population consisted of 31 children with repaired TOF (mean age ± SD, 12.3 ± 4.1 years) who underwent postoperative cardiovascular magnetic resonance (CMR). The CMR protocol included simultaneous phase-contrast velocity mapping of the atrioventricular valves, which enabled direct comparison of the timing and patterns of tricuspid (TV) and mitral (MV) valve flow. The TV flow was defined to have delayed onset when its onset was > 20 ms later than the onset of the MV flow. The TV and MV flow from 14 normal children was used for comparison. The CMR results were correlated with the findings on echocardiography and electrocardiography.</p> <p>Result</p> <p>Delayed onset of the TV flow was observed in 16/31 patients and in none of the controls. The mean delay time was 64.81 ± 27.07 ms (8.7 ± 3.2% of R-R interval). The delay time correlated with the differences in duration of the TV and MV flow (55.94 ± 32.88 ms) (r = 0.90, <it>p </it>< 0.001). Delayed onset was associated with prolongation of the RV ejection time in 9 and delayed onset and cessation of the pulmonary arterial flow in 4. Delayed onset was not associated with timing changes in the pulmonary artery in 3. The patients with delayed onset showed reduced RV ejection fraction (p = 0.01). However, the two groups did not show significant differences in TV E/A ratio, ventricular end-diastolic volumes, left ventricular ejection fraction, pulmonary regurgitant fraction, heart rate, PR interval and QRS duration.</p> <p>Conclusions</p> <p>Early diastolic dysfunction with delayed onset of TV flow is common after TOF repair, and is associated with reduced RV ejection fraction. It is a further manifestation of interventricular dyssynchrony and represent an additional mechanism of ventricular diastolic dysfunction.</p

Perturbation theory for the one-dimensional trapping reaction

We consider the survival probability of a particle in the presence of a finite number of diffusing traps in one dimension. Since the general solution for this quantity is not known when the number of traps is greater than two, we devise a perturbation series expansion in the diffusion constant of the particle. We calculate the persistence exponent associated with the particle's survival probability to second order and find that it is characterised by the asymmetry in the number of traps initially positioned on each side of the particle.Comment: 18 pages, no figures. Uses IOP Latex clas

A Wide Field Survey of Satellite Galaxies around the Spiral Galaxy M106

We present a wide field survey of satellite galaxies in M106 (NGC 4258) covering a 1.7\degr \times 2\degr field around M106 using Canada-France-Hawaii Telescope/MegaCam. We find 16 satellite galaxy candidates of M106. Eight of these galaxies are found to be dwarf galaxies that are much smaller and fainter than the remaining galaxies. Four of these galaxies are new findings. Surface brightness profiles of 15 out of 16 satellite galaxies can be represented well by an exponential disk profile with varying scale length. We derive the surface number density distribution of these satellite galaxies. The central number density profile (d $<100$ kpc) is well fitted by a power-law with a power index of $-2.1\pm0.5$, similar to the expected power index of isothermal distribution. The luminosity function of these satellites is represented well by the Schechter function with a faint end slope of $-1.19^{+0.03}_{-0.06}$. Integrated photometric properties (total luminosity, total colour, and disk scale length) and the spatial distribution of these satellite galaxies are found to be roughly similar to those of the Milky Way and M31.Comment: Accepted by MNRA

Laser treatment in diabetic retinopathy

Diabetic retinopathy is a leading cause of visual impairment and blindness in developed countries due to macular edema and proliferative diabetic retinopathy (PDR). For both complications laser treatment may offer proven therapy: the Diabetic Retinopathy Study demonstrated that panretinal scatter photocoagulation reduces the risk of severe visual loss by >= 50% in eyes with high-risk characteristics. Pan-retinal scatter coagulation may also be beneficial in other PDR and severe nonproliferative diabetic retinopathy (NPDR) under certain conditions. For clinically significant macular edema the Early Treatment of Diabetic Retinopathy Study could show that immediate focal laser photocoagulation reduces the risk of moderate visual loss by at least 50%. When and how to perform laser treatment is described in detail, offering a proven treatment for many problems associated with diabetic retinopathy based on a high evidence level. Copyright (c) 2007 S. Karger AG, Basel

Localizing gravity on a 't Hooft-Polyakov monopole in seven dimensions

We present regular solutions for a brane world scenario in the form of a 't Hooft-Polyakov monopole living in the three-dimensional spherical symmetric transverse space of a seven-dimensional spacetime. In contrast to the cases of a domain-wall in five dimensions and a string in six dimensions, there exist gravity-localizing solutions for both signs of the bulk cosmological constant. A detailed discussion of the parameter space that leads to localization of gravity is given. A point-like monopole limit is discussed.Comment: 29 pages, 17 figure