To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
We encountered a paediatric case of graft failure due to antibody-mediated rejection after heart transplantation in which ivabradine was effective. Inappropriate sinus tachycardia in denervated transplanted hearts is a good indication for ivabradine administration as beta-blockers have a limited efficacy. To our knowledge, this is the first report on the effectiveness of ivabradine in a paediatric heart transplant rejection case.
A baby with complete atrioventricular block was born with a birth weight of 1403 g. Isoproterenol was ineffective and emergency pacing was required. Since transcutaneous pacing was ineffective and transvenous pacing was untenable due to small body size, transesophageal pacing was performed for 3.5 hours until permanent pacemaker implantation. There were no complications. This is the first report of continuous transesophageal pacing in a very-low-birth-weight infant.
Liver fibrosis and cirrhosis are one of the critical complications in Fontan patients. However, there are no well-established non-invasive and quantitative techniques for evaluating liver abnormalities in Fontan patients. Intravoxel incoherent motion diffusion-weighted imaging with MRI is a non-invasive and quantitative method to evaluate capillary network perfusion and molecular diffusion. The objective of this study is to assess the feasibility of intravoxel incoherent motion imaging in evaluating liver abnormalities in Fontan children.
Materials and Methods:
Five consecutive Fontan patients and four age-matched healthy volunteers were included. Fontan patients were 12.8 ± 1.5 years old at the time of MRI scan. Intravoxel incoherent motion imaging parameters (D, D*, and f values) within the right hepatic lobe were compared. Laboratory test, ultrasonography, and cardiac MRI were also conducted in the Fontan patients. Results of cardiac catheterization conducted within one year of the intravoxel incoherent motion imaging were also examined.
In Fontan patients, laboratory test and liver ultrasonography showed almost normal liver condition. Cardiac catheter and MRI showed good Fontan circulation. Cardiac index was 2.61 ± 0.23 L/min/m2. Intravoxel incoherent motion imaging parameters D, D*, and f values were lower in Fontan patients compared with controls (D: 1.1 ± 0.0 versus 1.3 ± 0.2 × 10−3 mm2/second (p = 0.04), D*: 30.8 ± 24.8 versus 113.2 ± 25.6 × 10−3 mm2/second (p < 0.01), and f: 13.2 ± 3.1 versus 22.4 ± 2.4% (p < 0.01), respectively).
Intravoxel incoherent motion imaging is feasible for evaluating liver abnormalities in children with Fontan circulation.
We aimed to elucidate the relationship between severity of secondary mitral regurgitation and mitral valve geometry in children with dilated cardiomyopathy. The medical records of 16 children with dilated cardiomyopathy (median age, 1.2 years; range, 0.4–12.3 years) were reviewed. Mitral valve geometry was evaluated by measuring coaptation depth using echocardiographic apical four-chamber views at the initial presentation. Patients were dichotomised according to the mitral regurgitation severity: patients with moderate or severe secondary mitral regurgitation (n=6) and those with mild secondary mitral regurgitation (n=10). A total of 58 healthy children were considered as normal controls, and a regression equation to predict coaptation depth by body surface area was derived: coaptation depth [mm]=4.37+1.34×ln (body surface area [m2]) (residual standard error, 0.49; adjusted R2, 0.68; p<0.0001). Compared with patients with mild secondary mitral regurgitation, those with moderate or severe secondary mitral regurgitation had significantly larger coaptation depth z-scores (6.4±2.3 versus 1.9±1.4, p<0.005), larger mitral annulus diameter z-scores (3.6±2.6 versus 0.9±1.8, p<0.05), higher left ventricular sphericity index (0.89±0.07 versus 0.79±0.06, p<0.005), and greater left ventricular fraction shortening (0.15±0.05 versus 0.09±0.05, p<0.05). In conclusion, geometric alteration in the mitral valve and the left ventricle is associated with the severity of secondary mitral regurgitation in paediatric dilated cardiomyopathy, which would provide a theoretical background to surgical intervention for secondary mitral regurgitation in paediatric populations.
Systemic right ventricular systolic dysfunction is common late after atrial switch surgery for transposition of the great arteries. Total isovolumic time is the time that the ventricle is neither ejecting nor filling and is calculated without relying on geometric assumptions. We assessed resting total isovolumic time in this population and its relationship to exercise capacity.
A total of 40 adult patients with transposition of the great arteries after atrial switch – and 10 healthy controls – underwent transthoracic echocardiography and cardiopulmonary exercise testing from January, 2006 to January, 2009. Resting total isovolumic time was measured in seconds per minute: 60 minus total ejection time plus total filling time.
The mean age was 31.6 plus or minus 7.6 years, and 38.0% were men. There were 16 patients (40%) who had more than or equal to moderate systolic dysfunction of the right ventricle. Intra- and inter-observer agreement was good for total isovolumic time, which was significantly prolonged in patients compared with controls (12.0 plus or minus 3.9 seconds per minute versus 6.0 plus or minus 1.8 seconds per minute, p-value less than 0.001) and correlated significantly with peak oxygen consumption (r equals minus 0.63, p-value less than 0.001). The correlation strengthened (r equals minus 0.73, p-value less than 0.001) after excluding seven patients with exercise-induced cyanosis. No relationship was found between exercise capacity and right ventricular ejection fraction or long-axis amplitude.
Resting isovolumic time is prolonged after atrial switch for patients with transposition of the great arteries. It is highly reproducible and relates well to exercise capacity.
We sought to provide a new method for quantifying collateral aortopulmonary flow in patients subsequent to construction of a bidirectional cavopulmonary shunt, and to clarify the clinical advantages of the new method.
We performed lung perfusion scintigraphy and cardiac catheterization in 10 patients subsequent to construction of a bidirectional cavopulmonary shunt. First, the ratio of collateral to systemic flow was determined by whole-body images of lung perfusion scintigraphy, dividing the total lung count by the total body count minus the total lung count. Second, we integrated lung perfusion scintigraphy and cardiac catheterization data using a formula derived from the Fick principle, taking the ratio of pulmonary to systemic flow to be 1 plus the ratio calculated above and multiplied by the systemic saturation minus the inferior caval venous saturation divided by the pulmonary venous saturation minus the inferior caval venous saturation. Finally, the amount of collateral flow was obtained from the ratio of pulmonary to systemic flow. We evaluated the impact of collateral flow on the calculation of pulmonary vascular resistance.
The median age at bidirectional cavopulmonary shunt was 1.41 years, and the median age at catheterization was 2.33 years. The mean amount of collateral flow was 1.75 ± 0.46 litres/min/m2. The pulmonary vascular resistance calculated without considering the collateral flow was overestimated by an average of 57 ± 23%, compared to the resistance calculated with our new method.
The use of scintigraphy combined with catheterization allows accurate determination of aortopulmonary collateral flow, and avoids overestimation of pulmonary vascular resistance in these candidates for the Fontan circulation.
Email your librarian or administrator to recommend adding this to your organisation's collection.