Sheath placement in femoral artery during cardiac catheterization in children can influence pressure waveform.

INTRODUCTION: It is reported that pressure wave reflection is enhanced by external compression of the femoral artery. Therefore, it is possible that cardiac catheterization itself can influence the aortic pressure waveform. AIM: The purpose of this study is to clarify the influence of sheath placement in a femoral artery on the pressure waveform. METHODS: This study enrolled 21 pediatric patients (5.1±4.0years) who underwent cardiac catheterization. A sheath was placed in the femoral arteries of all patients. The change in the pressure waveform induced by the placement of the sheath was investigated using the b/a and d/a ratio of second derivative of a fingertip photoplethysmogram. A high b/a ratio means a stiff aorta and a low d/a ratio represents an enhancement of the aortic pressure wave reflection. RESULTS: By the placement of the sheath in their femoral arteries, the b/a ratio was not influenced (sheath (-): -0.556±0.081 vs. sheath (+): -0.558±0.072; p=0.896). However, the d/a ratio was significantly decreased (-0.150±0.074 vs. -0.185±0.084; p=0.0003). CONCLUSIONS: The placement of the femoral arterial sheath enhances the pressure wave reflection and would lead to a change in the central aortic pressure waveform.

B-type natriuretic peptide at the early stage of univentricular circulation reflects inadequate adaptation to volume overload.

BACKGROUND: Recent studies showed that children with univentricular heart have elevated plasma B-type natriuretic peptide (BNP) levels prior to bidirectional cavopulmonary anastomosis (BDCPA). However, it remains to be established whether BNP levels reflect the degree of hemodynamic overload and relate to long-term outcome in univentricular circulation. METHODS: Fifty one consecutive children with functionally univentricular heart prior to BDCPA were studied. All patients underwent cardiac catheterization and BNP measurement. Ventricular end-systolic wall stress (ESWS) and end-diastolic wall stress (EDWS) were calculated from cardiac catheterization data. RESULTS: Median age was 1.1 years and 34% were female. Median BNP concentration was 90.4 pg/ml. Patients with high BNP (≥ 100 pg/ml) had higher pulmonary to systemic flow ratio (p = 0.014), a greater end-diastolic volume (p=0.009), more severe atrioventricular valve regurgitation (p= 0.02) and lower ventricular mass to end-diastolic volume ratio (p=0.006). BNP levels strongly related to EDWS (r = 0.75, p< 0.0001) and ESWS (r = 0.63, p < 0.0001). During median follow-up period of 3.2 years, 15 patients died and one underwent heart transplantation for refractory heart failure. On multivariate Cox regression analysis, high BNP concentration was an independent predictor of death or transplantation (HR 3.05, CI: 1.06-8.83, p = 0.04). CONCLUSIONS: High BNP concentration at the first palliative stage towards Fontan circulation reflects high wall stress due to high volume load and insufficient ventricular hypertrophy. Moreover, high BNP levels at this stage were independently related to long-term outcome. BNP may be used as a guide to identify patients with high workload due to inadequate adaptation to hemodynamic load, who are at high risk.

Intracardiac Fontan procedure for heterotaxy syndrome with complex systemic and pulmonary venous anomalies.

OBJECTIVE: The extracardiac conduit procedure is widely used for patients with heterotaxy syndrome with complex systemic and pulmonary venous anomalies; however, it lacks conduit-growth potential and requires long-term anticoagulation. We present the intracardiac Fontan procedure, which eliminates the above-mentioned disadvantages. PATIENTS AND METHODS: Twenty-four patients (mean age, 4.1 years; weight, 13.0 kg) with heterotaxy syndrome underwent intracardiac Fontan operations between March 1995 and March 2008. In each patient, the anomalous systemic venous return with the isolated hepatic vein was redirected to the pulmonary artery using an intra-atrial baffle without obstructing the pulmonary venous pathway; this was accomplished by anterior (n=5), lateral (n=15) or posterior tunnel methods (n=4), depending on the anatomical relationship of the systemic and pulmonary venous pathways. RESULTS: There was one (4%) in-hospital and two (8%) late deaths in total. Five (21%) patients underwent re-operation for either pulmonary venous obstruction or supraventricular tachycardia. The actuarial 12-year survival was 86% (the Kaplan-Meier survival plot). The freedom from re-operation at 10 years was 77%. Anticoagulation was not required except for two patients (8%) who had prosthetic valves and coagulation disorder. Obstruction of the systemic venous pathway was not observed in any patient; however, five (20%) patients had clinically significant postoperative arrhythmias. At the final follow-up, all survivors were categorised as the New York Heart Association class I. CONCLUSIONS: Aided by detailed preoperative anatomical and physiological diagnoses, intracardiac Fontan procedures were technically feasible in patients with complex systemic and pulmonary venous anomalies. The specific cardiac anatomy in these patients warranted this procedure; however, taking into consideration the improved outcomes of the modified Fontan procedure, this method should be performed with deliberation.

Quantification of collateral aortopulmonary flow in patients subsequent to construction of bidirectional cavopulmonary shunts.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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/m(2). 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. CONCLUSIONS: 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.

Risk factor of interim failure and early detection of the high-risk patients with functional single ventricle after Blalock-Taussing shunt.

PURPOSE: The purpose of this study was to identify the risk factor of interim failure and to consider the method for detecting high-risk patients after Blalock-Taussing shunt. METHODS: Between 1990 and 2004, 64 patients with functional single ventricle and low pulmonary flow underwent Blalock-Taussing shunt. We evaluated risk factors of interim failure by Logistic regression. Furthermore, assessments by catheterization and echocardiography were compared between Group Completion (Group C; 36 patients who had completed the Fontan operation or were Fontan candidates) and Group Failure (Group F; 20 patients who died before the Fontan operation or dropped out from Fontan candidate). RESULTS: In Group C, the survival at 10 years was 93%. The risk factor of interim failure was a systemic ventricular end-diastolic volume (SVEDV) of more than 250% of normal after shunt. The ventricular volume by echocardiography in Group C had been maintained between 190% and 200% of normal. By contrast, the ventricle in Group F had been significantly dilated after postshunt short term. CONCLUSIONS: The risk factor of interim failure was postshunt ventricular dilation, and the dilation was identified after postshunt short term. We recommend volume study within two to three months after shunt, and bidirectional cavopulmonary anastomosis should be immediately indicated to patients with ventricular dilation.

Phenotypes with GATA4 or NKX2.5 mutations in familial atrial septal defect.

Recently, GATA4 and NKX2.5 were reported as the disease genes of atrial septal defect (ASD) but the relationship between the locations of their mutations and phenotypes is not clear. We analyzed GATA4 and NKX2.5 mutations in 16 familial ASD cases, including four probands with atrioventricular conduction disturbance (AV block) and two with pulmonary stenosis (PS), by PCR and direct sequencing, and examined their phenotypes clinically. Five mutations, including two GATA4 and three NKX2.5 mutations, were identified in 31.3% of the probands with ASD, and three of them were novel. The two GATA4 mutations in the probands without AV block were S52F and E359Xfs (c.1075delG) that was reported previously, and three NKX2.5 mutations in the probands with AV block were A88Xfs (c.262delG), R190C, and T178M. Additionally, we observed some remarkable phenotypes, i.e., dextrocardia with E359Xfs (c.1075delG) and cribriform type ASD with R190C, both of which are expected to be clues for further investigations. Furthermore, progressive, most severe AV block was closely related with a missense mutation in a homeodomain or with a nonsense/frame-shift mutation of NKX2.5 for which classification has not been clearly proposed. This pinpoints essential sites of NKX2.5 in the development of the conduction system.

CD40 ligand gene and Kawasaki disease.

Kawasaki disease (KD) is an acute systemic vasculitis syndrome of infants and young children. Although its etiology is largely unknown, epidemiological findings suggest that genetic factors play a role in the pathogenesis of KD. To identify genetic factors, affected sib-pair analysis has been performed. One of the identified peaks was located on the Xq26 region. A recent report of elevated expression of CD40 ligand (CD40L), which maps to Xq26, during the acute-phase KD, and its relationship to the development of coronary artery lesions (CAL) prompted us to screen for polymorphism of CD40L and to study the association of the gene to KD. A newly identified SNP in intron 4 (IVS4+121 A>G) is marginally over-represented in KD patients as compared to controls (109/602, 18.1 vs 111/737, 15.1%). When male KD patients with CAL were analyzed as a patient group, the SNP was significantly more frequent than in controls (15/58, 25.9%, vs 111/737, 15.1%, OR=2.0, 95% CI=1.07-3.66; P=0.030). Interestingly, this variation was extremely rare in a control Caucasian population (1/145, 0.7%). Our results suggest a role of CD40L in the pathogenesis of CAL and might explain the excess of males affected with KD.

Multiple fistulas from the coronary arteries to the left ventricle in tricuspid atresia.

It is rare to find multiple fistulas arising from all three coronary arteries and draining into the left ventricle. Coronary angiography revealed this anomaly in a one-year-old girl with tricuspid atresia after conversion to the Fontan circulation. To the best of our knowledge, this is the first report of such multiple fistulas in the setting of tricuspid atresia, and also the first report in childhood.

[Social concern and independence in adults with congenital heart disease].

OBJECTIVES: Recent advances in medical and surgical treatment have led to the survival of increasing numbers of adults with congenital heart disease (CHD). However, the social status of these patients remains unknown. This survey investigated the social prospects for adults with CHD, and the limiting factors for social independence. METHODS: A written questionnaire on patient characteristics, education, employability, marital status and insurability was designed to define the characteristics of social independence in adults with CHD. Randomly selected adults with CHD were enrolled: 13 patients with cyanotic unrepaired CHD (4 males, 9 females, mean age: 29.8 +/- 10 years, range: 18-56 years) and 102 patients with other CHDs (48 males, 54 females, mean age: 29.5 +/- 10 years, range: 18-74 years). RESULTS: University of California at Los Angeles functional class I-II was found in 94% of patients, medication in 46%, and hospitalization in 51%. Compared with the data from Japanese general population, study patients had a lower ratio of high school graduates (86% vs 94%), life insurability (51% vs 71%), marital status (31% vs 32%) and employability (82% vs 80%). Patients with unrepaired cyanotic CHD had significantly lower ratio than those with other CHDs (marital status 15%, p = 0.19; employability 40%, p = 0.0003; high school graduates 69%, p = 0.06; life insurability 18%, p = 0.02, respectively). CONCLUSIONS: Factors affecting social independence in adults with CHD were severity of disease, continuing medication, lower level of education, lower self-esteem, and unknown natural history of CHD. To improve social independence in these patients, further development of medical and surgical therapy and more detailed knowledge of the patients, caretakers and society in this field are needed.