Tetsuro Kamiya

Plasma levels of adrenomedullin in primary and secondary pulmonary hypertension in patients <20 years of age

To elucidate the pathophysiologic significance of adrenomedullin in pulmonary hypertension, we measured plasma adrenomedullin-like immunoreactivity (AM-LI) concentrations in blood samples obtained from various sites during cardiac catheterization by using radioimmunoassay in patients with pulmonary hypertension in comparison with patients without pulmonary hypertension. In patients with pulmonary hypertension, plasma AM-LI concentrations were significantly elevated and there was a significant uptake of AM-LI in pulmonary circulation, indicating the involvement of adrenomedullin in the cardiovascular regulation of pulmonary circulation in pulmonary hypertension.

Left ventricular volume characteristics in children with tricuspid atresia before and after surgery

Abstract Left ventricular volume variables (left ventricular end-diastolic volume, ejection fraction, mass and systolic output) were quantified in (1) 13 patients with tricuspid atresia preoperatively (type Ia, 3 patients; type Ib, 9 patients; type IIb, 1 patient), (2) 4 patients after a shunt procedure (Blalock-Taussig, 3; Glenn, 1), and (3) 1 patient after corrective surgery. Cardiac catheterization and angiography were performed at age 1 month to 5.8 years (mean 1.4 years). All patients had decreased pulmonary blood flow. The results were compared with data in 15 patients with no significant heart disease. Left ventricular end-diastolic volume was significantly greater than normal in 12 of the 13 patients. Left ventricular mass was significantly greater than normal, but ejection fraction was significantly less than normal. There was a positive correlation between ejection fraction and systemic oxygen saturation. Left ventricular systolic index was normal in 9 of the 13 patients preoperatively. After a shunt procedure, left ventricular end-diastolic volume and systolic index increased significantly in all four patients, and ejection fraction improved greatly in three of the four. After corrective surgery, left ventricular end-diastolic volume and left ventricular systolic index returned to the normal range and left ventricular ejection fraction improved. These findings suggest that patients with tricuspid atresia have impaired left ventricular function.

CORONARY RISK FACTORS IN ACUTE KAWASAKI DISEASE : CORRELATION OF SERUM IMMUNOGLOBULIN LEVELS WITH CORONARY COMPLICATIONS

Abstract Background To determine the usefulness of the IgG z‐score (age and sex‐standardized serum IgG level) before intravenous gamma globulin therapy (1VGG) in predicting the occurrence or severity of coronary complications in Kawasaki disease (KD).

Elevated plasma levels of adrenomedullin in congenital cyanotic heart disease

Adrenomedullin is a novel hypotensive peptide originally isolated from human pheochromocytoma. Accumulating evidence suggests the possible involvement of adrenomedullin in the physiology of the pulmonary circulation and the pathophysiology of hypoxaemia. The aim of the present study was to investigate the pathophysiological significance of adrenomedullin in hypoxaemia caused by congenital cyanotic heart disease. Subjects were 16 patients with congenital cyanotic heart disease aged 0.8-10 years (Group C) and 12 age-matched control subjects (patients with coronary artery dilatation after Kawasaki disease; Group N). Plasma adrenomedullin concentrations were measured, using radioimmunoassay, in femoral venous, pulmonary arterial and pulmonary venous blood obtained during cardiac catheterization. Plasma adrenomedullin concentrations in Group C were significantly (3-fold) higher than those in Group N at all sampling sites. In Group C, plasma adrenomedullin concentrations in pulmonary venous blood were significantly lower than those in pulmonary arterial blood. Pulmonary uptake of adrenomedullin in Group C was significantly greater than that in Group N. Patients with congenital cyanotic heart disease showed elevated plasma adrenomedullin concentrations and an increased uptake of adrenomedullin in the pulmonary circulation, which may act to dilate pulmonary vessels and increase pulmonary blood flow to alleviate hypoxaemia. Intrinsically increased adrenomedullin levels may function as a compensatory mechanism for hypoxaemia in congenital cyanotic heart disease.

Follow-up Study of Coronary Arterial Lesion and Cardiac Performance in Kawasaki Disease

Kawasaki disease (DK) is an acute febrile illness affecting infants and children and may involve the coronary artery. Concerning the occurrence of the coronary arterial lesion (CAL), we reported the appearance of coronary aneurysm (AN) on two-dimensional echocardiography (2-D echo) early in the course of the disease. After the formation of AN, it had been reported that the size of AN might decrease in size or “regress” during the follow-up by angiocardiography or by 2-D echo. On the other hand, we had observed more than a few cases in which the stenotic lesion of the coronary artery (ST) developed in combination with AN during the follow-up. Concerning the effect of CAL on cardiac performance, we reported the decrease of left ventricular ejection fraction on angiocardiography in the cases with severe ST. The purpose of this study, based on the follow-up data of cardiac catheterization in cases with evidence of CAL on angiocardiography in our institute, is: 1) to clarify the incidence and time of occurrence of ST and the relationship between the quality of AN and ST, and 2) to analyze the effect of ST to cardiac performance and its time course, especially in cases with severe ST.

Noninvasive Evaluation of the Pulmonary Vascular Resistance by Pulsed Doppler Echocardiography

In congenital heart disease with left-to-right shunt, surgical indications and postoperative courses are critically influenced by associated pulmonary hypertension (PH). The purpose of this study is to evaluate the clinical validity of pulsed Doppler echocardiography (PDE) in assessing the reversibility of PH by surgical intervention in congenital heart disease associated with left-to-right shunt.

Treadmill Test in Children after Cardiac Surgery: Comparison to Cardiac Catheterization Data

There have been a number of reports on treadmill exercise (TM) testing for the postoperative evaluation of patients with congenital heart disease. However, the significance of the parameters observed during TM testing, in terms of their correlation with cardiac performance, has not been elucidated. The purpose of this study was to evaluate the validity of TM testing in assessment of the exercise capacity in postoperative patients, by comparing the findings of TM testing to the parameters of cardiac performance obtained by cardiac catheterization.

Rastelli operation as one stage anatomical correction for infants with complete transposition of the grat arteries and ventricular septal defect

We recently adopted the Rastelli operation as a one stage anatomical correction for three infants with transposition of the great arteries and associated with ventricular septal defect (TGA+VSD). In all, ventricular septal defect was enlarged by excision of the conus septum to avoid obstruction of intraventricular tunnel and Hancock valved conduits of 18 mm in diameter were used for reconstruction of pulmonary trunk. The postoperative function of the left ventricle proved to be better than that of the right ventricle, as the systemic ventricle, after the Mustard procedure for TGA+VSD. Our results show that the Rastelli operation is effective as a one stage anatomical correction in infants with TGA+VSD.