Evaluation of right ventricular performance long after the atrial switch operation for transposition of the great arteries using the Doppler Tei index.

Right ventricular (RV) dysfunction may occur in patients after the atrial switch operation for d-transposition of the great arteries (d-TGA) and can be an important complication. Noninvasive assessment of RV function using echocardiography is necessary for following up these patients. We evaluated RV function using the Doppler Tei index (RV Tei index). The RV Tei index measures the ratio of total time intervals in isovolumetric contraction and relaxation to the ejection time. The subjects consisted of 33 patients who had undergone the atrial switch operation for d-TGA (the atrial switch group) (mean age, 21 +/- 4 years), 10 patients with pulmonary artery stenosis after the arterial switch operation for d-TGA (the arterial switch group) (mean age, 17 +/- 1 years), and 10 patients with a normally structured heart as a control group (mean age, 26 +/- 7 years). The RV Tei index (0.65 +/- 0.16) was significantly higher in the atrial switch group than in the arterial switch group (0.29 +/- 0.07) and the control group (0.29 +/- 0.01) (p < 0.05). The fractional area change of the RV obtained from the four-chamber view in the atrial switch group showed a significant negative correlation with the RV Tei index (r = -0.58, p < 0.01). The RV Tei index increased with increasing severity of the NYHA functional class. In the moderate/severe tricuspid regurgitation group, it was significantly higher than in patients with none/trivial tricuspid regurgitation. We conclude that the RV Tei index is useful for evaluating RV junction long after the atrial switch operation for d-TGA.

Confluent hepatic fibrosis in cirrhosis: ferumoxides-enhanced MR imaging findings.

We describe ferumoxides-enhanced magnetic resonance imaging findings in a 60-year-old man with confluent hepatic fibrosis in advanced cirrhosis. The extension and internal structure of confluent fibrosis were well demonstrated with ferumoxides-enhanced proton-density spin-echo magnetic resonance images, showing a wedge-shaped area of high signal intensity corresponding to the extension of fibrosis and internal focal areas of low signal intensity, presumably corresponding to residual functioning liver parenchyma. This case suggests a potential utility of ferumoxides-enhanced magnetic resonance imaging for characterizing this tumor-mimicking disorder.

Unrecognizable intramucosal spread of diffuse-type mucosal gastric carcinomas of less than 20 mm in size.

BACKGROUND: Diffuse-type intramucosal gastric carcinomas sometimes spread within the mucosa beyond their macroscopic margins, often causing positive resection margins upon local resections such as endoscopic mucosal resection. PATIENTS AND METHODS: A consecutive series of 34 patients with solitary, small (less than 20 mm in diameter macroscopically), and macroscopically well demarcated diffuse-type mucosal carcinomas, who were treated with gastrectomy followed by detailed pathological examination, were included in the present study. Unrecognizable intramucosal spread is defined as an area of cancer which is indistinguishable macroscopically from its peripheral noncancerous area, and covered by normal epithelium with neither morphologic nor color changes. We examined the extent of unrecognizable intramucosal spread, measuring the maximum distances between macroscopic and microscopic margins on the sections, and investigated its relationship with four factors: location of the lesion, macroscopic size, histologic ulcer formation, and degree of atrophy of the background mucosa. RESULTS: The maximum distance between macroscopic and microscopic margins was significantly larger (maximum 10 mm) in the background mucosas with marked atrophy than in those with little or no atrophy. No other factors, including location, macroscopic size and ulcer formation, correlated with it. CONCLUSION: We should pay particular attention to unrecognizable intramucosal spread, especially in markedly atrophied mucosa, when treating small diffuse-type mucosal gastric cancer by local resections such as endoscopic mucosal resection. In addition, because of unrecognizable intramucosal spread, a surgical incision margin of at least 10 mm from the macroscopic margin is indicated.

Long-term effect of angiotensin-converting enzyme inhibitor in volume overloaded heart during growth: a controlled pilot study.

OBJECTIVES: This study examined whether long-term therapy with an angiotensin-converting enzyme (ACE) inhibitor reduces excessive increases in left ventricular (LV) mass as well as volume in growing children with aortic regurgitation or mitral regurgitation. BACKGROUND: The ACE inhibitor reduces volume overload and LV hypertrophy in adults with aortic or mitral regurgitation. METHODS: This study included 24 patients whose ages ranged from 0.3 to 16 years at entry to the study. On echocardiography, we measured LV size, systolic function and mass. After obtaining baseline data, patients were allocated into two groups. Twelve patients were given an ACE inhibitor (ACE inhibitor group), and 12 patients were not (control group). Echo parameters were again assessed after an average 3.4 years of follow-up. RESULTS: Left ventricular parameters at baseline in the two groups were similar. The Z value of LV end-diastolic dimensions decreased from +0.82 +/- 0.55 to +0.57 +/- 0.58 in the ACE inhibitor group, whereas it increased from +0.73 +/- 0.85 to +1.14 +/- 1.04 in the control group (mean change -0.25 +/- 0.33 for the ACE inhibitor group vs. +0.42 +/- 0.48 for the control group, p = 0.0007). The mass normalized to growth also reduced from 221 +/- 93% to 149 +/- 44% of normal in the ACE inhibitor group and increased from 167 +/- 46% to 204 +/-59% of normal in the control group (mean change -72 +/- 89% of normal for the ACE inhibitor group vs. +37 +/- 35% of normal for the control group, p = 0.0007). CONCLUSIONS: Long-term treatment with ACE inhibitors is effective in reducing not only LV volume overload but also LV hypertrophy in the hearts of growing children with LV volume overload.

Genetic mapping of a locus associated with bovine chronic interstitial nephritis to chromosome 1.

Chronic interstitial nephritis with diffuse zonal fibrosis (CINF) occurs in Japanese Black cattle (Wagyu) as an autosomal recessive disorder leading to death prior to puberty, first six months or a year of life. We performed a genome-wide scan using microsatellite markers in a Wagyu pedigree segregating for CINF and mapped the CINF locus to bovine chromosome 1. CINF was closest to microsatellites BM9019 and INRA49 (Z score = 12.0; P < 3.4 x 10(-10)).

Clinical features of isolated noncompaction of the ventricular myocardium: long-term clinical course, hemodynamic properties, and genetic background.

OBJECTIVES: A nationwide survey was conducted to clarify the clinical features of isolated noncompaction of the ventricular myocardium (INVM) in Japanese children in comparison with features previously described in patients with INVM. BACKGROUND: Isolated noncompaction of the ventricular myocardium is a rare disorder characterized by an excessively prominent trabecular meshwork. It is accompanied by depressed ventricular function, systemic embolism and ventricular arrhythmia. METHODS: A questionnaire specifically designed for this study was sent to 150 hospitals in Japan where a pediatric cardiology division exists. RESULTS: Twenty-seven patients were diagnosed by two-dimensional echocardiography, their ages ranging from one week to 15 years at presentation, with follow-up lasting as long as 17 years. The gross anatomical appearance and the extension of noncompacted myocardium predominantly at the apex observed on two-dimensional echocardiograms were similar to observations reported previously. Dissimilarities included a greater number of asymptomatic patients at initial presentation, a longer clinical course with gradually depressed left ventricular function, no systemic embolism, and rare ventricular tachycardia in the Japanese children. Cardiac catheterization disclosed normal left ventricular end-diastolic volume and increased left ventricular end-diastolic pressure in most cases, consistent with restrictive hemodynamics. A higher incidence of Wolff-Parkinson-White syndrome was found in the children, whereas left bundle branch block was rarer than reported in adults. Familial recurrence was high (44%) and included many women. CONCLUSIONS: In Japanese children, INVM can be found by screening examinations at asymptomatic stage, and it might have a longer dinical course with gradually depressed left ventricular function and restrictive hemodynamics. The pattern of familial recurrence we observed implies that INVM is a distinctive clinical entity with a heterogeneous genetic background.

Intravascular ultrasound imaging before and after balloon angioplasty for pulmonary artery stenosis.

Previous reports regarding intravascular ultrasound (IVUS) imaging of the pulmonary arteries in children and its application to balloon pulmonary angioplasty are limited. This study was designed to compare findings of IVUS imaging and those of angiography of the pulmonary artery before and after the balloon angioplasty procedure. Thirty patients had significant pulmonary artery stenosis and underwent balloon angioplasty. In all, of 34 branch pulmonary arteries were dilated. All patients underwent both angiography and IVUS imaging at the time of balloon angioplasty. The mean age at balloon angioplasty was 5.7 +/- 4.0 yr. One echo-dense layer on IVUS was detected in 9% of the 34 stenotic vessels, and a two- or three-layered vascular wall pattern in 91%. The thickness of intima-medial layer (inner and middle layers) was greater than normal in 91% of stenotic vessels. After balloon angioplasty, intimal flaps and aneurysm were observed at 29 and 28 locations, respectively. Of these locations, the intimal flaps were detected by angiography in 44% and by IVUS in 100%; the aneurysm was detected by angiography in 61% and by IVUS in 93%. Media rupture was observed at 26 locations, and the change was detected only by IVUS. The present study suggests that intimal and medial changes in the pulmonary artery can be detected more precisely by IVUS than by angiography.

Atrial septal displacement for repair of anomalous pulmonary venous return into the right atrium.

BACKGROUND: In the repair of anomalous connection of the pulmonary veins to the right atrium, the use of a baffle of pericardium to divert the pulmonary venous blood into the left atrium could cause pulmonary venous obstruction as a result of thickening of the pericardial patch. Anomalous pulmonary venous drainage to the right atrium caused by malposition of the atrial septum primum can be repaired by displacing the shifted septum primum to the normal position. METHODS: In 5 patients with total (n=2) or partial (n=3) anomalous pulmonary venous drainage into the right atrium, the septum primum was shifted toward the left atrium and the pulmonary veins drained into the anatomic right atrium despite their normal connection with the posterior wall of the left atrium. This method consisted of incision of the posterior edge of the atrial septum primum and displacement of the incised atrial septum between the anomalous pulmonary veins and both venae cavae. No patch was used. RESULTS: Postoperative echocardiography showed a wide pathway from the pulmonary veins to the left atrium with no stenotic portions. No atrial arrhythmias occurred after the operation. CONCLUSIONS: This technique may be advantageous because it allows for future growth of the route of the pulmonary venous pathway and avoids postoperative supraventricular arrhythmias.

Clinical features and cardiopulmonary function of patients with atrophic heart in Duchenne muscular dystrophy.

The clinical features and cardiopulmonary function of 5 patients with atrophic heart in Duchenne muscular dystrophy (DMD) were studied by echocardiography and spirometry. Atrophic heart was defined as a state where the left ventricular end-diastolic volume decreased markedly during long-term follow-up (over 5 years). The patients with atrophic heart were more emaciated and showed more severe motor disability than the controls (18 DMD patients with a normal left ventricular cavity size). The pre-ejection period/ejection time ratio was significantly higher in patients with atrophic heart than in controls, and the maximal diastolic posterior wall velocity was reduced. The forced vital capacity was lower in patients with atrophic heart than in controls, but the one-second forced expiratory volume rate was similar in the 2 groups. Three patients with atrophic heart died. Examination at autopsy showed that their hearts were small and of low weight, and showed not only fibrosis, but also brown atrophy and waxy degeneration. These findings indicate that cardiopulmonary function is significantly reduced in DMD patients with atrophic heart.

[Mitral valve abnormalities in the hypoplastic right heart syndrome: echocardiographic observations].

Two-dimensional echocardiographic examinations were performed for 86 patients with the hypoplastic right heart syndrome (55 cases of tricuspid atresia, 9 of pure pulmonary stenosis and 22 of pure pulmonary atresia). Prolapse of the anterior mitral leaflet was detected in 14 patients (16.3%). Four of these 14 patients had mitral regurgitation. Among the patients with mitral valve prolapse, ruptured chordae tendineae of the mitral valve were detected in two, and elongation of the chordae in one. There were no significant relationships between the incidence of mitral valve prolapse and sex, age, type of tricuspid atresia, previous palliative surgery, or PaO2. However, one patient with pure pulmonary stenosis, who had had mitral valve prolapse without mitral regurgitation, developed mitral regurgitation several months after undergoing a Blalock-Taussig shunt operation. The mechanism responsible for mitral valve prolapse in the hypoplastic right heart syndrome is not clear. Multiple factors, such as long-standing left ventricular volume overload, hypoxic myocardial damage, and anatomical chordal abnormalities may cause mitral valve prolapse. The presence of a mitral valve abnormality has an important bearing on the natural history as well as the surgical procedure of choice. The need for careful echocardiographic examinations to detect mitral valve abnormalities in the hypoplastic right heart syndrome is thus underscored.

Change in pulmonary and systemic circulation in acute ventricular septal defect.

The correlation between left to right ventricular (L-R) shunt flow and other hemodynamic changes was studied in 16 dogs with an acute ventricular septal defect (VSD) and normal pulmonary vascular bed. The interventricular shunt flow was measured directly with a specially designed electromagnetic flowmeter probe, where the area of the VSD was constant. The sudden presentation of VSD increased pulmonary arterial pressure, pulmonary flow and left ventricular end-diastolic pressure. L-R shunt flow was not changed significantly by atrial pacing except when the rate was increased to over 200/min. Dogs with a VSD were treated with isoproterenol and dextran to vary the shunt flow and hemodynamic parameters. L-R shunt flow was decreased by isoproterenol and increased by dextran loading. The percentage changes of L-R shunt flow from pre-drug values correlated well with the change in left ventricular end-diastolic pressure (r = 0.75) and the ratio of pulmonary to systemic vascular resistance (r = -0.73). Change in total pulmonary vascular resistance had a greater effect on L-R shunt flow than did a change in systemic vascular resistance, whereas a change in aortic flow had less effect (r = 0.35) on L-R shunt flow than did a change in preload and afterload. The time to peak LV dP/dt, as an index of cardiac contractility, and heart rate were not correlated with the relative change in L-R shunt flow. These results indicate that L-R shunt flow induced by the sudden presentation of a VSD varied with changes in the pulmonary and systemic circulation.

Effects of interventricular shunt on indices of left ventricular function.

The accuracies of indices of left ventricle function were examined in an open-chest model in dogs with and without a ventricular septal defect, in which the ventricular shunt was opened and reclosed by a specially designed flowmeter probe with a cap. The systolic time interval, the maximal rate of pressure development in the left ventricle (+LV dP/dt), +LV dP/dt corrected for the isometric pressure (+LV dP/dt/Pd), and the time to +LV dP/dt (t-dP/dt) were determined by recording the aortic flow, ventricular shunt flow, aortic pressure, pulmonary arterial pressure, and left ventricular pressure. The isometric contraction time, the preejectional period, and the ejection time shortened with decrease of the mean aortic pressure and aortic flow, and the mean pulmonary arterial pressure increased after opening the ventricular shunt. When the pulse was varied by atrial pacing, the systolic time interval was affected in dogs both with and without a ventricular septal defect, but "isometric contraction time" was not affected in animals with a ventricular septal defect. Dopamine and methoxamine were used to evaluate the effects of the inotropic state and afterload on these indices. The extents of the changes in the systolic time interval and +LV dP/dt were different in animals with and without a ventricular septal defect, but the changes in preejectional period/ejection time, +LV dP/dt/Pd and t-dP/dt were similar in the two conditions. These results suggest that the systolic time interval and the indices of left ventricular pressure are useful in assessment of cardiac function only in certain conditions.