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Abnormalities in microvasculature and neovascular formation in the process of cardiac remodeling, and the relationship between angiogenesis and cardiac remodeling have not been elucidated, in dilated cardiomyopathy (DCM) and heart failure. To clarify the alterations in capillary microvasculature and the role of angiogenesis in cardiac remodeling, we examined the myocyte density, fibrous tissue volume, expression of genes relating to fibrosis, capillary density, and the expression of the genes for vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) at the ages of 5, 13, and 20 weeks and also investigated the effects of long-term treatment with amlodipine, nifedipine, and MCI-154 on capillary microvasculature and cardiac angiogenesis in hearts of the TO2 strain of cardiomyopathic hamster. Cardiomyopathic hamsters showed decreases in capillary density and proportion of venular capillaries concomitantly with a decrease in numerical myocyte density and enhanced expression of the genes for collagen I, collagen III, and transforming growth factor-β1, (TGF-β1,) leading to cardiac fibrosis. Long-term treatment with amlodipine and MCI-154 suppressed decreases in capillary density and the proportion of venular capillaries concomitantly with induction of VEGF and bFGE In conclusion, alterations in capillary microvasculature may be involved in the process of cardiac remodeling during dilated cardiomyopathy. Suppression of angiogenesis may be related to alterations in capillary microvasculature. Induction of cardiac angiogenesis may be a new strategy for the treatment of the remodeling process in dilated cardiomyopathy.

This paper describes a three-dimensional (3D) dynamic heart imaging system. In this system, ultrasound B-mode images are measured with a transesophageal probe, a 3D heart image at a given phase of the cardiac cycle is reconstructed with a volume rendering technique and image processing and a 3D dynamic heart image is presented by displaying the 3D static images sequentially in the cardiac cycle. Furthermore, a 3D heart image is divided into two regions with a section, and a B-mode image is reconstructed and superimposed on that section. Experimental results indicate that the system enables us not only to observe the motion of the myocardium, the mitral valve and so on from any point of view but also to observe the inside structure of the heart in detail using the 3D image and the reconstructed B-mode image.

Mechanisms for the development of functional tricuspid regurgitation (TR) were studied in 41 patients by ultrasound. The severity of TR was classified into 4 grades according to the extent of the regurgitant signal by pulsed Doppler echocardiography (echo). No TR signal was detected in 11 patients; the grade of TR was 1+ in 9 patients, 2+ in 10, 3+ in 8 and 4+ in 9. Using 2-dimensional echo, the tricuspid anular area was estimated from a horizontal and a sagittal diameter of the anulus, and systolic configurations of the tricuspid valve was observed. The tricuspid anular area corrected for body surface area increased with the grade of TR. Anterior displacement of the tips of the tricuspid leaflets was seen in 10 patients with TR of 2+ or greater severity, and its frequency also increased with the grade of TR. Loss of coaptation was seen in 3 patients with 4+ TR and malaligned coaptation was seen in 4 patients with TR of variable degrees. Tricuspid anular dilatation and anterior displacement of the tricuspid leaflet tips causes a separation between the leaflet tips and appears to be the main mechanisms for the development of functional TR. Malaligned coaptation also plays a role in the development of functional TR.

Mitral valve prolapse is diagnosed in real-time two-dimensional echocardiograms when there are discrepancies in the coaptation zone of the anterior mitral leaflet and the posterior mitral leaflet. Out of the 100 cases of mitral valve prolapse diagnosed in this way, 65 had prolapsed anterior mitral leaflets, 28 prolapsed posterior mitral leaflets and 7 prolapses of both the anterior and posterior mitral leaflets. In addition to the cases with mitral valve prolapse 23 cases of ruptured chordae tendineae of the mitral valve, including 15 cases which had undergone surgery, were investigated. The frequent site of mitral valve prolapse was the posteromedial commissure in the anterior leaflet and the posteromedial and anterolateral commissures in the posterior leaflet. These sites coincide with those where rupture of the chordae tendineae of the mitral valve was apt to occur. An investigation of the relation between age and mitral valve prolapse showed that the number of cases of prolapsed anterior leaflet did not increase with age, but there was an age-related increase in the number of cases of prolapsed posterior leaflets. It was also found that the degree of the prolapse progressed with age. Many of the cases of ruptured chordae tendineae of the mitral valve were in their forties or fifties, and there appeared to be some relation between the progress of the prolapse and age. Mitral regurgitant murmurs were recorded on phonocardiograms, and the severer the degree, the wider the range of the prolapse. Mitral regurgitation was more likely to occur in cases of prolapsed posterior leaflets than in those with prolapsed anterior leaflets, even if the degree and the range of the prolapse were mild.

Panicle size or 'sink' capacity of rice is determined by the number and size of spikelets. The variation of grain size is very small in Japanese cultivars, and the potential use of large grain genotypes for improving yield has not been studied extensively. In order to investigate the effect of a large grain gene, Lk-f, on various agronomic traits including yield potential, a total of 38 F7 isogenic pairs for the Lk-f locus were produced from F6 heterozygous plants (Lk-f/lk-f) of a cross 'Shin-2' × 'Fusayoshi'. These isogenic pairs were grown at Kurashiki (southern Japan) and Kuroishi (northern Japan). The duration of sunshine was almost similar in both location, but temperature was always ca. 5°C higher at Kurashiki throught the crop season (Fig. 1).

A large surplus portion of the mitral leaflets appears to be involved in the systolic anterior motion (SAM) of the mitral valve in hypertrophic cardiomyopathy (HCM). To understand the exact features and the mechanism of the surplus leaflet, we studies the mitral valve and its ring quantitatively with two-dimensional echocardiography in 17 patients with HCM (5 with large SAM, 6 with small SAM and 6 without SAM) and 10 normal subjects. In the large SAM group, the surplus length of the anterior mitral leaflet (AML) increased but that of the posterior mitral leaflet (PML) did not increase when compared to the other 3 groups. In the large SAM group, the length of AML was greater than in the normal group and the length of PML was greater than in the other 3 groups. The mid-systolic anteroposterior diameter of the mitral ring did not differ among the 4 groups. The mid-systolic position of the coaptation was more anterior in the large SAM group than in the other 3 groups. In conclusion, the surplus size of AML is actually increased in the patients with HCM and large SAM, which is caused by the elongation of both AML and PML with anteriorly displaced coaptation and with no dilation of the mitral ring.

本研究の目的は,臨床例における諸種の三尖弁形態変化と三尖弁閉鎖不全との対応について総合的に検討することである.対象154例について,断層心エコー図法を用いて三尖弁形態を観察し,また,パルスドプラ法にて三尖弁閉鎖不全の有無と1+から4+に至る重症度を判定した.先天性の弁形態異常は9例で,うちEbstein奇型や三尖弁異形成で3+以上の重症三尖弁閉鎖不全との関連が深かつた.残る145例については,三尖弁輪の大きさ,弁器質的変化,弁輪線を基準とした収縮期の弁位置ならびに弁尖接合形態などを分析した.弁輪拡大の程度は三尖弁閉鎖不全の重症度と良く対応した.三尖弁閉鎖不全の発生頻度は,弁器質的変化(15例),弁尖の6mm以上の前方偏位(17例)および弁尖接合の欠如(6例)で100%,また,不整弁尖接合(12例)で92%と高頻度であつた。3+以上の重症三尖弁閉鎖不全の発生頻度は,ドーム形成を伴う弁器質的変化(4例)と弁尖接合の欠如で100%, 6mm以上の前方偏位で88%と高かつた.一方,弁後方偏位は, 3mm以上(44例)ないし6mm以上(16例)のいずれで定義しても三尖弁閉鎖不全の有無,重症度との関連が希薄であつた.これらは,三尖弁閉鎖不全の発生と進展の機序を解明する上で,また,臨床上,断層心エコー図法にこて三尖弁閉鎖不全を検索する上で示唆に富む成績と考える.

Describes a three-dimensional (3D) reconstruction and presentation technique to visualize myocardial motion and blood flow using 1 cine-magnetic resonance (MR) image. First, myocardium and blood were extracted on a cine-MR image with certain threshold gray values. Second, with successive two slices of cine-MR image, some slices were interpolated and inserted in the two slices to reconstruct a 3D image. Final, a dynamic image was presented with displaying 3D images sequentially. The 3D dynamic image shows anatomical information such as myocardium and functional information such as blood flow. Furthermore, this method enables to visualize not only normal but also abnormal blood flow in cine-mode.

目的:超音波パルスドプラー法(以下PDE)を用い,当科全身性エリテマトーデス(以下SLE)患者を対象に肺高血圧症(PH)の検索を行い,臨床検査所見について比較検討した.方法:超音波断層法とPDEの複合システムを用い,右室流出路又は肺動脈弁口部での血流速度パターンを表示しPH patternを検討した.結果: SLE 42例中7例にPH patternが認められ,この群ではRaynaud現象,抗RNP抗体,血小板減少が高頻度に認められた.