Purpose: Three-dimensional (3D) echocardiography is useful for the accurate evaluation of left ventricular (LV) function, but its reliability during exercise remains unclear. We conducted an investigation to determine whether 3D echocardiography was practicable for evaluating LV function during exercise. Subjects and Methods: We studied 18 healthy subjects (12 males, 6 females: 22.7±1.8 years). All subjects underwent supine bicycle ergometer exercise tests. We compared stroke volume index (SVI, stroke volume / body surface area), cardiac index (CI, cardiac output / body surface area), and LV ejection fraction (LVEF) during exercise using pulsed wave Doppler (PWD) and two-dimensional (2D) and 3D echocardiography. The inter-observer and intra-observer variations were measured repeatedly during exercise. Results: The SVI and CI measured by 3D echocardiography continued to increase during exercise, and these were accompanied by heart rate elevation. The inter-observer and intra-observer variations in LV volume measured by 3D echocardiography were better than those for PWD and 2D echocardiography. We could evaluate the dyssynchrony at maximum exercise using 3D echocardiography. Conclusion: 3D echocardiography is a reproducible tool that could feasibly be used for the evaluation of LV function during exercise.

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Widespread use of electronic medical records facilitates use of such secondary medical data as etiology and clinical trials. For secondary use, record categories and terminology must be standardized. We investigated textbooks being used in Japan to compile terms related to abdominal ultrasonography as well as terminology related to ultrasonography. Terminology assumes a hierarchical structure and resembles an ontology of concept-based relationships between terms and findings. Terminology also includes relationships between synonyms. In editing the terminology, we developed some tools that aid in the process of editing the terminology. The terminology browser, a branching browsing tool for hierarchical terminology, makes it easier to manage the terminology and can export Classification Markup Language (ClaML) files for standardized communication of terminology between information systems.

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Purpose: The accelerating effect on thrombolysis by combined use of 500-kHz low-frequency ultrasound (US), recombinant tissue plasminogen activator (rt-PA), and bubble liposomes (BLs) was verifi ed in vitro. Methods: A fibrin clot was formed by adding thrombin to bovine plasma. It was enclosed in a pressurized container, the pressure and temperature of which were maintained at 150 mmHg and 37°C, respectively. Ultrasonic conditions were set at a continuous wave, a frequency of 500kHz, an intensity of 0.7 W/ cm², and a sonication time of 60s. We derived the rate of reduction in clot weight from the decreased clot weight and the weight before sonication. We compared the rate of reduction in groups combining physiological saline, rt-PA, BLs, and US. Results: Only the rt-PA+US+BL group showed a signifi - cantly accelerated thrombolytic effect compared with any other group or with any combination of two factors in the 60-s period (0.001⟨P⟨0.027). Conclusion: BLs have great potential to accelerate the thrombolytic effect of rt-PA with low-frequency, 500-kHz, continuous-wave ultrasound.

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Coarctation of the aorta is a congenital disease accompanied by distal aortic arch stenosis at a part of ductus arteriosus joint. Two main types of coarctation of the aorta are that with and that without heart malformation including patent ductus arteriosus. Coarctation of the aorta is usually diagnosed by drug resistant hypertension or upper limb hypertension, usually appearing in adults. We encountered an adult case of coarctation of the aorta with vascular murmur on the back and hypertension. The patient was a 26-year-old-man who had visited a clinic complaining of a common cold. Physical examination had detected abnormal vascular sound on his back. When the patient came to this institution for further examination, his upper limb blood pressure was 132/70 mm Hg without laterality, and vascular murmur was audible on the left side of his back. Plain CT indicated dilatation of the thoracic aorta when it was compared to the abdominal aorta. Although we detected no abnormality or source of abnormal sound in the heart, the descending aorta was dilated (33 mm) and the transthracic echocardiogram showed internal mosaic signals. Moreover, mild hypoplasia of the aortic arch, coarctation in the descending aorta, and post stenotic dilatation in the distal part of the coarctation were observed when viewed in the suprasternal approach. Maximal velocity and presumed pressure gradient at the coarctation were 3.4 m/s and 46 mm Hg, respectively, determined using the continuous wave Doppler method. The abdominal aortic flow pattern was highly unusual, including very slow flow and a slow rising pattern in the systolic phase and a prolonged flow pattern in the diastolic phase. We were able to detect coarctation of the aorta in this patient on the basis of physical findings obtained using transthracic echocardiography and by carefully depicting the aorta. We suggest that abdominal aortic flow pattern provides unique information that is important in identifying coarctation of the aorta.

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We used transthoracic Doppler echocardiography (TTDE) to describe the coronary artery and evaluate coronary circulation by analyzing coronary flow pattern. While many studies report on use of transthoracic Doppler echocardiography in evaluating the distal coronary artery, few evaluate the proximal coronary artery. We describe use of transthoracic Doppler echocardiography in two cases of unstable angina diagnosed in the stenotic region in the proximal coronary artery. Case 1: This case occurred in a 79-year-old man admitted after complaining of chest pain. The electrocardiogram obtained at time of admission showed ST depression in leads II , III, aVF, and V_3-6. The echocardiogram demonstrated hypokinesis at the apex of left ventricular (LV) wall. Coronary Doppler echocardiography showed acceleration flow at the proximal left anterior descending artery (LAD), and diastolic peak velocity at this portion was 104 cm/s. Coronary angiography showed 99% stenosis at LAD#6, the portion of the stenotic region studied using transthoracic Doppler echocardiography. Stent implantation was carried out, and dilatation was successful. No acceleration flow was seen after stenting, and peak diastolic velocity was reduced at 40 cm/s. Case 2: This case occurred in a 59-year-old man who was also hospitalized after complaining of chest pain. The electrocardiogram acquired at time of admission showed negative T wave in leads II , III, and aVF. There was no wall motion abnormality, but acceleration flow was observed in the proximal right coronary artery (RCA), and peak diastolic velocity in this portion was 108 cm/s. Coronary angiography showed 99% stenosis at RCA#1, the portion of the stenotic region studied with transthoracic Doppler echocardiography. Stent implantation was carried out and dilatation was successful. No acceleration flow was seen, and peak diastolic velocity was normalized at 26 cm/s. Transthoracic Doppler echocardiography revealed proximal coronary stenosis directly. Transthoracic Doppler echocardiography was useful in predicting proximal coronary stenosis non-invasively before obtaining a coronary angiogram in patients with unstable angina without ST elevation.

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