Background. Standard multiplane transesophageal echocardiographic probes have large transducer tips that could increase patient discomfort, especially during esophageal intubation. A miniaturized biplane probe has been developed for pediatric use; however, its utility for adult patients is unknown.
Methods. The miniaturized biplane imaging was tested in 48 anesthetized, ventilated adult patients during cardiac surgery and was compared with the standard multiplane imaging. We evaluated the image quality of cardiac structures and thoracic aorta using a five-grade scoring system. We also measured the left ventricular end-diastolic dimension (LVEDD, mm) and the peak flow velocity (cm/s) of the left atrial appendage (LAA) by pulsed-wave Doppler.
Results. Esophageal intubation with the multiplane probe was unsuccessful in 1 patient, although this patient was successfully intubated with the biplane probe. There were no complications with either probe. The image qualities of the left ventricle, mitral valve, aortic valve, and ascending aorta by the biplane probe were inferior to those by the multiplane one. On the other hand, left atrium (LA), LAA, interatrial septum, aortic arch, and descending aorta were as well visualized by the biplane probe as by the multiplane one. The values of LVEDD and peak flow velocity of LAA were not different between the probes. LAA thrombus in 2 of 47 patients and aortic dissection (Stanford type A) in 7 were also well detected by both methods.
Conclusions. The resolution of the two-dimensional images in the near fields of the miniaturized biplane probe was as good as the standard multiplane one. The miniaturized biplane probe was found to be applicable to the detection of LA or LAA thrombus and assessment of LAA function in adults.

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Background. Although collateral circulation is important for myocardial salvage in acute coronary syndrome, effects of collaterals are significantly reduced by systemic hypotension. The objective of this study is to evaluate the effects of nitroglycerin and nicorandil on micro-collateral circulation during systemic hypotension.
Methods. Real-time myocardial contrast echocardiography (MCE) was performed in 15 open-chest dogs during occlusion of the left circumflex artery using a snare. Ischemic area was identified using high ultrasound power exposure (burst) just after coronary occlusion. Micro-collateral vessels were recognized by re-opacification during 30 seconds of occlusion. Final subjects for this study were 8 of the 15 dogs that displayed micro-collateral vessels. Flow volume of the donor artery, i.e., the left anterior descending coronary artery (LAD), was measured. Video intensity (VI) were measured and percent wall thickening (%WT) was calculated. Replenishment curves of VI for the ischemic area after burst were obtained and used in the exponential function y=A (1-e^-βt), for estimation of myocardial blood flow volume (A×β). These indices were compared at control and during hypotension after nitroglycerin (0.01-0.02 mg/kg) or nicorandil (0.1-0.2 mg/kg) administration.
Results. Equivalent hypotension was induced by each drug. VI, %WT and A×β at the ischemic area were significantly decreased after nitroglycerin (p<0.05) administration, but not after nicorandil. Nicorandil increased LAD flow from 6.1 ±2.3 ml/min to 8.8±2.1 ml/min, but nitroglycerin did not.
Conclusion. Compared with nitroglycerin, nicorandil offers better preservation of coronary collateral circulation, even during systemic hypotension.

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Background. Three-dimensional (3D) echocardiography is an ideal tool for the assessment of morphology and function of the cardiovascular system including the geometry of the mitral apparatus. However, quantitative assessment of deformity of the mitral apparatus has been performed on a two-dimensional plane obtained from the 3D dataset, in spite of its unique configuration. We developed a novel software, which allowed us 3D visualization and quantitative analysis of the geometry of mitral leaflets and annulus by using transthoracic real-time 3D echocardiography.
Methods. We examined 6 normal subjects and 6 patients with dilated cardiomyopathy with functional mitral regurgitation (DCM-MR) by using this system.
Results. We succeeded in all study subjects to demonstrate the mitral leaflets and annulus in the 3D geometrical view. Furthermore, we could measure curved annular circumference, curved annular surface area, annular height, and the mitral leaflets tenting volume from the 3D data.
Conclusions. 3D geometry of the mitral leaflets and annulus were clearly demonstrated and quantified by our novel anatomical image creation system by using transthoracic real-time 3D echocardiography. This technique may be applicable to 3D quantitative analysis of the mitral apparatus for decision making in surgical strategy in each patient with mitral valve disease and may be useful in further investigations regarding the mechanism of functional mitral regurgitation.

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A 30 year old man was admitted because of electrocardiographic abnormalities. Echocardiography revealed left ventricular aneurysms at the apex and the mid-inferior wall. The histological diagnosis by endomyocardial biopsy was sarcoidosis. Treatment with prednisolone was done. This is a rare case of multiple left ventricular aneurysms due to sarcoidosis, which was detected early by echocardiography.

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We present a case of aortic dissection associated with systemic infection. Transesophageal echocardiography demonstrated calcified stenotic aortic valves and dissection of proximal ascending aorta that filled with an echoic mass, which was found as an abscess caused by methicillin-resistant staphylococcus aureus. We suspected that the jet flow of aortic stenosis combined with systemic inflammatory disease contributed to intimal tear and dissection of the aortic wall that led to the development of abscess inside the false lumen in the particular patient.

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