We examined two dogs with Left bundle branch block (LBBB) by conventional echocardiography and tissue Doppler imaging (TDI) to assess cardiac function and interventricular asynchronicity. Conventional echocardiography was used to measure aortic preejection period and pulmonary preejection period (PEP). TDI was performed to assess the long axis function of the ventricles using apical four chamber view. Regions of interest (ROIs) were in the basal segments of the left and right ventricle lateral walls and septal wall. Regional wall motion was assessed quantitatively as myocardial velocities and time intervals. To assess systolic function, peak sustained systolic velocity (Sm) and time from the onset of QRS complex to Sm (Ts) for interventricular synchronicity. In LBBB cases, Ts was markedly longer in basal left lateral segment and basal septal segment than in basal right lateral segment. And Ts of these segments in LBBB cases were also longer than those of the control group. Sm of basal left lateral segment and basal septal segment in LBBB cases were markedly lower than that of basal right lateral segment. And these values were markedly lower than those of the control group. The relationship of the Ts difference in left and right lateral segments with QRS duration was similar to the relationship of the difference in aortic and pulmonary PEPs with QRS duration. Therefore, TDI was considered useful to measure Ts for evaluating interventricular asynchronicity and to measure Sm for evaluating ventriclular motility in cases with conduction disturbance of LBBB.

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The primary objective of the present study was to compare vertebral heart size (VHS) to echocardiographic parameters which were used to monitor the degree of cardiomegaly and cardiac function, to see if there are relationships between them. Medical records of 34 dogs with mitral regurgitation (MR) were reviewed. Used as control were 18 beagles without cardiac diseases. VHS was measured in the right lateral radiographic views of dogs with or without MR There were significant positive relationships to echocardiographic parameters as follow; the end-systolic left atrial to end-diastolic aortic root ratio (LA/AO; r=0.696, p=0.0014), peak E-wave velocity, peak A-wave velocity, cardiac index (CI), left ventricular end-diastolic volume index (LVEdV/BSA), stroke volume index (SVI) and heart rate, respectively. On the single regression line, the ranges of VHS which corresponded to the ranges of LA/AO, peak E velocity, peak A velocity, CI, LVEdV/BSA, SVI and heart rate in dogs without MR were 9.8-10.7, 9.8-11.2, 9.3-10.7, 9.2-10.8, 9.2-11.7, 8.5-11.5 and 7.8-12.4, respectively. It is suggested that the value of VHS corresponded to a status of left sided volume overload in dogs with MR.

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The partial form of atrioventricular septal defect without persistent ostium primum was observed in a 28-day-old female Holstein calf. The heart had a large defect in inlet ventricular septum, and the septum showed a characteristic ‘scooped-out’ appearance. In the atrial septum, the septum primum at the base connected to the limbus fosae ovalis of septum secundum joining the fibrous ring, consequently, the septum primum was not present. The septal leaflet of the left atrioventricular valve was completely divided into discrete anterior and posterior components. While, the septal leaflet of the right atrioventricular valve exhibited an incomplete cleft and produced separate left and right atrioventricular orifices. Anterior halves of both septal leaflets fused to produce a bridging cusp. The posterior component of the left septal leaflet committed to the left ventricle and the right one committed to the right ventricle. Associated cardiovascular anomalies such as double outlet right ventricle, ostium secundum defect, double cranial vena cava, and aberrant origin of left subclavian artery were demonstrated in this heart.

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[in Japanese]

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A case of a nine-year-old spayed Himalayan female, weighing 3.2 kg, on the basis of endocardial hyperechogenicity and accumulation of pleural effusion, the home doctor gave a diagnosis of restrictive cardiomyopathy (RCM) to start a therapy, but without any improvement in clinical conditions, the cat was introduced to Veterinary Medical Teaching Hospital, Nippon Veterinary and Life Science University. The chief complaints at first medical were hypodynamia, anorexia, polyposia and polyuria, rapid breathing and change in eye color. Systolic blood pressure, mean blood pressure, and diastolic blood pressure by noninvasive blood pressure measurement were 223 mmHg, 189 mmHg, and 158 mmHg respectively. From the results of ultrasound diagnosis, blood hormone concentration measurement, and serum chemistry, we gave this case a tentative diagnosis of essential hypertension. However, the existence of mild endocardial hyperechogenicity and irregularity did not allow us to exclude RCM through diagnosis by exclusion at this moment. Treatment was started with diltiazem hydrochloride, angiotensin converting enzyme inhibitor, and dipyridamole. With decreased systolic blood pressure from 210-230 mmHg before treatment to 180-190 mmHg and improved general condition, the same treatment was continued. Endocardial hyperechogenicity at the first medical examination disappeared in the later echocardiography. Therefore, RCM was excluded through diagnosis by exclusion, and consequently, the cat was diagnosed with essential hypertension. The general condition was stable for a while, but systolic blood pressure went over 200 mmHg again, and clinical conditions such as hypodynamia and anorexia appeared. By changing medication from diltiazem hydrochloride to amlodipine besilate, blood pressure immediately decreased and clinical conditions improved. After more than 5 years from the first administration of amlodipine besilate, the cat is maintaining good blood pressure control and clinical status with systolic blood pressure of 130-160 mmHg.

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