The accuracy and the reliability of an indirect method for non-invasive measurement of blood pressure in dogs were investigated in this study. Ten male beagles (age : 18 months, body weight : 8.6 to 13.1 kg) were used. Indirect blood pressure was measured with an automated oscillometric method (DINAMAP 1846 SXP, KRITIKON) in all dogs, and direct blood pressure was measured with a pressure transducer (TP-200 T, AP-641 G, RM 6000, Nihonkoden Kogyo). Which was connected to the polyethylene tube previously inserted into the femoral artery of the experimental hypertensive dogs.
The results obtained were as follows.
1) A cuff with 4.6cm width and 13.1cm length was selected as the most suitable one among the four dfferent in size.
2) A significantly high correlation was obtained between the direct (actual) and the indirect (oscillometric) blood pressure measurements when the above-mentioned cuff was attached to the forelimb.
3) In the three consecutive measurements of blood pressure, the value of the last measurement tended to be lower than those of the first two measurements.
4) The blood pressure values measured at right lateral recumbent position were significantly lower than those at suspended or rearing position.
5) In the dogs used in this study, diurnal variation in blood pressure was not obvious.

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This study was performed to ascertain the influences of pentobarbital sodium anesthesia on the rectal temperature, respiratory rate, heart rate, blood pressure, hematological parameters and electrocardiogram in beagle dogs up to 48 hr after anesthesia.
Five beagle dogs (age: 11 months, body weight: 8.0.-11.2 kg) were given intravenously 25mg/kg of pentobarbital sodium and were anesthetized for approximately 2hr. They were completely awakened from anesthesia 6 to 8 hr after the administration. Rectal temperature, respiratory ratea nd blood pressure in four normal dogs significantly declined under anesthesia and recovered 8hr after administration. Circulating number of red blood cells, white blood cells and platelets also decreased in number under anesthesia. The heart rate increased transiently for 30min after the administration, and the elevation of ST segment in electrocardiogram was observed apparently for 4hr.
In one dog with Spontaneous arrhythmia (ventricular premature beat), the values of the above-mentioned parameters showed change similar to those in normal dogs, but with no more increment of arrhythmia.
From these results, it is presumed that electrocardiographic examination is needed for monitoring the dog under pentobarbital sodium anesthesia because the anesthesia may cause myocardial hypoxia.

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Anatomical closure of the foramen ovale (FO) was studied in cattle and full-term fetuses.
In the fetal hearts, FO was a large short tube connecting the left caudal portion of the right atrium to the right cranial portion of the left atrium. It was covered by the septum primum and the septum secundum.
After birth, the cranial part of the septum primum became thicker and was constricted and subsequently fused with the septum secundum at the cranial end of FO. The fusion extended backward. After closure of FO, the caudal part of the septum primum persisted as the fossa ovalis, forming the caudal part of the atrial septum.
In Holstein cattle, the earliest closure of FO was observed in a 17-day-old calf and FO was closed in most cases exceeding three months of age. In Japanese Black cattle, the earliest closure was observed in a 19-day-old calf, but the time of anatomical closure of FO varied among individuals.

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A technique was devised to obtain a stable ambulatory electrocardiogram from a dog neither anesthetized nor constrained. Fissuly, an improvement of the jacket was made to prevent the electrodes from detaching during the recording of the electrocardiogram. An innovation of a foreleg sleeve fitted to beagle's body measurements successfully prevented the detachment of the electrodes.
Next, a comparative study was carried out the three lead methods, A-B, M-X and supplementary, to be used for protracted electrocardiography. The study was completed by analyzing the beagle electrocardiograms obtained by these three lead methods over a period of 24 hours.
With the A-B lead, the base line in the electrocardiogram fluctuated according to the dog's movements 315 times during 24 hours, the fluctuation being the most marked among the three methods. The R wave diminished in height remarkably and the S wave increased in depth impairing the effectiveness of the analysis.
The supplementary lead proved inappropriate, because the base line fluctuated by breath-impedance changes and affected the analysis.
The M-X lead was better than the other two methods. The base line fluctuation was minimal 26 times during 24 hours, less than 10% of the fluctuation in the A-B lead.
We have thus succeeded in devising a technique for obtaining a satisfactory electrocardiogram over a period of many hours, by using the M-X lead and attaching the renovated jacket to an unanesthetized and unconstrained beagle.

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Ccontinuous recording of ECGs was performed for 24 hours in ten healthy beagles under the non-anesthetic and unconstraind condition, using a Quiuk-Corder QR-1200 (Fukuda M. E KOGYO Co., ) and a specially designed jacket. Circadian rhythm of the heart rate and that of ST segmental and arrhythmic manifestations were analyzed from the recorded ECGs using Analyzer Model 1230 (Zymed). The results obtained were as follows:
1. Heart rates were divided into a low heart rate period from 23:00 to 9:00 and a high heart rate period from 10:00 to 22:00. Thus, the heart rates tended to decrease during the midnight through early morning and to increase during the daytime.
2. ST levels generally dropped during the midnight through early morning and tended to increase during the daytime through evening. This correlated sligthly with the heart rates. The ST slopes, however, showed significant variations among individuals, with no specific trend over a period of 24 hours.
3. Arrhythmias including sinus arrhythmia, sinus tachycardia, sinus bradycardia, sinus arrest, ventricular premature beat and second-degree A-V block were found throughout the experimental period. Sinus tachycardia was observed during the daytime through evening. On the other hand, sinus arrhythymia, sinus bradycardia, sinus arrest, ventricular premature beat and second-degree A-V block were noted mostly during the midnight through early morning.

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Two cases were presented with the same chief complains of sudden dyspnea and hind-Leg paraplegia, subjected to echocardiographic examination. One of them showed a thrombotic echogram in the left atrium and the other in the left ventricle. The cat which showed a thrombotic echogram in the left atrium died later, and necropsy revealed that a thrambus existed exactly in the left atrium. In both cases, a thrombus was found in the externaliliac artery ; one case at necropsy and the other at surgery.

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Endocardial fibroelastosis (EFE) has been recognized more commonly in infant, young cats and dogs than in adult. Although EFE has been reported in adult human, there has been only one report of EFE in adult cat. We present the case of adult cat with EFE with unknown etiology.

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A Two-month-old female Shih Tzu (Case 1) and a three-month-old-female Maltese (Case 2) with systolic ejection murmurs were referred to Azabu University Animal Hospital. Physical examinaiion, ECG, PCG, X-ray echocardiography and angiocardiography were carried out for clinical diagnosis. Case 1 dog was diagnosed as the severe valvular and light infundibular pulmonary stenosis (PS). However, the dog survived fro 42 months with digitalis and resting in cage. Case 2 dog was not diagnosed while in life, but the dog was confirmed to be in the Tetralogy of Fallot (TOF) by postmortem examination. While observation of the prosess, the right heart failure was progressing in each case. Case 1 dog died 42 months after the first medical examination, caused by the pulmonary edema for the heart failure, and Case 2 dog died 24 months after, a traffic accident.
At autopsy, in case 1, the right atrial and ventriclular enlargement caused by the severe pulmonary stenosis with adhesive leaflet was found. In case 2, there was a severe enlargement of the right atrium and ventricle. Parietal band was shifted to the outflow tract and pulmonary stenosis was formed by this abnormal muscle. VSD was also located near a membranous part under the conus (6×5 mm). Therefore case 2 dog was diagnosed as the Tetralogy of Fallot morphologically.

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