We developed a new method to display a potential distribution of the heart activity on the body surface. Electrocardiograms were recorded from many points distributed regularly on the precordial region. From these electrocardiograms three-dimensional graph of potential distribution was produced by a small digital computer and displayed on the CRT. This graph continuously changes with time according to change of potential distribution like an animation. An interpolation method that we had derived took a short execution time and give a smooth approximated curve. Three-dimentional graphs of electrocardiograms were produced for healthy male subjects. From these graphs of electrocardiograms were produced for healthy male subjects. From these graphs a transmission of a wave front of the ventricular activation can be seen an if the wave moves over the picture.

View full abstract

In thirty-three patients including 12 controls and 21"pure"eccentric LVH cases with"chamber enlargement with normal or slight thickening of the left ventricular free wall", the left ventricular end-diastolic volume and the length of the left ventricular major axis at end-diastole correlated to"the spatial R peak time"that is the time of the occurrence of the spatial maximal QRS vector, calculated by the scalar orthogonal leads of Frank using the paper speed of 100 mm/sec, of which correlation coefficients revealed highly close relationship (r=0.88 and 0.89, p<0.001, respectively). In the only patient with pure mitral regurgitation, the spatial R peak time shortened at the postoperative stage and was in parallel with the decrease in angiocardiographic left ventricular cavity size. These observations suggest that (1) the relatively exact cavity size of the left ventricle in"pure"eccentric LVH without combined RVH may be assessed by an exact estimation of the spatial R peak time using the orthogonal electrocardiogram with the paper speed of 100 mm/sec, and (2) this method may have merit in so far as variations in body build influence the QRS voltage measurements which are popularly utilized when diagnosing left ventricular hypertrophy.

View full abstract

Changes in the internal elastic membrane of the coeliac trunk and its branches begin in the foetus. Usually these changes in crease with advancing age. The intensity of involvement varies in different arteries, localized swelling is of particular importance as a measure of atherosclerotic involvement. There is a close relationship between morphology and chemical structure.

View full abstract

1) Factors influencing abnormally prolonged Sinus Recovery Time in Sick Sinus Syndrome were investigated with a microelectrode technique. 2) Although the action of released acetyl choline was confirmed by the effect of atropine and neostigmine on the SRT, an abnormally long SRT like that in SSS was not produced by vagal stimulation in the in situ heart. 3) When the drive rate exceeded a certain value (e.g. two times the spontaneous rate in normal preparations), SA entrance block resulted in less overdrive suppression. When the SA entrance block resulted in less overdrive suppression. When the SA junction is easily blocked with relatively low drive rates, the maximum SRT must be determined within a wide range of drive rates. 4) Verapamil in a concentration of 10^-7 g/ml produced an abnormal SRT suggesting that ionic derangement is one of the factors influencing SRT. 5) A preparation from an aged rabbit with an abnormal SRT revealed fibrosis and reduction in the number of SA nodal cells. The latter seems to be one of the main factors causing a reduction in the potency of the pacemaker and a prolonged SRT in SSS.

View full abstract

In this report, 61 A-V block patients were analysed using HBE. According to the site of the block, these cases were classifed into P(A)-H block, BH block HV block and mixed block. In P(A)H block group (23 cases), the permanent pacemaker implantation was not needed except for one patient with persistent heart failure due to marked bradycardia. Postmortem histology of this patient was well coincident to the results of HBE. In BH block group (18 cases), moderate number of patients were needed to have permanent pacemakers implanted (33%). RA pacing induced split H block with H-V prolongation and varied H and QRS configuration in two cases of this group. These phenomena may be well explained by the longitudinal dissociation theory. In H-V block patients, permanent pacemakers were implanted in all patients (12 cases). In this group, it is difficult to decide the exact location of block, either distal His, bifurcation or bundles, because of the difficulty to record the left or right bundles potentials in clinical practise. Finally, it is important to record the HBE in order to decide the exact site of block, and to choose the suitable therapy for A-V block patients.

View full abstract

Parasystole is an arrhythmia resulting from simultaneous activity of two independent impulse-forming foci, one of which is protected by the other. Ventricular parasystole which arises from an ectopic focus situated in ventricule is relatively common. On the contrary, supraventricular parasystole which is centered in the atria or atrioventricular junction, is extremely rare. Kaufmann and Rothberger studied first parasystole as an entity, ad they reported the firs case of atrial parasystole. However, the first correctly mentioned example of atrial parasystole was described y Jervell. In the previous paper, we described on obsrevation on atrial parasystole and discussed on its consisting-mechanism. The occurrence of ventricular parasystole is not a rarity, since i has been estimated to be present once in every 1, 200 electrocardiograms taken in a general hospital. In contrast, well-documented cases of atrial parasystole are exceedingly rare, and since the first case of it was reported y Kaufmann and Rothberger, only 25 cases have hitherto been reported. In the present paper is described and discussed a case of the extremely rare combination of atrial and ventricular parasystole with exit block and fusion phenomenon.

View full abstract

It has been shown by many authors that afferent stimulation of various somatic nerves results in the different types of responses with regard to blood pressure and heart rate. It was revealed by hunt that afferent "weak" stimulation of the somatic nerves caused depressor responses, and "strong" simulation, pressor responses. Ranson and Gordon thought that the depressor response to the afferent stimulation of the somatic nerves would involve the thick myelinated nerve fibers, and the pressor response, the fine non-myelinated nerve fibers. On the other hand, it has been postulated that the socalled chest pain and/or nonspecific complaints observed in patients with myocardial infarction, angina pectoris and neurocirculatory asthenia (NCA) are related to some alterations at the cervical and thoracic vertebral levels of the spinal cord or nerve roots. Maekawa, Hayase and Konishi attached importance to the presence of subclinical arachnoiditis adhesiva cerebrospinalis at the cervical and thoracic vertebral levels in patients of NCA. These facts suggests that the contribution of the spinal cord and the nerve roots to the circulatory system is different between the cervico-thoracic levels and the lumbar levels. Based on these facts, the author stimulated the somatic nerves of both the forelimbs and he hindlimbs afferently in α-chloralose-anesthetized dogs, with a train of square electric pulses for 20 seconds, and studied the response of the circulatory system to such stimuli.

View full abstract

It has long been demonstrated that in cardiac muscle alterations in the extracellular pH exhibit a remarkable inotropic effect, whereas the precise mechanism is not fully clarified yet in spite of many associated thories. In recent years, however, abundant informations about the processes of excitation-contraction coupling (E-C coupling) of cardiac muscle have been obtained. Accordingly, the mechanisms of inotropic actions of pH on cardiac muscle must also be reexamined on the basis of these lately developed theories of E-C coupling. In the present experiment, therefore, we attempted to elucidate the fundamental mechanism of actions of pH upon several processes of E-C coupling using the bullfrog atrium whose processes of E-C coupling have been fairly well known. The preparation used in the present experiments were the atrial muscle bundles isolated from the bullfrog (Rana cathesbiana). The effects of changes in the external pH on action potential (AP), twitch tension and potassium contracture were observed in one series of experiments, in which AP was developed by means of double glycerol gap method and potassium contracture, by replacing a Ringer solution with a contracture solution containing 100 mM KCl. In the second series, the membrane potential was depolarized to the required levels in order to observe the effects of pH on the membrane currents and contraction. The voltage clamp appratus for the experiment was the same to those used by New and Trautwein (1972a). The pH was set to required values by bubbling with adequately mixtured gases (100% O₂ and 100% CO₂), or by adding the appropriate amount of NaOH to the Ringer solution containing 2 mM each of a acetylglycine, maleic acid and Tris (hydroxymethyl)-aminonethane.

View full abstract