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P Delise

Publications and source records attributed to P Delise.

72 records · Page 4Linked to original sources
PubMed1980

The anterior displacement of the QRS loop as a right ventricular conduction disturbance. Electrophysiologic and vectorcardiographic study in man.

Anterior displacement (AD) of the QRS horizontal loop (Frank VCG method) was induced by programmed right atrial stimulation (PRAS) in 15 cases. When AD occurred we noticed changes of the terminal QRS vectors and of the T loop similar to those observed in incomplete right bundle branch block (RBBB). The increasingly anticipated extrastimuli induced progressively the AD and then progressive degrees of RBBB. The anterior shifting of the efferent limb never appeared after the induction of RBBB. A left conduction disturbance never appeared after the AD. In cases of supposed incomplete left bundle branch block (i.e. left ventricular hypertrophy) the QRS duration decreased when the AD was induced. Therefore, the AD induced by PRAS and probably those observed in some clinical cases are due to a right ventricular conduction disturbance.

Adult↗
PubMed1980

[Accelerated idioventricular rhythm wih isorhythmic A-V dissociation. An electrophysiological study (author's transl)].

Three cases of accelerated idioventricular rhythm with isorhythmic A-V dissociation are presented. One case was affected by hypertrophic non obstructive myocardiopathy and two cases were affected by coronary heart disease with previous myocardial infarction. In all the cases of the arrhythmia persisted for days or months. By means of the electrophysiological study we could establish that 1) the focus was not protected by entrance block and 2) it was localized in the main branches of the conduction system. In the first case the focus was localized in the right bundle branch, in the second case, it was localized in the anterior fascicle of the left bundle branch and in the third case in the posterior fascicle of the left bundle branch. These electrophysiological characteristics suggest that the arrhythmia was due to increased firing of normal idioventricular pacemakers. On the basis of this electrogenetic interpretation we outline that in our cases the term of accelerated idioventricular rhythm should be preferred to others used in literature such as slow ventricular tachycardia.

Adult↗
PubMed1979

The role of left ventricular conduction in the electrogenesis of left ventricular hypertrophy. An electrophysiologic study in man.

Various electrocardiographic and vectorcardiographic (ECG-VCG) patterns of ventricular conduction disturbances are inducible by premature right atrial stimulation (PRAS). These patterns are a consequence of different degrees of refractoriness in the specialized ventricular conduction system. We observed that the intermediate phase of left bundle branch block (LBBB) induced by PRAS in 20 subjects with normal basal QRS (complexes) were similar to those of left ventricular hypertrophy (LVH). In 18 patients with basal ECG-VCG signs of LVH, right bundle branch block (RBBB) induced by PRAS produced a progressive disappearance of these signs and the "normalization" of the tracings. The initial maximum QRS vector decreased, disappeared or remained absent in the patients with LBBB induced by PRAS, and appeared (when absent in the basal VCG) and remained unchanged (when present) in patients with RBBB induced by PRAS. In this paper we discuss the electrogenetic implications of these data. The ECG-VCG sings of LVH are probably dependent on a slowed conduction in the left bundle branch system, while anatomical hypertrophy per se probably plays a less important role.

Adult↗
PubMed1977

[Evolutive study of the vectorcardiogram from the 14th day to the 6th month of life on the normal infant].

With the purpose of a better evaluation of the changes of cardiac potentials during the early hemodynamic arrangement of the normal heart, the authors analyze the VCG of 10 normal children periodically recorded from the 14th day to the 6th month from birth. Rotation of QRS, T and P loops in the three planes, direction and voltage of principal planar and spatial vectors were analyzed. The QRS loop showed a balanced distribution between right and left ventricular forces in the second week and developed a leftward orientation from the 4th week to the 3rd month, as demonstrated both by the loss of clockwise rotation of horizontal QRS loop and by the progressive leftward and backward direction of intermediate vectors. The initial vectors were sketched or absent in the 14th day and increased successively until the typical Q loop. The voltage of terminal vectors did not change in the course of time, but the S loop in the horizontal plane lost its original clockwise rotation and shifted to middle posterior line. The T loop progressively shifted backward so that it was always posterior after the 30th day. The P loop in the frontal plane was similar to the adult's one while in the horizontal plane it often presented a figure-of-eight. The semeiological aspects and the electrogenic considerations of these changes were discussed.

Age Factors↗
PubMed1977

[The mechanism of the chronic supraventricular tachycardia: an intracavitary electrophysiological study (author's transl)].

Chronic Supraventricular Tachycardia (CST) or Chronic Atrial Tachycardia is a relatively rare arrhythmia. Because of very poor number of cases studied with electrophysiologic techniques its mechanism is still debated. Three cases of CST, one of persistent type and two of repetitive type, are reported. His bundle electrogram, high and low right atrial electrograms and atrial stimulation were performed in every case, ventricular stimulation in only one case. The Amiodarone, Pindolol, Verapamil and vagal manoeuvres effects were evaluated in all cases. The site of origin of tachycardia, atrial in cases 1 and 3 and junctional in case 2, was estabished by atrial map. The electrophysiologic findings suggested the presence of an ectopic focus in cases 1 and 3 and of an AV nodal re-entry circuit in case 2. Our results and those of the literature indicate that the site and the mechanism of CST, as in paroxysmal supraventricular tachycardia, is not univocal. Their electrophysiologic evaluation by means of endocavitary techniques can allow a more satisfactory therapeutic approach.

Adolescent↗
PubMed1976

[The vectorcardiogram of the normal child, 2-12 years of age (author's transl)].

Morphological aspects and the most important vectorial parameters of the VCG (Frank method) of normal children, aged 2 to 12 years, were analyzed. The total group consisted of 110 subjects (10 for each )ear) subdivided into three subgroups of progressive age. Semeiologic evaluation of the QRS in the frontal and sagittal planes was not significant because of the stereotypes of the figures. In the horizontal plane the majority of cases showed typical triphasic development of the vectorial groups, while biphasic morphology was found in the minority. The triphasic loop presented 1) a balance between anterior and posterior forces which was more frequent in the youngest children, 2) a posterior orientation which was more frequent in the oldest children or 3) an anterior orientation which was infrequent. Since the anterior orientation of triphasic QRS was not related to the age -- it may also be seen in normal adults -- it was attributed to a variation of ventricular activation. The biphasic loop was attributed to immaturity of ventricular conduction. The evaluation of quantitative parameters was in agreement with the results of other studies. The changes of initial and intermediate vectors were probably due to the more important development of the left ventricle. The QRS duration increased with age. The T loop was posterior in the majority of the youngest children and progressively advanced with age, although it remained posterior in an important number of cases of children aged twelve.

Age Factors↗