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C Malacarne

Publications and source records attributed to C Malacarne.

28 records · Page 2Linked to original sources
PubMed1977

[Evolution of ventricular depolarization in the acute phase of inferior and posteroinferior myocardial infarction (author's transl)].

Twenty-five patients, hospitalized within 24 hours from the beginning of the precordiaglia due to acute diaphragmatic infarction, with or without a posterior extension, underwent the ECG and VCG recordings for the first consecutive twenty days and on the fortieth day, in order to study the development of ventricular depolarization. To diagnose an infarction of the diaphragmatic and posterior walls the usual ECG and VCG paramaters were used; the ECG was found to be less useful above all for the difficulty of measuring the variations, in the loss of the electrical forces. The electrodes were always placed in the same points suitably signed. Several evolutive modalities of the diaphragmatic infarction were observed; in 52% of the cases the loss of the inferior electrical forces reaches its maximum expression quickly, then it remains almost constant. In 12% of the cases the necrosis increases very clearly, tardily, between the ninth and fourteenth day. In 24% a precocious reduction of the electrical extension of the infarction on the eighth-twelfth day is observed. In 12% of the cases there are irregular oscillations during the whole acute phase. In all cases more or less stressed daily or cyclic oscillations were present. In nine cases an extension of the infarction to the posterior wall was evident; among these in five, two peaks are present; in two an initial increase, in the other two an initial decrease of the electrical extension of the necrosis; then, more or less stressed daily or cyclic oscillations. In another nine cases a single reading of the tracings do not let us diagnose a posterior extension; this is possible only through an "in series" reading. The clinical course and the humoral data do not give any contribution to the interpretation of the founded evolutive variabilities. The necrosis, therefore, must not be considered a zone of homogeneous and global stuffing, but composed of cellular groups in several and variable anatomo-metabolic situations conditioning the observed electrical instabilities.

Acute Disease↗
PubMed1977

[External recording of His bundle electrical activity (author's transl)].

A noninvasive method to record His' potentials in man is described. In several patients who needed intracardiac recording, a bipolar lead was placed across the chest, directed as conveniently as possible for the recording of His bundle electrical activity. A signal filtered (70-300 Hz) and amplified (X 100.000), was processed by a multichannel analyzer for averaging. The temporal regime of the averager was determined by a trigger which established a fiducial point on the ECG. For this purpose a QRS detector fed to a normal peripheral bipolar lead was used. The temporal stability of the system was continually checked in order to reject the recordings over the limits of +/- 1 msec. The computer program was chosen in order to select a window (usually 200 msec) which occurred up to 150 msec prior and 50 msec after the trigger signal. The sampling rate was 5 KHz for 1024 samples and the sweep counts were fixed from 128 to 512. At the same time, the D1, D2 and D3 were recorded in the other three channels of the analyzer for a more accurate measurement of the HV interval. Then an example comparing the external and interval recording was presented. Finally several external recordings were measured and the exact reproducibility of the G wave was confirmed. In conclusion we can say that the G wave is significant and suggests the electrical activity of the bundle of His.

Bundle of His↗
PubMed1976

Left ventricular parietal block: diagnostic and clinical study.

Fifty-five patients with widened QRS complexes due to the presence of slurred S waves or of terminal slurrings on R waves, in more than three leads, with no infarction or bundle branch and fascicular blocks, were studied with the usual clinical examinations as well as vectorcardiographic recording. A parietal block of the left ventricle was diagnosed when, in the presence of a normal development of ventricular depolarization in the initial and middle phases, the terminal QRS loop was delayed, sometimes irregular and displaced leftward and posteriorly. When this delay was directed to the right, the ventricular localization was puzzling. The comparison of the electrocardiographic (ECG) and vectorcardiographic (VCG) data on the terminal part of ventricular depolarization showed some discrepancies and revealed the greater importance of VCG investigation for the study and the localization of parietal blocks. The pathogenesis of such minor conduction disturbances is not yet clear, since the experimental data on the anatomical-functional structures are different: the Purkinje network, Purkinje fiber-muscle junction or common myocardium. In some cases we think it is possible to localize the structure concerned; in any case we can always localize it at the level of the free ventricular wall.

Adolescent↗
PubMed1976

[Problems of fascicular asyncronism in advanced left bundle branch blocks with marked axial deviation towards the left (author's transl)].

Twelve patients, showing advanced left bundle branch blocks with axial deviation toward the left (beyond -45 degrees) were studied by clinical, radiological and vectocardiographic examinations. All of them showed a marked cardiomegaly and half of them had also severe congestive heart failure. The left axial deviation may be connected to an asyncronism of the left ventricular activation, due to a delayed excitation of the antero-superior wall because of a lesion of the anterior fascicle. The authors think that this asynchronism of the activation should be evident in ECG test by a more delayed intrinsecoid deflection in aVL than in V6, as has been previously pointed out in the isolated anterior fascicular block. This ecgraphic datum was found in two patients only. The other possible causes of a left axial deviation in advanced left bundle branch block are discussed.

Aged↗
PubMed1975

[Diagnostic difficulties of isolated left posterior hemiblock(author's transl)].

Out of 4000 vectorcardiograms, 23 of them showed the most tipical pattern of left posterior hemiblock (BFP). According to the vectorial characteristics, they were divided into 5 groups; only two groups (for a total of 8 cases) showed, according to the Authors' opinion, the characteristics of the isolated BFP. The diagnostic difficulties of such a conduction disturbance are discussed since, it simulates, the vectorial pattern of the vertical heart. Moroever there is an underlining possibility that conduction disturbances in the right heart coexist in many cases of supposed isolated BFP with marked axis rotation to the right. The Authors agree with the hypothesis already expressed by Polu on the vectorial progress of the isolated BFP which should have an AQRS of about 70 degrees; an exact electrocardiographic diagnosis might be therefore impossible.

Echocardiography↗
PubMed1975

[Left bu;ndle branch block with right axial deviation. Clinic and electro-vectorcardiographic study (author's transl)].

Eleven patients whose ECG and VCG showed a left bundle branch block with right axial deviation (between + 90 degrees and + 150 degrees) were studied with clinical and radiological investigations. All of them had pathological abnormalities of cardiopulmonary apparatus and cardiac enlargement, but only one had congestive heart failure. The right axial deviation was due in one case to the vertical position of the heart in the chest and in three cases to conduction defects of the cardiac impulse through the left bundle branch. In the remaining cases the right axial deviation was dubious. The authors present and discuss all possible factors which could cause such deviation of QRS axis in the left bundle branch block.

Aged↗