[Anatomo-functional substrate of high risk arrhythmia after myocardial infarct]. / Sustrato anatomofuncional de las arritmias de alto riesgo tras el infarto de miocardio.

Ventricular arrhythmias detected in the late-hospital phase of myocardial infarction have been identified as a risk factor for sudden death, being their prognostic value independent of ventricular function. However, relations between both factors are not clarified. In order to study hypothetic associations between ventricular arrhythmias and some clinical, hemodynamic and angiographic variables, 60 patients (52 males, 8 females) underwent 24-hour Holter recordings and cardiac catheterization with left ventricular and coronary angiographies, 3-5 weeks after hospital admission. Past history data, acute phase complications and hemodynamic and angiographic results were compared between patients with and without significant ventricular arrhythmias during Holter monitoring (10 or more PVC's/hour and/or repetitive forms). No significant differences were found between both groups neither in mean age nor in the incidence of previous angina or infarction, cerebral ischemia, diabetes, lipid disorders or subjective feeling of being under psychological stress. Prior history of arterial hypertension was, however, significantly more frequent in patients with ventricular arrhythmias (53.3% vs 17.8%; p = 0.0183). No differences were observed in the localization of the infarct or in the complications during the acute phase (CPK peak, Killip's score, angina after 24 hours of evolution, intraventricular or A-V conduction disorders and supraventricular and ventricular arrhythmias). Among hemodynamic data, only left ventricular and aortic systolic pressures were different in both groups, being significantly higher in patients with ventricular arrhythmias. There were not differences in left ventricular segmentary contraction and in number of coronary vessels involved. To conclude, significant ventricular arrhythmias were recorded in 25% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[Calculation of the mean pressure of the pulmonary artery and of the valve surface by ECG in mitral stenosis]. / Calcul de la pression moyenne de l'artère pulmonaire et de la surface valvulaire par l'E.C.G. dans le rétrécissement mitral

From a group of 50 patients affected by pure mitral stenosis with sinus rhythm, we have tried to obtain multiple correlation equations which enable in to calculate, in each particular case, the mean pressure of the pulmonary artery and mitral valvular area from purely electrocardiographic facts. In an additional group of 16 patients we have been able to verify the mentioned equations, placing all the calculated points within the presumed limits of tolerance. So it appears that the electrocardiographic calculation of these hemodynamic parameters is possible, with sufficient approximation for clinical requirements.

[QRS in mitral stenosis: Electrohemodynamic correlation]. / Estudio del QRS en la estenósis mitral: correlaciones electrohemodinámicas

The electrocardiograms of 50 patients with mitral stenosis in sinus rhythm were reviewed (axis of QRS and T in the frontal and horizontal planes, with each one of their modules, Lewis index and right Sokolow-Lyon, quotient R/R + S in V1, time of beginning of the intrinsecoide deflection of QRS), they were related with the hemodynamic data; and the existence of clear relations between both methods of exploration were confirmed. 1. The QRS axis in the frontal plane kept a good relation with the hemodynamic data (mainly thzontal axis there proved to be a closer relation than in this one. 2. The quotient R/R + S in V1 was the parameter that best correlated with the mean pressure of the pulmonary artery and with the pulmonar capillary pressure. 3. Although the right Sokolow-Lyon index is not a definite criterion for recognizing a right ventricular hypertrophy; it is very useful in correlating the total pulmonary resistances with the mean pulmonary arterial pressure, even if it did not reach pathologic values. The same can be said the Lewis index, although the dependence is less important. 4. The horizontalization of the frontal axis of T becomes more important with the increase in the hemodynamic repercution. 5. As an expression of the systemic hemodynamic alteration, the decrease in time of inscription of the intrinsecoid deflection, of the left ventricle in V6 became evident when the mitral area diminished or by increase of mean pressure of the pulmonary artery. 6. The electrocardiographic characteristics that allow to recognize the existence of a mitral area smaller than 0.8 cm2, with a possibility of error of less than 5% (false positives), are: -- a horizontal axis of QRS less or equal to + 9 degrees -- a right Sokolow-Lyon index of more than 21.56. 7. The existence of a mean pressure of more than 25 mm. Hg in the pulmonary artery can be acknowledged, with a possibility of false positives of less than 5%, by the apparition of one or more of the following data: -- a frontal axis of QRS more or equal to + 87 degrees -- a Lewis index of less than -7.44. 8. The diagnosis of mean pressures of the pulmonary artery of more than 35 mm. Hg can be established, with the same degree of possibility, by: -- a T frontal axis of less or equal to + 10 degrees -- a horizontal axis of QRS of less or equal to + 13 degrees -- a right Sokolow-Lyon index of more than 19.71 -- a quotient R/R + S in V1 more or equal to 0.88. 9. The only finding that permits to establish of a pulmonary capillary pressure higher of 25 mm. Hg, with false positives possibility of less of 5% is: -- quotient R/R + S in higher or equal to 0.07 in V1.