[Electro-vectorcardiographic aspects of diastolic and mixed overloads of the right ventricle]

We studied 400 cases of isolated atrial septal defect without severe pulmonary hypertension, in which the diagnosis was established by the hemodynamic data and it was proven by surgical findings in 257 instances. High fidelity unipolar thoracic and intracardiac records, as well as vectorcardiographic curves in three planes, were obtained. Different types of right ventricular conduction disturbances, which were present in all cases, as well as certain electro-vectorcardiographic aspects related to ventricular depolarization and repolarization, were analyzed. Mean angles of the resulting vectors at 60 msc of the ventricular activation, were determined relating to the types of block. The following points should be emphasized: Besides the right proximal blocks, which are more frequent, right distal ones can also be diagnosed by the presence of slurred R wave and delayed onset of the intrinsicoid deflection in only some right leads. The monofascicular and parietal right blocks are observed when the diastolic overload of the ipsilateral ventricle is low. The activation time of the anterior inferior right septal mass generally permits an objective classification of the degree of a right proximal block. The prolonged Q-Tc interval only in right leads, seems to be a function of the magnitude of the right ventricular diastolic overload.

[Rupture of the ventricular septum following acute myocardial infarction]

Septal rupture (SR) during acute myocardial infarction (AMI) was found in 23 patients of 4 300 consecutive cases of AMI. In 55% the SR was diagnosed clinically by the appearance of a murmur, in 23% by shock and in 22% by heart failure. Eventually every patient developed a pan-systolic murmur. In 82% of the cases the murmur was best heard at the lower left sternal border. In half of the patients the location of the murmur suggested the possibility of papilary muscle rupture or dysfunction. In 68% of cases the rupture occurred during the first week after the onset of AMI. Cardiac catheterization was performed in 17 patients, pulmonary hypertension was found in all of them. Pulmonary blood flow was twice the systemic blood flow (P less than 0.005). Coronary angiograms performed in 6 patients showed three vessel disease in 5 cases. Five patients underwent surgery. Three of them survived. All of the 17 patients who had medical treatment died. Ten within the first week after AMI, 5 within the first month and 2 late deaths. Autopsy was performed in 15 cases. Eighty percent had coronary narrowing in several vessels. SR measured between 5 and 20 millimeters in 78% and was found in the anterior septum in 61%. In the cases who were in shock, the ventricular myocardium was extensively damaged. We conclude that once the diagnosis of SR is established, the patient should undergo surgical closure of the SR and coronary revascularization if necessary. Early surgical indication is particularly important in patients at risk of developing shock.

[Coronary thrombolysis in acute myocardial infarction. Initial experience with an intravenous thrombolytic agent]

Thirteen patients with less than 5 hours of the onset of symptoms of acute myocardial infarction underwent selective coronary angiography. Ten of them had angiographic signs of coronary thrombosis. In these ten patients 15 mgs of an acylated streptokinase-plasminogen complex (BRL 26921 Beecham Farmaceuticals) were administered intravenously. Total angiographic recanalization was observed in 7 patients. The coronary arteries involved were the left anterior descending in 4 cases and the right coronary artery in 3. In 8 out of the 10 patients significant diminution of injury pattern in EKG was registered, however in all of them the necrosis pattern supervened. Prolongation of the thrombin and thromboplastin times, as well as an important fibrinogen disminution were documented in all instances. There were not complications related to the administration of the drug. An increase of muscle enzimes was documented in all cases. The follow-up was uneventfull with excellent results in all the patients. This study proves that with IV trombolitic therapy coronary recanalization can be achieved in the mayority of the patients; however there is no question that myocardial infarction finally ocurred. We speculate about the possibility of avoiding infarction by the administration of the drug within the first hour after the onset of the symptoms.

[2-dimensional echocardiography in fixed fibrous subaortic stenosis. Correlation with hemodynamics and M-mode echocardiography]

Comparative diagnostic capacity is analyzed between two dimensional echocardiography (E-BD), hemodynamics, surgery and the M-Mode, to accurately establish the diagnosis, variety and severity of fixed fibrous subaortic stenosis, in 29 patients, whose previous diagnosis were made by two dimensional images, using paraesternal, apical and subxiphoid long axis. Group I is made up of 17 patients who had two dimensional echocardiography, M-Mode, and catheterization; Group II is composed of 12 patients who only had two-dimensional echocardiography and M-Mode. Within Group I, hemodynamics showed subaortic gradient in 81%, transvalvular in 13% and no gradient in 6%; the ventriculography showed subaortic obstruction only in 59% of the patients and was normal in 41%. The M-Mode echocardiography registered protosystolic aortic closure (CPSAo) in 50%; the subaortic obstruction was seen as a band, in 44%, non-specific echoes in the outflow tract in 12% and this was normal in 44%. The two cases with transvalvular gradient, the M-Mode registered the subaortic band, and in the case without gradient, the ventriculography showed the subvalvular obstruction. In Group II, the diagnostic signs of M-Mode were: CPSAo in 58%, band in 17%, non specific echoes in the outflow tract in 8%, and this was normal in 75%. The results support other data in that two-dimensional Echocardiography is more sensitive and more specific than M-Mode, intraventricular pressure curves and ventriculography.(ABSTRACT TRUNCATED AT 250 WORDS)

[Collateral pathways in patients with univascular coronary obstruction (2)]

We found 10 coronary collateral pathways in patients with right coronary (RC) obstruction. The communication with the anterior descending (DA) through the septum was the most prevalent. 5 pathways were found in the presence of DA obstruction, again the communication with the RC through the apex was the most frequently observed. Only 2 pathways were found in the presence of circumflex (Cx) obstructions.

[Functional significance of collateral coronary circulation in univascular obstructions (1)]

The presence, degree and functional significance of the coronary collateral circulation was investigated in a group of 68 patients with angiographycally important (greater than 60%) univascular coronary obstruction. The following clinical parameters were reviewed. Smoking, hypertension, diabetes mellitus, functional class (NYHA), and degree of angina pectoris. In the ECG the presence of abnormal Q waves and the response to the stress test were analysed. To evaluate the functional significance of the collateral circulation the following angiographic and hemodynamic parameters were measured: ejection fraction (FE 100), mid sistolic ejection fraction (FE 50), percent of regional shortening of the left ventricular wall and finally the end diastolic pressure. According to the obstructed vessel (R, DA, Cx) the degree of obstruction (parcial or complete) and the degree of collateral circulation (O, I, II, III) several groups were formed. Statistical analysis of all the above mentioned clinical, electrocardiographic and angiographic findings were compared amongst the various groups. Coronary collateral circulation was demonstrated in 45 patients (68%) being present in 82% of those with complete coronary obstruction. In most of the patients (87%) an abundant collateral network was present (grade II or III). No statistical differences were demonstrated between the groups with abundant or poor collateral circulation in all the clinical, electrocardiographic or angiographic parameters. Finally we conclude that important collateral circulation usually develops in the presence of severe coronary obstruction; however its functional value is limited.

[Measurement of tricuspid transvalvular flow by M-mode echocardiography and its application in the calculation of the A-V shunt in interatrial communication]

Previous studies have demonstrated that it is possible to measure the cardiac output by M-mode echocardiography (M-echo), using the echogram of the mitral (MV) or aortic valves. In this communication we pretend to demonstrate the possibility of calculating the right cardiac output by the echocardiographic image of the tricuspid valve (TV). We studied patients with atrial septal defects (ASD) because the anatomic and physiologic conditions allowed us to obtain a complete record of the TV. The study was done in a prospective form with 12 patients with isolated ASD, without pulmonary hypertension, cases with ostiumprimum were excluded. The measure of stroke volume of the MV and TV was made using Rasmussen's formula and mechanic planimetric measure of the diastolic opening area of both valves. For the TV area calculation it was considered that the area of the posterior valve was similar to the septal valve and the area of the last one was multiplicated by 2, in this form we obtained the value of the whole TV. For confirmation of the reliability of this method, we studied 8 healthy subjects for the comparison of the mitral and tricuspid flows. The velocity of the transvalvular flow was obtained by measuring the D-E slope. The correlation between MV and TV flows was good in healthy subjects (r = 0.957). Similar results were obtained with the areas of MV and TV in the same group (r = 0.971). In patients with ASD, the comparison between Rasmussen's method and the planimetric method showed that the value of TV increased higher than the MV values. The difference is most important between the areas. The correlation of the cardiac output calculated by the Fick method and M-echo was not significative. The defective output determined by catheterization and M-echo showed a significative correlation (r = 0.793). It is possible the quantitation of the right ventricle output by M-echo, this technic is useful because it shows the hemodynamic conditions of patients with ASD, and it is possible the measure the TV flow, and probably it will be useful in patients with other congenital heart disease with left right shunts.

[Left ventricle function in isolated mitral stenosis. Regional angiographic study during the ejection phase]

Twenty two patients with rheumatic mitral stenosis and 12 healthy individuals were studied, using the following parameters: 1) Basal (B), Medial (M) and apical (A) mean velocity of circunferential shortening (VMAC); 2) Ejection fraction (EF); 3) Mid-systolic ejection fraction (FE 50); 4) Relative ejection fraction (REF = FE 50/FE). The student T comparing the patients with mitral stenosis to the control group showed statistical difference in all the parameters studied, but in the M and A, VMAC. In 13 patients (59%) the EF and the REF were found diminished, on the other hand, the EF 50 was definitively abnormal in 19 patients (86%). Twenty one patients (96%) showed abnormalities at least in two of the mentioned parameters and finally, only one had normal ventricular function. We conclude that the ejection ventricular function studied with "regional" indexes is almost always abnormal in patients with mitral stenosis.

Twelve years of experience with cytotoxic therapy in malignant tumors of the neck and head

Since 1968 we have treated with antiblastic drugs 164 malignant tumors recurrent or incurable by surgery or radiotherapy in 151 cases. Different therapeutic methods were employed. Today we have the possibility of selecting alternative options with incipient or relatively delimited carcinomas, principally the substitution of radical surgery by initial associated physical and chemical treatment, so that if there is a cure the consequences of radical surgery can be avoided. We emphasize the curve of two primary cancers of the uvula with 300 mg bleomycin exclusively and the results observed in oropharyngeal and laryngeal carcinomas by using three intermittent Schabel cycles and 4,000 rad Telecobalt, avoiding a radical surgery.

[Late arrhythmias in the operated interatrial communication. Analysis of sinus node function and the conduction pathways by His bundle electrocardiography]

Four hundred patients with atrial septal defect treated surgically were reviewed. Thirty five (8.7%) developed arrhytmias post-surgery which persisted for over a year. Sinus bradycardia was found in 10 patients, nodal rhythm in 21, and atrial fibrilation and flutter in 4 patients. Thirty five per cent of the patients with late arrhythmias developed related symptomatology. In 14 patients the function of the sinus node was studied with electrical stimulation of the atrium and with His registry. The interatrial conduction time, AV node and His Purkinje were analized employing various stimulation frequencies. All the cases studied had normal intra-atrial conduction; the response of the atrio-ventricular node to increasing frequencies was normal, an the intraventricular conduction remained constant. In 8 patients (52%), alterations of the sinus node were found; these consisted of prolonged post-stimulation pauses, Wenckebach's type sinoatrial block and suppression of sinus automatism employing vagal procedures or through electrical stimulation. A patient with severe bradycardia detected by dynamic electrocardiography had to be treated with a permanent pacemaker. We confirm that these arrhytmias are not produced by lesions of the internodal tracts, and that an alteration of the sinus node is frequent without a concomitant lesion of the intraventricular pathway. The lesion to the nutrient artery could be due to trauma and/or surgically induced. The response to anticholinergic drugs was good. Prolonged observation of these patients could increase the morbility of these arrythmias and raise doubts of the surgical indications in cases with moderate hemodynamic repercussion.

[Apical hypertrophic myocardiopathy. Report of the first case identified on the American continent]

What appears to be the first case of hypertrophic apical myocardiography described in the western hemisphere is presented in this report. The diagnosis was confirmed by angiocardiography and echocardiography. The electrocardiogram showed the characteristic giant T waves. It is of interest that the coronary radioangiography suggested alterations in the microcirculation which could explain the striking electrocardiographic pattern of subepicardial ischemia seen in these patients.

[Hemodynamic effects of atrial overstimulation in patients with ischemic heart disease]

Auricular over-stimulation is used by some researchers to study patients under suspicion of coronary heart disease. In this paper we discuss the changes in telediastolic pressure of the left ventricle (PT-DVI), stimulating the right auricle with increasing frequencies sent through an external pacemaker. When the ventriculography and coronarography were over, the Sones catheter was left into the left ventricle. An electrode-catheter was introduced through vein in the right auricle, the distal end being very close to the sinusal node, where the electric catch as accomplished. Through this stimulator the cardiac frequency was increased in 20 heart beats more than the basal cardiac frequency and the PTDVI was simultaneously measured every 3 minutes. Through the coronarographic study, the patients were classified in: normal, bi-vascular and tri-vascular. The increase and decrease of PTDVI was calculated in relation to the results obtained during the last minutes of over-stimulation compared with the basal figures. Most of the patients showed a decrease in PTDVI no matter what the vascular engagement was. Our results show there is no difference between the response and the coronary obstruction degree so, this evidence is of no value to judge the functional situation of the left ventricle.