Value of the electrocardiographic stress test by atrial pacing in the healing stages of experimental myocardial infarction.

To check up the value of atrial pacing (AP) in estimating the degree of healing in myocardial necrosis, an ECG study was carried out in 20 dogs with experimental myocardial infarction induced by ligation of the left descending coronary artery. The main ECG changes recorded after ligation i.e., Q waves in 14 animals (73%), S-T segment elevation in 14 (74%) and decrease of QRS voltage in 12 (63%), disappeared within a 7-day interval. Anesthesia with Nembutal 56--57 days after ligation and before AP application induced the occurrence of Q waves in 6 animals, S-T segment depression in 18 and T wave inversion in 12. AP during 20 minutes, at a heart rate of 200 beats/min, produced the appearance or the increase of S-T segment depression in 14 animals and T wave inversion in 12. These findings support the assumption that the AP stress test can be used for the evaluation of the necrosis degree in the healing stages of experimental myocardial infarction, but a correct interpretation of the ECG changes induced by AP should also take into account the previous abnormalities due to anesthesia.

Effect of propranolol on experimental periinfarction block and myocardial ischemia.

The effects of propranolol on periinfarction block, myocardial ischemic injury and left ventricular performance following anterior descending coronary artery occlusion were studied. Experiments were made in 14 dogs anesthetized with pentobarbital sodium. Two minutes of reversible myocardial ischemia was induced by occlusion of descending left coronary artery. The severity of myocardial ischemia estimated by summing S-T segment elevation (sigma ST) from epicardial ECG mapping, heart rate, femoral arterial pressure and left ventricular (LV) dp/dt was determined before, during coronary occlusion alone and following propranolol infusion (0.25 mg/Kg) and coronary occlusion. Periinfarction block aspects on epicardial ECG appeared in four dogs following five repeated coronary occlusions. Propranolol infusion before coronary occlusion prevented the periinfarction block in every animal. The decrease of myocardial ischemia (sigma ST elevation), heart rate, arterial blood pressure and LV dp/dt following propranolol and coronary occlusion might be partly due to the beneficial effect of this drug on periinfarction block.

Electrocardiographic diagnosis of experimentally-induced myocardial infarction during cardiac electrostimulation.

The sequential ECG changes were studied by the Sodi-Pallares' method in 10 dogs before and after experimentally induced myocardial infarction of the left ventricle during right and left artificial stimulation. Right ventricular endocardial stimulation produced patterns of left bundle branch block in 9 dogs and of right bundle branch block in one, while left ventricular stimulation caused right bundle branche block patterns in 9 animals. Records during right ventricular stimulation after myocardial infarction showed in the peripheral leads myocardial necrosis only in two animals, while in the epicardial leads necrosis was certain in 2 animals (Q wave) probable in 6 (S-T segment elevation) and suggestive in 2 (T wave negatively). Myocardial necrosis during left ventricular stimulation was evident in the peripheral leads in 2 animals, probable in 6 and suggestive in one. The experimental data suggest that myocardial necrosis can be diagnosed in some cases during right and left ventricular artificial stimulation.

Electrocardiographic diagnosis of experimentally-induced myocardial infarction during cardiac electrostimulation.

The sequential ECG changes were studied by the Sodi-Pallares' method in 10 dogs before and after experimentally induced myocardial infarction of the left ventricle during right and left artificial stimulation. Right ventricular endocardial stimulation produced patterns of left bundle branch block in 9 dogs and of right bundle branch block in one, while left ventricular stimulation caused right bundle branche block patterns in 9 animals. Records during right ventricular stimulation after myocardial infarction showed in the peripheral leads myocardial necrosis only in two animals, while in the epicardial leads necrosis was certain in 2 animals (Q wave) probable in 6 (S-T segment elevation) and suggestive in 2 (T wave negativity). Myocardial necrosis during left ventricular stimulation was evident in the peripheral leads in 2 animals, probable in 6 and suggestive in one. The experimental data suggest that myocardial necrosis can be diagnosed in some cases during right and left ventricular artificial stimulation.

Electrocardiographic diagnosis of myocardial infarction in patients with pacemakers.

The ECG changes of myocardial infarction during permanent or transient right ventricular pacing were studied in 32 patients with transvenous pacemakers who developed myocardial infarction. During right ventricular pacing the electrocardiogram resembled left bundle branch block in 29 patients, right bundle branch block in two, and in one patient the pattern could not be determined. Myocardial infarction induced new ECG changes during pacemaker rhythm in 20 of the 32 patients. There were only QS complexes in 5 cases, ST segment abnormalities in 4 and T wave inversions in 4, negative Q and T waves were simultaneously observed in one patient, Q wave and S-T segment changes in 3 and S-T segment change and T wave inversion in 3 patients. It is concluded that knowledge of the ECG changes induced by myocardial infarction in most patients under artificial pacing can be useful for diagnosis.

Changes of human platelets studied by scanning electron microscopy in acute myocardial infarction.

The formation of platelet aggregates has been suggested to be the initial step in coronary occlusion and the subsequent myocardial infarction (AMI). By scanning electron microscopy we followed: the platelet morphology and aggregation, the macrophage (M) morphology and the lymphocyte (T, B) count and structure in 11 patients with AMI and in 18 patients with unstable angina (UA). Generally, in the patients with AMI, most of the platelets presented relatively frequent (42.5%) or very frequent pseudopodia (35.27%) and the network of surface extensions was associated with several huge platelet aggregates in 6 patients. The mean lymphocyte count was: T = 40.36 +/- 23.95%; B = 28.09 +/- 7.38%; M = 31.54 +/- 21.25%. In the patients with unstable angina the proportion of platelets with pseudopodia was more reduced, namely, that of platelets with relatively frequent pseudopodia was 33.8% and with very frequent pseudopodia was 27.8%. The mean lymphocyte count was: T = 40.30 +/- 20.24%; B = 34.6 +/- 14.39%; M = 25 +/- 10.50%. These data indicate that platelet changes and the formation of aggregates can be an important factor in the occurrence of AMI. The change of immunocompetent cell count in both groups of coronary patients suggests the association of an immunologic process in coronary atherosclerosis.

Effects of verapamil on the acute experimental myocardial ischemia.

The hemodynamic effects of verapamil in conditions of myocardial ischemia and its influence on the atrio-ventricular conduction were investigated in 13 dogs with transient repeated occlusions of the anterior descending coronary artery. Verapamil 0.25 mg/kg was administered after control determinations of heart rate, LV dp/dt, systolic and diastolic arterial pressure and the mean sum of S--T segment elevations recorded by means of 9 epicardial electrodes. Comparison of the differences between the control data and those after occlusion, on the one hand, and those before and after occlusion + verapamil, on the other hand, showed that the drug did not induce significant hemodynamic changes. Arterial pressure was slightly lowered; the increase of LV dp/dt noted after occlusion without verapamil did not occur any more and the S-T segment and T wave disturbances were also less marked, suggesting a protective effect on the ischemic lesion. Larger doses of verapamil (0.50-0.75 mg/kg) induced second and third degree A-V blocks in three animals. These effects could be controlled in two animals by previous or subsequent administration of Carbocromen.

Prognostic value of postextrasystolic potentiation in patients with acute myocardial infarction.

To assess the functional reserve of left ventricle and appreciate prognosis in patients with acute myocardial infarction (AMI) showing ventricular premature beats, the systolic time intervals (STI) and the apexcardiogram (ACG) were determined in sinus rhythm and at the first postextrasystolic beat in 30 patients with AMI (12 mens, 18 women, average age 49 years), distributed into the first three functional classes (Killip), 10 in each class. Location of AMI was anterior in 21 cases, inferior in 1 and anteroinferior in 8. At the first postextrasystolic beat, class III patients showed a lengthening of PEP interval and increase of the PEP/LVET ratio, compared to those in initial sinus rhythm, thus indicating an absence of potentiation; ACG tracings in the same group revealed a lengthening of isovolumic relaxation time (IRT). In classes I and II, both the STI measurement and ACG data indicated the presence of potentiation at the first postextrasystolic beat, manifested by PEP shortening and decrease of PEP/LVET ratio, as well as by a reduction of IRT. Of the patients in classes I and II, only one developed heart failure, while of class III patients, 4 died of heart failure within one year and 3 showed cardiogenic shock on admission. The absence of potentiation in the latter category (with congestive heart failure) is interpreted as a sign of severe prognosis for the subsequent course and outcome of AMI.

[Arrhythmias in patients with mitral valve prolapse]. / Aritmiile la bolnavii cu prolaps al valvei mitrale.

The object of the present investigation was the discovery of the arrhythmias in the patients with prolapse of the mitral valve (PMV), the types of arrhythmias, the factors favouring them, the therapy used. In a group of 126 patients suffering from PMV, 25 had mitral insufficiency, and 48% of the cases had arrhythmias too. The ventricular arrhythmias existed in 18 patients, in the most of them as ventricular extrasystoles. Only in 2 cases, ventricular paroxysmal tachycardia was noticed, and only one case of ventricular fibrillation was recorded. The following conclusions were drawn from the study: the increase of arrhythmias is low, their appearance is correlated with mitral insufficiency, ventricular arrhythmias are predominant, the majority are benign, they are more frequent than in the patients with neurovegetative dystonia (if considering the prolapse associated with systolic murmur), necessity of periodic control for discovering the cases with high risk of ventricular arrhythmias with malignant potential.

The effect of carbocromene on strophanthin-induced ventricular tachycardia in dogs.

The antiarrhythmic effect of carbocromene (Intensain) was studied in 17 anaesthetized dogs. Ventricular tachycardia was induced by infusion of K-strophanthin (mean dose: 154 mug/kg i.v.). In 25 out of 26 experiments carbocromene (4 mg/kg i.v.) was effective. Ventricular tachycardia was converted to sinus rhythm in 16 experiments, to atrial tachycardia in 6 experiments and to junctional tachycardia in 3 experiments. The favourable effect started 8 to 50 seconds after the injection with lower doses of carbocromene (3 and 2 mg/kg i.v.) in time intervals of 5 minutes resulted in similar positive effects leading after 2 or 3 injections finally to a second phase of drug effect where ventricular tachycardia was strongly modified for about 30 minutes. The results favour the therapeutic use of this drug in patients with arrhythmia especially with arrhythmias caused by digitalis.

Beneficial and adverse effects of atropine in patients with acute myocardial infarction.

The action of atropine on heart rate, prevention of arrhythmias, electrical activity and heart contractility was studied in 35 patients with acute myocardial infarction. Atropine had a favourable effect in 24 out of 27 patients with sinus bradycardia, and hypotension present in some cases was improved. Ventricular extrasystoles observed in 12 patients were suppressed within one hour after atropine administration. A--V block was well influenced in 9 of 16 cases. Nine patients with A--V block, of whom 8 with pump failure, presented arrhythmias after atropine. In 12 patients atropine determined a transient enhancing of the ST segment elevation, caused a persistent increase of the Q wave and altered the systolic time intervals by reducing contractility, with subsequent partial return to initial values. The data obtained justify the use of atropine for the improvement of sinus bradycardia, of arterial hypotension and of A--V block. During the effect of the drug there occurred electrical and contractility changes and, in some patients with pump failure, arrhythmias appeared. These observations demonstrate the necessity of monitoring the patients under atropine treatment and of using small doses, repeated if necessary.

[Mitral valve prolapse. An echocardiographic study of 456 cases]. / Prolapsul valvei mitrale. Studiu ecocardiografic a 456 de cazuri.

The prolapse of the mitral valve is an affection arousing much interest from the clinical and echocardiographical viewpoints. The present paper reports on the analysis of 456 cases (322 women--70% and 134 men--29.39%), suffering from prolapse of the mitral valve, selected out of 15,714 echocardiographic examinations (2.93%). All the patients were examined echocardiographically--Echo) in the M mode and bidimensionally; 256 cases underwent an Echo-Doppler examination, too and in 90 cases the phonocardiogram was also used. 983 cases were diagnosed as clinically suffering from prolapse, confirmed by Echo in 291 cases (29.62%), and in 165 cases the diagnosis was established only clinically. Phonocardiographically, the most frequent were recorded the mesotelesystolic click (40%), followed by click + holosystolic murmur (31.11%), telesystolic murmur (19.70%), holosystolic murmur (6.66%). The prolapse of the mitral valve was evidenced in 394 cases, both by M-Echo and by 2D-Echo; in 28 (6.1%) cases it was evidenced only by M-Echo, and in 34 cases (7.4%) only by 2D-Echo. In 62 cases (13.4%) the prolapse was better evidenced when the patients stood. The most affected was the anterior mitral valve, 203 cases (44.5%). The conclusion was drawn that the prevalence of the prolapse of the mitral valve is of 2.93% according to the Echo examination. A correct diagnosis requires the use of a rigorous examination technique and the observance of the clinical and Echo diagnosis criteria.

Study of cardiovascular and auditory pathophysiological implications in a group of operatives working in noisy industrial surroundings.

One third of 160 operatives working in a permanently noisy industrial environment, within the range of 63-8000 Hz and intensity of sound of about 100 db, were found to suffer from a syndrome of neurocirculatory asthenia and 8.1% from arterial hypertension. Study of the ECG according to the criteria of the Minnesota code showed an increased frequency of upward deflection of ST segment (index 9-2) in 20.6% of the cases, depression of the ST segment with an ascending orientation in 50.62% of the cases and left ventricular hypertrophy (index 3-1 and 3-3) in 20% of the cases. Audiometry revealed loss of hearing at frequencies of 4000 CS in 16.1% of the cases. The results obtained suggest that the detrimental effects are not restricted only to hearing, but also that the alterations detected might evolve towards organic cardiac disorders.

Value of systolic time intervals in the estimation of heart failure secondary to acute myocardial infarction.

Serial measurements of left ventricular systolic time intervals (STI) were carried out in 44 patients with acute myocardial infarction (AMI) in the first 5 days after onset, by indirect methods. The patients with heart failure showed significant decreases of ejection time (ET) (p less than 0.001) and of the ejection time index (p less than 0.005) and increases of Wiessler's ratio (PEP/ET) (p less than 0.001). The pre-ejection period (PEP), the isovolumetric contraction time and the total electromechanical systole were unsignificantly changed. Ejection time was shorter than 250 msec in the patients with acute pulmonary edema or congestive heart failure, in most of the patients with flutter or atrial fibrillation and in 16 of the 17 patients who died. Ejection time may have a prognostic significance and may be useful in the early detection of heart failure in AMI. The changes of STI after administration of lanatosid C show the positive inotropic effect of this drug in patients with AMI.

Prognosis of acute myocardial infarction using systolic time intervals recorded on the carotidogram.

The prognostic value of systolic time intervals and of other clinical and laboratory parameters was investigated in 68 patients with acute myocardial infarction (AMI) (55 males and 13 females; mean age 61 years) over a period of one month after onset of the disease. The statistical analysis of data was made by the STR stepwise regression method, using an IBM--360 computer. Finally the study resulted in a stepwise multiple regression equation with 4 factors of maximum statistical significance in the prognosis of AMI: peak SGOT level, age of patients, uncorrected left ventricular ejection time and index of preejection period. This new prognostic index allows a classification of patients with acute myocardial infarction (starting with the second day after onset) into groups of various severity, thus helping the practitioners in the choice of therapy.

Prognosis of acute myocardial infarction using systolic time intervals recorded on the carotidogram.

The prognostic value of systolic time intervals and of other clinical and laboratory parameters was investigated in 68 patients with acute myocardial infarction (AMI) (55 males and 13 females; mean age 61 years) over a period of one month after onset of the disease. The statistical analysis of data was made by the STR stepwise regression method, using an IBM-360 computer. Finally the study resulted in a stepwise multiple regression equation with 4 factors of maximum statistical significance in the prognosis of AMI: peak SGOT level, age of patients, uncorrected left ventricular ejection time and index of preejection period. This new prognostic index allows a classification of patients with acute myocardial infarction (starting with the second day after onset) into groups of various severity, thus helping the practitioners in the choice of therapy.

Study of the immune state in patients with a history of subacute bacterial endocarditis and in their direct relatives. Pathogenic implications.

Immunologic investigations were performed in 18 patients at a mean interval of 1.8 years after cure of subacute bacterial endocarditis (SBE) and in 17 of their direct relatives. The results were compared with those obtained in a control group of 52 healthy subjects. Assay of serum immunoglobulins revealed deviations from the normal (mean +/- 2 SD) in 65% of the post-SBE patients and in 77% of their relatives. Tests for the presence of nuclear, smooth muscle, mitochondrial, cytoplasmatic, albumin and interstitial antibodies showed the presence of such autoantibodies, either single or associated, in 55% of the post-SBE patients and in 58% of their relatives. The serum complement titer was low in 54% of the former SBE patients and in 66% of their relatives. A series of antimicrobial skin tests or intradermal reaction to dinitrochlorobenzene showed hypergy or anergy in 54% o the post-SBE patients investigated. These results, alongside with the data in the literature, support the hypothesis of the preexistence of the immune deficit (probably inherited) in the cardiac patients who develop SBE.

Assessment of hypertension levels control and management (hypertension "AUDIT" project). Study in a population of workers.

The hypertension AUDIT project (WHO) was used for the study of large populations of workers in two Romanian industrial centers, Slatina and Sibiu, constituted into two main groups. The objects of the study were: the detection of new cases of arterial hypertension (AH) and of their proportion as compared with older cases, the assessment of the quality of diagnosis control and treatment methodology as well as the estimation of the patient's attitude regarding the conditions of treatment and of the physician's knowledge and attitude regarding AH. Group I (Slatina) included 22,839 workers and the program was applied in 15,740 randomly chosen subjects. Group II (Sibiu) included 14,874 workers of whom 2,838 were randomly chosen for study. From a total of 606 (6.20%) subjects aged 35 to 64 years with AH in both groups, 494 (81.51%) were older cases and 112 (18.48%) were newly detected. The prevalence of AH was found to increase with age and to be higher in women aged 55 to 64 years. The treatment in older cases from both groups was considered effective in 232 cases (46.96%) (of which 26 (11.2%) with overtreatment) and insufficient in 262 (53%). The reasons alleged by the patients for the late detection of AH were the absence of symptoms and a casual interest for their state of health. The risk factors were systematically checked. Smoking was found in 30.36% of the subjects in group I and in 31% of those in group II. The use of diagnostic laboratory procedures was corresponding to the present recommendations. The nonpharmaceutic therapy was frequently recommended, especially reduction of salt consumption. Besides that, pharmaceutic treatment was indicated in most of the patients (63% in group I and 90% in group II). Diuretics (41.26% in group I and 75% in group II), and beta blocking drugs (35.3% in group I and 70% in group II) were the most frequently administered and in a lesser proportion vasodilators with central or peripheral action, calcium blockers, Rauwolfia and angiotensin conversion enzyme inhibitors. The consumer inquiry showed satisfactory compliance of patients, most of them took their tablets regularly, were satisfied with the medical assistance and preferred to consult the same physician. The data of the physician inquiry regarding diagnosis treatment of AH and professional training also proved satisfactory. The use of the AUDIT project has allowed a complex estimation of AH in the groups studied and will prove useful for a more efficient control of AH in the whole population.

[Infectious endocarditis in mitral valve prolapse]. / Endocardita infectioasa pe prolaps de valva mitrala.

The paper reports on 13 cases of infectious endocarditis in the patients with prolapse of the mitral valve admitted for a period of 10 years (1979-1989) into the Clinic of Cardiology of the Fundeni Hospital. These cases stand for 3.6% of the cases with prolapse of the mitral valve admitted during that period, and 5% of the patients with infectious endocarditis. Our study dealt only with the cases of the prolapse of the mitral valve, clinically and echographically documented before the appearance of the septic graft. The hemocultures were positive in all the patients (viridans streptococci in 84.61% cases). The symptomatology, the clinical objective data and the paraclinical results (phonocardiographic, echocardiographic, electrocardiographic, radiologic, investigations with isotopes), the response to the treatment (medical, surgical) and the evolution in time were analyzed. An increase was found during endocarditis in the number of patients with holosystolic murmurs (30.7% cases) versus those with click-telesystolic murmur, the appearance in 41.15% of the cases of valvular vegetations at the Echo examination, and in 15.38% cases of ruptures of cordages. Mitral insufficiency secondary to endocarditis became worse, in 30.76% cases. The treatment with antibiotics resulted in the healing of the infection in all the cases. The surgery was not necessary in any patient during the evolution of endocarditis. The surgery (valvular prosthesis) was made in 23.07% cases, which presented, after curing the septic graft, important mitral regurgitation with cardiac insufficiency refractory to the medical treatment. Prophylaxis of the infectious endocarditis in the prolapse of mitral valve with mitral regurgitation is necessary.