[Fast pathway for heart surgery]. / Vía rápida para cirugía cardiaca.

The increasing demographic and life expectancy rates, together with the vertiginous technological development during the last two decades, have raised the number of cardiac patients requiring surgical treatment. Therefore, several institutions have been forced to give priority to advanced or more serious cases and to postpone those that do not demand an urgent surgery. This analysis was made from June 15, 1999 to June 15, 2000 and demonstrates the results obtained from maintaining a fast track at the National Institute of Cardiology "Ignacio Chávez". This has favored the practice of surgeries in cases with noncomplex pathologies, null mortality, and low morbidity rates. The analysis also compares results from patients who had been subjected to surgery for the same type of pathologies but following the usual course of admittance and surgery scheduling, proving to be cost-efficient. It also demonstrates the high incidence of inter-auricular communication and the Von Willebrand disease that exist in our environment. Based on the results, we propose to maintain and increase this type of surgeries, addressing their limitations.

Evaluation of the response to pharmacological stress in chronic aortic regurgitation.

We evaluated the hemodynamic response of patients with chronic aortic regurgitation and decreased ejection fraction (EF), mean value +/- SD (37 +/- 9), to dobutamine stress echocardiography (DSE). Eleven patients were studied with DSE. Nine patients were in New York Heart Association (NYHA) Class II and two in NYHA Class III. Ten patients received medical treatment in the only other periodic evaluation. With DSE in nine patients, a significant decrease in left ventricular end-diastolic and end-systolic diameters (LVEDD and LVESD) as well as LV end-diastolic and end-systolic volumes (LVEDV and LVESV) was documented in comparison to resting values. EF and fractional shortening (FS) improved significantly with DSE. Systolic wall stress (SWS) and pulmonary arterial systolic pressure (PASP) did not change. Average follow-up was 6.7 months. Three patients underwent valve replacement with mechanical prostheses. Two of them are in NYHA Class I and the other died of LV failure 3 days after surgery. One patient deteriorated beyond surgical treatment and was in NYHA Class II. The other seven patients remain in NYHA Class II and await valve replacement. In patients with chronic aortic regurgitation and depressed EF, the variables relevant to myocardial reserve appear to be EF, FS, LVEDD, LVESD, LVEDV, and LVESV.

Tilt testing in neurocardiogenic syncope: isosorbide versus isoproterenol.

OBJECTIVE: To compare the diagnostic value of pharmacological stimulation with sublingual isosorbide dinitrate and intravenous isoproterenol during tilt testing in patients with neurocardiogenic syncope and with a negative tilt test without pharmacological provocation. METHODS AND RESULTS: One hundred and twenty patients with a history of neurocardiogenic syncope (aged 15 to 77 years) and 50 healthy volunteers (aged 25 to 70 years) were prospectively submitted to head-up tilt (HUT). Those who did not develop syncope or presyncope during passive HUT for 30 minutes underwent repeated HUT with isoproterenol infusion at 4 microg/min (ISOP HUT), for 10 minutes, and, subsequently, were tilted after sublingual administration of 5 mg of isosorbide dinitrate (ISDN HUT) for another 12 minutes. ISDN HUT was always performed after ISOP HUT. Sensitivity and specificity of passive HUT were 41% (95% C.I. 32.9% to 51.0%) and 100%, respectively. Sensitivity of ISOP HUT was 51.4% (95% C.I. 39.2% to 63.6%) and specificity 70% (95% C.I. 55.4% to 82.1%) and for ISDN HUT were 70% (95% C.I. 57.9% to 80.4%) and 88% (95% C.I. 75.7% to 95.5%), respectively. The accuracy of ISDN HUT was significantly higher than the accuracy of ISOP HUT 77.5% (95% C.I. 68.9% to 84.6%). There were fewer side effects during ISDN HUT. CONCLUSION: Sublingual isosorbide dinitrate is at least as sensitive as isoproterenol to assess patients with suspected neurocardiogenic syncope and with a negative tilt test without provocation. The low rate of side effects and the higher accuracy of ISDN HUT, along with the simplicity of this challenge compared to ISOP HUT, suggest that sublingual isosorbide dinitrate should be preferred as a provocative agent to evaluate neurocardiogenic syncope after a negative passive tilt test.

Ebstein's anomaly. Clinical profile in 174 patients.

The study population consisted of 148 patients who did not undergo surgical treatment and 26 who were operated, most of them diagnosed after the age of 2, with a follow-up from 6 months to 25.3 years. Patients were divided in three groups of clinical deterioration according to their functional class and cardiothoracic index (CTR) long-term follow-up in 148 nonoperated patients showed significant differences for mortality between groups I and III (p < 0.001), and between groups II and III (p < 0.02). Predictors of death included the association among functional class III or IV CTR > or = 65% with either cyanosis or arrhythmias (p < 0.05). The multivariate analysis showed that clinical deterioration (p < 0.0001), CTR (p < 0.0002) and functional class (p < 0.001), were significant for mortality. Kaplan-Meier analysis showed a survival rate of 81% in the overall patients free from surgical treatment. According to Kaplan-Meier analysis, the rate of survival was lower in patients with CTR > or = 65% (63.5%), in patients who had functional class IV (52.5%) and in patients included in group III of clinical deterioration (38.2%). Despite the fact that the association of functional class III or IV plus CTR > or = 65% with either cyanosis or arrhythmias is a good predictor for death, the mortality in patients who had only one of these variables was lower. Patients included in group II of clinical deterioration in stable condition presented long survival with medical treatment. Due to the high mortality rate found in group III, surgical treatment of Ebstein's anomaly must be done before deteriorating into group III. Surgical indication must be done considering the surgical risk of each group according to the experience of the Institution and comparing the rate of surgical mortality with the rate of survival without surgery.

[Structural and functional changes in the of heart of high-performance (canoeing) athletes]. / Cambios estructurales y funcionales en el corazón del atleta (canotaje) de alto rendimento.

We studied two groups of healthy subjects: Group I was integrated by 13 high-performance sportsmen (10 men and 3 women), devoted to the discipline of the rowing. Group II was integrated by 16 sedentary healthy subjects. All of them were studied with a two-dimensional echocardiogram, in order to study the anatomical and functional characteristics of the heart. Both groups had similar characteristics in regard of total body area, heart rate and blood pressure, the only difference was in age. The ventricular mass and the diastolic volume were greater in athletes in spite of the fact that the dimensions and transverse thicknesses were similar, this imply a longitudinal increase of the heart size. It is possible that this form of ventricular remodeling has functional advantages. On the other hand, it was demonstrated the existence of physiological hypertrophy without disorders in diastolic function.

Effect of pregnancy on the duration of bovine pericardial bioprostheses.

BACKGROUND: This study sought to evaluate the effect of pregnancy on the rate of deterioration of bovine pericardial bioprostheses. To avoid the fetal and maternal risks associated with anticoagulant therapy during pregnancy, the use of bioprostheses has been advocated for young women with cardiac valve disease who may later wish to bear children. Several reports have suggested the probability of pregnancy-related accelerated deterioration of these valves. METHODS AND RESULTS: The incidence of prosthetic dysfunction and the freedom from deterioration were investigated in 48 women who had 58 pregnancies and in a control group of 167 patients in the same age range. There were 39 cases of prosthetic dysfunction (deaths plus reoperations resulting from valve failure): 12 in the pregnant group for a linearized rate of 3.5% +/- 0.99% (SE) per patient-year and 27 in the control group or 3.4% +/- 0.65% per patient-year (P = not significant). The actuarial freedom from dysfunction was 90.4% (95% confidence interval 77.9 to 96.2) at 5 years and 77.0% (59.7 to 88.3) at 8 years for the pregnancy group and 86.3% (77.3 to 92.0) and 73.4% (56.6 to 84.8), respectively, for the control group ( P = not significant). In the Cox proportional hazard regression analysis, pregnancy did not influence dysfunction. A direct correlation was found between freedom from dysfunction and the patient's age at surgery. CONCLUSIONS: Pregnancy does not accelerate the rate of deterioration of bovine pericardial bioprostheses. It is more likely that biological valves deteriorate more rapidly in these patients because of their young age.

Effects of verapamil in ventricular tachycardias. An experimental and clinical study.

To determine the effect of verapamil in ventricular tachycardias, we performed an experimental and clinical study. Experimental ventricular tachycardias (VT) were produced in dog hearts with minute aconitine crystals introduced into the periphery of a left ventricular area, damaged by intramural injection of 1.0-1.5 ml phenol. The response of these tachycardias to 0.2 mg/kg verapamil was analyzed. Verapamil was infused into the superior vena cava over 15-20 min. Leads II, aVL, intraventricular right and left unipolar records, as well as one of the superior vena cava, were registered under control conditions, in the presence of VT, and after application of verapamil. Recordings were obtained at constant intervals, waiting for the recovery of sinus rhythm (SR) and the posterior reappearance of tachycardia. Experiments were performed for 6 to 8 h under continuous infusion of Hartmann's solution. Throughout these periods, variations in systemic systolic pressure were recorded. From 75 animals submitted to this treatment, 30 (40%) recovered transiently the SR, whereas the drug exerted no antiarrhythmic effect in 19 (25%), and arterial systolic pressure fell importantly in 10 (13%) animals. In two more groups, of 15 dogs each, the VT response to verapamil was compared with the response to lidocaine and flecainide. Endovenous verapamil (5-10 mg) was administered to 10 patients, coursing with VT and having a structurally normal heart, after this arrhythmia was induced by electrical stimulation. The response to verapamil was satisfactory in nine patients (90%), in which VT originated in the septal and apical regions of the left ventricle. Verapamil seems to be effective in experimental and clinical ventricular tachycardias related to calcium-dependent potentials, in which the sustaining mechanism could either be triggered activity or reentry.

[Tetralogy of Fallot in adults]. / Tetralogía de Fallot en adultos.

We present the clinical and hemodynamic profile of 33 patients, older than the 18 year with tetralogy of Fallot. Cardiac catheterization and selective angiocardiography were performed in all cases. We excluded patients with valvular pulmonary atresia associated with tetralogy of Fallot. Most of the patients were in functional class II or IV of the New York Heart Association and all presented with cyanosis. In the electrocardiogram of 23 patients we found right bundle branch block. None had significant cardiomegaly, 19 of 20 cases had reduced pulmonary blood flow and reticular pattern in the lung fields as observed in the chest X-ray. We did not find correlation between the age and the degree of cyanosis, but the level of arterial desaturation correlated with the functional class. The right ventricular systolic pressure was elevated in all patients. In all cases but one the pulmonary arterial systolic pressure were normal of slightly increased. One case with mild pulmonary infundibular stenosis had pulmonary systolic pressure similar to the systemic pressure. Multivariate analysis for functional class showed significant value for cyanosis. Systemic-pulmonary shunt was performed in 10 patients with hypoplastic pulmonary arteries plus reduced pulmonary blood flow, with one postoperative death. We did not find postoperative mortality in patients who underwent corrective surgery. The anatomic and functional behavior of patients who underwent surgery, allowed better tolerance to their heart defects.

[Usefulness of exercise test in programming dual chamber pacemakers]. / Utilidad de la prueba de esfuerzo en la programación de los marcapasos bicamerales.

Prospectively, we studied 42 patient to evaluate the usefulness of treadmill exercise to programme pacemaker DDD in relation to the functioning upper frequency (relation between block frequency of pacemaker and the upper rate frequency). We excluded patient who had no treadmill exercise test after implant pacemaker. During stress 7 (17%) patient presented AV conduction 1:1 (group I); 16 (38%) second degree AV block type Wenckebach (group II); 14 (33%) second degree AV block 2:1 (group III); and 5 (12%) showed inhibition of the pacemaker by intrinsic activity (group IV). Block frequency of the pacemaker in group I and II was superior in regard of the upper rate frequency, 156.85 +/- 22.16 vs 141.43 +/- 20.82 and 135.25 +/- 11.54 vs 121.25 +/- 5.9, respectively. In group III and IV, it was lower, 120.36 +/- 15.31 vs 138.57 +/- 13.29 and 121.0 +/- 7.38 vs 142.0 +/- 14.39. The comparative analysis of the block frequency of the pacemaker in relation with the upper rate frequency showed statistically significant differences (p < 0.05) between groups I and II, and between the group I and III. The appearance of second degree AV block 2:1 is nonphysiologic, is rather due to an abrupt falling in the cardiac output. This phenomenon is able to be predicted and corrected by programming with the use the telemetry with parameters as the AV delay, as well as upper rate frequency and post-ventricular refractory atrial period.

Risk stratification for malignant arrhythmic events in patients with an acute myocardial infarction: role of an open infarct-related artery and the signal-averaged ECG.

BACKGROUND: There is increasing evidence that an open infarct-related artery results in increased electrical stability of the heart and that this effect is at least in part responsible for the favorable outcome of these patients. In the thrombolytic era the optimal strategy for risk stratification remains controversial. This study examined the predictors of serious arrhythmic events during the first year after myocardial infarction. METHODS: A total of 222 patients with acute myocardial infarction, 41.4% of whom were treated with thrombolysis, were studied. At hospital discharge, signal-averaged electrocardiography was performed on 196 subjects and Holter monitoring on 200. One hundred and ninety-seven patients underwent coronary angiography. Left ventricular ejection fraction was determined in 201 subjects. RESULTS: An open infarct-related artery was documented in 106 patients. The incidence of late potentials was 34% (66 patients). Twenty-four patients (10.8%) had an arrhythmic event during follow-up (sudden death in seven, sustained ventricular tachyarrhythmias in 15, unexplained syncope in two). Signal-averaged electrocardiography had a sensitivity of 94% and a specificity of 72% for prediction of arrhythmic events. An occluded infarct-related artery was 78% sensitive and 58% specific, a left ventricular ejection fraction below 40% had a sensitivity of 71% and specificity of 80%, and Holter monitoring was only 38% sensitive and 92% specific. A combination of late potentials plus an occluded infarct-related artery was 68% sensitive and 84% specific. Positive predictive value was low for all variables examined, but could be improved by the combination of several risk factors. The highest positive predictive value was provided by the combination of an abnormal signal-averaged ECG and complex ventricular arrhythmias on ambulatory ECG. On multivariate analysis, in rank order, presence of late potentials, ejection fraction below 40%, high-grade ventricular ectopic activity and an occluded infarct-related artery were predictive of arrhythmic events. CONCLUSION: Among patients surviving an acute myocardial infarction, the occurrence of malignant arrhythmic events can be reliably predicted by the combination of an abnormal signal-averaged ECG, left ventricular dysfunction, complex ventricular arrhythmias on Holter monitoring and an occluded infarct-related artery at the time of hospital discharge.

[Effect of intravenous verapamil in experimental ventricular arrhythmia]. / Acción del verapamil intravenoso en arritmias ventriculares experimentales.

Experimental ventricular tachycardias (VT) were provoked in dog hearts with minute crystals of aconitine introduced into the periphery of an infarcted area, produced by intramural injection of 1-1.5 ml of phenol. The response of these tachycardias to verapamil was studied. Leads II, aVL, intraventricular right and left unipolar records, as well as one on the superior vena cava were registered under control conditions, with VT and after the injection of the antiarrhythmic agent. This injection was infused into superior vena cava over 15-20 minutes. Records were obtained with constant intervals, waiting for the recovery of sinus rhythm (SR) and the posterior reappearance of ventricular tachycardia. The experiments were performed 6 to 8 hs with continuous infusion of Hartmann's solutions. Throughout these periods, the variations of systemic systolic pressure were registered. Of the 75 dogs treated with 0.2 mg/kg of verapamil, SR was recovered transiently in 30 (40%), while it exerted no antiarrhytmic effect in 19 (25%). Arterial systolic pressure fell importantly in 10 animals (13%). In 3 other groups, of 15 dogs each, comparative administration of verapamil vs lidocaine (I), vs mexiletine (II) and vs propafenone (III), was tried. In Group I, verapamil reestablished transient SR in 73% and lidocaine in only 7%; in II, SR resulted from verapamil in 33% and from mexiletine in 7%; in III, SR reappeared in 21% with verapamil and in 28% with propafenone. The repeated positive effect of verapamil was found in 33% of 15 experiments. This drug is effective in certain experimental ventricular tachycardias, probably related to calcium-dependent potentials.

[The action of intravenous flecainide in experimental ventricular arrhythmias]. / Acción de la flecainida intravenosa en arritmias ventriculares experimentales.

Experimental ventricular tachycardias were provoked in dog hearts with minute crystals of aconitine introduced into the periphery of an infarcted area, produced by intramural injection of 1-1.5 ml of phenol near the apex of left ventricle. The response of these tachycardias (VT) to flecainide was studied. Leads II, aVL, intraventricular right and left unipolar records, as well as one on the superior vena cava (SVC) were registered under control conditions, with VT and after the injection of this antiarrhythmic agent. This injection was infused into SVC over 15-20 minutes. Records were obtained with constant intervals, waiting for the recovery of sinus rhythm (SR) and the posterior reappearance of ventricular tachycardia. The experiments were performed 6 to 8 hs with continuous infusion of Hartmann' solutions. Throughout these periods, the variations of systemic systolic pressure were registered. Of the 22 dogs receiving 4 mg/kg of flecainide, transient SR was observed in 12 (55%), while in 4 (18%) this medication had no effect. Heart block presented in 2 animals and a fall of arterial pressure in 4. Of another 25 dogs receiving 2.5 mg/kg of flecainide, similar to clinical doses, transient SR appeared in 11 (44%), while in 3 (12%) SR was not observed. In other 2 groups, each of 15 dogs, the repeated antiarrhythmic action of flecainide was present in 33% with 4 mg/kg and in 20% with 2.5 mg/kg. This medication had no effect in 20% of the former and in 40% of the latter. However the low dose did not produce undesirable effects. Furthermore these differences were no significant statistically. Flecainide is effective in certain experimental ventricular tachycardias probably related to sodium-dependent potentials.

[Bronchogenic cancer at the Hospital General de México. A study of 2 decades]. / El cáncer broncogénico en el Hospital General de México. Estudio de dos décadas.

Among 1,855 thoracic neoplasms seen from 1971 to 1990, there were 923 with bronchogenic carcinoma (CaBr), 50%. The relation male:female was 1.95:1. Sixty three period thirty one percent were male. The histologic type were epidermoid 32.2%, adenocarcinoma 28.4% and small cells 13.2% in men; in women adenocarcinoma 38.9%, epidermoid 28.9% and mixed 7.7% with a significative difference for both sexes for these neoplasms. Other types were less frequent. There is significative difference between smokers and non smokers of both sexes p < 0.001. Epidermoid, adenocarcinoma, small cells, large cells and mixed were the most frequent in male smokers, in women these varieties were more frequent in nonsmokers. Comparison with the reference group with no CaBr suggests that epidermoid, adenocarcinoma and small cells carcinomas have a great possibility to be found in male smokers. Ninety two period two percent of cases were stage III (Tumor Node MetastasIs) with no chance for radical treatment. Only 94 were subject to surgery with 36 total resections. CaBr is an important problem in the General Hospital of Mexico. Antismoking programmes must be stressed in relation to the frequency of CaBr in smokers.

[Variations in hemostasis and fibrinolysis during the treatment of acute myocardial infarct (AMI) with tissue-type plasminogen activator (TTPA). A study of 17 cases]. / Variaciones en la hemostasia y fibrinolisis durante el tratamiento del infarto agudo del miocardio (IAM) con activador tisular del plasminógeno (atPIG). Estudio de 17 casos.

The aim of this trial was to estimate changes in the coagulation and fibrinolysis systems during the thrombolytic treatment with recombinant human tissue-type plasminogen activator (rt-PA) in patients with acute myocardial infarction and correlate with hemorrhagic complications. We studied 17 patients with a 3 hours-continuous systemic infusion of 100 mg of rt-PA. Prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen splits products, plasminogen, alfa-2-antiplasmin (a-2AP) and antithrombin III (AT-III) were performed before, during and after infusion. Most patients showed lengthening coagulation times. Fibrinogen and plasminogen were decreased and PDF was increased. No variations in alpha-2AP or AT-III were observed. The recuperation of fibrinogen levels occurred in 3 hours and there was hyperfibrinogenemia after day 3. No hemorrhagic complication was observed in patients with abnormalities in these coagulation or fibrinolytic tests.

[The treatment of infectious endocarditis. Cefotaxime versus "traditional" medical management]. / El tratamiento de la endocarditis infecciosa. Cefotaxima versus manejo médico "tradicional".

We performed an open study to compare efficacy and renal toxicity of cephotaxime versus the usual beta lactam plus aminoglucoside treatment of infectious endocarditis. Twenty cases were studied, 10 treated with cephotaxime 4 g/day per 21 days and aminoglucoside for only 10 days. Comparison group received a combination of different beta lactam antibiotic plus aminoglucoside for 21 to 50 days, these patients were under care of nonparticipant physicians. Although cephotaxime treatment was as good as conventional antimicrobial scheme for control of infectious endocarditis, the treatment cost increases, and there is only marginal benefit in regard renal toxicity.

[Analysis of rheumatic valvulopathy with scanning electron microscopy]. / Análisis de la valvulopatía reumática por microscopía electrónica de barrido.

There is a high incidence of rheumatic endocarditis in our environment. Therefore it is important to know the structural characteristics of the valvular lesions in order to better understand the physiopathologic pathways of tissue injury. We have chosen a non-conventional method, the scanning electron microscopy. There were very few such reports in the current literature. We analyzed ten mitral valve with rheumatic scarring lesion and five normal, as a control group. We were able to establish three structural patterns. 1) Stone pavement like (endocardium with nuclear bulge cells and marginal folds at the cell boundaries, abundant number of microvillous projections and few areas of endothelial loosening). 2) Cerebroid (subendothelium with wrinkles caused by deformity of the valve with or without endothelial loosening) and 3) Smooth pattern (flattened endothelium with scanty microvillous projections and abundant areas of endothelial denundation and exposition of subendothelium). More damage was noted in the auricular surface of the rheumatic group, characterized by a predominance of the smooth pattern. We found Lambl's excrecences in two mitral leaflets, they were formed by collagen break fascicles of the subendothelium. This technique allowed us to analyze integrity of the endocardial selective barrier and the interactions between the damaged surface of the valve and elements of the peripheral blood and showed more endocardial injury in the rheumatic group. These alterations could play an important role in the pathogenesis of this disease.

[Corrected transposition of the great arteries]. / Aspectos de interés en la transposición corregida de las grandes arterias.

Sixty-nine patients with Corrected Transposition of the Great Arteries were studied, with a mean age of 8.3 years. Forty-nine had atrial situs solitus (SS) and 20 atrial situs inversus (SI). The diagnosis was proved by echocardiography in 28 cases and in all by angiocardiography. In cases with SS, 29 presented ventricular septal defect (VSD), 20 had subvalvular pulmonary stenosis (SVPS), 13 tricuspid regurgitation (TR), 13 atrio-ventricular block (AVB), and seven without associated defects. In cases with SI, 13 had VSD, 14 SVPS, five IT, three AVB, and two without associated defects. The long-term follow-up of the atrioventricular (AV) conduction in 53 cases, ranging between 2 and 37 years (mean 8.3) showed at the beginning of the evaluation 37 cases with normal AV conduction, 14 with first degree AVB, and two with complete AVB. At the end of the follow-up 24 cases had normal AV conduction, 13 first degree, two second degree, four intermittent and 10 complete AVB. The contingency table showed that the possibility of developing changes of the AV conduction was greater in those cases who had an abnormality at the beginning with a relative risk of 2.27 (p = 0.03). Twenty-three cases had SVPS associated with VSD without significant symptoms. During a follow-up ranging from 1 to 20 years (mean 6.5 +/- 5.9), five of these patients were surgically corrected at ages from 6 to 11 years. The remaining cases have had a stable course. At the beginning of the study, 18 cases had TR, and it developed in five more patients during the same follow-up period.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of pravastatin as a hypolipidemic agent in patients with polygenic hypercholesterolemia.

In Mexico, hypercholesterolemia has become a major public health problem particularly in the states of the north of the country and in Mexico City, where a prevalence of 20% has been reported. Schemes of treatment have now been reinforced by the appearance of new cholesterol reducing drugs. The objective of the study was to demonstrate efficacy and safety of a 10 mg daily dose of oral Pravastatin (a new 3-hydroxy-3-methyl glutaryl CoA inhibitor) in a group of patients positive for hyperlipidemia, after 6 months of treatment. Twenty-five patients were included (14 men, 11 women) with an average age of 54 and 50 years, respectively. The main outcome measure was total cholesterol (T-CHOL), low density lipoprotein-cholesterol (LDL-C), triglycerides (TGL), high density lipoprotein cholesterol (HDL-C) and adverse drug reactions report. Twenty-one out of 25 patients completed the study. T-CHOL diminished 21%, LDL-C was reduced by 28%, TGL decreased 6% and HDL-C increased 32%. No adverse reactions were observed throughout the study. Our study shows that the use of a low dose of Pravastatin satisfactorily reduced T-CHOL and LDL-C levels while significantly increasing HDL-C after 27 weeks of treatment, without untoward effects.

[Positive exercise test in hypertensive patients correlated with coronary angiography]. / Prueba de esfuerzo positiva en pacientes hipertensos en correlación con coronariografía.

With the purpose of evaluate the state of the coronary arteries in hypertensive patients with positive exercise test, 82 patients were selected, 50 male and 32 female with mean age of 56.9 +/- 13.2 years. Angiography was normal in 25 patients thirteen patients had a single coronary arteries narrow of less than 50% and 44 cases with significant coronary arteries lesions of more than 50%. The parameters obtained in the exercise test are not significant for statistic purposes. Systolic hypertension or flat response was more frequent in the group with advanced coronary lesions with a predicted positive value in coronary obstructions of 66 and 75%. We conclude that 70% of hypertensive patients have obstructive coronary lesions of some degree.

[Electrophysiologic effect of intravenous propafenone in supraventricular tachycardia]. / Efecto electrofisiológico de propafenona endovenosa en las taquicardias supraventriculares.

The electrophysiologic effects of intravenous propafenone were studied in twenty six patients with supraventricular tachycardias. Ten patients (38%) with intranodal reentrance tachycardia common type, and sixteen patients (62%) atrioventricular orthodromic reentrance tachycardia. Propafenone (2 mg/kg intravenously) given over ten minutes period caused termination of the intranodal reentrance tachycardia in 60% of the cases and 50% to the patients with atrioventricular reentrance tachycardia. The antiarrhythmic effects observed are related to the slowing of the conduction velocity and to the prolongation of the refractoriness in the AV node and accessory pathways preventing the reentrance mechanism. The reinduction of the tachycardia was possible in 46% of the patients. This effects was more significative in the group with accessory pathways (50%), and 40% of the patients with intranodal reentrance. The supraventricular tachycardia was inducible by programmed electrical stimulation in 46% of the patients. None of the patients developed side effects to the administration of the propafenone.