PubMed Health⌕ Search

Biomedical subjects

S Férez

Publications and source records attributed to S Férez.

At least 19 recordsLinked to original sources
PubMedDate not supplied

[Antiarrhythmic effects of verapamil].

The effect of verapamil were studied on 50 episodes of supraventricular and ventricular tachycardia in 44 patients. An i.v. dose of 0.10 to 0.15 mg/kg. was used. In 5 cases His bundle electrograms were obtained while maximal dp/dt was determined in 7 others. Sinus rhythm was obtained in 21 (81%) of 26 cases of PSVT. In all cases of rapid atrial fibrillation (n-11), an important decrease in the ventricular response was elicited. Of 7 cases of atrial flutter, verapamil induced sinus rhythm in 3 and a significant decrease in the ventricular rate in 3 others. In 2 out of 6 cases ventricular tachycardia reverted to sinus rhythm. The latency time between the injection and the manifestation of the effect ranged from 2 to 4 minutes. A slight and short-lasting depression of dp/dt was observed in all cases studied. Verapamil produced an increase in the A-H interval in 4 of the 5 cases studied with His bundle recordings. Verapamil was found to be a useful drug to suppress PSVT, to decrease the ventricular response in flutter or atrial fibrillation and to convert some ventricular tachycardias to sinus rhythm. Verapamil should be used with caution in previously digitalized patients and is contraindicated when there is S-A node dysfunction as in the tachycardia-bradycardia syndrome.

Adult↗
PubMedDate not supplied

[Myocardial injury caused by reperfusion].

Arterial coronary occlusion produces ischaemic changes, and alter the aerobic metabolism, creatinephosphate depletion and accumulation of anoxic metabolites in the ischaemic tissue, with an alteration in the calcium regulation. With the recovery of the blood flow, the myocardial ischaemic injury and infarct zone are diminished, leading to an improvement of survival. The adverse effect induced by the reperfusion of ischaemic cells with the production of free radicals and dearrangements in the glucose metabolism, fatty acids and intracellular calcium flow as well, has been proven. There are 4 kinds of reperfusion damage: stunned myocardium, reperfusion arrhythmia, no-reflow phenomena, and cellular death, all of them with a particular physiopathology. Nowadays, there are too many paraclinics in order to reach a diagnosis, and perhaps the only available treatment is still under research. This field has great expectancy in the future. In this article, some of the contemporary concepts are reviewed.

Humans↗
PubMedDate not supplied

[Results of the Census of Hemodynamic Services and Interventional Cardiology 2000 in the Mexican Republic].

We present the results from the National Census of cardiac catheterization and interventionist Cardiology Services performed by the Chapter of interventional Cardiology of the Mexican Society of Cardiology up to the year 2000. The present document identifies the total number of existing services, their physical characteristics and available human resources, as well as the number and type of procedures performed in them.

Cardiology Service, Hospital↗
PubMedDate not supplied

[Detection of early occlusion of aortocoronary by-passes. Usefulness of a non-angiographic method].

A total of 83 bypasses were studied. Angiographic results demonstrated occlusion in 3 of 24 bypass of internal mammary artery placed in the anterior descending artery, 2 in the right coronary artery, 1 in the posterolateral of the circumflex and 1 in the first diagonal branch, with a total occlusion average of 8.4% within the first 8 days. We found a good correlation between the coronarographic angiograms and the positivity or negativity of the echo-electrocardiographic tests, during atrial pacing. We believe that this simple method could be done routinely in all the patients after coronary surgery, to decide the need of a new coronary angiogram. Furthermore, this study shows that the occlusion of a single coronary bypass does not produce myocardial infarction, detectable by enzymatic measures or by resting EKG. This method also detects the early post-operatory sinus sick syndrome.

Adult↗
PubMedDate not supplied

[An assessment of myocardial ischemia in women with the exercise test validated by coronary angiography].

Ischemic heart disease has been studied in men and women only as a group. We studied the sensitivity and specificity of the exercise stress testing in women. The exercise stress testing (EST) was validated with the coronary arteriography. We studied 72 women and 129 men, the mean age was 55 years for women and 51 years for men. We found in women 83.2% of estimated maximal heart rate; the rate pressure product was 2.4, no different from the values recorded in men (p greater than 0.06). The blood pressure response to exercise was higher in women, and the maximal work capacity was more elevated in men (p less than 0.006). We found normal coronary arteries in 41 women, 70.7% with a positive (EST) compared with a 87.07% in men. The sensitivity and specificity of the exercise stress testing for the diagnosis of ischemic heart disease is smaller in women.

Coronary Angiography↗
PubMedDate not supplied

[Exercise test in patients with permanent pacemakers].

From June 1988 to June 1990 we studied fifty patients who had implantation of a pacemaker. (31 females and 19 males). All of them underwent stress test with Bruce's protocol. Patients were divided in two groups; pacemaker-independent (PI) and pacemaker-dependent (PD). Over 50% of the patients inhibited the pacemaker with their own rhythm, most of them had sinus dysfunction. Complete A-V block was predominant in PD. The group of PI achieved more mets and had more oxygen consumption. Blood pressure response was similar in both groups.

Adult↗
PubMedDate not supplied

[The clinical features of myocardial infarct via "normal" coronary angiography. The experience of the Instituto Nacional de Cardiología].

The end-point of our study was to find clinical differences between patients with myocardial infarction and evident obstructions in coronary angiography, and patients without coronary obstructions. In a 10 years follow-up period, 48 patients with diagnosis of myocardial infarction and normal coronary arteries by angiography (group A) where admitted al hospital. We compared this group with 80 patients (group B), randomly selected from all patients with myocardial infarction and evident obstructions in coronarography. Patient age at the ischemic event, familiar history of ischemic heart disease or sudden death, obesity, drug habits, contraception drugs use, and history of migraine and Raynaud's phenomenon were pointed out. Thirty patients from group A were admitted with acute myocardial infarction, and we also analysed in these patients prodromal symptoms, precipitating factors, AMI localisation, serum enzymatic levels, rhythm and/or conduction disturbances, clinical condition, treatment and new ischemic events. Group A patients showed lower age-average, smoking habit, prodromal symptoms and serum CPK levels. They have better ventricular performance parameters and a greater incidence of women. The only different risk factor for ischemic heart disease between both groups was smoking.

Age Factors↗
PubMedDate not supplied

[Value of the exercise test in asymptomatic myocardial ischemia].

To evaluate the predictive value of ischemic ST segment depression without associated chest pain during exercise testing, data were analyzed from 7305 studies. Two hundred thirty six patients were included in this study and were separated in 2 groups. Group A consisted of 169 patients without chest pain who, during exercise testing, showed a positive ST segment response (at least 1.5 mm of horizontal or downward ST segment depression for at least 0.08 second, compared with the resting baseline value), and Group B consisted of 67 patients who had both chest pain and a positive ST segment response. Selective coronary angiogram was performed on all patients. Each Group was separated into 3 sub-group according to the Cohn criteria: sub-group I (asymptomatic persons 8.3 vs 19.4%); sub-group II (patients with history of Myocardial Infarction 36.7% vs 19.4%); sub-group III (patients with chronic angina 55% vs 61.2%). The clinical characteristics, coronary risk factors, distribution of coronary artery disease, and exercise test response were similar in both groups. During treadmill exercise, the mean heart rate was 140.6 +/- 22 in group A versus 127.1 +/- 23 in the group B. The pressure-rate product was 2.4 +/- 0.8 versus 1.9 +/- 0.5, respectively (P less than or equal to 0.05). The predictive value for severe coronary artery disease of an exercise test in patients with asymptomatic ischemia was 77.5% as compared with 89.6% in the group with angina. This study confirms the high frequency of asymptomatic myocardial ischemia during exercise testing, compared with patients who had angina during exercise testing, with high percentage of prediction (77.5%) for coronary artery disease.

Aged↗
PubMedDate not supplied

[Predictive value of sudden death in repetitive ventricular extrasystole].

Prognostic significance of repetitive ventricular premature contractions (RVPC) were evaluated retrospectively in 452 patients studied with a 24 hours continuous electrocardiographic monitoring (Holter System). The patients were analysed in two groups: Group 1.- 199 patients; with primary heart disease: previous myocardial infarction (MI) in 114 patients, angina pectoris (AP) in 29 cases, congestive cardiomyopathy in 19 cases (COCM); hypertensive heart disease (AHCD) in 14 cases, Atherosclerotic heart disease (AEC) with conduction disturbance and without angina pectoris 23 cases. Group 2.- 253 patients without heart disease. Two different types of RVPCs were defined: Type A: as the occurrence of self-terminating two (coupled) or multifocal. RVACs Type B: Self limited ventricular tachycardias or "R on T phenomena". Forty patients of group 1 had RVPCs (23 type A and 17 type B) and 22% of them had sudden death (SD). Among 199 patients with structural heart disease, 74 had congestive heart failure (CHF) and 12 of these had RVPCs. 83% of patients with RVPCs died suddenly. No patients with CHF and without RVPCs had SD. In group 2 (without heart disease no patients died on the follow up, and 6% of them had RVPCs (68% type A and 32% type B). Coronary arteriographic and ventriculographic findings were reviewed in 92 patients with previous MI. In the patients followed 40 has RVPCs, and 9 of them had SD. Those 4 cases were cases of MI (25% of the patients with MI having RVPCs), 4 (25%) with COCM, and 1 (2.5%) with hypertensive cardiac disease. Thus, patients with MI or COCM had higher incidence of RVPCs, so they are at a high risk for sudden cardiac death.

Cardiac Complexes, Premature↗
PubMedDate not supplied

[Predictive value of ventricular extrasystole in the exertion test and its relation to the magnitude of coronary damage].

The predictive value of ventricular arrhythmias, associated with treadmill exercise testing was evaluated in 115 patients undergoing coronary angiography and left ventriculography within three months of the exercise test. 39 patients with ventricular arrhythmias (at least one premature ventricular complex, paired complex or ventricular tachycardia) had a higher or multivessels disease than the patients without ventricular arrhythmias (P less than 0.05). This study demonstrated that ventricular arrhythmias detected at exercise testing are related to the extent of coronary artery disease, and the presence of the left ventricular disfunction.

Cardiac Complexes, Premature↗
PubMedDate not supplied

[Asymptomatic myocardial ischemia].

The concept, physiopathology, epidemiology, diagnostic procedures, prognosis and treatment of asymptomatic myocardial ischemia are reviewed. Hypotheses given to explain the absence of pain in the presence of myocardial ischemia are analyzed; Cohn's classification of asymptomatic myocardial ischemia is described and complemented with other clinical entities of painless myocardial ischemia. Prevalence of asymptomatic myocardial ischemia in different groups of patients is also discussed as well as the most important characteristics of diagnostic procedures. Finally the prognosis of asymptomatic myocardial ischemia is analyzed and the present therapeutic possibilities are discussed.

Coronary Disease↗
PubMedDate not supplied

[Continuous electrocardiographic recording during a first parachute jump].

The behavior of the cardiac rhythm under intense stress was studied with continuous electrocardiographic recording during the first jump with an automatic parachute in 13 members of the Universidad Nacional Autónoma de México sky diving club. There were 12 male (92.3%) and one female (7.68) with an average age of 22.8 years. A complete clinical history, 12 lead electrocardiogram and a treadmill stress test were performed two weeks before jumping. A two-channel Holter recording system was hooked up 30 min. before boarding the airplane and was turned off one hour later. The heart rate values were compared two weeks prior (64.5 beats/min), before (112.8 beats/min), during (170 beats/min) and after the jump (122.8 beats/min). The mean difference between each phase was statistically significant with p less than 0.001 values. The observed cardiac rhythm was sinus tachycardia in each case. In six cases (43.6%) 22 episodes of sudden decrease of the heart rate were seen and there were no major rhythm or conduction disturbances. The urinary catecholamines were similar in nine cases (69.2%) after the jump (x 51.2 micrograms/100 ml) and two weeks later in four control cases (x 10.3 micrograms/100 ml). We concluded there were no significant rhythm disturbances in the presence of an intense but brief stress condition in young healthy people. This study was classified as longitudinally, descriptive, experimental and projective.

Adult↗
PubMedDate not supplied

[The Wenckebach phenomenon in patients with acute myocardial infarction].

To show the incidence of second degree Auriculoventricular block (AVB) with Wenckebach phenomenon (WF) 1336 patients with acute myocardial Infarction (AMI) were studied. We found 67 cases with WF 5.0% from the total group of AMI and the 33.83% form the group with any type of AVB. Fifty three were male and 14 female (4:1). 77.5% arrived to ICU for their first AMI and 22.38% for their second AMI. 43.26% were posteroinferior with extension to right ventricule; 36.0% pare posteroinferior, 10.4% anterolateral; 9.0% posterolaterals and 1.4% lateral. The onset time of WF in relation to the AMI set was 64.2% in the first 24 hours; and 17.9% for the 24-48 hour group as well as for those over 48 hours. The duration of the WF in 43.3% was lees than 24 hours 19.4%; between 24-48 hours; 25.4% more than 48 hours and 11.9% was transient. The WF was always present with heart rate under 110x'. In 9 patients it occurred with sinus bradycardia with a 48 to 40x' heart rate. The QRS duration was from 80 to 90 msec in 91.0% and from 100 to 120 msec in 9.0%; 4.47% of them had right bundle branch block previous to WF. 10.4% had progression to Mobitz II and 11.9% lead to complete AVB. Mortality was the 2.98% in the group their first AMI; and 4.47% in the group with their second AMI.

Adult↗
PubMedDate not supplied

[Diagnosis of ischemic heart disease by infusion of isopropylarterenol: comparison with ergometry and validation by coronary arteriography].

In order to evaluate isopropylarterenol infusion (ISO) as a diagnostic procedure in ischemic heart disease, we performed a clinical study in 54 patients controlled with exercise stress test (ERGO) and validated by coronary arteriography. Eighteen patients had normal coronary arteriographic findings and 36 had coronary artery disease. In both groups the hemodynamic response was similar in either test used (ERGO or ISO), when similar heart rates were reached. The sensitivity of ERGO was 80.55% and 86.11% for ISO and specificity of 77.72% and 72.26% respectively in the diagnosis of coronary artery disease. When both tests are associated their sensitivity is 83.30% and their specificity is 75.0% (Table V). The ISO test was not accompanied with adverse effects and could be considered as a useful method in the diagnosis of coronary heart disease, similar to ERGO. Additionally ISO could be applied to understand some physiopathological mechanisms of ischemic heart disease.

Adult↗