Biomedical subjects

V Araya Gómez

Publications and source records attributed to V Araya Gómez.

6 recordsLinked to original sources

PubMedDate not supplied

[Auricular flutter associated with an interatrial septal aneurysm submitted to radiofrequency ablation].

We present the case of a young man who began with type I atrial flutter, he had no response to antiarrhythmic drugs. The echocardiogram showed an atrial septal aneurysm in the region of the fossa ovalis. We performed an electrophysiologic study which showed an atrial flutter with atrial rate of 257 bpm, and 2:1/3:1 AV conduction. The flutter waves were negatives in leads II, III and a VF (type I atrial flutter). An endocardial mapping was obtained in order to localize the area of slow conduction. It was located in the isthmus of atrial tissue bounded by the inferior vena cava and the tricuspid valve annulus in the low posterior septal right atrium. In this area we applied radiofrequency energy in 10 occasions but the arrhythmia was not suppressed. With atrial pacing we achieve a concealed entrainment and then resumption of atrial flutter after cessation of pacing. After another 6 applications of radiofrequency in this same area in sinus rhythm, we paced the atrium without inducing any form of arrhythmia. He was asymptomatic 15 days later, but one month after the ablation, the flutter reappeared, we performed a second successful radiofrequency ablation. In this time he was asymptomatic.

Adult↗

PubMedDate not supplied

[A new electrocardiographic algorithm for localizing accessory pathways using only the polarity of the QRS complex].

From 250 consecutive patients who underwent radiofrequency ablation of accessory pathways, we studied 102 patients with successful ablation of a single overt accessory pathway. All patients had manifested preexcitation on a baseline 12 lead electrocardiogram. None of this patients had additional congenital or acquired cardiac abnormalities which could have affected the QRS morphology. A new algorithm for localizing the AP site was developed, based only on the polarity of the QRS complexes in DIII, V1 and V2, without analysis of the delta wave. We could localize the accessory pathway in five sites with 88% of probability of success. This simplify the electrocardiographic analysis of Wolff Parkinson White and improvement the results of radiofrequency ablation.

Adolescent↗

PubMedDate not supplied

[The DDD pacemaker implanted intravenously].

Retrospectively, we studied 66 consecutive patients in whom we implanted an intravenous DDD pacemaker. The indications were: AV block in 52 patients (79%), sick sinus syndrome in 5 patients (7.5%), both AV block and sick sinus syndrome in 4 patients (6%), and other causes in 5 (7.5%). The venous access route was by subclavian punction in 38 cases (57.5%) and by cephalic vein dissection in 28 (42.5%). With a mean follow-up of 16 months, there were complications in 11 patients (17%), in 9 of them, it was necessary a change in pacing mode different to DDD, and was possible to maintain a DDD pacing mode in 2 patients with a minimal reprogramming. The complications were: A) lost of sense and/or atrial capture in 10 patients (3 of them, had also loss of ventricular capture, one had pacemaker-mediated tachycardia, other had diaphragmatic stimulation and other had a severe infection of the pocket), B) atrial fibrillation appeared in another patient. At the implantation time there were significant differences between patients with and without complications on follow-up, the P wave amplitude was 1.86 +/- 0.75 mV in the first group vs. 3.06 +/- 1.52 mV in the latter group, p < 0.005, and the atrial pacing threshold was 1.10 +/- 1.17 microJ in the first group vs. 0.65 +/- 0.66 microJ in the latter group, p < 0.005. We consider that dual chamber stimulation is a well established form of therapy, although, it requires a more laborious implantation and specialized personal for its follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMedDate not supplied

[Radiofrequency ablation in idiopathic ventricular tachycardia originating in the right ventricle].

We present the case of a 10-year-old boy, with structurally normal heart who began two years before admission, with sustained monomorphic ventricular tachycardia with heart rate of 280 bpm and LBBB morphology, AQRS + 60 degrees, with pallor and diaphoresis. The tachycardia was treated with xylocain. He was also treated with propaphenone, verapamil, and amiodarona, in spite of these, he continued with this type of arrhythmia 2 or 3 times a month. We performed an electrophysiologic study which showed ventricular tachycardia originated in the right ventricle infundibulum. We took an endomyocardial biopsy, which was normal. He was scheduled for percutaneous catheter ablation of the tachycardia by radiofrequency energy. During the procedure the ventricular tachycardia appeared spontaneously, we mapped the most early ventricular activation and then in sinus rhythm, this site was pace mapped and resulted in similar pattern of clinical ventricular tachycardia. We identified the site of origin of the ventricular tachycardia in the posterior region of the right ventricle infundibulum, delivering radiofrequency, changing to sinus rhythm. Then we paced the apex of the right ventricle without inducing any form of arrhythmia. He is asymptomatic four months later.

Cardiac Pacing, Artificial↗

PubMedDate not supplied

[Reconstruction of the normal right ventricle outflow tract in the Ross operation].

Now a day there are many surgical procedures that require intervention on the normal right ventricular outflow tract (RVOT) and its reconstruction. We present the surgical anatomy of the pulmonary root in the normal RVOT and its reconstruction in the Ross operation in 13 patients operated on from February 1992 through February 1994. The surgical excision of the pulmonary valve was done and in order to keep right ventricle-pulmonary artery continuity (RV-PA), autologous pericardium tubes with bovine pericardium valve [done at the Instituto Nacional de Cardiología (INC)], were elaborated during the surgical procedure in all patients. The postoperative period and its clinical status was satisfactory in all cases, without transpulmonary gradient or regurgitation. We conclude that is important to know the surgical anatomy of the pulmonary root in order to avoid irreversible damage. In the other hand, it is worthy to know the different choices to reconstruct RVOT and its postoperative clinical course.

Adult↗

PubMedDate not supplied

[Intraoperative circulatory collapse due to a coronary spasm following successful coronary revascularization].

Coronary artery spasm is recognized cause of angina and circulatory collapse during the operative and early postoperative period following cardiopulmonary bypass for coronary artery surgery. We present our experience with hemodynamical collapse during cardiopulmonary bypass weaning, which were refractory to treatment with inotropics such as noradrenaline and adrenalin and vasodilators such as nitroglycerin. The electrocardiographic changes, poor answer to medical treatment following successful cardiopulmonary bypass for coronary artery surgery, good myocardial protection and complete revascularization suggested severe coronary artery spasm. We used sublingual nifedipine, achieving hemodynamical stability and stopping inotropic support and cardiopulmonary bypass. We review the literature about pathophysiologic mechanism and treatment of coronary artery spasm.

Coronary Disease↗