[Electrocardiographic data suggesting anteroseptal myocardial infarction, in presence of infarction of the left ventricle]. / Datos electrocardiográficos sugestivos de infarto del miocardio anteroseptal, en presencia de infarto del ventrículo derecho.

We present a case of right ventricular myocardial infarction, secondary to postangioplasty occlusion of ventricular ramus of the right coronary artery, that developed electrocardiographic changes suggestive of septal myocardial infarction, this diagnosis was eliminated through angiographic study. We conclude that the carefully analysis of the electrocardiographic changes in ST segment in V1 to V4 can guide to the diagnosis of right ventricular myocardial infarction. For that reason we recommend the routinary register of the right electrocardiographic derivations as V3R and V4R, and left derivations V7 and V8, that is, the thoracic circle, in all patients with acute myocardial infarction regardless its location.

[Peripheral and coronary angioscopy: its correlation with endovascular procedures]. / Angioscopía periférica y coronaria: su correlación en procedimientos endovasculares.

The efficacy of any method of transluminal angioplasty has been evaluated with angiography, this can show the major anatomic results. Angioscopy can detect by direct observation, the induced changes in the vessel wall morphology after the recanalization method. We studied 5 coronary arteries and 9 peripheral arteries with total occlusion in 7, and the other 7 with more than 75% of obstruction. All of them were evaluated with angiography and angioscopy, before and after the transluminal angioplasty. Eleven of the arteries were treated by transluminal ultrasound angioplasty, we obtained recanalization in 90% of them, in 6 (55%) of this we found angioscopic evidence of dissection in variable degrees. Two cases were treated only with balloon angioplasty, and the angioscopy image was of dissection too. In the only case of laser angioplasty we observed dark brown coloration in the treated lesion suggesting carbonization changes. The initial angiography analysis did not suggest the presence of complication of the atheroma plaque. However in 21% of the cases the angioscopy inspection demonstrated and hemorrhagic dye of the endothelium, and thrombosis in situ in 29%. We no found correlation in angiography and angioscopy aspect in 25% of the cases. Some of the endothelial alterations that can not be detectable by angiography, can be demonstrated by angioscopy, this changes could improve the appreciation of any recanalization method results, that could suggest its possible immediate and late complications.

[Doppler echocardiography assessment of tricuspid valve prosthesis with normal function and with dysfunction due to obstruction]. / Evaluación mediante ecocardiografía Doppler de las prótesis valvulares tricuspídeas con función normal y con disfunción por obstrucción.

UNLABELLED: In order to know the normal ranges of the maximum velocity and the pressure half-time between normal functioning tricuspid prostheses and malfunctioning tricuspid prostheses due to obstruction, we studied 25 patients with tricuspid prostheses (11 mechanical and 14 biological); they were divided in 2 groups: group I: 14 patients without clinical evidence of malfunction and; group II: 11 patients with malfunction due to obstruction confirmed by catheterization, surgery and/or necropsy. The peak gradient was estimated by the modified Bernoulli equation and the prosthetic valve area by the pressure halftime method. RESULTS: the mean peak velocity in group I was 147 +/- 18 cm/sec versus 165 +/- 16 cm/sec (p NS) in group II. The mean pressure half-time in group I was 124 +/- 20 msec versus 355 +/- 48 msec (p less than 0.001) in group II. CONCLUSIONS: 1. A pressure half-time greater than 200 msec is very suggestive of malfunction due to obstruction (p less than 0.001). 2. There are normo-functioning tricuspid prostheses with prolonged pressure half-time, and the values that divides these groups from those with malfunction is small: 199 and 244 msec, that is why we suggest that every patient has to have his her own echocardiographic control in the immediate postoperative period.

Percutaneous transluminal ultrasonic angioplasty: preliminary clinical report of ultrasound plaque ablation in totally occluded peripheral arteries.

Peripheral arterial obstructive disease has been treated with ultrasound ablation. Thirty two patients (pts), mean age 67 +/- 10 years underwent angiosonoplasty, with a prototype ultrasonic system, due to severe claudication (31%), rest pain (44%), rest pain and ulceration (25%). Angiosonoplasty was successful in 26/32 (81%) stenoses, (1/2 iliac, 9/2 femorals, 11/12 popliteal, 5/6 tibial). Angiography before and after angiosonoplasty confirmed that the lesions were successfully opened, (81%, p less than 0.05). A mean of 3 +/- 2 passes were required to adequately remove sufficient plaque. Balloon angioplasty was used in combination with angiosonoplasty in 11/32 (34%) occluded vessels. Complications included groin hematoma in 4 pts (12%) and vascular spasm in two patients (6%). Within 24 hours, 27/32 (94%) pts were discharged clinically improved. Reocclusion occurred in 4 pts (12%) immediately after the procedure. Ankle brachial indices significantly increased from 0.52 +/- 0.10 before to 0.70 +/- 0.12 after (p less than 0.05). In conclusion, the use of ultrasound energy to ablate atherosclerotic plaque would appear safe, and has shown no restenosis and a low incidence of complications over a six month period.

[In vitro effects of argon laser radiation the human healthy and atherosclerotic aorta]. / Efectos in vitro de la radiación del laser de argón en aorta sana y aterosclerosa.

Argon laser exposures in vitro were done on human aortas. The laser energy applied on a fresh aorta section (A) was from 100mw to 1000mw. A second aorta section (B), formalin fixed, was irradiated under saline solution by a fiberoptic system. Laser energy was from 400mw to 720mw. The time exposures were all different in both sections. A and B histologic findings of thermal damage were similar Three zones of tissue injury were observed: I) crater because of tissue vaporization; II) coagulative necrosis surrounding it; and III) multiple vacuoles in the adjacent tissue produced by acoustic or shock injury. Tissue damage was related directly with total energy delivered: less than or equal to 500mw showed inner vascular wall necrosis, and at greater than or equal to 720mw it was perforated. Atherosclerotic tissue was more resistant to laser thermal injury than normal tissue. We could not find time relation with thermal damage. This preliminary information is an early step for the possible use of Argon laser on cardiovascular area.

[Simplified method for the early detection of post potentials in patients with acute myocardial infarct]. / Método simplificado para la detección temprana de postpotenciales en el paciente con infarto agudo del miocardio.

The risk of suddenly presenting ventricular tachyarrhythmias or death was analyzed in a prospective way in 71 patients with acute myocardial infarction and in 21 patients without any apparent cardiopathy. The average surface signal was measured when the patient was admitted in the hospital and on the following days of the acute phase of the infarction. Holter 24 hours monitoring and determination of the ejection fraction with radionuclide angiocardiography were also performed. Patients were divided into 4 groups, depending on the existence of arrhythmias and if late electric activity was recorded or not. Fifty-five patients (group I), presented an abnormal signal analysis (voltage in the 40 msec of the QRS period higher than 20 microvolts), and ventricular arrhythmias. Group II was formed by 8 patients who presented arrhythmogenic activity but did not present late electric activity. Group III was formed by 6 patients who did not present arrhythmias but presented late electric activity. Twenty-three patients who did not present late electric activity or ventricular arrhythmias formed group IV. Late electric activity that was registered at 41 +/- 1 msec with a QRS complex lasting 115 +/- 4 msec and with a voltage lower than 20 microvolts in group I showed meaningful differences with the other groups: Group II: (24 +/- 5 msec, QRS 111 +/- 4 msec, P less than 0.001); Group III: (41 +/- 2 msec, QRS 109 +/- 5 msec, P less than 0.01); Group IV: (26 +/- 5 msec, QRS 80 +/- 7 msec, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Transluminal coronary angioplasty using ultrasound]. / Angioplastía coronaria transluminal por ultrasonido.

The application of ultrasonic energy for ablation of atherosclerotic plaques was studied. This study was performed in 92 segments obtained from human coronary arteries which belonged to eleven hearts obtained from patients who have died from acute myocardial infarction. An ultrasound generating system (Cavitron 600) was used, and an ultrasonic probe wire (P-150 Endosonic), was attached to it. A stainless steel wire (0.36 mm in width and 145 cm length), was fixed to this probe. Sonic pulsed stimulations 20 sec long and 25 kHz in frequency were performed. The sound transmitting characteristics of the angioplasty guide wire were studied, as well as the ultrasound effects upon atherosclerotic plaques, blood elements, coagulation, and it's lysis effects upon recently formed clots. The anatomic pieces were filmed in cineangiocoronary graphy in two planes, anterior right oblique an anterior left oblique, to be studied later under light microscopy. The results were as following: in the 100% obstructions, a 41% recanalization was obtained; in the 95% obstructions, a 79%, in the 75% obstructions, a 37%. We did not work in the 50% or less obstructions. Under the procedure, no artery suffered perforations. Under Light microscopy, a plaque fragmentation was observed in 24% of the cases; rupture and fragmentation, in 14%, cavitations in 10%; ondulations in 9%; plaque rupture and thermic lesion in 8%; 22% did not present changes. The collected detritus had 110 +/- microns diameter. Erythrocytes exposed to 30 or 60 sec of ultrasound were found to present crenocytosis, central cavitation, hypochromia, and poikilocytosis; these ones exposed less than 22 sec did not show changes. The fibrinogen levels after the application of ultrasound were 19% lower. Coagulation time did not change with exposure 20 sec long at 20 kHs. The angioplasty guide wires attenuation coefficients were: with the guide wire outside the Miller's catheter, 44%; and with the guide wires inside, 65%. Coronary transluminal angiosonoplasty is a new interventionist technic designed to remodel an obstructive lesion of the coronary arteries, in order to diminish or nullify the obstruction. It's clinic use in the acute myocardial infarction, as a mechanical method to achieve clot's lysis, could be an alternative or a co-helper therapeutics to thrombolysis.

[Electric cardioversion in the emergency service. Experience in 1000 cases]. / Cardioversión eléctrica en el servicio de urgencias. Experiencia de 1000 casos.

We describe our experience with 1000 electric cardioversions performed at the emergency ward in the Hospital of Cardiology y Neumology, National Medical Center I.M.S.S. The objectives are: 1. Report our experience. 2. Investigate if digitalis treatment should be discontinued before the procedure. 3. Determine if all patients should be on anticoagulant therapy for elective cardioversion. 4. Indicate the optimal anesthetic drug with minimal side effects. A therapeutic procedure was performed in 73% of our cases and an elective one in the remaining 27%. Patients were grouped as ischemic heart disease 26%, rheumatic heart disease 24%, chronic obstructive pulmonary disease 14%, systemic hypertensive heart disease 13%, without clinical heart disease 6%, preexcitation syndrome 6%, adult congenital heart disease 4%, with implanted pacemaker 2%, pregnancy 2% and diverse myocardial diseases 2%. As a cardiac arrhythmias atrial fibrillation was the main cause 45%. Atrial flutter represented 25%, atrial paroxysmal tachycardia was 21% and ventricular tachycardia 9%. A cardioversion was performed in 43% of patients under digitalis treatment at therapeutic levels, without complications. Atrial flutter reverted to sinus rhythm in 98% of the procedures, and atrial fibrillation in 97%. Elective cardioversion in patients with atrial fibrillation was achieved with energies of 200 joules in 82% of the procedures (P less than 0.001) and in atrial flutter with 100 joules in 89% of the cases (P less than 0.001). The most frequent complications were atrial and junctional premature beats in 41% of the cases. We consider this procedure a safe one, effective at the energy levels described, with no need for discontinuation of digitalis therapy, with no mandatory previous anticoagulant therapy, and with no contraindications on pregnancy or implanted pacemakers.