[Percutaneous mitral valvulotomy]. / Valvotomía mitral percutánea.

Percutaneous balloon mitral valvotomy has become the first choice option for the treatment of mitral stenosis. Any patient with the disease is a candidate for the procedure. However there are patient's subgroups which the procedure success will reach a 100% accordingly to a meticulous selection of the cases. Long-term results has been excellent and may be compared with those of surgical closed mitral commissurotomy. We report our long-term follow-up experience of 127 patients followed during a mean of five years in which results have been very favorable.

Comparative trial of stent-like balloon angioplasty versus coronary stenting for acute myocardial infarction.

Primary PTCA has been shown to be superior to any thrombolytic regimen and offers higher reperfusion rates and better coronary flow grades. Its limitations include recurrent ischemia (10%-15%), infarct-related artery reocclusion (5%-10%), angiographic restenosis (35%-50%), and need to perform repeat PTCA or CABG at 6-month follow-up (20%). Thus, the current role of coronary stenting for acute myocardial infarction (AMI) is very promising. From December 1995 through January 1997, 335 patients underwent primary angioplasty during the first 12 hr from symptom onset at our institution. We performed a retrospective study comparing the in-hospital and 6-month follow-up outcome of 61 patients who underwent coronary stenting (stent group) against 61 patients with optimal (residual lesion stenosis < 30%) balloon-only primary angioplasty (stent-like group). Patients were routinely treated with aspirin, and ticlopidine was given only to the stent group. In-hospital major adverse cardiac events (MACE) rate was 11.5% without statistical differences between the groups. Cardiac death rate was similar in both groups (4.9 vs. 6.6%; P = 1.0) and only two (3.3%) patients from the stent group and none from the PTCA group had nonfatal myocardial reinfarction. At 6-month follow-up, the rate of recurrent angina was higher in the stent-like group (30.9 vs. 7.1%; P < 0.001). Multivariate analysis showed that only stenting of the infarct-related artery was a borderline independent predictor for MACE (OR = 0; 95% CI = 0-1; P = 0.057). Primary stenting for AMI reduces the rate of recurrent angina or symptoms and MACE at 6-month follow-up.

[The benefit of a coronary stent in the reduction of major cardiac complications in acute coronary syndromes]. / Beneficio del stent coronario en la reducción de complicaciones cardiacas mayores en síndromes coronarios agudos.

To assess the incidence of in-hospital major adverse cardiac events (MACE), we analyzed 694 procedures in 613 consecutive patients during one year period. Patient population included 550 (79.2%) patients with unstable angina, 43 (6.2%) with stable angina and 101 (14.5%) with acute myocardial infarction. Elective percutaneous transluminal coronary angioplasty (PTCA) was performed in 593 (85.4%) patients, rescue PTCA in 7 (1%), and primary PTCA in 94 (13.5%). Angiographic lesion morphology was as follows: type A 30%; type B 58%; type C 12%. We compared patient population who received stent with PTCA-balloon only. Technical success was 95% and clinical success was achieved in 80% of the cases. Overall mortality was 1% in the stent group and 3% in the conventional PTCA. The incidence of MACE was 4% and 15.1% in the stent and angioplasty balloon groups respectively. We found a dramatic impact on reduction of the incidence of acute complications in the groups with stenting for unstable angina (p = 0.0001) and acute myocardial infarction (p = 0.0001). The major clinical advantage of stenting over balloon angioplasty was a lower need for repeated procedures.

Pericardium-covered stent for septal myocardial ablation in hypertrophic obstructive cardiomyopathy.

This report describes a patient with severe hypertrophic obstructive cardiomyopathy in New York Heart Association functional class III. Complete reduction of left ventricular outflow tract gradient was achieved by the selective occlusion of three target septal arteries with a pericardium-covered stent. The patient's in-hospital course was uneventful and has improved to functional class I.

[The no-reflow phenomenon: its incidence and clinical characteristics in a series of cases]. / Fenómeno de no-reflujo: incidencia y características clínicas en una serie de casos.

The no-reflow phenomenon refers to the inability to reperfuse myocardial tissue despite removal of an occlusion of a coronary artery. No reflow is a complication that may occur after revascularization of patients. This study examined the incidence and, clinical characteristics of no-reflow in a patient population treated with conventional percutaneous transluminal coronary angioplasty at the Instituto Nacional de Cardiología "Ignacio Chávez". We reviewed 204 elective angioplasties and 62 direct angioplasties; 14 patients were included (4 from the first group and 10 from the second group). No-reflow were more frequently in men, the mean age was 56 years and diabetes and smoking were the risk factors more frequently reported. No-reflow was found in left anterior descending coronary artery in 7 patients, the time of reperfusion, in direct angioplasty, was 10.6 hours (mean) and the strategy most frequently used to reestablish normal anterograde flow was intracoronary verapamil. The overall incidence of no-reflow for the two modalities was 5.2% (16.12% for direct angioplasty and 1.9% for elective angioplasty). The current study shows that the no-reflow phenomenon is not uncommon after angioplasty; no-reflow appears higher than the previous reports for both modalities of treatment.

[Coronary stent in acute myocardial infarction]. / Stent coronario en el infarto agudo del miocardio.

UNLABELLED: From December 1995 to March 1997 fifty patients with acute myocardial infarction, had 57 stents implanted. Mean time since the beginning of symptoms to the procedure was 3.7 +/- 2.9 hours. Twenty-four stents were implanted "de novo", 17 for "sub-optimal" results, 5 for threatened closure and eleven for complex dissection. The arteries treated with stent were left anterior descending in 42%, right coronary in 42%, circumflex in 10%, vein grafts in 4%, intermedial branch in 1% and marginal obtuse branch in 1%. Stent used in most of the cases was AVE in 67% followed by Palmaz-Schatz, Wiktor, Crown, Gianturco-Roubin and Wallstent. Before procedure, coronary flow was TIMI 0 in 66% TIMI 1 in 10% and TIMI 2 in 24%. After procedure, TIMI 3 coronary flow was achieved in 92% of the arteries and other four had "no-reflow" phenomenon. Mean stenosis before procedure was 96% +/- 3.1 and after stenting was 1.76% +/- 2.6 with a stent/artery diameter rate of 1.01. Technical success was 100% and clinical success was achieved in 96% of the cases. Two cases were not successfully due to acute thrombotic closure in one patient and in another one because of cardiogenic shock after two days of a technical successful implantation of stent in LAD artery. There were not recurrent ischemic events (CABG, re-infarction or new coronary angioplasty procedure). Other two patients died for non-cardiac events (acute pancreatitis in one and by septic shock in other). At the time of discharge 96% of patients were treated with aspirin and ticlopidine. Major hematoma was evident in only one case. At a mean follow-up time of 5.6 months +/- 4.2 in 45 patients showed that 73% were in functional class I and none of them had re-infarction, death or needed a new revascularization. CONCLUSION: Stent implantation in acute myocardial infarction is feasible and safe procedure with a low rate of ischemic recurrent events.

[Primary angioplasty: comparison of working hours and night]. / Angioplastía primaria: comparación entre los horarios matutino y nocturno.

A prospective, observational, comparative study of 100 patients with acute myocardial infarction and primary angioplasty was performed to establish if there was statistically difference between the lag of time when symptoms begin and the time of the emergency admission to the time of arrival at the catheterization suite during working hours vs the "on call" hours. Patients were allocated in two groups accordingly to morning hours or on call hours. Time of onset of symptoms to the catheterization suite arrival between the two groups was no significantly different. Time from emergency room arrival to catheterization suite arrival was significant different < 0.05, however success rate between groups 86% vs 80% and complications rate were statistically non significant between both groups. We conclude that primary angioplasty is a highly effective method of reperfusion. Even though the time from the emergency room arrival to the catheterization suite arrival was significantly less during day than the on call hours, there is no difference between the success rate and complications incidence in both groups.

[Coronary stents. Results during the hospitalization phase]. / Stent coronario. Resultados en fase hospitalaria.

UNLABELLED: Between October 1991 and August 1996 two-hundred coronary stents were implanted (s) in 166 patients (pts) (1.27 s/pt). One hundred thirty-five lesions "de novo" were approached with stent, 44 because of a sub-optimal result post-angioplasty, 15 for restenosis and 17 for dissection. In thirty-six patients the indication of stenting was stable angina, in 68 unstable angina, in 37 for angina after myocardial infarction, in 11 for asymptomatic ischemia after myocardial infarction and in 14 during an acute myocardial infarction. Mean stenosis before stent implantation in all cases was 85 +/- 15%. Type of lesion in seventy cases was A, in 112 was B and 29 was C. Stents used were AVE in 146 lesions, Palmaz-Schatz in 33, Wiktor in 23, Gianturco-Roubin in 8 and Wallstent in one case. Medical treatment in 140 pts. (84.3%) after stent implantation was only with aspirin and ticlopidine. Technical success in all patients was 98.6% (208/211 pts) and primary success was 94.6% (157-166 pts). Unsuccessful procedures were because of sub-acute occlusion in three patients (1.8%), death in 3 pts. (1.8%) and urgent CABG was necessary in one pt. (0.5%). Major hematoma was a complication in 5 pts (3%). Mean residual stenosis after stent implantation in all cases was 2.2%. CONCLUSION: Stent implantation in our laboratory is a very safe procedure with a high rate of primary success with lowest complications in a great population of unstable angina.

[Clinical experience with AVE Micro Stent. Results of the implantation of 204 stents]. / Experiencia clínica con el "Micro Stent" AVE. Resultados con la implantación de 204 stents.

To assess the efficacy and safety of the AVE Micro Stent, we deployed 204 stents in 144 consecutive patients during a one year period. Indications for stenting were acute closure in 3.4%, dissection in 5.4%, post balloon pTCA restenosis in 3.4%, non-favorable result in 16.7% and de novo in 71.1%. Patient population included 39 (27%) patients with stable angina, 86 (59.7%) with unstable angina, 16 (11.1%) with acute MI and 3 (2.1%) with cardiogenic shock. Angiographic lesion morphology were as follows: type A, 17.7%, type B1, 42.1%; type B2, 16.2%; type C, 24%. Procedural success was obtained in 204 of 205 attempted stents (99.5%) and clinical success was 93.1%. Oral anticoagulation was not routinely used. Enzymatic elevation consistent with myocardial necrosis occurred in 3.2% with Q wave MI in 0.7%. Three patients (2.1%) had bleeding at site of femoral puncture with one requiring transfusion and surgery. Mortality was 0.8% in the angina group, 6.25% in the MI group and one of the 3 patients with cardiogenic shock died and represents the only apparent stent thrombosis as she experienced sudden death one week after successful left main stenting. We conclude that high success rates can be obtained with the AVE Micro Stent due to it's excellent trackability, adequate radio-opacity and relative flexibility.

[Percutaneous mitral valvuloplasty with the Inoue balloon. The initial experience and 3-year clinical follow-up at the Instituto Nacional de Cardiología Ignacio Chávez]. / Valvuloplastía mitral percutánea con balón de Inoue. Experiencia inicial y seguimiento clínico a 3 años en el Instituto Nacional de Cardiología "Ignacio Chávez".

In 113 patients with mitral stenosis a balloon mitral valvuloplasty (VMPB) was performed. There were 97 female and 16 male patients. Mean age was 40 +/- 11 with range of 18 and 70 years. 95 patients had sinus rhythm and 18 were on atrial fibrillation. Previous mitral commissurotomy was reported in 13 patients and 5 were pregnant at the moment of the procedure. Patients were carefully selected using both clinical and echocardiographic studies as well as the Wilkins score (SW). Transesophageal echocardiography (ETE) was performed when transthoracic echocardiography was not satisfactory. After right and left catheterization, VMPB was performed. In 106 patients (93.8%) a significant increase of the area mitral valve (AVM) was obtained. Echocardiographic results showed an AVM increase from 0.95 +/- 0.19 to 1.61 +/- 0.34 cm2 (p < 0.0001). Mean mitral gradient (GTM) decreased from 16.18 +/- 4.69 to 9.14 +/- 3.2 mmHg (p < 0.0001). Functional class improved in all patients in the long term. As complications there was severe mitral regurgitation (IM) reported in 6 patients who subsequently underwent mitral valve exchange, 2 of then died during surgery (one of them by bleeding and the other by non reparable rags on the atrium). A patient had cerebrovascular event (EVC) one week after the VMPB. In 3 of them non-significant interatrial communication (CIA) was produced. One patient died two months after the procedure due to bacterial endocarditis (EBSA). VMPB can be considered as a safe and effective treatment to patients with mitral stenosis.

[Coronary angioplasty with the Monorail system via 6 French diagnostic catheters]. / Angioplastía coronaria con sistema "Monorail" a través de catéteres diagnósticos 6 French.

We studied the use of "Monorail" system with Express (Scimed) balloon catheters for coronary angioplasty through 6 French (F) "high-flow" diagnostic catheters (Novoste, USCI). Prospectively, from July 1992 to January 1993, angioplasty of 31 lesions in 24 patients was attempted (1.3 lesions/procedure). Twenty procedures were of a single lesion and four were multi-vessel angioplasty. Fourteen lesions were in the left anterior descending or in its branches, 10 in the left circumflex or in its branches, 6 in the right coronary artery, and one in the distal anastomosis of an internal mammary artery graft. Thirteen lesions (42%) were type A, 17 (55%) type B and one (3%) type C. Balloon sizes varied between 2.0 and 3.5 mm. Twenty-nine lesions could be successfully dilated (93.5%); two cases were unsuccessful due to an acute occlusion in one and residual stenosis of more than 50% in the other. For only one case, another balloon catheter different from the "Monorail" system was necessary to complete a multi-vessel angioplasty. Coronary visualization and manipulation of the balloon through the tip of the diagnostic catheter were satisfactory in all cases, except with the 3.5 mm balloon catheter. Coronary angioplasty with "Monorail" system balloon catheters through 6 F "high-flow" diagnostic catheters is feasible and provides a high success rate in simple and moderately complex selected lesions, including multivessel angioplasty with advantages of smaller artery punction and the feasibility of performing coronary angioplasty with the same catheter used for diagnostic angiography.

[Coronary angioplasty in patients not accepted for surgical treatment. The initial experience of the Ignacio Chávez Instituto Nacional de Cardiología]. / Angioplastía coronaria en pacientes no aceptados para tratamiento quirurgico. Experiencia inicial del Instituto Nacional de Cardiología "Ignacio Chávez".

Coronary angioplasty has shown its efficacy in "high-risk" patients for surgical treatment (severe left ventricular failure, serious pulmonary or systemic disease). We studied a subgroup with multivessel coronary heart disease treated with coronary angioplasty because they were no candidates for surgery due to unsuitable coronary anatomy. Revascularization rate was determined in each patient as revascularization percentage obtained, compared with all the technically suitable lesions for coronary angioplasty. Ten patients (mean age 63 years) were studied, eight of them had unstable angina. Overall, 44 lesions were considered technically suitable for angioplasty and thirty-five could be dilated, technical success rate was 88% (31/35 lesions) and revascularization rate was 71% (31/44 lesions). Primary success rate was achieved in nine patients. Clinical follow-up varied from two to thirteen months (mean 7.8 months); eight patients have remained asymptomatic (class I of NYHA), another patient had stable angina and the other one had sudden death six months after the procedure. In conclusion, we demonstrated a high success rate in a short and long term with coronary angioplasty in a subgroup of patients with multivascular coronary heart disease that had been rejected for surgery due to unsuitable coronary anatomy.

[The primary outcome in transluminal coronary angioplasty: the recent experience of the Instituto Nacional de Cardiología (1991-1992)]. / Exito primario en angioplastía coronaria transluminal: experiencia reciente del Instituto Nacional de Cardiología (1991-1992).

Percutaneous balloon coronary angioplasty had a slow start in Mexico, and until recently only a relatively small number of procedures have been performed. Since March 1991, the Instituto Nacional de Cardiología has state-of-the-art fluoroscopic imaging and easy access to a variety of balloon coronary angioplasty catheters and accessories. Under these conditions, an increasing number of PTCAs have been performed (221 procedures in an initial 15 month period). The primary results of PTCA in this patient population is presented as a reference source for results of PTCA in our population. Indication for PTCA was stable angina in 31%, unstable angina in 64% and AMI in 5%. Forty-two percent of the procedures were for multivessel PTCA, with a total of 355 lesions approached (1.6 segments per patient). There were 34% type A, 51% type B and 15% type C lesions. Mean percent stenosis was reduced from 81% to 29% (p < 0.001). There was a 94% success rate in type A lesions, 89% in type B and 77% in type C lesions. Six patients required urgent CABG (2.7%), thirteen had a myocardial infarction (5.9%) and mortality was 1.35% (including one patient with cardiogenic shock who had a noncomplicated failure and had a late in-hospital death). We conclude that with adequate support and equipment, angioplasty results compare favorably to those reported by more experienced groups in developed nations. Also, the necessary number of procedures for the maintenance of competence in PTCA can be done in our country.

[Detection of early occlusion of aortocoronary by-passes. Usefulness of a non-angiographic method]. / Detección de la oclusión temprana de puentes aortocoronarios. Utilidad de un método no angiográfico.

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.

[The usefulness of transesophageal echocardiography during percutaneous balloon mitral valvulotomy]. / Utilidad del ecocardiograma transesofágico durante la valvulotomía mitral percutánea con balón.

The purpose of this study is to report the experience at Instituto de Cardiología de México with transesophageal echocardiography during percutaneous mitral valvulotomy and to compare its utility with transthoracic echocardiography. Sixteen patients with isolated or predominant mitral stenosis were examined and underwent percutaneous mitral valvulotomy with a single balloon catheter (Inoue [correction of Ionue] technique). Transthoracic echocardiography was done in all cases previous to the procedure. The procedure orientation was done with transesophageal in thirteen patients and with. Transthoracic echocardiography in the other three. The results were successful in all cases. Transesophageal echocardiography was more useful in the initial evaluation in patients with poor transthoracic windows, in those with clinical and/or transthoracic evidence of atrial thrombosis, as well as in procedure orientation, spontaneous contrast detection, mitral regurgitation and atrial septal defect evaluation after the procedure. Transesophageal echocardiography is superior to transthoracic technique in procedure orientation, early evaluation of results and potential complications. However, its practical utility is limited and its routine use is not recommended.

[Changes in auriculoventricular conduction due to the effect of ethanol]. / Modificaciones de la conducción auriculoventricular por efecto de etanol.

Transcoronary ablation of atrioventricular conduction by dehydrated alcohol was attempted in one patient with refractory ectopic atrial tachycardia. Ethanol (1.5 ml) was delivered after selective catheterization of the atrioventricular nodal artery in a patient in whom the artery could be identified by cineangiography. The mean creatine kinase (MB fraction) at four hour to six hour after ablation was 40 U. No electrocardiographic QRS changes was seen. The procedure was successful. The patient is asymptomatic 3 months after procedure. Transcoronary alcohol ablation of atrioventricular conduction should be considered in patients in whom electrical techniques have been unsuccessful.

[Percutaneous mitral commissurotomy with Inoue balloon. Short-term results. Initial experience at the Ignacio Chavez National Institute of Cardiology]. / Comisurotomia mitral percutanea con el balon de Inoue. Resultados a corto plazo. Experiencia inicial del Instituto Nacional de Cardiologia "Ignacio Chavez".

Percutaneous transvenous mitral commissurotomy (PTMC) using balloon catheters has emerged as an alternative to surgery for patients with mitral stenosis. This report details our recent experience of PTMC with the Inoue balloon in 20 consecutive patients with mitral stenosis from april 2 to july 27, 1991. Mean age was 35.6 +/- 9.5 years. Mitral valve area increased form 1.04 +/- 0.3 to 2.32 +/- 0.5 cm2 (p less than 0.0001). Mitral valve gradient decreased from 19.2 +/- 8.8 to 6.6 +/- 2.3 mmHg. (p less than 0.0001). Two patients developed mitral regurgitation greater than 2+/4 after the procedure. In none the residual left to right shunt was greater than 1.2L. There was no mortality. We conclude that in selected patients, excellent results are obtained PMTC with the Inoue balloon. Complications are minimal.

[Use of technetium 99m radio-angiocardiography in the identification of myxoma of the right atrium. Presentation of 2 cases]. / Uso de la radioangiocardiografía con tecnesio-99m en la identificación del mixoma de la aurícula derecha. Presentación de dos casos.

A right atrial myxoma was identified in two patients with radio-angiocardiography-99m Tc. Tumor is identified as a persistent photon-deficient region in both first-pass and equilibrium images. In addition there is an abnormal accumulation and sluggish disappearance of the radionuclide from the right atrium. Even though sensitivity of the procedure should be confirmed, it is a helpful non-invasive technique of great value in the diagnosis oF right atrial tumors.

In vivo mechanical behavior of canine pericardium.

We examined the in vivo mechanical behavior of the pericardium by measuring simultaneous atrial and intrapericardial pressures and mutually orthogonal, circumferential, and longitudinally oriented pericardial segment lengths (ultrasonic gauges) in 10 open-chest dogs. Venous return was varied by a combination of caval occlusion followed by volume loading. Up to a mean left atrial pressure of 25 mmHg, the pericardium lengthened virtually exclusively in the circumferential direction (n = 9). Thus, at an intrapericardial pressure of 6.0 +/- 1.0 (+/- SD) mmHg, circumferential strain (normalized to length at pericardial pressure 0 mmHg) was 0.30 +/- 0.28, whereas longitudinal strain was 0.02 +/- 0.06 (P less than 0.05). In five of these dogs, alteration of external pericardial loading by severing the pericardial diaphragmatic attachments did not change the difference between circumferential and longitudinal strain, and in two the same directional strain difference was observed during production of cardia tamponade. In three additional dogs the square of the circumferential segment length was closely correlated with the directly measured intrapericardial volume when saline was infused into the pericardial space in an in situ, arrested heart preparation. Our results indicate that there is marked directional variability in lengthening of the pericardium when the volume of its contents is altered in vivo. This phenomenon is probably the result of complex interactions between the properties of the pericardial tissue and the influence of its internal and external loads.