Resultados a largo plazo de la valvuloplastía mitral con balón / Long term results of mitral balloon valvuloplasty

Background: Mitral balloon valvuloplasty (MBV) is the therapy of choice for the treatment of symptomatic mitral stenosis with suitable anatomy. Although its short and mid-term results are favorable, there is a paucity of information about long-term follow-up. Aim: To assess the late results of MBV. Material and Methods: A cohort of 225 patients aged 8 to 20 years who were subjected to a MBV from 1989 to 2001, was studied. All variables at the time of the procedure, short and long-term results and major events during follow-up (new mitral intervention and mortality) were recorded. Uni and multivariate analysis were used to assess prognosis. Results: The mean follow-up lapse was 13.5 years (range 8 to 20 years). During this period, 88 patients (39.1%) remained event-free and in acceptable functional capacity. Eight percent died, 8% required a second MBV and 43.5% required a surgical mitral valve replacement. A post-procedural area equal or greater to 1.9 cm² was associated with a greater likelihood of free-event survival (log rank test: p = 0.02/Cox proportional regression model: coefficient 0.54, p = 0.04). Conclusions: MBV is effective, although there is a high chance of new interventions in the long-term follow-up. A larger post-procedure mitral area is associated with a better prognosis.

[Long term results of mitral balloon valvuloplasty]. / Resultados a largo plazo de la valvuloplastía mitral con balón.

BACKGROUND: Mitral balloon valvuloplasty (MBV) is the therapy of choice for the treatment of symptomatic mitral stenosis with suitable anatomy. Although its short and mid-term results are favorable, there is a paucity of information about long-term follow-up. AIM: To assess the late results of MBV. MATERIAL AND METHODS: A cohort of 225 patients aged 8 to 20 years who were subjected to a MBV from 1989 to 2001, was studied. All variables at the time of the procedure, short and long-term results and major events during follow-up (new mitral intervention and mortality) were recorded. Uni and multivariate analysis were used to assess prognosis. RESULTS: The mean follow-up lapse was 13.5 years (range 8 to 20 years). During this period, 88 patients (39.1%) remained event-free and in acceptable functional capacity. Eight percent died, 8% required a second MBV and 43.5% required a surgical mitral valve replacement. A post-procedural area equal or greater to 1.9 cm² was associated with a greater likelihood of free-event survival (log rank test: p = 0.02/Cox proportional regression model: coefficient 0.54, p = 0.04). CONCLUSIONS: MBV is effective, although there is a high chance of new interventions in the long-term follow-up. A larger post-procedure mitral area is associated with a better prognosis.

Relative bioavailability study with two oral formulations of topiramate using a validated UPLC-MS/MS method.

Changes in bioavailability of anticonvulsant drugs such as topiramate may cause loss of or worsened seizure control. Thus, the purpose of this study was to evaluate, in a double-blind crossover design, the bioavailability between two oral formulations of topiramate in healthy volunteers after a single dose. The protocol, approved by the Institutional Committee of Ethics, consisted of administration of 1 tablet of 100 mg of topiramate of each formulation (Toprel and Topamax), to 20 healthy volunteers after a 12 h overnight fast, using an open, two-period, randomized, crossover and double-blind design. Thus, the plasma concentrations (Cp) of topiramate were measured at predetermined intervals of time, from 0 to 24 h, using a validated UPLC-MS/MS method. Based on plasma concentration-time profiles we obtained the following pharmacokinetic parameters: AUC(0-inf) 63,418.31 +/- 22,141.69 and 67,094.70 +/- 22,487.2 ngh/ml; AUC0-24: 30,421.02 +/- 9,964.0 and 30,489.35 +/- 9,407.17, ng x h/ml; tmax: 2.77 +/- 1.76 and 1.95 +/- 1.89 h; C(max): 2,143.33 +/- 724.26 and 2,262.51 +/- 751.12 ng/ml, for A (Toprel) and B (Topamax), respectively. All these differences were not statically significant with 90% confidence interval. The test of bioequivalence showed that Cmax, AUC(0-24) and AUC(0-inf) parameters are found within the range of 0.8 - 1.25 recommended by the FDA with a probability of bioequivalence of 100%. In accordance with these results, we can conclude that Toprel 100 mg, A (Test), is a bioequivalent generic and interchangeable with Topamax 100 mg, B (Reference).

Utilidad del cierre del foramen oval permeable en pacientes con AVE criptogénico / Closure of patent foramen ovale in patients with cryptogenic stroke

Antecedentes: El foramen oval permeable (FOP) es un hallazgo frecuente en pacientes con accidente vascular encefálico criptogénico (AVEC), y se discute la utilidad de su cierre percutáneo (CP). Objetivo: Evaluar el riesgo de recurrencia de eventos neurológicos en pacientes con AVEC y FOP, y compararlos entre aquellos tratados médicamente y los sometidos a CP. Métodos: Entre los 106 pacientes admitidos por AVEC y FOP, en el período 2003 a 2006, determinamos la aparición de nuevos eventos neurológicos isquémicos (NEN), y estudiamos sus factores determinantes y comparamos los que se sometieron a CP versus lo que continuaron con tratamiento médico, según criterio del tratante. Se consignaron las características clínicas y de la antomía del FOP en el ecocardiograma Los NEN se confirmaron por examen neurológico y/o neuro-imágenes. Para el análisis de los datos se utilizó chi-cuadrado y regresión logística.Resultados: Entre los 106 pacientes evaluados, 87 siguieron tratamiento médico y 19 CP. Los pacientes sometidos a CP presentaban mayor asociación de FOP con aneurisma del septum interauricular (ASI) (57,9% versus 35,6%, p=0,05). El seguimiento fue de 27 +/-13 meses. En este período se demostró un 12,6% de nuevo evento neurológico entre los tratados médicamente, mientras que ninguno lo presentó entre los sometidos al CP (NS). El único predictor independiente para NEN fue el ASI asociado con FOP; OR: 8,45 (1,56-60,46). Conclusiones: De acuerdo a nuestros resultados, los pacientes con AVEC y FOP tienen alto riesgo de recurrencia cuando el FOP se asocia a ASI y aparentemente se benefician con CP.

Background: Patent Foramen Ovale (PFO) is a frequent finding in patients with cryptogenic stroke (CS). Theeffect of closing the PFO in this setting is debated. Aim: to evaluate de risk of stroke recurrence in patients with CS and PFO; to compare this risk in patients followed under medical treatment with those undergoing percutaneous closure of PFO. Methods: From 2003 to 2006, 106 patients were admitted with a CS and the presence of PFO was documented by echocardiography. New ischemic strokes and risk factors were compared between those who weresubmitted to percutaneous closure of PFO and those treated in a conventional way. The decision to close thePFO was taken by the physician in charge. Clinical findings and echocardiographic characteristics of thePFO were recorded. New ischemic events were diagnosed by neurologic assessment and/or imaging techniques. Data was analyzed by chi square testing and logistic regression. Results: 87 patients were followed under medical treatment and 19 had closure of the PFO. The latter group had a greater incidence of atrial septal aneurysm (57.9% vs. 35.6%, p=0.05). The mean follow up was 27 +/- 13 months.New ischemic stroke occurred in 12.6% in the medically treated group while none was observed in the PFO closure group (NS). The sole independent predictor of new stroke was the presence of atrial septal aneurysm (OR: 8.45, 95% C.I. 1.56 - 60.46) Conclusion: Patients with CS and PFO are at considerable risk of developing new strokes, especially those with concomitant atrial septal aneurysm. Closure of PFO was apparently useful to prevent this risk.

Coronariografía no invasiva mediante tomografía axial computada multicorte / 16 detector computed tomagraphy for coronary angiography

Antecedentes: La tomografía axial computada de 16 detectores de las arterias coronarias (TAC Coronario) ha emergido recientemente como una alternativa diagnóstica a la coronariografía invasiva (CI). Objetivo: Estudiar la exactitud del TAC coronario de 16 detectores para pesquisar la presencia o ausencia de estenosis coronaria en distintos tipos de pacientes, mediante su comparación con la CI. Métodos: A un total de 55 pacientes (46 hombres, 9 mujeres, promedio 57 +/-12 años) en quienes se realizó una CI electiva, se les realizó un TAC coronario. Se analizó específicamente la presencia de lesiones 50 por ciento y se compararon estos resultados con los obtenidos mediante la CI cuantitativa. Resultados: Cincuenta pacientes requirieron beta bloqueo, obteniéndose una FC promedio de 57 lpm. En los segmentos principales se objetivaron 61 lesiones significativas por CI, de las cuales 52 (85,2 por ciento) fueron correctamente detectadas por el TAC coronario. La sensibilidad, especificidad, LH(+) y LH(-) del examen fueron 85 por ciento, 97 por ciento, 33 y 0.15, respectivamente. La presencia o ausencia de enfermedad coronaria significativa fue correctamente diagnosticada en 50 de los 55 pacientes (91 por ciento). Conclusión: El TAC coronario de 16 detectores es un examen sensible y específico para el diagnóstico de estenosis significativas de los segmentos principales del árbol coronario.

Background: Invasive coronary arteriography (ICA) is the gold standard to assess coronary artery stenosis. Sixteen detector computed tomography (Coronary CT) has recently been introduced as a less invasive diagnostic alternative. Aim: To assess the reliability of Coronary CT in detecting coronary stenosis among different types of patients by comparing the results with those obtained by ICA. Methods: 55 patients (age 57+/-12 years, 46 males) who underwent ICA had also a coronary CT. Beta blockade was used to obtain a heart rate < 65 beats per min. The presence of significant stenosis (•'3d50 percent of luminal diameter measured by quantitative angiography) was compared between methods.Results: Adequate coronary images were obtained in 53 of 55 patients with coronary CT; a total of 715 coronary segments were available for analysis. Fifty patients required beta blockade and the mean heart rate was 57 beats per min. Fifty-two out of 61 main segment stenosis were detected by coronary CT (85.2 percent). Sensitivity, specificity, LH+ and LH- of coronary CT were 85 percent, 97 percent, 33 and 0.15, respectively. The presence or absence of significant lesions was correctly diagnosed in 50 of the 55 patients (91 percent). Conclusion: 16 detector coronary CT is a sensitive and specific method to diagnose main segment significant coronary stenosis.

Enfermedad periodontal en pacientes con síndrome coronario agudo / Periodontal disease among patients with acute coronary syndrome

Background: Epidemiological studies suggest an association between periodontal disease and coronary heart disease. It is possible that periodontal disease may contribute to plaque destabilization in patients with acute coronary syndrome. Aim: To assess the association between severity of periodontal disease, the number of acute plaques and extension of coronary artery disease in patients with acute coronary syndrome. Patients and methods: The severity of periodontal disease was assessed by skilled independent observers in patients with acute coronary syndrome subjected to coronary angiography. The periodental disease was classified as mild or severe. Acute plaques were defined on angiography as those with thrombi, ulcers or flow alterations. The extension of coronary disease was analyzed using the Sullivan score. Results: Forty three patients (35 males) aged 41 to 83 years, were studied. Mild and severe periodontal disease was present in 18 (42percent) and 25 (58percent) patients respectively. Seventy six percent of those with severe disease had two or more acute plaques, compared with 17percent of those with mild disease (p<0.001). Median Sullivan score was 80.6 and 57.2 in patients with severe or mild periodontal disease respectively (p=0.001). Conclusions: Severe periodontal disease was associated with a higher number of acute coronary plasques and a higher extension of coronary artery disease, in patients with acute coronary syndromes.

Práctica contemporánea de la angioplastia coronaria en Chile: informe final del Registro Nacional de Angioplastia Coronaria (RENAC) 2001-2002 / Final report of the Chilean National Coronary Angioplasty Registry (RENAC)

Background:Coronary angioplasty was introduced in Chile in 1982, but only after the introduction of stents it became commonplace. However, the results of this procedure at the national level remain largely unknown. Aim: To assess the results and characteristics of coronary angioplasty and develop a national registry in Chile (RENAC). Patients and Methods: All centers performing angioplasty were invited to contribute prospectively with the clinical, angiographic, procedural characteristics and results of all consecutive coronary angioplasty procedures attempted between June 2001 and October 2002. Results: In 10 centers, 1768 lesions were treated in 1484 procedures (22.98 percent in women). Mean age was 60.8±11.3 years old. Diabetes was found in 21.8 percent, hypertension in 60.2 percent, dyslipidemia in 52.0 percent, active smoking in 40.0 percent, renal failure in 6.2 percent. Myocardial infarction was recent in 28.4 percent and acute in 19.7 percent. Forty eight percent of patients had unstable angina and 15.5 percent had stable angina. Fifty three percent of patients had single vessel disease and 71 percent, normal left ventricular eyection fraction. One vessel was treated in 90.6 percent of patients and 81.7 percent of lesions were treated with stents, 17.9 percent only with baloon and in 0.4 percent with atherectomy. Angiographic success was obtained in 95.2 percent. Clinical success was obtained in 92.2 percent, and 95.1 percent in patients without acute myocardial infarction. Overall inhospital death was 2.2 percent. In patients without myocardial infarction, the figure was 1.1 percent. Conclusions: Coronary angioplasty in Chile is performed mostly for the treatment of acute coronary syndromes. Stents are the most frequently used devices. The high success, low mortality and complications observed are comparable to North American registries (Rev Méd Chile 2004; 132: 913-22).

Características del electrograma local en fulguraciones exitosas de haces paraespecíficos / Characteristics of the local electrogram in successfuly fulgurations of paraspecific bundles

La ablación por radiofrecuencia de haces paraespecíficos es un aterapia muye efectiva para el tratamiento de las taquicardías paroxíticas supraventriculares. Con el objeto de evaluar la utilidad del electrograma local en la identificación del sitio correcto para efecturar la ablación por radiofrecuencia, se analizaron las características de éstos en 20 pacientes con haces paraespecíficos fulgurados exitosamente. 16 pacientes tenían un haz paraespecífico izquierdo (10 ocultos), 2, haz paraespecífico anteroseptal y 1, un haz paraespecífico lateral derecho. En 15 pacientes la fulguración se realizó durante taquicardia paroxítica supraventricular y en 5, durante ritmo sinusal. En los 20 electrogramas analizados, el hallazgo más frecuente fue el de complejos fusionados. Se registró un probable electrograma de Kent en 3 pacientes fulgurados en taquicardia y en 4 pacientes fulgurados en ritmo sinusal. Pensamos que ninguna de las características del electrograma local tiene un valor predictivo alto para precisar el sitio de la fulguración exitosa

Ablación por radiofrecuencia de haces auriculoventriculares anómalos en niños con taquicardia paroxística supraventricular / Radiofrequency ablation of abnormal atrioventricular bundle in children with paroxysmal supraventricular tachycardia

En 21 pacientes (edad promedio 9,7, márgenes 4 a 16 años) con taquicardias paroxísticas supraventriculares por haces paraespecíficos, se realizaron estudios eslectrofisiológicos y ablación de los haces por radiofrecuencia. Dos pacientes tenían malformaciones congénitas del corazón. La ablación se consiguió en 12/15 haces anómalos izquierdos (80 por ciento) y en 4/6 derechos (67 por ciento), en 10/12 pacientes con preexitación (83//) y 6/9 haces ocultos (67 por ciento) (diferencias no significativas). El buen éxito se obtuvo en 76 por ciento (16/21) del total de pacientes, pero éste aumentó a 84 por ciento (p=0,048 Fisher) después de eliminar los pacientes con malformaciones congénitas. Las complicaciones observadas incluyeron obstrución arterial con síndrome de compartimiento y perforación con taponamiento (un caso de cada una). La ablación por radiofrecuencia es un tratamiento adecuado y definitivo en niños con taquicardia paroxística supraventricular,independientemente de la localización de la vía anómala y la presencia de preexitación, pero puede fracasar en casos de malformaciones cardíacas. Las complicaciones de importancia son poco frecuentes, pero pueden llegar a ser graves, lo que exige una rigurosa selección de los pacientes a estudiar

Fulguración por radiofrecuencia de haces paraespecíficos / Fulguration by radiofrecuency of paraspecific bundles

Between august 1991 and august 1993, 75 patients (42 male) with Wolff Parkinson White syndrome (43 concealed) were subjected to radiofrequency ablation of accesory pathway at our institution. 55 had left, 8 postero septal, 2 anteroseptal and 10 right accesory pathways. A retrograde aortic technique with placement of the ablation catheter in close proximity to the mitral annulus was used for most of the patients with left accesory pathways and for some with posteroseptal pathways were ablated using a right heart approach placing the ablation catheter in the tricuspid annulus. Ablation was successful in 61 patients (81 per cent ). One subject developed a fatal cardiac tamponade after a transeptal catheterization and was unrelated to the ablation per se. It is concluded that radiofrequency ablation of accesory pathways is a curative procedure for a great majority of patients with Wolf Parkinson White syndrome

La inversión precoz de la onda T en el electrocardiograma contribuye a predecir permeabilidad coronaria post trombolisis en el infarto agudo al miocardio / Early T wave inversion in electrocardiogram is a significant predictor of late coronary artery patency after thrombolysis in acute myocardial infarction

En el IAM los criterios de clásicos de reperfusión son la disminución del dolor, la reducción del supradesnivel del ST, las arritmias de reperfusión y la elevación precoz de CPK. Sin embargo, el valor predictivo de ellos es bajo. Evaluamos si la inversión precoz de la onda T (* 24 hrs) en (* 2) derivaciones ECGs contiguas contribuye a predecir permeabilidad de la arteria coronaria del área infartada. Analizamos 60 pacientes consecutivos con IAM y trombólisis sistémica, 33 pts. con IAM anterior y 27 con IAM inferior, estudiados con coronariografía dentro de 5 días de evolución del IAM. La arteria coronaria se encontró permeable en 40 pts. (66,6%) y obstruida en 20 pts. (33,3%). En el análisis univariado los criterios se asociaron a reperfusión fueron la inversión precoz de la onda T (p < 0,001), la reducción del supradesnivel de ST (p = 0,01) y la elevación precoz de CPK (p = 0,015). En el análisis multivariado mediante regresión logística paso a paso sólo la inversión precoz de la onda T fue significativa para predecir permeabilidad de la arteria coronaria del IAM. Concluimos que la inversión precoz de la onda T contribuye a predecir permeabilidad de la arteria coronaria post trombólisis sistémica

Trombólisis sistémica precoz en el infarto agudo del miocardio: resultados clínicos y angiográficos / Systemic early thrombolysis during myocardial infarction: clinical and angiographic results

Systemic thrombolysis is an effective therapy for acute myocardial infarction, since it restores coronary flow and contributes to preserve left ventricular function. We analyzeour experience with intravenous thrombolytic therapy in 45 cases with acute myocardialinfarction treated within 6 hours of onset of symptoms. 28 patients had anterior and 17 inferior myocardial infarction. We treated 38 patients with streptokinase 1 to 1,5 million units infused during a during a 30 to 60 minute period and 7 patients with tissue plasminogen activator factor, 100 mg infused during 2 hours. Regression of chest pain and ST segment elevation and early CPK peaking (< 4 hours) were utilized as criteria for reperfusion. Accordingly 20 patients (64%) met these criteria. Coronary angiogram ws performed within 7 days in 38 patients. It disclosed a patent coronary artery in the infarcted area in 28 cases (74%). Transient hypotension with thrombolytic therapy was observed in 17 patients (38%) and bleeding complications in 3 cases (7%). Two patients (4%) died early after therapeutic failure. In summary we have confirmed that intravenous thrombolytic therapy is safe and effective in the early period of myocardial infarction and that is associated with a high incidence of clinical and angiographic reperfusion

Muerte súbita en el adulto joven sin cardiopatía demostrable: características clínicas y electrofisiológicas en 3 casos / Sudden cardiac death in 3 young patients without overt heart disease

We reported 3 young adult males who developed spontaneous ventricular fibrillation in the abscence of demonstrable heart disease. Extensive clincial and elelcrophysiilogic evaluation failed to disclose a cause for the arrhythmia. Antiarrhythmic drugs were empirically used in all patients but 2 of then eventually died. Thus, unexplained ventricular fibrillation without demonstrable heart disease carries a serious short term prognosis. An implantable cardiovertodefibrillator may be the therapy of choice in these cases

Taquicardia ventricular sensible a verapamil: una entidad clínica y electrofisiológica / Recurrent paroxysmal ventricular tachycardia controlled by verapamil

Se presentan 4 pacientes, hombres, con edades que fluctúan entre los 16 y 51 años portadores de Taquicardia Ventricular Paroxística, recurrente sensible a Verapamil. En ninguno de ellos se demostró Cardiopatía Asociada. La morfología del QRS, durante la arritmia, se caracterizó por un aspecto de retardo derecho y desviación a izquierda del eje eléctrico. Este grupo de pacientes configuran una entidad clínica y electrocardiográfica que requiere de un manejo anti arrítmico diferente