Factores determinantes de éxito de la rehabilitación cardiovascular en pacientes coronarios sometidos a revascularización miocárdica / Cardiovascular Rehabilitation in patients following myocardial revascularization: factors associated to program success

Resumen: Introducción: La rehabilitación cardiovascular ha demostrado tener efectos beneficiosos en pacientes con antecedentes de patología coronaria. Objetivos: Identificar los factores que determinan el resultado de un programa de rehabilitación cardiovascular (PRC) aplicado a pacientes coronarios revascularizados. Métodos: 67 pacientes sometidos a cirugía de bypass o angioplastia fueron evaluados en su capacidad funcional mediante el test de marcha de 6 minutos (TM) al inicio y al completar el programa de rehabilitación cardiovascular. La distancia recorrida en el test de marcha fue correlacionada con la edad, capacidad funcional previa al PRC, tiempo en completar el pro-grama, tiempo que media entre la intervención y el inicio del programa, duración del programa y tipo de revascularización. Además, se comparó el incremento de la capacidad funcional entre los pacientes que fueron derivados a 36 sesiones con los referidos a solo 12. Resultados: 67 pacientes cumplieron los criterios para evaluación del PRC. Globalmente, se observó una mejoría de 12% (511,4 a 573,4 m) en la distancia del TM (p<0.001)). El mayor beneficio, en términos de distancia en el TM se obtuvo al efectuar un programa con más sesiones (36 vs 12) con valores de 20% y 8%, respectivamente (p<0.002). El poder terminar el PRC de 36 sesiones más rápidamente (entre 10 y 13 semanas vs entre 14 y 24 semanas se asoció a una mayor incremente en el TM con valores de 19% vs 10%, respectivamente (p<0,003). El incremento en el TM no difirió entre 3 grupos de edad (desde 49 a 85 años); en el tiempo que transcurre entre la intervención y el inicio del PRC (antes vs después de la 8a semana post revascularización), al tipo de revascularización a la que fue sometido el paciente (cirugía o angioplastía) y a la capacidad funcional previa que estos presentan al inicio del PRC. Conclusión: El PRC es efectivo en mejorar significativamente la capacidad funcional de pacientes revascularizados, especialmente cuando el número de sesiones del programa es mayor y cuando se realiza con una frecuencia de al menos 3 veces por semana. El PRC es igualmente efectivo en pacientes enviados a rehabilitación en forma más precoz, como también lo es en sujetos más añosos. Estos efectos fueron independientes del tipo de revascularización.

Abstracts: Introduction : Background: Cardiovascular Rehabilitation Programs (CRP) have been shown to produce be-neficial effects in patients with coronary artery disease. Aim: to identify factors associated to CRP success in patients who underwent myocardial revascularization Methods: 67 patients who underwent coronary artery bypass surgery (CABG) or percutaneous coronary artery angioplasty (PTCA) were evaluated for functional capacity by means of a standard 6 min walking test (6mWT), before and after completion of the CRP. Distance covered during the test was correlated with age, prior functional class, time employed to complete CRP, time from coronary intervention and CRP initiation, CRP duration and type of revascularization. In addition, patients referred for a 36 sessions CRP were compared to those referred to only 12 sessions. Results: 67 patients met inclusion criteria. Overall, there was a 12% increase (511,4 to 573,4 m) in 6mWT distance (p<0.001). The greatest benefit was obtained with the 36 session CRP as compared to a 12 session CRP (20 vs 8% (p<0.002). Also, completion of a 36 session CRP between 10 and 13 weeks compared to 14 to 24 weeks revealed a greater benefit in the former group (19% vs 10%, respectively (p<0.003). There was no difference in 6minWT distance in 3 groups of age (extending from 49 to 85 years-old); In addition, time from intervention to initiation of CRP (before vs after 8 weeks), type of revascularization or functional capacity at the beginning of CRP showed any difference in 6mWT distance. Conclusion: CRP is a highly effective intervention to improve functional capacity in patients following myocardial revascularization, more so when more sessions are employed and when at least 3 sessions per week are implemented. The program is equally effective in patients starting CRP early after revascularization, and benefit is independent from patient age.

Cintura e índice de masa corporal: los mejores predictores antropométricos en la reducción y progresión de la agregación de factores de riesgo cardiometabólicos / Waist and body mass index: The best anthropometric predictors in the reduction and progression of the aggregation of cardiometabolic risk factor

El objetivo de este estudio fue determinar el impacto de la variación de distintas mediciones antropométricas en la evolución del síndrome metabólico (SM). El estudio fue prospectivo en 178 sujetos que asistieron a un programa de salud cardiovascular entre el año 2013 y 2016. Se recolectaron datos demográficos, historia médica, factores de riesgo cardiovascular, y se midió perfil lipídico, glicemia de ayuno, presión arterial y medidas antropométricas (IMC, perímetro de cintura y cadera y % de grasa corporal). Se consideró la agregación de 2 o más componentes de síndrome metabólico (SM), excluyendo cintura y se determinó la probabilidad de reversión del SM, considerándose como la reducción desde 2 o más componentes a 1 o ninguno. El tiempo de seguimiento promedio fue de 2 años. La edad promedio fue de 40 años y 37% eran mujeres. Según los modelos de odds proporcionales, ajustados por edad, sexo y tiempo de seguimiento, aquellos sujetos con 2 o más componentes de SM triplicaron su probabilidad de revertir el SM por cada reducción de 1 Kg/m2 de IMC por año (OR IMC = 3,03; 1,74-5,28; p<0,001). En el caso de cintura, esta probabilidad aumentó en 52% por la reducción de 1 cm por año (ORcintura =1,52; 1,28-1,81; p<0,001). Finalmente una reducción de 0,01 en el índice cintura/cadera aumentó en 26% la probabilidad de revertir el SM (ORcintura/cadera =1,26; 1,06-1,491; p<0,01); sin embargo, el % de grasa corporal no tuvo un efecto significativo Los cambios en IMC y circunferencia de cintura serían los parámetros antropométricos más confiables para monitorear la evolución del SM(AU)

The objective of this study was to determine the impact of variation of different anthropometric parameters at follow-up in the evolution of the metabolic syndrome (MetS). Prospective study in 178 subjects who attended a cardiovascular health program between 2013 and 2016. Demographical data, medical history and cardiovascular (CV) risk factors (RFs) were collected. In addition, fasting lipid profile, blood glucose, blood pressure and anthropometrical parameters (BMI, WC, hip, and fat percentage) were measured. To determine the evolution of MetS, the clustering of 2 or more of the MetS components were considered, excluding WC. Odds proportional models adjusted by age, sex and time of follow-up were built to determine the probability of reverting the MetS. MetS reversion was considered as the reduction to 1 or 0 components in subjects with 2 or more. Mean follow-up time was 2 years. Mean age was 40 years old and 37% were women. According to the odds proportional models, subjects tripled their chance of reverting MetS for each 1 kg/m2 of BMI reduction (ORBMI=3.03; 1.74-5.28; p<0.001). For WC, the chance of reverting MetS increased 52% for each reduction of 1 cm of waist (ORwaist =1.52; 1.28-1.81; p<0.001). A reduction of 0.01 in the waist to hip ratio increased in 26% the chance of reverting MetS (ORwaist/hip=1.26; 1.06-1.491; p<0.01); however, fat percentage did not have a significant effect on the evolution of the MetS. BMI and WC are the most reliable anthropometrical parameters for monitoring the evolution of MetS aggregation in the out-patient clinical setting(AU)

Efecto de un modelo de apoyo telefónico en el auto-manejo y control metabólico de la Diabetes tipo 2, en un Centro de Atención Primaria, Santiago, Chile / Effect of a tele-care model on self-management and metabolic control among patients with type 2 diabetes in primary care centers in Santiago, Chile

Background: Telephone based self-management support may improve the metabolic control of patients with type 2 (DM2) diabetes if it is coordinated with primary care centers, if telephone protocols and clinical guidelines are used and if it is provided by nurses trained in motivational interviewing. Aim: To assess the efficacy ofi a tele-care self-management support model (ATAS) on metabolic control of patients with DM2 attending primary care centers in a low income area in Santiago, Chile. Material and Methods: Two primary care centers were randomly assigned to continue with usual care (control group, CG) or to receive additionally 6 telecare self-management support interventions (IG) during a 15 month period. Glycosylated hemoglobin (HbA1c) was used to measure metabolic control of DM2; the “Summary of Diabetes Self-care Activities Measure” and the “Spanish Diabetes Self-efficacy” scale were used to measure self-management and self efficacy, respectively. Changes in the use of health services were also evaluated. Results: The IG maintained its HbA1c level (baseline and final levels of 8.3 ± 2.3 percent and 8.5 ± 2.2 percent respectively) whereas it deteriorated in the CG (baseline and final levels of 7.4 ± 2.3 and 8.8 ± 2.3 percent respectively, p < 0.001). The perception of self-efficacy in the IG improved while remaining unchanged in the CG (p < 0.001). Adherence to medication, physical activity and foot care did not change in either group. In the IG, compliance to clinic visits increased while emergency care visits decreased. Conclusions: The ATAS intervention, in low income primary care centers, significantly increased the probability of stabilizing the metabolic control of patients with DM2 and improved their use of health services.

La atorvastatina no modifica el incremento agudo de los niveles de p-selectina y fibrinógeno inducido con esfuerzo físico máximo / Atovastatin does not modify the acutely increased levels of P-selectin and fibrinogen induced by maximal physical exercise

Introducción: Las estatinas han demostrado disminuir los eventos cardiovasculares en sujetos con y sin enfermedad aterosclerótica establecida. Se ha demostrado, que sus efectos benéficos no sólo dependen de la reducción del colesterol, sino que también podrían ser secundarios a otros efectos de las estatinas, como su efectos de reducción de inflamación y/ o trombogénesis entre otros. Sin embargo, no existen trabajos que demuestren que las estatinas sean capaces de frenarla activación de la cascada de inflamación y/o trombogénesis. Objetivos: Determinar el efecto de la administración oral de atorvastatina por 7 días sobre los niveles plasmáticos de proteína C- reactiva ultrasensible (PCR us), fibrinógeno y P-selectina, pre y post prueba de esfuerzo máximo inmediato y a las 24 horas de su ejecución. Métodos: Ensayo clínico en 50 hombres sanos (18 a 50 años), randomizado atorvastatina 80 mg/día - placebo por 7 días, doble ciego. Muestras tomadas en sangre para PCRus, fibrinógeno y P-selectina, perfil lipídico, creatin kinasa y transaminasas hepáticas, pre y post test de esfuerzo, y a las 24 horas. Los resultados para datos continuos se expresan como medias +/- desviación estándar, test de student para muestras independientes, ANOVA para muestras repetidas. Programa estadístico SPSS 14.0. Resultados: Un grupo de 44 sujetos completaron el estudio: atorvastatina 80 mg (n=24) o placebo (n=20). En el grupo atorvastatina, después de una semana de tratamiento, los niveles de LDLc disminuyeron en 38 por ciento (LDL basal: 97 +/- 27 mg/dL vs LDL post: 62 +/- 31 mg/dL, p < 0.001). Sin embargo, no se observaron cambios en ese mismo período en los niveles de PCRus, fibrinógeno y P-selectina con respecto a placebo. Los niveles de fibrinógeno se elevaron 8 por ciento entre la etapa pre y post ejercicio inmediato (341 +/- 56 mg/dL vs 368 +/- 65 mg/dL, p<0.001), retornando a los niveles basales a las 24 horas; no hubo diferencias entre atorvastatina - placebo...

Background: Chronic statin therapy is known to decrease ínflammation and platelet aggregation. However, little data exist regarding acute effect of statins upon these variables. Exercise can be used to induce ínflammation and platelet aggregation. Aim: to determine the acute effect of atorvastatin upon plasma levels of ultra sensitive C reactive protein (US-PCR), fibrinogen and P selectin before, immediately after and 24 hr following a maximal exercise test in healthy subjects. Methods: This was a double blind, randomized prospective study Fifty healthy male subjects (aged 18to 50years) received atorvastatin 80 mg or placebo daily for 7 days. US-PCR, fibrinogen, P-selectin, blood lipids, total creatin-kinase (CK) and transaminases were determined pre and immediately after maximal treadmill exercise. Repeat determinations were performed 24 following the test. Results were analyzed using the SPSS statistical package, and are expressed as mean +/- SD. Student's t and repeated measures ANOVA were used as appropriate. Results: 44 subjects completed the study (atorvastatin =24; placebo= 20). LDL cholesterol decreased from 97 +/- 27 to 62 +/- 31 mg/dl in the atorvastatin group (p<0.001). US-PCR, After 1 week, Fibrinogen and P-selectin were not significantly modified from baseline, and no differences were observed between groups (atorvastatin vs. control). However, fibrinogen increased 8 percent from baseline to immediately post exercise (341 +/- 6 vs. 368 +/- 65mg/dl (95 percent CI. 21/.3 - 33.6). 24hr after exercise, fibrinogen levels returned to baseline. Similar changes were observed for P-selectin (25 +/- 5, 28 +/- 1.7 ng/dl, baseline and post exercise respectively p<0.01), again returning to baseline 24hr after exercise. No significant changes were observed for US-PCR after exercise in neither group. CK increased 43 percent in the atorvastatin group and 12 percent in controls (NS). Conclusion: Atorvastatin...

Actividad física y potencia aeróbica: ¿Cómo influyen sobre los factores de riesgo cardiovascular clásicos y emergentes? / Association between cardiorespiratory fitness and cardiovascular risk factors in healthy individuals

Background: Cardio respiratory fitness (FIT) is associated with a better profile in most modifiable cardiovascular risk factors (RF). In Chile, sedentary lifestyle is highly prevalent, reaching almost 90 percent. Aim: To determine the association between FIT and traditional and emergent RF in a primary prevention population. Material and methods: We prospectively studied 1973 subjects (36 percent women, mean age 56± 13 years) without history of cardiovascular disease and absence of ischemic changes on exercise testing. We assessed cardiovascular RF and determined body mass index (BMI), waist circumference, systolic and diastolic blood pressure, fasting blood lipids, glucose, C-reactive protein (CRP) and fibrinogen. FIT was measured by a Sci f-reported physical activity questionnaire and by a maximal treadmill exercise test, expressed in metabolic equivalents (METs). Results: Subjects in the highest FIT according to the treadmill test had significantly lower BMI, waist circumference, systolic and diastolic blood pressure, total cholesterol, triglycerides, glucose, CRP and fibrinogen, and higher HDL cholesterol (adjusted by age and gender). LDL cholesterol did not show significant changes. The same pattern of RF (including LDL cholesterol) and CRP was observed when using Sci f-reported physical activity as a FIT parameter There was a significant association between both methods to measure FIT (p <0.0001, Chi-square Mantel-Haenszel). Conclusions: Our findings show that a better level off IT, assessed by exercise testing or through Sci f report is associated with improved levels of traditional and emergent RF.

Unidad de dolor torácico: primera experiencia en Chile / Chest pain unit: first experience in Chile

Background: In large series, nearly 60 percent of admissions for suspected acute coronary syndrome (ACS) had a non-coronary etiology of the pain. However, short term mortality of non recognized ACS patients, mistakenly discharged from the emergency room is at least twice greater than the expected if they would had been admitted. The concept of a chest pain unit (CPU) is a methodological approach developed to address these issues. Aim: To evaluate the efficacy of a CPU in the emergency room of a general hospital for evaluation of acute chest pain. Material and Methods: Prospective study of patients with chest pain admitted in the CPU. After a clinical, electrocardiographic and laboratory evaluation with cardiac injury serum markers, patients were stratified in three risk groups, based on the likelihood of ACS of the American Heart Association. High probability patients were admitted to the Coronary Unit (CU) for treatment. Moderate probability patients remained in the CPU for further evaluation and low probability patients were discharged with telephonic follow-up. Results: Of 407 patients, 35, 30 and 35 percent were stratified as high, intermediate and low probability ACS, respectively. Among patients admitted with high probability, 73 percent had a confirmed ACS diagnosis. Among intermediate probability patients, 86 percent were discharged after an evaluation in the CPU without adverse events in the follow-up. Conclusion: Structured risk evaluation approach in a CPU improves the management of acute chest pain, identifying high probability patients for fast admission and start of treatment in a CU and allowing safe discharge of low probability ones.

Relación entre capacidad aeróbica máxima, componentes del síndrome metabólico e inflamación subclínica en sujetos estudiados en una Unidad de Cardiología Preventiva Ambulatoria / Relationship between aerobic capacity, metabolic syndrome components and chronic subclinical inflammatory markers in subjects attending a primary prevention clinic

Antecedentes: El síndrome metabólico (SMET) está presente en uno de cada 4 sujetos en Chile. Existiría una relación directa entre el SMET y la inflamación subclínica crónica determinada por proteína C-reactiva ultrasensible (PCRus). La actividad física se asocia a un aumento en la sensibilidad a insulina y menor desarrollo de SMET y diabetes. Existe escasa información sobre la relación entre la actividad física, SMET y PCRus. Objetivos: Determinar la relación entre la capacidad aeróbica determinada por ergometría, los factores de riesgo del SMET y la inflamación subclínica en una población presuntamente sana. Métodos: Estudio prospectivo en una población estudiada en una unidad de cardiología preventiva ambulatoria entre noviembre de 2003 y agosto de 2005. En todos los sujetos se efectuó una evaluación sobre factores de riesgo cardiovascular, medición de IMC, cintura, cadera, perfil de lípidos, glicemia de ayuno, PCRus (desde marzo 2005), presión arterial sistólica y diastólica (PAS-PAD) en 2 días alternos, y test de esfuerzo máximo (frecuencia cardíaca alcanzada > 85 por ciento de la teórica o percepción de esfuerzo en escala de Borg > 17) medido en equivalentes metabólicos (METS). Resultados: Se estudiaron 1587 individuos (1016 hombres) de edad promedio 52 +/- 12 años. La mayoría (67 por ciento) tenía sobrepeso u obesidad, y un 25 por ciento cumplía con los criterios (ATP III) para SMET. Se demostró una correlación significativa entre la actividad física medida en METS con la edad (r= 0.57, p<0.001) y con algunos de los componentes del SMET como glicemia (r= - 0.16, p<0.001); HDL(r= -0.09, p<0.001) y PAS (r= -0.3, p<0.001). En la siguiente tabla se muestra la distribución de componentes del SMET y PCRus según cuartiles de actividad física: Los niveles de PCRus fueron significativamente menores en sujetos con SMET (+) y con mayor capacidad aeróbica versus los con menor...

Background: The metabolic syndrome (MS) is present in 1 out of 4 subjects in Chile. A direct relation between the presence of metabolic syndrome and chronic subclinical inflammation as revealed by ultra sensitive C reactive protein (CRP) has been postulated. Physical activity is associated with an increased insulin sensitivity and a lower incidence of MS and diabetes. There is limited information about the relation between physical activity, the MS and subclinical inflammation in healthy subjects. Aim: To determine the relationship between aerobic capacity measured by treadmill exercise testing, the components of MS and subclinical inflammation in a presumably healthy population. Methods: A prospective study was carried out in a primary prevention cardiac unit between november 2003 and august 2005. Risk factors for cardiovascular disease were evaluated. BMI, waist and hip circumference, fasting glucose, CRP, systolic and diastolic blood pressure were measured. METS were determined through an exercise test set to achieve 85 percent of maximal heart rate or a level 17 of Borg’s perceived effort. Results: 1587 subjects (1016 males) with mean age 52 years (SD 12) were studied. Most were overweight or obese: 25 percent met ATP III criteria for MS. METS were significantly correlated to age (r 0.57, p<0.001), fasting glucose level (r -0.16, p<0.001), HDL (r -0.09, p<0.001) and systolic BP (r -0.3, p<0.001). The distribution of mean values for MS components and CRP according to quartiles of METS is shown below: Conclusion: A strong association between aerobic capacity, MS factors and subclinical inflammation is shown in this study. It is postulated that exercise leading to improvement in aerobic capacity may have a beneficial effect upon chronic inflammation and cardiovascular risk.

[Long-term results of repair versus replacement for degenerative mitral valve regurgitation]. / Resultados alejados de la reparación versus reemplazo en insuficiencia mitral degenerativa.

BACKGROUND: Mitral valve repair is considered better than mitral valve replacement for degenerative mitral regurgitation. AIM: To evaluate late clinical results of mitral valve repair as compared to mitral valve replacement in patients with degenerative mitral regurgitation. PATIENTS AND METHODS: All patients subjected to open heart surgery for degenerative mitral regurgitation between 1990 and 2002 were assessed for surgical mortality, late cardiac and overall mortality, reoperation, readmission to hospital, functional capacity and anticoagulant therapy. Eighty eight patients (48 males) had mitral valve repair and 28 (19 males) had mitral valve replacement (23 with a mechanical prosthesis). Mean age was 59.9 +/- 14.8 (SD) and 61.3 +/- 14.6 years, respectively. Sixty three percent of patients with repair and 50% of those with valve replacement were in functional class III or IV before surgery. RESULTS: Operative mortality was 2.3% for mitral valve repair and 3.6% for mitral valve replacement (NS). Also, there was no statistical difference in the need of reoperation during the follow-up period between both procedures (2.3% and 0%, respectively). Ninety four percent of the replacement patients but only 26% of the repair patients were in anticoagulant therapy at the end of the follow-up period (p < 0.001). Ten years survival rates were 82 +/- 6% for mitral valve repair and 54 +/- 11% for replacement. The corresponding cardiac related survival rates were 89 +/- 6% and 79 +/- 10%. At the end of follow-up, all surviving patients were in functional class I or II. Ten years freedom from cardiac event rates (death, cardiac related rehospitalization and reoperation) were 90 +/- 3% for mitral valve repair and 84 +/- 6% for replacement. CONCLUSION: Repair of the mitral valve offers a better overall survival and a better chance of freedom from cardiac events as well as need for anticoagulation 10 years after surgery.

[Prevalence of cardiovascular risk factors among patients suffering vascular events on admission and one year later]. / Insuficiente control de factores de riesgo en prevención secundaria cardiovascular.

BACKGROUND: International studies show a low compliance with norms for the management of cardiovascular risk factors. AIM: To assess the prevalence of risk factors in patients admitted for a coronary or vascular event and to evaluate the proportion of patients that normalize these factors after one year of follow up. MATERIAL AND METHODS: Three hundred and fifty seven patients aged 64+/-13 years (264 males), admitted to a University Clinical Hospital for a coronary or vascular event were studied. They were educated about cardiovascular risk factors and followed by their treating physicians for a mean of 11.9+/-2 months. During this period, smoking habits, body mass index. blood pressure, serum lipid levels, blood glucose and the appearance of new cardiovascular events were registered. RESULTS: One year survival was 96% (all 13 deaths were of cardiac origin). Eighty seven percent of patients were free of major cardiovascular events. At discharge from hospital and at the end of follow up 49% and 44% had a total cholesterol over 200 mg/dl respectively, 9,6% and 20,8% had systolic pressure over 140 mmHg. There was no diastolic hypertension in these patients, 27% and 31% had a body mass index over 25 kg/m2 and 2% smoked (versus 32% before the event). CONCLUSIONS: After one year of follow up, the prevalence of risk factors in patients that had suffered a cardiovascular event, continues to be high.

[Valve repair surgery for incompetent bicuspid aortic valves]. / Ciruguía reparadora de la válvula aórtica bicúspide insuficiente.

BACKGROUND: Surgical valve repair is a good alternative for correction of incompetent bicuspid aortic valve. AIM: To report the early and late surgical, clinical and ecochardiographic results of surgical repair of incompetent bicuspid aortic valves. PATIENTS AND METHODS: Retrospective review of medical records of 18 patients aged 19 to 61 years, with incompetent bicuspid aortic valve in whom a valve repair was performed. Four patients had infectious endocarditis and 17 were in functional class I or II. Follow up ranged from 3 to 113 months after surgery. RESULTS: A triangular resection of the prolapsing larger cusp, which included the middle raphe, was performed in 17 cases; in 13 of these, a complementary subcommisural annuloplasty was performed. In the remaining case, with a perforation of the non-coronary cusp, a pericardial patch was implanted; this procedure was also performed in 2 other cases. In 3 cases large vegetations were removed. Postoperative transesophageal echocardiography showed no regurgitation in 11 patients (62%) and mild regurgitation in 7 (38%). There was no operative morbidity or mortality. There were no deaths during the follow-up period. In 3 patients (17%) the aortic valve was replaced with a mechanical prosthesis, 8 to 108 months after the first operation. Reoperation was not needed in 93%+/-6,4% at 1 year and 85%+/-9,5% at 5 years, these patients were all in functional class I at the end of the follow-up period. 60% had no aortic regurgitation, 20% had mild and 20% moderate aortic regurgitation on echocardiographic examination. A significant reduction of the diastolic diameter of the left ventricle was observed, but there were no significant changes in systolic diameter or shortening fraction. CONCLUSIONS: Surgical repair of incompetent bicuspid aortic valves has low operative morbidity and mortality and has a low risk of reoperation.

Tratamiento quirúrgico de la insuficiencia tricúspide funcional: análisis de dos técnicas de valvuloplastía / Chirurgic treatment in functional tricuspid insufficience: analysis of two valvuloplasty techniques

Antecedentes: Los resultados precoces del tratamiento quirúrgico de la insuficiencia tricúspide con la técnica de González de Vega (G de V) y campentier (CE) son satisfactorios. Sin embargo, existen pocos estudios con evaluación clínica y ecocardiográfica tardía. Objetivos: Comparar los resultados a largo plazo de la valvuloplastía tricúspide con las 2 técnicas más usadas e identificar factores asociados a recidiva de la insuficiencia valvular. Métodos: Realizamos un análisis retrospectivos clínico y ecocardiográfico de pacientes operados entre 1990 y 2002. Hubo 54 pacientes (38 con G de V y 16 con CE) que cumplieron con los criterios de inclusión para el análisis comparativo: mayores de 15 años, insuficiencia tricúspide grados III o IV por ecocardiografía preoperatoria y evaluación clínica y ecocardiográfica con al menos 6 meses de seguimiento. Resultados: Ambos grupos fueron comparables en cuanto a sus características pre-operatorias. El seguimiento promedio fue de 49 ± 36 meses. La sobrevida actuarial en el grupo G de V fue de 84 por ciento al año y 75 por ciento a los 5 años. En el grupo CE fue de 72 por ciento y 62 por ciento respectivamente (p = NS). El 87 por ciento de los pacientes mejoraron en forma importante su capacidad funcional. La ecocardiografía de control alejado mostró ausencia o insuficiencia tricúspide grado (II en 12 (31,6 por ciento) de los pacientes del grupo G de V y en 10 (62,5 por ciento) de los pacientes del grupo CE. Se observó insuficiencia tricúspide grados III o IV en 26 pacientes (68,4 por ciento) con G de V y en pacientes (37,5 por ciento) con la técnica CE (p = 0,035). En ambos grupos se demostró una correlación significativa entre el grado de insuficiencia tricúspide alejada y la presión de arteria pulmonar (p = 0,001). Conclusión: La valvuloplastía de CE produce mejores resultados que la G de V a largo plazo. Consigue mejoría clínica y ausencia de regurgitación ecocardiográfica importante en 2/3 de los pacientes. La persistencia de hipertensión pulmonar se asoció a recidiva de regurgitación tricúspide.

[Valve repair surgery in infectious endocarditis]. / Cirugía valvular reparadora en endocarditis infecciosa.

BACKGROUND: Valve replacement has been the treatment of choice for patients with valvular complications of infectious endocarditis (IE). However, excellent results with valve repair allowed it to become a new therapeutic alternative for these patients. AIM: To evaluate the results of valve repair in patients with valvular complications of IE. PATIENTS AND METHODS: From January 1991 to December 2000, 14 patients with valvular complications of IE underwent valve repair. Mean age was 37.9 +/- 14.9. RESULTS: New York Heart Association (NYHA) class was 2.8 +/- 0.9. IE was located in the aortic in 6 (42%), in the mitral valve in 4 (29%) and in both valves in 4 cases (29%). Surgical indication was hemodynamic in 50% of the cases, echocardiographic in 29% and septic in 21%. Five aortic valves were bicuspid, 3 mitral valves were myxomatous and the rest were normal. The most common septic lesions were vegetations and leaflet perforations. A total of 23 aortic and 21 mitral valve repair procedures were performed. There were no deaths. Only 1 patient had a surgical complication (renal failure and prolonged mechanical ventilation). Follow-up was 100% complete. There was not late mortality. One patient with bone marrow aplasia required reoperation for a new episode of IE 19 months later. At the end of the follow-up NYHA class was 1.3 +/- 0.6 and echocardiography showed a mild or absence of valve regurgitation in most patients. CONCLUSIONS: Valve repair surgery in IE has good results, with advantages over valve replacement.

Desbalance autonómico y procoagulación debido a contaminación atmosférica en Santiago: un estudio prospectivo / Autonomic imbalance and procoagulation due to Santiago’s atmospheric pollution: a prospective study

La contaminación atmosférica (CA) está asociada a aumento de morbilidad cardiovascular a través de mecanismos poco conocidos. Postulamos que la CA por partículas finas se asocia a disminución de la variabilidad de la frecuencia cardíaca (VFC) y a aumento de parámetros procoagulantes. Métodos: Cohorte prospectiva de 6 meses de duración en Santiago (n=88; edad 57±1 años; 44 pts.s con enfermedad coronaria y 44 controles pareados por edad, sexo y comuna de residencia). En cada sujeto se realizó Holter de arritmias de 24 hrs y se determinó proteína C reactiva, viscosidad plasmática, hematocrito y recuento de plaquetas durante un episodio de aumento de la CA y 6 meses después. Se obtuvieron los niveles diarios contemporáneos de partículas PM 2,5 y se analizaron sus efectos sobre la VFC y sobre los parámetros circulantes utilizando modelos aditivos generalizados con ajuste por condiciones meteorológicas, condición caso/control, edad, sexo, índice de masa corporal, colesterol total y HDL, presión arterial sistólica y diastólica, creatinina y uso de aspirina o de betabloqueadores. Resultados: Las concentraciones elevadas de partículas PM 2,5 en el aire los días previos a la medición se asociaron en forma independiente y significativa (p<0,05) con aumento de la FC y disminución en la desviación standard de los intervalos RR normales (SDNN). Se observó además una asociación independiente y significativa (p<0,05) con aumento de la viscosidad plasmática, hematocrito, VHS y del recuento de plaquetas. Conclusiones: Los resultados muestran que la CA por partículas pequeñas disminuye la VFC y aumenta parámetros circulantes de procoagulación, que podrían ser mecanismos que expliquen un aumento de la morbimortalidad cardiovascular debido a CA.

[Long-term results of repair surgery of degenerative mitral insufficiency]. / Resultados alejados de la cirugía reparadora de la insuficiencia mitral degenerativa.

BACKGROUND: Mitral valve repair is probably the procedure of choice for the surgical treatment of degenerative mitral insufficiency. AIM: To evaluate the late results of mitral valve repair in degenerative mitral insufficiency. PATIENTS AND METHOD: The records of 88 patients who underwent mitral valve repair for degenerative mitral insufficiency from December 1991 through June 2002 were reviewed. Mean age was 59.9 years (range 22 to 82). At least moderate mitral insufficiency was present in every patient. Mean left atrial diameter was 55 mm and mean end diastolic and end systolic left ventricular diameters were 61 and 37 mm respectively. RESULTS: The most common underlying lesion was ruptured chordae tendineae (66%) and posterior leaflet prolapse (68%). The surgical procedure most frequently performed was quadrilateral resection of the posterior leaflet (68%). A Carpentier-Edwards ring was placed in 97% of patients. An associated procedure was performed in 34%. Operative mortality was 2.3%. A complete follow up was obtained in 93% of cases with a mean of 54 +/- 36 months. Overall survival rate was 98% at one year, 88% at 5 and 82% at 10 years. Free of cardiac death rates were 94% at 5 and 89% at 10 years. Only 2 patients were reoperated during follow up, resulting in a 98% reoperation free rate follow up. Functional class improved in all patients at the end of follow up. Late echocardiographic evaluation showed absent or minimal mitral regurgitation in 83% and mild mitral regurgitation in 17%. CONCLUSION: Good late results have been obtained with mitral valve repair, avoiding the inconveniences of prosthetic replacement. Therefore, mitral valve repair should be the procedure of choice to treat degenerative mitral insufficiency.

[A 36 years experience with implantable pacemakers. A historical analysis]. / Experiencia de 36 años con marcapasos implantables. Un análisis histórico.

BACKGROUND: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. AIM: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. MATERIAL AND METHODS: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificación de Chile (Chilean Civil and Identification Registry). RESULTS: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74% from 1988 to 1998. Complication rate was 42% in the 1963-1976 study period, it decreased to 10.6% in the 1977-1987 study period, and to 5.6% by 1988-1998. Only two patients died during surgery in the study period (0.08%). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52% at ten years, 33% at 15 years, and 21% at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. CONCLUSIONS: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures.

[Surgery for mitral valve insufficiency]. / Cirugía de la insuficiencia mitral isquémica.

BACKGROUND: Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, notwithstanding a relatively high mortality rate. OBJECTIVES: To evaluate the results of mitral valve replacement or repair in patients with IMR. PATIENTS AND METHODS: Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8% of surgical procedures on the mitral valve. RESULTS: Mean age was 67 +/- 9 years. Surgery was performed urgently in 19 patients (66.5%). NYHA functional class was 3.4 +/- 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83%) had concomitant myocardial revascularization. Overall surgical mortality was 24%; 26% for mitral replacement and 13% for mitral valve repair (p = 0.215). On follow up of 26 +/- 33 months, one year survival was 76 +/- 0.8% and 5 years survival was 59 +/- 12%. Excluding in hospital mortality, survival was 100% at one year and 78 +/- 14% at 5 years. Functional class improved in all survivors, to 1.4 +/- 0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58%, 1+ MR in 17% and 2+ MR in 25%. CONCLUSION: In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease.

Comparación de Tilt test con isoproterenol versus Tilt prolongado en pacientes con síncope neurocardiogénico / Comparison of Tilt test with isoproterenol versus prolonged Tilt in patients with neurocardiogenic syncope

El objetivo de este trabajo fue evaluar el rendimiento diagnóstico del tilt test o prueba de inclinación en forma prolongada (45 minutos) en 11 pacientes consecutivos con síncope neurocardiogénico documentado previamente con un tilt positivo con isoproterenol. Ninguno de los pacientes presentó en este segundo examen prolongado una prueba positiva, a pesar que todos ellos tenían una prueba previa positiva bajo isoproterenol. En conclusión, el rendimiento diagnóstico del tilt bajo isoproterenol es muy superior al del tilt prolongado (45 minutos) en pacientes que presentan síncope de etiología no precisada. Estos resultados sugieren fuertemente que es mucho más conveniente realizar la prueba sólo con isoproterenol, lo que acorta sustancialmente la duración y el costo del examen

Morbimortalidad asociada a bloqueo auriculoventricular en el infarto del miocardio de pared inferior / Morbidity and mortality in atriventricular block of acute inferior wall myocardial infarction

El infarto del miocardio (IAM) de pared inferior, complicado con bloqueo auriculoventricular (BAV) se asocia a mayor mortalidad a pesar de ser en muchos casos transitorio. Con el objeto de analizar las causas de esta mayor mortallidad se estudiaron 307 pacientes (pts) consecutivos con IAM inferior, dividiéndolos en 421 pts sin BAV (grupo I) y 66 pts con BAV de 2o. ó 3o. grado (grupo II). La mortalidad global fue 10.7 (8.3% grupo I, p<0.001). No encontramos diferencias en ambos grupos respecto a factores de riesgo (excepto para tabaquismo, que fué mayor en el grupo I, p<0.001), antecedente de IAM, angina crónica o insuficiencia cardíaca previa. Encontramos diferencias significativas en ambos grupos respecto a edad (61 ñ 12 grupos I vs 68 ñ 9 años grupo 2, p<0.001) y en niveles máximos de CPK x ñ DS (1513 ñ 1135 grupo I vs 1958 ñ 1293 UI/1 grupo II, p<0.01). Durante su evolución los pacientes del grupo II presentaron mayor incidencia de arritmias ventriculares complejas, (p<0.01), de arritmias supraventriculares p<0.01) y de insuficiencia cardíaca Killip III y IV, (p<0.0001). Se estudiaron 123 pts con coronariografía, 106 del grupo I y 17 pts del grupo II. En los pts con BAV se encontró mayor incidencia de enfermedad de 3 arterias (47% vs 28%) y de lesiones críticas asociadas de arterias descendente anterior y derecha (29% vs 12%, p<0.06). En conclusión, los pts con IAM inferior complicado de BAV tienen mayor mortalidad en relación a edad más avanzada, necrosis más extensa, más complicaciones asociadas, y mayor incidencia de lesiones asociadas de arterias descendente anterior y derecha