Perfil clínico y angiográfico de las mujeres con infarto agudo al miocardio en un hospital nacional / Clinical and angiographic profile of women with acute myocardial infarction in a national hospital

Resumen Justificación: La cardiopatía isquémica es la principal causa de muerte de mujeres en Costa Rica, y su incidencia ha aumentado con los años. A pesar de esto, hay pocos estudios clínicos a este respecto en nuestro país. El objetivo del presente trabajo es presentar las principales características clínicas y angiográficas de un grupo de pacientes con infarto agudo del miocardio con la idea de establecer no solo sus particularidades sino permitir comparaciones con otras poblaciones. Métodos: Se trató de un estudio observacional, descriptivo y retrospectivo, de un periodo de cinco años, en el cual se incluyeron a las pacientes ingresadas con infarto del miocardio a la Unidad de Cuidados Intensivos. Se registraron datos demográficos, de evolución clínica, complicaciones, hallazgos angiográficos, tratamiento y desenlace. El análisis estadístico fue cuantitativo descriptivo, realizado con el programa informático SPSS v.21 (IBM Corp., EEUU) y éste consistió en cálculos de frecuencia, tendencia central, medidas de variabilidad de rango, percentiles, y chi-cuadrado. El protocolo de la investigación fue aprobado por el Comité Ético Científico del Hospital Rafael Ángel Calderón Guardia (DG-3380-2020). Resultados: De 190 pacientes se incluyeron un total de 54. La edad promedio fue de 60 años, con una mortalidad del 17,9%, la cual fue 5,4 % más alta que en los hombres. La mayor parte de las pacientes padecía de hipertensión arterial (74%), 24 (44,5%) eran taba- quistas y 23 (42,5%) tenían diabetes mellitus. Los síntomas más frecuentes fueron: dolor torácico, criodiaforesis y disnea. Se consideró que hubo dolor torácico atípico en 8 casos (15%). A 48 pacientes se le llevó a angioplastia coronaria y solo 35% la recibieron en tiempo oportuno. A 17 pacientes se les aplicó trombólisis farmacológica y solo en 3 pacientes fue exitosa. La arteria coronaria derecha y la arteria descendente anterior fueron los vasos responsables en la mayoría de los casos (19 casos (39,5%) cada uno de ellas.) Conclusión: Esta población tuvo síntomas isquémicos claros, con enfermedad coronaria severa y una mortalidad mayor que los hombres. En general la terapia farmacológica, así como la mecánica se aplicaron en forma tardía.

Abstrac Justification: The ischemic heart disease is the main cause of death of women in Costa Rica, and its incidence has increased with the years. In spite of this, there are few clinical studies in this respect in our country. The aim of this paper is to present the main clinical and angiographic characteristics of a group of patients with acute myocardial infarction in order to establish not only their particularities but also to allow comparisons with other populations. Methods: An observational, descriptive and retrospective study was carried out over a period of five years, in which patients admitted with myocardial infarction to the Intensive Care Unit were included. Demographic data, clinical evolution, complications, angiographic findings, treatment, and outcome were recorded. Statistical analysis was quantitative and descriptive, performed with SPSS v.21 software (IBM Corp., USA) and consisted of calculations of frequency, central tendency, measures of variability, percentiles, and chi-square. The Ethical Committee of the Hospital Rafael Angel Calderon Guardia approved the research protocol (DG-3380-2020). Results: A total of 54 out of 190 patients were included. The average age was 60 years, with a mortality rate of 17.9%, which was 5.4% higher than in men. Most of the patients suffered from arterial hypertension (74%), 24 (44.5%) were smokers and 23 (42.5%) had diabetes mellitus. The most frequent symptoms were chest pain, cryodiaphoresis and dyspnea. It was considered that there was atypical chest pain in 8 cases (15%). Forty-eight patients were taken for coronary angioplasty and only 35% received it in time. Pharmacological thrombolysis was applied to 17 patients, and it was successful in only 3 patients. The right coronary artery and the anterior descending artery were the vessels responsible in most cases (19 cases (39.5%) each). Conclusión: This population had clear ischemic symptoms, with severe coronary disease and higher mortality than men. In general, pharmacological as well as mechanical therapy was applied late.

Elaboration and validation of an ICNP® terminology subset for patients with acute myocardial infarction / Elaboración y validación de subconjunto terminológico CIPE ® para la persona con infarto agudo del miocardio / Elaboração e validação de subconjunto terminológico CIPE® para a pessoa com infarto agudo do miocárdio

ABSTRACT Objective: To elaborate a terminological subset for the International Classification for Nursing Practice (ICNP®) for patients with acute myocardial infarction using the Activities of Living Model. Method: A methodological study which followed the guidelines of the International Nursing Council and was based on theoretical framework of the Activities of Living Model for its elaboration. Content validation was performed by 22 nursing specialists. Results: Twenty-two (22) diagnoses and 22 nursing outcomes were elaborated. Of these, 17 nursing diagnosis statements and 17 nursing outcome statements presented Content Validity Index (CVI) ≥ 0.80. Of the 113 elaborated nursing interventions, 42 reached a CVI ≥ 0.80, and 51 interventions made up the terminological subset after the expert suggestions. Conclusion: The ICNP® was suitable for use with the Activities of Living Model, having compatible terms with those used in clinical nursing practice, and valid for construction of the terminological subset for patients with acute myocardial infarction and most likely to facilitate clinical nursing judgment.

RESUMEN Objetivo: Elaborar el subconjunto terminológico de la Clasificación Internacional para la Práctica de Enfermería (CIPE®) para la persona con infarto agudo del miocardio, utilizando el Modelo de Actividades de Vida. Método: Estudio metodológico, que siguió las orientaciones del Consejo Internacional de Enfermeros y tuvo como base teórica el Modelo de Actividades de Vida para su elaboración. La validación de contenido fue realizada por 22 enfermeros expertos. Resultados: Fueron elaborados 22 diagnósticos y 22 resultados de enfermería. De esos, 17 enunciados de diagnósticos y 17 resultados de enfermería presentaron Índice de Validez de Contenido (IVC) ≥ 0,80. De las 113 intervenciones enfermeras diseñadas, 42 alcanzaron IVC ≥ 0,80 y, después de sugerencias de los expertos, 51 intervenciones compusieron el subconjunto terminológico. Conclusión: La CIPE® se mostró adecuada para empleo con el Modelo de Actividades de Vida, contando con términos compatibles con los utilizados en la práctica clínica enfermera, siendo válido para la construcción del subconjunto terminológico para la persona con infarto agudo del miocardio y probablemente para la facilitación del juicio clínico enfermero.

RESUMO Objetivo: Elaborar o subconjunto terminológico da Classificação Internacional para a Prática de Enfermagem (CIPE®) para a pessoa com infarto agudo do miocárdio, utilizando o Modelo de Atividades de Vida. Método: Estudo metodológico, que seguiu as orientações do Conselho Internacional de Enfermeiros e teve como base teórica o Modelo de Atividades de Vida para a sua elaboração. A validação de conteúdo foi realizada por 22 enfermeiros especialistas. Resultados: Foram elaborados 22 diagnósticos e 22 resultados de enfermagem. Destes, apresentaram Índice de Validade de Conteúdo (IVC) ≥ 0,80 17 enunciados de diagnósticos e 17 resultados de enfermagem. Das 113 intervenções de enfermagem elaboradas, 42 alcançaram IVC ≥ 0,80, e, após sugestões dos especialistas, 51 intervenções compuseram o subconjunto terminológico. Conclusão: A CIPE® mostrou-se adequada para uso com o Modelo de Atividades de Vida possuindo termos compatíveis com os utilizados na prática clínica do enfermeiro, sendo válida para a construção do subconjunto terminológico para a pessoa com infarto agudo do miocárdio e provavelmente para a facilitação do julgamento clínico de enfermagem.

Remodelamento miocárdico após grandes infartos converte potenciação pós-pausa em decaimento da força em ratos / Myocardial remodeling after large infarcts in rat converts post rest-potentiation in force decay / Miocárdio remodelado después de grandes infartos en ratas convierte potenciación post-pausa en disminucion de la fuerza

FUNDAMENTO: A Contração Pós-Repouso (CPR) do músculo cardíaco fornece informações indiretas sobre a manipulação de cálcio intracelular. OBJETIVO: Nosso objetivo foi estudar o comportamento da CPR e seus mecanismos subjacentes em camundongos com infarto do miocárdio. MÉTODOS: Seis semanas após a oclusão coronariana, a contratilidade dos Músculos Papilares (MP) obtidos a partir de camundongos submetidos à cirurgia sham (C, n = 17), com infarto moderado (MMI, n = 10) e grande infarto (LMI, n = 14), foi avaliada após intervalos de repouso de 10 a 60 segundos antes e depois da incubação com cloreto de lítio (Li+) em substituição ao cloreto de sódio ou rianodina (Ry). A expressão proteica de SR Ca(2+)-ATPase (SERCA2), trocador Na+/Ca2+ (NCX), fosfolambam (PLB) e fosfo-Ser (16)-PLB foi analisada por Western blotting. RESULTADOS: Os camundongos MMI apresentaram potenciação de CPR reduzida em comparação aos camundongos C. Em oposição à potenciação normal para camundongos C, foram observadas degradações de força pós-repouso nos músculos de camundongos LMI. Além disso, a Ry bloqueou a degradação ou potenciação de PRC observada em camundongos LMI e C; o Li+ inibiu o NCX e converteu a degradação em potenciação de CPR em camundongos LMI. Embora os camundongos MMI e LMI tenham apresentado diminuição no SERCA2 (72 ± 7% e 47 ± 9% de camundongos controle, respectivamente) e expressão protéica de fosfo-Ser16-PLB (75 ± 5% e 46 ± 11%, respectivamente), a superexpressão do NCX (175 ± 20%) só foi observada nos músculos de camundongos LMI. CONCLUSÃO: Nossos resultados mostraram, pela primeira vez, que a remodelação miocárdica pós-IAM em camundongos pode mudar a potenciação regular para degradação pós-repouso, afetando as proteínas de manipulação de Ca(2+) em miócitos.

BACKGROUND: Post-rest contraction (PRC) of cardiac muscle provides indirect information about the intracellular calcium handling. OBJECTIVE: Our aim was to study the behavior of PRC, and its underlying mechanisms, in rats with myocardial infarction. METHODS: Six weeks after coronary occlusion, the contractility of papillary muscles (PM) obtained from sham-operated (C, n=17), moderate infarcted (MMI, n=10) and large infarcted (LMI, n=14) rats was evaluated, following rest intervals of 10 to 60 seconds before and after incubation with lithium chloride (Li+) substituting sodium chloride or ryanodine (Ry). Protein expression of SR Ca(2+)-ATPase (SERCA2), Na+/Ca2+ exchanger (NCX), phospholamban (PLB) and phospho-Ser(16)-PLB were analyzed by Western blotting. RESULTS: MMI exhibited reduced PRC potentiation when compared to C. Opposing the normal potentiation for C, post-rest decays of force were observed in LMI muscles. In addition, Ry blocked PRC decay or potentiation observed in LMI and C; Li+ inhibited NCX and converted PRC decay to potentiation in LMI. Although MMI and LMI presented decreased SERCA2 (72±7% and 47±9% of Control, respectively) and phospho-Ser16-PLB (75±5% and 46±11%, respectively) protein expression, overexpression of NCX (175±20%) was only observed in LMI muscles. CONCLUSION: Our results showed, for the first time ever, that myocardial remodeling after MI in rats may change the regular potentiation to post-rest decay by affecting myocyte Ca(2+) handling proteins.

FUNDAMENTO: La Contracción pos pausa (CPP) del músculo cardíaco provee informaciones indirectas sobre la manejo del calcio intracelular. OBJETIVO: Nuestro objetivo fue estudiar el comportamiento de la CPP y sus mecanismos subyacentes en Ratas con infarto de miocardio. MÉTODOS: Seis semanas después de la oclusión coronaria, la contractilidad de los Músculos Papilares (MP) obtenidos a partir de Ratas sometidos a falsa cirurgia (C, n = 17), con infarto moderado (MMI, n = 10) y gran infarto (LMI, n = 14), fue evaluada después de pausas de estímulos de 10 a 60 segundos antes y después de la incubación con cloruro de litio (Li+) en substitución del cloruro de sodio o rianodina (Ry). La expresión proteica de SR Ca(2+)-ATPasa (SERCA2), intercambiador Na+/Ca2+ (NCX), fosfolamban (PLB) y fosfo-Ser (16)-PLB fue analizada por Western blotting. RESULTADOS: Los Ratas MMI presentaron potenciación de CPP reducida en comparación a los Ratas C. En oposición a la potenciación normal para Ratas C, fueron observadas decaimientos de fuerza post-reposo en los músculos de Ratas LMI. Además de eso, la Ry bloqueó la decaimiento o potenciación de PRC observada en Ratas LMI y C; el Li+ inhibió el NCX y convirtió la decaimiento en potenciación de CPP en Ratas LMI. Aunque los Ratas MMI y LMI hayan presentado disminución en el SERCA2 (72 ± 7% y 47 ± 9% de Ratas control, respectivamente) y expresión proteica de fosfo-Ser16-PLB (75 ± 5% y 46 ± 11%, respectivamente), la superexpresión del NCX (175 ± 20%) sólo fue observada en los músculos de Ratas LMI. CONCLUSIÓN: Nuestros resultados mostraron, por primera vez, que el remodelado miocárdico post-IAM en Ratas puede cambiar la potenciación regular para decaimiento post-reposo, afectando las proteínas de manejo del Ca(2+) en miocitos.

Myocardial remodeling after large infarcts in rat converts post rest-potentiation in force decay.

BACKGROUND: Post-rest contraction (PRC) of cardiac muscle provides indirect information about the intracellular calcium handling. OBJECTIVE: Our aim was to study the behavior of PRC, and its underlying mechanisms, in rats with myocardial infarction. METHODS: Six weeks after coronary occlusion, the contractility of papillary muscles (PM) obtained from sham-operated (C, n=17), moderate infarcted (MMI, n=10) and large infarcted (LMI, n=14) rats was evaluated, following rest intervals of 10 to 60 seconds before and after incubation with lithium chloride (Li(+)) substituting sodium chloride or ryanodine (Ry). Protein expression of SR Ca(2+)-ATPase (SERCA2), Na(+)/Ca(2+) exchanger (NCX), phospholamban (PLB) and phospho-Ser(16)-PLB were analyzed by Western blotting. RESULTS: MMI exhibited reduced PRC potentiation when compared to C. Opposing the normal potentiation for C, post-rest decays of force were observed in LMI muscles. In addition, Ry blocked PRC decay or potentiation observed in LMI and C; Li(+) inhibited NCX and converted PRC decay to potentiation in LMI. Although MMI and LMI presented decreased SERCA2 (72±7% and 47±9% of Control, respectively) and phospho-Ser(16)-PLB (75±5% and 46±11%, respectively) protein expression, overexpression of NCX (175±20%) was only observed in LMI muscles. CONCLUSION: Our results showed, for the first time ever, that myocardial remodeling after MI in rats may change the regular potentiation to post-rest decay by affecting myocyte Ca(2+) handling proteins.

Fator prognóstico do infarto agudo do miocárdio com supradesnível de ST / Prognosis factor of acute myocardial infarction with ST elevation

Objetivos: Conhecer a relação entre a área cardíaca infartada observada no eletrocardiograma e os níveis séricos dos marcadores isquêmicos CPK e CK-MB com o desfecho dos pacientes.Métodos: Estudo transversal, documental, observacional e retrospectivo abrangendo 96 pacientes infartados atendidos no Hospital São José, em Criciúma, SC, no período de 2003 a 2005. As variáveis estudadas foram sexo, idade, área cardíaca infartada, nível de enzimas e desfecho dos pacientes. Resultados: Dos pacientes estudados, 73 (76,04%)eram do sexo masculino e 23 (23,96%) feminino com média de idade de 60,1 anos. Observou-se maior prevalênciada mortalidade no sexo feminino (p=0,033) e em idades mais avançadas (p=0,02). Houve maior freqüênciade infarto agudo do miocárdio na parede inferior, e maior mortalidade naqueles com lesão da parede ântero- lateral. Os níveis dos marcadores isquêmicos forammaiores no sexo feminino e nos pacientes que evoluíram para óbito, não mostrando relação com a mortalidadeem uma parede infartada específica.Conclusão: Das variáveis estudadas, sexo e idade foram estatisticamente significativas quando relacionadas com o desfecho dos pacientes. Na análise dos níveis enzimáticos em uma parede cardíaca específica, não se observou associação significativa com óbito.

Objectives: To know the relation between the infarct cardiac area detected in electrocardiogram andserum levels of the ischemic markers CPK and CKMB with outcome of the patients. Methods: Transversal, document, observational and retrospective study ranging 96 infarcted patients checked in São José Hospital in Criciúma City, SC, from 2003 to 2005. The variables studied were sex, age, infarct cardiac area, enzymes level and outcome of the patients. Results: From the studied patients, 73 (76,04%) weremale and 23 (23,96%) female, with median age of 60,05 years. It was observed more prevalence of the mortality in women (p=0,33) and in advanced ages (p=0,02). There were most frequency of acute myocardial infarction in the inferior wall and more mortality on those with ântero-lateral lesion. The ischemic markers levels werehigher in females and in patients who died, not showing relation with mortality in a specific infarcted wall. Conclusion: From the studied variables, sex and age were statistically significant when related with the outcome of the patients. In the enzymes level analysis of aspecific cardiac wall it wasn’t observed significant relation with death.

Sexo femenino y morbi-mortalidad intrahospitalaria por infarto agudo al miocardio en el Hospital Escuela Doctor Roberto Calderón Gutiérrez: septiembre 1998- abril 2006 / Female morbidity and mortality in acute myocardial infarction at the Hospital Doctor School Roberto Calderon Gutierrez: September 1998 - April 2006

La enfermedad arterial coronaria es la principal causa de muerte en mujeresposmenopáusicas en los países industrializados. Aunque el infarto agudo al miocardio (IAM) afecta más frecuentemente a hombres que a mujeres, la evolución del mismo acorto plazo es peor en mujeres. En estudios de seguimiento a largo plazo se sugiere que el riesgo de morir es menor o similar que en hombres, sin embargo, el tiempo de seguimiento y el ajuste de factores confusores han variado y aun más importante, la asociación entre los tratamientos y los controles no se ha examinado adecuadamente. La evolución de las mujeres con síndromes coronarios agudos es más difícil encomparación con los hombres; esta diferencia se da porque habitualmente son de mayor edad, mayor prevalencia de diabetes e hipertensión arterial. La prevalencia de mujeres ingresadas por infarto agudo de miocardio es inferior a la de varones y su pronóstico a corto plazo es peor. Los motivos de estas diferencias están en discusión. De acuerdo a los registros del Ministerio de Salud, las enfermedades del sistemacirculatorio son la principal causa de muerte en nuestro país, con distribución similar en hombres y mujeres (tasa de mortalidad de 78 y 75.4 por ciento espectivamente, ocupando la cardiopatía isquémica la principal causa de muerte en el país (aproximadamente 11.8 por ciento) y por departamentos. Las tesis monográficas realizadas hasta la fecha son de carácter epidemiológico. Debido al serio problema de salud que la cardiopatía isquémica, y particularmente el infarto agudo del miocardio, representan en nuestro país, y suparticular impacto en el sexo femenino, nos propusimos investigar las diferenciassexuales en los factores de riesgo y tratamientos empleados, y su asociación con la morbimortalidad intrahospitalaria por IAM. Se realizó un estudio de tipo cohorte en la fase aguda...

A proposed functional clinical classification predicts in-hospital and long-term survival in the setting of acute right ventricular infarction.

BACKGROUND: The objectives of the present investigation were to validate the prognostic role of a proposed Clinical Classification [CC], to evaluate the TIMI risk score [RS] and to establish whether the TIMI-RS should incorporate points for patients with acute right ventricular infarction [TIMI-RS-RVI]. METHODS AND RESULTS: A total of 523 RVI patients were classified on clinical and functional basis as: A, without right ventricular failure [RVF], B with RVF and C with cardiogenic shock. The CC was evaluated prospectively among 98 patients with RVI and retrospectively in 425 RVI patients. The TIMI-RS was evaluated prospectively among 622 patients with STEMI [anterior:277, inferior:247, RVI:98], and retrospectively in 425 RVI patients. The CC established differences among the 3-RVI Classes for in-hospital mortality [prospectively and retrospectively; p<0.01, p<0.001, respectively] that were maintained at 8 years [p < 0.001]. Patients with anterior and inferior STEMI, but not those with RVI revealed an association between outcome and TIMI-RS [p<0.001]. Testing for TIMI-RS-RVI did not result a good prognostic tool [ROC=0.9; excellent discrimination, but with a very poor "clinical calibration"]. CONCLUSIONS: The proposed CC allowed prediction of mortality at short- and long-term in the setting of acute RVI. The role of the TIMI-RS should be reevaluated prospectively as a prognostic tool in the scenario of RVI patients.

Value of adenosine infusion for infarct size determination using real-time myocardial contrast echocardiography.

BACKGROUND: Myocardial contrast echocardiography has been used for determination of infarct size (IS) in experimental models. However, with intermittent harmonic imaging, IS seems to be underestimated immediately after reperfusion due to areas with preserved, yet dysfunctional, microvasculature. The use of exogenous vasodilators showed to be useful to unmask these infarcted areas with depressed coronary flow reserve. This study was undertaken to assess the value of adenosine for IS determination in an open-chest canine model of coronary occlusion and reperfusion, using real-time myocardial contrast echocardiography (RTMCE). METHODS: Nine dogs underwent 180 minutes of coronary occlusion followed by reperfusion. PESDA (Perfluorocarbon-Exposed Sonicated Dextrose Albumin) was used as contrast agent. IS was determined by RTMCE before and during adenosine infusion at a rate of 140 mcg.Kg(-1).min(-1). Post-mortem necrotic area was determined by triphenyl-tetrazolium chloride (TTC) staining. RESULTS: IS determined by RTMCE was 1.98 +/- 1.30 cm2 and increased to 2.58 +/- 1.53 cm2 during adenosine infusion (p = 0.004), with good correlation between measurements (r = 0.91; p < 0.01). The necrotic area determined by TTC was 2.29 +/- 1.36 cm2 and showed no significant difference with IS determined by RTMCE before or during hyperemia. A slight better correlation between RTMCE and TTC measurements was observed during adenosine (r = 0.99; p < 0.001) then before it (r = 0.92; p = 0.0013). CONCLUSION: RTMCE can accurately determine IS in immediate period after acute myocardial infarction. Adenosine infusion results in a slight better detection of actual size of myocardial damage.

[On Q-wave and non-Q wave myocardial infarcts]. / Infartos miocárdicos con onda Q y sin onda Q.

Much has been said, and is still being said, on Q-wave and non-Q wave myocardial infarcts, trying to relate this electrocardiographic behavior with the culprit coronary arteries and the location of the damaged myocardium. However, it seems logic to bear in mind that the presence or absence of abnormal Q waves depends on the relation established between the zone of damaged myocardium and the width of the electrical endocardium. It must be recalled that the presence of normal Q waves is possible in leads that seem to move away from the first vector of ventricular activation. Besides, the electrical endocardium, i.e., the territory of distribution of Purkinje's network, is situated mainly in the lower half of the ventricles and is virtually absent in basal regions. This endocardium constitutes a histological-functional entity, since the Purkinje fibers, which receive at the same time the activation impulses, are depolarized simultaneously without producing differences in potential. Therefore, these fibers cannot supply an electrical contribution either in normal condition or in the presence of limited damage. Nevertheless, when the damaged zone reaches beyond the exterior limits of this endocardium, for example, in regions where it is small, the exploring electrode can register abnormal Q waves, due to the activation fronts that are moving away, followed by R waves originated in contiguous bands of non-damaged myocardium. We present two characteristic examples of the electrocardiographic manifestations of a transmural left ventricle infarct (QS complexes) and of a subendocardial infarct, reaching beyond the borders of the electrical endocardium (QR complexes). In both of these cases, the electrocardiographic data agree with the anatomical findings.

Infartos miocárdicos con onda Q y sin onda Q / On Q-wave and non-Q wave myocardial infarcts

Se habló mucho, y se sigue hablando, de infartos miocárdicos con onda Q y sin onda Q en las derivaciones correspondientes. Y se trata de relacionar el cuadro electrocardiográfico con las arterias coronarias afectadas y con la ubicación de la zona de miocardio inactivable. Pero debe tenerse presente que la existencia o no de ondas Q anormales -pueden hallarse ondas Q normales en las derivaciones que ven alejarse el primer vector de la activación ventricular- depende de la relación que se establece entre la extensión de la zona miocárdica dañada y la amplitud del llamado endocardio eléctrico. Tal relación varía en los diferentes individuos de la misma especie y según el nivel ventricular en donde se sitúa el miocardio dañado. De hecho, debe tenerse presente que el endocardio eléctrico, i.e. el territorio de distribución de la red de Purkinje, se encuentra en su mayor parte en la mitad inferior de ambos ventrículos y es prácticamente ausente en las regiones básales. Constituye éste una entidad histofuncional porque las fibras de Purkinje, que reciben al mismo tiempo los impulsos de activación, se despolarizan simultáneamente sin producir diferencias de potencial. Por lo tanto, no pueden dar una contribución eléctrica propia ni en condiciones normales, ni cuando sufren un daño circunscrito. Pero si el área dañada rebasa los límites externos de dicho endocardio, p. ej. en sitios donde éste es escaso, los electrodos exploradores correspondientes pueden registrar ondas Q anormales, debido a los frentes de activación que se alejan, seguidas de ondas R originadas en tiras de miocardio respetado. Presentamos dos ejemplos característicos, respectivamente, de las manifestaciones electrocardiográficas de un infarto transmural del ventrículo izquierdo (complejos ventriculares QS) y de un infarto subendocárdico que rebasa los límites externos del endocardio eléctrico (complejos ventriculares QR). En ambos casos, los hallazgos electrocardiográficos se correlacionan bien con los datos anatómicos.

Much has been said, and is still being said, on Q-wave and non-Q wave myocardial infarcts, trying to relate this electrocardiographic behavior with the culprit coronary arteries and the location of the damaged myocardium. However, it seems logic to bear in mind that the presence or absence of abnormal Q waves depends on the relation established between the zone of damaged myocardium and the width of the electrical endocardium. It must be recalled that the presence of normal Q waves is possible in leads that seem to move away from the first vector of ventricular activation. Besides, the electrical endocardium, i.e., the territory of distribution of Purkinje's network, is situated mainly in the lower half of the ventricles and is virtually absent in basal regions. This endocardium constitutes a histological-functional entity, since the Purkinje fibers, which receive at the same time the activation impulses, are depolarized simultaneously without producing differences in potential. Therefore, these fibers cannot supply an electrical contribution either in normal condition or in the presence of limited damage. Nevertheless, when the damaged zone reaches beyond the exterior limits of this endocardium, for example, in regions where it is small, the exploring electrode can register abnormal Q waves, due to the activation fronts that are moving away, followed by R waves originated in contiguous bands of non-damaged myocardium. We present two characteristic examples of the electrocardiographic manifestations of a transmural left ventricle infarct (QS complexes) and of a subendocardial infarct, reaching beyond the borders of the electrical endocardium (QR complexes). In both of these cases, the electrocardiographic data agree with the anatomical findings.

Aspectos práticos indicações e técnicas de implante de marcapasso provisório / Pratical aspects, indications and techniques of implantation of pacemaker

As indicações da estimulação cardíaca temporária são apresentadas em várias situações de infarto agudo, pós operatório de cirurgia cardíaca, pré operatório em geral, intoxicações medicamentosas e processos inflamatórios, entre outras.A técnica de estimulação é classificada em cinco tipos: cutânea-torácica, esofágica, miocárdica percutânea, epicárdica, descrevendo-se os procedimentos e os detalhes tático-técnicos.A utilização do marcapasso externo com a determinação dos limiares de estimulação e sensibilidade, a programação a ser establecida do gerador e os cuidados e condutas a serem tomados durante sua utilização são explicados.A vantagem da estimulação com sincronismo atrioventricular, apresentando-se o cabo elétrodo temporário quadripolar desenvolvido para estimulação VDD ou DDD, é ressaltada

[Evaluation and proposal of a classification for ventricular systolic interdependence with atrioventricular plane displacement in patients with first acute myocardial infarct]. / Interdependencia ventricular sistólica con el desplazamiento del plano auriculoventricular en pacientes con primer infarto del miocardio. Evaluación y propuesta de clasificación.

OBJECTIVE: Our objective was to evaluate and propose a classification of ventricular systolic interdependence with atrioventricular plane displacement (AVPD) in patients with acute myocardial infarction. MATERIAL AND METHODS: Eighty consecutive patients with first acute myocardial infarction event were studied. Two-dimensional- and M-mode echocardiogram were carried out. We measured the ejection fraction of both ventricles and the mitral and tricuspid AVPD. According to the acute myocardial infarction localization, patients were divided into three groups: group I: inferior or postero-inferior, group II: anterior, and group III: postero-inferior with right ventricle involvement. RESULTS: Eighty patients with first acute myocardial infarction were studied, 64 men and 16 women; the age average was 62 +/- 12.5 years. In group I there were 17 cases, in group II, 45 and in group III, 18. The left ventricular ejection fraction was, respectively, 50.3% +/- 11.1%, 37.7 +/- 8.6%, and 38.3 +/- 8.2% for groups I, II, and III (p <0.0001); the mitral AVPD was, respectively, 12.7 +/- 3.2 mm, 11.2 +/- 2.9 mm, and 9.9 +/- 2.7 mm (p = 0.024); the right ventricular ejection fraction was, respectively, 53.5 +/- 7.1%, 54.4 +/- 9% and 35.5 +/- 8.7% (p < 0.0001) and the tricuspid AVPD was, respectively, 20.1 +/- 3.6 mm, 19.9 +/- 4.6 mm, and 12.5 +/- 5.7 mm (p < 0.0001). With the above-mentioned results, we propose a ventricular systolic interdependence classification: A for group I (biventricular function preserved), B for group II (left damage and compensation of the right one), and C for group III (biventricular damage). CONCLUSIONS: The assessment of the ejection fraction of both ventricles and the mitral and tricuspid AVPD can evaluate the ventricular systolic interdependence and with these parameters we propose a classification with possible prognostic implications.

Acute right ventricular infarction: clinical spectrum, results of reperfusion therapy and short-term prognosis.

BACKGROUND: The role of thrombolytic therapy (TT) and percutaneous coronary interventions (PCIs) in subgroups of patients with right ventricular infarction (RVI) has not been evaluated. METHODS AND RESULTS: We risk-stratified 302 patients with RVI into three subsets upon admission. Class A (n=197) comprised patients without right ventricular (RV) failure, Class B (n=69) with RV failure and Class C (n=36) with cardiogenic shock. All eligible patients in Class A or B received either PCI or TT. Patients in Class C eligible for reperfusion were treated with PCI. All patients were evaluated for in-hospital major adverse cardiac events and short-term mortality. There was a statistically significant difference in in-hospital mortality among the classes. Classes B and C were the strongest indicators of in-hospital mortality. By multivariate analysis TT or PCI did not reduce mortality in Classes A and B, but a clinically favorable trend in mortality reduction was documented: both methods decreased RV dysfunction in Class B (from 97% to 61% with TT and to 28% with PCI; P < 0.001) and PCI reduced the risk of mortality in Class C (89.5% compared with 58%; P < 0.05). CONCLUSIONS: Classification into types A, B or C allows the prediction of mortality. The use of TT or PCI suggests a clinical favorable trend in the reduction of mortality in Class A, either is beneficial in Class B for decreasing morbidity and PCI appears to be the most appropriate procedure for Class C since it reduced mortality.

Análisis prospectivo multicéntrico de la clasificación descriptiva del electrocardiograma de ingreso y evolución en el infarto agudo de miocardio / Multicenter prospective analysis of a descriptive classification of ECG at admission and during evolution of the acute myocardial infarction

La clasificación descriptiva del electrocardiograma de ingreso está basada en los trastornos de la repolarización. Se correlacionó con el tipo de infarto evolutivo, Q y no Q y evolución clínica. Infarto Q: la mayoría deriva del ST elevado (96 por ciento), contrariamente a los infartos no Q que es un grupo heterogéneo, dado que su origen es variable: ST elevado (29,2 por ciento), infradesnivelado (36,3 por ciento), T negativas (20,4 por ciento), normal (2,7 por ciento) y otros (11,5 por ciento). Asimismo en los pacientes que ingresaron sin elevación del segmento ST, el análisis multivariado identificó dos variables independientes de riesgo clínico: edad mayor o igual 65 años y persistencia del segmento ST deprimido (infarto subendocárdico) (AU)

Valor terapéutico de la L-carnitina en la reducción del área necrótica en el infarto agudo del miocardio / Terapeutic value of L-carnitine in the reduction of the necrotic area in acute myocardial infarction

Introducción. Se han reportado defectos del metabolismo miocárdico en enfermedades cardiacas agudas y crónicas. Objetivo. Evaluar los efectos benéficos de la L-carnitina en la reducción del área de necrosis en el infarto agudo del miocardio. Pacientes y métodos. Estudiamos prospectivamente durante cinco días, 30 pacientes no trombolizados con infarto agudo del miocardio que ingresaron a una unidad de terapia intensiva (UTI): 20 pacientes (mujeres, 11 hombres, edad media de 54.6 ñ 2.5 años), grupo LC, recibieron tratamiento convencional más 50 mg/kg/día de L-carnitina IV, y 10 pacientes (cinco mujeres, cinco hombres, edad media de 55.7 ñ 1.6 años), grupo CN, sólo tratados con terapia convencional. El efecto protector de la L-carnitina sobre la cardiopatía isquemía se evaluó a través del decremento de los niveles plasmáticos de CK.MB, AST y LDH. Los datos se analizaron con la t de Student. Resultados. El pico máximo de CK-MB, AST y DHL fue 100.1 ñ 16.9, 46.7 ñ 2 y 147.6 ñ U/mL respectivamente en el grupo LC, y 184.5 ñ 29, 71.7 y 127.2 ñ 20.3 U/mL respectivamante también, en el grupo CN (p< 0.05). No se observaron efectos colaterales. Conclusión. La L-carnitina es útil en el manejo del infarto agudo del miocardio

Infartos con onda "q" e infartos con alteraciones en el segmento "ST-T" tambien denominados infartos sin onda "q", aclaración de conceptos y pronósticos

Con el objetivo de aclarar la diferencia entre los infartos con onda "q" y los que sólo tienen alteraciones en el "ST-T" (sin "q") revisamos 173 expedientes de pacientes fallecidos que tuvieron infarto del miocardio en el lapso de 13 años y a los cuales se les practicó necropsia, encontrándose sólo 18 pacientes que tuvieron infartos subendocárdicos "no q" clasificados por criterios anatómicos. Se analizaron los electrocardiogramas seriados y fueron observados en su evolución y se buscó la correlación electrocardiográfica de la extensión de la zona de necrosis comparado con los resultados de anatomía patológica. Además se separaron los pacientes que tenían oclusión subtotal de la arteria coronaria que irrigaba la zona infartada de los que tenían trombos sobreimpuestos en una placa ateromatosa vieja produciendo oclusión total, se analizaron las causas de muerte y se separaron los que fallecieron de causas no cardiogénicas. Se analizó la zona de necrosis representada en el electrocardiograma y la extensión informada por anatomía patológica, dividiéndose en IV grupos: Grupo I: Infartos subendocárdicos con "qR" en derivaciones inferiores. Grupo II: Con "QS" en V1 y V2, "qR" en V3. Grupo III: Pacientes con infartos subendocárdicos y alteraciones en "ST-T" en el electrocardiograma y Grupo IV: Infartos subendocárdicos sin onda "q" y trastornos enla conducción, demostrándose que la presencia o ausencia de onda "q" no permite diferenciar si el infarto es subendocárdico o es transmural anatomopatológicamente