Prognostic Factors in Severe Chagasic Heart Failure / Fatores Prognósticos na Insuficiência Cardíaca Grave de Etiologia Chagásica

Abstract Background: Prognostic factors are extensively studied in heart failure; however, their role in severe Chagasic heart failure have not been established. Objectives: To identify the association of clinical and laboratory factors with the prognosis of severe Chagasic heart failure, as well as the association of these factors with mortality and survival in a 7.5-year follow-up. Methods: 60 patients with severe Chagasic heart failure were evaluated regarding the following variables: age, blood pressure, ejection fraction, serum sodium, creatinine, 6-minute walk test, non-sustained ventricular tachycardia, QRS width, indexed left atrial volume, and functional class. Results: 53 (88.3%) patients died during follow-up, and 7 (11.7%) remained alive. Cumulative overall survival probability was approximately 11%. Non-sustained ventricular tachycardia (HR = 2.11; 95% CI: 1.04 - 4.31; p<0.05) and indexed left atrial volume ≥ 72 mL/m2 (HR = 3.51; 95% CI: 1.63 - 7.52; p<0.05) were the only variables that remained as independent predictors of mortality. Conclusions: The presence of non-sustained ventricular tachycardia on Holter and indexed left atrial volume > 72 mL/m2 are independent predictors of mortality in severe Chagasic heart failure, with cumulative survival probability of only 11% in 7.5 years.

Resumo Fundamento: Fatores prognósticos são bastante estudados na insuficiência cardíaca (IC), mas ainda não possuem um papel estabelecido na IC grave de etiologia chagásica. Objetivo: Identificar a associação de fatores clínicos e laboratoriais com o prognóstico da IC grave de etiologia chagásica, bem como a associação desses fatores com a taxa de mortalidade e a sobrevida em um seguimento de 7,5 anos. Métodos: 60 pacientes portadores de IC grave de etiologia chagásica foram avaliados com relação às seguintes variáveis: idade, pressão arterial, fração de ejeção, sódio plasmático, creatinina, teste de caminhada de 6 minutos, taquicardia ventricular não sustentada, largura do QRS, volume do átrio esquerdo indexado e classe funcional. Resultados: 53 (88,3%) pacientes foram a óbito durante o período de seguimento e 7 (11,7%) permaneceram vivos. A probabilidade de sobrevida geral acumulada foi de aproximadamente 11%. Taquicardia ventricular não sustentada (HR = 2,11; IC 95%: 1,04 - 4,31; p<0,05) e volume do átrio esquerdo indexado ≥ 72 ml/m2 (HR = 3,51; IC 95%: 1,63 - 7,52; p<0,05) foram as únicas variáveis que permaneceram como preditores independentes de mortalidade. Conclusão: A presença de taquicardia ventricular não sustentada ao Holter e o volume do átrio esquerdo indexado > 72 ml/m2 são preditores independentes de mortalidade na IC chagásica grave, com probabilidade de sobrevida acumulada de apenas 11% em 7,5 anos.

Left Atrial Volume Determinants in Patients with Non-Ischemic Dilated Cardiomyopathy / Determinantes do Volume do Átrio Esquerdo em Pacientes com Cardiomiopatia Dilatada Não Isquêmica

Left atrial volume (LAV) is a predictor of prognosis in patients with heart failure.

O Volume do Átrio Esquerdo (VAE) é preditor prognóstico em pacientes com insuficiência cardíaca.

Resultados a largo plazo del trasplante intracoronario de células mononucleares de médula ósea autólogas en pacientes con cardiopatía dilatada de diversa etiología / Long-term results of intracoronary transplantation of autologous bone marrow cells in dilated cardiomyopathy

Background: Intracoronary delivery of autologous bone marrow mononuclear cells is an interesting therapeutic promise for patients with heart failure of different etiologies. Aim: To evaluate the long-term safety and efficacy of this therapy in patients with dilated cardiomyopathy of different etiologies under optimal medical treatment. Patients and Methods: Prospective, open-label, controlled clinical trial. Of 23 consecutive patients, 12 were assigned to autologous bone marrow mononuclear cell intracoronary transplantation, receiving a mean dose of 8.19 ± 4.43 x 10(6) CD34+ cells. Mortality, cardiovascular readmissions and cancer incidence rate, changes in functional capacity, quality of life questionnaires and echocardiographic measures from baseline, were assessed at long-term follow-up (37.7 ± 9.7 months) in patients receiving or not the cells. Results: No significant differences were observed in mortality, cardiovascular readmissions or cancer incidence rate amongst groups. An improvement in functional class and quality of life questionnaires in the transplanted group was observed (p < 0.01). The treated group showed a non-significant increase in left ventricular ejection fraction at long-term follow-up (from 26.75 ± 4.85% to 34.90 ± 8.57%, p = 0.059 compared to baseline). There were no changes in left ventricular volumes. We observed no improvement of these variables in the control group. Conclusions: Intracoronary transplantation of autologous bone marrow mononuclear cells is feasible and safe in patients with dilated cardiomyopathy of diverse etiologies. This therapy was associated to persistent improvements in functional class and quality of life. There was also a non-significant long-term improvement of left ventricular function.

Left Atrial Volume Index and Prediction of Events in Acute Coronary Syndrome: Solar Registry / Índice de Volume Atrial Esquerdo e Predição de Eventos em Síndrome Coronária Aguda: Registro Solar

Background: According to some international studies, patients with acute coronary syndrome (ACS) and increased left atrial volume index (LAVI) have worse long-term prognosis. However, national Brazilian studies confirming this prediction are still lacking. Objective: To evaluate LAVI as a predictor of major cardiovascular events (MCE) in patients with ACS during a 365-day follow-up. Methods: Prospective cohort of 171 patients diagnosed with ACS whose LAVI was calculated within 48 hours after hospital admission. According to LAVI, two groups were categorized: normal LAVI (≤ 32 mL/m2) and increased LAVI (> 32 mL/m2). Both groups were compared regarding clinical and echocardiographic characteristics, in- and out-of-hospital outcomes, and occurrence of ECM in up to 365 days. Results: Increased LAVI was observed in 78 patients (45%), and was associated with older age, higher body mass index, hypertension, history of myocardial infarction and previous angioplasty, and lower creatinine clearance and ejection fraction. During hospitalization, acute pulmonary edema was more frequent in patients with increased LAVI (14.1% vs. 4.3%, p = 0.024). After discharge, the occurrence of combined outcome for MCE was higher (p = 0.001) in the group with increased LAVI (26%) as compared to the normal LAVI group (7%) [RR (95% CI) = 3.46 (1.54-7.73) vs. 0.80 (0.69-0.92)]. After Cox regression, increased LAVI increased the probability of MCE (HR = 3.08, 95% CI = 1.28-7.40, p = 0.012). Conclusion: Increased LAVI is an important predictor of MCE in a one-year follow-up. .

Fundamento: Portadores de síndrome coronária aguda (SCA) com aumento do índice de volume atrial esquerdo (IVAE) apresentam pior prognóstico em longo prazo segundo alguns estudos internacionais. Todavia, há carência de estudos nacionais ratificando esta predição. Objetivo: Avaliar o IVAE como preditor de evento cardiovascular maior (ECM) em seguimento tardio de pacientes com SCA. Métodos: Coorte prospectiva de 171 pacientes com diagnóstico de SCA e com IVAE calculado dentro de 48 horas após evento índice. Portadores de IVAE normal (≤ 32 ml/m2) e de IVAE aumentado (> 32 ml/m2) foram comparados quanto às características clínicas e ecocardiográficas, evolução intra e extra-hospitalar e ocorrência, em até 365 dias, de ECM. Resultados: Um total de 78 pacientes (45%) apresentaram IVAE > 32 ml/m2. Ocorreu associação entre IVAE aumentado e maior idade, índice de massa corpórea, hipertensão arterial, história de infarto agudo do miocárdio e angioplastia prévia, assim como menor clearance de creatinina e fração de ejeção. Na evolução hospitalar, o edema agudo de pulmão foi mais frequente em pacientes com IVAE aumentado (14,1% vs. 4,3%, p = 0,024). Após a alta hospitalar, a ocorrência do desfecho composto para ECM foi significativamente superior (p = 0,001) no grupo com IVAE aumentado (26%) quando comparado ao grupo de IVAE normal (7%) [RR (IC 95%) = 3,46 (1,54-7,73) vs. 0,80 (0,69-0,92)]. Na regressão de Cox, IVAE aumentado elevou a probabilidade de ECM (HR = 3,08; IC 95% = 1,28-7,40; p = 0,012). Conclusão: O aumento do IVAE é importante preditor de ECM em um ano de seguimento. .

Fração de ejeção e volumes do ventrículo esquerdo medidos com eco 3D e com tomografia ultra-rápida / Fracción de eyección y volúmenes del ventrículo izquierdo medidos con eco- 3DTR y con tomografía ultrarrápida / Left ventricular ejection fraction and volumes as measured by 3d echocardiography and ultrafast computed tomography

FUNDAMENTO: O ecocardiograma tridimensional em tempo real (ECO 3D) e a tomografia computadorizada ultra-rápida (CT) são dois novos métodos de análise da fração de ejeção e dos volumes do VE. OBJETIVO: Comparar as medidas da FEVE e dos volumes do VE aferidos pelo ECO 3D e pela CT ultra-rápida. MÉTODOS: Foram estudados pelo ECO 3D e pela CT ultra-rápida de 64 cortes, 39 pacientes consecutivos (27 homens, média etária de 57±12 anos). Foram analisados: FEVE e volumes do VE. Análise estatística: coeficiente de correlação (r: Pearson), teste de Bland & Altman, teste de regressão linear, 95 por cento IC, p<0,05. RESULTADOS: Medidas do ECO 3D: a FEVE variou de 56,1 a 78,6 (65,5±5,58) por cento; volume diastólico final variou de 49,6 a 178,2 (87±27,8)ml; volume sistólico final variou de 11,4 a 78 (33,1±13,6)ml. Medidas da CT: a FEVE variou de 53 a 86 (67,8±7,78) por cento; volume diastólico final variou de 51 a 186 (106,5±30,3) ml; volume sistólico final variou de 7 a 72 (35,5±13,4)ml. As correlações entre ECO 3D e CT foram: FEVE (r: 0,7888, p<0,0001, 95 por cento IC 0,6301 a 0,8843); volume diastólico final (r: 0,7695, p<0,0001, 95 por cento IC 0,5995 a 0,8730); volume sistólico final (r: 0,8119, p<0,0001, 95 por cento IC 0,6673 a 0,8975). CONCLUSÃO: Nesta série, foi observada boa correlação entre as medidas da FEVE e entre os volumes ventriculares aferidos pelo ECO3D e pela CT ultra-rápida de 64 cortes.

BACKGROUND: Real-time three-dimensional echocargiography (RT-3D-Echo) and ultrafast computed tomography (CT) are two novel methods for the analysis of LV ejection fraction and volumes. OBJECTIVE: To compare LVEF and volume measurements as obtained using RT-3D-Echo and ultrafast CT. METHODS: Thirty nine consecutive patients (27 men, mean age of 57±12 years) were studied using RT-3D-Echo and 64-slice ultrafast CT. LVEF and LV volumes were analyzed. Statistical analysis: coefficient of correlation (r: Pearson), Bland-Altman analysis, linear regression analysis, 95 percent CI, p<0.05. RESULTS: RT-3D-Echo measurements: LVEF ranged from 56.1 to 78.6 (65.5±5.58) percent; end-diastolic volume ranged from 49.6 to 178.2 (87±27.8) ml; end-systolic volume ranged from 11.4 to 78 (33.1±13.6) ml. CT scan measurements: LVEF ranged from 53 to 86 percent (67.8±7.78); end-diastolic volume ranged from 51 to 186 (106.5±30.3) ml; end-systolic volume ranged from 7 to 72 (35.5±13.4)ml. Correlations between RT-3D-Echo and CT were: LVEF (r: 0.7888, p<0.0001, 95 percent CI 0.6301 to 0.8843); end-diastolic volume (r: 0.7695, p<0.0001, 95 percent CI 0.5995 to 0.8730); end-systolic volume (r: 0.8119, p<0.0001, 95 percent CI 0.6673 to 0.8975). CONCLUSION: Good correlation between LVEF and ventricular volume parameters as measured by RT-3D-Echo and 64-slice ultrafast CT was found in the present case series.

FUNDAMENTO: La ecocardiografía tridimensional en tiempo real (Eco-3DTR) y la tomografía computarizada ultrarrápida (TC ultrarrápida) son dos nuevos métodos de análisis de la fracción de eyección (FE) y de los volúmenes del ventrículo izquierdo (VI). OBJETIVO: Comparar las mediciones de la fracción de eyección del ventrículo izquierdo (FEVI) y de los volúmenes del VI apurados por la Eco-3DTR y por la TC ultrarrápida. MÉTODOS: Se estudiaron, mediante la Eco-3DTR y la TC ultrarrápida de 64 cortes, a 39 pacientes consecutivos (27 varones, promedio de edad de 57±12 años). Se analizaron: FEVI y volúmenes del VI. Análisis estadístico: coeficiente de correlación (r: Pearson), prueba de Bland & Altman, prueba de regresión lineal, 95 por ciento IC, p<0,05. RESULTADOS: Valores de la Eco-3DTR: variación de la FEVI de 56,1 a 78,6 (65,5±5,58) por ciento; variación del volumen diastólico final de 49,6 a 178,2 (87±27,8)mL; variación del volumen sistólico final de 11,4 a 78 (33,1±13,6)mL. Valores de la TC ultrarrápida: variación de la FEVI de 53 a 86 (67,8±7,78) por ciento; variación del volumen diastólico final de 51 a 186 (106,5±30,3) mL; variación del volumen sistólico final de 7 a 72 (35,5±13,4) mL. Las correlaciones entre la Eco-3DTR y la TC ultrarrápida fueron: FEVI (r: 0,7888, p<0,0001, 95 por ciento IC 0,6301 a 0,8843); volumen diastólico final (r: 0,7695, p<0,0001, 95 por ciento IC 0,5995 a 0,8730); volumen sistólico final (r: 0,8119, p<0,0001, 95 por ciento IC 0,6673 a 0,8975). CONCLUSIÓN: En esta serie, se observó una buena correlación entre las mediciones de la FEVI y entre los volúmenes ventriculares apurados por la Eco-3DTR y por la TC ultrarrápida de 64 cortes.

Valor prognóstico do índice do volume do átrio esquerdo em pacientes em hemodiálise / Prognostic value of left atrial volume index in hemodialysis patients

OBJETIVO: Avaliar o valor prognóstico do índice do volume do átrio esquerdo (IVAE) no curso clínico dos pacientes de hemodiálise (HD), comparando com parâmetros clínicos e ecocardiográficos previamente estabelecidos. MÉTODOS: Foram realizadas ecocardiografias em 118 pacientes de HD, que foram acompanhados por 19 ± 8 meses. O desfecho pesquisado foi composto de mortalidade geral e eventos cardiovasculares não-fatais. O valor prognóstico independente do IVAE foi testado pela análise multivariada de Cox. RESULTADOS: O IVAE e outros parâmetros clínicos e ecocardiográficos foram preditores do prognóstico na análise univariada. Na análise multivariada, o IVAE foi preditor independente do prognóstico (hazard ratio, 1,03 por ml/ m²; intervalo de confiança de 95 por cento, 1,01 a 1,05; p=0,014) e adicionou informação incremental ao modelo contendo preditores tradicionais de risco cardiovascular, como massa ventricular esquerda, fração de ejeção e variáveis clínicas (p=0,02). CONCLUSÃO: O IVAE é preditor independente do prognóstico em pacientes de HD, provendo informação incremental aos dados clínicos e Doppler ecocardiográficos tradicionais.

OBJECTIVE: To evaluate the prognostic value of left atrial volume index (LAVi) in the clinical course of hemodialysis (HD) patients, compared with previously established echocardiographic and clinical parameters. METHODS: Echocardiograms were obtained from 118 hemodialysis patients, who were then followed for 19 ± 8 months. Study endpoint was a composite of all-cause mortality and nonfatal cardiovascular events. Cox multivariate analysis was used do assess the independent prognostic value of LAVi. RESULTS: On univariate analysis, LAVi and other clinical and echocardiographic parameters were predictive of prognosis. Multivariate analyses showed that LAVi was an independent predictor of prognosis (hazard ratio 1.03 per ml/m², 95 percent confidence interval: 1.01 to 1.05, p=0.014), and added incremental information to the model containing traditional predictors of cardiovascular risk, such as left ventricular mass, ejection fraction, and clinical variables (p=0.02). CONCLUSION: LAVi is an independent predictor of prognosis in HD patients, providing incremental information to traditional clinical and Doppler echocardiographic data.

Remodelação miocárdica na sobrecarga crônica de pressão ou de volume no coração de ratos / Myocardial remodeling in chronic pressure or volume overload in the rat heart

OBJETIVO: Comparar as alterações estruturais cardíacas em modelos experimentais de sobrecarga de pressão e de volume. MÉTODOS: Foram analisados ratos com hipertensão renovascular (HRV, n = 8), normotensos com sobrecarga de volume por fístula aortocava (FAV, n = 10) e animais controles (CONT, n = 8). Após quatro semanas, registrou-se a pressão arterial caudal (PAS) e obtiveram-se os pesos dos ventrículos direito (PVD) e esquerdo (PVE). Em cortes histológicos, foram medidas as áreas seccionais dos miócitos (AM), a espessura da parede do VE (E), o diâmetro da cavidade (DVE), a relação E/DVE, e a fração de colágeno (CVF). As comparações foram feitas pela ANOVA e teste de Tukey para nível de significância de 5 por cento. RESULTADOS: A PAS (mmHg) foi maior no grupo HRV (HRV = 187 ± 22; CONT = 125 ± 10; FAV = 122 ± 6, p < 0,05). A hipertrofia do VE foi observada nos grupos HRV e FAV. O grupo FAV apresentou aumento significante do DVE, comparado ao CONT e HRV. As espessuras absoluta e normalizada da parede ventricular foram semelhantes entre os grupos. Houve aumento significante do CVF no grupo HRV em relação aos grupos CONT e FAV. CONCLUSÃO: A sobrecarga de volume causa padrão distinto de remodelação cardíaca, quando comparada com aquela decorrente da hipertensão arterial, sugerindo que as implicações funcionais de cada padrão não são intercambiáveis.

Analisis ecocardiografico del efecto de diferentes inhibidores del intercambiador Na+/H+ sobre la estructura y funcion sistolica del ventriculo izquierdo en ratas espontaneamente hipertensas / Echocardiographic analysis of the effect of different Na+/H+ exchanger inhibitors on left

El presente estudio fue proyectado para analizar mediante ecocardiograma los efectos del HOE 642 (cariporide) (HOE) y del BIIB 723 (BIIB) sobre la estructura y función sistólica del ventrículo izquierdo en ratas espontáneamente hipertensas (SHR)- 8 con 30 mg/kg/día de HOE, 8 con 30 mg/kg/día de BIIB durante 30 días y 4 sin tratamiento (grupo control) durante esos 30 días. Los distintos parámetros analizados no mostraron cambios durante ese período en las ratas controles. Si bien el HOE determinó un leve descenso de la presión arterial (C: 184 ± 1.75 mm Hg; 30d:176.20 ± 2.60 mm Hg, p <0.01), no detectada con BIIB,ambas drogas provocaron un aumento del estrés sistólico pico (HOE C:166 ± 29 kdinas/cm2; 30d: 204 ± 34kdinas/cm2, p <0.04. BIIB C: 164 ± 25.90 kdinas/cm2; 30d: 234 ± 29.30 kdinas/cm2, p<0.02).Tanto HOE comoBIIB redujeron significativamente la masa ventricular izquierda (MVI) (HOE C: 612.50±50 mg; 30d:452 ± 37 mg,p <0.01; BIIB C: 544 ± 16mg; 30 d: 374 ± 25 mg, p<0.01). El porcentaje de acortamiento endocárdico no semodificó luego del tratamiento con HOE (C: 62.30 ± 2.75; 30d 65.50 ± 2.40%, ns) y BIIB (C: 63.20 ± 2.39%;30d 67.20 ± 1.62%, ns). Los resultados analizados permiten concluir que ambos inhibidores determinaron similarreducción de la MVI. Esa reducción se acompañó de mejoría en los índices de evaluación de la función sistólica ventricular izquierda, pese al incremento del estrés sistólico pico. Estas evidencias sugieren que independientemente del inhibidor utilizado se encuentra un aumento del inotropismo, previamente comprometidodurante el desarrollo de la hipertrofia

The aim of this study was to analyze by echocardiogram, the action of two Na+/H+ exchange, inhibitors, HOE 642 (HOE) and BIIB 723 (BIIB) on left ventricular (LV) mass and LV systolic function. We studied 16 spontaneously hypertensive rats (SHR), 8 treated with HOE 30 mg/kg/day, 8 with 30 mg/kg/day of BIIB during 30 days and 4 SHR as controls during those 30 days. Results are expressed as mean values ± SEM. The systolic blood pressure and theechocardiograpic parameters examined did not evidence changes during that period in the controls rats. Eventhough HOE determined a slight decrease in blood pressure (HOE C: 184 ± 1.75 mm Hg; HOE 30d: 176.20 ±2.60 mm Hg - p <0.01) which was not detected with BIIB, both drugs provoked an increase of peak systolic stress (HOE C: 166 ± 29 kdynes/cm2; HOE 30d: 204 ± 34 kdynes/cm2, p <0.04; BIIB C: 164 ± 25.90 kdynes/cm2; BIIB 30d: 234 ± 29.30 kdynes/cm2, p <0.02). HOE and BIIB reduced LV mass after 30 days of administration (HOE C: 612.50 ± 50 mg; 30d: 452 ± 37 mg, p <0.01. BIIB C: 544 ± 16mg; 30d: 374 ± 25 mg, p <0.01). LV endocardial shortening was similar independently of the NHE inhibitors used (HOE C: 62.30 ± 2.75%; 30d: 65.50 ± 2.40%, ns. BIIB C: 63.20 ± 2,39%; 30d 67,20 ± 1.62%, ns). These data demonstrate that long-treatment with HOE or BIIB produced similar LV mass regression without changes in endocardial fractional shortening in spite of the increase of peak systolic stress. This finding could represent an increased inotropism previously depressed by the development of hypertrophy

Demonstracão do mecanismo da terapia de ressincronizacão ventricular com ecocardiografia tridimensional em tempo real em paciente com insuficiência cardíaca / Mechanism of cardiac resynchronization therapy by real-time three-dimensional echocardiography in patients with heart failure

Relatamos caso de homem de 66 anos de idade portador de insuficiência cardíaca classe funcional (NYHA) IV que foi submetido a terapia de ressincronizacão cardíaca por implante de marcapasso biventricular. O paciente foi avaliado antes e 48 horas após o implante do marcapasso com o emprego da ecocardiografia tridimensional transtorácica em tempo real. A utilizacão da ecocardiografia tridimensional contribuiu para o entendimento do mecanismo envolvido na ressincronizacão cardíaca através da demonstracão da melhor sincronizacão dos segmentos cardíacos, o que resultou em melhora clínica do paciente.

Left Ventricle Myocardium Volume Densities in Spontaneously Hypertensive Rats (SHR) Following Combination of Exercise and ACE Inhibitor Treatment: A Stereological Study / Densidad de Volumen del Miocardio del Ventrículo Izquierdo en Ratas Espontáneamente Hipertensas (REH) Posterior a la Combinación de Ejercicios y Tratamiento Inhibidor de la ACE: Estudio Estereológico

This study was designed to test the possible effects of a combination of physical and pharmacological therapy intervention on myocardial structure of the left ventricle in spontaneously hypertensive rats (SHR). Twelve weeks old spontaneously hypertensive rats (n = 40) were divided into four groups of sedentary, (Sed) as controls, exercise only (Exer), lisinopril only 20mg/kg/day (Lis), and exercise + lisinopril (LisExer). Exercise training was performed on a treadmill (5m/min.) for 60 minutes/day, 5 days/week for 10 weeks. At the end of 10 weeks, all the rats were terminally anaesthetised, the heart was arrested in diastole by intravenous procaine and whole animal perfusion fixation through the abdominal aorta was carried out using Karnovsky's fixative (pH 7.24). The heart was removed and left ventricle plus the interventricular septum was serially sectioned at a thickness of 3 mm. One piece was randomly chosen, and embedded in JB4 resin. Six sections were obtained from each block, stained with toluidine blue:acid fucin. Measurement of volume fraction (Vf), of myocardium, capillaries and interstitium were carried out using a stereology software (Histometrix MIL6 Kinetic imaging Ltd.). Mean Vf of capillaries in Sed group was 0.114 ± 0.01 (SEM). This was significantly increased in LisExer group. The Vf of muscle in Sed group was 0.795 ± 0.02 (SEM). This was significantly decreased in Lis but unchanged in Exer group. Capillaries Vf was significantly higher in LisExer as compared to Lis or Exer groups (p<0.05). Muscle Vf was not different betweenLisExer and Lis groups. The outcome of these changes could well be a better enhancement of cardiac performance in hypertension by combined exercise and ACE inhibitor treatment than either of the interventions alone.

Este estudio fue diseñado para probar los posibles efectos de una combinación de ejercicios y una intervención de terapia farmacológica en las estructuras del miocardio del ventrículo izquierdo, en ratas espontaneamente hipertensivas (SHR). Ratas de 20 semanas espontáneamente hipertensas (n = 40) fueron divididas en cuatro grupos: sedentarias (Sed) y controles, solamente con ejercicio (Ejer), solamente con lisinopril con 20mg/kg/día (Lis), y ejercicios + lisinopril (LisEjer). Los ejercicios fueron ejecutados en una máquina de entrenamiento (5m/min.) por 60 minutos/día, 5 días/semana por 10 semanas. Al término de las 10 semanas, las ratas fueron sacrificadas bajo anestesia, el corazón fue detenido en diástole usando procaina intravenosa. Los animales fueron perfundidos a través de la parte abdominal de la aorta, usando solución de Karnovsky (pH 7.24). El corazón fue removido y tanto al ventrículo izquierdo como al septo interventricular se les realizaron cortes seriados de 3 µm. Una pieza fue seleccionados al azar, y sumergida en resina JB4. Fueron obtenidas 6 secciones de cada bloque y luego teñidas con azul de toluidina:fucsina ácida. Las mediciones de fracción volumétrica (Vf) del miocardio, capilares, e intersticio fueron obtenidas usando un software de estereología (Histometrix MIL6 Kinetic imaging Ltd.). El promedio Vf de capilares en el grupo Sed, fue 0.114 ± 0.01 (SEM). Éste fue significativamente mayor en el grupo LisExer. El Vf de músculo en Sed fue 0.795 ± 0.02 (SEM). Éste fue significativamente menor en Lis pero no varió en el grupo Ejer. Vf capilares fue significativamente alto en LisExjr, si es comparado con los grupos Lis o Ejer (p<0.05). En Vf músculo no hubo diferencias entre los grupos LisEjer y Lis. El resultado de estos cambios pudo deberse a un mejor funcionamiento cardiaco en ratas hipertensa,s producto de ejercicios combinados y tratamiento con inhibidor ACE, que en aquellos en que se efectó un solo procedimiento.

Evaluation of functional parameters and left ventricular size by radionuclide ventriculography (RNV) in myocardial infarction patients.

Functional parameters like left ventricular ejection fraction (LVEF), peak ejection rate (PER), peak filling rate (PFR), regional wall motion and left ventricular size index were evaluated in 68 patients with myocardial infarction and in 50 normal subjects, by radionuclide ventriculography (RNV). Patients were divided into four groups (I to IV) according to increasing left ventricular size and the parameters were evaluated in each group. LVEF proved to be the most sensitive parameter of overall left ventricular performance. PFR decreased significantly from group I to group III but not from group III to group IV, suggesting that in extreme degrees of left ventricular enlargement some compensatory mechanism acts to prevent a greater fall in left ventricular compliance. LV size and performance were least affected in inferior wall myocardial infarction. LVEF was however a better predictor of LV size than the site of the myocardial infarction.

An evaluation of cardiac function in malnourished children by non-invasive methods.

Forty-six malnourished children between 3-48 mo with varying grades of malnutrition (PEM) were evaluated for left ventricular function by echocardiography. None of these children had any pre-existing cardiac disease, chronic illness or significant anemia. Children with Grades III and IV PEM had significantly smaller cardiac chamber size and ventricular wall thickness as compared to normally nourished children. Cardiac output as well as other indices of left ventricular function (percentage fractional shortening, mean rate of circumferential fibre shortening and ejection fraction) were also significantly decreased in severe PEM. The atrophic PEM heart does appear to show left ventricular dysfunction in moderately severe malnutrition.