Fatores que Impactam a Decisão de Realizar Ventriculografia Esquerda em Doença Arterial Coronariana / Factors That Impact the Decision to Perform Left Ventriculography in Coronary Artery Disease

Resumo Fundamento A ventriculografia esquerda é um método invasivo para avaliar a função sistólica do ventrículo esquerdo. Depois do advento de métodos não invasivos, o seu uso tem sido questionado por resultar em algum risco para o paciente. Objetivos Avaliar quais fatores associam-se independentemente com a decisão de realizar ventriculografia em pacientes com doença arterial coronariana. Métodos Tratou-se de um estudo analítico, retrospectivo, avaliando prontuários eletrônicos e banco de dados e comparando 21 variáveis de interesse pré-definidas entre pacientes submetidos a cineangiocoronariografia. Foi considerado significante p < 0,05. Resultados Avaliamos 600 pacientes consecutivos, e a ventriculografia esquerda foi realizada na maioria dos pacientes submetidos a uma cineangiocoronariografia (54%). Depois da análise multivariada, os pacientes com síndromes coronarianas crônicas ( odds ratio [OR] 1,72; intervalo de confiança de 95% [IC 95%]: 1,20-2,46; p < 0,01) tiveram maior chance de serem submetidos ao procedimento. Os pacientes com função ventricular conhecida (OR = 0,58; IC 95%: 0,40-0,85; p < 0,01), os revascularizados (OR 0,31; IC 95% 0,14-0,69; p < 0,01), os hipertensos (OR 0,58; IC 95%: 0,36-0,94; p = 0,02) e aqueles com maiores valores de creatinina (OR 0,42; IC 95% 0,26-0,69; p < 0,01) tiveram maior chance de não realizar ventriculografia. Conclusões Nos pacientes submetidos a cineangiocoronariografia, o diagnóstico de síndrome coronariana crônica associou-se de modo independente com uma maior realização da técnica, enquanto ter a função ventricular previamente conhecida, ser hipertenso, ter sido submetido a revascularização cirúrgica prévia e ter valores de creatinina mais elevados associaram-se a uma maior chance de não realizar o método.

Abstract Background Left ventriculography is an invasive method for assessment of left ventricular systolic function. Since the advent of noninvasive methods, its use has been questioned, as it carries some risk to the patient. Objective To assess which factors are independently associated with the decision to perform ventriculography in patients with coronary artery disease. Methods Analytical, retrospective, database review study of electronic medical records comparing 21 predefined variables of interest among patients undergoing coronary angiography. P-values <0.05 were considered significant. Results We evaluated 600 consecutive patients undergoing coronary angiography. Left ventriculography was performed in the majority of cases (54%). After multivariate analysis, patients with chronic coronary syndrome (OR 1.72; 95% CI: 1.20-2.46; p < 0.01) were more likely to undergo the procedure. Patients with known ventricular function (OR 0.58; 95% CI: 0.40-0.85; p < 0.01); those with a history of CABG (OR 0.31; 95% CI: 0.14-0.69; p < 0.01) or hypertension (OR 0.58; 95% CI: 0.36-0.94; p = 0.02); and those with higher creatinine levels (OR 0.42; 95% CI: 0.26-0.69; p < 0.01) had greater odds of not undergoing ventriculography. Conclusions In patients undergoing coronary angiography, a diagnosis of chronic coronary syndrome was independently associated with greater likelihood of left ventriculography, while having previously determined ventricular function, a history of hypertension or CABG, and higher creatinine levels were associated with a decreased likelihood of undergoing this procedure.

Comparison between Radionuclide Ventriculography and Echocardiography for Quantification of Left Ventricular Systolic Function in Rats Exposed to Doxorubicin / Comparação entre a Ventriculografia Radioisotópica e a Ecocardiografia na Quantificação da Função Sistólica Ventricular Esquerda em Ratos Expostos à Doxorrubicina

Abstract Background: Radionuclide ventriculography (RV) is a validated method to evaluate the left ventricular systolic function (LVSF) in small rodents. However, no prior study has compared the results of RV with those obtained by other imaging methods in this context. Objectives: To compare the results of LVSF obtained by RV and echocardiography (ECHO) in an experimental model of cardiotoxicity due to doxorubicin (DXR) in rats. Methods: Adult male Wistar rats serving as controls (n = 7) or receiving DXR (n = 22) in accumulated doses of 8, 12, and 16 mg/kg were evaluated with ECHO performed with a Sonos 5500 Philips equipment (12-MHz transducer) and RV obtained with an Orbiter-Siemens gamma camera using a pinhole collimator with a 4-mm aperture. Histopathological quantification of myocardial fibrosis was performed after euthanasia. Results: The control animals showed comparable results in the LVSF analysis obtained with ECHO and RV (83.5 ± 5% and 82.8 ± 2.8%, respectively, p > 0.05). The animals that received DXR presented lower LVSF values when compared with controls (p < 0.05); however, the LVSF values obtained by RV (60.6 ± 12.5%) were lower than those obtained by ECHO (71.8 ± 10.1%, p = 0.0004) in this group. An analysis of the correlation between the LVSF and myocardial fibrosis showed a moderate correlation when the LVSF was assessed by ECHO (r = -0.69, p = 0.0002) and a stronger correlation when it was assessed by RV (r = -0.79, p < 0.0001). On multiple regression analysis, only RV correlated independently with myocardial fibrosis. Conclusion: RV is an alternative method to assess the left ventricular function in small rodents in vivo. When compared with ECHO, RV showed a better correlation with the degree of myocardial injury in a model of DXR-induced cardiotoxicity.

Resumo Fundamento: A ventriculografia radioisotópica (VRI) é um método validado para avaliação da função sistólica do ventrículo esquerdo (FSVE) em pequenos roedores. Contudo, nenhum estudo prévio comparou os resultados obtidos com VRI com os obtidos por outros métodos de imagem neste contexto. Objetivos: Comparar os resultados de FSVE obtidos por VRI e por ecocardiografia (ECO) em modelo experimental de cardiotoxicidade por doxorrubicina (DXR) em ratos. Métodos: Ratos Wistar machos adultos controles (n = 7) e tratados com DXR (n = 22) em doses acumuladas de 8, 12 e 16 mg/kg, foram avaliados com ECO com equipamento Sonos 5500 Philips (transdutor de 12 MHz) e VRI adquirida em gama-câmara Orbiter-Siemens com colimador pinhole de 4 mm de abertura. Após eutanásia, foi realizada a quantificação histopatológica da fibrose miocárdica. Resultados: Os animais controles apresentaram valores comparáveis na análise da FSVE à ECO e à VRI (83,5 ± 5% e 82,8 ± 2,8%, respectivamente, p > 0,05). Os animais que receberam DXR apresentaram valores menores de FSVE quando comparados aos dos controles (p < 0,05); entretanto, observou-se neste grupo menores valores de FSVE obtidos por VRI (60,6 ± 12,5%) quando comparados aos obtidos pela ECO (71,8 ± 10,1%, p = 0,0004). A análise da correlação entre a FSVE e a fibrose miocárdica mostrou uma correlação moderada quando a FSVE foi estimada com a ECO (r = -0,69, p = 0,0002) e mais forte quando a FSVE foi obtida por VRI (r = -0,79, p < 0,0001). Apenas a VRI apresentou correlação de forma independente com a fibrose miocárdica à análise de regressão múltipla. Conclusão: A VRI é um método alternativo para avaliação da função ventricular esquerda in vivo em pequenos roedores, exibindo comparativamente à ECO melhor correlação com o grau de lesão miocárdica no modelo de cardiotoxicidade por DXR.

Generalización geométrica fractal de ventriculografías izquierdas normales y con disfunción leve / Fractal geometric generalization of normal left ventriculographies and with mild dysfunction

Introducción: la estructura cardiaca es por naturaleza, irregular, su adecuada caracterización se hace mediante la aplicación de la geometría fractal. Desde esta geometría se desarrolló un diagnóstico objetivo del ventriculograma izquierdo. Objetivo: desarrollar una generalización teórica de la dinámica ventricular izquierda en los estados de normalidad y enfermedad leve, a partir del diagnóstico matemático objetivo y reproducible desarrollado previamente. Se calcularon todas las posibles estructuras ventriculares durante la dinámica cardiaca a partir de los grados de similitud para casos que evolucionan entre normales y leves en busca de los prototipos matemáticos ventriculares de normalidad y enfermedad leve. Resultados: se estableció que la totalidad de posibles prototipos de la estructura ventricular para normalidad y enfermedad leve son 1345; 551 corresponden a normalidad y 794 a enfermedad leve. Al comparar los grados de similitud de ventrículos previamente medidos, con los prototipos obtenidos, se encontró que sus medidas estaban incluidas en la generalización. Conclusión: se desarrolló una nueva metodología de aplicación clínica reproducible y de ayuda diagnóstica objetiva, independiente de clasificaciones clínicas, con base en la generalización geométrica de la dinámica ventricular. (Acta Med Colomb 2014; 39: 131-136).

Introduction: Cardiac structure is irregular by nature; its proper characterization is done by application of fractal geometry. From this geometry an objective diagnosis of left ventriculogram was developed. Objective: to develop a theoretical generalization of left ventricular dynamics in states of normality and mild disease, from the objective and reproducible previously developed mathematical diagnosis. All possible ventricular structures were calculated during cardiac dynamics from the degrees of similarity for cases that evolve between normal and mild in search of mathematical prototypes of normality and mild disease. Results: It was established that all of the possible prototypes for normal ventricular structure and mild disease are 1345; 551 correspond to normality and 794 to mild disease. Comparing the degree of similarity of previously measured ventricles, with the obtained prototypes, it was found that its measures were included in the generalization. Conclusion: a new methodology for clinical application reproducible and of objective diagnostic aid independently of clinical classifications, based on the geometric generalization of ventricular dynamics, was developed. (Acta Med Colomb 2014; 39: 131-136).

Diagnóstico fractal del ventriculograma cardiaco izquierdo: geometría fractal del ventriculograma durante la dinámica cardiaca / Fractal diagnosis of left heart ventriculograms: fractal geometry of ventriculogram during cardiac dynamics

Antecedentes y objetivos: la geometría fractal permite describir y caracterizar los objetos irregulares, lo que resulta adecuado para medir estructuras del cuerpo humano. El propósito de este trabajo es caracterizar el ventrículo izquierdo durante la dinámica cardiaca con dimensiones fractales para desarrollar un diagnóstico matemático objetivo y reproducible de la ventriculografía izquierda. Método: este es un estudio de concordancia diagnóstica donde se calcularon las dimensiones fractales del ventrículo en sístole, en diástole y en un total de 36 ventriculogramas evaluados como normales, y anormales en leves, moderados y severos de acuerdo con la fracción de eyección según el diagnóstico clínico convencional; posteriormente se determinaron los grados de similitud de las dimensiones fractales entre los tres objetos componentes. Resultados: los grados de similitud estuvieron entre 1 y 9.000, y al organizar estos valores en conjuntos, se encontró una progresión a partir de los normales hasta los anormales severos. Se establecieron los grados de similitud característicos que permiten diferenciar normalidad de enfermedad y evolución entre éstas, evidenciando que la clasificación de la clínica convencional presenta dificultades al evaluar de forma precisa y objetiva la evolución de un ventriculograma hacia la normalidad o la enfermedad. Conclusiones: se desarrolló una nueva metodología diagnóstica objetiva y reproducible de aplicación clínica basada en evaluaciones geométricas independiente de la clasificación clínica.

Background and Objectives: fractal geometry allows to describe and characterize irregular objects, which is appropriate for measuring human body structures. The purpose of this study is to characterize the left ventricle during cardiac dynamics by means of fractal dimensions to develop an objective, mathematical and reproducible diagnosis of left ventriculography. Method: this is a diagnostic concordance study in which we calculated the fractal dimensions of the ventricle in systole, in diastole and in a total of 36 ventriculograms evaluated as normal, mild, moderate and severe according to the ejection fraction in accordance with the conventional clinical diagnosis ; subsequently, the degree of similarity of the fractal dimensions between the three components were determined. Results: the degrees of similarity were between 1 and 9,000, and when arranging these values into sets, there was a progression from normal to severe. We established the characteristic degrees of similarity that allow to distinguish normality from disease and the evolution between them, showing that the conventional clinical classification presents difficulties to assess accurately and objectively the evolution of a ventriculogram towards normality or disease. Conclusions: we developed a new objective and reproducible diagnostic methodology of clinical application based on geometric assessments that is independent from the clinical classification.

Enfermedad de Tako-Tsubo / The Tako-Tsubo disease

La enfermedad de “Tako-Tsubo”, conocida también como miocardiopatía de Tako-Tsubo o miocardiopatía por estrés, está caracterizada por dolor torácico, anormalidades del segmento ST-onda T en el ecosonograma, niveles séricos elevados de enzimas cardíacas y alteraciones en la motilidad del VI consistentes en acinesia apical extensa de carácter reversible. Describir las características clínicas y la experiencia del Centro Cardiovascular La Floresta en pacientes con miocardiopatía de Tako-Tsubo. Se realizó el diagnóstico de miocardiopatía de Tako-Tsubo en función de los criterios mayores y menores a pacientes ingresados a la sala de emergencia en el contexto de síndrome coronario agudo, sometidos a evaluación angiográfica, ecocardiográfica y egresados con seguimiento clínico y ecocardiográfico entre enero de 2006 a enero de 2008. De 288 pacientes 14 (5 %) cumplieron con criterios diagnósticos para miocardiopatía de Tako-Tsubo, todos refirieron estrés psicológico como desencadenante, cinco de estos 14 pacientes (36%), padecían de neoplasias malignas bajo tratamiento con quimioterapia, con edades promedio de 62 ± 12 años, de los cuales 9 (64%) fueron mujeres, todos con elevación de marcadores enzimáticos. Al ecosonograma presentaron alteraciones. En el ecocardiograma los pacientes tuvieron evidencia de acinesia apical y la fracción de eyección que estuvo por encima del límite inferior. Todos fueron sometidosa angiografía coronaria convencional y ventriculografía. La miocardiopatía de Tako-Tsubo es una entidad bien definida que imita a un síndrome coronario agudo. La estrategia diagnóstica está basada en la angiografía coronaria precoz sin omitir la ventriculografía. Especial interés debe ser puesto en pacientes con enfermedades neoplásicas que reciban quimioterapia.

Tako-Tsubo” disease, also known as apical ballooning of the left ventricle or stress cardiomyopathy, is characterized by resting chest pain, ST-T changes on the ECG, elevated cardiac biomarkers and reversible extensive apical akinesis which mimics, at end systole, a japanese jar used to trap octopodes called “Tako-Tsubo”. To describe our experience at the “Instituto Médico La Floresta” in patients with Tako-Tsubo disease. The diagnosis of Tako-Tsubo disease was made based on major and minor criteria to patients admitted to the emergency department with the diagnosis of acute coronary syndrome, between january 2006 and january 2008. All patients underwent cardiac catheterization, coronary angiography, left ventriculography and transthoracic echocardiography and were followed-up clinically and with echocardiography for 6 months. Of 288 patients, 14 (5%) met the criteria for Tako-Tsubo disease, all had emotional stress as a trigger, 5 of these 14 pts (36%) had malignancies on chemotherapy. The age range was 62±12 years, 9 patients (64%) were women, all with elevated CK and CK-MB and 7 (50%) had also increased troponin levels. On the ECG 11 patients (79%) had inverted T waves and 3 (21%) showed ST segment elevation. One patient (7%) developed non-sustained ventricular tachycardia. On the echocardiogram and left ventriculography all showed the typical pattern of Tako-Tsubo disease at end systole and none had neither evidence of left ventricular outflow tract obstruction nor coronary artery disease. Tako-Tsubo disease is a distinct entity which mimics an ACS. The suggested approach is an early diagnostic coronary angiography with left ventriculography. Patients with malignancies on chemotherapy deserve special attention.

Avaliação da reserva funcional miocárdica em portadores de aneurisma de ventrículo esquerdo por ventriculografia radioisotópica. Resposta ao exercício isotônico / Radionuclide Ventriculography Assessment of Myocardial Functional Reserve in Patients With Left Ventricular Aneurysm. Response to Isotonic Exercise

PURPOSE: To evaluate global and regional left ventricular (LV) ejection fractions (EF) by radionuclide ventriculography in patients with LV aneurysm at rest and during isotonic exercise. METHODS: Twenty patients were studied by radionuclide ventriculography at rest and during exercise. All patients had been submitted to cineangiography and showed LV aneurysm post myocardial infarction. RESULTS: Patients were divided according to LV EF in two groups: one with EF > or = 40 and the other with < 40 EF. Both groups showed normal response of global EF to exercise: mean rest EF was 40 +/- 14 and mean exercise EF was 45 +/- 14 (p < 0.01). When groups were considered separately, EF values showed the same behavior. Half of the patients showed normal response to exercise and the other half showed abnormal response. These changes were not associated with resting EF values, but were due to regional EF of lateral wall, that changed from 44 +/- 7 to 48 +/- 7 in the group of patients with normal LV EF response to stress and from 50 +/- 5 to 46 +/- 5 in those with abnormal response (p < 0.01). CONCLUSION: The evaluation of regional ventricular EF by radionuclide ventriculography during exercise better discriminates functional reserve in patients with LV aneurysm than resting global EF. These findings could help the decision making of the therapeutic approach in this specific group of patients.

Objetivo - Avaliar a fração de ejeção (FE) global e segmentar do ventrículo esquerdo (VE), em portadores de aneurisma ventricular pelo uso da ventriculografia radioisotópica no repouso e ao exercício isotônico. Métodos - Foram estudados 20 pacientes através da ventriculografia radioisotópica em repouso e na vigência de exercício isotônico. Os pacientes tinham dingnóstico de aneurisma de VE pós-infarto do miocárdio à cineangiografia contrastada. Resultados - Os pacientes foram divididos em 2 grupos segundo a FE global de VE no repouso: grupo com FE >40% e outro com FE <40%. Quando analisados os dois grupos em conjunto, a resposta da FE global ao esforço foi normal: média de FE no repouso 4014% e no esforço 4514% (p<0,01). Observou-se o mesmo comportamento das FE no esforço quando os 2 grupos foram analisados separadamente. Metade dos pacientes apresentou resposta normal da FE global de VE e na outra metade a resposta foi anormal. Este comportamento nao estava associado ao valor de repouso da FE global e deveu-se à resposta da FE regional da parede lateral ao exercício que passou de 447para 487% (p<0,01) no grupo com resposta normul e de 505 para 465% naqueles com resposta anormal (p<0,01). Conclusão - A avaliação da fração regional ventricular no esforço pela ventriculografia radioisotópica discrimina melhor a reserva funcional de portadores de aneurisma de VE do que a FE global de repouso e pode auxiliar na decisão terapêutica deste grupo de pacientes

Cineventriculografia com radionuclídeos e dipiridamol venoso na avaliaçäo prognóstica após infarto agudo do miocárdio / Dipyridamole­radionuclide ventriculography in the prediction offuture cardiac events after acute myocardial infarction.

Avaliar a cineventriculografia com radionuclídeos (VGR) e dipiridamol venoso (VGR-D) na previsäo de futuros eventos cardíacos após infarto do miocárdio (IAM). Casuística e Métodos - Quarenta e um pacientes (37 homens) com IAM submetidos a VGR em repouso e VGR-D (0,58 mg/Kg de peso) venoso. Considerou-se positivo para isquemia a incapacidade em elevar a fraçäo de ejeçäo do ventrículo esquerdo em 0,05 do valor basal. Todos os pacientes foram ainda submetidos a cinecoronariografia e, em 36 casos, foi realizada cintigrafia com tálio-201 para comparaçäo. O acompanhamento médico foi de 16 ñ 3 meses, sendo definido como evento cardíaco futuro as ocorrências de morte de origem cardíaca, reinfarto do miocárdio, angina ou insuficiência cardíaca significativas. Resultados - Vinte (50%) pacientes apresentaram eventos cardíacos durante a evoluçäo. Destes 90% tinham VGR-D positiva, enquanto que dentre os livres de eventos, VGR-D foi positiva em 24% (p < 0,01). Entre os parâmetros ventriculográficos estudados, o tipo de reposta da fraçäo de ejeçäo do ventrículo esquerdo ao dipiridamol, bem como seus valores absolutos apresentaram os mais significativos resultados da previsäo de futuros eventos (p < 0,01 e p < 0,001). Dos 36 pacientes submetidos também a cintigrafia de perfusäo, 16 subseqüentemente evoluíram com eventos, dentre os quais a cintigrafia era positiva em 82% (p < 0,01). Näo houve complicaçöes fatais, embora 12 (29%) pacientes tenham apresentado reaçöes isquêmicas clínicas durante o teste. Conclusäo - VGR-D mostrou-se sensível na previsäo de eventos cardíacos futuros após IAM, embora experiência adicional seja necessária antes de recomendá-la rotineiramente

Purpose ­ To evaluate safety and usefulness of dipyridarrtole-radionuclide ventriculography (D-RVG), soon after acute myocardial infarction (MI), in the prediction of future cardiac events. Traditionally performed tests were also compared. Patients and Methods ­ Forty-one patients (4 females) with recent MI underwent rest and dipyridamole (0,58 mg/kg of body weight) radionuclide ventriculography. The criteria for a positive test for ischemia was failure to increase left ventricular ejection fraction in 0,05 from baseline value. All patients had also coronary angiography and 36 patients underwent thallium-201 scintigraphy for comparison. The mean follow-up was 16 ± 3 months. The following findings were considered future for events: cardiac death, reinfarction, significant angina or heartfailure. Results ­ During the follow-up 18 of the 20 patients who had cardiac events had shown positive dipyridamole-RVG, as opposed to 5 of 21 event-free patients (p < 0,01). The ventriculographic criteria for a positive test and dipyridamole left ventricular ejection fraction were the strongest predictors of those medical events (p < 0,01 and p < 0,001). Among the 36 patients who had thallium-201 imaging, 16 subsequently had cardiac events and the scans were positive in 82% (p < 0,01). Twelve (29%) patients experienced reactions during dipyridamole infusion although no fatal complications were noted. Conclusion ­ Dipyridamole-RVG is relatively safe and a sensitive predictor of future cardiac events soon after acute MI, although additional experience is required before this new technique should be routinely recommended as an alternative approach.