The world health organization has identified cardiovascular disease as the leading cause of non-accidental deaths in the world. The heart is identified as diseased when it is not operating at peak efficiency. Early diagnosis of heart disease can impact treatment and improve a patient's outcome. An early sign of a diseased heart is a reduction in its pumping ability, which can be measured by performing functional evaluations. These are typically focused on the ability of the ventricles to pump blood to the lungs (right ventricle) or to the rest of the body (left ventricle). Non-invasive imaging modalities such as cardiac magnetic resonance have allowed the use of quantitative methods for ventricular functional evaluation. The evaluation still requires the tracing of the ventricles in the end-diastolic and end-systolic phases. Even though manual tracing is still considered the gold standard, it is prone to intra- and inter-observer variability and is time consuming. Therefore, substantial research work has been focused on the development of semi- and fully automated ventricle segmentation algorithms. In 2009 a medical imaging conference issued a challenge for short-axis left ventricle segmentation. A semi-automated technique using polar dynamic programming generated results that were within human variability. This is because a path in a polar coordinate system yields a circular object in the Cartesian grid and the left ventricle can be approximated as a circular object. In 2012 there was a right ventricle segmentation challenge, but no polar dynamic programming algorithms were proposed. One reason may be that polar dynamic programming can only segment circular shapes. To use polar dynamic programming for the segmentation of the right ventricle we first expanded the capability of the technique to segment non-circular shapes. We apply this new polar dynamic programming in a framework that uses user-selected landmarks to segment the right ventricle in the four chamber view. We also explore the use of four chamber right ventricular segmentation to segment short-axis views of the right ventricle.

A avaliação do ventrículo esquerdo (VE) é uma das principais contribuições da ecocardiografia no estudo da função cardíaca e inclui a mensuração dos diâmetros da cavidade e espessura das paredes em diástole e sístole. O estudo por meio do modo M tem sido usado como padrão para a realização da mensuração e para o cálculo de índices sistólicos, mas o modo bidimensional também é utilizado para este fim. As medidas podem ser adquiridas a partir de dois planos de imagem: transversal e longitudinal. A definição de intervalos de confiança para valores normais de VE permite a identificação de remodelamento ventricular, concêntrico ou excêntrico, decorrente de doenças cardiovasculares ou sistêmicas. Assim sendo, o objetivo deste estudo foi comparar as medidas ecocardiográficas desta câmara obtidas pelos seguintes métodos: modo M em corte transversal, modo M em corte longitudinal, modo bidimensional em corte transversal e modo bidimensional em corte longitudinal. Adicionalmente, estudou-se o comportamento do efeito do peso e do sexo nos métodos mencionados. Foram selecionados 40 cães adultos da raça Pastor Alemão sem alterações cardiovasculares. A realização do ecocardiograma de cada animal inclui os quatro métodos descritos acima, de acordo com o recomendado pela literatura. Foram pesquisados os efeitos do corte e do método, bem como a influência do peso e do sexo, sobre cada medida estudada, linear ou derivada. O peso apresentou correlação com todas as medidas lineares de VE em pelo menos um dos métodos, mas não com fração de encurtamento (FE) e fração de ejeção (FEj). Utilizando-se a análise univariada, verificou-se que machos apresentaram todas as medidas estudadas significativamente maiores que fêmeas em pelo menos um dos métodos, exceto FE e FEj, cujos valores não foram diferentes entre os sexos. Observou-se efeito isolado do corte apenas sobre diâmetro diastólico final do ventrículo esquerdo (DdFVE), com medidas maiores obtidas no corte transversal, e mudança de comportamento do sexo nos cortes com influência significativa do peso sobre septo interventricular em diástole (SIVd). Houve efeito isolado do modo sobre os índices de função sistólica FE e FEj, com valores maiores fornecidos pelo modo M. O peso teve efeito isolado positivo sobre parede livre de ventrículo esquerdo em diástole (PLVEd), exceto no modo M em corte transversal e (diâmetro sistólico final de ventrículo esquerdo (DsFVE). O sexo, retirada a influência do peso, teve efeito isolado apenas sobre DdFVE, com machos apresentando valores significativamente maiores que fêmeas em ambos os cortes no modo bidimensional. Os resultados Os resultados mostram que há risco de erro de interpretação quando valores normais de referência, gerados a partir de determinado método, são utilizados para a avaliação de um paciente examinado por técnica de mensuração diversa, especialmente quando se obtém resultados nos limites superior ou inferior de normalidade. / Left ventricle (LV) evaluation is one of the most important contributions of echocardiography in the assessment of cardiac function. It includes measurements of internal diameter and wall thickness at end-diastole and end-sistole of this chamber. M Mode echocardiography has been widely used for measuring linear dimensions and quantifying systolic function, but bidimensional mode is also used with the same purpose. The LV measurement can be derived from transverse or longitudinal images of the heart. The establishment of normal confidence intervals of LV dimensions allows identification of concentric or excentric ventricular remodeling process secondary to cardiovascular and systemic diseases. The aim of this study was to compare LV measurements obtained from four methods: M mode in short-axis, M mode in long-axis, bidimensional mode in short-axis and bidimensional mode in long-axis view of the heart. In addition the effect of weight and gender over measures was studied in the methods mentioned above. Forty adult German Shepherds without cardiovascular diseases were selected. The echocardiogram of each animal included the four described methods, according previous referenced recommendations. The effects of axis and mode as well as weight and gender were studied for each linear or derived LV measure. Weight correlated with all linear LV measures at least in one method, but not with ejection fraction (EF) and shortening fraction (SF). All LV measures of males were greater than those of females at least in one method, except for EF and SF, which did not differ between sexes. Isolated effect of the axis was observed only for LV end diastolic diameter (LVEDD), with greater values obtained from short-axis views. The combined effect of axis, gender and weight was identified in interventricular septal end diastolic thickness. There was isolated effect of mode over EF and SF, with greater measures derived from bidimensional mode methods. Weight had isolated significant positive effect over LV enddiastole posterior wall thickness in all methods, except from M mode performed in short axis, and LV end-sistolic diameter. Gender had isolated effect only over LVEDD, males showing greater values than females in bidimensional mode in short and long axis. Professionals should be aware of the possibility of erroneous interpretation when using data obtained by a different method of that used in the patient exam as reference, mainly for the values situated in inferior and superior limits of confidence intervals.

A avaliação do ventrículo esquerdo (VE) é uma das principais contribuições da ecocardiografia no estudo da função cardíaca e inclui a mensuração dos diâmetros da cavidade e espessura das paredes em diástole e sístole. O estudo por meio do modo M tem sido usado como padrão para a realização da mensuração e para o cálculo de índices sistólicos, mas o modo bidimensional também é utilizado para este fim. As medidas podem ser adquiridas a partir de dois planos de imagem: transversal e longitudinal. A definição de intervalos de confiança para valores normais de VE permite a identificação de remodelamento ventricular, concêntrico ou excêntrico, decorrente de doenças cardiovasculares ou sistêmicas. Assim sendo, o objetivo deste estudo foi comparar as medidas ecocardiográficas desta câmara obtidas pelos seguintes métodos: modo M em corte transversal, modo M em corte longitudinal, modo bidimensional em corte transversal e modo bidimensional em corte longitudinal. Adicionalmente, estudou-se o comportamento do efeito do peso e do sexo nos métodos mencionados. Foram selecionados 40 cães adultos da raça Pastor Alemão sem alterações cardiovasculares. A realização do ecocardiograma de cada animal inclui os quatro métodos descritos acima, de acordo com o recomendado pela literatura. Foram pesquisados os efeitos do corte e do método, bem como a influência do peso e do sexo, sobre cada medida estudada, linear ou derivada. O peso apresentou correlação com todas as medidas lineares de VE em pelo menos um dos métodos, mas não com fração de encurtamento (FE) e fração de ejeção (FEj). Utilizando-se a análise univariada, verificou-se que machos apresentaram todas as medidas estudadas significativamente maiores que fêmeas em pelo menos um dos métodos, exceto FE e FEj, cujos valores não foram diferentes entre os sexos. Observou-se efeito isolado do corte apenas sobre diâmetro diastólico final do ventrículo esquerdo (DdFVE), com medidas maiores obtidas no corte transversal, e mudança de comportamento do sexo nos cortes com influência significativa do peso sobre septo interventricular em diástole (SIVd). Houve efeito isolado do modo sobre os índices de função sistólica FE e FEj, com valores maiores fornecidos pelo modo M. O peso teve efeito isolado positivo sobre parede livre de ventrículo esquerdo em diástole (PLVEd), exceto no modo M em corte transversal e (diâmetro sistólico final de ventrículo esquerdo (DsFVE). O sexo, retirada a influência do peso, teve efeito isolado apenas sobre DdFVE, com machos apresentando valores significativamente maiores que fêmeas em ambos os cortes no modo bidimensional. Os resultados Os resultados mostram que há risco de erro de interpretação quando valores normais de referência, gerados a partir de determinado método, são utilizados para a avaliação de um paciente examinado por técnica de mensuração diversa, especialmente quando se obtém resultados nos limites superior ou inferior de normalidade. / Left ventricle (LV) evaluation is one of the most important contributions of echocardiography in the assessment of cardiac function. It includes measurements of internal diameter and wall thickness at end-diastole and end-sistole of this chamber. M Mode echocardiography has been widely used for measuring linear dimensions and quantifying systolic function, but bidimensional mode is also used with the same purpose. The LV measurement can be derived from transverse or longitudinal images of the heart. The establishment of normal confidence intervals of LV dimensions allows identification of concentric or excentric ventricular remodeling process secondary to cardiovascular and systemic diseases. The aim of this study was to compare LV measurements obtained from four methods: M mode in short-axis, M mode in long-axis, bidimensional mode in short-axis and bidimensional mode in long-axis view of the heart. In addition the effect of weight and gender over measures was studied in the methods mentioned above. Forty adult German Shepherds without cardiovascular diseases were selected. The echocardiogram of each animal included the four described methods, according previous referenced recommendations. The effects of axis and mode as well as weight and gender were studied for each linear or derived LV measure. Weight correlated with all linear LV measures at least in one method, but not with ejection fraction (EF) and shortening fraction (SF). All LV measures of males were greater than those of females at least in one method, except for EF and SF, which did not differ between sexes. Isolated effect of the axis was observed only for LV end diastolic diameter (LVEDD), with greater values obtained from short-axis views. The combined effect of axis, gender and weight was identified in interventricular septal end diastolic thickness. There was isolated effect of mode over EF and SF, with greater measures derived from bidimensional mode methods. Weight had isolated significant positive effect over LV enddiastole posterior wall thickness in all methods, except from M mode performed in short axis, and LV end-sistolic diameter. Gender had isolated effect only over LVEDD, males showing greater values than females in bidimensional mode in short and long axis. Professionals should be aware of the possibility of erroneous interpretation when using data obtained by a different method of that used in the patient exam as reference, mainly for the values situated in inferior and superior limits of confidence intervals.

Single photon emission tomography (SPECT) data from myocardial perfusion imaging (MPI) are normally displayed as a set of three slices orthogonal to the left ventricular (LV) long axis for both ECG-gated (GSPECT) and non-gated SPECT studies. The total number of slices presented for assessment depends on the size of the heart, but is typically in excess of 30.  A requirement for data presentation is that images should be orientated about the LV axis; therefore, a set of radial slice would fulfill this need. Radial slices are parallel to the LV long axis and arranged diametrically. They could provide a suitable alternative to standard orthogonal slices, with the advantage of requiring far fewer slices to adequately represent the data. In this study a semi-automatic method was developed for displaying MPI SPECT data as a set of radial slices orientated about the LV axis, with the aim of reducing the number of slices viewed, without loss of information and independent on the size of the heart. Input volume data consisted of standard short axis slices orientated perpendicular to the LV axis chosen at the time of reconstruction.  The true LV axis was determined by first determining the boundary on a central long axis slice, the axis being in the direction of the y-axis in the matrix. The skeleton of the myocardium were found and the true LV axis determined for that slice. The angle of this axis with respect to the y-axis was calculated. The process was repeated for an orthogonal long axis slice. The input volume was then rotated by the angles calculated. Radial slices generated for presentation were integrated over a sector equivalent to the imaging resolution (1.2 cm); assuming the diameter of the heart is about 8cm then non-gated data could be represented by 20 radial slices integrated over an 18 degree section. Gated information could be represented with four slices spaced at 45 intervals, integrated over a 30 degree sector.