Utilidade do Ultrassom intracardíaco no isolamento de veias pulmonares usando cateter-balão a laser / Utility of intracardiac ultrasound imaging to guide pulmonary vein ablation using laser balloon catheter / Utilidad del ultrasonido intracardíaco en el aislamiento de venas pulmonares usando catéter-balón láser

Fundamento: O isolamento das veias pulmonares (IVP) tem sido usado como endpoint para a ablação da fibrilação atrial (FA) com cateter balão. Objetivo: Determinar a utilidade do ultrassom intracardíaco (USIC) para guiar o IVP, usando cateter balão a laser. Métodos: 59 VP foram ablacionadas em 27 cães. Imagens de Doppler foram usadas para identificar os vazamentos do fluxo sanguíneo entre a VP e o balão. Após cada liberação de energia, o cateter de mapeamento circular foi reposicionado para verificar se o isolamento tinha sido obtido. A posição de vazamento foi então correlacionada com a posição do gap no estudo patológico. A análise de regressão logística multivariada foi realizada. Resultados: Cinquenta e nove VP foram submetidas à ablação. O tempo médio de energia liberada foi de 279±177 seg., o diâmetro médio do balão era de 23±3 mm, e o comprimento médio do balão era 25±4 mm. O isolamento completo foi obtido em 38/59 (64 por cento), e foi significantemente mais comum sem vazamento: [30/38 (79 por cento) versus 8/23 (35 por cento), p<0,001]. Isso foi independente do tempo de aplicação (302±223 seg. vs. 266±148 sec., p=ns), potência (3,5 W/cm, 4,5 W/cm, e 5,5 W/cm), diâmetro do balão (24± 3 mm vs. 22± 3 mm, p= ns) e comprimento (27±4 mm vs. 24±4 mm, p=ns). O valor preditivo positivo para previsão de isolamento completo foi de 65 por cento e o valor preditivo negativo foi 83 por cento. Conclusão: Um vazamento identificável entre a VP e o dispositivo de ablação por cateter-balão observado no USIC é preditor de menor taxa de isolamento de VP mais baixas. O USIC pode ser útil para detectar vazamentos a fim de evitar o uso ineficaz de aplicação energia durante a ablação circunferencial da VP. Isto também pode ser útil quando outras energias são utilizadas.

Background: Pulmonary vein isolation (PVI) with balloon catheter has been used as the endpoint for AF ablation. Objective: To determine the usefulness of intracardiac ultrasound (ICUS) to guide PVI using laser balloon catheter. Methods: 59 PVs were ablated in 27 dogs. Doppler imaging was used to identify blood flow leaks between PV and balloon. After each energy delivery, the circular mapping catheter was repositioned to check if isolation had been achieved. The leak position was then correlated with the gap position at the pathological study. Multivariate logistic regression analysis was undertaken. Results: 59 PV were ablated. Mean burn time was 279±177 sec, mean balloon diameter was 23±3 mm, and mean balloon length was 25±4 mm. Complete isolation was achieved in 38/59 (64 percent) cases, and it was significantly more common when there was no leak: [30/38 (79 percent) versus 8/23 (35 percent), p<0.001]. This occurred regardless of time of laser application (302±223 sec. vs. 266±148 sec., p=ns), laser power (3.5 W/cm, 4.5 W/cm, and 5.5 W/cm), balloon diameter (24± 3 mm vs. 22± 3 mm, p=ns) and length (27±4 mm vs. 24±4mm, p=ns). The positive predictive value for predicting incomplete isolation was 65 percent and the negative predictive value was 83 percent. Conclusion: An identifiable leak between PV and the LBA device seen at the ICUS is predictive of lower PV isolation rates. ICUS may be useful for leak detection to avoid ineffective energy application during circumferential PV ablation. This could also be helpful when other types of energy are used.

Fundamento: Se usó el aislamiento de las venas pulmonares (AVP) como endpoint para la ablación de la fibrilación atrial (FA) con catéter-balón. Objetivo: Determinar la utilidad del ultrasonido intracardíaco (USIC) para guiar el AVP, usando catéter-balón láser. Métodos: Se ablacionaron 59 VP en 27 perros. Se usaron imágenes de Doppler para identificar los derrames del flujo sanguíneo entre la VP y el balón. Tras cada liberación de energía, se reposicionó el catéter de mapeamiento circular para verificar si se obtuvo el aislamiento. Se correlaccionó, entonces, la posición del derrame con la posición del gap en el estudio patológico. Se realizó el análisis de regresión logística multivariada. Resultados: Se sometieron 59 VP a la ablación. El tiempo promedio de energía liberada fue de 279±177 seg., el diámetro promedio del balón era de 23±3 mm, y la largura promedio del balón era 25±4 mm. Se obtuvo el aislamiento completo en 38/59 (64 por ciento), y fue significantemente más común sin derrame: [30/38 (79 por ciento) versus 8/23 (35 por ciento), p<0,001]. Eso fue independiente del tiempo de aplicación (302±223 seg. vs. 266±148 sec., p=ns), potencia (3,5 W/cm, 4,5 W/cm, y 5,5 W/cm), diámetro del balón (24± 3 mm vs. 22± 3 mm, p= ns) y largura (27±4 mm vs. 24±4 mm, p=ns). El valor predictivo positivo para la previsión del aislamiento completo fue del 65 por ciento y el valor predictivo negativo fue del 83 por ciento. Conclusión: Un derrame identificable entre la VP y el dispositivo de ablación por catéter-balón observado en el USIC es predictor de menor tasa del aislamiento de la VP más baja. El USIC puede ser útil para detectar derrames a fin de evitar el uso ineficaz de la aplicación de la energía durante la ablación circunferencial de la VP. Ello también puede ser útil cuando se utilizan otras energías.

Accuracy of ultrasonography with color Doppler in ovarian tumor: a systematic quantitative review.

A quantitative systematic review was performed to estimate the accuracy ultrasonography with color Doppler in the diagnosis of ovarian tumors. Studies that compared color Doppler ultrasonography with paraffin-embedded sections parameters for the diagnosis of ovarian tumors were included. Twelve studies were analyzed, which included 2398 women. The pooled sensitivity was 0.87 (95% confidence interval [CI] 0.84-0.90); and the specificity was 0.92 (95%CI, 0.87-0.90). The diagnostic odds ratio for ovarian cancer and borderline lesions versus benign lesions was 125 (95%CI, 55-283). Summary receiver operating characteristic curves were constructed because of heterogeneity in the diagnostic odds ratio. For malignant ovarian cancer and borderline versus benign lesions the area under the curve was 0.9577. In conclusion, ultrasonography with color Doppler is a useful preoperative test for predicting the diagnosis of pelvic masses.

Utility of intracardiac ultrasound imaging to guide pulmonary vein ablation using laser balloon catheter.

BACKGROUND: Pulmonary vein isolation (PVI) with balloon catheter has been used as the endpoint for AF ablation. OBJECTIVE: To determine the usefulness of intracardiac ultrasound (ICUS) to guide PVI using laser balloon catheter. METHODS: 59 PVs were ablated in 27 dogs. Doppler imaging was used to identify blood flow leaks between PV and balloon. After each energy delivery, the circular mapping catheter was repositioned to check if isolation had been achieved. The leak position was then correlated with the gap position at the pathological study. Multivariate logistic regression analysis was undertaken. RESULTS: 59 PV were ablated. Mean burn time was 279+/-177 sec, mean balloon diameter was 23+/-3 mm, and mean balloon length was 25+/-4 mm. Complete isolation was achieved in 38/59 (64%) cases, and it was significantly more common when there was no leak: [30/38 (79%) versus 8/23 (35%), p<0.001]. This occurred regardless of time of laser application (302+/-223 sec. vs. 266+/-148 sec., p=ns), laser power (3.5 W/cm, 4.5 W/cm, and 5.5 W/cm), balloon diameter (24+/- 3 mm vs. 22+/- 3 mm, p=ns) and length (27+/-4 mm vs. 24+/-4mm, p=ns). The positive predictive value for predicting incomplete isolation was 65% and the negative predictive value was 83%. CONCLUSION: An identifiable leak between PV and the LBA device seen at the ICUS is predictive of lower PV isolation rates. ICUS may be useful for leak detection to avoid ineffective energy application during circumferential PV ablation. This could also be helpful when other types of energy are used.

Screening for placental insufficiency by transvaginal uterine artery Doppler at 22-24 weeks of gestation.

OBJECTIVE: To determine the value of routine transvaginal color Doppler assessment of the uterine arteries at 22-24 weeks of gestation in the prediction of placental insufficiency. METHODS: Women with singleton pregnancies scheduled for routine ultrasound scans at 22-24 weeks were offered Doppler assessment of the uterine arteries by transvaginal ultrasound. The pulsatility index (PI) was obtained for each artery and the mean value was calculated. A mean PI >95th percentile was considered increased. Screening characteristics for predicting placental insufficiency, defined as preeclampsia, fetal growth restriction or intrauterine death, were calculated. RESULTS: Doppler examination of the uterine arteries was carried out in 1,057 singleton pregnancies. The mean uterine artery PI was 1.03 and the 95th percentile was 1.55. In 54 cases (5.1%) the mean PI was >1.55 (screen-positive). In the study population there were 48 cases of preeclampsia (5.1%), 72 fetal growth restrictions (7.5%) and 7 intrauterine deaths (0.7%). The screen-positive group showed an incidence of 47.1% of combined adverse results. The relative risks after a positive screening test were 7.3 (CI 4.2-12.6) for pre-eclampsia, 3.9 (CI 2.3 - 6.6) for fetal growth restriction and 4.5 (CI 3.2-6.4) for overall placental insufficiency. CONCLUSIONS: Uterine artery Doppler at 22-24 weeks identifies women at higher risk for the development of subsequent complications of placental insufficiency. This test could be used in combination with other markers to stratify the level of care offered in the third trimester of pregnancy.

Diagnostic accuracy of color Doppler sonographic study of the ureteric jets in evaluation of hydronephrosis.

OBJECTIVE: Hydronephrosis (HN) and obstruction are closely associated, but upper urinary tract dilatation can occur without significant obstruction. Despite some pitfalls, conventional ultrasonography and diuretic renography (DR) are the main means of evaluation of HN in children. Recent reports have demonstrated color Doppler ultrasonography (CDUS) to reliably identify ureteric jets in the bladder. The aim of this study was to evaluate this method as a diagnostic tool to distinguish obstructive from non-obstructive dilatations of the upper tract. METHODS: We evaluated 51 patients (37 boys and 14 girls), aged 3 months to 14 years (median 4 years), who presented with unilateral grade III and IV hydronephrosis with suspicion of pyeloureteral junction obstruction. All patients underwent DR and evaluation of ureteric jets by transverse CDSG of the bladder within a maximum of 2 weeks. Obstruction was considered in the DR when the hydronephrotic unit showed a differential renal function of less than 40%, or when symptomatic intermittent renal colic was present in older children. The number of ureteric jets was counted over a 5-min period and the frequency calculated for each ureteral orifice. Relative jet frequency (RJF) was defined as frequency of the hydronephrotic side divided by total ureteric jet frequency. Receiver-operating characteristic (ROC) plots were constructed to determine the best cut-off for RJF, in order to identify renal units with obstructive hydronephrosis. RESULTS: Twenty-three (45.1%) hydronephrotic units were considered obstructed. The mean RJF differed between obstructive (0.09+/-0.15) and non-obstructive hydronephrosis (0.42+/-0.11) (p<0.001). ROC analysis revealed that RJF <0.25 was the best threshold, and correctly discriminated obstruction in 91.2% of the children with a sensitivity of 87% (95% CI 78.6-98.2%) and specificity of 96.4% (95% CI 87.8-99%). The positive likelihood ratio was 24.3 and the area under the ROC curve was 0.92 (95% CI 0.86-0.98). CONCLUSIONS: RJF <25% was found to be a good indicator of obstruction in children with unilateral hydronephrosis. CDUS evaluation of ureteric jets is an easy and non-invasive method that can be used as an initial diagnostic tool, and in follow-up cases, to differentiate obstructed from non-obstructed hydronephrosis in the pediatric population.

Reference values for Doppler ultrasound parameters of the thyroid in a healthy iodine-non-deficient population.

The aim of this study was to describe normal Doppler parameter values in the thyroid arteries in an iodine-replete region. 165 individuals were randomly selected in a community located in the south-east of Brazil. We obtained a clinical history on each subject and determined serum thyrotropin, antiperoxidase antibodies, thyrotropin receptor antibody (TRAb) and thyroid volumes through ultrasound. Subjects with thyroid disease and those under 20 years of age were excluded. 84 representative subjects (30 men and 54 women) remained. The systolic peak velocity (SPV), resistive index (RI) and pulsatility index (PI) in the superior and inferior thyroid arteries were measured using a 5-12 MHz linear probe. Except for the RI, the distribution of all Doppler parameters was non-gaussian. The median and mean references for the SPV, RI and PI were 24.80 cm s(-1) and 25.85 cm s(-1), 0.60 and 0.62, and 0.98 and 1.04, respectively, for superior thyroid arteries; these reference values for the inferior thyroid artery were 20.92 cm s(-1) and 21.50 cm s(-1), 0.57 and 0.57, and 0.84 and 0.88, respectively (p<0.001). Women had greater SPV values (p<0.01). We have determined reference thyroid Doppler parameter values in our iodine-non-deficient population and prepared tables by sex and age.

[Prospective evaluation of clinical and Doppler ultrasound characteristics of cancer patients with suspicion of deep venous thrombosis]. / Aspectos clínicos e ultra-sonográficos de pacientes com câncer e suspeita de trombose venosa profunda.

PURPOSE: To evaluate Doppler Ultrasound (DUS) in oncology patients suspected of having Deep Venous Thrombosis (DVT) and correlate findings with their clinical characteristics and outcome. METHODS: A study was made with 96 consecutive oncology patients submitted to DUS suspected to have DVT between May 2001 and April 2002. The same radiologist examined 73 women and 23 men, with a median age of 58 years, using DUS equipment, with high frequency linear and convex probes (logic500--GE and HDI5000--Philips). RESULTS: In 42 (43.8%) patients the DUS was considered normal, in 33 (34.4%) DVT was diagnosed and 21 of them had superficial or previous deep venous thrombosis or non conclusive studies. Considering clinical evaluation (and death by PE as caused by DVT) as the gold standard, DUS sensitivity was of 95.9%. There was a statistically significant correlation between DVT and tumor stage at the time of initial diagnosis and patient's survival rate (p<0.05). There was no correlation between DVT and gender, age, type of malignancy, stage of disease at the time of DVT diagnosis and different treatment regimens. CONCLUSION: It was concluded that in cancer patients DUS has a high sensitivity for diagnosis of DVT and that DVT diagnosis in these patients correlates with a shorter overall survival. Since there are no reliable clinical predictors to identify cancer patients with DVT, DUS should be performed whenever DVT is suspected.

Aspectos clínicos e ultra-sonográficos de pacientes com câncer e suspeita de trombose venosa profunda / Prospective evaluation of clinical and Doppler ultrasound characteristics of cancer patients with suspicion of deep venous thrombosis

OBJETIVO: Avaliar as características clínicas e evolução dos pacientes com câncer e suspeita de TVP submetidos à USD e a sua sensibilidade. MÉTODOS: Estudamos 96 pacientes. A mediana da idade foi de 58 anos, sendo que 73 eram do sexo feminino. A USD foi realizada pelo mesmo radiologista em equipamentos digitais (logiq-500-GE e HDI5000-Phillips), com transdutores lineares de alta freqüência e, quando indicado, convexo de 3,5 mHz, utilizando-se modo B e Doppler. RESULTADOS: Sessenta e sete pacientes (69,8 por cento) evoluíram a óbito, sendo que apenas quatro (4,1 por cento) tiveram exame negativo para TVP e a causa do óbito relacionado a TEP. Quarenta e dois pacientes (43,8 por cento) não apresentavam TVP à USD, enquanto 33 (34,4 por cento) apresentaram-na, sendo que os demais (21,8 por cento) tinham TVP antiga ou trombose superficial. Considerando-se a evolução como padrão ouro e qualquer diagnóstico de TEP desses pacientes causado por TVP, a sensibilidade da USD foi de 95,9 por cento. Encontramos correlação estatisticamente significativa entre a presença de TVP e o estadiamento da neoplasia ao diagnóstico (p<0,05) e com a sobrevida dos pacientes (p<0,05). Não encontramos correlações significativas com as demais variáveis estudadas. CONCLUSÃO: A USD tem alta sensibilidade para diagnóstico de TVP em pacientes com câncer. A presença de TVP nessa população de pacientes se correlaciona com uma menor sobrevida e não há características clínicas que nos permitam isolar um subgrupo de pacientes com maior chance de TVP por USD.

PURPOSE: To evaluate Doppler Ultrasound (DUS) in oncology patients suspected of having Deep Venous Thrombosis (DVT) and correlate findings with their clinical characteristics and outcome. METHODS: A study was made with 96 consecutive oncology patients submitted to DUS suspected to have DVT between May 2001 and April 2002. The same radiologist examined 73 women and 23 men, with a median age of 58 years, using DUS equipment, with high frequency linear and convex probes (logic500 - GE and HDI5000 - Philips). RESULTS: In 42 (43.8 percent) patients the DUS was considered normal, in 33 (34.4 percent) DVT was diagnosed and 21 of them had superficial or previous deep venous thrombosis or non conclusive studies. Considering clinical evaluation (and death by PE as caused by DVT) as the gold standard, DUS sensitivity was of 95.9 percent. There was a statistically significant correlation between DVT and tumor stage at the time of initial diagnosis and patient's survival rate (p<0.05). There was no correlation between DVT and gender, age, type of malignancy, stage of disease at the time of DVT diagnosis and different treatment regimens. CONCLUSION: It was concluded that in cancer patients DUS has a high sensitivity for diagnosis of DVT and that DVT diagnosis in these patients correlates with a shorter overall survival. Since there are no reliable clinical predictors to identify cancer patients with DVT, DUS should be performed whenever DVT is suspected.

Vascular color Doppler ultrasound for assessing renovascular hypertension: accuracy of the direct technique for assessing the renal arteries.

OBJECTIVE: To assess the accuracy of vascular color Doppler ultrasound as compared with digital subtraction arteriography for identifying hemodynamically significant renal artery stenoses. METHODS: One hundred and thirty-seven renal arteries from 69 adult patients suspected of having renovascular arterial hypertension were prospectively studied with ultrasound. The results obtained were compared in a double-blind manner with those obtained on digital subtraction arteriography, and the following parameters were calculated according to previously defined criteria: sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy. RESULTS: The inconclusive results (7 arteries) were excluded. The comparison of the 2 methods in regard to the 130 remaining arteries showed concordant results for 116 (89.2%) arteries and discordant results for 14 (10.8%) arteries. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of vascular color Doppler ultrasound were, respectively, 95.33%, 88.14%, 89.86%, 94.55%, and 91.94%. CONCLUSION: A good correlation between the 2 examinations was observed in the evaluation of the hemodynamically significant renal artery stenoses, making vascular color Doppler ultrasound a noninvasive method useful for selecting patients with suspected renovascular hypertension.

O papel da ultra-sonografia vascular com Doppler colorido na avaliação da hipertensão reno-vascular: acurácia da técnica direta de avaliação das artérias renais / Vascular color Doppler ultrasound for assessing renovascular hypertension: accuracy of the direct technique for assessing the renal arteries

OBJETIVO: Avaliar a acurácia da ultra-sonografia vascular com Doppler colorido em relação à arteriografia digital por subtração de imagens, na identificação das estenoses hemodinamicamente significativas, nas artérias renais. MÉTODOS: Estudados, prospectivamente, pelo exame ultra-sonográfico, 137 artérias renais de 69 pacientes adultos, com suspeita de hipertensão arterial reno-vascular. Os resultados obtidos foram comparados, de maneira duplo-cega, ao estudo arteriográfico digital por subtração de imagens, e calculados a sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia geral do exame para critérios previamente definidos. RESULTADOS: Na comparação entre os métodos, excluindo-se os laudos inconclusivos (7 artérias), das 130 artérias restantes, 116 (89,2 por cento) artérias tiveram laudos concordantes e 14 (10,8 por cento) discordantes. Os valores de sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia geral da ultra-sonografia vascular com Doppler colorido foram respectivamente 95,33 por cento, 88,14 por cento, 89,86 por cento, 94,55 por cento e 91,94 por cento. CONCLUSAO: Existiu boa correlação entre os dois exames na avaliação das estenoses hemodinamicamente significativas das artérias renais, tornando-se a ultra-sonografia vascular com Doppler colorido método não invasivo útil na seleção de pacientes com suspeita de hipertensão reno-vascular.

US Doppler de mama: aportes para la imagen problema / Breast Doppler US with microbuble contrast agent

Efectuamos un análisis de 20 exploraciones ecográficas de alteraciones mamarias que habían sido consideradas dudosas mediante el control clínico y mamográfico. Se utilizó la técnica del Doppler Color, pulsado y potenciado, asociando la incorporación de medio de contraste eco realzador (Levovist). La evaluación se efectuó con y sin software de medios de contraste. En todos los casos se efectuó correlación histopatológica. Ocho lesiones fueron malignas. En estas condiciones podemos decir, que el US Doppler ha demostrado habilidad para poner en evidencia otros signos de atipía, constituyéndose en un aliado de la mamografía y el US convencional

US Doppler de mama: aportes para la imagen problema / Breast Doppler US with microbuble contrast agent

Efectuamos un análisis de 20 exploraciones ecográficas de alteraciones mamarias que habían sido consideradas dudosas mediante el control clínico y mamográfico. Se utilizó la técnica del Doppler Color, pulsado y potenciado, asociando la incorporación de medio de contraste eco realzador (Levovist). La evaluación se efectuó con y sin software de medios de contraste. En todos los casos se efectuó correlación histopatológica. Ocho lesiones fueron malignas. En estas condiciones podemos decir, que el US Doppler ha demostrado habilidad para poner en evidencia otros signos de atipía, constituyéndose en un aliado de la mamografía y el US convencional (AU)

Doppler color y modo de energía como nuevo método diagnóstico en el tumor del cuerpo carotídeo ventajas y desventajas

Se revisaron los hallazgos en Doppler color y modo de energía en 12 pacientes con 14 tumores del cuerpo carotídeo. El diagnóstico se estableció con Doppler color en el que se encontraron masas sólidas en la bifurcación carotídea con flujo intratumoral radial y centrípeto con una curva espectral de baja velocidad, monofásica con perdida de la pulsatilidad y ventana llena. se identificó claramente la relación del tumor con las arterias carótidas lo que permitió su clasificación; 7 de tipo I, 6 de tipo II y 1 de tipo III. La velocidad intratumoral fue significativamente más baja que las velocidades en la porción cervical de las carótidas, hallazgos compatiblescon la neoformación vascular. No existe diferencia significativa en la velocidad de las arterias carótidas del lado del tumor con las contralaterales. Dado que en el 37.5 por ciento de los pacientes programados para cirugía la desición se tomó con base en los hallazgos del Doppler color como único método diagnóstico, se plantea que sea utilizado como primer estudio en pacientes con masa en ecuello a la altura de la bifurcación carotídea, complementandose con Doppler transcraneano o arteriografía en los tipos III

Parametros normales en Doppler Duplex obstétrico: tablas de índices de resistencia (IR) / Obstetric Doppler Duplex sonography

En el Servicio de Radiología del Hospital Francés de Buenos Aires se efectuaron 200 estudios Dopper-Duplex color obstétrico. El objetivo de nuestro trabajo fue la elaboración de tablas con valores normales de índices de resistencia (IR) de arterias uterina, umbilical, cerebral y aorta fetal en pacientes asintomáticas, comprendidas entre las semanas 26 y 38, a fin de poder ser utilizadas como parámetros de referencia en nuestro medio

Parametros normales en Doppler Duplex obstétrico: tablas de índices de resistencia (IR) / Obstetric Doppler Duplex sonography

En el Servicio de Radiología del Hospital Francés de Buenos Aires se efectuaron 200 estudios Dopper-Duplex color obstétrico. El objetivo de nuestro trabajo fue la elaboración de tablas con valores normales de índices de resistencia (IR) de arterias uterina, umbilical, cerebral y aorta fetal en pacientes asintomáticas, comprendidas entre las semanas 26 y 38, a fin de poder ser utilizadas como parámetros de referencia en nuestro medio (AU)