RESUMEN
BACKGROUND: Reports on the incidence and causes of sudden cardiac death among young athletes have relied largely on estimated rates of participation and varied methods of reporting. We sought to investigate the incidence and causes of sudden cardiac death among adolescent soccer players in the United Kingdom. METHODS: From 1996 through 2016, we screened 11,168 adolescent athletes with a mean (±SD) age of 16.4±1.2 years (95% of whom were male) in the English Football Association (FA) cardiac screening program, which consisted of a health questionnaire, physical examination, electrocardiography, and echocardiography. The FA registry was interrogated to identify sudden cardiac deaths, which were confirmed with autopsy reports. RESULTS: During screening, 42 athletes (0.38%) were found to have cardiac disorders that are associated with sudden cardiac death. A further 225 athletes (2%) with congenital or valvular abnormalities were identified. After screening, there were 23 deaths from any cause, of which 8 (35%) were sudden deaths attributed to cardiac disease. Cardiomyopathy accounted for 7 of 8 sudden cardiac deaths (88%). Six athletes (75%) with sudden cardiac death had had normal cardiac screening results. The mean time between screening and sudden cardiac death was 6.8 years. On the basis of a total of 118,351 person-years, the incidence of sudden cardiac death among previously screened adolescent soccer players was 1 per 14,794 person-years (6.8 per 100,000 athletes). CONCLUSIONS: Diseases that are associated with sudden cardiac death were identified in 0.38% of adolescent soccer players in a cohort that underwent cardiovascular screening. The incidence of sudden cardiac death was 1 per 14,794 person-years, or 6.8 per 100,000 athletes; most of these deaths were due to cardiomyopathies that had not been detected on screening. (Funded by the English Football Association and others.).
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Atletas , Muerte Súbita Cardíaca/epidemiología , Cardiopatías/diagnóstico , Tamizaje Masivo , Fútbol , Adolescente , Cardiomiopatías/complicaciones , Cardiomiopatías/diagnóstico , Causas de Muerte , Muerte Súbita Cardíaca/etiología , Errores Diagnósticos , Ecocardiografía , Electrocardiografía , Femenino , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Cardiopatías/complicaciones , Cardiopatías/epidemiología , Cardiopatías/mortalidad , Humanos , Incidencia , Masculino , Examen Físico , Reino Unido/epidemiologíaRESUMEN
BACKGROUND: Guidelines advocate using B-type natriuretic peptides in the diagnostic work-up of suspected heart failure (HF). Their main role is to limit echocardiography rates by ruling out HF/LV dysfunction where peptide level is low. Recommended rule-out cut points vary between guidelines. The utility of B-type natriuretic peptides in the very old (85+) requires further investigation, with optimal cut points yet to be established. We examined NT-proBNP's utility, alone and in combination with history of myocardial infarction (MI), as a rule-out test for LV dysfunction in very old people with limiting dyspnoea. DESIGN: Cross-sectional analysis. SETTING: Population-based sample; North-East England. PARTICIPANTS: 155 people (aged 87-89) with limiting dyspnoea. MEASURES: Dyspnoea assessed by questionnaire. Domiciliary echocardiography performed; LV systolic/diastolic function graded. NT-proBNP measured (Roche Diagnostics). Receiver operating characteristic analyses examined NT-proBNP's diagnostic accuracy for LV dysfunction. RESULTS: AUC for LVEF less than or equal to 50% was poor (0.58, 95% CI 0.49-0.65), but good for LVEF less than or equal to 40% (0.80, 95% CI 0.73-0.86). At ESC cut point (125 ng/l), few cases of systolic dysfunction were missed (NPV 94-100%, depending on severity), but echocardiography (88%) and false positive rates (56-81 per 100 screened) were high. At NICE cut point (400 ng/l), echocardiography (51%) and false positive rates (33-45) were lower; exclusionary performance was good for LVEF less than or equal to 40% (1 case missed per 100 screened, 15% of cases; NPV 97%), but poor for LVEF less than or equal to 50% (16 cases missed per 100 screened, 45% of cases; NPV 68%). Incorporating isolated moderate/severe diastolic dysfunction into target condition increased the proportion of cases missed (lower NPV), whilst improving case detection. Incorporating MI history as an additional referral prompt slightly reduced the number of cases missed at expense of higher echocardiography and false positive rates. CONCLUSIONS: High echocardiography rates and poor exclusionary performance for mild degrees of systolic dysfunction and for diastolic dysfunction limit NT-proBNP's utility as a rule-out test for LV dysfunction in very old people with limiting dyspnoea. Incorporating MI history as an additional echocardiography prompt yields no overall benefit compared to using NT-proBNP level alone.
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Disnea/etiología , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Disfunción Ventricular Izquierda/sangre , Disfunción Ventricular Izquierda/diagnóstico , Función Ventricular Izquierda , Factores de Edad , Anciano de 80 o más Años , Área Bajo la Curva , Biomarcadores/sangre , Estudios Transversales , Disnea/diagnóstico , Ecocardiografía , Inglaterra , Femenino , Humanos , Estudios Longitudinales , Masculino , Infarto del Miocardio/complicaciones , Valor Predictivo de las Pruebas , Curva ROC , Factores de Riesgo , Índice de Severidad de la Enfermedad , Volumen Sistólico , Encuestas y Cuestionarios , Disfunción Ventricular Izquierda/complicaciones , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
BACKGROUND AND AIM: The efficacy of pre-COVID-19 and post-COVID-19 infection 12-lead ECGs for identifying athletes with myopericarditis has never been reported. We aimed to assess the prevalence and significance of de-novo ECG changes following COVID-19 infection. METHODS: In this multicentre observational study, between March 2020 and May 2022, we evaluated consecutive athletes with COVID-19 infection. Athletes exhibiting de-novo ECG changes underwent cardiovascular magnetic resonance (CMR) scans. One club mandated CMR scans for all players (n=30) following COVID-19 infection, despite the absence of cardiac symptoms or de-novo ECG changes. RESULTS: 511 soccer players (median age 21 years, IQR 18-26 years) were included. 17 (3%) athletes demonstrated de-novo ECG changes, which included reduction in T-wave amplitude in the inferior and lateral leads (n=5), inferior leads (n=4) and lateral leads (n=4); inferior T-wave inversion (n=7); and ST-segment depression (n=2). 15 (88%) athletes with de-novo ECG changes revealed evidence of inflammatory cardiac sequelae. All 30 athletes who underwent a mandatory CMR scan had normal findings. Athletes revealing de-novo ECG changes had a higher prevalence of cardiac symptoms (71% vs 12%, p<0.0001) and longer median symptom duration (5 days, IQR 3-10) compared with athletes without de-novo ECG changes (2 days, IQR 1-3, p<0.001). Among athletes without cardiac symptoms, the additional yield of de-novo ECG changes to detect cardiac inflammation was 20%. CONCLUSIONS: 3% of athletes demonstrated de-novo ECG changes post COVID-19 infection, of which 88% were diagnosed with cardiac inflammation. Most affected athletes exhibited cardiac symptoms; however, de-novo ECG changes contributed to a diagnosis of cardiac inflammation in 20% of athletes without cardiac symptoms.
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COVID-19 , Fútbol , Humanos , Adulto Joven , Adulto , Prevalencia , COVID-19/complicaciones , COVID-19/epidemiología , Electrocardiografía , Arritmias Cardíacas/diagnóstico , Atletas , Inflamación , Prueba de COVID-19RESUMEN
OBJECTIVES: The purpose of this study was to investigate whether cardiac output (CO) could be accurately computed from live three-dimensional (3-D) Doppler echocardiographic data in an acute open-chested animal preparation. BACKGROUND: The accurate measurement of CO is important in both patient management and research. Current methods use invasive pulmonary artery catheters or two-dimensional (2-D) echocardiography or esophageal aortic Doppler measures, with the inherent risks and inaccuracies of these techniques. METHODS: Seventeen juvenile, open-chested pigs were studied before undergoing a separate cardiopulmonary bypass procedure. Live 3-D Doppler echocardiography images of the left ventricular outflow tract and aortic valve were obtained by epicardial scanning, using a Philips Medical Systems (Andover, Massachusetts) Sonos 7500 Live 3-D Echo system with a 2.5-MHz probe. Simultaneous CO measurements were obtained from an ultrasonic flow probe placed around the aortic root. Subsequent offline processing using custom software computed the CO from the digital 3-D Doppler DICOM data, and this was compared to the gold standard of the aortic flow probe measurements. RESULTS: One hundred forty-three individual CO measurements were taken from 16 pigs, one being excluded because of severe aortic regurgitation. There was good correlation between the 3-D Doppler and flow probe methods of CO measurement (y = 1.1x - 9.82, R(2) = 0.93). CONCLUSIONS: In this acute animal preparation, live 3-D Doppler echocardiographic data allowed for accurate assessment of CO as compared to the ultrasonic flow probe measurement.
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Gasto Cardíaco , Ecocardiografía Doppler en Color , Ecocardiografía Tridimensional , Animales , Velocidad del Flujo Sanguíneo , Puente Cardiopulmonar , Estudios de Factibilidad , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Animales , Reproducibilidad de los Resultados , PorcinosRESUMEN
The determination of stroke volume (SV) is a potentially important application of real-time 3-dimensional echocardiography (RT3DE). SV measurements by thermodilution were compared with values obtained using transthoracic RT3DE in a sequential cohort of patients who underwent assessment for potential cardiac transplantation. There was a strong correlation between echocardiographically derived SV and catheterization data (r = 0.95, n = 14). On average, RT3DE appeared to underestimate SV by 7.5 ml (SD = 5.8) or 17% (SD = 12%). A role for RT3DE in the measurement of SV in severe heart failure is suggested.
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Cardiomiopatía Dilatada/diagnóstico por imagen , Ecocardiografía Tridimensional/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Volumen Sistólico , TermodiluciónRESUMEN
Accurately quantifying transmitral flow volume is clinically important not only as a measure of cardiac output, but also as a value from which to subtract aortic flow, for determining the severity of mitral regurgitation. However, controversy exists over the accuracy of pulsed Doppler for mitral flow quantification because of the complexity of mitral flow geometry and dynamic changes in flow profile and flow area. To explore the feasibility of directly quantifying transmitral flow volume with a newly developed dynamic 3-dimensional digital color Doppler technique, this in vivo experimental study was conducted to validate the method. Eight open chest sheep were imaged with a multiplane transesophageal (TEE) probe placed on the heart for digital 3-dimensional gated acquisition of mitral inflow over a 180-degree acquisition. The digital velocity data were contour detected for flow area after computing the velocity vectors and flow profile perpendicular to a spherical 3-dimensional surface across the mitral annulus. Flow areas and actual velocities were then integrated in time and space and the resulting flow volumes were compared with those obtained by a reference electromagnetic flowmeter on the aorta for 26 steady hemodynamic states. The flow volumes correlated closely to the electromagnetic references (y = 0.87x + 2.49, r = 0.92, SEE = 1.9 Ml per beat). Our study shows that transmitral flow volume can be accurately determined in vivo by this dynamic 3-dimensional digital color Doppler flow quantification method.
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Velocidad del Flujo Sanguíneo/fisiología , Ecocardiografía Doppler en Color , Ecocardiografía Tridimensional , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/fisiología , Animales , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiología , Ventrículos Cardíacos/diagnóstico por imagen , Modelos Animales , Modelos Cardiovasculares , Variaciones Dependientes del Observador , Ovinos , Volumen Sistólico/fisiología , Función VentricularRESUMEN
OBJECTIVE: Heart failure (HF) prevalence rises sharply among those aged 85 years and over. Previous population based echocardiographic studies of left ventricular (LV) dysfunction, the substrate for HF, have included only small numbers in this age group. We used domiciliary echocardiography to estimate the prevalence of LV systolic and diastolic dysfunction in 87-89 year olds and the proportion remaining undiagnosed. DESIGN: Cross sectional analysis of data from Newcastle 85+ Study. SETTING: Primary care, North-East England. PARTICIPANTS: 376 men and women aged 87-89 years. MEASURES: Domiciliary echocardiography was performed and LV systolic and diastolic function was graded. The presence of limiting dyspnoea was assessed by questionnaire. Previous diagnoses of HF were abstracted from general practice (GP) records. RESULTS: 32% of participants (119/376) had LV systolic dysfunction (ejection fraction (EF) ≤50%) and a further 20% (75/376) had moderate or severe LV diastolic dysfunction with preserved EF. Both echocardiographic assessment of LV function and dyspnoea status were available in 74% (278/376) of participants. Among these participants, limiting dyspnoea was present in approximately two thirds of those with significant (systolic or isolated moderate/severe diastolic) LV dysfunction. 84% (73/87) of participants with significant LV dysfunction and limiting dyspnoea did not have a pre-existing HF diagnosis in their GP records. Overall, 26% (73/278) of participants with both echocardiographic and dyspnoea data had undiagnosed, symptomatic, significant LV dysfunction. CONCLUSION: Significant systolic and diastolic LV dysfunction is much commoner in community dwelling 87-89 year olds than previous studies have suggested. The majority are both symptomatic and undiagnosed.
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Insuficiencia Cardíaca/epidemiología , Disfunción Ventricular Izquierda/epidemiología , Factores de Edad , Anciano de 80 o más Años , Estudios Transversales , Diástole , Disnea/epidemiología , Ecocardiografía Doppler , Inglaterra/epidemiología , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Prevalencia , Volumen Sistólico , Encuestas y Cuestionarios , Sístole , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular IzquierdaAsunto(s)
Aneurisma de la Aorta/diagnóstico por imagen , Rotura de la Aorta/diagnóstico por imagen , Seno Aórtico/lesiones , Adulto , Aneurisma de la Aorta/cirugía , Rotura de la Aorta/cirugía , Ecocardiografía Transesofágica/métodos , Humanos , Masculino , Seno Aórtico/diagnóstico por imagen , Seno Aórtico/cirugíaRESUMEN
AIMS: Heart failure is a condition increasingly prevalent at older ages; however, mechanisms by which the ageing process affects cardiac function are largely unknown. Telomere length is a biomarker of ageing that has been suggested to be associated with a variety of diseases of late onset, but its relationship with cardiac function has not previously been studied. We measured telomere length in peripheral blood mononuclear cells and carried out echocardiography in a group of 85-year old subjects recruited from the community as part of the Newcastle 85+ Study. METHODS AND RESULTS: Eighty-nine subjects were recruited through local family practitioners. They were visited in their homes for clinical assessment and echocardiography, which was performed using a handheld device. Telomere length was measured by a real-time PCR method. High sensitivity C-reactive protein was measured using ELISA. Echocardiographic M-mode ejection fraction (EF) was strongly associated with telomere length (P=0.006) in subjects without evidence of previous MI. Sex and telomere length were significant predictors of EF while current smoking, blood pressure, plasma high sensitivity C-reactive protein, and use of cardiovascular medications were not. One standard deviation longer telomeres were associated with a 5% higher EF. Telomere length accounted for 12% of the observed variability in EF. CONCLUSION: These data show influences of the ageing process on myocardial function in the oldest old, apparently independent of other specific disease processes. This may be of importance in the aetiology of heart failure in this age group.
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Insuficiencia Cardíaca/patología , Telómero/patología , Disfunción Ventricular Izquierda/patología , Anciano de 80 o más Años , Biomarcadores , Electrocardiografía , Femenino , Humanos , Masculino , Volumen Sistólico/fisiologíaRESUMEN
INTRODUCTION: The aim of the present study was to evaluate a possible association between QT dispersion (QTd) and the amount of viable and scarred myocardial tissue after revascularization in patients with coronary artery disease and impaired left ventricular (LV) function. METHODS: Twenty-two patients with ischemic LV dysfunction underwent dobutamine stress echocardiography (DSE) before and 6 months after surgical revascularization. Mean corrected QT-interval value and QTd were calculated at baseline and follow-up. Segments consisting of transmural scar were determined as the segments that remained akinetic in all stages of DSE despite reperfusion. Patients were divided into 2 groups according to the number of definitive segments consisting of transmural scar (minor scar group, < or =2 scarred segments; major scar group, >2 scarred segments). RESULTS: QTd was significantly lower in the minor compared with the major scar group at baseline and follow-up (mean [SD], 61 [22] vs 98 [33] milliseconds, P = .008, and 45 [18] vs 68 [21] milliseconds, P = .01, respectively). Segments consisting of transmural scar positively correlated to QTd at baseline (r = 0.53, P = .01) and follow-up (r = 0.62, P = .002). CONCLUSIONS: QTd is positively correlated with the extent of scarred myocardial tissue assessed by DSE. Surgical revascularization results in reduction of QTd in all patients with hibernating myocardium and LV dysfunction.
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Cardiomiopatías/fisiopatología , Frecuencia Cardíaca/fisiología , Corazón/fisiopatología , Aturdimiento Miocárdico/fisiopatología , Disfunción Ventricular Izquierda/fisiopatología , Cardiotónicos , Puente de Arteria Coronaria , Dobutamina , Ecocardiografía de Estrés , Humanos , Miocardio/patología , Estudios ProspectivosRESUMEN
OBJECTIVE: We sought to investigate the accuracy of dobutamine stress echocardiography to predict the degree and timing of recovery in resting function and contractile reserve (CR) after revascularization of the hibernating myocardium. METHODS: In all, 24 patients with ischemic cardiomyopathy (ejection fraction < 40%) underwent dobutamine stress echocardiography 1 week before and 6 weeks, 3 months, and 6 months after coronary artery bypass grafting. RESULTS: Recovery rates at 6 weeks, 3 months, and 6 months postoperation were 21%, 33%, and 45% (P < .01) for resting function and 55%, 65%, and 74% (P < .01) for CR. Positive and negative predictive values for recovery of resting function and CR at 6 months postrevascularization were 66% vs 97% (P < .001) and 78% vs 48% (P < .001), respectively. Positive and negative predictive values were both high for recovery of CR at 6 weeks postrevascularization (89% and 78%). CONCLUSIONS: Dobutamine stress echocardiography can predict early recovery in CR postrevascularization with an excellent accuracy but may underestimate the degree of late recovery in CR.
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Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/cirugía , Puente de Arteria Coronaria , Dobutamina , Aturdimiento Miocárdico/diagnóstico por imagen , Aturdimiento Miocárdico/cirugía , Disfunción Ventricular Izquierda/diagnóstico por imagen , Cardiomiopatías/complicaciones , Ecocardiografía/métodos , Prueba de Esfuerzo/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Aturdimiento Miocárdico/complicaciones , Cuidados Posoperatorios/métodos , Pronóstico , Recuperación de la Función , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento , Vasodilatadores , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/prevención & controlRESUMEN
OBJECTIVES: We and others have reported on the use of digital color Doppler sonography from real-time 3-dimensional (3D) echocardiography and its use in accurately calculating cardiac flow volumes, namely stroke volume (SV) and, hence, cardiac output. However, in some patients, image depth is higher than average, and this may affect the accuracy of volume calculation. We sought to investigate the impact of image depth and the accompanying change in signal strength, spatial resolution, and pulse repetition frequency on the accuracy of SV calculation from 3D color Doppler data in an in vitro model. METHODS: A tube model of the left ventricular outflow tract was constructed from plastic tubing and connected to a pulsatile pump. The volume flowing through the tube was imaged using a 3D echocardiography system. Stroke volumes from the pump were computed from the DICOM data using commercially available software and compared with a reference standard of timed volumes with the use of a graduated measuring cylinder over a range of depth settings and SVs. RESULTS: There was good correlation between the 3D-derived SVs and the reference cylinder measures over all depths from 4 to 16 cm at 1-cm increments with a tube diameter of 17 mm, a pump rate of 60 beats/min, and SVs ranging from 20 to 70 mL. The average r(2) value for the 13 different depths was 0.976. However, the accuracy of the 3D method of volume calculation appeared to fall at depths greater than 13 cm, especially at higher SVs. CONCLUSIONS: Stroke volume calculation from real-time 3D color Doppler data in this in vitro study shows that at depths greater than approximately 13 cm, accuracy decreases, especially at higher SVs. This may be due to decreased resolution and the reduced frame rate at these depths. At shallower depths, volume calculation form the 3D Doppler data appears very accurate.
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Ecocardiografía Doppler en Color/métodos , Ecocardiografía Tridimensional/métodos , Volumen Sistólico , Análisis de Varianza , Diseño de Equipo , Humanos , Modelos Lineales , Fantasmas de Imagen , Flujo PulsátilRESUMEN
BACKGROUND: Invasive monitors and noninvasive 2-dimensional echocardiography are the standard clinical methods for stroke volume (SV) and cardiac output computation. We studied the use of real-time color Doppler 3-dimensional (3D) echocardiography (3DE) for the assessment of SV in human beings. METHODS: In all, 55 pediatric and adult patients with good transthoracic windows and a normal aortic valve were studied. Real-time 3DE color Doppler volumes incorporating the left ventricular outflow tract and aortic valve were taken. SV was calculated from the color Doppler data in the 3DE DICOM dataset. This was compared with 2-dimensional echocardiography SV calculation from the pulsed wave velocity through the aortic valve along with the left ventricular outflow tract diameter. RESULTS: Five patients were excluded because of mismatching of the 3D color Doppler segments in the 3D volume. The 3D Doppler volumes from the remaining 50 patients were analyzed. There was good correlation between the patients' averaged 3DE SV calculations and the 2-dimensional echocardiography pulsed wave SV estimation (y = 0.84x + 7.8, r2 = 0.90). CONCLUSION: Real-time 3D Doppler echocardiography can be used to accurately calculate SV and cardiac output, compared with conventional pulsed Doppler measurement, in pediatric and adult patients from transthoracic imaging.
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Gasto Cardíaco , Ecocardiografía Doppler/métodos , Ecocardiografía Tridimensional/métodos , Interpretación de Imagen Asistida por Computador/métodos , Volumen Sistólico , Disfunción Ventricular Izquierda/diagnóstico por imagen , Adolescente , Adulto , Anciano , Niño , Preescolar , Sistemas de Computación , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Ultrasonic imaging methods of receiving at higher frequencies, which are multiples of the transmitting frequencies (harmonic imaging), are well established as a means of improving myocardial visualization in association with intravenous contrast administration. This exploratory study examined the effect of using receive frequencies that were lower than the transmit frequencies while imaging closed chest dogs with an Ensemble wideband, phase inversion contrast program on a modified Siemens Elegra scanner. METHODS: Intravenous bolus injections of 0.75 mL Definity and 1 mL QW7437 were administered to six anesthetized dogs. Intermittent imaging for contrast visualization was performed using either a broadband array, transmitting at 1.4 MHz and receiving at 2.6-3.2 MHz or a broadband 4-7.5 MHz transducer transmitting at 6.0 MHz and receiving at 4.2-4.5 MHz. Contrast enhancement was measured by videodensitometry, sampling mid-cavity and within the myocardium before and after injection. The changes in videodensity from control to after injection were calculated for each method. RESULTS: There was no significant difference in the change in intracavity videodensity between the two imaging strategies although there was near full intracavity saturation in all cases. However, the change in myocardial density was significantly greater for both contrast agents when using receiving frequencies lower than transmitting frequencies (P = 0.02 and 0.03). The difference in duration of the myocardial blush did not reach statistical significance but it tended to persist for longer with the lower receiving frequencies. CONCLUSION: Delivering sound energy at a slightly higher frequency and receiving at lower than the transmit frequency may be an advantageous method of enhancing myocardial perfusion signals during intravenous contrast echocardiography.