Objective- The purpose of this study was to investigate the feasibility of performing echocardiography in apparently healthy pigeons, and measurement of the quantitative cardiac indices using B-mode and Doppler techniques. Design- Experimental study Animals- Ten apparently healthy pigeons Procedures- Echocardi...

BACKGROUND Portal hypertension is a common consequence of hepatic cirrhosis, which causes esophageal varices. Bleeding from varices has a high mortality rate. The present gold standard for diagnosing varices is endoscopy. Considering endoscopy side effects and patients' low acceptance, there have been always efforts for finding alternative diagnostic methods including Doppler ultrasonography (U...

Background: Transmitral Doppler flow indices are used to evaluate diastolic function. Recently, velocities measured by Doppler tissue imaging have been used as an index of left ventricular relaxation. Objective: To determine whether Doppler tissue velocities are influenced by alterations in preload. Methods: Left ventricular preload was altered in 17 patients (all men, mean (SD) age, 49 (8) yea...

BACKGROUND Transmitral Doppler flow indices are used to evaluate diastolic function. Recently, velocities measured by Doppler tissue imaging have been used as an index of left ventricular relaxation. OBJECTIVE To determine whether Doppler tissue velocities are influenced by alterations in preload. METHODS Left ventricular preload was altered in 17 patients (all men, mean (SD) age, 49 (8) ye...

The advent of modern Doppler two-dimensional ultrasound technology has overcome the need of invasive measurements of several important cardiac parameters. It allows estimation of preload, contractility, and afterload. Positive end-expiratory pressure (PEEP) is associated with a reduction in cardiac output. The responsible mechanisms are controversial. To evaluate the cardiovascular responses to...

Most of the important clinical indices of blood flow are estimated from the spectrograms of Doppler ultrasound (US) signals. Any noise may degrade the readability of the spectrogram and the precision of the clinical indices, so the spectral enhancement plays an important role in Doppler US signal processing. A new Doppler US spectral enhancement method is proposed in this paper and implemented ...