Positive correlation between echocardiographic tricuspid E peak velocity and central venous pressure in dogs: A preliminary study.

In the absence of vascular obstruction, central venous pressure (CVP) is a hydrostatic pressure in the cranial and caudal vena cava, providing valuable information about cardiac function and intravascular volume status. It is also a component in evaluating volume resuscitation in patients with septic shock and monitoring patients with right heart disease, pericardial disease, or volume depletion. Central venous pressure is calculated in dogs by invasive central venous catheterization, which is considered high-risk and impractical in critically ill patients. This study aimed to investigate the feasibility of using echocardiographic tricuspid E/E' as a noninvasive method to estimate CVP in anesthetized healthy dogs under controlled hypovolemic conditions. Ten male mixed-breed dogs were included in the study after a thorough health assessment. For hypovolemia induction, blood withdrawal was performed, and echocardiographic factors of the tricuspid valve, including peak E and E' velocities, were measured during CVP reduction. Repeated measures analysis of variance and Bonferroni post hoc tests were employed to compare the average difference between measured echocardiographic indices and CVP values derived from catheterization and intermittent measurement methods. Spearman's ρ correlation coefficient was used to evaluate the correlation between echocardiographic indices and CVP. E peak velocity had a significant negative correlation with venous blood pressure phases (r = -0.44, P = .001), indicating a decrease in peak E velocity with progressive CVP reduction. However, tricuspid valve E' peak velocity and E/E' did not correlate with CVP, suggesting that these parameters are not reliable for CVP estimation in dogs.

Anatomical study of pericardioperitoneal canal in immature beluga (Huso huso) with ultrasonography.

BACKGROUND: One of the special anatomical structures in sturgeons is the pericardioperitoneal canal (PPC), which has not been studied much. Considering that the presence and absence of this channel and its morphometry have not been investigated in this type of fish, this study was conducted. OBJECTIVE: The purpose of present study was to obtain a complete understanding about anatomical features and ultrasonography of PPC in the heart of immature beluga species in order to provide standard approaches for performing sonography and echocardiography on this sturgeon species. METHODS: Ten immature belugas (Huso huso) were used to perform ultrasonography with Sonosite MicroMaxx ultrasonography machine of ventral approach between two pectoral fins. After performing the steps of ultrasonographic study, gross anatomical studies were also performed, and the morphometric measurement of the canal was also performed. RESULTS: A small PPC was observed, which communicated between the pericardial cavity, and the peritoneal (coelomic) cavity. The cranial part of this channel, which was located immediately after the transverse septum, was on the midline of the body and was seen in midsagittal ultrasonograms. On average, the length of this canal was 3.23 ± 0.05 cm, and its diameter (cranial part) was 0.24 ± 0.04 cm. CONCLUSIONS: In the present study on immature beluga, it was observed that the canal is located behind the sinus venosus and is caudoventral to it, though behind the transverse septum. It has been mentioned that this PPC establishes a connection between the pericardial cavity and the peritoneal cavity, so this connection is between the peritoneal cavity and the space between the two layers of the pericardium and has no connection with the pericardial sac (the space where the heart is located). In this study, the anatomical structure and morphometry of the PPC in immature beluga were investigated, and some approaches were presented to observe the canal in ultrasonography.

Right parasternal echocardiographic reference values in the healthy male Iranian Shall sheep.

BACKGROUND: Among the large animals, the heart of sheep is functionally and structurally very similar to the human heart. In research, sheep are used as an animal model to study the process of cardiac disease pathogenesis and treatment. Therefore, determining the normal values of the heart structures of sheep with echocardiography is of particular emphasis. The purpose of the present research is to define the normal echocardiography values of heart in Iranian Shall breed sheep. MATERIALS AND METHODS: In 20 healthy Iranian Shall male sheep weighing 30-35 kg and aged 4-6 months, standing echocardiography was done from the right parasternal approach concentrated on the 3rd to 5th intercostal spaces by 2.5-5 MHz phased array transducer in the longitudinal and transverse views by B-mode, M-mode and Doppler systems. In M-mode echocardiographic, the parameters of interventricular septal, left ventricular internal diameter, left ventricular free wall, right ventricular free wall and right ventricular internal diameter in diastole and systole as well as end point septal separation, ejection fraction (EF) slope, aortic root diameter, left atrial appendage, left atrial diameter/aortic valve diameter, left ventricular ejection time, fractional shortening, end-diastolic volume, end-systolic volume, EF, stroke volume and cardiac output and in pulsed-wave spectral Doppler echocardiographic, the parameters of mitral valve maximum velocity (Vmax), mitral valve mean velocity (Vmean), mitral valve maximum pressure gradient (PGmax), mitral valve mean pressure gradient (PGmean), mitral valve velocity time integral (VTI), mitral valve E-wave (MV-E), MV-E pressure gradient, mitral valve A-wave (MV-A), MV-A pressure gradient, aortic Vmax, aortic valve Vmean, aortic valve PGmax, aortic valve PGmean, aortic valve VTI, left ventricular outflow tract (LVOT)-Vmax, LVOT-Vmean were measured. RESULTS: All the sheep in this study were healthy and had no signs of heart disease. In this study, the parameters of M-mode and spectral Doppler echocardiographic were assessed and recognized in Iranian Shall sheep. The results demonstrated the parameters of echocardiographic could be dependably determined in Shall sheep which, established normal reference values for these parameters and left ventricular function indices in healthy Shall sheep. These results can be beneficial in appropriate imagination, recognition and measuring cardiac structures. CONCLUSION: This study can be exerted as a reference for the assessment and diagnosis of heart diseases in sheep medicine and human cardiovascular research in sheep experimental models.