Pulmonary Venous Flow in Normal Dogs Recorded by Transthoracic Echocardiography: Techniques, Anatomic Validations and Flow Characteristics.

Abstract

ABSTRACT. To observe pulmonary venous flow in dogs, the echocardiographic imaging planes and the techniques for examination, and the validations of anatomic location were investigated. Then, the velocity pattern of pulmonary venous flow was recorded in normal conscious dogs. Six imaging planes were available for observing the right or left caudal lobe pulmonary venous flow with twodimensional or pulsed Doppler echocardiography. Of these, the left lateral apical 4-chamber view can be applied as standard view, because the pulmonary venous flow and transmitral flow could be recorded in this view simultaneously with small sampling angle. The velocity pattern of pulmonary venous flow demonstrated two forward waves in 19 of 20 dogs examined, with one peak occurring during ventricular systole and another during ventricular diastole. A reversed flow during atrial contraction was also seen in 11 dogs. In the two forward waves, the mean peak velocity and velocity-time integral of ventricular diastolic forward flow were significantly higher than those of systolic forward flow (46.49 ± 6.79 vs. 31.13 ± 4.92 cm/s, p<0.0001 and 8.18 ± 1.84 vs. 5.14 ± 0.82 cm, p<0.0001, respectively). The deceleration time of diastolic forward flow shortened with the increase of heart rate (r= 0.87, p<0.0001). Pulmonary venous flow in dogs can be observed under transthoracic two-dimensional or pulsed Doppler echocardiography. -KEY WORDS: canine, pulmonary venous flow, pulsed Doppler, transthoracic echocardiography.J. Vet. Med. Sci. 60(3): 333-339, 1998 available imaging planes and the techniques for examination, and to confirm the anatomic location of pulmonary veins on the imaging plane, finally, to record the characters of the pulsed Doppler pattern of PVF in normal dogs. MATERIALS AND METHODS The available imaging planes and the anatomic validation in two-dimensional echocardiography:Five mongrel dogs weighing 8 to 11 kg (mean weight 9.30 ± 1.52 kg, 3 males and 2 females) obtained from an animal shelter were determined as healthy based on the results of routine physical examination and hematology. No evidence of cardiac or pulmonary abnormality was seen under either auscultation or two-dimensional echocardiography. These dogs were examined in the right or left lateral recumbency under consciousness with two-dimensional and color Doppler echocardiography by an ultrasound instrument (EUB-565A; HITACHI Medical Corporation) and a 5 MHz sector scanning probe (EUP-S32; HITACHI Medical Corporation). The presumed imaging planes for observing the simulacrums of the pulmonary vein were obtained. Then, all five dogs were prepared for lateral thoracotomy.The anesthetic protocol included premedication with atropine (0.02 mg/kg intramuscular) and droperidol (0.5 mg/ kg intravenous), induction with pentobarbital sodium (20 mg/kg intravenous), and maintenance with Halothane (1%-1.5%). Thoracotomy was performed in two dogs from left lateral and in three dogs from right lateral at the fifth or sixth intercostal space after routine aseptic preparations. Fr...

Effects of age, body weight, and heart rate on transmitral and pulmonary venous flow in clinically normal dogs

“…46 The finding of the dependence of DT E on BW is clinically important, because this variable is frequently used to obtain information on left ventricular compliance 9,18 as well as prognosis. 57,58,c Reference values for DT E in dogs do not mention BW, 4,12,18 yet the BW may vary widely in dogs with heart disease. Prolonged DT E with increased BW may partially be explained by the correlation between BW and HR or BW and LVSF.…”

“…13,41 All patterns of pulmonary venous flow were recorded from the pulmonary vein of the left caudal lung lobe. 12 Doppler echocardiographic evaluation of optimal sample volume position and alignment with flow was guided by simultaneous display of realtime 2-D echocardiographic images. Oblique or angled views were avoided.…”

“…4,5 Pulsed-wave Doppler echocardiography of transmitral flow and pulmonary venous flow has been used to assess left atrial and left ventricular filling and, indirectly, left ventricular diastolic function in clinically normal dogs. 4,[6][7][8][9][10][11][12][13][14][15][16] Reasonable correlations have been found between Doppler-derived indices of diastolic cardiac function and invasively derived diastolic variables (diastolic pressures, the time constant of ventricular relaxation, ventricular compliance, and myocardial stiffness) in a number of studies in dogs. [6][7][8][9][10][11]17,18 Therefore, Dopplerderived indices of left ventricular diastolic function can be considered useful for the noninvasive evaluation of diastolic events in dogs.…”

Effects of Respiratory Cycle on Pulmonary Venous Flow and Cardiac Cycle on Pulmonary Venous Diameter of Dogs: A Transesophageal Echocardiography Study.

“…It has been thought that both mechanisms, that is, increased afterload and diastolic pressure would result in a reduction of pulmonary venous return to the left heart. However, in our previous experiment there was no striking influence of respiration on the wave form of the PVF in conscious dogs with quiet breath [2]. The PVF in human also showed only minimal changes during quiet respiration in the studies reported by Smallhorn et al [12] and Klein and Tajik [5].…”

A Clinical Study on Velocity Patterns of Pulmonary Venous Flow in Canine Heartworm Disease.

“…Moreover, such a method is not always easy to use in a clinical setting. Conversely, a transthoracic wall approach without anesthesia may have advantages for the observation of the velocity pattern of PVF by Doppler echocardiography in dogs [1,9]. In the present study, we have, therefore, attempted to establish a method of observing Hitachi Medical Corporation) for TEE, and an electro sector type transducer (5 MHz; Hitachi Medical Corporation) for TTE.…”