I performed an echo on an obese 9 year old mn Chihuahua this am and had difficulty getting good images. The images were fuzzy and there was lots of lung interference. I was able to get 2D measurements on the trans LV views. The measurements were all normal except for mildly decreased LVIDd. The heart valves all showed normal morphology and movement. No cardiac masses or effusions were seen on RP and LP views. I was able to get sharper images with the patient in left lateral recumbency. The dog presented to the rDVMwith a history of making gurgling s
I performed an echo on an obese 9 year old mn Chihuahua this am and had difficulty getting good images. The images were fuzzy and there was lots of lung interference. I was able to get 2D measurements on the trans LV views. The measurements were all normal except for mildly decreased LVIDd. The heart valves all showed normal morphology and movement. No cardiac masses or effusions were seen on RP and LP views. I was able to get sharper images with the patient in left lateral recumbency. The dog presented to the rDVMwith a history of making gurgling sounds. Lateral chest view showed an irregular cardiac silhouette which was not visible on VD views. The rDVM was concerned about effusions or cardiac mass. I suspect that the rDVM is just seeing pericardial fat on the rads.
So, my questions are this:
1. Is it normal to have trouble getting good images on small (3kg) obese dogs with round chests? Any suggestions on how I could have improved the images (I tried both scanning the patient directly on the table and over a cardiac positioner pillow).
2. Do you use the reference values for ideal body weight vs. actual obese weight?
Comments
Hi!
I know these problems.
Hi!
I know these problems. Lat recumbency is mostly better. And if you reduce your dynamic range and increase the dynamic compression you will get more contrast. It is not only about the fat; If the patient is suffering from some lung disease, e.g. interstitial lung disease/fibrosis, you will hardly get really clear images. And try to place the transducer a little bit more towards the sternum. You´ll get somehow tipped views but a better acoustic window
Even though it´s better to use reference values according to the ideal body weight, I would not stick to tables. I have certain rules to see if the patient is suffering from hemodynamically significant cardiac disease or not. These are based on a right 4chamber view and include:
If the interventricular septum is straight
if the inter-atrial septum is straight
if the enddiastolic free wall fits 3.5-4.5 times into the left ventricular diastolic cavity
if the right ventricle is 1/3 of the left
if the right free wall is 1/2 of the left
if the right atrium is smaller than the left one
then the dog is very, very, very unlikely to have clinically significant heart disease, because there´s no evidence of volume or pressure overload.
In your case you had a decreased LVd: This can be due to concentric hypertrophy (subaortic stenosis which would cause a murmur, significant systemic hypertension which is rather rare in dogs) or decreased preload (some degree of dehydration).
Summarizing: You are not alone with the problem getting good images in fat dogs with respiratory problems 🙂 Decrease the dynamic range and increase compression to get a better contrast; do it in lat recumbency.
And: Don´t care too much about millimeters. A heart that causes congestion has usually a huge left atrium and at least moderate LV volume overload.
If you´d like to discuss the rads, just post them, I´m looking fwd to seeing them.
Best regards!
Peter
Hi!
I know these problems.
Hi!
I know these problems. Lat recumbency is mostly better. And if you reduce your dynamic range and increase the dynamic compression you will get more contrast. It is not only about the fat; If the patient is suffering from some lung disease, e.g. interstitial lung disease/fibrosis, you will hardly get really clear images. And try to place the transducer a little bit more towards the sternum. You´ll get somehow tipped views but a better acoustic window
Even though it´s better to use reference values according to the ideal body weight, I would not stick to tables. I have certain rules to see if the patient is suffering from hemodynamically significant cardiac disease or not. These are based on a right 4chamber view and include:
If the interventricular septum is straight
if the inter-atrial septum is straight
if the enddiastolic free wall fits 3.5-4.5 times into the left ventricular diastolic cavity
if the right ventricle is 1/3 of the left
if the right free wall is 1/2 of the left
if the right atrium is smaller than the left one
then the dog is very, very, very unlikely to have clinically significant heart disease, because there´s no evidence of volume or pressure overload.
In your case you had a decreased LVd: This can be due to concentric hypertrophy (subaortic stenosis which would cause a murmur, significant systemic hypertension which is rather rare in dogs) or decreased preload (some degree of dehydration).
Summarizing: You are not alone with the problem getting good images in fat dogs with respiratory problems 🙂 Decrease the dynamic range and increase compression to get a better contrast; do it in lat recumbency.
And: Don´t care too much about millimeters. A heart that causes congestion has usually a huge left atrium and at least moderate LV volume overload.
If you´d like to discuss the rads, just post them, I´m looking fwd to seeing them.
Best regards!
Peter
What I do in fat dogs and
What I do in fat dogs and bulldogs is scan form the sternum/costochondral junction and lean them on the sternum in right lateral 45 degree recumbency even leaning them off the table or just sit their sternum in the hole of a cardiac positioner. this will keep artifact out of the way using the good ol’ 9.8 m/sec gravity componenet:)
What I do in fat dogs and
What I do in fat dogs and bulldogs is scan form the sternum/costochondral junction and lean them on the sternum in right lateral 45 degree recumbency even leaning them off the table or just sit their sternum in the hole of a cardiac positioner. this will keep artifact out of the way using the good ol’ 9.8 m/sec gravity componenet:)