Echo vs Muga

Hi Dr.Rich

Your advice last time really helped clarify what we needed to do. Last time when I posted my mom's echo gave a EF reading of 30-33% (done in Jan 2012). So, we scheduled to get a CRT-D implanted in June. A week before the procedure the electrophysiologist conducted a MUGA test. The MUGA test showed the EF at 48%, and the electrophysiologist told us the device is no longer necessary. While we are happy the EF has drastically improved, we are concerned with the accuracy of test. Since there is such a large discrepancy between the two tests done 6 months apart ( she has been on HF medication since Nov 2010, and started out with a 15% EF), we are not sure which test is giving us the accurate reading. I would really appreciate your advice on which test we should follow in order to determine if my mom needs a CRT-D or not.

Thank you,
Vik

[Jonathan D. Rich, MD]

Hi Vik,

Welcome back to the forum.

There are several ways to calculate an EF.  Echo is the most common but MUGA, MRI, ventriculogram during cardiac cath, etc can all provide generally reliable EF calculations.

A well performed MUGA test is often fairly reliable.  Sometimes the images with Echo can be suboptimal and contrast is needed to truly see the heart walls sufficiently well to make a reliable EF calculation.

Frankly, at the end of the day, I would trust your mom's physician.  Electrophysiologists implant ICDs and pacemakers for a living and they believe in them.  The fact that the EP doc is advising against it at this time suggests that your mom may not need it.  There is no harm in repeating an echo if this would provide you peace of mind but you may find yourself going back and forth with this "dilemma".

I would move forward following the EP doc's advice.  If in the future a repeat echo (or MUGA) suggests a deteriorating EF and CRT is now being recommended then I would pursue that at that time.

I know this can be confusing but I suggest you follow the cardiologist's advice.  If you do not trust this cardiologist, then I would seek a 2nd opinion.

Best,

Dr. Rich

[vik45]

Thanks again, I really appreciate your input.