Is using the Aneros while lying on the left side dangerous?

I have been using the aneros for almost 2 years and lie down on my left side most times using the device. I have had no heart issues using it. But let me be clear, I haven't had any orgasms using it yet, just some good feelings. Not sure why your left side would be any different than your right

@Spanishguy69 If possible, are you able to quote the section in the Multi-Orgasmic Man? I'm sure this would be beneficial to other Aneros members.

The section titled "The Big Draw", has a list of Cautions.
One of which is as stated.

Strange though.

"In the beginning, do not lie on your back during these exercises, since the rising energy may stick in
your chest and cause pain. At first, sit, stand, or lie on your side. If you lie on your side, always do so
on your right side. (Lying on the left side puts too much strain on your heart.) Once you master these
exercises, you can do them in any position. Also, never place any objects (such as a pillow) under
you while lying on your right side, since this will bend the channel of energy and can cause back..."

I'm not sure I can believe it, other than some supersticious mumbo jumbo....

Is using the Aneros while lying on the left side dangerous?

The simple answer is probably NOT.

I read in the multi orgasmic man, that lying on one's left side during Aneros use is too strenuous on the heart,...

First, I don't recall reading Mantak Chia specifically referring to Aneros use in his book, second, while Chia is very knowledgeable and has good wisdom to share, he is a human being who may be holding inaccurate beliefs about particular physical operations of the human body. When discussing metaphysical topics there is little definitive proof available to substantiate many claims/beliefs.

...is this something anyone else here is concerned with or had problems with?

IMHO, NO, I've been reading this Forum's posts for more than 9 years and can not recall any claims for heart related distress due to body positions whilst using Aneros devices. Good Vibes to You !

On page 37 of 105 under the section "Position Yourself"

There is no way lying on your side puts strain on your heart. Ridiculous.

Darwin

The section titled "The Big Draw", has a list of Cautions.
One of which is as stated.

Strange though.

"In the beginning, do not lie on your back during these exercises, since the rising energy may stick in
your chest and cause pain. At first, sit, stand, or lie on your side. If you lie on your side, always do so
on your right side. (Lying on the left side puts too much strain on your heart.) "

@rumel is right, Mantak Chia is very knowledgeable but in this case, he might be cautionning the individuals who may have hearth conditions. Under some of these conditions, the heart is pumping at a fast rate and his statement might be some sort of a disclaimer. If you notice, he starts his paragraph with "In the beginning...".

This book is a good one but it is a collection of theories and opinions and you need to treat them as such.