SVT question

[pops30]

Hello I'm a 30 year old man, 35 pounds overweight  ex smoker..
After a couple months of having these symptoms:

malaise,
lethargy,
mood changes, irritability,
tachycardia bouts with near syncope
waking at night with racing pulse and can't breath in

chronic heavy and dull chest pain
throbbing deep in upper central chest
general widespread chest pressure especially after an SVT
feeling too weak in the chest to take a full breath of air

My loop recorder found a SVT of 160 during my sleep (i woke up, couldn't breath, heart racing, in a panic..not the first time that happened)

During awake hours, it takes something to set off my SVT's.  Minimal excitement...anticipation for things good or bad....getting ready in a hurry to go places...Normal things I used to do that would get my pulse up, but except now it causes symptoms for some reason.   I have the symptoms listed above even when I'm not tachycardic...and I can't stress enough the symptoms above especially the heavy chest feeling and restricted breath feeling..it's a nasty feeling.

I am sure that my pulse used to get above 100 during periods of excitement/arousal, however only now that I have the above associated symptoms is even the mildest of tachycardia causing lightheadedness, predisposal to syncope,  and heightened anxiety.  I am just extremely sensitive to the slightest high pulse, it really makes me symptomatic even at 110 bpm, a forceful almost painful throbbing heartbeat it is during arousal, where as in my previous days I'm sure I could have this pulse without much fan fare.

I've been referred to an EP, and I'm scared of the heart cath ablation...Will they look closely for an EXTERNAL (outside the heart) source of tachycardia before the cath?  (ie- adrenal  anxiety infection etc), or is it normal to jump right into the cath?     (I can't take beta blockers due to my borderline hypotension)

[pops30]

Oh and by the way, I already did have a normal Echo...Does this rule out weak heart muscle?

THank you very much

[pops30]

When I say I can't tolerate a pulse of 110...I mean it makes me uncomfortable and lightheaded if this pulse happens at rest.

I can exercise and have a pulse of 160 without any shortness of breath or weakness.

Does this rule out a weak heart muscle or not?

Please follow up..even with a simple  yes or no  to weak heart muscle?

[Darcy Green Conaway, MD]

The first question I would pose to you is : are you sure you can't take beta blockers? it is very unusual for someone to be "borderline hypotensive", especially when they are 35 lbs overweight and an ex-smoker. Furthermore, even with a history of SVT you should not have problems tolerating heart rates in the 110's...unless your heart muscle is very weak. I would suggest an echocardiogram if one has not been performed and I think you should proceed with an EP evaluation if you are truly intolerant of beta blockers.