Any cardiologists out there?

[H2ODude]

Or for that matter heavy exercisers who've experienced this! I'm just blown away by what has happened (and I think it is a GOOD thing!). May be long story.

I've always been a fairly vigorous exerciser, running or biking, and engaging in heavy work (but was a desk jockey for the most part in my career). Even checked the marathon box, Grandfather Mountain M, did in little over 4 hours. Have no long term issues other than a slight heart murmur that has been baseline monitored with echocardiogram, pretty much dismissed as nothing to worry about.

Am currently 65 and over last few years BP has been creeping up, at annual physical GP said to get a monitor, watch it, and if it was consistently where he measured (143/90) to fill a scrip he gave me for metoprolol, a beta blocker. Started it three days ago and noticed almost immediate reduction, down to 130 over 90 or less, and resting HR dropped from high to low 70's (my HR always has been high). So cool, doing what it should, and I had noticed on web before I got it that it could lower HR.

I've used Garmin HR monitor running and biking and Expresso bike at Y that is pretty rigorous recording HR and wattage. I consistently get HR to mid 160's, average maybe 150 or so over 50 minutes of pretty rigorous activity. At Y the bike says 150 watts is usually my average, so you can pretty much gauge output vs HR.

Today was the first day I've been to gym since started the metoprolol, didn't expect anything out of ordinary or to even look for any changes. Got near end of 50 minutes of not a super vigorous, but pretty hard ride averaging 140 watts. Looked at monitor and said HR was 110. I assumed that could NOT be right, machine must be off. As soon as got done did a manual check of pulse, and it was spot on. Checked web record of my rides and for similar average wattage I usually average HR of 140 or so. Today it was 105.

I asked the nurse there about it and she said yes, beta b will reduce HR but she was not aware of such a reduction while under heavy exercise. I had NO feeling of being stressed or in any way different from prior rides like this. How can my heart possibly sustain my body under identical exercise yet beat 25% less? Engineer here, this is a positive displacement pump so what is going on? Lower BP less back pressure? Somehow more efficient? I've never had a cardiologist but this makes me want one just to answer these questions! I've looked around web but don't see anything relative to the drugs and HR under exercise but I'm sure it's out there. I can only assume this phenomena is a good thing, I'm just incredibly astonished at how a drug can have this effect.

Anyway, anyone have any knowledge of this or experience directly with it? Thanks!

 

[Winemaker]

I take 20mg of lisinopril and 2- 3.125mg coregs a day for the last 5 years and cannot get to my target HR ever. I just pedal my butt off.

 

[Walt34]

I'm also on metoprolol and experience the same effect. When the doc did the stress test a month ago he took me off it for a day for the test and I got the heart rate up to 155, a rate that I never, ever, see at the gym. It is rare to see over 125 even though I'm pushing hard. Staff at the gym, all with various certifications, tell me this is normal with the meds I'm on.

 

[MRG]

I was on Aetenol, a beta blocker, for many years, they slow the heart. I wasn't physically active back then but I don't believe it would go to peak. Actually any time it was measured it was 55. I recall doing a stress test and it took forever to get close to where they wanted it.

They took me off of it because after a while my resting heartrate got down in the 30's. That was in the ER, with all kinds of folks running around trying to figure out why I was ready to pass out. So yeah that sounds normal. Of course I'm no DR. so my advice is worth what you are paying.

 

[W2R]

Metoprolol INSTANTLY transformed my BP from 138/98, to a very consistent 105/65 or so. It's been utterly ideal since my internist put me on it back in 2009. Great stuff!!!

My heart rate has been around 95 or so for my whole life. It went down to the low 70's when was first on metoprolol, but since that time it has increased to the mid 80's. I guess my heart just wants to beat fast. But my BP has stayed nice and low.

Oh, and to answer your question, yes, my BP and HR both stay lower at the gym than previously, too. Here's a caution: About a year ago I fainted at the gym, after not doing a cool down following exercise. I think the combination of the metoprolol and not doing a cool down probably caused it. So, I always do a cool down now.

 

[NW-Bound]

...How can my heart possibly sustain my body under identical exercise yet beat 25% less? Engineer here, this is a positive displacement pump so what is going on? Lower BP less back pressure? Somehow more efficient?...

Engineer here too, and no medical expert.

Is the heart a true positive displacement pump? I read that many drugs for circulatory problems dilate the blood vessels in order to reduce hypertension. That should hugely reduce the load on the heart, but a mechanical pump would still have to maintain the same speed in order to move the same volume of fluid.

So, I conclude that the heart is not a positive displacement pump. Perhaps it's because of its elastic wall, or that it does not contract all the way when there's back pressure. Hence it delivers less volume when the arteries are constrictive.

 

[6miths]

I''m not a cardiologist and don't even play one on TV but I often tell students that the heart is just a stupid pump but this is not really true. It turns out that at least two factors might account for what you are seeing. The first would be what you have describe with the reduction of pressure that the pump is working against (medically this is termed 'afterload' which is pretty much equivalent to BP in most cases). beta-blockers don't directly effect BP so this wouldn't be the likely mechanism (alpha-blockers would but aren't commonly used and ACE inhibitors and some calcium channel blockers do and are commonly used but generally agents that cause blood vessels to relax usually cause a reflex increase in heart rate). The main reason is something called the Frank-Starling Law. beta-blockers slow the heart by antagonizing the effects of adrenalin and noradrenalin in the heart. This allows more time for the left ventricle to fill. The Frank-Starling Law states that the more full the ventricle is, the more forcefully it will contract meaning that even though HR is slower the output or stroke volume (SV) is increased and compensates for the lower rate. This is one of the reasons why endurance athletes, who will develop large hearts due to training will have very low resting heart rates and relatively low heart rates even when demand is increased.

 

[Bamaman]

And some long distance runners and bicyclists that have the slow, hard hitting hearts sometimes have fatal heart problems.

I had a friend that owned a large bicycle shop in Atlanta and rode mega-miles on road trips. At 40 years old, he had the "big one." Fortunately, he received great care and is still with us.

Those world class athletes can sometimes have a shorter lifespan than us getting less vigorous exercise. And the problem is they don't know whenever it'll hit--and don't know their limitations.

 

[H2ODude]

Thanks for the observations and insights. I get that the heart isn't really a positive displacement pump since the walls are flexible and there is SO much going on as far as control, timing, exertive force on the walls etc. But still, to do for me with 25% less beats and produce same output (wattage) is to me a real head scratcher. I guess I'm concluding that this drug somehow makes my heart 25% more efficient? I really didn't want to sign up for my first "forever" prescription as it implied to some degree the start of the "slide." However, if this not only lowers BP (an obvious positive) but makes the old ticker more efficient, I'll take it!

 

[6miths]

It doesn't really make it more efficient but it isn't going to have significant negative effect especially if your heart itself is in good shape. Exercise is a good thing on it's own as it will have the effect of lowering BP and will mean less work for the heart which is I suppose somewhat counter-intuitive. One of the potential side effects of beta-blockers is fatigue due to the inability of a deconditioned heart to increase stroke volume in response to a slower heart rate. Doesn't sound like you have this problem.

 

[ls99]

A bit of curiosity on my part.

My guess is that elevated blood presssure is the body's (system's) adaptation to some malfunction. A pill to control the pressure (by whatever chemical means) will limit the maximum performace of the system, by limiting the ability of the blood volume moving about, to deliver oxygen and whatever else the system needs and transport stuff to be removed under previeusly handled normal, high or maximum load. Light loads will be handled easily with symptom treatment.

The question in my mind is what malfunction caused the pressure to rise and how could that be remedied.

Can root cause be identified? Then corrected in addition to just treating the symptom. And eventually get off symptom control treatment.

BTW at 69yo my BP typically runs 128/70.

 

[Meadbh]

A bit of curiosity on my part.

My guess is that elevated blood presssure is the body's (system's) adaptation to some malfunction. A pill to control the pressure (by whatever chemical means) will limit the maximum performace of the system, by limiting the ability of the blood to deliver oxygen and whatever else the system needs and transport stuff to be removed under previeusly handled normal, high or maximum load. Light loads will be handled easily with symptom treatment.

The question in my mind is what malfunction caused the pressure to rise and how could that be remedied.

Can root cause be identified? Then corrected in addition to just treating the symptom. And eventually get off symptom control treatment.

BTW at 69yo my BP typically runs 128/70.

Sounds great, except that most adults with hypertension have no identifiable cause. Investigation of root causes is more productive in children and very young adults.

 

[ls99]

Hmmm, I did not know that hypertension has no identifiable cause.

Sounds weird. Seems to me there must be reson(s) for hypertension. I realize the human plumbing is far more complicated than say hydraulic lift, yet pressures have to have reasons or causes for changing from "normal".

One guess would be dehydration, changing total blood volume. Unlike a hydraulic lift, the human system does not seem to have a vented expansion tank.

Maybe in time cause will be discovered. I am sure there are millions who would like to get off the meds.

 

[6miths]

There are many potential causes but the vast majority have 'essential hypertension'. Certainly there are risk factors. As we age, our aorta becomes stiffer and this leads to systolic hypertension (the first number) as the elastic aorta is less able to expand in response to the surge of volume out of the heart. The process is greatly accelerated by atherosclerotic processes. As well, people who are overweight have many more miles of blood vessels associated with the extra adipose tissue. Some people also just have vessels that seem to be more sensitive to the substances that make them constrict (adrenalin, noradrenalin, angiotensin II, etc) or less sensitive to substances that make them relax (prostacylin, nitrous oxide, etc). So far, we haven't figured essential hypertension out but it looks like the malfunction is in the vessels themselves or production or response to the substances that control their diameter and therefore the resistance to flow.

 

[NW-Bound]

Yes, that "essential hypertension" is tough. It's just old age, though some people are more affected than others.

What it means is none of us will get out alive. The human body is programmed to have a limited lifespan, and all we do with medicine is to stretch it a bit more.

Time for some gloomy music.

 

[6miths]

Fabulous gloomy music!

 

[NW-Bound]

The song sinks in more if you compare the look of band members in the above video with their younger selves. I do not know when these videos were made, but they have gotten older still.

 

[Winemaker]

My doctor says my meds are strictly preventative as they smooth my artery walls. My catheterization 8 years ago revealed no defaults, but confirmed that I had the biggest a$$hole boss!

My BP had been 130/90 ever since I was a teenager trying to get into the Air Force Academy, when they monitored my BP for a month.

I'm 115/75 now, retired, and free of the a$$hole!

 

[Bestwifeever]

DH's high blood pressure might not have been caused by hypothyroidism, but when the latter was diagnosed and treated with Synthroid (twenty years now of taking that), his high blood pressure was also alleviated and the doc stopped the beta blockers he had been taking. Here is an article on secondary hypertension: Symptoms and causes - Secondary hypertension - Mayo Clinic

 

[kcowan]

I take metaprolol 12.5 g morning and evening. They seemed reluctant to prescribe it. Any known side-effects by participants here?

 

[Meadbh]

DH's high blood pressure might not have been caused by hypothyroidism, but when the latter was diagnosed and treated with Synthroid (twenty years now of taking that), his high blood pressure was also alleviated and the doc stopped the beta blockers he had been taking. Here is an article on secondary hypertension: Symptoms and causes - Secondary hypertension - Mayo Clinic

The OP's family member has HYPERthyroidism (too much thyroid hormone). Your DH has HYPOthyroidism (too little thyroid hormone). They are opposites.

 

[Meadbh]

I take metaprolol 12.5 g morning and evening. They seemed reluctant to prescribe it. Any known side-effects by participants here?

Yes, there are dozens. Anything you fancy.

Common Side Effects of Lopressor (Metoprolol Tartrate) Drug Center - RxList

 

[Bestwifeever]

The OP's family member has HYPERthyroidism (too much thyroid hormone). Your DH has HYPOthyroidism (too little thyroid hormone). They are opposites.

Yes, I know that, but I am pointing out that there are secondary causes of hypertension. Sorry that I was not clear. So never mind.

 

[jcretire77]

Also curious if anyone has had any issues with lisinopril. Coincidentally I had a frozen shoulder during the time that I took it. Never before and never since.

 

[Meadbh]

Yes, I know that, but I am pointing out that there are secondary causes of hypertension. Sorry that I was not clear.

I'm sorry if my post offended you. My reasoning was that introducing HYPOthyroidism into the discussion may cause confusion for some readers.