Need opinions about lead implant location

I'm 59 years old . I have been diagnosed with RBBB and have had a pacemaker for 11 months. It was implanted because of 2:1 heart rate drops during exercise. I changed to a new Cardiologist 3 weeks ago because the first one never did adjust my PM to stop the 2:1 drops. The new Cardiologist reprogrammed my PM and I think that the drops have stopped; but, now during exercise, nearly every time around 145-155 bpm, I experience a jolt-like (or a skipping-like) sensation in my heart, and next, my breathing becomes difficult and I soon have to stop my running exercise activity because of shortness of breath- it feels out-of-sync. Next, my heart rate remains at about 125-135bpm for 1.5 to 3 hours, as monitored by my heart rate monitor. This has happened 3 times in the last 3 months (twice last week). My new Cardiologist suspects SVT (supra-ventricular tachycardia) and I will soon have a Holter monitor to confirm the SVT. Does anyone here agree that these symptoms sound like SVT? I've had HR drops during running for the last 35-40 years; but have had the prolonged high heart rates following exercise only since having the PM implant. My current Cardiologist said to me that the atrial lead of my dual lead PM is implanted very close to the ventricle. My dual lead PM has one atrial lead and one ventricular lead. Could this close proximity of the atrial lead to the ventricle be the sole cause of my SVTs? I plan to ask my new Cardiologist (EP) this question; but am curious about your opinions here. Best regards. Thank you.

5 Comments

rate drops

by Tracey_E - 2013-12-29 08:12:22

Yes, the atrial lead in the wrong spot can cause problems. Sorry, I know nothing about that so I can't help there but! I have av block, svt, and sudden drops during workouts so I have lots of thoughts on settings. My programming was tricky but with persistence we got it so I can work out hard and feel great. Most drs do not have many active patients so this may be something they've never dealt with before and they are easily stumped. My St Judes rep has other active patients and was able to research with other reps, I credit him more than my dr with getting my settings where they are now. My doc and the other techs who sometimes see me are afraid to touch my settings, lol, only my main rep makes adjustments. Fortunately he sees me as a challenge rather than a pita!

The treadmill was more help than the Holter, so you might want to ask about it, esp since your problems are all exercise related. Run with the pm computer hooked up, see exactly what happens, tweak the settings, try it again to see if it helps, repeat (because it will take several tries to get it right).

Upper limit- sounds like you are set at 155. It should be able to go to 180. There is one model out that limits at 150, one at 220, pretty much everything else out there has a maximum upper limit of 180. Is there a reason they don't want you higher than 155? If not, ask them about going higher. That may solve the problem.

Rate drop response (I think that's what it's called!)- they don't always turn this on. Sometimes when working out, my atrial rate would tank at random. This was a surprise we found on the treadmill. We assumed my only problem was av block and therefore all the sudden drops were from ventricular pacing settings, but turns out sometimes my hr just drops on its own. They set it to kick in with atrial pacing when this happens. It limits how quickly the heart rate comes down so if it comes down too quickly, it paces and keeps the rate up.

Something to ask- there is a safety feature on the pm intended to keep our pulse from going super fast during atrial fibrillation episodes. If your atrial rate goes higher than your upper limit (155?), the pm thinks you are in afib and suddenly cuts back how fast it paces the ventricle, putting us into an artificial block. This is great if you are in afib, instant end of work out if you are just exercising! This can be turned off if you have no history of afib. Normally this setting is an artificial 2:1 block. I pace every beat so my hr would drop in half. If you are not pacing every beat, 2:1 means on average every other beat, your rate may be faster when/if this kicks in so you may be experiencing this.

After turning the above off, working out got easier for me but sometimes my atrial rate still took off (svt) and would get higher than 180 (my max). Now, my ventricles would pace at 180, which feels a whole lot better than suddenly pacing at 90, but still not good when your atria is doing 200. I would stop, breath deeply and wait for my rate to come back down to 160 or so, then get back to it. This worked for a year or so but then happened more and more often. I got frustrated with the constant stops and tried a low dose beta blocker. Now my rate rarely gets over 155 so no more issues with bumping the upper limit.

Beta blockers also make the heart beat less hard so it affects my stamina somewhat, but I'm still able to do what I want. Not a perfect solution, but it is the best we can come up with and I can make it through a Crossfit class. I may be slow and the last one done more often than not, but I can finish so I'll take that and be happy.

Heart rate monitors are notoriously in accurate with us, always count manually when you think something is going on. They can pick up pacing spikes as beats and count too high, or they can miss beats from interference from the pm and count too low.

Hope this helps! Sounds like you have a dr willing to work to get it right, that's the first step. It frustrates me to see so many drs write patients off, tell them they are as good as they are going to get so live with it. For some that is the case, but the right settings can make a huge difference.

OPinions are Like Noses...

by donr - 2013-12-29 09:12:08

...Everyone has one, & some are uglier than others., Here's mine. Far mor limited than Tracey - she's an expert on this kind of thing - BUT:

How many leads do you actually have? I've read your post three times & I'm still not sure. You state that: 1) you have a dual chamber PM; 2) It is SUPPOSED to have two leads; 3) The Atrial lead is planted close to the Ventricle. This sounds like the surgeon tried to skimp on leads by planting only ONE of them, but doing it close to the Ventricle. Never heard of such a thing before. Please tell me that you do, indeed, have both leads planted.

If you are really intent on monitoring your HR, Get a finger tip Pulse Oxymeter. It senses pulse by using a red light that transmits through a fingernail & measures the pulses by the change in the reflected/absorbed light & will not be spoofed by any electrical activity of the PM. Also gives you blood Oxygen saturation at the same time. They cost under $50 on Amazon w/ enough bells & whistles to satisfy ant HR geek.

Don

answers...

by chip j - 2013-12-29 12:12:24

Thanks for the input.

I have 2 leads implanted, one in the right atrium (but, located very close to the right ventricle). And a second lead implanted properly in the right ventricle. Don, I re-read my first post above and it was ambiguous about the leads!

My HR limits are set at 50 and 170. RR is turned off. The first EP tried RR set on and it only caused other problems for me and never helped me during exercise.

I have confirmed, using a small wrist-type blood pressure cuff, during exercise that the heart rate displayed on my Polar during this SVT(?) event is accurate. My blood pressure is also relatively low during these events, about 98/68. When the SVT(?) event suddenly ends (several hours after exercise has stopped), my HR drops about 50% within seconds, back to about 65-75 bpm. And, my BP immediately returns to about 125/70.

I wear Garmin and sometimes, also a Polar HR monitor simultaneously. The Garmin and Polar both display about the same HR (within about 2-4 bpm) until my heavy, uncomfortable breathing begin about 145-150 bpm. Then, the Garmin either blanks out or begins showing very erratic numbers, usually on the extremely low side, sometimes followed by upward spikes. The Polar HRM shows a nearly consistent HR, displaying HR levels close to that when I first felt the jolt-like beat in my heart. On occasions when my HR stays high (125-145 bpm) for hours after I've stopped running, the Garmin eventually displays the same, constant high HR that the Polar displays. All 3 times that I've had the prolonged high HR following exercise, my HR has eventually dropped back to normal levels on its own, without any other intervention- but that can take 1.5 to 4 hours.

Tracy, I did feel written-off by my prior Cardiologist and the PM Rep. They knew that I had RBBB but never had a clue nor mentioned SVT. They even suggested "just go out and run, and don't wear your HRM." I got the impression that they thought my experience was mental. The current EP said that, before he reprogrammed it, that my very strong electrical wave in my atria was being counted twice by the PM (the PM "thought that your HR was well over 250-300" and, Tracy, as you mentioned above, the PM was going into a 2:1 block. My current(2nd) Cardiologist programmed around that and now I think that the 2:1 blocking has stopped. I think that the SVT events are my only problem now. I had a treadmill/EKG stress test on last Thursday. It only lasted 8 minutes and was only a fast walk. Of course, nothing unusual happened during that test. After driving home that day, I did a run and had the SVT symptoms at about 3 miles into my run. My HR stayed at 125 bpm for 2.5 hours, after I stopped running. I wish it had happened during the stress test that morning! But, I'm certain I can make it happen while wearing the Holter monitor, tomorrow.

Thanks again for the detailed replies. I sincerely appreciate your taking the time.

Svt

by Tracey_E - 2013-12-30 04:12:13

Once you rule out the pm settings or leads causing problems, when you are sure it's svt, then beta blockers may be your next thing to try. When the heart goes fast on its on, all the pm can do is watch. Svt is generally harmless but as your finding, it can keep us from getting a good workout. Good luck finding a solution.

Update...Ablation stopped my SVT

by chip j - 2014-03-30 01:03:11

Thanks again, Tracey.

I finally made it to my EP's office during an SVT event and it was diagnosed on EKG. My EP recommended an ablation for my AVNRT-type SVT. He said the SVT would probably become more frequent in the future. So, I decided to have the ablation. The procedure was successful and I haven't had an SVT since (about one month). I'm hopeful they stay away as long as I'm around :) .

You know you're wired when...

You have a $50,000 chest.

Member Quotes

I still feel great today and can’t stop feeling excited at my "new" life. Modern day miracles through medicine and electronic devices are amazing!