Dear Michelle,
Please don't worry about asking questions about this. As I always say to my families, it is more fun to work with parents who actually care about their children than those who seem as if they are less interested.
Although I don’t have access to all the information that I need about your son, I can make some inferences from the information that you have given me. I would just like to explain a few things for our other readers. His right bundle branch block (RBBB), which is an electrical conduction delay in the lower portion of the heart, is something that we often see after surgical closure of a ventricular septal defect (VSD). It typically does not cause problems, though, unless there is a more complex structural cardiac defect. He also had a patent ductus arteriosus (PDA), which is a blood vessel that all babies have in utero. It should close after the baby is born, but sometimes it remains open, especially in premature infants. In your son’s case, it was ligated, or surgically tied off. It also seems as if he has some mild stenosis, or obstruction, of the right ventricular outflow tract below the pulmonary valve. As long as it remains mild, it should not cause a problem.
I am not sure why his heart rate is ranging so widely. Sometimes we do see what is called sinus node dysfunction that can occur after cardiac surgery. The sinus node is the natural pacemaker of the heart, and is located in the right upper corner of the heart. It can be damaged when the heart is opened, if a suture is placed near it, if it is congenitally abnormal, or when a heart-lung bypass machine canula is put in the superior vena cava, which is the vein that drains the head, neck, and arms back to the right side of the heart. A specific type of sinus node dysfunction is called the bradycardia-tachycardia syndrome, or brady-tachy, for short. Bradycardia occurs when the heart rate is too slow, while tachycardia occurs when the heart rate is too fast. Brady-tachy syndrome can give alternating bradycardia and tachycardia for which patients can be symptomatic. Sinus node dysfunction can also give inappropriate sinus tachycardia, which is a fast heart rate that originates from the sinus node.
Other potential reasons for your son’s symptoms could include thyroid disease as well as an arrhythmia that originates in or near the sinus node. He does sound like he is definitely symptomatic with these episodes, no matter what it is. Usually, we say that persistence of symptoms greater than 15 to 20 minutes is reason to have it evaluated in the Emergency Department (ED). But, if he feels worse than usual, I wouldn’t wait that long to contact your doctor or go to the ED. It sounds like the evaluation is ongoing right now with the loop recorder at this point. Without knowing all of the details that I would need to be able to evaluate your son, I can’t say what his risk is of sudden cardiac death. Since they said that he does not have ventricular tachycardia (VT), that is certainly more reassuring. As well, heart rates of 217, while uncomfortable, are usually not life threatening; however, if your child’s heart function is diminished, then it could be a problem. Your cardiologist should be able to discuss not only the outcomes of his testing but also further plans for whatever evaluation and treatment he may need.
In the end, if he has this exercise intolerance and it is due to sinus node dysfunction, a pacemaker may need to be placed to help his heart rate be more normal. It may very well help his exercise intolerance, although I can’t say for sure without knowing his whole picture.
Finally, one other issue is a bit concerning. The fact that the flow at his PFO is bidirectional suggests that there may be either right ventricular dysfunction or elevated right ventricular pressures. I would recommend that you ask your cardiologist what his or her thoughts are regarding this finding. Besides this impact on cardiac function and his exercise tolerance, this could potentially play into his risk for arrhythmias, as well.
on 2 of his holter monitors they also stated something about having episodes of wander of the atrial pacemaker. I take his pulse for a full minute since there is a pause in his heart rate. this is very hard for me to count, but i finally got it down. the doctors told me that we have to count it for a minute we can't go by 15 sec, x's 4. he is short of breath when this happens, and he gets very tired after wards.(when it is fast) when he is slow, he comes close to passing out as he can without passing out and I have to carry him. by the time we get to the ER, he is better, thankfully we live 20 minutes away from the ER, and have a volunteer rescue squad, which responds quickly 18 minutes. I just need to know that he is okay.and he isn't gong to die due to this. I wished I could get a copy of his recordings and have them sent for a 2nd opinion to see and if it is worth a very expensive trip out of state. or am I just wasting my time as well as others.
Thank you for listening and trying your best to answer my question
Michelle
sorry but I have one more question an dI know I am a pain in the butt. however, his little heart rate can go anywhere from 42-over 200, when it is low he almost passes out once he has, his HR is all over you can count it and get one nice number (100) and then 5 minutes later get something like 185. i was wondering he gets tired of going short distances,he can not keep up with kids his own age (it is hard to tell in school since there are only 2 other kids in his class ) but I have seen younger kids go more then he does, my question is if they were to put in a pacemaker and set it so his heart can't go above or below a number say 60-120 and keep his heart in a regular beating pattern can this give him more energy? even his breathing gets really bad when he runs for a wee bit
Sorry for the questions, ?I just want to help him out I can't stand to see him trying to keep up and like I said before I am so afraid of loosing him
Michelle
You mentioned about RV pressure his in the past has been at 13mmhg but in Nov. 08 it went to 26 and from what I take it is normal and has to be much higher like n the 70's.
Thank you for your help and I know which way to head.
michelle