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ben's mom
07-12-2007, 06:20 PM
HI all,
We have just come from taking our 6 year old son to see a second pediatric cardiologist at Sick Kids in Toronto (Dr. Lee Benson). He thinks it may good for Ben to go on Beta blockers.
My son is currently without symptoms and is at the higher end of severity of HCM (Benson's words). He has no obstruction. His original cardiologist does not recommend beta blockers at this time.
My question is this: what does the research say about children (under 10), with non-obstructive HCM taking Beta blockers? Why does he need to take them if he has no symptoms?
Please someone point me in the direction of some hard data (journal articles, etc.)
Confused here in Toronto :)
Sara

Cynaburst
07-12-2007, 08:41 PM
You might want to call the office and have a conversation with Lisa about this issue. I am not sure how much hard evidence there is to go on.

I do know that Brigham and Women's in Boston is currently doing a study on genetically positive kids by giving them a calcium channel blocker to see if it keeps them from developing hypertrophy and/or symptoms.

The thing is that beta blockers help relax the heart, and may help keep things from worsening in the future but I don't think there are any guarantees. If the drugs are well tolerated, there isn't really a downside as beta blockers don't have long term negative effects. On the other hand, it is your child, and you don't want to give them any drugs they don't have to take.

I think you should do your homework and make an informed decision which is what you feel the most comfortable with.

Cynaburst
07-13-2007, 01:51 AM
Brownie, a member of the forum, found this article and sent it to me in a PM. Here it is for those who are interested:


A cohort study of childhood hypertrophic cardiomyopathy: improved survival following high-dose beta-adrenoceptor antagonist treatment.
I Ostman-Smith, G Wettrell, T Riesenfeld
Department of Pediatrics, John Radcliffe Hospital, Oxford, United Kingdom.

OBJECTIVES: The study analyzed factors, including treatment, affecting disease-related death in patients with hypertrophic cardiomyopathy (HCM) presenting in childhood. BACKGROUND: Previous smaller studies suggest that mortality is higher in patients with HCM presenting in childhood compared with presentation in adulthood, but these studies have all originated from selected patient populations in tertiary referral centers, and reported no significant protection by treatment. METHODS: Retrospective comparisons of mortality were done in total cohort of patients presenting to three regional centers of pediatric cardiology. There were 66 patients (25 with Noonan's syndrome) with HCM presenting at age <19 years; mean follow-up was 12.0 years. RESULTS: Among risk factors for death were congestive heart failure (p = 0.008), large electrocardiogram voltages (Sokolow-Lyon index p = 0.0003), and degree of septal (p = 0.004) and left ventricular (p = 0.028) hypertrophy expressed as percent of 95th centile value. The only treatment that significantly reduced the risk of death on multifactorial analysis of variance was high-dose beta-adrenoceptor antagonist therapy (propranolol 5 to 23 mg/kg/day or equivalent; p = 0.0001). Nineteen out of 40 patients managed conventionally (no treatment, 0.8 to 4 mg/kg of propranolol, or verapamil) died, median survival 15.8 years, with no deaths among 26 patients on high-dose beta-blockers (p = 0.0004); survival proportions at 10 years were 0.65 (95% confidence interval 0.49-0.80) and 1.0, respectively (p = 0.0015). Survival time analysis shows better survival in the high-dose beta-blocker group compared with the "no specific therapy" group (p = 0.0009) and with the conventional-dose beta-blocker group (p = 0.002). Hazard ratio analysis suggests that high-dose beta-blocker therapy produces a 5-10-fold reduction in the risk of disease-related death. CONCLUSIONS: High-dose beta-blocker therapy improves survival in childhood HCM.

mantrashak
07-13-2007, 09:12 AM
I don't have any scientific data. All I can go on is my own personal experience, feelings and education. And right now, my feeling is that beta blockers are not necessary if you're asymptomatic.

My condition was similar to your son's when I was that age too. I was kept under review, and had a period of investigations when I was 5 years old and again when I was 19. I was first prescribed beta blockers when I was 19. And subsequently chose not to take them. In my mid-30s I talked it over with a specialist. His advice was - get an ICD to avoid sudden death, take drugs to relieve symptoms. He reckoned there's no evidence to support the idea that drugs reduce hypertrophy, stop it getting any worse or prevent sudden death.

I'm 39 next month. Still no ICD, still no drugs. But healthy, happy and still reasonably asymptomatic despite the HCM I've lived with all my life!!

ben's mom
07-13-2007, 02:10 PM
Re: the study that was mentioned. Thanks for this study. However, there is no mention of whether these participants were symptomatic and/or obstructed. Further, almost one third of the subjects had Noonan's syndrome...I am not sure what this condition is but my son does not have it....Need more data! Sorry for being so demanding but I need to know I am making well-informed decision here....

Re: mantrshak...I appreciate your perspective....
Thanks
Sara

mflanagn
07-13-2007, 02:48 PM
My kids have been on a beta blocker since birth. They were assymptomatic for a few years, then of course developed symptoms and had surgery. Since surgery they have been assymptomatic, but continue on beta blockers. I myself would not stop. It is helping their hearts from getting thicker because it relaxes the strength of the beating. We have experienced no ill effects from this medication and it is relatively cheap with insurance. They take one extended release capsule daily.

macbeth
07-13-2007, 03:10 PM
My son was first diagnosed in 1990 with non-obstructive HCM. He was asymptomatic, as were his sisters, who in subsequent years were diagnosed from echocardiogram results. I've had a strong interest in this topic, and I can only share what we've been told by the pediatric cardiologists over the years.

We've worked with several pediatric cardiologists, and only one of them was willing to say that beta-blockers or calcium channel blockers had any direct effect on the progression of HCM. The particular doctor who did published a paper in the early 1980's saying that calcium channel blockers slow the progression of the disease. The other cardiologists said (and continue to say) that they are not aware of any valid epidemiological studies of the effects of those drugs on HCM patients. They were familar with the 1980 paper, and discmissed it, saying that the study was flawed. (One of them was listed as a co-author on the paper, and she said that she regretted that it had been published.)

At the same time, these same cardiologists have said that there is solid evidence that beta-blockers and calcium channel blockers have had a significant effect on the quality of life and survival rates for pediatric cardiology patients as a whole. They further say that HCM is relatively rare and, at least up until February of this year (when I last spoke with them) that no HCM-specific studies had been done. All have said that they see direct evidence of the benefit of the drugs in individual cases, and that they would be very surprised if these benefits didn't extrapolate to better quality of life and survivability for HCM patients as a whole. We have met no cardiologist who thought that prophylactic beta-blocker or calcium channel blocker treatment was inappropriate. Most strongly recommended it.

Regarding why these drugs are prescribed for asymptomatic children, these are the reasons we were given. HCM is a disease that occurs at the cellular level. The disease can exist, and progress for some time, before overt symptoms become apparent. Some individuals have the disease and never become symptomatic. Other develop symptoms at various points in time. The actual diagnosis of HCM depends on diagnostic tests, such as echocardiograms or MRIs. Reliance on symptoms can be misleading.

One of the effects on the heart of HCM is scarring due to inadequate blood flow. The scarring leads to a build up of scar tissue, and problems conducting electrical signals in the heart - this leads to arrythmias of various kinds. Furthermore, in an untreated heart, the scarring further restricts blood flow and the ability of the heart to pump, and the amount of scarring can accelerate over time.

One cardiologist likened it to a hand squeezing water out of a sponge. His analogy was that untreated HCM hearts, in effect, squeeze so hard that they reduce they flow of blood in the heart tissue itself, like all the water being squeezed out of a sponge by a clenched hand. Beta-blockers and calcium channel blockers are thought to delay the scarring process because they slow the heart rate and lessen the strength of the contraction of the heart - again, by analogy, the heart squeezes less often and with less force, allowing the blood to better reach the heart tissue and thereby damage leading to scar tissue.

So, for pediatric patients, the cardiologists often want to get the kids on beta-blockers at an early age. The earlier they start, the more they can delay the scarring process. The drugs don't actually fix the cellular-level cause of the disease, but they can delay the development of scar tissue and arrhythmias, and hopefully delay the development of symptoms at a later date.

For these reasons, the pediatric cardiologists that we've seen have been unconcerned about the lack of studies providing hard data about the effects of beta-blockers on populations of HCM patients. They know how the drugs work in individual patients, and that has been sufficient for them to prescribe them for many years.

Cynaburst
07-13-2007, 04:17 PM
Macbeth - Thank you for that well thought out and reasoned response.

mantrashak
07-13-2007, 07:26 PM
It's also worth noting that while many people can take beta blockers long term with few side effects, beta blockers can cause problems for others. It was these possible side effects that made me think twice at the age of 19.

The most common side effects are cold hands and feet & tiredness and sleep disturbance (nightmares).

Less common side effects include impotence, dizziness, wheezing, digestive tract problems, skin rashes and dry eyes.

Brownie
07-13-2007, 08:42 PM
Hi everyone,

I found the full text of the article in abstract above. I haven't worked my way through it entirely yet, but I will mention that the Noonan's cases were considered independently, but since their outcomes were not different than primary HCM cases they were included in the dataset.

Ultimately, we each have to make the treatment decisions that we are comfortable with, based on our individual cases and our physicians' advice, but it's always good to have a scientific footing for our decisions.

As the article is rather lengthy, I'll just give you the link.

http://content.onlinejacc.org/cgi/content/full/34/6/1813

Take care,

Abby

Sarah
07-13-2007, 10:02 PM
I can only speak to my own experience, but here it is for what it's worth.

I was diagnosed at 13 and put on Tenormin (atenolol, a beta-blocker) at 14 without having much in the way of symptoms. I did not tolerate Tenormin well and have subsequently taken propanolol, nadolol, metoprolol, sotolol, and probably one other beta blocker I'm forgetting. I'm 38 now.

The worst side effects for me have been the depression, nightmares, short-term memory loss and inability to concentrate. And my hair loss. They often try to give me anti-depressants, but I refuse. I've had almost every side effect listed for bb's. But some of the medications were better than others...I'm on metoprolol (Toprol) now and I don't have the insane nightmares/dreams that I had on propanolol or atenolol.

Despite long-term beta-blocker therapy, I've had afib for 5 years, and because of the afib I've had a mini stroke in 2000 and the coumadin for stroke prevention caused me to hemorrhage in 2005 (in my brain). Every doctor I've talked to has been politely surprised that I'm still fully functional.

The beta-blocker intolerance also let to a cascade of stronger and stronger medications that were (in retrospect) way over the top for what I needed then. So you need to cautious about the slippery slope effect.

And the bottom line is that no one REALLY knows. My brother met a former cardiologist who quit the profession because (in his own words) could not stand to give people medication when he couldn't know if it would help or hurt them. Beta blockers can make you worse. Calcium channel blockers almost killed me. Ditto dofetilide. Norpace has "sudden death" as one of the side effects.

The side effects of metroprolol that are also symptoms of HCM:
*uneven heartbeats;
*feeling light-headed, fainting;
*feeling short of breath, even with mild exertion;
*swelling of your ankles or feet;
*tired feeling

So why am I still on the beta-blocker? Because I am NOW symptomatic and it is the only thing (barring an AV node ablation with pacemaker) that controls my heart rate. Because of the afib, my resting heart rate runs around 100 plus, which is unstable and unpleasant to say the least. If I weren't in afib, I would have quit the beta blockers. It also reduces the palpitations a little bit--it is NOT controlling the afib itself, but it makes it more tolerable.

NOTE: It is very dangerous to stop taking a beta blocker suddenly and this is a major concern with kids/teens in that you have to make sure that they are taking their medication. I was VERY bad about taking my atenolol in high school and didn't understand why I was so sick.

The argument that long term beta blockers may prevent the hypertrophy from getting really bad may be true---my septal measurement is only 14 mm. BUT--that hasn't prevented me from having my own problems. About 20% of HCM patients get afib, so you may want to play the odds.

I believe it comes down to carefully considering your child, your family history, a little gut feeling and a roll of the dice. If you go with beta-blockers now, I would watch for side effects very very carefully and proceed with caution.

I'm truly sorry I don't think that there is a hard and fast answer here. You should call the HCMA office to see about more research studies--Lisa would have everything there is on this.

Best wishes,

Sarah

ben's mom
07-14-2007, 12:12 PM
Thank you Sarah for your detailed response (and everyone else who has replied). I appreciate your personal stories. They are very helpful.
Sara

Sarah
07-16-2007, 09:38 AM
You are very welcome. Feel free to PM me if you have any questions.

S

Seabee Vet
07-16-2007, 12:53 PM
I was first diagnosed with a "murmur" at 48. At 54, after an Echo, it was rediagnosed as HCM. I was given atenolol and immediately started have shortness of breath, I weaned myself off after about 6 months and the shortness of breath subsided. In 2003, at 59, the VA put me on verapimil, after I explained the atenolol, I was told I am intolerent of beta-blockers. I gradually started the shortness of breath again, but not as bad. In 2006, I was given the atenolol again...with the verapimil, this caused me to become light-headed and ocassionally pass out. The VA ER stopped the atenolol.

Last January, I was given 2 verapimil immediately after my myectomy and my heart stopped. Today, I take metoprolol tartrate (100mg) twice a day. I am taking NO other medication for my heart. I am 62 (and 1/2). The VA said the ONLY reason I was able to servive the Myectomy is beacuse I have been a weight lifter for the past 15 years and my strength help me through, I would not have been given the surgery otherwise.

Children and young people are better able to survive this, but I wanted to explain my situation concerning beta blockers and my age.

I hope this helps some of you.