Elevated BNP Levels -- What does it mean?

[Cynaburst]

Hey everyone,

I have a question. My BNP levels were off the charts a few weeks ago when I had them tested at my Dr.'s request. (At his lab, they call it NPA, but he assures me that its the same thing). My results were 1340 with normal being 100 or less.

I know that it is an indicator of heart failure, and I know that most HCMers have an elevated count. What I want to know is if anything can be inferred by my having really high numbers.

When I was tested, I wasn't feeling any worse or better than normal. My symptoms are mild (mostly) to moderate occasionally. I do have a high gradient and am obstructed, and have significant mitral valve regurgitation.

I am currently on a high dose of atenolol, and will be trying Norpace next week, but suddenly after treating me for two years and being anti-intervention (i.e. ablation or myectomy), my doctor thinks that these numbers foreshadow future complications, i.e. a-fib and heart failure, although I am having none of that now.

What do you all think? What does that number really mean?

Thanks in advance.

Cynthia

[mtlieb]

Cynthia,

I've had a few BNP tests now and have to tell you the numbers confuse the heck out of me as well. I can tell you that when i was in congestive heart failure last spring... confirmed with all the prerequisite fluids and symptoms and a nice stay at the hospital to boot... my BNP never got much over 100. So obviously the numbers don't always reflect what is trully going on.

On the other hand, there are those here on the board with numbers well into the range you are speaking of, who have had severe problems with CHF. Hopefully they will chime in here and relate their experiences as well.

Is your doctor suggesting a myectomy at this point? I know there are folks that think i waited too long to have mine, but there's only so many times i can say bugfark! to them so i've pretty much given up on that. It's just the way the chips fell and i was following the treatment plan my doctors worked out with me. I was told by my first specialist that i wasn't even a candidate for myectomy, but that center doesn't have much surgical experience so i can't really blame them. Once i was in CHF though the ball really got rolling and i was refered to Cleveland for the surgery. The results have been amazing (although you did catch me during a bit of a bad stretch here).

I do believe there is merit to having the surgery before you start having problems with CHF. Once you start having fluid troubles, you're pretty much in it for life to one degree or another, myectomy or not.

Feel free to PM or email me anytime if you want to talk further. I may even go offline for a spell if you want to chat on the phone... just for you my dear.

Take care,

Jim

[Lisa Inman]

high BNP levels in blood tests

Cynthia:

I didn't know I had this question too, until reading over my most recent test reports yesterday. Very high "B Type Natriuretic Peptide" test, 1480 pg/mL with <101 being "normal". I looked it up using Google this morning and found the following description on the Cleveland Clinic site at:

http://www.clevelandclinic.org/heart.../bnp.htm<br />
Copied from that page:

B-Type Natriuretic Peptide (BNP) blood test

BNP is a substance secreted from the ventricles or lower chambers of the heart in response to changes in pressure that occur when heart failure develops and worsens. The level of BNP in the blood increases when heart failure symptoms worsen, and decreases when the heart failure condition is stable. The BNP level in a person with heart failure - even someone whose condition is stable - is higher than in a person with normal heart function.

Preparation

To test the BNP level, a small amount of blood is taken and placed in a machine that detects the level of BNP in your blood. The test takes about 15 minutes. The BNP level helps to determine if you have heart failure, rather than another condition that may cause similar symptoms. In addition, BNP help the physician make decisions about hospitalizations, agressive treatments, and future prognosis.

Results

* BNP levels below 100 pg/mL indicate no heart failure
* BNP levels of 100-300 suggest heart failure is present
* BNP levels above 300 pg/mL indicate mild heart failure
* BNP levels above 600 pg/mL indicate moderate heart failure.
* BNP levels above 900 pg/mL indicate severe heart failure.

BNP Research

In a recent study reported in the January issue of the Journal of the American College of Cardiology*, BNP accurately detected heart failure 83% of the time and reduced clinical indecision from 43% to 11%.

The study evaluated 321 patients presenting to the emergency department with acute dyspnea (shortness of breath). Patients had the BNP blood test and were also examined by physicians. Physicians were blinded to BNP levels and asked to give their probability of the patient having CHF and their final diagnosis. In addition, two physicians reviewing the patients symptoms, baseline characteristics, and clinical history were also asked to provide their level of clinical certainty in giving or ruling out a diagnosis of CHF.

The study showed that the BNP blood test provided an accurate diagnosis 81.1% of the time (sensitivity of 90%, and specificity of 74% at a cutoff of >100 pg/mL). In contrast, clinical judgment alone, yielded an accurate diagnosis 74% of the time. The BNP test also reduced uncertainty regarding the diagnosis from 43% to 11%. Average BNP levels also correlated well with New York Heart Association functional class levels and was able to distinguish heart failure symptoms from those of pulmonary causes of shortness of breath.

The authors conclude that the BNP test is a quick, inexpensive test which enhances current diagnostic assessment tools, and enables doctors to make the correct diagnosis of heart failure. Future research is evaluating the use of BNP to determine prognosis and decisions regarding treatment.


Resources:

* How Heart Failure Is Diagnosed, Cleveland Clinic Health System
* Breathing Not Properly trial indicates BNP tests should be incorporated into ACC/AHA CHF guidelines, heartwire, March 19, 2002, http://www.theheart.org/*
* Morrison LK, Harrison A, Krishnaswamy P, et al. Utility of a rapid B-natriuretic peptide assay in differentiating congestive heart failure from lung disease in patients presenting with dyspnea. J Am Coll Cardiol 2002 Jan 16; 39(2):202-9.

*a new browser window will open with this link. The inclusion of links to other web sites does not imply any endorsement of the material on the web sites or any association with their operators

©Cleveland Clinic Foundation, reviewed 8/03

Hope it's useful, thanks for asking the question, it made me notice it on my report.

Lisa Inman

[Linda]

We're still learning what the BNP means in HCM. Typically, the BNP will be higher just because the heart muscle walls are more stiff and less compliant than the normal heart. As we learn more, we'll be able to determine the best use of the study for the typical HCM patient. At this point, we need to see numbers in the condition and study from there to develope a true picture. It won't have the same implications on the same number scale shown in the article posted above, but time will tell what it truly does mean. At this point, if your doctor has done the test, go back to him or her and ask what they plan to do with the results and what they mean to you.

If anyone has gotten different or additional explanations from their docs, I'm sure they will post. This is one of the puzzle pieces Lisa follows closely at the medical conferences. Linda

[mtlieb]

Hi Cynthia,

I was searching for this link in response to another post, but thought it would be handy to plop it down here as well. You may have already read about this study before, but it doesn't hurt to repost the info as it pertains to our conversation the other night.

http://forum.4hcm.org/viewtopic.php?t=1436

Take care,

Jim

[williamm]

I've got today my PRO BNP test and the result was 4204 pg/ml. I don´t know exactly how it correlates to BNP but normal ranges are the same (< 100pg/ml). I'm non obstructive, no CHF, and my septum is 2.7cm. Anyone who did this test before got so high value? I am very worried because I don't fell so bad as this number shows. My EF is over 60%.

Regards,

William.