Significance of BNP blood test 16 months post MI

[p1954]

59 y male
MI Sept 2012  (takasubo cardiomyopathy)
BMI of 24.  
Light exercise most days. (I walked 10 minutes on recent treadmill stress test)
95% vegetarian since MI

Here are recent 2D echo/Doppler results (with cardiologists impressions) and some blood results:
LVEF   45-50%.    last year was 45% +- using transthoracic echo  
Mild left systolic dysfunction (Compared to prior year it seems slightly improved)
Mean pulmonary artery pressure 30 mm (consistent with moderate PH)
Tricuspid Doppler shows elevated right heart pressure of 55 mm (considering patient age is markedly abnormal)
Mitral valve Doppler consistent with diastolic dysfunction, grade 2
Cardiologist says I have stiffening in parts of my left ventricle (hypokinesis) but no hypertrophy.  This is consistent with initial echo which showed mild hypokinesis in 5 LV segments.  
Mildly dilated left ventricular cavity and left atrium.

BNP of 16  pg/ml
LDL 70 / TC  126  / TG 108  
CRP 0.2  mg/L

most of last year BP has been OK but recently is going up and been high at times and was high at doctors so started on 50 mg losartan to bring it and the pulmonary artery pressure down.  

The mention of PH with diastolic dysfunction is worrying to me as it seems a negative trend even though LV systolic function, according to my cardiologist, "seems slightly improved."  

Carvedilol  6.25 mg 2x/d
Pravastan  10 mg/d
Effient   10 mg/d
Aspirin  81 mg/d
Losartan-Potassium 50 mg/d  recently started

My question relates to the BNP results.  
Does the recent BNP value of 16 pg/ml shed any light on my condition/outlook?  
Could BNP be skewed artificially lower by the drugs I am taking so that it might be misleading?

[Flycaster305]

Interesting question and interesting response.  

I do know that BNP results are a positive indicator for CHF, but the numbers don't always equate to patient's severity of CHF symptoms.  I think a BNP number of 100 is an indicator for heart failure, but for a number of years I worked out daily and lived pretty routinely with BNP numbers between 150 - 200.  My blood is tested about every 90 days.  However, last year my heart bypasses failed and my BNP registered as high as 3150, and I didn't need a BNP test to know I had CHF as I would gain as much as 12 pounds overnight and couldn't lay down to sleep without about drowning.  I learned my BNP results today at the doctor's office, it was 365 and my lungs were clear.  My doctor told me today he has patients with BNP levels as high as 500 who get along pretty well and others with BNP of 100 who can hardly function, so I wonder if BNP levels are simply an indication, not a diagnosis of longevity.  

[CCFCardio MD2]

Your BNP is low/normal, suggesting your heart is not overloaded with fluid and the intracardiac pressures are not too high.  Your medications may relieve some of the pressure in your heart causing the BNP to be within normal limits, but they will not falsely lower it.