High Levels of a Substance Found in Ventricular Myocardium May Lead to Atrial Fibrillation

I have blogged about atrial fibrillation before and now a study arrives, which sheds new light on perhaps a marker of who might develop atrial fibrillation in the future.  This study reviewed the data of 5,445 patients followed from 10 to 15 years.  The authors used a marker know as BNP.

BNP is a substance found in the ventricular myocardium and since the weight of the left ventricle is so much greater than the right ventricle, it is used as a marker of left ventricular failure.  When patients present to the hospital or office with signs of congestive heart failure, such as shortness of breath on exertion or fluid retention one can measure the level of BNP in their blood.  The higher the level of BNP the more likely the diagnosis of heart failure is.

This substance is also present in acute coronary syndrome, which is a prelude to myocardial infarctions and is also present in myocardial infarctions.  Physicians can measure it and get a sense of how important the attack is based on how high the BNP is.  In practice, BNP is measured as NT-proBNP.

Past studies have used the Framingham Heart Study, which I have blogged about in the past and would actually be the subject of a long book.  Elevated levels of BNP were found to be predictive but only 68 subjects were found.  This study, the Cardiovascular Health Study Circ 2009; 120:1768-1774 utilized 5,445 patients.  There were 1,126 cases of atrial fibrillation.  Among those with the highest levels of BNP, there was a fourfold increase in the risk of atrial fibrillation compared to the lowest levels.

This study found that BNP was the strongest predictor of atrial fibrillation in comparison to other historic variables such as age, sex, medication use, blood pressure, echocardiographic variables, diabetes and heart failure.

Having a marker that may predict atrial fibrillation would allow us to aggressively treat those patients in an attempt to alter the disease course.  I am sure that these studies are in progress or being planned given the expected explosion of these cases as the population continues to age.

Tags: atrial fibrillation, BNP, myocardial infarctions, ventricular myocardium

This entry was posted on Wednesday, December 16th, 2009 at 1:08 pm and is filed under Atrial Fibrillation, Heart Failure, Myocardial Infarction. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.