Friday, May 09, 2008

Precipitating causes of heart failure exacerbation

The OPTIMIZE-HF data base provided us with a wealth of information on heart failure. A report from that data base which focused on precipitating causes of exacerbations was recently published in the Archives of Internal Medicine.

In heart failure one can think about underlying causes and precipitating causes. While a good deal of evidence supported the importance of the former, there was little, up until now, on the importance of the latter even though expert opinion (as well as my mentors going all the way back to med school and residency) held that we should think about both. This paper, by showing that a majority of heart failure episodes had an identifiable precipitant, adds credence to that teaching. Precipitating causes matter.

DB of Med Rants provided a nice summary of the findings. I’ll just make a few observations I found interesting:

Patients with no identifiable precipitating cause had a modestly lower mortality. That’s counter-intuitive. You’d think the folks who decompensated for “no reason” would be those with the least hemodynamic reserve who are approaching “end stage”.

The distribution of length of stay was not a bell curve. The median length of stay was 4 days whereas the mean was 6.4. That tells me there were some outliers with very long stays. It matches real world experience.

Finally, I was a bit surprised that pulmonary embolism was not on the list of precipitating causes. That may reflect how hard investigators looked for PE rather than its actual occurrence. Recall that in COPD exacerbation, when you look for PE you find it in 25%. I’d like to see a similar study in hear failure.

No comments: