This is big news, perhaps the most important from ESC2015 thus far.
The CHADS-VASC score may be able to predict stroke and death in patients with heart failure but NO atrial fibrillation.
That's right -- no AF.
Here is a case:
You are seeing a 75-year-old female with a history of ischemic cardiomyopathy (EF=35%), HTN and diabetes. She is in sinus rhythm but her CHADS-VASC score, that is, if she had AF, would be 6.
Without a history of AF, you prescribe aspirin. I don’t know about you, but I worry about stroke and systemic thromboembolism in this sort of patient. You almost wish for a “little” AF so that you can prescribe an anticoagulant.
An intriguing observational study presented at ESC this morning suggests we need to think about anticoagulants as a stroke prevention strategy in heart failure patients, whether or not they have AF.
Investigators from Denmark and UK mined the massive data bank available from three Danish health registries to better understand stroke risk in patients with heart failure and no AF. After an analysis of more than 35.000 patients over ten years, the research team found:
1) Pts w heart failure had a high risk of ischemic stroke, thromboembolism, and death whether or not AF was present.
2) The CHADS-VASC score modestly predicted these hard outcomes
3) The CHADS-VASC score had an excellent negative predictive value –low risk patients had truly low risk of events.
4) Pts with HF without AF who had CHADS-VASC greater than or equal to 4 exhibited a graded increase in absolute risk of stroke, thromboembolism and death.
5) The absolute risk of any thromboembolic event was higher among patients without AF compared with those patients who had AF.
My colleague Sue Hughes from Medscape Neurology has stellar coverage
of this important study.
I believe these observations will lead to a fertile area of new research. The idea of using anticoagulants, rather than antiplatelet drugs, in HF patients without AF is intriguing because there are millions of patients with heart failure without AF.
There is a lot of talk about outcomes in heart failure. People question whether things like admissions and readmissions are useful outcome measures. No one questions stroke or thromboembolism. These are important things to prevent.
The companies that make NOAC drugs have to be looking hard at these data.
I’m also wondering about what this data says about stroke mechanisms. There is great overlap in the populations of patients with AF and HF. Stroke does not seem to cluster around AF episodes. If we think of stroke as a manifestation of systemic disease (low flow, platelet aggregation, etc) why wouldn’t we expect HF patients to have a higher risk, regardless of the presence of AF?
I’m thinking a lot about this study. I’ll write more about it later.