Long-term prognostic value of 13N ammonia myocardial perfusion PET 

In this study (1) a large group of 256 patients (150 with know CAD) were evaluated with ammonia-PET for the evaluation of perfusion and coronary flow reserve.  Patients were then followed for an average of 5.4 years.  The most important findings of this study are 1) CFR allows further risk stratification in patients with normal perfusion and 2) in patients with abnormal perfusion CFR remained predictive for cardiac events. 
This is one the few larger scale studies that assessed outcome for both perfusion and CFR assessed with PET.  In an additional editorial Beanlands et al (2) discuss further the strengths and limitations of this study and also some pathophysiological issued related to CFR measurements.

References 1. Herzog BA, Husmans L, Valenta I et al.  Long-term prognostic value of  13N-ammonia myocardial perfusion positron emission tomography.  JACC 2009;54:150-6.

2. Beanlands RS, Ziadi MC, Williams K. Quantification of myocardial flow reverse using positron emission tomography. JACC 2009;54:157-9.

The content of this article reflects the personal opinion of the author/s and is not necessarily the official position of the European Society of Cardiology.