Myocardial ischaemia in patients with primary APS: a 13N-ammonia PET assessment

Evaluate the presence and severity of myocardial ischaemia in a population of asymptomatic patients with primary APS (PAPS) using (13)N-ammonia PET.

We studied 36 patients, 18 with a diagnosis of PAPS and 18 healthy volunteers. All patients underwent a two-phase (rest-stress) (13)N-ammonia PET. Myocardial perfusion images were acquired and then analysed by two experts in the field.

We found ischaemia in 7/18 asymptomatic PAPS patients (38.8%). The anterolateral wall was the most commonly affected cardiac territory [5/7 PAPS patients (71.4%)]. In a severity analysis, we found that five patients (71.4%) had mild ischaemia, one patient (14.2%) had moderate ischaemia and another one (14.2%) had severe defects. All the healthy volunteers studied showed normal myocardial perfusion images.

An important proportion of PAPS patients, even when asymptomatic, showed myocardial perfusion defects assessed with PET. Most of the ischaemic patients had mild defects and the anterolateral wall was the territory mainly affected.