AF was independently associated with impaired hyperemic myocardial blood flow in patients with suspected obstructive CAD, and this association should be considered when interpreting myocardial perfusion imaging in patients with AF.
Global hyperemic myocardial blood flow (MBF) was lower in AF patients than in propensity score-matched sinus rhythm (SR) patients.
Impaired hyperemic MBF was more frequent in AF patients than in SR patients.
AF was independently associated with reduced hyperemic MBF in multivariate models.
The association between AF and reduced MBF holds in patients with similar CAD burden and risk profile, so it should be considered when interpreting perfusion imaging in AF patients.
This study looked at whether atrial fibrillation (AF), a common irregular heart rhythm, is linked to poorer blood flow to the heart muscle in people suspected of having blocked heart arteries. The researchers examined 31 patients with AF and compared them with 120 patients in normal rhythm who were matched for age, sex, body mass index, risk factors, calcium score, and the severity of findings on CT scans of the coronary arteries. All had a PET scan that measures blood flow in the heart muscle. During stress (maximal blood flow), patients with AF had markedly lower blood flow than matched patients in normal rhythm (median 1.9 vs. 3.0 mL/g/min). About 81% of AF patients had impaired blood flow in at least one heart segment, compared with 42% of those in normal rhythm. The difference remained after statistical adjustment in several models, suggesting AF is linked to reduced blood flow independent of the severity of coronary artery disease seen on CT. This research suggests that reduced blood flow on perfusion scans in people with AF may not always reflect blocked arteries alone, so doctors may need to take AF into account when interpreting these scans. The study was small and observational, and shows association rather than proving that AF causes the reduced blood flow.
Vartiainen N, Hartikainen S, Rissanen A, Kariniemi E, Leikas A, Strengell E, et al.. (2026). Atrial fibrillation is independently associated with impaired myocardial perfusion.. PloS one. https://doi.org/10.1371/journal.pone.0361402