OBJECTIVE: Does the presence of atrial fibrillation (AF) have a significant incremental progostic value relative to myocardial perfusion single-photon emission computed tomography (MPS) with respect to risk of cardiac death (CD)? METHODS: A total of 16,048 consecutive patients undergoing MPS were evaluated. Of those, 384 patients (2.4%) had AF. The Cox proportional hazards method was used to determine the incremental prognostic value of the presence or absense of AF for the prediction of cardiac death. RESULTS: Atrial fibrillation was a significant predictor of CD in patients with normal, mildly abnormal, and severely abnormal scans. Patients with AF were 2 to 4 times more likely to suffer CD than those without AF. By multivariable analysis, AF patients also had a worse survival after adjustment for age, diabetes, shortness of breath, use of vasodilator stress, rest heart rate, and the nuclear variables. AF added incremental value to clinical, perfusion, and function variables. CONCLUSION: The presence of AF
independently increases the risk of cardiac events over perfusion and function variables in patients undergoing MPS. Patients with AF have a high risk of CD, even when MPS is only mildly abnormal. Whether patients with AF and mildly abnormal MPS constitute a group more deserving of early referral to cardiac catheterization is a question warranting further study.

COMMENT: patients with atrial fibrillation are more likely to die from cardiac disease, regardless of myocardial perfusion, ventricular function, or common clinical markers. It is a significant factor when assigning risk.

J Am Coll Cardiol. 2004 Sep 1;44(5):1062-70.

Prognostic implications of atrial fibrillation in patients undergoing myocardial perfusion single-photon emission computed tomography.

Abidov A, Hachamovitch R, Rozanski A, Hayes SW, Santos MM, Sciammarella MG, Cohen I, Gerlach J, Friedman JD, Germano G, Berman DS.

Departments of Imaging (Division of Nuclear Medicine) and Medicine (Division of Cardiology), Cedars-Sinai Medical Center, Los Angeles, California 90048, USA.