Clinical utility of regadenoson for assessing fractional flow reserve.
OBJECTIVE
The aim of this study was to evaluate the efficacy of regadenoson, in comparison with adenosine, for assessing fractional flow reserve (FFR) of intermediate coronary artery stenoses (CAS).


BACKGROUND
Fractional flow reserve is an established invasive method for assessing the physiological significance of CAS. Regadenoson, a selective A(2A) receptor agonist, is an approved hyperemic agent for pharmacological stress imaging, but its role for measuring FFR is unknown.


METHODS
This prospective, single-center study enrolled 25 consecutive patients with intermediate CAS discovered during elective angiography (25 lesions). In each patient, FFR of the CAS was measured first by IV adenosine (140 μg/kg/min), followed by IV regadenoson (400 μg bolus). The intrapatient FFR correlation between adenosine and regadenoson was evaluated.


RESULTS
The mean age was 63 ± 11 years, and mean left ventricular ejection fraction was 58 ± 11%. Most patients were male (52%) and had hypertension (84%) and dyslipidemia (84%), with 24% having diabetes mellitus and 20% chronic obstructive pulmonary disease. The CAS was visually estimated during angiography (mean 58 ± 9%) and most often found in the left anterior descending coronary artery (48%). A strong, linear correlation of FFR was noted with adenosine and regadenoson (r = 0.985, p < 0.001). A hemodynamically significant lesion (FFR ≤ 0.80) was present in 52% with no reclassification of significance between adenosine and regadenoson. No serious events occurred with administration of either drug.


CONCLUSIONS
Our results suggest that a single IV bolus of regadenoson is as effective as an intravenous infusion of adenosine for measuring FFR and, given its ease of use, should be considered for FFR measurement in the catheterization laboratory.
Heart and Vascular Institute, University of Pittsburgh Medical Center (UPMC), Pittsburgh, Pennsylvania 15213, USA.
Pradeep K
PK
Nair
Oscar C
OC
Marroquin
Suresh R
SR
Mulukutla
Sameer
S
Khandhar
Vijay
V
Gulati
John T
JT
Schindler
Joon S
JS
Lee
D058917:Adenosine A2 Receptor Antagonists / Q000494:pharmacology; D000368:Aged; D000369:Aged, 80 and over; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000187:drug effects*; D006439:Hemodynamics; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011687:Purines / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D013223:Statistics as Topic; D013318:Stroke Volume; D014664:Vasodilation / Q000187:drug effects; D016277:Ventricular Function, Left
D058917:Adenosine A2 Receptor Antagonists; D011687:Purines; D011720:Pyrazoles; C430916:regadenoson