Efficacy of coronary fractional flow reserve using contrast medium compared to adenosine.
BACKGROUND
Coronary fractional flow reserve (FFR) is recommended as the gold standard method in evaluating intermediate coronary stenoses. However, there are significant debates concerning the agents and the timing of the measurement.


OBJECTIVE
To compare the contrast medium induced Pd/Pa ratio (CMR) with the FFR.


METHODS
We enrolled 28 consecutive patients with 34 intermediate lesions who underwent coronary FFR measurement by intracoronary (i.c.) adenosine. After baseline Pd/Pa was calculated, a single contrast medium (Iomeron) injection of 6 ml (3 ml/s) was performed manually. Within 10 s after the contrast medium injection, the CMR was calculated. Bolus injection of i.c. adenosine was performed to induce maximal hyperemia (from 60 µg to 600 µg), and when it was ≤ 0.80, the intermediate lesion was considered as significant.


RESULTS
After bolus i.c. adenosine, 12 lesions of 34 (35.3%) were identified as significant. The CMR value was 0.86 ±0.06 (range: 0.71-0.97). There were no significant differences between FFR and CMR values (p = 0.108). A substantial positive correlation between adenosine and contrast values was detected (0.886 and p < 0.001). Good agreement in Bland-Altman analysis was revealed (mean bias was 0.027, 95% confidence interval 0.038-0.092). Receiver operating characteristics curve analysis showed 90.9% sensitivity and 91.7% specificity for a cut-off value of 0.85 for the CMR compared to FFR (≤ 0.80).


CONCLUSIONS
Our study showed that measuring the CMR is a feasible method compared to FFR. The CMR may be used in situations where adenosine cannot be administered.
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Selim
S
Topcu
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Ibrahim Halil
IH
Tanboğa
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Enbiya
E
Aksakal
Department of Cardiology, Kars State Hospital, Kars, Turkey.
Uğur
U
Aksu
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Oktay
O
Gulcu
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Oğuzhan
O
Birdal
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Arif
A
Arısoy
Department of Cardiology, Kosuyolu Kartal Heart Training and Research Hospital, Istanbul, Turkey.
Arzu
A
Kalaycı
Department of Cardiology, Yalova State Hospital, Yalova, Turkey.
Fatih Rifat
FR
Ulusoy
Department of Cardiology, Faculty of Medicine, Atatürk University, Erzurum, Turkey.
Serdar
S
Sevimli
adenosine; contrast medium; fractional flow reserve