Determinants of Coronary Steal in Chronic Total Coronary Occlusions
Donor Artery, Collateral, and Microvascular Resistance
Gerald S. Werner, MD*,*,
Michael Fritzenwanger, MD*,
Dirk Prochnau, MD*,
Gero Schwarz, MD*,
Markus Ferrari, MD*,
Wilbert Aarnoudse, MD ,
Nico H.J. Pijls, MD PhD and
Hans R. Figulla, MD*
* Clinic for Internal Medicine I, Friedrich-Schiller-University Jena, Jena, Germany
Department of Cardiology, Catharina Hospital, Eindhoven, the Netherlands

View larger version (9K):
[in a new window]
|
Figure 1 Schematic presentation of the electric analog model of coronary and collateral circulation (left; adapted from reference 7), and of the experimental setup (right). Mean aortic pressure (PAo) is recorded via the guiding catheter. Pressure at the takeoff of the collateral in the donor artery (PD) is recorded before recanalization, as well as the coronary flow reserve (CFR)D in the donor artery. Collateral blood flow velocity (APVOccl) and pressure (POccl) are recorded distal to the occlusion before balloon dilatation, and CFRR in the recanalized artery at the end of the procedure. The resistance of the occlusion (ROccl) is infinitesimal, and resistance indexes are calculated to describe the donor (RD) and collateral resistance (RC), and the microvascular resistance distal to the occlusion (RP). PRA = mean right atrial pressure.
|
|

View larger version (17K):
[in a new window]
|
Figure 2 (A) Changes of collateral blood flow velocity distal to the occlusion during adenosine infusion. A decrease of >15% indicated coronary steal (group S, left), an increase >15% indicated a positive collateral flow reserve (group R, right). Patients with no response beyond ±15% are shown in the middle. (B) Distribution of the collateral flow reserve during adenosine infusion.
|
|

View larger version (12K):
[in a new window]
|
Figure 3 Distribution of fractional flow reserve (FFR) measured in the donor artery at collateral takeoff in patients with (group S) and without coronary steal (group R). The cutoff of 0.75 is indicated by the horizontal line, but a grey zone up to 0.80 is accepted to indicate a hemodynamically significant stenosis.
|
|

View larger version (24K):
[in a new window]
|
Figure 4 Changes of donor artery resistance (RD), collateral resistance (RC), collateral pathway resistance (RCP), and microvascular resistance (RP) during adenosine infusion in group S (A, black symbols) and in group R (B, open symbols). For statistical evaluation see Table 3.
|
|
|