Rapid decline of collateral circulation increases susceptibility to myocardial ischemia: the trade-off of successful percutaneous recanalization of chronic total occlusions.
OBJECTIVE
We evaluated the time-behavior of changes in collateral circulation after successful percutaneous coronary intervention (PCI) with drug-eluting stents (DES) in chronic (>1 month) total occlusions (CTO), and assessed their relationship with myocardial ischemia.


BACKGROUND
It has been hypothesized that the immediate reduction of collateral flow after PCI of CTO could expose the patients to a higher risk of future ischemic events in the case of vessel reocclusion.


METHODS
In 42 patients with CTO, two consecutive balloon inflations and final DES deployment were performed after positioning of a pressure guidewire. Minimal lumen diameter (MLD), diameter stenosis (DS), angiographic collateral grading (Rentrop score), myocardial (FFRmyo), coronary (FFRcor), and collateral fractional flow reserve (FFRcoll) were evaluated. Chest pain and the sum of ST-segment elevation (SigmaST) were analyzed to document the occurrence and extent of myocardial ischemia.


RESULTS
Percutaneous coronary intervention induced a progressive improvement of indexes of stenosis severity (MLD, DS, Thrombolysis in Myocardial Infarction flow, FFRmyo, and FFRcor) and a rapid reduction in collateral circulation (FFRcoll and Rentrop score). A progressive worsening of ischemia at each balloon inflation occurred, concomitant with the reduction of collateral circulation. At linear regression analysis, an inverse relationship of FFRcoll with SigmaST (R2 = 0.352, p < 0.001) and angina pain score (R(2) = 0.247, p < 0.001) was observed.


CONCLUSIONS
In CTO, collateral circulation, which provides most coronary flow at baseline, rapidly declines after successful stent implantation and the restoration of an antegrade flow. This rapid de-recruitment of collaterals is likely to put such patients at risk of future ischemic events.
Zimarino
Marco
M
Institute of Cardiology and Center of Excellence on Aging, G. d'Annunzio University, Chieti, Italy.
Ausiello
Arturo
A
Contegiacomo
Gaetano
G
Riccardi
Irene
I
Renda
Giulia
G
Di Iorio
Cesare
C
De Caterina
Raffaele
R
D000368:Aged; D000787:Angina Pectoris / Q000209:etiology*; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects; D003097:Collateral Circulation; D017023:Coronary Angiography; D003326:Coronary Circulation; D023903:Coronary Restenosis; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017239:Paclitaxel / Q000008:administration & dosage; D020123:Sirolimus / Q000008:administration & dosage; D015607:Stents
D017239:Paclitaxel; D020123:Sirolimus