Beneficial effect of recruitable collaterals: a 10-year follow-up study in patients with stable coronary artery disease undergoing quantitative collateral measurements.
BACKGROUND
The prognostic relevance of the collateral circulation is still controversial. The goal of this study was to assess the impact on survival of quantitatively obtained, recruitable coronary collateral flow in patients with stable coronary artery disease during 10 years of follow-up.


RESULTS
Eight-hundred forty-five individuals (age, 62+/-11 years), 106 patients without coronary artery disease and 739 patients with chronic stable coronary artery disease, underwent a total of 1053 quantitative, coronary pressure-derived collateral measurements between March 1996 and April 2006. All patients were prospectively included in a collateral flow index (CFI) database containing information on recruitable collateral flow parameters obtained during a 1-minute coronary balloon occlusion. CFI was calculated as follows: CFI = (P(occl) - CVP)/(P(ao) - CVP) where P(occl) is mean coronary occlusive pressure, P(ao) is mean aortic pressure, and CVP is central venous pressure. Patients were divided into groups with poorly developed (CFI < 0.25) or well-grown collateral vessels (CFI > or = 0.25). Follow-up information on the occurrence of all-cause mortality and major adverse cardiac events after study inclusion was collected. Cumulative 10-year survival rates in relation to all-cause deaths and cardiac deaths were 71% and 88%, respectively, in patients with low CFI and 89% and 97% in the group with high CFI (P=0.0395, P=0.0109). Through the use of Cox proportional hazards analysis, the following variables independently predicted elevated cardiac mortality: age, low CFI (as a continuous variable), and current smoking.


CONCLUSIONS
A well-functioning coronary collateral circulation saves lives in patients with chronic stable coronary artery disease. Depending on the exact amount of collateral flow recruitable during a brief coronary occlusion, long-term cardiac mortality is reduced to one fourth compared with the situation without collateral supply.
Department of Cardiology, University Hospital, CH-3010 Bern, Switzerland.
Pascal
P
Meier
Steffen
S
Gloekler
Rainer
R
Zbinden
Sarah
S
Beckh
Stefano F
SF
de Marchi
Stephan
S
Zbinden
Kerstin
K
Wustmann
Michael
M
Billinger
Rolf
R
Vogel
Stéphane
S
Cook
Peter
P
Wenaweser
Mario
M
Togni
Stephan
S
Windecker
Bernhard
B
Meier
Christian
C
Seiler
D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D003097:Collateral Circulation / Q000502:physiology*; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
D015415:Biomarkers