Beneficial Effect of Recruitable Collaterals

Abstract

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. Methods and 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: equation 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 ≥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.

Wide Genetic Variation in the Native Pial Collateral Circulation is a Major Determinant of Variation in Severity of Stroke

“…Although obtained in murine brain, these results likely extend to the other tissues, as collateral densities in skeletal muscle and intestine agree qualitatively with density in the pial circulation (Chalothorn et al, 2007;. They also may extend to other species including humans (Meier et al, 2007). (3) Remodeling of collaterals in the brain is nearly an order of magnitude faster than in skeletal muscle-a difference that may serve to more rapidly reduce ischemia and cell death in the high-risk penumbral cortex.…”

“…Doubts about its contribution may extend from the small caliber and apparent variable presence of these vessels (Mohr et al, 2004) plus the absence of methods-other than recent gene targeting approaches (Clayton et al, 2008;, to experimentally vary their abundance in animal studies. Meier et al (2007) recently reported indirect evidence suggesting that a large variation exists among healthy humans in the density and/or diameter of native coronary collaterals, as well as the ability of these vessels to enlarge/remodel in patients with obstructive disease (a process termed 'arteriogenesis'; Heil et al, 2006;Hossmann and Buschmann, 2005). Likewise, Liebeskind (2005), Bang and coworkers (2008) and Christoforidis et al (2009) recently found, using dynamic angiography in patients suffering acute obstruction of the MCA, that retrograde perfusion of the MCA tree downstream from the occlusion, which is dependent on collateral extent, varies substantially among patients.…”

Percutaneous Coronary Intervention Versus Optimal Medical Therapy for Chronic Total Coronary Occlusion With Well‐Developed Collaterals

“…Also, well‐developed collateral flow contribute clinical benefits in reducing the incidence of cardiac deaths and cardiovascular events in chronic stable angina patients. Furthermore, it is associated with beneficial effect after acute ischemic status in reducing infarct size and preserving LV function compared with CTO patients with poor‐developed collateral flow12, 13 However, there is limited evidence regarding the impact of PCI in patients with CTO with abundant collateral circulation compared with the optimal medical therapy (OMT) alone. Thus, the purpose of this study is to identify the impact of PCI on long‐term clinical outcomes in patients with at least 1 CTO target vessel and well‐developed collateral flow compared with OMT alone strategy in the drug‐eluting‐stent era.…”

Effect of collaterals on deaths and re-infarctions in patients with coronary artery disease: a meta-analysis

“…If this is true, then the atherosclerotic risk factors should be more often present in patient with collaterals than in those without. This is, however, not supported by the rather symmetric pattern of patient characteristics in most studies as metaanalysed in the current study [1,6,9,10,13,[15][16][17][18][19]. To assess this issue in a wider perspective, meta-regression was performed.…”

“…Although the exact mechanisms underlying the protective effects of the presence of collaterals are unclear, several factors might play a role. The collateral circulation has demonstrated clinical benefit regarding smaller infarct size, preservation of cardiac function after acute (re-) infarctions, and reduction in post-infarct ventricular dilatation [14][15][16][17][18][19][20][21][22]. Following a total coronary occlusion, residual perfusion to the myocardium persists through native coronary collaterals that open when an intercoronary pressure gradient between the source and recipient vessel develops.…”