The presence of angiographic collaterals in non-ST elevation myocardial infarction is a predictor of long-term clinical outcomes.

OBJECTIVES: To determine whether the presence of angiographic coronary collaterals is a predictor of long-term clinical outcomes in patients with non-ST elevation myocardial infarction (NSTEMI). BACKGROUND: The presence of coronary collaterals on angiography provides prognostic information in patients with STEMI, but it is unknown whether they provide prognostic information in patients with NSTEMI. METHODS: This was a prospective cohort study of 931 consecutive patients undergoing coronary angiography of which 269 (29%) had a NSTEMI. Baseline characteristics, angiographic details, and long-term clinical outcomes including death, recurrent MI, coronary artery bypass graft surgery (CABG), percutaneous coronary intervention (PCI), stroke, and congestive heart failure (CHF) were collected. Each clinical outcome as well as the combined endpoint of death, recurrent MI, CABG, PCI stroke and CHF was compared in subjects with and without collaterals. RESULTS: At one year, individuals with collaterals had significantly increased rates of the combined endpoint compared with those without (25% vs. 16%, P = 0.0001). On multivariate analysis, the presence of collaterals was a strong predictor of the combined endpoint of death, recurrent MI, CABG, PCI, stroke and CHF (HR 1.95, CI 95% 1.08-3.52; P = 0.027). Similarly, in the subset of 115 patients (43%) in whom the culprit artery was identified, the presence of collaterals was a strong negative predictor (HR 3.71, CI 1.31-10.57, P = 0.014), driven by a 13-fold increase in subsequent CABG. CONCLUSIONS: In patients with NSTEMI the presence of angiographic coronary collaterals is a predictor of long-term clinical outcomes primarily driven by increased rates of surgical revascularization.

The association of angiographic collaterals with long-term clinical outcomes in patients with chronic stable angina.

OBJECTIVES: To determine the impact of coronary collaterals in stable angina. BACKGROUND: Whether spontaneously visible coronary collaterals are associated with long-term clinical outcomes in stable angina remains unclear. METHODS: We prospectively enrolled patients with stable angina referred for coronary angiography and followed them clinically for 1 year. RESULTS: A total of 1,134 consecutive patients were enrolled, and of these, 550 had at least single-vessel coronary artery disease (CAD) and were included. Patients with collaterals had more congestive heart failure (16% vs. 9%, P = 0.023), peripheral vascular disease (22% vs. 15%, P = 0.044), and 2-vessel (36% vs. 26%) and 3-vessel (28% vs. 10%) CAD compared to those without collaterals (P < 0.001). Patients with collaterals were less likely to undergo percutaneous intervention at the time of the index angiogram (32% vs. 61%, P < 0.001). At 1 year, there were no differences in angina (HR 0.74, 95% CI 0.50-1.10; P = 0.141), myocardial infarction (MI) (HR 1.22, 95% CI 0.46-3.21; P = 0.691), revascularization (HR 0.84, 95% CI 0.55-1.30; P = 0.431), death (HR 1.83, 95% CI 0.63-5.31; P = 0.269), or the combined end-point of death, MI, and revascularization (HR 0.87, 95% CI 0.61-1.24; P = 0.426) between patients with and without collaterals. When analyzed according to collateral grade, patients with Rentrop grade 1 had less angina (HR 0.48, 95% CI 0.26-0.89; P = 0.019). CONCLUSIONS: At 1 year, there was no difference in adverse events between patients with or without collaterals. The presence of Rentrop grade 1 collaterals, however, was associated with significantly less angina.

CXCL5 gene polymorphisms and coronary collateralization.

Background: The presence of coronary collateralization is heterogenous, even amongst those with similar degrees of epicardial coronary artery stenoses. We hypothesized that genetic variation of CXCL5, a chemokine that mediates angiogenesis, is associated with coronary collateralization. Methods: We genotyped subjects undergoing coronary angiography for single nucleotide polymorphisms of CXCL5 and determined the presence of spontaneously visible coronary collaterals. Results: Subjects with collaterals had less angina (46 % vs 59 %, p = 0.006), and prior percutaneous coronary intervention (34 % vs 47 %, p = 0.010), and more hyperlipidemia (90 % vs 82 %, p = 0.018), peripheral arterial disease (25 % vs 17 %, p = 0.041), congestive heart failure (16 % vs 8 %, p = 0.007), and multi-vessel coronary artery disease (41 % vs 24 %, p = 0.0001) compared to those without collaterals. Multi-vessel disease and hyperlipidemia were positive predictors of angiographically visible collaterals while being a carrier of the CXCL5 polymorphism was a negative predictor. Conclusions: Coronary collateralization may, at least in part, be genetically determined.

Coronary angiography is a better predictor of mortality than noninvasive testing in patients evaluated for renal transplantation.

OBJECTIVES: The goal of this study was to compare whether coronary angiography or noninvasive imaging more accurately identifies coronary artery disease (CAD) and predicts mortality in patients with end-stage renal disease (ESRD) under evaluation for transplantation. BACKGROUND: CAD is a leading cause of mortality in patients with ESRD. The optimal method for identifying CAD in ESRD patients evaluated for transplantation remains controversial with a paucity of prognostic data currently available comparing noninvasive methods to coronary angiography. METHODS: The study cohort consisted of 57 patients undergoing both coronary angiography and stress perfusion imaging. Severe CAD was defined by angiography as ≥ 70% stenosis, and by noninvasive testing as ischemia in ≥ 1 zone. Follow-up for all cause mortality was 3.3 years. RESULTS: On noninvasive imaging, 63% had ischemia. On angiography, 40% had at least one vessel with severe stenoses. Abnormal perfusion was observed in 56% of patients without severe disease angiographically. Noninvasive imaging had poor specificity (24%) and poor positive predictive value (43%) for identifying severe disease. Angiography but not noninvasive imaging predicted survival; 3 year survival was 50% and 73% for patients with and without severe CAD by angiography (p<0.05). CONCLUSIONS: False positive scintigrams limited noninvasive imaging in patients with ESRD. Angiography was a better predictor of mortality compared with noninvasive testing.

Comparison between angiography and fractional flow reserve versus single-photon emission computed tomographic myocardial perfusion imaging for determining lesion significance in patients with multivessel coronary disease.

We hypothesized that myocardial perfusion imaging (MPI) would fail to identify all vascular zones with the potential for myocardial ischemia in patients with multivessel coronary disease (MVD). MPI is based on the concept of relative flow reserve. The ability of these techniques to determine the significance of a particular stenosis in the setting of MVD is questionable. Fractional flow reserve (FFR) can determine the significance of individual stenoses. Thirty-six patients with disease involving 88 arteries underwent angiography, FFR, and MPI. FFR was performed using a pressure wire with hyperemia from intracoronary adenosine. Myocardial perfusion images were analyzed quantitatively and segments assigned to a specific coronary artery. The relation between FFR and perfusion was determined for each vascular zone. Of the 88 vessels, the artery was occluded (n=20) or had an abnormal FFR

Plasma chemokine levels are associated with the presence and extent of angiographic coronary collaterals in chronic ischemic heart disease.

BACKGROUND: In patients with chronic ischemic heart disease (IHD), the presence and extent of spontaneously visible coronary collaterals are powerful determinants of clinical outcome. There is marked heterogeneity in the recruitment of coronary collaterals amongst patients with similar degrees of coronary artery stenoses, but the biological basis of this heterogeneity is not known. Chemokines are potent mediators of vascular remodeling in diverse biological settings. Their role in coronary collateralization has not been investigated. We sought to determine whether plasma levels of angiogenic and angiostatic chemokines are associated with of the presence and extent of coronary collaterals in patients with chronic IHD. METHODOLOGY/PRINCIPAL FINDINGS: We measured plasma concentrations of angiogenic and angiostatic chemokine ligands in 156 consecutive subjects undergoing coronary angiography with at least one ≥90% coronary stenosis and determined the presence and extent of spontaneously visible coronary collaterals using the Rentrop scoring system. Eighty-eight subjects (56%) had evidence of coronary collaterals. In a multivariable regression model, the concentration of the angiogenic ligands CXCL5, CXCL8 and CXCL12, hyperlipidemia, and an occluded artery were associated with the presence of collaterals; conversely, the concentration of the angiostatic ligand CXCL11, interferon-γ, hypertension and diabetes were associated with the absence of collaterals (ROC area 0.91). When analyzed according to extent of collateralization, higher Rentrop scores were significantly associated with increased concentration of the angiogenic ligand CXCL1 (p<0.0001), and decreased concentrations of angiostatic ligands CXCL9 (p<0.0001), CXCL10 (p = 0.002), and CXCL11 (p = 0.0002), and interferon-γ (p = 0.0004). CONCLUSIONS/SIGNIFICANCE: Plasma chemokine concentrations are associated with the presence and extent of spontaneously visible coronary artery collaterals and may be mechanistically involved in their recruitment.

Prevalence of unfavorable angiographic characteristics for percutaneous intervention in patients with unprotected left main coronary artery disease.

OBJECTIVES: The goal of this study was to determine the proportion of patients with left main coronary disease (LMCD) with unfavorable characteristics for percutaneous coronary intervention (PCI). BACKGROUND: Published series suggest that LMCD can be treated percutaneously, however, the proportion of patients in whom PCI is an option based on angiographic criteria is unknown. METHODS: In 13,228 consecutive coronary angiograms, 476 (3.6%) patients had < or =60% stenosis of the left main. In 232 patients with unprotected LMCD, the clinical characteristics and angiograms were reviewed with six features chosen as "unfavorable" for PCI: (1) Bifurcation LMCD, (2) occlusion of a major coronary, (3) ejection fraction <30%, (4) occlusion of a dominant RCA, (5) left dominant circulation, and (6) coexisting three-vessel disease. Treatment modality and 1 year mortality were determined. RESULTS: The mean age was 69 years and 68% were male. Unfavorable characteristics were common with at least one unfavorable characteristic seen in 80%. Bifurcation disease was the most common unfavorable characteristic observed (53%) and coexisting three-vessel disease was seen in 38%. Treatment consisted of CABG in 205 (88%), medical therapy in 24 (10%) and PCI in 3 (1%). Among patients referred for CABG, 1 year survival was 88% with similar rates of survival for those with favorable characteristics (86%) compared to those with at least one unfavorable characteristic (88%). CONCLUSIONS: Most patients with LMCD have at least one unfavorable characteristic for PCI suggesting that PCI may be a technically difficult option for most patients with LMCD.