Establishment of a clinically correlated human pericardial fluid bank: evaluation of intrapericardial diagnostic potential

Technologies for intrapericardial delivery of therapeutics and cells

The pericardium, which surrounds the heart, provides a unique enclosed volume and a site for the delivery of agents to the heart and coronary arteries. While strategies for targeting the delivery of therapeutics to the heart are lacking, various technologies and nanodelivery approaches are emerging as promising methods for site specific delivery to increase therapeutic myocardial retention, efficacy, and bioactivity, while decreasing undesired systemic effects. Here, we provide a literature review of various approaches for intrapericardial delivery of agents. Emphasis is given to sustained delivery approaches (pumps and catheters) and localized release (patches, drug eluting stents, and support devices and meshes). Further, minimally invasive access techniques, pericardial access devices, pericardial washout and fluid analysis, as well as therapeutic and cell delivery vehicles are presented. Finally, several promising new therapeutic targets to treat heart diseases are highlighted.

Impaired coronary collateral vessel development in patients with proliferative diabetic retinopathy

BACKGROUND

Diabetic patients have been reported to have impaired coronary collateral vessel growth, although they have excessive neovascularization in the retina.

HYPOTHESIS

This study was designed to compare coronary collateral circulation (CCC) in patients with proliferative diabetic retinopathy (PDR) with that in patients without DR.

METHODS

Ninety diabetic patients with chronic total occlusion in at least one major epicardial coronary artery were enrolled in the study. Groups 1 and 2 consisted of 48 patients without DR and 42 patients with PDR, respectively. Coronary collateral circulation (CCC) was analyzed according to the Rentrop system. Each group was also divided into two subgroups according to poor and good CCC. Serum vascular endothelial growth factor (VEGF) levels were measured using the enzyme-linked immunosorbent assay (ELISA) kit.

RESULTS

The mean Rentrop collateral score was higher in Group 1 than in Group 2 (2.39 +/- 1.07 vs. 1.76 +/- 0.76, respectively, p < 0.001). When the two groups were compared with respect to poor and good CCC, poor CCC was higher in patients with PDR (64 vs. 36%, respectively, p = 0.01). Serum VEGF levels were higher in patients with PDR than in those without DR (219 +/- 99 vs. 139 +/- 98 pg/ml, p < 0.001); however, patients with poor and good CCC had similar VEGF levels.

CONCLUSIONS

We have shown that patients with PDR have a lower coronary collateral score than patients without DR. Also, serum VEGF was significantly higher in patients with PDR than in those without DR. These findings have suggested that diabetes mellitus may have a different action on retinal and coronary circulation.

Reduced pericardial levels of endostatin correlate with collateral development in patients with ischemic heart disease

OBJECTIVES

We investigated whether pericardial levels of a pro-angiogenic factor (vascular endothelial growth factor, VEGF) or an anti-angiogenic factor (endostatin) related to the presence of coronary collateral circulation in patients with significant coronary artery disease (CAD).

BACKGROUND

Coronary collateralization favorably alters the prognosis of patients with occlusive CAD. The specific factors that mediate and maintain collateral formation in coronary vessel occlusion are yet to be identified.

METHODS

Coronary angiograms from 39 patients undergoing coronary artery bypass surgery were evaluated for the absence of collaterals (n = 20) or the presence of Rentrop classification grade 3 collaterals (n = 19). Pericardial fluid samples were obtained at the time of surgery and were assayed for the VEGF and endostatin by enzyme-linked immunosorbent assay comparing the two groups of patients.

RESULTS

Vascular endothelial growth factor levels were not significantly different between the groups (28.86 +/- 4.67 pg/ml vs. 24.39 +/- 3.08 pg/ml, p = 0.43). However, pericardial fluid endostatin levels were nearly 40% lower in patients with grade 3 collateralization compared with those lacking angiographic evidence of collaterals (15.17 +/- 1.87 ng/ml vs. 24.25 +/- 2.08 ng/ml, p < 0.0025).

CONCLUSIONS

Pericardial fluid levels of endostatin, but not VEGF, are associated with the presence or absence of collaterals in patients with CAD. These data suggest that the angiogenesis inhibitor endostatin levels may locally modulate coronary collateral formation.