Practice patterns, feasibility and efficacy of coronary artery angiography using distal radial approach

Background

Most patients undergo coronary angiography by transradial approach. However, recently distal radial approach has been introduced as a novel approach for coronary angiography and intervention. There is uncertainty on the feasibility and safety of distal radial approach for coronary angiography.

Methods

All consecutive 1450 coronary angiography cases (distal radial approach 237 cases, conventional transradial approach 1213 cases) between October 2018 and December 2019 were included in this study. Emergency coronary angiography cases and ad hoc coronary intervention cases were excluded. Patients were stratified into distal radial approach and conventional radial approach subgroups. Baseline characteristics, contrast amount, procedure time, radiation amount, fluoroscopy time, and complications in catheterization laboratory were statistically analyzed.

Results

There were no significant differences in age and gender between distal radial vs transradial groups: mean age, 70.8±10.5 vs 70.8±11.0 years; % of males, 77.2% vs 66.9%. Procedure time was significantly shorter in distal radial approach group (28.7±13.3 min vs 32.3±14.2 min, p<0.05) and total radiation amount during procedure was significantly less in distal radial approach group (366.4±189.5 ml vs 412.9±220.3 mGy, p<0.05).

Conclusions

Coronary angiography with distal radial approach decreases the procedure time and total radiation amount. It is feasible and safe in most stable patients.

Funding Acknowledgement

Type of funding source: None

Combination of a brief irrigation with tissue factor pathway inhibitor (TFPI) and adenovirus-mediated local TFPI gene transfer additively reduces neointima formation in balloon-injured rabbit carotid arteries

BACKGROUND

Tissue factor pathway inhibitor (TFPI) is a physiological antagonist of TF. We tested whether a brief irrigation with TFPI protein (rTFPI) or TFPI gene transfer into injured arteries would suppress TF activity and reduce fibroproliferative changes and investigated whether a combination of these methods would show an additive effect.

METHODS AND RESULTS

We prepared adenoviruses expressing either TFPI (AdTFPI) or bacterial ss-galactosidase (AdLacZ). Rabbit carotid arteries were balloon-injured and either infected with AdTFPI (or AdLacZ) or irrigated briefly with rTFPI (or saline). After injury, TF activity in arteries increased and was sustained; however, it was suppressed during the initial 24 hours by rTFPI irrigation (but not by gene transfer) and for a substantial period of time by TFPI gene transfer (but not by rTFPI irrigation). Four weeks later, the ratio of the intimal to medial areas was 34.3+/-8.7% (mean+/-SD, n=14) in saline-treated arteries and 33.3+/-4.2% in AdLacZ-infected arteries (P:=NS versus saline). However, it was reduced to 25.5+/-8.5% in rTFPI-irrigated arteries (P:<0.01 versus saline) and to 20.7+/-5.3% in AdTFPI-infected arteries (P:<0.01 versus AdLacZ). With a combination of irrigation and gene transfer, the ratio was further reduced to 12.6+/-4.7% (P:<0.01 versus rTFPI, P:<0.05 versus AdTFPI). Systemic coagulation status was not affected in these animals.

CONCLUSIONS

A combination of rTFPI irrigation and TFPI gene transfer overcomes the shortcomings shown by each method when used alone and achieves a full coverage of TF activity suppression, thereby enhancing their therapeutic effects without systemic side effects. This combination may be an effective strategy for the prevention of thrombosis and proliferative changes after angioplasty in humans.

Separate roles for H-Ras and Rac in signaling by transforming growth factor (TGF)-beta. H-Ras is essential for activation of MAP kinase, partially required for transcriptional activation by TGF-beta, but not required for signaling of growth suppression by TGF-beta

The signaling components located downstream of the transforming growth factor (TGF)-beta receptor are poorly understood. We constructed adenoviral vectors expressing a dominant-negative form of either H-Ras (AdCARasY57) or Rac (AdCARacN17), and used them to examine the roles of H-Ras and Rac in TGF-beta signaling using arterial endothelial cells in primary culture, and several established cells including a mink lung epithelial cell line (Mv1Lu). The rapid activation of p42/44 MAP kinase (MAPK) by TGF-beta1 was eliminated completely, and transcriptional activation by TGF-beta1 of the plasminogen activator inhibitor-1 gene was reduced by 50% in both endothelial cells and Mv1Lu when they were infected with AdCARasY57. However, the antiproliferative effect of TGF-beta, as assessed by the induction of the mRNA for Cdk4/6-specific inhibitor p15INK4B and by DNA synthesis, was not affected in AdCARasY57-infected cells. A MAPK kinase (MEK)1/2 inhibitor, U0126 also abolished MAPK activation and partially inhibited transcriptional activation by TGF-beta, suggesting that MAPK may be partially involved in this pathway. MAPK activation, transcriptional activation and growth suppression by TGF-beta were all unaffected in cells infected with AdCARacN17, although the DNA synthesis elicited by serum mitogens was suppressed completely in the infected cells. Our data indicate that H-Ras is essential for mitogen-activated protein kinase activation, partly required for transcriptional activation by TGF-beta, but not critically involved in the signaling that exerts the antiproliferative effect of TGF-beta. The results also suggest that Rac may not serve as an essential molecule in signaling by TGF-beta in the cells tested.

Adenovirus-mediated local expression of human tissue factor pathway inhibitor eliminates shear stress-induced recurrent thrombosis in the injured carotid artery of the rabbit

The main cause of acute coronary syndrome may be recurrent thrombosis, which is initiated by the activation of the extrinsic coagulation pathway. Tissue factor (TF) pathway inhibitor (TFPI) efficiently inhibits an early step in this pathway by the formation of a complex with factor VIIa, TF, and factor Xa. We determined whether local TFPI gene transfer can inhibit thrombosis in an injured artery without inducing systemic side effects. Balloon-injured rabbit carotid arteries were infected with an adenoviral vector that expressed either human TFPI (AdCATFPI) or bacterial beta-galactosidase (AdCALacZ). Two to 6 days after gene transfer, thrombosis was induced by the production of constant stenosis of the artery, and blood flow was measured continuously with an electromagnetic flow probe. A cyclic flow variation, which is thought to reflect the recurrent formation and dislodgment of mural thrombi, was observed in all AdCALacZ-infected arteries as well as in saline-infused arteries. In contrast, no cyclic flow variation was detectable in AdCATFPI-transfected arteries, even in the presence of epinephrine (1 microg. kg-1. min-1 infusion). Prothrombin time, activated partial thromboplastin time, and the ex vivo platelet aggregation induced by either adenosine diphosphate or collagen were unaltered in AdCATFPI-infected rabbits. We found that in vivo TFPI gene transfer into an injured artery completely inhibits the recurrent thrombosis induced by shear stress even in the presence of catecholamine, without affecting systemic coagulation status. Adenovirus-mediated local expression of TFPI may have the potential for the treatment of human thrombosis.

Blockade of type beta transforming growth factor signaling prevents liver fibrosis and dysfunction in the rat

We eliminated type beta transforming growth factor (TGF-beta) signaling by adenovirus-mediated local expression of a dominant-negative type II TGF-beta receptor (AdCATbeta-TR) in the liver of rats treated with dimethylnitrosamine, a model of persistent liver fibrosis. In rats that received a single application of AdCATbeta-TR via the portal vein, liver fibrosis as assessed by histology and hydroxyproline content was markedly attenuated. All AdCATbeta-TR-treated rats remained alive, and their serum levels of hyaluronic acid and transaminases remained at low levels, whereas all the AdCATbeta-TR-untreated rats died of liver dysfunction. The results demonstrate that TGF-beta does play a central role in liver fibrogenesis and indicate clearly in a persistent fibrosis model that prevention of fibrosis by anti-TGF-beta intervention could be therapeutically useful.