Values of Radial Artery Provocation Tests at Different Doses of Ergonovine in the Diagnosis of Coronary Artery Spasm.

The intracoronary drug provocation test has been the gold standard for diagnosis of coronary artery spasm (CAS); however, it has been identified with severe complications. In this study, we investigated the sensitivity, specificity, and safety of radial artery provocation test at different doses of ergonovine in the diagnosis of CAS. This study enrolled 57 patients, which were then divided into CAS group (n = 24) and control group (n = 33) after intracoronary ergonovine provocation test. All patients underwent radial artery provocation test at different doses of ergonovine. The predictive values of radial artery provocation test for the diagnosis of CAS were analyzed using receiver operator characteristic curve. In the radial artery provocation test at different doses of ergonovine, radial artery stenosis degree was all found to be significantly higher in the CAS group than in the control group (all P < 0.001). In the control group, significant differences were noted in the radial artery stenosis degree between different doses of ergonovine (all P < 0.05). In the CAS group, the radial artery stenosis degree was significantly higher in 160 µg and 100 µg of ergonovine than in 60 µg of ergonovine (all P < 0.001). The radial artery provocation test at 60 µg and 100 µg of ergonovine did not cause CAS, chest pain, and ECG ischemic changes. In the radial artery provocation test at 160 µg of ergonovine, some patients had CAS, chest pain, and ECG ischemic changes. The specificity and sensitivity of radial artery provocation test were 90.91% and 50.00% at 60 µg of ergonovine, 96.97% and 66.67% at 100 µg of ergonovine, and 90.91% and 95.83% at 160 µg of ergonovine for the diagnosis of CAS. As per our findings, we can conclude that the basic tension of radial artery increases in the CAS group. With the increase of ergonovine doses, its sensitivity and specificity improve, but its safety decreases. We will explore the most optimal dose of ergonovine in future studies.

Blood flow changes in the forearm arteries after ultrasound-guided costoclavicular brachial plexus blocks: a prospective observational study.

BACKGROUND: An increase in blood flow in the forearm arteries has been reported after brachial plexus block (BPB). However, few studies have quantitatively analysed the blood flow of the forearm arteries after BPB or have studied only partial haemodynamic parameters. The purpose of the present study was to comprehensively assess blood flow changes in the distal radial artery (RA) and ulnar artery (UA) after BPB performed via a new costoclavicular space (CCS) approach using colour Doppler ultrasound. METHODS: Thirty patients who underwent amputated finger replantation and received ultrasound-guided costoclavicular BPB were included in the study. The haemodynamic parameters of the RA and UA were recorded before the block and 10 min, 20 min, and 30 min after the block using colour Doppler ultrasound to determine the peak systolic velocity (PSV), end-diastolic velocity (EDV), mean velocity (Vmean), pulsatility index (PI), resistance index (RI) and area. The volumetric flow rate (VFR) was calculated using the formula Q = area×Vmean. The aforementioned parameters were compared not only before and after the BPB but also between the RA and UA. RESULTS: Compared with those of the respective baselines, there was a significant increase in the PSV, EDV, Vmean, area, and VFR and a significant decrease in the PI and RI of the RA and UA 10 min, 20 min, and 30 min post-block. The increase 30 min post-block in EDV (258.68 % in the RA, 279.63 % in the UA) was the most notable, followed by that in the Vmean (183.36 % in the RA, 235.24 % in the UA), and the PSV (139.11 % in the RA, 153.15 % in the UA) changed minimally. The Vmean and VFR of the RA were significantly greater than those of the UA before the BPB; however, there was no significant difference in the VFR between the RA and UA after the BPB. CONCLUSIONS: A costoclavicular BPB can increase blood flow in the forearm arteries. The RA had a higher volumetric flow rate than the UA before the BPB; however, the potential blood supply capacity of the UA was similar to that of the RA after a BPB. TRIAL REGISTRATION: This study was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/searchproj.aspx, clinical trial number: ChiCTR 1900023796, date of registration: June 12, 2019).

Diagnosis of coronary artery spasm by ergonovine provocation test of radial artery.

We investigated the sensitivity, specificity and safety of ergonovine provocation test of radial artery in the diagnosis of coronary artery spasm (CAS). The patients who came to our hospital for chest pain from January to June 2020 as well as had coronary stenosis < 50% and no radial artery stenosis, were enrolled in this study. These patients were divided into CAS group and control group after intracoronary ergonovine provocation test. All patients underwent ergonovine provocation test of radial artery, the inner diameter (D0 and D1) and the peak systolic velocities (PSV0 and PSV1) of the radial artery were measured by ultrasound before and after ergonovine provocation. The predictive value of ergonovine provocation test of radial artery for the diagnosis of CAS was analyzed using receiver operator characteristic (ROC) curve. There were 19 patients in the CAS group and 28 patients in the control group. Low density lipoprotein cholesterol and smoking rate were significantly higher in the CAS group than in the control group (all P < 0.05), but there were no significant differences in other items (P > 0.05) between the two groups. In the ergonovine provocation test of radial artery, degree of radial artery stenosis was significantly higher in the CAS group [41.50% (35.60%, 50.00%)] than in the control group [11.25% (5.15%, 23.00%)] (P = 0.000), but there were no siginificant differences in D0, PSV0 and PSV1 between the two groups (P > 0.05). The area under ROC curve of ergonovine (120 µg) provocation test of radial artery for the diagnosis of CAS was 0.912 with 95%CI: 0.792-0.975, P = 0.001, cut-off of 31%, specificity of 92.86% and sensitivity of 84.21%. The ergonovine (120 µg) provocation test of radial artery did not cause any adverse reactions. We concluded that the ergonovine provocation test of radial artery has high sensitivity, specificity and safety in the diagnosis of CAS.

Vascular effect of levonorgestrel intrauterine system on heavy menstrual bleeding: is it associated with hemodynamic changes in uterine, radial, and spiral arteries?

The aim of this study was to evaluate the clinical and blood flow changes associated with the use of a levonorgestrel-releasing intrauterine device (LNG-IUD) in patients with idiopathic heavy menstrual bleeding (HMB). LNG-IUD was inserted into a total of 91 patients (39.5 ± 5.4 years) who were diagnosed with HMB. Uterine volume, ovarian volume, uterine, radial and spiral artery blood flow, Pictorial Blood Loss Assessment Chart (PBAC) scores, and other clinical and laboratory parameters were evaluated before and 12 months after insertion of LNG-IUD. Compared to pre-insertion values, LNG-IUD dramatically improved haemoglobin, PBAC scores, and endometrial thickness. Mean resistance indices of radial and spiral arteries significantly increased 12 months after insertion. Our study results suggest that a significant increase in the resistance indices of the intra-myometrial arteries in LNG-IUD users one year after insertion may be due to its local progestational effects, indicating a possible mechanism of LNG-IUD in reducing menstrual blood flow.Impact StatementsWhat is already known on this subject? The mechanisms of action of LNG-IUD on heavy menstrual bleeding include atrophy, decidualization and vascular changes of in the endometrium, resulting endometrial suppression. However, the exact mechanism to stop bleeding is not clear.What do the results of this study add? The present study suggests that one of the effects of the LNG-IUD on heavy menstrual bleeding is its ability to increase the resistance indexes of the intra-myometrial arteries.What are the implications of these findings for clinical practice and/or further research? These results will foster further studies on the effects of LNG-IUD on intra-myometrial arteries and will further assure clinicians on the vascular effect of LNG-IUD during management of heavy menstrual bleeding which includes hysterectomy as a final step.

Functional effects of urotensin-II on intracellular pH regulators in human radial artery smooth muscle cells.

The regulation of intracellular pH (pHi) plays a vital role in various cellular functions. We previously demonstrated that three different acid extruders, the Na+-H+ exchanger (NHE), Na+-HCO3- co-transporter (NBC) and H+-linked monocarboxylate transporter (MCT), functioned together in cultured human radial artery smooth muscle cells (HRASMCs). However, the functions of acid-loading transporters in HRASMCs remain poorly understood. Urotensin II (U-II), one of the most potent vasoconstrictors, is highly expressed in many cardiovascular diseases. The aim of this present study was to determine the concentration effect of U-II (3 pM∼100 nM) on the functional activity of pHi regulators in HRASMCs. Cultured HRASMCs were derived from segments of human radial arteries obtained from patients undergoing bypass grafting. Changes in pHi recovery due to intracellular acidification and alkalization induced by NH4Cl prepulse and Na-acetate prepulse, respectively, were detected by microspectrofluorimetry with the pH-sensitive fluorescent dye BCECF. Our present study showed that (a) U-II increased the activity of NHE in a concentration-dependent manner but did not change that of NBC or MCT or resting pHi, (b) the Cl--OH- exchanger (CHE) facilitated base extrusion, and (c) U-II induced a concentration-dependent increase in the activity of CHE. In conclusion, for the first time, our results highlight a concentration-dependent increase in the activity of NHE and CHE, but not NBC and MCT, induced by U-II in HRASMCs.

Preventing spasm of the radial artery conduit during coronary artery bypass grafting: Nicardipine versus verapamil.

BACKGROUND AND AIM OF THE STUDY: In vitro studies have shown a reduction in radial artery spasm with the use of calcium antagonists. The purpose of this study was to evaluate the efficacy of topical treatment of the radial artery conduit using either verapamil or nicardipine before the anastomoses. METHODS: This prospective randomized study included 131 patients, who underwent coronary artery bypass grafting surgery with the use of the radial artery as a conduit. In 65 patients, the harvested radial artery was topically treated with verapamil and in 66 patients with nicardipine. After harvesting the radial artery, the direct flow through the conduit was measured in vitro before 5-minute incubation in nicardipine or verapamil and measured again after incubation. The flow before and after incubation was compared. Postincubation flow was also compared in the two groups. After performing the anastomosis, the flow through the radial artery was measured in vivo. RESULTS: The mean flow after NaCl incubation was 19.93 ± 12.66 mL/min and after incubation in the Ca+ channel blocker 47.16 ± 14.58 mL/min (P < .001). No significant difference in postincubation free flow was found between verapamil (46.29 ± 15.43 mL/min) and nicardipine (48.01 ± 13.77 mL/min; P = .503). CONCLUSION: Topical treatment with Ca+ channel blockers reduces radial artery spasm and significantly increases the free flow through the radial artery conduit. Nicardipine is a safe and effective alternative of verapamil in preventing spasm of radial artery conduit.

Effect of Calcium-Channel Blocker Therapy on Radial Artery Grafts After Coronary Bypass Surgery.

BACKGROUND: Few studies have evaluated the effect of chronic calcium-channel blocker therapy (CCB) on the angiographic and clinical outcome of radial artery (RA) grafts used for coronary bypass surgery. OBJECTIVES: The purpose of this study was to evaluate if CCB influences midterm clinical and angiographic outcomes of RA grafts. METHODS: Patient-level data of 6 angiographic randomized trials evaluating RA graft status at midterm follow-up were joined in this observational analysis. Cox regression and propensity score methods were used to evaluate the effect of CCB on the incidence of a composite of major adverse cardiac events (MACE) (death, myocardial infarction, and repeat revascularization) and graft occlusion. RESULTS: The study population included 732 patients (502 on CCB). The median clinical follow-up was 60 months. The cumulative incidence of MACE at 36, 72, and 108 months was 3.7% vs. 9.3%, 13.4% vs. 17.6%, and 16.8% vs. 20.5% in the CCB and no CCB groups, respectively (log-rank p = 0.003). Protocol-driven angiographic follow-up was available in 243 patients in the CCB group and 200 in the no CCB group. The median angiographic follow-up was 55 months. The cumulative incidence of RA occlusion at 36, 72, and 108 months was 0.9% vs. 8.6%, 9.6% vs. 21.4%, and 14.3% vs. 38.9% in the CCB and no CCB groups, respectively (log-rank p < 0.001). After controlling for known confounding, CCB therapy was found to be consistently associated with a significantly lower risk of MACE (multivariate Cox hazard ratio: 0.52; 95% confidence interval: 0.31 to 0.89; p = 0.02) and RA graft occlusion (multivariate Cox hazard ratio: 0.20; 95% confidence interval: 0.08 to 0.49; p < 0.001). CONCLUSIONS: In patients with RA grafts CCB is associated with significantly better midterm clinical and angiographic RA outcomes.

Republished: Transradial approach in the treatment of a sacral dural arteriovenous fistula: a technical note.

Sacral dural arteriovenous fistulas (SDAVFs) are rare, constituting no more than 10% of all spinal dural fistulas. They are most commonly fed by the lateral sacral artery (LSA), a branch of the internal iliac artery (IIA). Catheterization of this vessel requires either a crossover at the aortic bifurcation in cases of right femoral access or retrograde catheterization from the ipsilateral common femoral artery. We present the case of a 79-year-old man with tethered cord syndrome and a symptomatic SDAVF fed by two feeders from the left LSA. Spinal diagnostic angiography was made exceptionally challenging by an aorto-bi-iliac endograft, and selective catheterization of the left IIA was not possible. The patient could not undergo surgery due to multiple comorbidities, therefore embolization was considered the best approach. The procedure was carried out through a transradial access (TRA) with Onyx and n-butyl cyanoacrylate. The SDAVF was successfully treated and the patient made a full neurological recovery.

Altered bioavailability of epoxyeicosatrienoic acids is associated with conduit artery endothelial dysfunction in type 2 diabetic patients.

BACKGROUND: This pathophysiological study addressed the hypothesis that soluble epoxide hydrolase (sEH), which metabolizes the vasodilator and anti-inflammatory epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs), contributes to conduit artery endothelial dysfunction in type 2 diabetes. METHODS AND RESULTS: Radial artery endothelium-dependent flow-mediated dilatation in response to hand skin heating was reduced in essential hypertensive patients (n = 9) and type 2 diabetic subjects with (n = 19) or without hypertension (n = 10) compared to healthy subjects (n = 36), taking into consideration cardiovascular risk factors, flow stimulus and endothelium-independent dilatation to glyceryl trinitrate. Diabetic patients but not non-diabetic hypertensive subjects displayed elevated whole blood reactive oxygen species levels and loss of NO release during heating, assessed by measuring local plasma nitrite variation. Moreover, plasma levels of EET regioisomers increased during heating in healthy subjects, did not change in hypertensive patients and decreased in diabetic patients. Correlation analysis showed in the overall population that the less NO and EETs bioavailability increases during heating, the more flow-mediated dilatation is reduced. The expression and activity of sEH, measured in isolated peripheral blood mononuclear cells, was elevated in diabetic but not hypertensive patients, leading to increased EETs conversion to DHETs. Finally, hyperglycemic and hyperinsulinemic euglycemic clamps induced a decrease in flow-mediated dilatation in healthy subjects and this was associated with an altered EETs release during heating. CONCLUSIONS: These results demonstrate that an increased EETs degradation by sEH and altered NO bioavailability are associated with conduit artery endothelial dysfunction in type 2 diabetic patients independently from their hypertensive status. The hyperinsulinemic and hyperglycemic state in these patients may contribute to these alterations. Trial registration NCT02311075. Registered December 8, 2014.

Relaxation matters: comparison of in-vitro vasodilatory role of botulinum toxin-A and papaverine in human radial artery grafts.

BACKGROUND: Radial artery (RA) is widely used in coronary artery bypass (CABG) surgery and the prevention of spasm is crucial for graft patency. Botulinum toxin A (BTX-A) and B are commonly used for aesthetic reasons and neuromuscular disorders. They are proven to raise blood flow and increase survival of ischemic skin flaps. In this study we evaluated and compared the vasodilator effects of BTX-A and papaverine on human RA grafts. METHODS: After resting 60 min in isolated organ baths, human RA grafts were examined. Contraction responses for different doses of serotonin (5-HT) and endothelin-1 (ET-1) were evaluated as a percent of maximum contraction response elicited by 80 mM potassium chloride (KCl). The inhibitory effects of BTX-A and papaverine on contraction responses taken at the 0th hour were compared with the 1st and 2nd hour responses. Inhibitory effects of BTX-A and papaverine against the contractile agent were evaluated by comparing the results of the first and last (0th and 2nd hour) application. RESULTS: In low concentrations, when we compared the effects of BTX-A (10- 8 M) and papaverine (10- 6 M) on 5-HT, papaverine was found to be more effective at both the 0th and 2nd hour (p < 0.05). Both BTX-A and papaverine inhibited the maximum contractile effect of ET-1 to the same extent at the 0th hour; but, the inhibitory effect of BTX-A was significantly stronger at the 2nd hour (p < 0.05). In high concentrations, when we compared the effects of BTX-A (10- 6 M) and papaverine (10- 4 M) on 5-HT, papaverine showed stronger inhibition (p < 0.05), whereas both agents had similar action of inhibition on ET-1 mediated maximum contraction responses. CONCLUSION: BTX-A inhibits both ET-1 and 5-HT induced contractions and its effectiveness does not decrease over time as observed with papaverine. This study is the first in the literature using human RA for prevention of vasospasm by BTX-A.

Transradial interventions in contemporary vascular surgery practice.

OBJECTIVES: Upper extremity arterial access is often required for endovascular procedures, especially for antegrade access to the visceral aortic branches. Radial arterial access has been shown previously to have low complication rates, and patients tolerate the procedure well and are able to recover quickly. However, transradial access remains relatively uncommon amongst vascular surgeons. METHODS: The radial artery was evaluated by ultrasound to evaluate for adequate caliber, and to identify any aberrant anatomy or arterial loops. A modified Barbeau test was performed to ensure sufficient collateral circulation. A cocktail of nitroglycerin, verapamil and heparin was administered intra-arterially to combat vasospasm. Sheaths up to 6 French were utilized for interventions. On completion of the procedure, a compression band was used for hemostasis in all cases. RESULTS: Twenty-five interventions were performed in 24 patients. The left radial artery was used in 23/25 cases (92.0%). Procedures included visceral and renal artery interventions; stent graft repair of a renal artery aneurysm; embolization of splenic, pancreaticoduodenal and internal mammary aneurysms; embolization of bilateral hypogastric arteries following blunt pelvic trauma; interventions for peripheral arterial disease; delivery of a renal snorkel graft during endovascular aortic aneurysm repair, and access for diagnostic catheters during thoracic endovascular aortic aneurysm repair. Technical success was 92.0%. There was one post-operative radial artery occlusion (4.3%) which led to paresthesias but resolved with anticoagulation. There were no instances of arterial rupture, hematoma, or hand ischemia requiring intervention. CONCLUSIONS: Using the transradial approach, we have demonstrated a high technical success rate over a range of clinical contexts with minimal morbidity and no significant complications such as bleeding or hand ischemia. The safety profile compares favorably to historical complication rates from brachial access. Radial access is a safe and useful skill for vascular surgeons to master.

Safety of Calcium-Channel Blockers During Radial Cardiac Catheterization in Patients With Acute Myocardial Infarction or Systolic Heart Failure.

OBJECTIVES: The aim of this study was to evaluate the safety of calcium-channel blockers (CCBs) during radial artery catheterization in two populations with a contraindication to their use. BACKGROUND: Cardiac catheterization performed via the radial approach has become increasingly common worldwide, but adoption has been slow in the United States. One possible explanation is concern over radial artery vasospasm, which can complicate procedures. Spasmolytic drugs, typically intra-arterial CCBs, are used to prevent spasm, but their safety is not well established in high-risk populations, such as those with ST-segment elevation myocardial infarction (STEMI) or systolic heart failure (HF), in which CCB may be contraindicated. METHODS: Consecutive STEMI and HF patients undergoing cardiac catheterization over a 1-year period were prospectively evaluated. All operators in our laboratory use the radial approach unless contraindicated. All patients received CCB immediately after sheath insertion. The primary outcome of interest was change in blood pressure immediately after CCB. Procedural outcomes were also evaluated. RESULTS: A total of 184 patients were included in the study (54 with STEMI and 129 with HF). There was a significant drop in systolic blood pressure (SBP) and diastolic blood pressure (DBP) following verapamil administration (P<.001 for both), but no change in HR (P>.99). SBP decreased more than 20 mm Hg in 15.7% of patients, none of whom required initiation of vasopressors. In regression analysis, only baseline SBP correlated significantly with the change in blood pressure. CONCLUSIONS: Patients with STEMI or HF can safely tolerate intra-arterial CCB during radial catheterization.

Vasodilatory efficacy and impact of papaverine on endothelium in radial artery predilatation for cabg surgery: in search for optimal concentration

Abstract Objective: The aim of this study was to compare the efficacy of two different papaverine concentrations (0.5 mg/ml and 2 mg/ml) for vasospasm prevention and their impact on endothelium integrity. Methods: We have studied distal segments of radial arteries obtained by no-touch technique from coronary artery bypass graft (CABG) patients (n=10). The vasodilatory effect of papaverine (concentrations of 0.5 mg/ml and 2 mg/ml) was assessed in vitro, in isometric tension studies using ex vivo myography (organ bath technique) and arterial rings precontracted with potassium chloride (KCl) and phenylephrine. The impact of papaverine on endothelial integrity was studied by measurement of the percentage of vessel's circumference revealing CD34 endothelial marker. Results: 2 mg/ml papaverine concentration showed stronger vasodilatatory effect than 0.5 mg/ml, but it caused significantly higher endothelial damage. Response to KCl was 7.35±3.33 mN for vessels protected with papaverine 0.5 mg/ml and 2.66±1.96 mN when papaverine in concentration of 2 mg/ml was used. The histological examination revealed a significant difference in the presence of undamaged endothelium between vessels incubated in papaverine 0.5 mg/ml (72.86±9.3%) and 2 mg/ml (50.23±13.42%), P=0.002. Conclusion: Papaverine 2 mg/ml caused the higher endothelial damage. Concentration of 0.5 mg/ml caused better preservation of the endothelial lining.

Radial artery occlusion with a kaolin-filled pad after transradial cardiac catheterization.

Radial artery occlusion (RAO) occurs in 2% to 18% of patients after transradial access (TRA) cardiac catheterization. Using a kaolin-filled pad (QuikClot) reduces compression time during TRA and might reduce RAO. We examined the RAO risk with the kaolin-filled pad after TRA cardiac catheterization.This was a prospective cross-sectional study of 260 patients who underwent TRA cardiac catheterization in a cardiac ward of a Medical Center from 2012 to 2016. Patients were randomly assigned to 1 of 2 groups: the case group (n = 130) was postoperatively treated with a kaolin-filled pad, and the control group (n = 130) was treated with conventional hemostasis. Color duplex ultrasound was used to evaluate the 24-hour and 1-month postoperative radial artery flow velocity, diameter, patency, and RAO risk.RAO risk was not significantly different between the case and control groups after 24 hours (4.6% vs 5.4%, P = .776) or after 1 month (5.4% vs 6.1%, P = .789), regardless of whether it was a first TRA cardiac catheterization (after 24 hours [P = .153] or after 1month [P = .617], respectively) or a repeated TRA cardiac catheterization (after 24 hours [P = .754] or after 1month [P = .753], respectively).Using a kaolin-filled pad after TRA cardiac catheterization did not significantly reduce RAO risk compared with conventional hemostasis.

The effects of facemasks on airway inflammation and endothelial dysfunction in healthy young adults: a double-blind, randomized, controlled crossover study.

BACKGROUND: Facemasks are increasingly worn during air pollution episodes in China, but their protective effects are poorly understood. We aimed to evaluate the filtration efficiencies of N95 facemasks and the cardiopulmonary benefits associated with wearing facemasks during episodes of pollution. RESULTS: We measured the filtration efficiencies of particles in ambient air of six types of N95 facemasks with a manikin headform. The most effective one was used in a double-blind, randomized, controlled crossover study, involving 15 healthy young adults, conducted during 2 days of severe pollution in Beijing, China. Subjects were asked to walk along a busy-traffic road for 2 h wearing authentic or sham N95 facemasks. Clinical tests were performed four times to determine changes in the levels of biomarkers of airway inflammation, endothelial dysfunction, and oxidative stress within 24 h after exposure. The facemasks removed 48-75% of number concentrations of ambient air particles between 5.6 and 560 nm in diameter. After adjustments for multiple comparison, the exhaled nitric oxide level and the levels of interleukin-1α, interleukin-1ß, and interleukin-6 in exhaled breath condensate increased significantly in all subjects; however, the increases in those wearing authentic facemasks were statistically significantly lower than in the sham group. No significant between-group difference was evident in the urinary creatinine-corrected malondialdehyde level. In arterial stiffness indicators, the ejection duration of subjects wearing authentic facemasks was higher after exposure compared to the sham group; no significant between-group difference was found in augmentation pressure or the augmentation index. CONCLUSIONS: In young healthy adults, N95 facemasks partially reduced acute particle-associated airway inflammation, but neither systemic oxidative stress nor endothelial dysfunction improved significantly. The clinical significance of these findings long-term remains to be determined. TRIAL REGISTRATION: The trial registration number (TRN) for this study is ChiCTR1800016099 , which was retrospectively registered on May 11, 2018.

Alteration in the availability of epoxyeicosatrienoic acids contributes with NO to the development of endothelial dysfunction in conduit arteries during aging.

BACKGROUND AND AIMS: The mechanisms involved in endothelial dysfunction in humans during aging are largely unknown at the level of conduit arteries. We aimed to asses the role of NO and CYP450 epoxygenases-derived epoxyeicosatrienoic acids (EETs) in the regulation of endothelium-dependent flow-mediated dilatation of conduit arteries during aging. METHODS: Radial artery diameter and mean wall shear stress were determined by echotracking coupled with Doppler in 83 subjects (19-71 years old) during a sustained flow increase induced by hand skin heating, with the brachial infusion of saline or NO-synthase and cytochrome P450 epoxygenase inhibitors (L-NNMA and fluconazole respectively). Local blood sampling was performed for the quantification of NO metabolite nitrite and EETs. RESULTS: The magnitude of flow-mediated dilatation was independently and negatively correlated with age, baseline artery diameter and systolic blood pressure, and positively correlated with the increase in shear stress induced by heating. There was an increase in nitrite level during heating until the age of 35-40 years, which declined thereafter. However, the inhibitory effect of L-NMMA on flow-mediated dilatation progressively decreased during aging, demonstrating a decrease in functional NO availability. Moreover, aging progressively reduced the increase in EET level during heating as well as the inhibitory effect of fluconazole on flow-mediated dilatation. CONCLUSIONS: These results show that aging impairs the availability of EETs and NO and epoxyeicosatrienoic acids in peripheral conduit arteries, contributing to the development of endothelial dysfunction.

Comparison of Verapamil versus Heparin as Adjunctive Treatment for Transradial Coronary Procedures: The VERMUT Study.

OBJECTIVE: We sought to demonstrate that the combination of a local vasodilator (verapamil), modern materials, patent hemostasis, and intravenous anticoagulant only in the case of percutaneous coronary intervention, as compared to default heparin administration after sheath insertion, may optimize a combined endpoint, including radial artery oc-clusion (RAO), radial artery spasm (RAS), and access site complication. METHODS: This is a prospective, single-center, double-blind randomized trial. Overall, 418 patients undergoing a transradial approach (TRA) for coronary procedures were randomized 1: 1 to receive intraradial verapamil (5 mg) or heparin (5,000 IU) after a 6-Fr sheath insertion. The primary outcome was the 24-h occurrence of RAO (ultrasound confirmation), access site complication, and RAS requiring the bailout administration of vasodilators. RESULTS: The combined primary outcome occurred in 127 (30%) patients. It was significantly lower in patients randomized to verapamil as compared to others (26 vs. 35%, p = 0.03). This was mainly due to a significant reduction in RAS (3 vs. 10%, p = 0.006). The 24-h and 30-day occurrence of RAO did not differ between the study groups. CONCLUSION: Local administration of verapamil versus heparin reduces RAS, without increasing RAO, which appears to be strictly related to radial artery diameter and hemostasis time.