PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Radial Artery”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Left internal thoracic artery-radial artery composite grafts as the technique of choice for myocardial revascularization in elderly patients: a prospective randomized evaluation.

OBJECTIVES: The technique of choice for myocardial revascularization in elderly patients remains a debated issue. We evaluated the potential advantages of the use of left internal thoracic artery-radial artery composite grafts compared with conventional coronary artery bypass grafts in elderly patients. METHODS: We prospectively enrolled 160 patients aged more than 70 years scheduled to undergo isolated myocardial revascularization. Patients were assigned at random to group 1, 80 patients undergoing total arterial revascularization (left internal thoracic artery on left anterior descending coronary artery plus radial artery), or group 2, 80 patients undergoing standard coronary artery bypass graft surgery (left internal thoracic artery on left anterior descending coronary artery plus saphenous veins). The radial artery was used in all cases as a composite Y-graft. RESULTS: Preoperative characteristics and risk factors (EuroSCORE: group 1 = 7.9 vs group 2 = 8.1), number of grafted coronary vessels (group 1 = 2.4 vs group 2 = 2.5), aortic crossclamping time (group 1 = 37 +/- 7 minutes vs group 2 = 38 +/- 7 minutes), ventilation time (group 1 = 22 +/- 12 hours vs group 2 = 23 +/- 11 hours), intensive care unit stay (group 1 = 39 +/- 10 hours vs group 2 = 40 +/- 9 hours), and hospital mortality (group 1 = 3.8% vs group 2 = 5%) were comparable between the groups. Comparison between the 2 groups in terms of early postoperative complications showed a higher incidence of cerebrovascular accidents in group 2 (group 1 = 0 patients vs group 2 = 4 patients, 5%). At a mean follow-up of 16 +/- 3 months, patients in group 1 showed superior clinical results with a lower incidence of graft occlusion (group 1 = 2 vs group 2 = 11; P =.06) and angina recurrence (group 1 = 2 patients vs group 2 = 12 patients; P =.03). Multivariate analysis identified saphenous vein grafts as independent predictors for graft occlusion and angina recurrence. CONCLUSIONS: Left internal thoracic artery-radial artery composite grafts proved to be a safe procedure in elderly patients. It improved the clinical outcome, providing a significantly higher graft patency rate and a lower incidence of late cardiac events.

Age Factors↗

Inhibitory activity of clinical thiazolidinedione peroxisome proliferator activating receptor-gamma ligands toward internal mammary artery, radial artery, and saphenous vein smooth muscle cell proliferation.

BACKGROUND: The proliferation of vascular smooth muscle cells (VSMCs) is a known response to arterial injury that is an important part of the process of restenosis and atherosclerosis. People with diabetes have an increased risk of cardiovascular disease resulting from accelerated coronary atherosclerosis. The newest drugs for Type 2 diabetes are thiazolidinediones, which are insulin-sensitizing peroxisome proliferator activating receptor-gamma (PPARgamma) ligands. We investigated the antiproliferative effects of troglitazone, rosiglitazone, and pioglitazone on VSMCs derived from the three vascular beds used for coronary artery by-pass grafting: the internal mammary and radial artery and saphenous veins. METHODS AND RESULTS: The three vessels yielded proliferating cells of slightly differing morphology. Inhibition of cell proliferation was assessed by cell counting and cell cycle studies by Western blotting for phosphorylated retinoblastoma protein. All three thiazolidinediones showed inhibitory potency toward cell proliferation with a potency troglitazone>rosiglitazone approximately pioglitazone, and this potency profile was maintained toward the growth factor and insulin-stimulated phosphorylation of the retinoblastoma protein, which controls cell cycle progression. CONCLUSIONS: The inhibitory potency of clinical thiazolidinediones toward different vascular sources is dependent on the individual thiazolidinedione and very little on the vascular source.

Becaplermin↗

An unusual course of the radial artery.

Radial artery variations are of importance for clinicians, whether in angiographic examinations or surgical approaches. The high origin radial artery is the most frequent arterial variation observed in the upper limb, showing an incidence of 14.27% in dissection material and 9.75% in angiographic examination. In the present study an unusual course of the radial artery and its relation with the median nerve has been evaluated. During embryological development the radial artery sprouts from two arterial buds arising from the lateral side of the brachial artery and coalescing with each other. The artery lies in the forearm and is overlapped by the brachioradial muscle. In this particular case the radial artery originated from the medial side of the brachial artery and crossed the median nerve twice in an unusual manner 8 cm below the point at which the deep brachial artery arose and 12 cm above the intercondylar line. These results will enhance anatomical knowledge of the region and reduce complication in surgical approaches.

Brachial Artery↗

Vasorelaxant properties of isolated human radial arteries: comparison with internal mammary arteries.

Radial arteries, used in revascularisation surgery, are prone to spasm. We have examined the ability of nitrovasodilators, calcium channel blockers, and K(ATP) channel openers to cause vasodilation, and to attenuate contractions due to depolarisation and receptor activation in radial and mammary arteries used in coronary artery bypass graft surgery. Two to three millimetre rings of artery obtained from patients at surgery were studied in organ baths in vitro. Constriction to KC1 and phenylephrine was examined before and again after treatment of the rings with drug or vehicle. Calcium channel blockers were the only compounds to inhibit contractions to both KC1 and phenylephrine. Sodium nitroprusside attenuated constriction to phenylephrine but not KC1 in both vessels. K(ATP) channel openers similarly attenuated constriction to phenylephrine in radial arteries but were much less effective in mammary arteries. These studies support the continued use of calcium blockers after revascularisation with radial artery but suggest that other classes of drug may be as effective at minimising spasm due to receptor mediated constriction.

Adult↗

The induction of heme oxygenase 1 decreases contractility in human internal thoracic artery and radial artery grafts.

OBJECTIVE: Spasm remains a potential problem encountered during the use of arterial grafts in coronary artery bypass surgery. Heme oxygenase plays a role in the control of arterial vasoreactivity. Heme oxygenase exists in 2 constitutive isoforms (heme oxygenase 2 and 3) and an inducible isoform (heme oxygenase 1). The aim of our study was to induce heme oxygenase 1 by using hemin in human internal thoracic and radial arteries and to evaluate the effect of this induction on the contractility of these arterial grafts. METHODS: Segments of human arterial grafts obtained from patients undergoing isolated coronary artery bypass surgery were incubated in organ chambers for 4 hours in the presence of 10(-4) mol/L hemin. Concentration-response curves to norepinephrine were obtained in control and hemin-treated arterial rings. Heme oxygenase 1 expression was evaluated by using enzyme-linked immunosorbent assays and immunohistochemical staining. RESULTS: The contractility of the arterial rings to norepinephrine was significantly reduced after incubation with hemin. Zinc protoporphyrin (an inhibitor of heme oxygenase) reversed the effect of hemin, whereas the inhibitor of nitric oxide synthase had no effect. The inhibitor of soluble guanylate cyclase blocked the decrease in contractility induced by hemin. Immunohistochemical staining revealed a large expression of heme oxygenase 1 in all vascular layers of hemin-treated internal thoracic artery and radial artery rings. Enzyme-linked immunosorbent assay studies showed a significant increase in heme oxygenase 1 levels in hemin-treated internal thoracic artery and radial artery rings. CONCLUSION: Hemin caused in vitro induction of heme oxygenase 1 in human internal thoracic artery and radial artery grafts. This induction resulted in a reduced contractility to norepinephrine, partially through the cyclic guanosine monophosphate-dependent pathway. This effect was independent from nitric oxide synthesis.

Coronary Artery Bypass↗

Total myocardial revascularization with arterial conduits: radial artery combined with internal thoracic arteries.

OBJECTIVE: We prospectively tested the feasibility of achieving total arterial revascularization with the use of the radial artery to revascularize the circumflex, diagonal, and right coronary arteries combined with a left internal thoracic artery graft to the left anterior descending artery and, in some cases, a right internal thoracic artery graft to the right coronary artery. METHODS: In 164 patients, the radial artery was used as a free Y or T graft from the left internal thoracic artery. Of 568 grafts (3.5 +/- 1 [standard deviation] per patient), 296 (1.8 +/- 0.8 per patient) were constructed with the radial artery as single grafts or as double, triple, or quadruple sequential anastomoses to the circumflex, diagonal, and posterior descending arteries. Diltiazem was administered to prevent spasm. Forty-six patients underwent coronary angiography before discharge from the hospital. Follow-up time was 1 to 19 (9.5 +/- 6.1) months. RESULTS: Total arterial revascularization was achieved in 137 patients (83.5%). Three (1.8%) died postoperatively of sepsis, ventricular fibrillation, and heart failure, respectively. Three (1.8%) had postoperative myocardial infarction. No hand ischemia occurred. Angiography showed patency of all arterial conduits. Radial artery spasm appeared in 3 (6.5%) of 46 angiograms. Two patients (1.2%) died during the follow-up period of pneumonia and gastrointestinal tract bleeding, respectively. No other events or reoperations occurred, and 95.1% of the patients are free of symptoms. CONCLUSIONS: The radial artery, as a free Y or T graft from the left internal thoracic artery to the circumflex, diagonal, and right coronary arteries, permits total arterial revascularization with excellent patency rates, minimal morbidity and mortality, and no need for reoperation. Longer follow-up times are necessary to draw definitive conclusions.

Coronary Angiography↗

Total arterial revascularization with an internal thoracic artery and radial artery T graft.

BACKGROUND: Proximal anastomosis of the radial artery to the side of the internal thoracic artery (ITA) permits complete arterial revascularization in most patients, with the aim of improving long-term results of coronary artery bypass through greater long-term graft patency. The short-term results, however, have yet to be defined. We therefore reviewed our early experience with this grafting strategy. METHODS: Between October 1, 1993, and September 1, 1998, 649 patients aged 30 to 85 years (mean, 60+/-10 years) had primary coronary artery bypass using an ITA and radial artery in a T-graft configuration. Left ventricular function was severely depressed (ejection fraction <35%) in 12%, and left main stenosis was present in 14%. RESULTS: A total of 937 distal anastomoses were performed with the left ITA (1.4 per patient) and 1,452 with the radial artery (2.2 per patient). There was one perioperative death (0.2%). There were 32 (5%) q-wave myocardial infarctions, and 14 patients (2%) had transient low output syndrome. There was one episode of hypoperfusion corrected by lengthening the left ITA. Angiography for clinical indications in 27 patients 1 to 35 months postoperatively (mean, 9.5+/-8.3 months) demonstrated a distal anastomotic patency of 100% for ITA and 82% for radial artery grafts. CONCLUSIONS: Complete arterial revascularization can be achieved with an ITA and radial artery T-graft with low operative risk and acceptable early patency. These results support the continued investigation of this grafting strategy.

Adult↗

Coronary revascularization with the left internal thoracic artery and radial artery: comparison of short-term clinical evolution between elective and emergency surgery.

BACKGROUND: Left internal thoracic artery-to left anterior descending artery grafting has become a fundamental part of coronary artery bypass grafting. This grafting has led to increased use of other arterial conduits, of which the radial artery is most popular. Whether radial grafting can be used in the emergency patient is not known. This study compares the short-term clinical evolution between elective vs emergency coronary artery bypass grafting surgery with left internal thoracic artery and radial artery. METHODS: A retrospective study of 47 patients who underwent elective or emergency coronary artery bypass grafting from 1996 to 2003. All patients had coronary stenosis>70% in all target vessels. Only the left internal thoracic artery and radial artery were used as grafts. Patients were divided into elective group (23 patients) and emergency group (24 patients). Emergency criteria were unstable angina and/or critical coronary stenosis with high risk for acute myocardial infarction. Groups were similar for age and number of diseased vessels. RESULTS: The mean number of left internal thoracic artery grafts per patient in the elective and emergency groups were respectively 1.17 and 1.38 (P=.17). The mean number of radial artery grafts per patient in the elective and emergency groups was respectively 2.26 and 2.08 (P=.48). The 30-day mortality was 0. There was no postoperative cardiogenic shock. The elective group had 1 acute myocardial infarction (4.4%) postoperatively, and emergency group had 5 (20.8%). A nonsignificant trend towards acute myocardial infarction was noted in the emergency group (P=.18). Intensive care unit and postoperative stay were similar in both groups. CONCLUSION: Coronary artery bypass grafting using left internal thoracic artery and radial artery accomplishing complete revascularization can be performed in emergency patients with results similar to those for elective patients.

Coronary Artery Bypass↗

Laser Doppler flowmetry assessment of microcirculation in upper extremities before and in long-term period after harvesting of radial artery.

Radial artery (RA) is rather commonly used as a graft for autoarterial myocardial revascularization. Consequences of RA harvesting for the development of ischemic disturbances in distal hand segments are poorly understood. The paper presents assessment of hand microcirculation (HMC) before and in late postoperative period after RA harvesting with modern precise diagnostic method - laser Doppler flowmetry (LDF). LDF assessment of HMC was carried out in 80 patients with ischemic heart disease (160 hands) to evaluate the possibility of RA harvesting for coronary artery bypass surgery. HMC classification was developed on the base of these measurements: type 1 -normocirculatory HMC: 6.7-17 ml/min/100 g (58%); type 2 - vasospastic HMC: < or = 6.7 ml/min/100 g (20%); type 3 - hyperemic HMC: > or = 17 ml/min/100 g (22%). In 34% of cases preoperative examination revealed microcirculatory asymmetry between right and left hands. Based on preoperative examination results in 22.9% of cases the decision was made to refuse from RA excision because of positive collateral circulation test developed in our Institute (positive decision about Patent award according to appeal No2000122582/14 (023905) from 28.08.2000). In 14 patients (14 upper extremities) HMC was measured before and 1-1.5 years after RA harvesting. After RA excision baseline HMC in operated hand reduced significantly while maximal HMC reserve remained at the level close to preoperative one. Postoperative HNMC alterations evidence of adequate preoperative assessment of hand collateral circulation potential. In case of blood flow asymmetry RA must be taken from the hand with higher blood supply and adequate collateral microcirculation.

Arteriovenous Shunt, Surgical↗

Analysis of vasoreactivity of isolated human radial artery.

Radial artery (RA) is increasingly used as graft for coronary artery bypass grafting due to its good long-term patency. However, the mechanism of peri- and post-operative spasm is still unclear. Because of that, the aim of our study is to analyze the contractility of RA and to determine whether the presence of functional endothelium alters its contractile properties. Contractions of isolated RA rings were provoked by exogenously applied vasoconstrictors or by electrical field stimulation (EFS, 20 Hz). The order of vasoconstrictors potency based on their EC50 values was as follows: angiotensin II > phenylephrine > 5-hydroxytriptamine. Presence of endothelium increased both EC50 and maximal contraction to phenylephrine and angiotensin II, but inhibited reactivity of RA to 5-hydroxytriptamine. Spontaneous rhythmic contractions (SRC, <4 mHz) and EFS-induced contractions of RA are endothelium-independent and weaker than contractions induced by exogenously applied vasoconstrictors. Our study concludes that RA shows marked sensitivity and reactivity to angiotensin II, phenylephrine, and 5-hydroxytriptamine. Further investigations are necessary to answer why angiotensin II and phenylepehrine induce stronger contractions in the presence of endothelium. In addition, SRC as well as contractions of neurogenic origin may take part in developing vascular spasm of RA.

Angiotensin II↗

T grafts with the right internal thoracic artery to left internal thoracic artery versus the left internal thoracic artery and radial artery: flow dynamics in the internal thoracic artery main stem.

OBJECTIVE: Complete arterial coronary artery bypass grafting with 2 grafts can be achieved even in triple vessel disease by use of a T configuration. There is still uncertainty whether the coronary flow reserve in the main stem of the left internal thoracic artery is sufficient to supply more than 1 anastomosed coronary vessel. METHODS: Between March 1996 and February 1999, 251 patients with multivessel coronary artery disease underwent complete arterial revascularization with T grafts, using either the left internal thoracic artery with the free right internal thoracic artery graft (n = 73, group I) or the left internal thoracic artery and radial artery (n = 178, group II). A mean of 4.0 (group I) versus 4.3 (group II) coronary vessels were anastomosed per patient. One week (n = 92) and 6 months (n = 28) after the operation, flow was measured in the proximal left internal thoracic artery with a Doppler guide wire. Maximum flow was determined after injection of adenosine (30 microg). RESULTS: The in-hospital mortality was 2.7% (group I) versus 2.3% (group II). At angiography (n = 142, 56.6%) the patency rate was 96.3% (group I) versus 98.2% (group II). There was no significant difference between baseline flow, maximum flow, and coronary flow reserve between the 2 groups. Coronary flow reserve increased in both groups within the first 6 postoperative months (group I, 1.85 +/- 0.31 vs 2.77 +/- 0.77, P =.0002; group II, 1.82 +/- 0.4 vs 2.53 +/- 0.73, P =.009). CONCLUSION: Both variants of T grafts allow for complete arterial revascularization with good perioperative results. The flow reserve of the proximal internal thoracic artery is adequate for multiple coronary anastomoses irrespective of the choice of the second arterial graft.

Blood Flow Velocity↗

The left internal thoracic artery and radial artery composite graft in off-pump coronary artery bypass grafting.

Arterial multivessel bypass grafting without extra corporeal circulation and manipulation of the ascending aorta should be a good surgical option for the treatment of coronary artery disease. An internal thoracic artery (ITA)-radial artery (RA) composite graft was used for this purpose. Between July 2000 and October 2001, we employed the LITA-RA composite graft for off-pump coronary artery bypass in 15 cases. Mean patient age was 71.3 +/- 5.8 years old. Left main trunk disease was present in six patients and triple-vessel disease in four patients. Preoperative concomitant disease was renal dysfunction in three cases, cerebrovascular disease in four and diabetes mellitus in five cases. Two patients had a so-called bad aorta. Twelve elective operations and three urgent operations were carried out for unstable angina. Two to four (mean 2.6 +/- 0.7) anastomoses were performed per patient. Complete revascularization was achieved in 12 out of 15 patients. Mean operating time was 335 +/- 53 min. Mean intraoperative blood loss was 595 +/- 375 ml and nine patients underwent the operation without blood transfusion. There was no PMI, no brain disorder, and no death. Postoperative coronary angiography in all patients documented a good patency rate (LITA 15/15, RA 21/21, right gastroepiploic artery (RGEA) 2/2, and saphenous vein graft (SVG) 0/2). LITA-RA composite grafting in off-pump coronary artery bypass enables arterial multivessel revascularization using an aortic no touch technique. This can be done with minimum postoperative complications and without risk of cerebral infarction even in patients at high risk for extracorporeal circulation (ECC).

Aged↗

Total arterial revascularization with internal mammary artery or radial artery pi graft configuration.

To investigate the clinical use of pi graft in total arterial revascularization and its outcomes, a retrospective analysis of 23 patients out of 1000 patients undergoing total arterial coronary bypass surgery with a pi graft between September 1994 and December 2004 was performed. In the selected patients for the management of triple vessel disease with middle diagonal/intermediate ramus disease such that a skip with the left internal mammary artery (LIMA) or radial artery (RA), the main stem of pi graft, to the left anterior descending coronary artery (LAD) will not work and the right internal mammary artery (RIMA) or right gastroepiploic artery (RGEA) cannot pick up the diagonal/intermediate ramus, hence the LAD and diagonal/intermediate ramus were grafted with a mini Y graft using the distal segment of LIMA, RIMA, RA or RGEA, together with the bilateral internal mammary artery (BIMA) or LIMA-RA T graft to compose pi graft. Twenty-three patients (18 males, 5 females) underwent the pi graft procedure. There were no deaths or episodes of myocardial infarction, stroke, and deep sternal wound infection. One patient required reopening for controlling bleeding. Until the end of 2004, during a mean follow-up of 81.0 +/- 28.4 months, no angina needing re-intervention or operative therapy or coronary related death occurred. In conclusion, in patients with specific coronary artery anatomy/stenosis, the BIMA (sometimes LIMA with RA or RGEA) pi graft can be successfully performed for total arterial revascularization with good midterm outcomes.

Aged↗

Effect of target artery location and severity of stenosis on mid-term patency of aorta-anastomosed vs. internal thoracic artery-anastomosed radial artery grafts.

OBJECTIVE: To verify the effect of location and severity of stenosis of the target coronary artery (TCA) on mid-term patency of aorta-anastomosed vs. internal thoracic artery (ITA)-anastomosed radial artery (RA) graft. METHODS: During a 3-year period 228 consecutive patients received an RA graft at our institution. In 131 cases the RA was anastomosed to the aorta whereas in 97 the proximal anastomosis was performed on a mammary graft. The two groups were comparable in terms of preoperative variables and TCA characteristics. At a mean follow-up of 6.5 years 128 cases of the aorta-anastomosed and 95 of the mammary-anastomosed group were submitted to control angiography. RESULTS: Mid-term patency and perfect patency rates were 92.1 and 89.8% (118/128 and 115/128) for aorta-anastomosed RA vs. 86.3 and 84.2% for mammary-anastomosed grafts (82/95 and 80/95; P=0.81 and 0.82). The location of TCA did not influence graft patency in the two groups. The severity of the TCA stenosis strongly influenced graft patency in both groups but the threshold for failure was clearly higher in the mammary-anastomosed group. CONCLUSIONS: ITA-anastomosed RA grafts are more vulnerable to the detrimental effect of chronic native competitive flow and should be used only for target vessel with subocclusive stenosis. The location of the distal anastomosis does not influence long-term RA patency.

Aorta↗

Right internal mammary artery and radial artery composite in situ pedicle graft in coronary artery bypass grafting.

BACKGROUND: The use of two internal mammary artery grafts in coronary artery bypass grafting has been associated with decreased risks of death, reoperation, and angioplasty. However, bilateral internal mammary artery takedown is associated with higher incidence of sternal wound infection, particularly in people with diabetes and in elderly and obese patients. This study was conducted to explore the feasibility of using right internal mammary artery (RIMA) and radial artery (RA) as a composite graft while preserving the distal two thirds of the RIMA to leave the sternal blood supply intact. METHODS: Eighteen patients underwent coronary artery bypass grafting using proximal RIMA and RA composite graft as one of the bypass conduits. The distal two thirds of the RIMA was left intact to preserve sternal blood supply. The graft-free flows of the RIMA and RA composite graft and of the left internal mammary artery graft and the length of the composite graft had been measured. The graft patency and the flow in the distal part of the unharvested RIMA was evaluated postoperatively 2 weeks after the procedure. In 6 of these patients the graft patency was evaluated by selective angiography. RESULTS: There was no hospital mortality or incidence of perioperative myocardial infarction. None of the patients needed intraaortic balloon pump support postoperatively. There was no sternal wound infection. The vessels grafted were distal right coronary artery (n = 7), posterior descending artery (n = 8), obtuse marginal branches (n = 3), and posterolateral ventricular branch (n = 1); 1 patient received the composite graft as a sequential graft to the posterior descending artery and posterolateral left ventricular branches. The mean graft-free flow of the RIMA and RA composite graft was 98.06 +/- 16.93 mL/min compared to left internal mammary artery flows of 55.80 +/- 8.99 mL/min. All 16 patients who had a good echo window showed patent grafts when evaluated by two-dimensional echocardiography and color Doppler echocardiography. All of the 6 patients in whom the angiogram was repeated postoperatively showed patent RIMA and RA grafts. CONCLUSIONS: Myocardial revascularization using proximal RIMA and RA in situ pedicle graft was safe in patients with diabetes and in obese and chronic obstructive pulmonary disease patients. This graft was useful to revascularize posterior descending artery, posterolateral ventricular branches of right coronary artery, and obtuse marginal branches where a left internal mammary artery and RA composite graft cannot be used because of technical reasons. Its usage was not associated with sternal wound infection.

Aged↗

Vasorelaxation induced by vascular endothelial growth factor in the human internal mammary artery and radial artery.

OBJECTIVES: Due to potential therapeutic value of vascular endothelial growth factor (VEGF) in coronary artery disease, the effect and mechanism of VEGF in human arteries used as coronary bypass grafts become important but not fully understood. VEGF-mediated endothelial regulation in vasorelaxation was studied in internal mammary artery (IMA) and radial artery (RA), compared with that of the classical agent-acetylcholine (ACh). The role of nitric oxide (NO), prostacyclin (PGI2), and endothelium-derived hyperpolarizing factor (EDHF) was investigated. METHODS: VEGF- and ACh-induced responses were measured in RA and IMA with or without endothelium and in the absence or presence of inhibitors of nitric oxide synthase or prostacyclin. In addition, the VEGF-induced PGI2 was measured by enzyme immunoassay. RESULTS: VEGF induced similar relaxation in RA (59.2+/-9.3%) and IMA (56.1+/-6.4%) that was significantly inhibited by N(omega)-nitro-L-arginine (L-NNA) plus oxyhemoglobin (HbO) (IMA: 24.9+/-4.3%, P=0.03 vs. RA: 25.0+/-8.6%, P=0.01) or by indomethacin (INDO) (IMA: 21.8+/-2.5%, P=0.000 vs. RA: 30.0+/-6.6%, P=0.04) with more inhibition in IMA than RA (P<0.05). In addition, the VEGF-induced PGI2 was significantly higher in IMA than RA (11.5+/-2.1 vs. 4.9+/-1.1 pg/ml/mg, P=0.002). INDO+L-NNA+HbO reduced the VEGF-induced relaxation to 20.8+/-4.6% in RA vs. 4.8+/-1.6% in IMA (P=0.01). In contrast, the maximal relaxation induced by ACh in RA (55.9+/-6.0%) and IMA (48.5+/-5.3%) was largely inhibited by L-NNA in IMA and RA (14.7+/-3.0%, P=0.000 vs. 15.2+/-3.2%, P=0.004) but little affected by INDO. CONCLUSIONS: VEGF induces similar relaxation in IMA and RA with significantly more PGI2-mediated relaxation and higher stimulated PGI2 level in IMA but more EDHF-mediated relaxation in RA. In comparison, ACh-induced relaxation mainly depends on NO. Thus, our study reveals a significant difference in the mechanism of the endothelium-dependent relaxation induced by VEGF and ACh.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

[Composite arterial conduits with internal thoracic artery and radial artery for a myocardial revascularization].

From April 1996 to December 1996, 15 patients were submitted to myocardial revascularization using composite arterial conduit with internal thoracic artery (ITA) and radial artery (RA). The age ranged from 51 to 76 years (mean age, 65.7 years); Forty patients were male. All patients had double or triple vessel disease or LMT disease. We used 28 arterial conduits including 15 left ITAs, 15 RA, 9 right gastroepiploic artery and one inferior epigastric artery. 15 RAs were anastomosed to LITAs and 15 composite arterial conduits were constructed (branched in 15). There was no operative deaths. Early postoperative angiographic controls demonstrated 93.3% (14/15) patency of composite grafts in 14 of 15 patients. The composite arterial graft using ITA and RA is feasible and the anastomoses so performed are completely safe.

Aged↗