PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “THORACIC ARTERIES”

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 451 records · Page 25Linked to original sources
PubMed1995

Distal flow determinants in canine myocardium perfused through internal thoracic artery bypass grafts.

The dynamic reactivity and the acute, recruitable flow capacity of an internal thoracic artery (ITA) graft remains unclear. These experiments were conducted in 20 anesthetized dogs with the left ITA grafted to the circumflex artery, off pump, using a brief local occlusion. The left main coronary artery was occluded, rendering the entire left ventricle, including anterior descending artery and circumflex regions, totally dependent on the ITA graft. When the left main coronary artery was occluded, the ITA flow immediately increased more than fivefold (93.4 +/- 9.6 mL/min; mean +/- standard deviation), representing an absolute flow value three times higher than ITA flow measured in situ on the chest wall (27.5 +/- 9.6 mL/min; p < 0.05 versus control), and the ITA graft provided total resting flow requirements (93.4 +/- 9.6 mL/min) for both left anterior descending and circumflex coronary artery perfusion territories at levels comparable with measured native flow values (y = (0.9555)x + 21.9272; r = 0.976; p < 0.05). Pharmacologic challenge with adenosine (0.2 mg.kg-1.min-1 intravenously) significantly increased the graft flow (120.3 +/- 18.7 mL/min; p < 0.05 versus control), but also significantly decreased the mean arterial pressure (85.4 +/- 5.0 versus 74.6 +/- 6.1 mm Hg; p < 0.05). Phenylephrine (0.003 mg.kg-1.min-1 intravenously) significantly decreased ITA graft flow (81.2 +/- 9.0 mL/min; p < 0.05 versus control) despite significantly increased perfusion pressure (84.8 +/- 6.3 versus 108.2 +/- 8.6 mm Hg; p < 0.05 versus control).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine↗
PubMed2005

Thoracic radiation therapy and suitability of internal thoracic arteries for myocardial revascularization.

INTRODUCTION AND BACKGROUND: Myocardial revascularization using internal thoracic arteries (ITAs) has been associated with superior clinical outcome. This study addresses the question of whether internal mammary arteries are unsuitable for grafting due to radiation-based damage in patients with history of thoracic radiation therapy. We review our experience in this subset of surgical candidates. PATIENTS AND METHODS: Forty-nine patients undergoing elective coronary artery bypass grafting with use of at least one ITA were enrolled and matched to 49 comparable nonirradiated individuals by propensity scoring system. Preoperative and postoperative data were collected and compared. A 18-month clinical follow-up was performed. RESULTS: Intraoperative mammary artery flow was assessed by transthoracic Doppler echocardiography probe, and there was no significant difference between irradiated and nonirradiated individuals (36 +/- 8.3 mL/min vs 39 +/- 7.2 mL/min, p = 0.15). The two study groups were also comparable in terms of survival (overall mortality, 2%) and recurrence of angina and perfusion defect at control stress perfusion nuclear scan (p = 0.99 and p = 0.77, respectively). One arterial graft showed stenosis at postoperative angiography. The dose of radiation therapy administered did not correlate with graft flow values after anastomosis. CONCLUSION: Our data suggest that the use of a monolateral or bilateral ITA is not associated with early graft failure in patients with history of chest/mediastinal irradiation. Skeletonization harvesting technique might be recommended because of the frequent presence of fibrous tissue around the in situ vessel. Arterial graft stenosis in thorax-irradiated patients should be attributed to the primary atherosclerotic disease rather than to irradiation itself.

Aged↗
PubMed2001

The impact of chronic renal failure on atherosclerosis of the internal thoracic arteries.

BACKGROUND: Little is known about the impact of renal failure on atherosclerotic changes in the internal thoracic artery (ITA). METHODS: A total of 20 consecutive patients on chronic dialysis who underwent coronary artery bypass grafting (CABG) during April 1998 through September 1999 were investigated. The 20 control patients were selected from the same interval to rigorously match risk factors. Atherosclerosis of the ITA collected from each patient was analyzed using the subjective evaluation proposed by Kay and colleagues. RESULTS: There were no cases of greater than 25% atherosclerotic luminal narrowing among a total of 35 ITA specimens from dialysis patients. The degree of atherosclerosis was not significantly different from that of the specimens from matched patients (p = 0.18). No calcification was found in ITA grafts either microscopically or macroscopically. The number of elastic lamellae, an index of the elasticity of the ITA graft, was not significantly different from those obtained from the matched patients. Analysis of preoperative coronary angiography revealed that coronary calcification was significantly more frequent in dialysis patients (15 patients, 75%) than in matched patients (p < 0.05). By analysis of postoperative angiography in dialysis patients, no evidence of atherosclerotic changes was found in 28 opacified ITAs. In addition, despite the presence of calcification in the native coronary, no calcification was evident along the entire length of the ITAs. CONCLUSIONS: This study revealed the minimal impact of chronic renal failure on atherosclerotic changes in the ITA. The results of this study support the continued use of ITA grafting in dialysis patients.

Aged↗
PubMed2002

Early angiographic and clinical results of branch conduits attached proximally to left internal thoracic arteries.

BACKGROUND: We assessed the characteristics of composite branch conduits attached proximally to an in-situ left internal thoracic artery (LITA). METHODS: Sixty nine patients underwent coronary artery bypass grafting (CABG) using composite branch conduits. Overall 35 distal LITAs, 4 RITAs, 18 radial artery grafts (RAG), and 13 inferior epigastric artery grafts (IEA) (both the distal LITA and IEA were used in one patient) were used. Clinical and angiographic results were assessed. RESULTS: Patency of branch conduit was 97.1% in distal LITAs, 100% in RITAs, 100% in RAGs, and 90.9% in IEAs. All in-situ LITAs were patent. Ten branch conduits exhibited the string sign. The string sign was caused by competitive flow in seven patients. In three of seven patients with competitive flow, the string sign had resolved at one year after operation as the proximal stenosis of the native coronary artery increased in severity. CONCLUSIONS: The results of CABG using branch conduits were satisfactory. It is feasible to observe and follow patients with composite grafts exhibiting the string sign in the absence of ischemia.

Coronary Angiography↗
PubMed1995

Color-flow duplex ultrasound assessment of internal thoracic artery graft after coronary bypass.

In an effort to develop a noninvasive method to evaluate flow characteristics of the internal thoracic artery (ITA) graft after coronary artery bypass grafting, we performed color-flow duplex ultrasound studies of the right and left ITAs of 42 patients before and 5 weeks after bypass grafting. The ITA was visualized with a duplex scanner (5.0-MHz probe) through the first or second intercostal space. We recorded the diameter, peak systolic velocity, and end-diastolic velocity for each patient. Preoperative measurements of the native ITAs were obtained easily in all patients. Postoperatively, the unused right ITA was seen in all patients. Postoperative visualization of the left ITA graft was adequate to make reliable measurements in 40 patients (95%). Postoperative end-diastolic velocities of the unused right ITA and the left ITA graft were markedly higher than the preoperative end-diastolic velocities of the native ITAs (p < 0.001). Whereas there was a marked increase in the peak systolic velocity of the postoperative unused right ITA (p < 0.05), the postoperative peak systolic velocity of the left ITA graft was significantly lower than the preoperative value (p < 0.001). We conclude that postoperative visualization of the left ITA graft is possible with the use of color-flow duplex ultrasound. Ultrasonic surveillance of postoperative ITAs may reveal ITA graft velocity abnormalities before overt graft failure is manifested in the patient who has undergone coronary artery bypass grafting.

Adult↗
PubMed1995

[The internal thoracic artery of poor quality: was cardiac massage a cause of ITA stenosis?].

The case of stenotic left internal thoracic artery (LITA), with a very rare and interesting histological findings is reported. The patient, a 65-year-old man, fell into shock, due to acute myocardial infarction and received cardiopulmonary resuscitation at home immediately. Three months later, patient underwent coronary artery bypass grafting. The LITA was dissected from the chest wall with a tissue pedicle by usual manner. However, it was abandoned to use for grafting, because of extremely poor blood flow even after balloon dilatation was noticed. Histological study revealed a significant granulation of LITA media, led to severe stenosis of LITA lumen on it's portion. On other side, either proximal and distal portion of LITA remained intact. It seems that this unusual histological change of LITA media developed after LITA over stretching due to cardiac massage during cardiopulmonary resuscitation. If patient, scheduled for coronary bypass surgery, has in a personal history the presence of cardiac massage, traffic accident, some contact sport or any other chest trauma, it is recommended to perform LITA angiography preoperatively, if an intention to use the LITA for coronary artery bypass grafting exists.

Cardiopulmonary Resuscitation↗
PubMed1998

Bilateral internal thoracic artery grafting may improve outcome of coronary artery surgery. Risk-adjusted survival.

BACKGROUND: Excellent clinical results of the patients with single left internal thoracic artery (ITA) grafting compared with saphenous vein grafting have prompted surgeons to use both ITAs. However, long-term benefits of the bilateral ITA grafting have not been proven. METHODS AND RESULTS: We reviewed our experience of 2826 patients (age 62 +/- 9 years [mean +/- 1 SD], 2350 men, mean follow-up 52 months) who underwent surgery with ITAs, supplemented by saphenous vein grafts when required, between 1985 and 1995. Single ITA grafting (n = 1557) was compared with double (n = 1269), by means of the Cox proportional hazards model. Significant predictors of all-cause mortality were as follows: (1) peripheral vascular disease, rate ratio (RR) = 2.4 (1.7 to 3.4 [95% CI]); (2) prior myocardial infarction, RR = 2.1 (1.5 to 3.1); (3) severe left ventricular dysfunction, RR = 3.9 (2.6 to 5.9) and moderate left ventricular dysfunction, RR = 2.0 (1.5 to 2.6); (4) age > or = 70 years, RR = 3.4 (2.4 to 4.8), and age 60 to 69 years, RR = 1.7 (1.3 to 2.4); (5) diabetes mellitus, RR = 1.7 (1.3 to 2.4); (6) carotid disease, RR = 1.7 (1.2 to 2.4); and (7) single ITA (versus bilateral ITA), RR = 1.4 (1.1 to 1.8). Number of vessels diseased, surgical status (i.e., urgent versus elective), hypertension, and sex were not significant predictors. Unadjusted actuarial survival rates at 10 years were 86 +/- 3% (mean +/- 95% CI) for bilateral ITA group and 71 +/- 5% for single ITA. Single ITA was also a predictor of all-cause mortality, late myocardial infarction, or late reoperation (RR = 1.3 [1.1 to 1.6]). CONCLUSIONS: Bilateral ITA grafting may improve long-term survival and freedom from late myocardial infarction or reoperation after coronary artery surgery. Mathematical modeling may assist in developing a strategy for use of bilateral ITA grafts.

Arteries↗
PubMed1996

Internal thoracic artery holder for coronary artery bypass grafting.

An arterial graft holder was designed to facilitate coronary artery bypass grafting using arterial conduits. It is possible to open the heel of the arterial conduit and stitch the most difficult angle of the anastomosis under optimal visualization. This internal thoracic artery holder is atraumatic and protects the arterial conduit wall from crush injuries caused by vascular forceps. Anastomosis without the endothelial injury may provide long-term patency of the coronary artery bypass graft.

Anastomosis, Surgical↗
PubMed2005

Comparison of the rheologic parameters in left internal thoracic artery grafts with those in saphenous vein grafts.

BACKGROUND: Left internal thoracic artery (LITA) grafts have superior patency to saphenous vein grafts (SVG). Because shear stress augments the release of nitric oxide throughout the LITA endothelium, shear stress and shear rate in coronary artery bypass grafts (CABG) may play an important role in the higher patency, so the aim of the present study was to evaluate and compare the rheologic parameters in CABG using LITA and SVG. METHODS AND RESULTS: Rheologic examinations were done in 197 patients using a vacuum-suction glass tube viscometer after CABG surgery was completed. Shear stress and shear rate were calculated from the geometry of the graft, blood flow in the graft and blood viscosity. Of 197 patients, 177 underwent LITA grafting to the left anterior descending artery (LAD) and 160 had SVG anastomosis to coronary arteries. Mean wall shear stress in the LITA grafts to the LAD (13.8+/-1.0 dyne/cm2) was nearly 4-6-fold larger than that in the SVG grafts. Mean shear rate (559.1+/-57.0 s(-1)) of LITA-LAD grafts was approximately 2-3-fold higher than that of SVG. CONCLUSION: These results suggest that high wall shear stress and shear rate play an important role in the higher patency rate of LITA grafts.

Aorta, Thoracic↗
PubMed2001

Bilateral origin of the internal thoracic artery from the third part of the subclavian artery: a case report.

The routine use of the internal thoracic artery (ITA) as a conduit in coronary artery bypass grafting surgery has highlighted the need to appreciate this vessel's anatomic variations. The usual origin of this vessel is from the first part of the subclavian artery, occasionally from the second and rarely from the third. Henriques-Pino and Prates described a unilateral origin from the third part on the left and Vorster et al on the right. Our cadaveric case report presents an unusual bilateral origin of the ITA arising from the third part of the subclavian artery in a 25-year-old Black South African female. The ITA arose from the ventral aspect, 7.3 cm on the right side and 8.5 cm on the left side from the origin of the subclavian artery, and inclined acutely inferiorly and medially, anterior to the distal attachment of the scalenus anterior m., followed the inner border of the first rib for a short distance and, thereafter, continued its usual course in the thorax. This appears to be the first case report presenting a bilateral origin of the ITA from the third part of the subclavian artery.

Adult↗
PubMed1999

[PTCA of the LAD via the internal thoracic artery graft with Doppler ultrasonic control of the results: a case report and review of the literature].

The report presents a transluminal angioplasty (PTCA) of a severe stenosis of the left anterior descending artery (LAD) behind the anastomosis; the internal thoracic artery (ITA) graft was used as a conduit. Before and after the PTCA the changing of velocity flow patterns under rest and stress conditions with a handgrip-maneuver were measured with a noninvasive transthoracic ultrasound Doppler system. The mean diastolic velocity, which represent coronary perfusion through the ITA graft, increased after successful PTCA at rest and under stress conditions. An additional increasing of the mean diastolic velocity at rest and under stress conditions was seen after six months before the catheterization proposing no signs of restenosis. For this reason the vessel could be classified prospectively patient. This could be confirmed during coronary angiography. We also present a review of the published reports concerning PTCA of ITA grafts and PTCA of the native vessel using the ITA as a conduit. In this review 286 cardiac interventions on 273 patients with a primary rate of success of 87% could be counted, the documented rate of restenosis was 30%, and the rate of complication was approximately 1%. The PTCA in ITA grafts or of the native vessel via ITA grafts, respectively, represent an alternative to reoperation. The ultrasound-duplex measurements are gaining an increasing significance for the noninvasive patency rate and post-interventional monitoring of the long-term PTCA result. With the augmentation of the ITA as a coronary bypass and expected increase of post-operative interventions, a noninvasive tool is necessary.

Angina Pectoris↗
PubMed2003

Early results of complete off-pump coronary revascularization using left internal thoracic artery with composite radial artery.

OBJECTIVE: Off-pump coronary artery bypass (OPCAB) using the left internal thoracic artery (LITA) with a composite radial artery (RA) was employed for arterial revascularization in order to minimize neurological complication. METHODS: Sixty-one patients underwent OPCAB using the LITA with a composite RA. Angiography was performed in all patients at two weeks postoperatively. RESULTS: The mean number of distal anastomoses was 3.2 +/- 0.4. A Y-composite graft was used in 55 patients, and K-composite graft was used in the other 6 patients. There was no hospital death, no neurological complication nor deep sternal infection. Furthermore, there was no episode of perioperative myocardial infarction nor hypoperfusion syndrome. Patients have been angina-free during a mean follow-up period of 1 year. The graft patency of the LITA to the left anterior descending artery (LAD) was 100% (61/61 anastomoses). The RA became occluded in 4 patients, and the patency rate was 95.6% (130/136 anastomoses). String or coronary-coronary bypass resulting from flow competition was observed in the LITA of 6 patients and in the RA of 13 patients. The string of the LITA occurred in the segment distal from the anastomosis with the composite RA. The string or coronary-coronary bypass was observed more often in cases in which the recipient coronary artery had less than 75% stenosis. CONCLUSION: OPCAB using only the LITA with a composite RA can be successfully and safely performed in patients with multivessel disease. Late postoperative follow-up of the flow competition is necessary to delineate the significance of flow competition.

Aged↗
PubMed2004

Is there a difference between diabetic and non-diabetic ITAs? Histomorphological and immunohistochemical examinations of internal thoracic arteries.

BACKGROUND: The relative resistance to arteriosclerosis of the internal thoracic artery is clinically valid. The aim of this study was to evaluate the graduation of intima and media fibrosis in ITA parts and to determine the extent of atherosclerosis using immunohistochemical methods related to patients' risk factors. METHODS: 227 distal ITA segments from 144 male and 83 female patients were examined. Mean age was 66.7 +/- 9.03 years. HE and Elastica van Gieson staining was performed to detect intima-/mediafibrosis. POPULATION: insulin-dependent diabetes mellitus (idDM; n = 35), non-insulin-dependent diabetes mellitus (nidDM; n = 32), irradiation of the chest due to cancer (n = 27), control group with isolated hyperlipidemia, hypertension, peripheral vascular disease (n = 133). 12 ITA segments of each group were examined immunohistochemically using CD34, CD68, Tenascin, Collagen III, Collagen IV. RESULTS: Histomorphological examinations using HE and Elastica van Gieson stainings showed for idDM-ITAs no fibrosis in 57 %, slight fibrosis in 34 %, medium in 6 %, no severe, for nidDM-ITAs no fibrosis in 63 %, slight 31 %, medium 3 %, severe 3 %, for ITAs after irradiation: no fibrosis in 37 %, slight in 62 %, no medium or severe fibrosis. Compared to the control group there was no statistically significant difference in diabetic ITAs. Immunohistochemical examinations, scored on a 0 - 3 basis with 0 being the lowest (no reaction), 3 the highest (severe reaction), showed mostly no or slight reaction to CD34, CD68, Tenascin, and Collagen III for intima and media, with comparable results for diabetic or "irradiated" ITAs to those of the control group. The most distinct reaction (medium= 2), was detected for Collagen IV, a marker which outlines basement membranes of endothelia and smooth muscle cells of the vessel wall, but without differences between the four groups. No severe reactions were observed. CONCLUSIONS: The relative resistance of ITA to arteriosclerosis could be demonstrated in 227 ITA segments. Immunohistochemistry supports histomorphological findings. The influence of diabetes mellitus and irradiation remains irrelevant.

Aged↗
PubMed1993

Human internal thoracic artery reactivity to dopaminergic agents.

BACKGROUND: Vasospasm of the internal thoracic artery (ITA) is common. The purpose of this study was to characterize the vascular reactivity of human ITA to dopaminergic agents used in patients undergoing coronary bypass surgery (CBS): dopamine, dobutamine, and dopexamine. METHODS AND RESULTS: Segments of the distal ITA 3 mm long were obtained from patients undergoing CBS, mounted on two stainless steel wires in a tissue bath filled with Krebs' solution at 37 degrees C, and attached to a force-displacement transducer. To assess the functional status of the endothelium, the arterial segments were preconstricted with phenylephrine 10(-5) mol/L and then exposed to increasing concentrations of acetylcholine (10(-8) to 10(-5) mol/L). To study vessel relaxation, segments were again preconstricted with phenylephrine 10(-5) mol/L and concentration-relaxation responses to dopamine, dobutamine, and dopexamine (10(-8) to 10(-4) mol/L) were obtained. There was significant vessel relaxation with both dobutamine (log EC50 = -5.83 +/- 0.16) and dopexamine (log EC50 = -5.37 +/- 0.06) but none with dopamine. Vasoconstrictor effects of the drugs were studied from baseline tension. Neither dobutamine nor dopexamine caused vasoconstriction from baseline tension, whereas vessels exposed to dopamine showed constriction at high concentrations. The vessel responses to the dopaminergic agents did not differ according to the functional status of the endothelium as initially assessed by acetylcholine-induced vessel relaxation. CONCLUSIONS: High-dose dopamine may aggravate ITA vasoconstriction, whereas dobutamine and dopexamine appear to cause vasodilation only.

Analysis of Variance↗
PubMed1992

Branches of the internal thoracic artery of rats supplying the heart, the sinus regions and the brachiocephalic veins.

Branches of the internal thoracic artery (ITA) of rats which supply the heart, the sinus regions (see Terminology 1) and the brachiocephalic veins, were macroscopically studied. Two major branches of the ITA, the pericardiacophrenic artery and the descending ramus of the bronchoesophageal artery, were found supplying branches to these central portions of the cardiovascular system (see Table 1). They constituted, together with the ordinal coronary arteries, a system of dual blood supply to the heart as reported by Grant & Regnier (1926), Halpern et al. (1953, 1954) and Hebel & Stromberg (1986). This finding also supports a proposal of Grant & Regnier (1926) that the rat ITA emits cardiac branches which should be classified on the vertebrate scale to the caudal or extracoronary artery. Branches of the ITA to the heart, the sinus regions and to the brachicephalic veins were found to be classified into 2 major groups depending on their choice of entrance--arterial portal and venous porta; the latter was further divided into 3 subgroups depending on their selection of the (lateral or pulmonary or esophageal) mesocardium for traveling to the venous porta (see Table 2).

Animals↗
PubMed1985

[Catheter embolization of the thoracic arteries in the treatment of lung hemorrhage].

In cases of acute, life-threatening pulmonary haemorrhage, immediate angiographic localisation of the source of haemorrhage is mandatory. Instead of a surgical intervention, transcatheter angiographic therapeutic embolisation may be performed. Embolisation is an effective method with only minimal complications, in favourable contrast to the 23 to 30% mortality encountered with surgical procedures. Embolisation, therefore, should be the first procedure in patients presenting with acute pulmonary haemorrhage. It must be emphasised that in cases of chronic pleuro-pulmonary diseases bleeding occurs not only from bronchial arteries. In 64% of these cases, the bleeding artery originates from a thoracic or diaphragmatic artery. The authors were able to treat 26 of 34 pulmonary haemorrhages (76%) by transcatheter embolisation. In 4 of these patients recurrent haemorrhage was treated by transcatheter embolisation. Severe complications were not noted in any case.

Adult↗
PubMed1994

Diabetes mellitus, internal thoracic artery grafting, and risk of an elevated hemidiaphragm after coronary artery bypass surgery.

The elevated hemidiaphragm after coronary artery bypass grafting (CABG) that occurs in some patients is associated with internal thoracic artery (ITA) grafting as well as with the use of topical cardiac hypothermia. An increased incidence of elevated hemidiaphragm after CABG surgery in diabetic patients was observed. To determine the incidence and risk factors of elevated hemidiaphragm after CABG surgery and the relationship to preoperative diabetes, 200 consecutive patients undergoing CABG were studied; 29 (14.5%) had hemidiaphragm elevation postoperatively (25 on the left, 1 on the right, 3 bilateral). In the remaining 171 there was no hemidiaphragm elevation. Factors analyzed were age, gender, preoperative diabetes, duration of cardiopulmonary bypass (CPB) and aortic cross-clamping, minimum esophageal temperature during CPB, and use of the ITA graft. Univariate analysis showed a significant association between elevated hemidiaphragm and diabetes (P < 0.05), left ITA grafting (P < 0.01), and age (P < 0.05). Right ITA was not used for any patient. Multivariate analysis ruled out age, whereas preoperative diabetes and the use of the ITA remained the independent factors associated with elevated hemidiaphragm (odds ratio, 3.41; 95% confidence interval 1.41 to 8.18, and 2.86; 1.01 to 8.06, respectively). The relative risk of an elevated hemidiaphragm was 9.75 in diabetic patients with the ITA graft, as compared with nondiabetic patients without this graft. All 3 patients with bilateral diaphragm paralysis and a patient with a right hemidiaphragm elevation were diabetic. In conclusion, both diabetes and use of the ITA graft appear to be important risk factors for the development of elevated hemidiaphragm following CABG.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗