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Wim N.j.c. Van Asten - One of the best experts on this subject based on the ideXlab platform.
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Noninvasive hemodynamic assessment of the Internal Mammary Artery in myocardial revascularization
The Annals of thoracic surgery, 1993Co-Authors: Jacques A.m. Van Son, Luc Noyez, Stefan H. Skotnicki, Michiel B.m. Peters, Nico H.j. Pijls, Wim N.j.c. Van AstenAbstract:Using transthoracic B-mode imaging and Doppler spectrum analysis it was found that the luminal diameter of the Internal Mammary Artery and its hemodynamics were not significantly different among 15 preoperative patients (64 +/- 10 years) who underwent myocardial revascularization using the left Internal Mammary Artery and young and older control groups (25 +/- 3 years and 61 +/- 9 years, respectively). These data indicate that older age does not significantly adversely influence the degree of intimal thickening and compliance in the Internal Mammary Artery. Doppler spectrum analysis of the Internal Mammary Artery in the patients who were operated on revealed conversion from a triphasic systolic waveform preoperatively to a unidirectional combined systolic/diastolic waveform at 1 week and 2 and 6 months postoperatively, characterized by a significant increase in the diastolic blood flow velocity and a significant decrease in the systolic blood flow velocity and the pulsatility and resistance indices. This study indicates that transthoracic B-mode imaging and Doppler spectrum analysis are promising noninvasive techniques in the preoperative assessment of Internal Mammary Artery morphology and physiology. In addition, Doppler spectrum analysis can also be used in the long-term serial assessment of the Internal Mammary Artery conduit after myocardial revascularization.
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Use of Internal Mammary Artery in myocardial revascularization after mediastinal irradiation.
The Journal of thoracic and cardiovascular surgery, 1992Co-Authors: Jacques A.m. Van Son, Luc Noyez, Wim N.j.c. Van AstenAbstract:Ten patients with radiation-associated proximal coronary Artery disease underwent myocardial revascularization. In seven patients (group A) the Internal Mammary Artery was used and in the other three (group B) only venous conduits were used. Except for mild adhesions between the pericardium and the epicardium, no unusual technical problems were encountered. In all patients in group A the Internal Mammary Artery exhibited excellent flow, and histologic examination in two patients revealed a normal intima and media with only slight fibrosis of the adventitia. In two patients in group B, fibrosis of the Internal Mammary Artery precluded its use, whereas the third patient had contraindications prohibiting use of the Internal Mammary Artery. Long-term follow-up (range 6 to 72 months) revealed that one patient in group A died late of metastatic disease, and of the remainder (nine patients), seven were in New York Heart Association class I and two were in class II. Preoperative assessment of the Internal Mammary Artery by angiography or, alternatively, B-mode imaging with Doppler spectrum analysis is recommended in patients with radiation-induced coronary Artery disease who are scheduled to undergo myocardial revascularization with intended use of the Internal Mammary Artery. In our experience, despite previous exposure to irradiation, the Internal Mammary Artery should still be considered as a viable conduit for myocardial revascularization when preoperative assessment shows patency.
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Reactive hyperemia in the nonused Internal Mammary Artery after median sternotomy
The Annals of thoracic surgery, 1992Co-Authors: Jacques A.m. Van Son, Stefan H. Skotnicki, Heino A. Folmer, Wim N.j.c. Van AstenAbstract:Doppler spectrum analysis was performed in the nonused Internal Mammary Artery in a group of patients who underwent myocardial revascularization using the contralateral Internal Mammary Artery and in both Internal Mammary arteries in a group of patients who underwent median sternotomy for cardiac surgical procedures in which the Internal Mammary Artery was not used. In all nonused Internal Mammary arteries the preoperatively triphasic systolic flow pattern had postoperatively converted into a unidirectional systolic flow pattern with a large diastolic flow component, characterized by a significant increase in the diastolic flow parameters and a significant decrease in the resistance and pulsatility indices. This effect had almost subsided at 6 months postoperatively. This study indicates that the reactive hyperemia observed in the nonused Internal Mammary Artery in the early postoperative period is mainly caused by the temporarily increased metabolic demand of the anterior thoracic wall and mediastinum, rather than by the metabolic demand of the anterior diaphragm and the contralateral rectus abdominis muscle after deprivation of their main nutritional vessel.
Jacques A.m. Van Son - One of the best experts on this subject based on the ideXlab platform.
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Noninvasive hemodynamic assessment of the Internal Mammary Artery in myocardial revascularization
The Annals of thoracic surgery, 1993Co-Authors: Jacques A.m. Van Son, Luc Noyez, Stefan H. Skotnicki, Michiel B.m. Peters, Nico H.j. Pijls, Wim N.j.c. Van AstenAbstract:Using transthoracic B-mode imaging and Doppler spectrum analysis it was found that the luminal diameter of the Internal Mammary Artery and its hemodynamics were not significantly different among 15 preoperative patients (64 +/- 10 years) who underwent myocardial revascularization using the left Internal Mammary Artery and young and older control groups (25 +/- 3 years and 61 +/- 9 years, respectively). These data indicate that older age does not significantly adversely influence the degree of intimal thickening and compliance in the Internal Mammary Artery. Doppler spectrum analysis of the Internal Mammary Artery in the patients who were operated on revealed conversion from a triphasic systolic waveform preoperatively to a unidirectional combined systolic/diastolic waveform at 1 week and 2 and 6 months postoperatively, characterized by a significant increase in the diastolic blood flow velocity and a significant decrease in the systolic blood flow velocity and the pulsatility and resistance indices. This study indicates that transthoracic B-mode imaging and Doppler spectrum analysis are promising noninvasive techniques in the preoperative assessment of Internal Mammary Artery morphology and physiology. In addition, Doppler spectrum analysis can also be used in the long-term serial assessment of the Internal Mammary Artery conduit after myocardial revascularization.
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Use of Internal Mammary Artery in myocardial revascularization after mediastinal irradiation.
The Journal of thoracic and cardiovascular surgery, 1992Co-Authors: Jacques A.m. Van Son, Luc Noyez, Wim N.j.c. Van AstenAbstract:Ten patients with radiation-associated proximal coronary Artery disease underwent myocardial revascularization. In seven patients (group A) the Internal Mammary Artery was used and in the other three (group B) only venous conduits were used. Except for mild adhesions between the pericardium and the epicardium, no unusual technical problems were encountered. In all patients in group A the Internal Mammary Artery exhibited excellent flow, and histologic examination in two patients revealed a normal intima and media with only slight fibrosis of the adventitia. In two patients in group B, fibrosis of the Internal Mammary Artery precluded its use, whereas the third patient had contraindications prohibiting use of the Internal Mammary Artery. Long-term follow-up (range 6 to 72 months) revealed that one patient in group A died late of metastatic disease, and of the remainder (nine patients), seven were in New York Heart Association class I and two were in class II. Preoperative assessment of the Internal Mammary Artery by angiography or, alternatively, B-mode imaging with Doppler spectrum analysis is recommended in patients with radiation-induced coronary Artery disease who are scheduled to undergo myocardial revascularization with intended use of the Internal Mammary Artery. In our experience, despite previous exposure to irradiation, the Internal Mammary Artery should still be considered as a viable conduit for myocardial revascularization when preoperative assessment shows patency.
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Reactive hyperemia in the nonused Internal Mammary Artery after median sternotomy
The Annals of thoracic surgery, 1992Co-Authors: Jacques A.m. Van Son, Stefan H. Skotnicki, Heino A. Folmer, Wim N.j.c. Van AstenAbstract:Doppler spectrum analysis was performed in the nonused Internal Mammary Artery in a group of patients who underwent myocardial revascularization using the contralateral Internal Mammary Artery and in both Internal Mammary arteries in a group of patients who underwent median sternotomy for cardiac surgical procedures in which the Internal Mammary Artery was not used. In all nonused Internal Mammary arteries the preoperatively triphasic systolic flow pattern had postoperatively converted into a unidirectional systolic flow pattern with a large diastolic flow component, characterized by a significant increase in the diastolic flow parameters and a significant decrease in the resistance and pulsatility indices. This effect had almost subsided at 6 months postoperatively. This study indicates that the reactive hyperemia observed in the nonused Internal Mammary Artery in the early postoperative period is mainly caused by the temporarily increased metabolic demand of the anterior thoracic wall and mediastinum, rather than by the metabolic demand of the anterior diaphragm and the contralateral rectus abdominis muscle after deprivation of their main nutritional vessel.
Michael J Mack - One of the best experts on this subject based on the ideXlab platform.
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risk factors for operative mortality and sternal wound infection in bilateral Internal Mammary Artery grafting
The Journal of Thoracic and Cardiovascular Surgery, 1994Co-Authors: William H Ryan, Tea E Acuff, Richard T Bowman, Mark B Douthit, Chengqin Yang, Michael J MackAbstract:Abstract To investigate risk factors for operative mortality and sternal infection in patients undergoing bilateral Internal Mammary Artery grafting, we analyzed the data of 199 patients who underwent this procedure from January 1986 through June 1992. These patients were also compared with those who underwent only saphenous vein grafting (1664 cases) and those who underwent unilateral Internal Mammary Artery grafting (3359 cases) during the same time frame. The operative mortality was 3.52% (7/199) in the patients having bilateral Internal Mammary Artery grafting, 2.71% (91/3359) in those having unilat eral Internal Mammary Artery grafting, and 8.53% (142/1664) in the patients having saphenous vein grafting ( p 70 years) ( p 70 years) patients and for emergency operation. Obese patients have a high risk for sternal infection after bilateral Internal Mammary Artery grafting. (J T HORAC C ARDIOVASC S URG 1994;107:196-202)
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Middle and proximal sections of the human Internal Mammary Artery are not "passive conduits".
The Journal of thoracic and cardiovascular surgery, 1994Co-Authors: Tea E Acuff, William H Ryan, Chengqin Yang, Michael J MackAbstract:Abstract Recent studies have shown that blood flow through the Internal Mammary Artery graft is inadequate for maximal exercise and that hypoperfusion may be worsened by high-dose vasopressor therapy that could further reduce arterial graft flow. Histologic studies have suggested that the human Internal Mammary Artery is an elastic "passive conduit" along the majority of its length. However, although the pharmacologic reactivity at the distal section of the Internal Mammary Artery has been extensively studied, this evaluation has never been done at the middle and proximal sections. It is extremely important to understand the contractility at the midsection of the Internal Mammary Artery because, in a critical situation, any contraction may further reduce the Internal Mammary Artery flow. The present study was designed to investigate the following: (1) Is it true that the pharmacologic reactivity of the human Internal Mammary Artery is different among various sections? and (2) Is the human Internal Mammary Artery a nonreactive "passive conduit" at its most important area used as the graft—the middle and the proximal sections? One hundred six human Internal Mammary Artery ring segments taken from patients who underwent Internal Mammary Artery grafting procedures (29 from the proximal, 38 from the middle, and 39 from the distal sections) were studied in the organ bath under a physiologic pressure. Concentration-response curves were established for norepinephrine, endothelin-1, U46619, potassium, and glyceryl trinitrate (precontracted with 10 nmol/L U46619). Contraction forces were standardized (in grams per millimeter circumference) at a pressure of 100 mm Hg. The contraction force was greater in the distal section than in other sections for norepinephrine ( p = 0.002) and endothelin-1 ( p = 0.04). No differences were seen for potassium, U46619, or glyceryl trinitrate, whereas the effective concentration inducing 50% of maximal response for U46619 was 100-fold lower in the distal than in the middle section (9.06 ± 0.34 versus 7.06 ± 0.48 -log M; p = 0.01) indicating higher sensitivity in the distal section. This study for the first time shows various reactivity along the full length of the human Internal Mammary Artery and shows that the distal section is the most reactive part of the graft. However, although the middle and the proximal sections are less reactive to some vasoconstrictors (norepinephrine and endothelin-1), it is not a "passive conduit" and it contracts with all four vasoconstrictors tested. The contractility at the midsection should be fully appreciated because, under critical postoperative situations (hypoperfusion) or during exercise with marginal flow, the ability of these sections to contract in response to vasoconstrictors may become clinically detrimental and require pharmacologic therapy. (J THORAC CARDIOVASC SURG 1994;108:741-6)
Luc Noyez - One of the best experts on this subject based on the ideXlab platform.
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Recycling of the Internal Mammary Artery in coronary reoperation
The Annals of thoracic surgery, 1993Co-Authors: Luc Noyez, Leon K. LacquetAbstract:In 5 patients undergoing a coronary Artery reoperation, the Internal Mammary Artery graft was taken down and reused. No special problems were encountered perioperatively or postoperatively. Because the number of grafts and distal anastomoses performed in coronary reoperations is increasing, lack of suitable graft conduits will be a problem in the future. Recycling an Internal Mammary Artery graft may be an option to achieve good revascularization in some coronary reoperations.
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Noninvasive hemodynamic assessment of the Internal Mammary Artery in myocardial revascularization
The Annals of thoracic surgery, 1993Co-Authors: Jacques A.m. Van Son, Luc Noyez, Stefan H. Skotnicki, Michiel B.m. Peters, Nico H.j. Pijls, Wim N.j.c. Van AstenAbstract:Using transthoracic B-mode imaging and Doppler spectrum analysis it was found that the luminal diameter of the Internal Mammary Artery and its hemodynamics were not significantly different among 15 preoperative patients (64 +/- 10 years) who underwent myocardial revascularization using the left Internal Mammary Artery and young and older control groups (25 +/- 3 years and 61 +/- 9 years, respectively). These data indicate that older age does not significantly adversely influence the degree of intimal thickening and compliance in the Internal Mammary Artery. Doppler spectrum analysis of the Internal Mammary Artery in the patients who were operated on revealed conversion from a triphasic systolic waveform preoperatively to a unidirectional combined systolic/diastolic waveform at 1 week and 2 and 6 months postoperatively, characterized by a significant increase in the diastolic blood flow velocity and a significant decrease in the systolic blood flow velocity and the pulsatility and resistance indices. This study indicates that transthoracic B-mode imaging and Doppler spectrum analysis are promising noninvasive techniques in the preoperative assessment of Internal Mammary Artery morphology and physiology. In addition, Doppler spectrum analysis can also be used in the long-term serial assessment of the Internal Mammary Artery conduit after myocardial revascularization.
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Use of Internal Mammary Artery in myocardial revascularization after mediastinal irradiation.
The Journal of thoracic and cardiovascular surgery, 1992Co-Authors: Jacques A.m. Van Son, Luc Noyez, Wim N.j.c. Van AstenAbstract:Ten patients with radiation-associated proximal coronary Artery disease underwent myocardial revascularization. In seven patients (group A) the Internal Mammary Artery was used and in the other three (group B) only venous conduits were used. Except for mild adhesions between the pericardium and the epicardium, no unusual technical problems were encountered. In all patients in group A the Internal Mammary Artery exhibited excellent flow, and histologic examination in two patients revealed a normal intima and media with only slight fibrosis of the adventitia. In two patients in group B, fibrosis of the Internal Mammary Artery precluded its use, whereas the third patient had contraindications prohibiting use of the Internal Mammary Artery. Long-term follow-up (range 6 to 72 months) revealed that one patient in group A died late of metastatic disease, and of the remainder (nine patients), seven were in New York Heart Association class I and two were in class II. Preoperative assessment of the Internal Mammary Artery by angiography or, alternatively, B-mode imaging with Doppler spectrum analysis is recommended in patients with radiation-induced coronary Artery disease who are scheduled to undergo myocardial revascularization with intended use of the Internal Mammary Artery. In our experience, despite previous exposure to irradiation, the Internal Mammary Artery should still be considered as a viable conduit for myocardial revascularization when preoperative assessment shows patency.
Frank C. Spencer - One of the best experts on this subject based on the ideXlab platform.
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Sternal wound infections and use of Internal Mammary Artery grafts.
The Journal of thoracic and cardiovascular surgery, 1991Co-Authors: Eugene A. Grossi, Rick A. Esposito, Gregory A. Crooke, Aubrey C. Galloway, Alfred T. Culliford, Kathy Yao, Frank C. SpencerAbstract:Previous studies have provided conflicting evidence as to whether an increased risk of mediastinitis is associated with use of the Internal Mammary Artery as a coronary bypass graft. In this study the effects of Internal Mammary Artery grafts on wound complications were analyzed in a prospective, nonrandomized fashion. At New York University Medical Center from January 1985 through May 1988, 2356 patients underwent isolated coronary revascularization. Among these patients 1394 received one or more Internal Mammary Artery grafts (group I) and 962 had vein grafts only (group II). Group I had a mean age of 59.5 years versus 67.7 years in group II; diabetes was equally present in both groups (22.7% versus 24.7%). Operative mortality rate was 1.3% in group I and 5.6% in group II. Sternal infection was significantly more prevalent in group I (2.2%, 31/1394) than in group II (0.8%, 8/962). Multivariate analysis revealed that aortic crossclamp time, use of a single Internal Mammary Artery graft, use of a double Mammary graft, and diabetes were associated with increased risk of sternal infection. The use of bilateral Internal Mammary Artery grafting doubled the odds ratio of the risk compared with use of a single Mammary graft, and the combination of diabetes and double Internal Mammary Artery grafts increased the odds ratio 13.9-fold. Patients with an Internal Mammary Artery graft who had sternal infection had a longer period of hospitalization than patients without a Mammary Artery graft who had sternal infection. We conclude that the risk of sternal infection is increased by the use of an Internal Mammary Artery graft, especially use of double Mammary grafts in the presence of diabetes.