Search

OBJECTIVE There is varying evidence on the role of skeletonization of internal mammary artery in reducing the risk of sternal wound infections and ischemia following bilateral internal mammary artery grafting. Post-operative clinical outcomes of skeletonized bilateral internal mammary artery versus pedicled bilateral internal mammary artery harvesting in patients undergoing coronary artery bypass surgery were compared. METHODS A comprehensive electronic search was conducted using MEDLINE, Scopus, EMBASE, Cochrane database and Google Scholar from inception until 15 June 2020. All studies directly comparing skeletonized and pedicled bilateral internal mammary artery harvesting were included. Meta-analysis and trial sequential analysis were conducted. RESULTS Nine studies (one randomized controlled trial and eight observational studies) consisting of 3649 patients (2050 patients with skeletonized bilateral internal mammary artery grafting and 1599 patients with pedicled bilateral internal mammary artery grafting) were included. Pooled effects analysis and trial sequential analysis reported significantly lower risk of sternal wound infection with skeletonized bilateral internal mammary artery harvesting (OR 0.27, 95% CI 0.20-0.51, p

There are multiple treatment strategies and flap options to cover defects after deep sternal wound infections and other similar sternal defects. The choice of flap is made according to surgeons' preferences and the size and location of the defect. Our aim is to introduce a new option to cover these kinds of defects with an internal mammary artery perforator flap combined with a pectoralis major muscle flap mostly raised with a muscle-sparing technique.We treated 13 patients with a sternal defect after cardiothoracic operations with this technique between 2010-2016. Ten patients had a deep sternal wound infection, two had an infection of the prosthesis after carotico-subclavian bypass and one had a fragmented sternum. Nine patients were treated with an internal mammary artery perforator fasciocutaneous flap with a muscle-sparing pectoralis major muscle flap and four patients with an internal mammary artery perforator fasciocutaneous flap combined with a right pectoralis major muscle flap.Three patients (23%) experienced major complications and four patients (31%) had conservatively treated minor complications. There were no flap losses.This combination of flaps is a suitable option for patients with large defects in whom direct skin closure is not possible. It can be utilized for defects comprising the entire vertical length of the sternum. These are local flaps with a short operation time and are therefore most suitable for patients with comorbidities in whom major surgery is not an option.

Atherosclerosis of the internal mammary artery (IMA) is generally regarded as a rare (but existent) pathological entity with only a few cases reported in the most recent literature. The only study which to our knowledge has investigated the ultrastructural features of IMA atherosclerosis, demonstrate the presence of endothelial cells loss, defects of internal elastic lamina with no evidence of lipid accumulation. In the present study, we describe two cases of IMA atherosclerosis in which ultrastructural analysis revealed the presence of a typical atherosclerotic plaque morphology with infiltration of inflammatory cells, formation of intraplaque lipid pools, and accumulation of lipid-laden foam cells throughout the thickened intima, never described in this rare lesion before. Microscopically, the lesions were also characterized by intimal thickening, invagination of endothelial cells, migration of smooth muscle cells with splitting, fenestration and/or fragmentation of the elastic sheets. Our observations add new data to the scarce and contradictory literature and to this largely understudied vascular disorder.

We used internal mammary artery perforator (IMAP) flaps from the opposite side for reconstruction of small-to-medium-sized defects in the chest wall. The IMAP flaps were used in two patients who had unhealed, localised ulcers of the chest wall with exposure of the ribs after radical mastectomy. The lesion was excised widely, and the flap, based on a perforator vessel in the second or third intercostal space of the opposite chest wall, was raised. The flap was rotated from 90° to 180° along the vascular axis to the chest wall defect. The donor site was closed primarily. Both flaps showed stable postoperative circulation and survived completely. Defects of the chest wall could be covered with healthy, well-vascularised tissue on one perforator without deep infection. The IMAP flap is a reliable and less invasive option to be considered for medial, localised, reconstruction of the chest wall.

In 18 patients the inferior epigastric artery (IEA) was used for myocardial revascularization along with the left internal mammary artery and saphenous vein (4.5 grafts/patient). Preoperative duplex scan assessment of IEA correctly predicted its distal diameter. At operation the mean internal diameter was 1.6 (1.5-2.0) mm distally and 2.1 (2.0-2.5) mm proximally. The mean in situ flow after intraluminal injection of papaverine was 115 (36-210) ml/min in IEA and 136 (56-210) ml/min in internal mammary artery. There was no perioperative death or myocardial infarction. Morbidity associated with IEA harvesting was minor: ultrasonography showed diastasis and slower contraction of the rectus muscle at the harvesting site than contralaterally in one case. The preoperative duplex scan was useful for evaluating IEA size. All the patients were clinically improved. The patency rate at selective IEA angiography 3 months post-operatively was 72% (13/18). This poor early patency of IEA in our small series raises doubts concerning the vessel's suitability for myocardial revascularization.

Resection of the internal shelf through a longitudinal aortotomy and widening with the free end of the left in situ internal mammary artery (IMA) were steps in correction of aortic coarctation with isthmus hypoplasia in nine patients aged 9-14 (mean 10.5) years. Electromagnetic flowmetry was performed on the left IMA before and after the repair. The essential finding was considerably increased mean blood flow in the IMA flap during cross-clamping proximal to the completed repair, from 53 +/- 48 to 430 +/- 74 ml/min (378 +/- 78%). The IMA thus is a powerful conduit with extraordinary flow capacity when runoff is appropriate. Integration of IMA as a viable flap in the repair of aortic coarctation implies that this artery increases its collateral flow contribution to the distal aorta.

The incidence of atherosclerosis in internal mammary, subclavian, carotid and coronary arteries was studied in an autopsy series of 153 patients, and the structure of the internal elastic lamina was compared in internal mammary and radial arteries. Atherosclerotic changes were exceptional in internal mammary artery, whereas only 12–30% of the other arteries were inacroscopically normal. The internal elastic lamina of internal mammary artery was found to be significantly less fragmented than that of radial artery, which may partly explain both the lower incidence of atherosclerosis in internal mammary artery and failure of radial artery grafts. As six (3.9%) of the 153 patients had total or almost total subclavian artery occlusion, subclavian angiography is recommended for patients who are candidates for coronary bypass grafting with internal mammary artery.

Spontaneous coronary artery dissection is an uncommon clinical entity, its presentation and management similar to atherosclerotic coronary artery disease. We report on a young adult male who presented with myocardial infarction due to simultaneous dissection of left anterior descending and right coronary artery. He was treated with bilateral interal mammary artery grafts.

We successfully reconstructed a large defect that had been created by resection of an unstable, contracted, and hypertrophic scar with a chronic ulcer on the lower sternal area of a 67-year-old man. We used bilateral V-Y advancement flaps based on internal mammary artery perforators.

In 28 patients with the left internal mammary artery (IMA) used as a sequential coronary artery graft, clinical and angiographic evaluation was made 19-47 months postoperatively. Patency was 96% in the proximal anastomoses and 93% in all the anastomoses. Angiography, however, showed optimal function in only 75% of the distal graft ends. These observations indicate that routine use of left IMA as a sequential graft should be restricted to experienced surgeons. Clinical and angiographic findings did not always correlate, emphasizing that evaluation of IMA-graft patency should include angiography.

Coronary atherosclerosis is discussed from the standpoint of natural history and survival. The operative treatment for ischemic heart disease is reviewed beginning with the advent of the venous autograft to the most recent advance, the internal mammary artery graft. Comparative survival between medical and surgical modes of treatment are described as well as factors in the revascularization selection process that directly influence longevity. During the last 6 years, experience in selection and a steady improvement in technical proficiency have brought about a decline in operative mortality and morbidity, thus yielding further improvement in postoperative long-term survival.

Coronary artery reoperation was performed on 101 patients between 1972 and 1985. The resternotomy was associated with major hemorrhage in 12 cases. Of 29 patent internal mammary artery (IMA) grafts, 11 (38%) were damaged during mobilization of the left ventricle. At reoperations performed more than a year after the initial operation, increased graft blood flow compared with the first operation was observed in IMA but not in vein grafts. There were six early deaths (6%). The 5-year survival rate, inclusive of early mortality, was 90%. After a median of 2.5 years, 82% of the patients reported symptomatic improvement and 22% were completely free from angina, but full physical fitness was restored in only 3%. Excluding the patients of retirement age, 35% were able to resume work after the reoperation. Coronary artery reoperation should be considered only for patients with severe angina, because of the increased surgical risk and the lower likelihood of completely relieved symptoms. Presence of a patent IMA graft necessitates special caution.

A technique for correction of aortic coarctation is described in which the left internal mammary artery (IMA) is distally divided for integration in the repair. After resection of the internal coarctation ridge, the distal end of the freed IMA is obliquely severed, opened to required length and thus fashioned as a widening flap suitable fro aortoplasty. IMA free end flap aortoplasty gave promising early results in seven patients aged 10-15 years with aortic coarctation and IMA of good quality and calibre.

Coronary angiography was performed two weeks after coronary bypass surgery on 112/121 consecutive operative survivors (93%), on 97/119 one-year survivors (82%) and on 79/108 five-year survivors (73%). Occlusions of the grafts were uncommon after the first year. The cumulative five-year patency, calculated with the actuarial method, was 89% for internal mammary artery (IMA) grafts and 77% for aortocoronary saphenous vein (SV) grafts. Almost 70% of the SV grafts exhibited a 15-50% reduced diameter after one year and 10% showed progressive narrowing at five years. Diffuse luminal narrowing did not predict graft failure. The incidence of localized narrowings present at two weeks after surgery was, however, significantly higher among SV grafts, which occluded within one year, than among those patent after five years. In 5% of the IMA grafts the diameter was reduced 15-80% after five years. This was related either to obstruction at the anastomotic site or to low-grade proximal coronary stenosis. No less than 12% of the IMA grafts increased 20-50% in diameter as an adaptation to good distal runoff.

A review of 2,902 coronary artery bypass grafting operations is presented. During the 16-year study period the mean patient age rose from 51 to 59 years and the average number of grafts per patient from 1.5 to 3.0. There were 81 early deaths (2.8%, the most common cause being myocardial infarction (68%). Left main stem stenosis was present in 23 of these 81 patients and depressed left ventricular function in 30. Compared with the survivors, the deceased patients were characterized by higher age, proportionately large numbers of women, combined procedures and reoperations and less use of internal mammary artery grafts. Of the 94 patients aged greater than or equal to 70, 11 died (12%). The perioperative mortality was significantly greater (p less than 0.05) in women than in men (20/457 vs. 61/2445 viz. 4.4% vs. 2.5%). Combined operations were associated with 8.7% (27/311), reoperations with 6% (6/101) and coronary endarterectomy with 5% (4/75) early deaths. In the last year of the study there were three early deaths among 359 patients (0.8%) who underwent primary isolated coronary bypass grafting without endarterectomy. The perioperative risks fell steadily during 16 years, despite rising proportions of older patients, combined procedures, reoperation and coronary endarterectomy.

SummaryMyocardic revascularization was attempted using a wide variety of methods. In fact, most of those methods act by enlarging the normally existing intercoronary anastomosis, this as a result of a mechanical irritation of the heart surface.Such a result can be easily obtained by a minor operation, i.e. the introduction of talcum powder into the pericardium.The ligation of the mammary arteries is an equally minor operation, which may be performed even on poor risk patients. Its effectiveness is far from being demonstrated experimentally, whereas clinical records seem to be more promising. Further attempts should therefore be justified.

The angiographic and histological findings at myocardial vascularization were studied in dogs, where an internal mammary artery implantation had been performed either acutely or three or six weeks earlier. The findings were related to the myocardial blood supply from the implants, studied with Kr85 clearance technique during temporary occlusions of the cognate coronary artery. The study failed to demonstrate filling of the intramural section of the implants at in vivo angiography immediately after implantation, which was shown under artificial conditions. Neither the histological findings nor the measurements of myocardial capillary blood flow did support the view of significant function immediately after the implantation. Three weeks later, however, anastomoses between the implants and the coronary arteries were seen, associated with a significant increase of nutritive blood flow in the myocardium. The blood flow from the six weeks implants was almost double that from the three weeks and in both series t...

The left internal mammary artery was implanted into the myocardium in 16 dogs. In 8 dogs all major branches of the implant artery were ligated to create a “closed” implant. In the other 8 dogs 3 major branches were left open in the myocardial tunnel, i.e. “open” implants. Blood flow in the implant artery trunk was measured with an electromagnetic flowmeter. The flow value obtained during acute occlusion of the cognate coronary artery was used. Myocardial tissue blood flow in the implantation area was measured by recording the clearance rate of 133Xenon after local intramyocardial injections and during occlusion of the coronary artery. The flow value during occlusion of the implant artery was subtracted from the value with the unclamped artery. The “ischaemic” area was weighed, and the relative flow values were converted to absolute values by multiplying them with this weight. There was a close agreement between the flows obtained with the two methods, (r = 0.86). This indicates that most of the implant fl...