Left Internal Mammary Graft Research Articles

An Interesting Case: Retrograde Blood Flow from a LIMA Sustaining Hemodialysis via an AVF

A case is described in which the inflow of a left radiocephalic arteriovenous fistula was being maintained by retrograde flow from a patent left internal mammary artery bypass graft, distal to a severe left subclavian artery stenosis. The clinical manifestations of this phenomenon were angina, lateral chest wall pain during dialysis, and distal hypoperfusion of the left hand. After stenting of the subclavian lesion, all symptoms resolved.

Poor Left Ventricular Function Is Not a Contraindication for Robotic Totally Endoscopic Coronary Artery Bypass Grafting

Robotic technology has enabled performance of totally endoscopic coronary artery bypass grafting (TECABG). Published series on TECABG were primarily performed in low-risk patients, and little is known about the outcome after totally endoscopic coronary surgery in patients with severely impaired left ventricular function. We report successful endoscopic placement of a left internal mammary artery bypass graft to the left anterior descending artery using the daVinci robotic system in a patient with a severely reduced left ventricular ejection fraction.

Coronary Steal Syndrome After Coronary Artery Bypass for Anomalous Aortic Origin of a Coronary Artery

Anomalous aortic origin of a coronary artery found in a symptomatic 9-year-old boy was initially treated with coronary artery bypass grafting using a left internal mammary artery anastomoses to the left anterior descending coronary artery, but resulted in coronary ischemia, likely from a steal phenomenon. Subsequent transection of the proximal left internal mammary artery with anastomosis to the ascending aorta, and coronary ostial enlargement, resulted in a durable treatment. We recommend caution in choosing coronary artery bypass grafting using a left internal mammary artery pedicle graft for the treatment of anomalous aortic origin of a coronary artery.

Encasement of the Left Internal Mammary Arterial Graft to the Left Coronary Artery by Adenosquamous Carcinoma, an Unusual Tumor

We report a case of a patient with a previous coronary artery bypass graft who presented with chest pain and was found to have adenosquamous carcinoma encasing the left internal mammary graft to left anterior descending artery - the only viable vessel to his coronary circulation. Adenosquamous carcinoma, a rare lung cancer with a poor prognosis, causing obstruction of a bypass graft has not been previously reported.

Coronary-Subclavian Steal Syndrome Presenting with Ventricular Tachycardia

Coronary-subclavian steal through the left internal mammary graft is a rare cause of myocardial ischemia in patients who have had a coronary bypass surgery. We report a 70-year-old man who presented with sustained monomorphic ventricular tachycardia 5 years after the surgical creation of a left internal mammary to the left anterior descending artery. Cardiac catheterization illustrated that the left subclavian artery was occluded proximally and that the distal course was visualized by retrograde filling through the left internal mammary graft. Clinical ventricular tachycardia was reproducibly induced with a single ventricular extrastimulus, and antitachycardia pacing terminated the tachycardia. Restoration of blood flow by way of a Dacron graft placed between the descending aorta and the subclavian artery resulted in the total relief of symptoms. Ventricular tachycardia could not be induced during the control electrophysiologic study after surgical revascularization.

Severe coronary vasospasm in the catheterization laboratory

In 2005, a 50-year-old woman with a history of migraines, hypertension and type 2 diabetes underwent three-vessel coronary artery bypass graft surgery for symptomatic ischemic heart disease. In 2006, she had two percutaneous coronary interventions for severe stenotic lesions immediately distal to the site of the graft anastomosis in both her left anterior descending artery and her ramus branch (Figure 1A). Four months later, she was admitted to the hospital for recurrent chest pain. Her cardiac enzymes were normal. Her electrocardiogram was unchanged from a previous one, which showed anterolateral ST and T wave abnormalities consistent with myocardial ischemia. Selective coronary angiography showed diffuse, severe coronary artery vasospasm involving both her native vessels (Figure 1A) as well as the right and left internal mammary artery bypass grafts (Figure 1B). Following 200 μg of intracoronary nitroglycerin administration, the vasospasm resolved and revealed patent native and graft anatomy (Figure 1B). She was subsequently treated for variant (Prinzmetal’s) angina with a combination of oral nifedipine, diltiazem and nitrates. Figure 1) A Left coronary angiogram before intracoronary nitroglycerin, showing diffuse, severe native coronary artery vasospasm with a coronary stent visualized in the intermediate branch (arrowhead). Note the absence of graft anatomy. B Left coronary angiogram ... Variant angina is an infrequent cause of myocardial ischemia, but should always be considered in the differential diagnosis of chest pain in the context of younger patients and a history of vasospastic disorders. In the present case, coronary revascularization could have been avoided if this diagnosis was considered at the time of the initial cardiac investigations.

Current State of Integrated “Hybrid” Coronary Revascularization

The long-term benefits of a left internal mammary artery bypass graft to the left anterior descending artery (LAD) have been well described. As the patient population with multivessel coronary artery disease has grown older with greater comorbidities, less invasive approaches to revascularization have been explored. The use of drug-eluting stents has minimized the morbidity of revascularization but has failed to match the durability of coronary artery bypass grafting (CABG). Hybrid coronary revascularization (HCR) is the planned use of minimally invasive surgical techniques for left internal mammary artery-LAD grafting and the use of percutaneous coronary interventions (PCI) for non-LAD target revascularization. The optimal timing and order of revascularization in HCR remains unclear. Novel operating suites with surgical and fluoroscopic capabilities have begun to support the performance of simultaneous minimally invasive CABG and PCI. The role of HCR compared to both PCI and conventional CABG awaits the results of ongoing randomized clinical trials.

Intractable LIMA Spasm in the Postoperative Period Treated by Placement of ‘Bridging’ Stent

A woman with critical left main stenosis suffered intractable left internal mammary artery spasm post-coronary artery bypass grafting. This was managed with a left main stent and the patient stabilized. A 3-month follow-up angiogram showed a patent graft and a blocked stent.

Unicuspid aortic valve: an interesting presentation

A 52-year-old male presented with acute onset chest pain and ST-segment elevation myocardial infarction (Panel A). An urgent cardiac catheterization was performed which showed a filling defect in the left anterior descending (LAD) artery (Panel B). After failure at attempts to reperfuse the LAD, the patient underwent emergent cardiopulmonary bypass surgery with a left internal mammary graft to LAD. He was found …

Cardiac Resynchronization by Restoration of Native Ventricular Activation

A 56-year-old woman was transferred to our institution for evaluation of New York Heart Association class IV congestive heart failure that was refractory despite treatment with furosemide, carvedilol, digitalis, spironolactone, and valsartan. She was bedridden before her transfer and was referred for consideration of cardiac transplantation. Prior treatment at another institution included bypass of the left anterior descending coronary artery, a left internal mammary graft for unstable angina, and implantation of a dual-chamber cardioverter/defibrillator for ventricular tachycardia. The device was programmed for DDDR pacing, with rate limits of 80 to 130 bpm and an atrioventricular (AV) delay of 160 ms. In this setting, the patient had been paced in the right ventricle 100% of the time for 6 months before she presented at our institution. Deterioration of her condition began after cardioverter/defibrillator placement and persisted despite increasing pharmacotherapy. At the time of hospital admission, she was in florid congestive heart failure and had hypotension, elevated jugular venous pressure, bilateral lung crepitations, a murmur of mitral regurgitation, and pitting edema of the lower extremities. The initial ECG (at hospital admission) showed AV sequential pacing at 80 bpm …

Hospital Outcome Analysis After Different Techniques of Left Internal Mammary Grafts Harvesting

Although accepted worldwide as the first-choice conduit for myocardial revascularization (coronary artery bypass graft surgery), it is still questionable if left internal mammary arteries (LIMAs) do better as pedicled or skeletonized grafts. Recent reports have suggested that the skeletonized technique improves the outcomes. In all, 516 consecutive isolated coronary artery bypass graft surgery patients admitted between January 2003 and February 2007 were grouped according to the harvesting technique of LIMAs (387 pedicled versus 129 skeletonized). Intraoperative transit time flow results, hospital outcome, perioperative troponin I leakage, and echocardiographic results were analyzed. Maximum, mean, and minimum flows, pulsatility index, and graft flow reserve were stratified according to the type of surgery (on pump and off pump) and subgroups at risk (severe left ventricular hypertrophy). The transit time flow results were unsatisfactory in 4 patients (0.8%), all 4 of whom underwent redo anastomosis. Maximum, mean, and minimum flows and pulsatility index values were comparable between skeletonized and pedicled LIMAs (p = not significant), for both on-pump and off-pump surgeries (p = not significant). Graft flow reserve was comparable between the two groups (p = not significant), as well as transit time flow results in severe ventricular hypertrophy. Troponin leakage, postoperative echocardiographic recovery, and hospital outcome were comparable between the two groups (p = not significant at all time points). Only superficial wound complications proved higher in the pedicled group (2.6% versus skeletonized group: 0%; p = 0.05). Pedicled LIMA carries a higher risk for minor wound complications. Neverthless, the two techniques showed similar in-vivo functional behavior and hospital outcome. Therefore, there is no reason to prefer one technique over the other.

Simultaneous Hybrid COronary Revascularization Using Totally Endoscopic Left Internal Mammary Artery Bypass Grafting and Placement of RapamycIN Eluting Stents in the SAme IntervenTIONal Session

Objectives: Hybrid coronary revascularization procedures apply minimally invasive coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for treatment of multivessel coronary artery disease. For logistic reasons simultaneous procedures would be desirable. In a pilot study the feasibility of simultaneous robotic totally endoscopic CABG and PCI using drug eluting stents was assessed. Patients and Methods: Five patients were scheduled to undergo simultaneous combined coronary inter- vention. A left internal mammary artery bypass graft was placed to the left anterior descending artery (LAD) in a completely endoscopic fashion using the daVinci^TM telemanipulation system. PCI was carried out in the surgical operating room with the GE OEC9800 mobile coronary angiography C-arm. Rapamycin coated Cypher™ stents were placed into stenotic non-LAD targets. Results: The procedure was feasible in 4 patients, one patient was converted to a double CABG operation. There were no significant postoperative clinical complications and patients were discharged from intensive care unit and the hospital after 19 (18–61) hours and 6 (5–7) days respectively. At 6 months postoperatively all patients are free from angina. Conclusion: We conclude that simultaneous robotic totally endoscopic left internal mammary artery to LAD placement and PCI to non-LAD targets using drug eluting stents is feasible in one session.

Radial Artery Bypass Grafts Have an Increased Occurrence of Angiographically Severe Stenosis and Occlusion Compared With Left Internal Mammary Arteries and Saphenous Vein Grafts

Radial Artery Bypass Grafts Have an Increased Occurrence of Angiographically Severe Stenosis and Occlusion Compared With Left Internal Mammary Arteries and Saphenous Vein Grafts

Surgical Repair of a Left Subclavian Artery Aneurysm Causing Stenosis of a Left Internal Mammary Graft A Case Report

Subclavian artery aneurysms are extremely rare, accounting for approximately 0.1% of peripheral artery aneurysms. We present a case of a proximal left subclavian arterial aneurysm in a patient status post previous coronary artery bypass grafting; the aneurysm was complicated by involvement of the left internal mammary artery that had been previously utilized to revascularize the left anterior descending artery. Ostial stenosis of the internal mammary artery secondary to the aneurysm was present. Simultaneous reoperative coronary bypass surgery and repair of the left subclavian aneurysm was performed, with a good result. This is the second case reported in the literature of concomitant subclavian artery aneurysm repair and coronary revascularization.

Directional coronary atherectomy plus stent implantation vs. left internal mammary artery bypass grafting for isolated proximal stenosis of the left anterior descending coronary artery

The aim of this study was to compare the short- (< 30 days) and long-term (> or = 30 days) clinical outcomes of left internal mammary artery bypass grafting (LIMA-LAD) and directional coronary atherectomy plus stent implantation (DCA + stent) in the treatment of isolated proximal left anterior descending coronary (LAD) lesions. One hundred and twenty-six patients underwent LIMA-LAD and 132 consecutive patients underwent DCA + stenting. The primary endpoint was the incidence of short- and long-term major adverse cardiac events (MACE); the secondary endpoints included any periprocedural events and long-term target vessel revascularization (TVR). We found no significant between-treatment difference in the occurrence of short-term MACE, and the long-term MACE rate per 100 person-years was 3.0 in the LIMA-LAD group and 4.6 in the DCA + stent group. After 5-year follow-up, 79% of the patients in the DCA + stent group and 89% of those in the LIMA-LAD group were still MACE-free. The risk of any periprocedural events was six times lower in the DCA + stent group, and the risk of TVR was six times higher. We conclude that both procedures lead to good short- and long-term follow-up results in isolated proximal LAD disease. As fewer periprocedural events and more TVRs occur after DCA + stenting than after LIMA-LAD, they can be considered valuable alternatives to each other.

Comparison of late (four years) functional health status between percutaneous transluminal angioplasty intervention and off-pump left internal mammary artery bypass grafting for isolated high-grade narrowing of the proximal left anterior descending coronary artery

In a 4-year follow-up study, we compared functional health status (FHS) in patients randomized to surgery (n = 51) or angioplasty (n = 51) for an isolated narrowing of the proximal left anterior descending coronary artery. FHS was assessed with the Short Form-36 and the Minnesota Living with Heart Failure questionnaires. Although the occurrence of angina (p = 0.036) and major adverse cardiac and cerebrovascular events (p = 0.02) was significantly higher 4 years after angioplasty, FHS did not differ between treatments and was comparable to a healthy reference population.

Intimal Hyperplasia and Expression of Transforming Growth Factor-β1 in Saphenous Veins and Internal Mammary Arteries Before Coronary Artery Surgery

Background The development of fibromuscular intimal hyperplasia and subsequent graft failure remains an urgent problem in cardiac surgery. Transforming growth factor-β1 (TGF-β1) is involved in the pathogenesis of arteriosclerosis through induction of extracellular matrix proteins. We tested the hypothesis that intimal hyperplasia is already present in human saphenous veins and left internal mammary arteries before coronary artery bypass surgery and is associated with an increased expression of TGF-β1. Methods Forty-six segments of saphenous veins and 27 of left internal mammary arteries were collected from 50 patients undergoing coronary artery bypass surgery. Morphometric analysis was performed by microscopic computer analysis. Immunohistochemistry was performed with antibodies directed against TGF-β1, its latent binding protein (LTBP-1) and its type 2 receptor (RII). Results The incidence of intimal hyperplasia was significantly higher in saphenous veins (67.4%) than in mammary arteries (29.6%; p < 0.05). Saphenous veins and mammary arteries with intimal hyperplasia expressed more TGF-β1 (endothelial and intimal layers) and LTBP-1 (intimal and medial layers) when compared with corresponding vessels without hyperplasia (both groups p < 0.05). Endothelial and intimal RII expression was significantly higher in saphenous veins with intimal hyperplasia as compared with saphenous veins without hyperplasia ( p < 0.05). Transforming growth factor-β1 staining in the intima correlated with the presence of an intimal hyperplasia in saphenous veins (ρ = 0.317) and mammary arteries (ρ = 0.428). Conclusions Local TGF-β1 expression is associated with the presence of intimal hyperplasia in the examined vessels. Preexisting intimal hyperplasia is more prevalent and serious in saphenous veins than in left internal mammary arteries, giving further explanation to the superior long-term results of left internal mammary grafts.

Postoperative Changes in Duplex Ultrasound Velocity Characteristics in the Nonmobilized Right Internal Mammary Artery in Patients with Left Internal Mammary Artery Bypass Grafting

The internal mammary artery (IMA) is the conduit of choice in coronary revascularization because of its long-term patency. We analyzed the effect of left internal mammary artery (LIMA) harvesting on sternal perfusion. Diameters and velocity parameters of the nonmobilized right internal mammary artery (RIMA) were noninvasively analyzed with duplex ultrasound in 41 patients with LIMA myocardial revascularization pre- (2.6 +/- 5 days) and postoperatively (4.9 +/- 3.9 months). Data of 41 patients were analyzed; 38 patients underwent all examinations with adequate supraclavicular signals. The proximal RIMA diameter and all velocity parameters increased significantly at follow-up (3.1 +/- 0.6 vs. 3.2 +/- 0.5 mm, p = 0.03; diastolic peak velocity [DPV] 15 +/- 7 vs. 27 +/- 9 cm/sec, p < 0.0001; systolic peak velocity [SPV] 90 +/- 24 vs. 105 +/- 29 cm/sec, p < 0.02). This was more pronounced for the diastolic parameters and for all parameters in the proximal part of the RIMA than in the distal part (DPV 11.9 +/- 10.1 vs. 9.5 +/- 10.2 cm/sec, p = NS; SPV 14.9 +/- 33.9 vs. 7.4 +/- 26.0 cm/sec, p = NS). With longer time intervals of follow-up the increase in all diastolic velocity parameters became less pronounced. As demonstrated in the RIMA velocity parameters, patients with skeletonized LIMA grafts (n = 4) had significantly more flow, suggesting hyperemic flow, than patients with pedicled LIMA grafts (n = 34). Only in diastolic velocity integral (DVI) and systolic/diastolic velocity ratio (SDVRA) were there significant differences between diabetics (n = 9) and nondiabetics (n = 29) and only in DVI between female, (n = 8) and male (n = 30) patients. This study indicates that duplex ultrasound is a useful tool for noninvasive RIMA follow-up in LIMA myocardial revascularization.

Coronary steal from a left internal mammary artery coronary bypass graft by a left upper extremity arteriovenous hemodialysis fistula

In patients with end-stage renal disease undergoing hemodialysis, the upper extremity arteriovenous (AV) fistula is the dialysis access recommended by the DOQI guidelines for patients with appropriate vasculature. Upper extremity AV fistulae have long periods of usefulness, high flow rates, and low associated complication rates. Placement of AV access may result in increased cardiac output and increased cardiac oxygen demand in these patients. In general, cardiovascular complications from AV access have been limited. We report a novel cardiovascular complication of AV access in an end-stage renal disease patient with a coronary artery bypass graft employing the left internal mammary artery who experienced angina while undergoing hemodialysis. The angina was mediated at least in part by cardiac catheterization laboratory-documented steal of blood flow from the internal mammary artery graft. This phenomenon suggests the need to consider the impact of upper extremity access placement on blood flow to the left internal mammary artery in patients who previously have undergone placement of a coronary artery bypass graft. © 2002 by the National Kidney Foundation, Inc.

A simple technique for aortic valve replacement in patients with a patent left internal mammary artery bypass graft

Aortic valve replacement in patients with a patent left internal mammary artery graft is often a challenge because of the difficulties with dissection of the left internal mammary artery and optimum myocardial protection. We describe a simple technique of aortic valve replacement with a beating heart and continuous coronary perfusion for this difficult group of patients.