Kinking of internal mammary grafts: report of two cases and surgical correction

Nonatheromatous Coronary Kink Causing Angiographic Obstruction: A Rare Structural Anomaly

Ischemic symptoms may be explained by a multitude of coronary pathologies, including coronary artery tortuosity, atherosclerosis, fibromuscular dysplasia, vasculitis, coronary vasospasm, or microvascular disease. We present an unusual case of coronary kinking in a patient presenting with exertional jaw pain in the absence of atherosclerotic risk factors. Multimodality imaging, coronary imaging, and coronary physiology helped establish the diagnosis and guide management.

Near-fatal kinking of mammary graft due to emphysematous lung disease

Left internal mammary artery grafting is commonly used in elective coronary artery bypass graft surgery. We report a near-fatal case with graft kinking upon sternal closure due to distended, emphysematous lungs impinging on the mammary graft. After the sternum was closed, the patient suffered a severe hemodynamic deterioration. Surgical examination revealed kinking of his left internal mammary artery upon sternal closure due to distended, emphysematous lungs impinging on the mammary graft. Using an off-bypass technique, the kink in the mammary graft to the left anterior descending artery was removed by moving the origin of the left internal mammary artery to a hooded graft of a saphenous vein graft instead. In this position, the graft no longer was impinged upon by the distended emphysematous lungs. Subsequently, the patient’s sternum was closed without hemodynamic impingement. Although chronic obstructive pulmonary disease is well described to increase complications in coronary artery bypass graft surgery, it has not been previously associated with the kinking of a left internal mammary artery. This report highlights another contribution that chronic obstructive pulmonary disease can make to increased morbidity following coronary artery bypass graft surgery and alerts readers to watch for this complication in susceptible patients.

Transient right internal thoracic arterial graft kink related to respiratory movements: documentation of its existence, relevance and proposed management

In this case report, we provide the first detailed description of an intermittent mechanical kink of a right internal thoracic artery (ITA) graft to the left anterior descending coronary artery secondary to respiratory movements, and its assessment by pressure wire derived fractional flow reserve (FFR). The patient presented with recurrent unstable angina and documented anterior/anterolateral ischemia. Persistent symptoms were attributed to the ITA kink and stenting was planned on clinical grounds. However, the lesion proved not physiologically significant when FFR was assessed after intermittency related to respiratory movements was documented. Complex stenting was therefore avoided and medical therapy was prescribed for distal diagonal disease. We therefore propose that intermittency should be actively investigated when a kink is documented in a coronary bypass graft by conventional angiography (using dedicated angiographic evaluation in maximal inspiration and expiration). Furthermore, when this type of lesion is encountered, we suggest that it should be assessed physiologically using pressure wire derived FFR before potentially complex interventions are considered.

Rapid diagnostics and treatment of early complications after CABG surgery: a life saver

Early graft failure after CABG surgery may lead to severe adverse events and death. Because the cause of the graft failure can vary, rapid diagnostic management is mandatory in order to address these complications appropriately. In the present 2 cases, patients who underwent CABG procedures showed typical electrocardiograms and serology of a perioperative myocardial ischemia shortly after surgery. In the first case, a rapidly performed coronary angiogram revealed a torqued right CABG, which was detorqued and, in order to avoid further torsion, fixated to the pericardium in a redo procedure. In the second case, the patient underwent a revascularization by means of percutaneous coronary intervention with stent implantation for severe stenosis due to a localized dissection of the vein graft, diagnosed on coronary angiogram. The further postoperative course of both patients was smooth and both could be discharged on day 8 and 11 after initial surgery, respectively.

Fatal left cardiac failure caused by external compression of left internal mammary artery graft in an accident: a case report

We report for the first time a case of a 54 years old man with a fatal motorcycle accident due to an external bleeding compression of left internal mammary artery graft to the left anterior descending artery. The possibility of cardiac failure in trauma caused by external compression or traumatic injury of the graft should be considered in people who previously underwent coronary artery bypass graft surgery.

Kinking of internal thoracic artery graft without symptoms: should it be revised?

BACKGROUND

Surgery or intervention therapy has been performed to correct kinks of internal thoracic artery (ITA) grafts. The aim of this study was to evaluate the natural course of the ITA graft kink and to clarify whether surgery or intervention therapy should be performed in asymptomatic patients during the early postoperative period.

METHODS

We investigated the early and follow-up angiographic results of ITA graft kinks in 7 consecutive patients who did not undergo surgical or interventional correction. The graft diameter and percentage of diameter stenosis at the kink site were compared between the early postoperative angiography and the follow-up angiography.

RESULTS

Early postoperative angiography revealed that the diameter stenosis at the kink site was 60.1% +/- 6.9% (range, 51 to 69) and the diameter at the kink site was 0.92 +/- 0.20 mm (range, 0.63% to 1.25%). The ITA kinks disappeared in all the patients and the diameter of the ITA graft adjacent to the kink was not significantly changed on the follow-up angiography. No luminal irregularity or indentation was shown. All the patients had been free from cardiac events until the follow-up angiography.

CONCLUSION

Kinking of an ITA graft that's seen on the early postoperative angiography might improve without surgery or intervention. The natural course of ITA graft kinks should be considered when detecting these kinks on the early postoperative angiography when the patient is asymptomatic.

Pitfalls of Skeletonized Internal Thoracic Artery:

BACKGROUND AND AIM OF THE STUDY

Skeletonization of the internal thoracic artery (ITA) has several advantages: sequential bypass grafting can be easily performed, and a graft of increased length can make the distal coronary artery accessible. However, kinking of the grafts has been observed on postoperative angiograms in a few cases. We investigated whether there were significant differences in the frequency of graft kinking and stenosis degree at the kink site between pedicled and skeletonized grafts.

METHODS

Postoperative angiography was performed for all cases. In pedicled (n = 65) and skeletonized (n = 129) groups, the results of postoperative graft angiography were analyzed to investigate the presence of graft kinking and stenosis degree at the kink site.

RESULTS

Kinking was observed in 4 (5.9%) and 9 (3.9%) arteries in the pedicled and skeletonized groups, respectively (p = 0.341). The stenosis degree at the kink site (mean +/- SD) was significantly higher in the skeletonized group (47.2 +/- 16.8%) than in the pedicled group (23.5 +/- 13.7%), (p = 0.032). In four patients in whom early postoperative angiography showed a kink with more than 50% stenosis, late-term angiography was performed. All four cases showed regression of the stenosis degree at the kink site.

CONCLUSIONS

When the ITA had a kink, the stenosis degree at the kink site was significantly higher in the skeletonized group than in the pedicled group. Late angiography often reveals regression of stenosis at the kink site. Immediate intervention need not always be performed if the patient has no angina caused by a stenotic lesion at the kink site.

Use of stents to treat kinks causing obstruction in a left internal mammary artery graft

Left internal mammary arteries (LIMA) are used routinely as grafts to the left anterior descending coronary artery (LAD) in selected patients undergoing coronary artery bypass graft (CABG) surgery because of better long-term patency rates. Pathology other than fibrointimal hyperplasia, accelerated atherosclerosis, or thrombus can sometimes cause obstructive lesions in such grafts. This report illustrates a kink in a LIMA graft to the LAD causing an obstructive lesion shortly after surgery and describes the subsequent management of this lesion with intracoronary stents.

Functional assessment of internal mammary artery bypass grafts: case reports and review of the literature

The utility of intra-arterial Doppler flow in assessing internal mammary artery (IMA) bypass grafts has infrequently been reported. Two patients are described in which Doppler evaluation of the IMA graft provided valuable diagnostic information prior to intervention. Also provided is a review of the available literature concerning evaluation of pathology in IMA grafts.

Emergency left main stenting in the management of postcoronary bypass graft surgery (CABG) ischemia

Angioplasty has been used in the management of postcoronary bypass graft myocardial ischemia/infarction. A stent was successfully deployed in the left main artery in a patient with postcoronary bypass graft ischemia with hemodynamic instability. This case illustrates the potential use of emergency left main stenting in a selected patient with peri-operative ischemia, who was considered high risk for re-operation.

Balloon angioplasty of the internal mammary artery trunk for early postoperative ischemia: a case report

In this case report kinking of the internal mammary artery graft with possible superimposed spasm is described. Angiographic diagnosis was made 72 hrs following coronary artery bypass surgery and the lesion was successfully dilated with balloon angioplasty.

Torsion of an internal mammary graft during percutaneous transluminal angioplasty: a case report

A successful percutaneous transluminal angioplasty of the distal anastomosis of a tortuous left internal mammary artery graft to the left anterior descending coronary artery was complicated by the development of a focal lesion in the mid-graft region. Dilatation at the site failed to improve the angiographic appearance. Withdrawal of the guidewire resulted in immediate resolution of the apparent mid-graft lesion. The abnormality is felt to have been due to torsion of the graft upon itself, caused by guidewire and balloon catheter manipulation.