Project description:BackgroundInternal thoracic artery (ITA) grafts are commonly used for coronary artery bypass grafting, with dissection to the graft being a rare occurrence. Herein, we describe a case of spontaneous ITA graft dissection occurring 11 years after grafting, with no clear precipitating incidence.Case summaryThe patient was a 61-year-old man who presented with a 3-month history of chest pain and dyspnoea. Dissection of the left internal thoracic artery (LITA) graft was observed on angiography, with a thrombolysis in the myocardial infarction (TIMI) grade 2 blood flow. Intravascular ultrasound confirmed an intimal tear in the proximal graft, with an intramural haematoma. In the absence of atherosclerotic changes, the dissection was treated directly using multiple drug-eluting stents to prevent further extension of the intramural haematoma proximally into the subclavian artery and distally to the anastomosis site. Post-procedural angiography revealed an enlarged true lumen of the LITA, shrinking of the intramural haematoma, and improvement in blood flow to a TIMI grade 3. Chest symptoms resolved immediately after the procedure, with the patient remaining asymptomatic over the 6-month period following the procedure.DiscussionDissection of the ITA graft can occur spontaneously long after the initial grafting. Intravascular ultrasound is useful for diagnosis. Ensuring adequate coverage of the edges of the dissection with stenting could prevent further extension of the intramural haematoma.
Project description:BackgroundThe inter-arterial anomalous course of the left main coronary artery (LMCA) originating from the right coronary sinus of Valsalva is a rare, though potentially lethal pathology. Coronary artery bypass grafting is a potential surgical therapy with previously reported success, however, there is concern for the possibility of graft occlusion in the setting of competitive native vessel flow.Case summaryA 48-year-old gentleman presented to our facility with a non-ST elevation acute coronary syndrome. A malignant anomalous course of the LMCA was confirmed using invasive coronary angiography and computed tomography (CT). The patient underwent surgical revascularization of the left anterior descending artery with a left internal mammary artery (LIMA) graft, which was found to be atretic on follow-up CT. Seven years later the patient underwent repeat CT imaging, which confirmed recanalization of the previously atretic LIMA.DiscussionWe present the first documented case of a patient with spontaneous recanalization of an occluded LIMA following bypass surgery for an inter-arterial anomalous course of the LMCA. We postulate that the dynamic obstruction of the anomalous LMCA led to variable flow dependence on the bypass graft and subsequent atresia of the LIMA, due to the favourable native flow conditions in the absence of significant obstructive coronary disease. The exact mechanism of LIMA recanalization remains unclear, but in our case may have been partly mediated by a small increase in left main plaque.
Project description:Guide-catheter-induced ostial coronary artery dissection is a feared complication of percutaneous coronary intervention, but thankfully the incidence is low. We describe a case of catheter-induced ostial dissection of the left internal mammary artery (LIMA) with multiple radial jump grafts during percutaneous coronary intervention of radial graft bifurcation disease via the LIMA. The dissection led to loss of flow and profound haemodynamic compromise and cardiac arrest as the LIMA supplied the majority of the myocardium in this patient. Intravascular ultrasound was not immediately available, so an Export AP thrombus aspiration catheter (Medtronic) was used over the coronary wire in place to allow the injection of contrast while simultaneously pulling back on the catheter to delineate the extent of the dissection and guide accurate drug-eluting stent placement. The report is a cautionary tale to the reader to treat the LIMA with respect and think long and hard before considering any interventional procedure that uses the LIMA as a conduit.
Project description:ObjectivesTo assess whether instantaneous wave - free ratio (iFR) value is associated with left internal mammary artery (LIMA) graft failure at 12 months follow-up post coronary artery bypass graft (CABG).BackgroundData suggests bypass to a non-significant left anterior descending artery (LAD) lesion due to visual over-estimation may lead to LIMA graft failure. Implementing iFR may result in better arterial graft patency.MethodsIn iCABG (iFR guided CABG) study patients planned to undergo an isolated CABG procedure was prospectively enrolled and iFR was performed for LAD. Coronary computed tomography angiography was performed at 2 and 12 months follow-up. The primary endpoint of this study was to determine the rate of LIMA graft occlusion or hypoperfusion at 2 and 12-months follow-up. We considered a composite secondary endpoint of Major adverse cardiovascular and cerebrovascular event (MACCE) as a secondary outcome.ResultsIn total 69 patients were included with no differences regarding age, sex and risk factors. At 2 months, 50 of LIMAs with pre-CABG iFR median 0.855 (0.785 - 0.892) were patent. Hypoperfusion was found in 8 LIMAs (median iFR 0.88 (0.842 - 0.90)). While, 7 LIMAs (median iFR 0.91 (0.88 - 0.96)) were occluded (p = 0.04). At 12 months, when iFR of LAD was >0.85: just 12 (31.6% out of all patent LIMAS) grafts were patent and 24 (100.0% out of all hypoperfused/occluded) grafts were hypoperfused or occluded (p < 0.001). In terms of MACCE, no difference (p = 1.0) was found between all 3 groups divided according to iFR value.ConclusionsInstantaneous wave - free ratio value above 0.85 in LAD is a powerful tool predicting LIMA graft failure at 1-year follow up period.
Project description:BackgroundAvulsion of the left internal mammary artery (LIMA) graft near the anastomosis to the left anterior descending artery (LAD) artery post-coronary artery bypass grafting (CABG) is a rare but potentially catastrophic complication which can result in sudden ischaemia, haemodynamic compromise and life-threatening bleeding into the pericardium.Case summaryWe report a case of a spontaneous LIMA graft avulsion at the site of the anastomosis to the LAD artery, which occurred 4 weeks post-conventional CABG surgery and resulted in anterior myocardial infarction (MI), cardiac tamponade and cardiogenic shock. This life-threatening event was treated by deploying a covered stent in the LAD artery and by coiling the dehisced LIMA graft.DiscussionTo our knowledge, this is the first report of late LIMA graft avulsion that has been uniquely and successfully treated by percutaneous coronary intervention.
Project description:It is sometimes difficult to identify the culprit lesion and treatment strategy in patients with acute coronary syndrome who have complex coronary lesions and jeopardized left internal mammary artery graft. This report describes a heart team approach for a non-ST-segment elevation myocardial infarction case with complex coronary vasculature. A 73-year-old man presented to the emergency department with crescendo angina. He had a history of total aortic arch replacement with concomitant coronary artery bypass graft using left internal mammary artery. Emergent coronary angiography demonstrated severe stenosis at left main trunk bifurcation caused by calcified nodule. While the bypass graft to left anterior descending coronary artery was patent, the proximal segment of left subclavian artery was occluded. Following the prompt discussion with our heart team, we performed percutaneous coronary intervention in the first step for treating the left main stenosis using rotational atherectomy into the unprotected left circumflex artery. After clinical recovery, stress myocardial scintigraphy identified the presence of anteroseptal ischemia, which indicated coronary subclavian steal syndrome due to left subclavian artery occlusion. Contrast-enhanced CT visualized that the occlusion originated from the anastomosis, suggesting the potential procedural risk of endovascular treatment by dilatation. Our heart team discussed again and decided to undergo axillo-axillary artery bypass surgery. He was discharged 8 days after the surgery without any sequelae. This is the rare case report of non-ST-segment elevation myocardial infarction who had similar condition to coronary subclavian steal syndrome after total aortic arch replacement. This case highlights the importance of a collaborative approach of the heart team to identify the best therapeutic strategy in a patient with complex coronary vasculature.
Project description:BackgroundWhile internal mammary artery (IMA) has become a major conduit of coronary artery bypass graft (CABG) surgery, subclavian artery stenosis (SAS) could cause subsequent coronary events due to ischemia of myocardial territory supplied by IMA. Clinical characteristics and cardiovascular outcomes of SAS-related IMA failure (SAS-IMAF) remain to be fully determined yet. Therefore, the current study was designed to characterize SAS-IMAF in patients receiving CABG with IMA.MethodsThis is a retrospective observational study which analyzed 380 patients who presented acute coronary syndrome/stable ischemic heart disease (ACS/SIHD) after CABG using IMA (2005.01.01-2020.10.31). SAS-IMAF was defined as the presence of myocardial ischemia/necrosis caused by SAS. Clinical characteristics and cardiovascular outcomes [major adverse cardiovascular events (MACE) = cardiac death + non-fatal myocardial infarction + non-fatal ischemic stroke], were compared in subjects with and without SAS-IMAF. Multivariate Cox proportional hazards model and propensity score-matched analyses were used to compare cardiovascular outcomes between those with and without SAS-IMAF.ResultsSAS-IMAF was identified in 5.5% (21/380) of study subjects. Patients with SAS-IMAF are more likely had a history of hemodialysis (P<0.001), stroke (P<0.001) and lower extremity artery disease (P<0.001). Furthermore, SAS-IMAF patients more frequently presented ACS (P=0.002) and required mechanical support (P=0.02). Despite SAS as a culprit lesion causing ACS/SIHD, percutaneous coronary intervention was firstly selected in 47.6% (10/21) of them. Consequently, 33.3% (7/21) of SAS-IMAF patients required additional revascularization procedure (vs. 0.3%, P<0.001). During 4.9-year observational period, SAS-IMAF exhibited a 5.82-fold [95% confidence interval (CI): 2.31-14.65, P<0.001] increased risk of MACE. Multivariate Cox proportional hazards model [hazard ratio (HR) 4.04, 95% CI: 1.44-11.38, P=0.008] and propensity score-matched analyses (HR 2.67, 95% CI: 1.06-6.73, P=0.038) consistently demonstrated the association of SAS-IMAF with MACE.ConclusionsSAS-IMAF reflects a high-risk phenotype of polyvascular disease, underscoring meticulous evaluation of subclavian artery after CABG using IMA.
Project description:ImportanceThe relative safety and patency of skeletonized vs pedicled internal mammary artery grafts in patients undergoing coronary artery bypass graft (CABG) surgery are unknown.ObjectiveTo investigate the association of skeletonized vs pedicled harvesting with internal mammary artery graft patency and clinical outcomes 1 year after CABG surgery.Design, setting, and participantsThis study was a post hoc analysis of the multicenter, randomized, double-blind, placebo-controlled Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) clinical trial, which enrolled 27 395 patients from 602 centers in 33 countries from March 2013 through May 2016. Eligibility criteria for the trial included CABG surgery for coronary artery disease with at least 2 grafts implanted and an estimated glomerular filtration rate of at least 30 mL/min. A total of 1002 of 1448 patients were randomized to the CABG arm of the COMPASS trial and underwent skeletonized (282 [28.1%]) or pedicled (720 [71.9%]) internal mammary artery harvesting. The patients had evaluable angiography results 1 year after surgery. Data were analyzed from October 11, 2019, to May 14, 2020.InterventionsPatients underwent graft harvesting with either the pedicled technique or skeletonized technique.Main outcomes and measuresThe primary outcome was graft occlusion 1 year after CABG surgery, as assessed by computed tomography angiography.ResultsA total of 1002 patients underwent skeletonized (282 [28.1%]; mean [SD] age, 65.9 [8.1] years; 229 men [81.2%]; 194 White patients [68.8%]) or pedicled (720 [71.9%]; mean [SD] age, 64.8 [7.6] years; 603 men [83.8%]; 455 White patients [63.2%]) internal mammary artery harvesting. Rates of internal mammary artery graft occlusion 1 year after CABG surgery were higher in the skeletonized group than in the pedicled group (33 of 344 [9.6%] vs 30 of 764 [3.9%]; graft-level adjusted odds ratio, 2.41; 95% CI, 1.39-4.20; P = .002), including the left internal mammary artery to left anterior descending artery (21 of 289 [7.3%] vs 25 of 725 [3.4%]; graft-level adjusted odds ratio, 2.10; 95% CI, 1.14-3.88, P = .02). After a mean follow-up of 23 months, skeletonized graft harvesting was also associated with a higher rate of major adverse cardiovascular events (20 [7.1%] vs 15 [2.1%]; adjusted hazard ratio, 3.19; 95% CI, 1.53-6.67; P = .002) and repeated revascularization (14 [5.0%] vs 10 [1.4%]; adjusted hazard ratio, 2.75; 95% CI, 1.10-6.88; P = .03).Conclusions and relevanceThis post hoc analysis of the COMPASS randomized clinical trial found that harvesting of the internal mammary artery during CABG surgery using a skeletonized technique was associated with a higher rate of graft occlusion and worse clinical outcomes than the traditional pedicled technique. Future randomized clinical trials are needed to establish the safety and patency of the skeletonized technique.Trial registrationClinicalTrials.gov Identifier: NCT01776424.
Project description:BackgroundAcute dissection of the left internal mammary artery (LIMA) graft in patients with previous cardiac bypass surgery is a rare but potentially life-threatening condition.Case summaryA 58-year-old man with history of coronary artery disease and bypass surgery 15?years ago presented with acute coronary syndrome (non-ST-elevation myocardial infarction, NSTEMI). Angiography showed severe three-vessel disease with occlusion of a saphenous vein graft (SVG) to the first diagonal branch but patents grafts to left artery descendent (LIMA) and SVG to the right coronary artery. No coronary intervention was performed and the patient was treated medically (aspirin and ticagrelor) and discharged home after 6?days. Three months later, the patient again was admitted to the hospital with acute coronary syndrome (NSTEMI) and developing cardiogenic shock. Angiography now showed an extensive flow limiting dissection of his LIMA graft with the dissection starting at the ostium of the LIMA. After implantation of an Impella 2.5, percutaneous coronary intervention (PCI) of the graft was performed under guidance by optical coherence tomography (OCT) leading to implantation of a drug-eluting stent into the ostium of the LIMA and repeated balloon dilatations of the medial and distal parts of the graft. Antegrade flow was established and the patient's condition improved so that the Impella was removed in the cath lab. After an uneventful course, the patient was discharged home after 6?days. Elective repeat angiography after 8?weeks showed an excellent functional result without persisting signs of LIMA dissection or stenosis.DiscussionAcute dissection of a LIMA graft is a rare event that may lead to a life-threatening condition. According to the literature, LIMA dissection happens during coronary interventions in approximately half of the cases but it also may evolve spontaneously. However, as seen from our case, there might be a substantial delay between LIMA angiography and the clinical onset of dissection. In the vast majority of cases, dissection of LIMA can be treated by PCI. The use of Impella as reported for the first time in this case may improve the safety of the procedure. In accordance to PCI of the native coronary arteries, it seems possible to leave non-flow limiting dissections in cases of extensive disease in order to avoid the late complications of complete stenting of the graft.