Iatrogenic left main coronary artery stenosis

Iatrogenic left main coronary artery stenosis is a potentially life-threatening complication of cardiac valve replacement surgery due to injury by perfusion cannulas. This requires prompt clinical recognition and diagnosis by repeat coronary angiography, and treatment by early coronary artery bypass grafting. We present 3 patients who had normal coronary arteries prior to valve replacement surgery, and who developed severe left main coronary artery stenosis after surgery. Accelerating angina and refractory ventricular arrhythmia were presenting clinical manifestations. Coronary artery bypass grafting was successfully performed in all 3 patients.     

Off-pump coronary revascularization for left main coronary artery stenosis

Experience of on- and off-pump coronary artery bypass in 379 patients with significant left main coronary artery stenosis was retrospectively reviewed. Beating-heart operations were performed on 219 patients between January 2001 and October 2007. Their results were compared with 160 who underwent revascularization under cardiopulmonary bypass during the same period. All patients had multivessel grafting via a median sternotomy. Both groups were comparable demographically. Off-pump patients received significantly fewer grafts per patient (3.21 +/- 0.86 vs 3.74 +/- 0.82). The use of moderate or high doses of inotropics (> 5 microg kg(-1) min(-1)) was more frequent in the on-pump group (44% vs 26%). Postoperative blood transfusion requirement was lower in off-pump patients, and fewer of them experienced worsening of preexisting renal insufficiency. There were 2 operative deaths in the on-pump group and 1 in the off-pump group. The off-pump procedure is safe and effective in patients with left main coronary artery disease.     

Radiation-induced stenosis of the left main coronary artery

Isolated left main coronary artery stenosis induced by mediastinal radiation is a well-documented but rare entity. Its clinical manifestations can be latent for many years, but its ominous sequela cannot be ignored. We report here such a patient presenting 16 yr postmediastinal radiation, the longest documented latency to date.     

Radiation-induced stenosis of the left main coronary artery

A case of isolated left main coronary artery stenosis ten years following irradiation of the mediastinum for Hodgkin's disease is presented. Aortic biopsies were consistent with changes suggestive of radiation arteritis.     

Stenting of unprotected left main coronary artery stenosis

Unprotected left main stenosis greater than 50% has traditionally been managed with coronary artery bypass surgery. There is now emerging evidence to support a percutaneous strategy adopting drug-eluting stents, especially in patients at high risk for surgery. This paper will review recent outcomes of both bare-metal and drug-eluting stent use for unprotected left main stenosis and summarise results of an Australian registry. Results of studies comparing the percutaneous approach to surgery will also be reviewed together with ESC and AHA/ACC current guidelines. Although percutaneous intervention of unprotected left main has been shown to be a safe and feasible procedure, unanswered questions remain. Large multi-centre randomised trials underway comparing percutaneous to surgical intervention will help clarify these ongoing issues.     

Patch angioplasty in isolated left main coronary artery stenosis

A 50 year old male with isolated left main coronary artery disease was surgically treated with saphenous vein patch angioplasty. Surgery results are reviewed by coronariography 2 months later and we comment its use as alternative technique in selected cases.     

Progression of left main coronary artery stenosis following left anterior descending coronary artery angioplasty

Although recent clinical experience indicates a high success rate, percutaneous transluminal coronary angioplasty (PTCA) is still associated with serious complications which usually occur during or shortly after the procedure and are principally related to the lesion or segment of vessel being dilated. We report 2 cases of subacute progression within months of left main stenosis following successful, uncomplicated left anterior descending (LAD) coronary PTCA. Identification of left main trunk involvement may mandate earlier follow-up or intervention.     

Pericatheterization risk factors in left main coronary artery stenosis

Patients with left main (LM) coronary artery disease (CAD) have an unexplained high incidence of complications during diagnostic cardiac catheterization. This study identifies pericatheterization risk factors for major complications in patients with LM CAD (stenosis at least 50%). Complications were defined as ventricular fibrillation not related temporally to coronary injection, persistent angina, acute myocardial infarction, profound hypotension and death during or within 24 hours of catheterization. One hundred seven consecutive cases of LM CAD (11 with complications and 96 without) were reviewed with respect to variables potentially related to complications. Patients who had angina in the 24 hours before catheterization were at increased risk. Four of 13 patients with angina (31%) and 7 of 94 (7%) without angina had complications (p less than 0.05). Distance from the catheter tip to the lesion also was related to complications (9 of 38 [24%] with tip 6.0 mm or less from lesion and 2 of 65 [3%] with tip more than 6.0 mm from lesion, p less than 0.05). No relaxation was found between complications and New York Heart Association functional class, technique (femoral vs brachial), performance of ventriculography, number of coronary injections, amount of contrast injected, severity of LM stenosis, number of major arteries with 75% or more diameter stenosis, mean arterial pressure, left ventricular end-diastolic pressure and left ventricular ejection fraction.     

Percutaneous coronary intervention for unprotected left main coronary artery stenosis

Hemodynamically significant left main coronary artery stenosis (LMCA) is found in around 4% of diagnostic coronary angiograms and is known as unprotected LMCA stenosis if the left coronary artery and left circumflex artery has no previous patent grafts. Previous randomized studies have demonstrated a significant reduction in mortality when revascularization by coronary artery bypass graft (CABG) surgery was undertaken compared with medical treatment. Therefore, current practice guidelines do not recommend percutaneous coronary intervention (PCI) for such a lesion because of the proven benefit of surgery and high rates of restenosis with the use of bare metal stents. However, with the advent of drug-eluting stents (DES), the long term outcomes of PCI with DES to treat unprotected LMCA stenoses have been acceptable. Therefore, apart from the current guidelines, PCI for treatment of unprotected LMCA stenosis is often undertaken in individuals who are at a very high risk of CABG or refuse to undergo a sternotomy. Future randomized studies comparing CABG vs PCI using DES for treatment of unprotected LMCA stenosis would be a great advance in clinical knowledge for the adoption of appropriate treatment.     

Clinical experience with left main coronary artery stenosis.

We report the clinical features and the results of investigation and surgery in 20 patients with significant left main coronary artery stenosis. All had moderate to severe angina; 8 had pain at rest. Three had dyspnoea as a major symptom. The electrocardiogram was abnormal in 17, with evidence of previous myocardial infarction in 10. Of the 11 patients exercised, 8 developed chest pain. Nine patients had a normal left ventriculogram. At coronary angiography all patients had major disease elsewhere in addition to the left main coronary artery stenosis. There were no deaths or major complications associated with this investigation. One patient was unsuitable for surgery because of diffuse left ventricular hypokinesia, one had a fatal myocardial infarction while awaiting operation, and there was one preoperative death. Sixteen of the 17 surgical survivors are free from angina. There has been a significant improvement in the maximum exercise capacity in the 10 patients who had pre- and postoperative exercise tests.     

孤立性左冠状动脉主干狭窄的诊治分析

目的分析孤立性左冠状动脉主干(左主干)狭窄的临床特点、造影所见和治疗方法.方法根据冠状动脉造影病变特点将129例左主干狭窄患者分为两组:孤立性左主干狭窄组7例;左主干合并一支或以上主要冠状动脉支狭窄组122例,对比分析两组间临床特点、造影所见和治疗方法.结果孤立性左冠状动脉主干狭窄的检出率为0.16%.6例表现为不稳定型心绞痛,1例为急性前壁心肌梗死.左主干狭窄部位:开口部4例,中部2例,叉口部1例.4例行外科手术,3例行冠状动脉支架术.与复合病变组相比较,孤立性左主干狭窄组女性的比例较高(57.1%vs20.5%,P<0.05),平均年龄较小[(52.3±5.1)岁vs(64.2±7.8)岁,P<0.001];开口部狭窄多见(57.1%vs17.2%,P<0.05).结论孤立性左冠状动脉主干狭窄以女性多见,以开口部狭窄多见,可选择外科和介入治疗.     

Clinical experience with left main coronary artery stenosis.

We report the clinical features and the results of investigation and surgery in 20 patients with significant left main coronary artery stenosis. All had moderate to severe angina; 8 had pain at rest. Three had dyspnoea as a major symptom. The electrocardiogram was abnormal in 17, with evidence of previous myocardial infarction in 10. Of the 11 patients exercised, 8 developed chest pain. Nine patients had a normal left ventriculogram. At coronary angiography all patients had major disease elsewhere in addition to the left main coronary artery stenosis. There were no deaths or major complications associated with this investigation. One patient was unsuitable for surgery because of diffuse left ventricular hypokinesia, one had a fatal myocardial infarction while awaiting operation, and there was one preoperative death. Sixteen of the 17 surgical survivors are free from angina. There has been a significant improvement in the maximum exercise capacity in the 10 patients who had pre- and postoperative exercise tests.     

非体外循环冠状动脉旁路移植术在左主干重度狭窄患者中的应用

目的总结左主干重度狭窄冠心病患者行非体外循环下冠状动脉旁路移植术（OPCAB）的治疗效果和临床经验。方法回顾分析2005年1月至2012年6月,83例左主干狭窄〉70％的患者接受了非体外循环下冠状动脉旁路移植术,其中27例急诊手术,三支病变62例,两支病变21例,术中改为体外循环5例;使用主动脉内球囊反搏7例。结果远端吻合口平均（3．34±0．83）个,死亡2例（2．4％）。随访2个月至2年,仅1例心绞痛复发,余者均未出现心绞痛症状。手术效果及手术并发症的发生与非左主干病变组差异无统计学意义（P〉0．05）。结论左主干重度狭窄行非体外循环下冠状动脉旁路移植术临床效果良好。     

Medical therapy in patients with left main coronary artery stenosis]

To elucidate the long-term prognosis of medically-treated patients with left main coronary artery (LMCA) lesions, 119 consecutive patients with LMCA lesions undergoing coronary angiography were analyzed retrospectively. Among these, 3 patients died soon after angiography and were excluded from this study. Among the remaining 116 patients, 22 were treated medically (Group M) for the following reasons: profound left ventricular (LV) dysfunction (3 patients), effective pharmacological treatment (10), and patients' refusal of surgical therapy (9). Among 94 patients who underwent coronary artery bypass graft (CABG), 83 patients survived (Group S). During the follow-up period, cardiac events occurred in 5 patients in Group M; cardiac deaths in 3, non-fatal myocardial infarction (MI) in one and late application of CABG in one. Two-year cardiac event-free rate after diagnosis was 77%, which remained unchanged thereafter. The cumulative survival rate was 83%. The incidence of cardiac events in Group M was higher than that in Group S (p < 0.01). However, cardiac event rates were similar between these 2 groups for patients with good collateral circulations to the left coronary arteries, no preceding MI and LV end-diastolic pressure less than 15 mmHg. We concluded that the Japanese patients with severe LMCA lesions who respond favorably to pharmacological intervention have unexpectedly good prognoses, however, obstructed collateral circulation to the left coronary system, the presence of preceding MI and high LV end-diastolic pressure were all high-risk factors for medically-treated patients.     

In-stent restenosis in idiopathic isolated ostial left main coronary artery stenosis

We describe the case of a 51-year-old female with previously undiagnosed congenitally corrected transposition of the great arteries (ccTGA) who was admitted to the hospital due to the exacerbated symptoms of heart failure for planned coronary angiography. Patient cardiac functional status appeared to have gradually regressed to New York Heart Association class III at the time of the admission. The chart reviews were performed. Coronary angiography did not reveal the occlusion of the coronary artery. Radiography, echocardiography, and multislice computed tomography confirmed newly diagnosed ccTGA.     

Takayasu's arteritis with ostial and left main coronary artery stenosis

Takayasu's arteritis with coronary artery involvement is rare, and there is little published information on the subject. Coronary angiographic and histopathologic studies have revealed coronary artery lesions in 9% to 11% of cases. Coronary artery involvement consists mostly of stenosis or occlusion of the coronary ostia. We report the case of a 19-year-old woman who presented with crescendo angina. Upon investigation, we found that our patient had ostial and left main coronary arterial stenosis with left-dominant circulation; therefore, we decided that an arterial Y graft, performed on a beating heart, would provide better perfusion to the compromised myocardium than would a single graft to the left anterior descending artery. In addition, use of the Y graft obviated the need to perform a proximal anastomosis on an inflamed, edematous ascending aorta, and it conferred long-term graft patency of the internal mammary arteries. Timely coronary artery bypass grafting relieved our patient's angina, and in early follow-up she has shown good effort tolerance.     

左冠状动脉主干狭窄195例临床分析

目的　探讨左冠状动脉主干 (左主干 )狭窄的临床特点、诊断及治疗方法。方法　按冠状动脉造影 (CAG)结果将冠状动脉管径狭窄程度分为轻、中、重及完全闭塞 4组 ,并按其他冠状动脉受累情况分为孤立左主干组 9例 (4 6 2 % )、左主干 +1支组 15例 (7 6 9% )、左主干 +2支组 5 3例(2 7 18% )、左主干 +3支组 118例 (6 0 5 1% )。结果　经CAG确诊的 2 892例冠心病患者中左主干狭窄 195例 (6 74 % ) ,检出率低。临床主要表现为不稳定心绞痛 16 4例 (84 1% ) ,心肌梗死 (MI) 12 5例(6 4 1% )。冠状动脉旁路移植术 (CABG) 5 7例 ,术后 4 7例 (84 2 % )患者心绞痛消失。 5例行无保护性左主干病变直接支架术 ,术后无心绞痛再发。结论　左主干狭窄临床症状严重。CAG是确诊的唯一手段。CABG为最佳治疗方法。无保护性左主干病变直接支架术可用于有适应症患者。     

Iatrogenic left main coronary artery stenosis following aortic valve replacement

A case of severe iatrogenic fibrous left main coronary arterystenosis following aortic valve replacement (Hall-Kaster prosthesis)is documented clinically, angiographically and histologically.Reported histological data of this rare complication of valvereplacement are reviewed. The onset of ischaemic symptoms inthe first six months after valve replacement is highly suggestiveof iatrogenic coronary artery stenosis, and urgent coronaryangiography is recommended.     

Composite Y-graft for syphilitic ostial stenosis in left main coronary artery

Coronary ostial stenosis is one of the cardiac manifestations of tertiary syphilis and should be perceived as a disorder of the aorta. A 45-year-old man with no coronary risk factors except smoking developed severe isolated ostial stenosis in the left main coronary artery. He underwent emergency bypass surgery using the bilateral internal thoracic arteries as a composite Y-graft, and recovered uneventfully.