Left main stenosis

A significant left main stenosis (LMS), defined as a lesion with >50% stenosis, is present in 4% to 6% of all patients undergoing coronary angiography and in 30% of CABG patients. Given its proximal location... 

Chieffo A, Morici N, Maisano F, et al. Percutaneous treatment with drug-eluting stent implantation versus bypass surgery for unprotected left main stenosis a single-center experience. Circulation 2006 113 2542-7. 

Sclarovsky S, Nikus KC, Birnbaum Y. Manifestation of left main coronary artery stenosis is diffuse ST depression in inferior and precordial leads on ECG. J Am Coll Cardiol 2002 40 575. 

The indications for PTCA have been provided by the ACC/AHA and now span single- or multivessel disease as weU as asymp-tomatic and symptomatic patients (see Table 15-7). PTCA generally is not useful if only a small area of viable myocardium is at risk, when ischemia cannot be demonstrated, with borderline (<50%) stenosis or with lesions that are difficult to dilate, or in patients who are at high risk for morbidity or mortality or both (e.g., left main or equivalent disease or three-vessel disease). PTCA alone or in conjunction or sequentially with thrombolysis for acute Ml is discussed in Chap. 16. Stent placement accompanies balloon angioplasty in about 80% of cases in the United States. The current recommendations for PCI are provided in Table 15-7 based on class of angina. 

Taggart S, Kaul W, Boden WE, et al. Revascularization for unprotected left main stem coronary artery stenosis stenting or surgery. J Am Coll Cardiol 2008 51(9) 885-92. 

Palmerini T, Marzocchi A, Marrozzini C, et al. Comparison between coronary angioplasty and coronary bypass surgery for the treatment of unprotected left main coronary artery stenosis (the Bologna registry). Am J Cardiol 2006 98 54-9. 

Another major anatomical predictor of outcome in patients with CAD is the extent of atheromatous disease in the coronary artery tree. In the simplest categorization, patients can be separated into those with one-, two-, and three-vessel coronary disease based on the number of major epicardial vessels with significant coronary artery plaque. In the CASS Registry of medically-treated patients where the definition of clinically significant obstruction was a >70% reduction in the internal diameter of the vessel, the 12-year survival of patients with one-, two-, and three-vessel disease was 74%, 59%, and 40%, respectively (3). Stenosis of the left main artery >50% was also useful in predicting patient survival 12-year survival was 60% versus 49% for patients with two-vessel disease without and with left main disease respectively, and 41% and 35% for patients with three-vessel disease. As noted in the previous section, ejection fraction also strongly stratified survival in all three groups. 

Vigneswaran WT, Sapsford RN, Stanbridge RD. Disease of the left main coronary artery early surgical results and their association with carotid artery stenosis. Br Heart J 1993 Oct 70(4) 342-5. 

Rare complications as have been reported in literature are aortic and bronchial necrosis [58], bronchial stenosis [59], unilateral diaphragmatic paralysis [60], pulmonary infarction (especially in patients who have suffered pulmonary artery embolism), left main bronchial-esophageal fistula [61], and non-target embolization (colon, coronary and cerebral circulation) [62]. Especially the newer spherical embolic materials (tris-acryl gelatin) can traverse from the bronchial into the pulmonary circulation, and then through unoccluded pulmonary arteriovenous malformations into the systemic circulation [41]. 

Girard P, Baldeyrou P, Lemoine G, Grunewald D (1990) Left main-stem bronchial stenosis complicating bronchial artery embolization. Chest 97 1246-1248... 

Fig 9 5 Coronary sinus venography showing stenosis at the middle part of the main vessel (left anterior oblique in precluding left ventricular (LV) lead advancement. Angioplasty balloon inflation (b). Over-the-wire implantation of the LV lead in a lateral branch of the coronary sinus (c)... 

Fig.7.14a,b. Biloma in a 37-year-old woman with chronic stenosis of the main hepatic artery, fever, a Sonographic axial image on the left hepatic lobe shows two anechoic round lesions communicating with the dilated biliary tree, b Axial contrast-enhanced CT image shows two hypodense well-defined round lesions, communicating with the biliary tree... 

The most common airway problems are anastomotic dehiscence and bronchial stenosis due to strictures. The reason is mostly a lack of perfusion of the bronchial tree, as the donor airways depend on a retrograde pulmonary-to-bronchial arterial circulation until revascularization of the bronchus wall occurs. Ischaemia is greater on the right main bronchus than on the left, therefore anastomotic healing is better on the left and early stenotic problems or dehiscence occur on the right anastomosis more frequently than on the left side. In the early years of transplantation the en bloc technique was mainly performed with a high incidence of tracheal dehiscence, which prompted the development of bilateral lung transplantation. 

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