Total left main coronary artery occlusion. The acute, the chronic, and the iatrogenic

Isolated and Significant Left Main Coronary Artery Disease: Demographics, Hemodynamics and Angiographic Features

Left main coronary artery disease carries a poor prognosis. The etiology of isolated and significant left main coronary artery (ILMCA) disease is not well understood. Studies so far were limited by small numbers. The authors identified 46 patients with ILMCA disease from their database over 10 years (group I) and compared them with 83 consecutive patients undergoing catheterization (group II). They also compared patients with ostial vs distal ILMCA disease. Group I represented 0.1% of catheterization patients. The demographic profile and atherosclerotic risk factor profile of the 2 groups as well as ostial and distal ILMCA disease were compared. This is the largest study of ILMCA disease. Risk factors for atherosclerosis were commonly seen. Nonatherosclerotic causes of ILMCA disease were not seen. This study suggests coronary atherosclerosis as the predominant cause of ILMCA disease. ILMCA disease is more common in women. Diabetes is more commonly associated with distal ILMCA lesion. There is a trend suggesting that ostial ILMCA lesion is more common in smokers and women.

Chronic total occlusion of the left main coronary artery with normal left ventricular motion: the occluded site confirmed by three-dimensional computed tomography

Total occlusion of the left main trunk (LMT) frequently results in sudden cardiac death. As a result, it is rarely observed on coronary arteriogram. There are only a few reports on chronic total occlusion of the LMT. Most patients present with recent, severe angina, but it is not easy to distinguish chronic total occlusion of the LMT from other types of severe coronary heart diseases. Here, we report a very rare case of chronic total occlusion of the LMT. The patient is a 38-year-old female with a history of three normal deliveries. Chronic total occlusion of the LMT was suspected on coronary arteriogram 2 years previously in the other hospital; however, she continued working as a part-time employee at a supermarket. She was referred to our hospital because of slightly increased effort angina and shortness of breath. The final diagnosis and the site of occlusion were determined by three-dimensional computed tomography (3-D CT). The patient underwent coronary artery bypass graft (CABG) surgery, and ischemic symptoms completely disappeared.

Collateral circulation from the conus coronary artery to the anterior descending coronary artery: assessment using multislice coronary computed tomography

The prognosis of patients with coronary artery disease largely depends on the presence of a collateral circulation. The location and extent of the collateral circulation is highly variable and these parameters determine whether or not ischemic symptoms occur and whether left ventricular contractility is abnormal. The collateral circulation is generally established through small-caliber distal vessels, although many different forms have been described. We report on three patients with severe left coronary artery disease and collateral circulation through a large conus coronary artery that joined a proximal or medial segment of the left anterior descending coronary artery. In all three cases, left ventricular function was preserved.

Occlusion of the left main coronary artery and collateral circulation via the conus branch

We report the case of a 71-year-old-man, a smoker, admitted for unstable angina. Subsequent investigation revealed complete proximal occlusion of the left main coronary with an unusual collateral circulation. The left coronary artery was filled by a large conus branch originating from the right sinus of Valsalva. This case shows the importance of looking for atypical collateral circulation in patients with chronic occlusion of the left main coronary artery and normal left ventricular function.

Chronic total occlusion of the left main coronary artery

Total chronic occlusion of the left main coronary artery is a rare angiographic finding in a catheterization laboratory and its treatment rarely is reported. We describe a patient with angiographic findings of chronic total occlusion of the left main coronary artery with left coronary circulation collateralized from the right coronary artery.

Left main coronary artery stenosis: state-of-the-art

Patients with stenosis of the left main coronary artery present difficult challenges. The risks associated with this lesion have been known since the early days of angiography when patients were found to have increased mortality during follow-up. This information led to the general guidelines that surgical revascularization should be considered the treatment of choice in patients with significant left main coronary artery stenosis. Current advances in invasive cardiology have brought important information to the field. Intravascular ultrasound is now used routinely to evaluate angiographically indeterminate lesions with criteria now set forward as to what constitutes an indication for revascularization. Stents have even further dramatically changed the landscape. There are substantial issues, however, that need to addressed. These include the following: (1) the effect of specific lesion location on outcome - it is known that patients with distal bifurcation left main disease have worse outcome; (2) the potential for subacute thrombosis of the left main coronary artery; (3) the impact of left ventricular function and patient comorbidities irrespective of the degree and location of left main coronary artery stenosis; and (4) the risk-benefit ratio of stenting versus coronary artery bypass graft surgery. These issues are currently being addressed in two seminally important trials including the SYNTAX trial, which randomizes patients with left main and/or three-vessel disease to either coronary artery bypass graft surgery or a TAXUS drug-eluting stent. This trial is in the final stages of patient recruitment and will have important implications for the field. The other trial is the COMBAT trial, which is focused exclusively on left main coronary artery stenosis and randomizes patients with left main coronary artery disease either to a Sirolimus-eluting stent (Cypher, Johnson and Johnson Cordis, USA) or to coronary artery bypass graft surgery. The field of left main coronary artery disease continues to expand in terms of the evidence available for optimal patient evaluation and selection of treatment modalities.

Surgery for Chronic Total Occlusion of the Left Main Coronary Artery- Myocardial Preservation

We report seven patients with chronic total occlusion of the left main coronary artery that were operated in our institution and discuss the myocardial preservation options in these patients. In addition to total occlusion of the left main coronary artery, three patients also had severe lesions of right coronary artery. Prior myocardial infarction history and significantly depressed left ventricle functions were detected in all three patients with right coronary artery lesions. Five patients were operated on cardiopulmonary bypass while two patients were operated off pump. All patients received alternating antegrade/retrograde cardioplegia for myocardial preservation. In patients with simultaneous right coronary artery disease we first established the origin of the collaterals to the left coronary system. For patients with collaterals arising from the right coronary artery segment distal to the right coronary artery lesion, the antegrade component was administered through the saphenous vein graft bypassed to a distal part of right coronary artery segment. Thus we have achieved a more effective distribution of the antegrade cardioplegia. In off-pump-operated patients the left coronary system was revascularized before the right coronary system. Postoperative low cardiac output syndrome occurred in only one patient who was operated off pump. There was no operative and early mortality. Mean follow-up was 32 +/- 21.42 (range, 4 to 60) months. Alternating antegrade/retrograde cardioplegia was used with acceptable results in patients with total occlusion of the left main coronary artery. In patients with simultaneous RCA lesion we recommend regulation of the antegrade component based on the origin of collaterals that supplies the left coronary system. In off-pump-operated patients we suggest avoiding of clamping of right coronary artery at the beginning of the operation while it still supplies all the coronary circulation.

Stress thallium-201 myocardial scintigraphy in patients with complete occlusion of the left main coronary artery

Complete occlusion (CO) of the left main coronary artery (LMCA) is a rare but often fatal condition. The diagnosis is frequently missed because the signs and symptoms are often obscure and diverse. We describe three patients with CO-LMCA who showed unusual myocardial scintigraphic findings. The patients had extensive right-to-left collateral channels and decreased uptake and washout rates at the basal anterior and anterolateral portions of the heart wall during stress thallium-201 scintigraphy. The basal anterior to anterolateral portion of the heart wall is the most distant from the collateral artery and should be the most ischemic area shown during exercise, resulting in this scintigraphic pattern. This scintigraphic finding may be useful for the noninvasive diagnosis of CO-LMCA.

Left main coronary artery disease in adults younger than 50 years: a comparison with older patients

Left main coronary artery (LMCA) disease is a potentially lethal disease that can be effectively treated if it is recognized expeditiously. To determine whether clinical signs and symptoms vary with age, we examined data from 100 patients with angiographically significant LMCA disease (> or =50% stenosis). The majority of patients had myocardial infarction (32%) or Braunwald class I unstable angina (46%). There were no differences in initial symptoms, electrocardiographic findings (normal or only nonspecific changes in 52% of patients), or left ventricular function (normal or only mildly impaired in 76% of patients) between younger patients (< 50 yr; n = 29) and older patients (n = 71). Severe atherosclerosis was common in both groups. Risk factor profiles were different, however, in that diabetes mellitus (10% vs. 34%; P = 0.028) and hypertension (38% vs. 73%; P = 0.002) were less common and tobacco use was more common (79% vs. 39%; P <0.001) in younger patients. In summary, age influenced the risk factors associated with but not the clinical signs and symptoms of LMCAD.

Total occlusion of the left main and proximal right coronary artery: case report and review of the literature

Chronic total left main coronary artery occlusion at angiography is very rare, and there are only four cases reported with concomitant total right coronary artery occlusion. We describe a case of total left main and proximal right coronary artery occlusion and review the clinical and angiographic characteristics of this condition which represents the most severe from of coronary artery disease compatible with life.