Chronic/subacute total occlusion of the left main coronary artery--a case report and review of literature

Chronic Total Occlusion of the Left Main Coronary Artery With Preserved Left Ventricular Systolic Function Presenting as a Chronic Coronary Syndrome: A Case Report and Brief Review

The incidence of lesions involving the left main coronary artery (LMCA) during coronary angiography is approximately 5% to 8%. It usually presents with acute coronary syndrome and can be fatal. Total occlusion of the LMCA is rare, often accompanied by myocardial infarction and cardiogenic shock. We present an LMCA chronic total occlusion case in a 60-year-old female patient with chronic coronary syndrome. In our case, the LMCA was selectively visualized, and it was found to be occluded. The right coronary artery fed the entire left system through the collateral network. The patient had no risk of coronary artery disease other than hypertension. Successful coronary artery bypass grafting was performed without any complications.

Unexpected normal left ventricular systolic function after total chronic occlusion of left main coronary artery and stenosis of right coronary artery: a case report and review of the literature

INTRODUCTION

Total occlusion of the left main coronary artery is a very rare finding in coronary angiography because of its highly lethal nature. Right coronary artery dominance and extensive collateral circulation are the principal determinant factors of survival after total occlusion of the left main coronary artery. The impact on the left ventricle is often significant with a profound alteration of its systolic function.

CASE PRESENTATION

We describe a 52-year-old North African man, a tobacco smoker, who presented symptoms of unstable angina related to a total chronic occlusion of his left main coronary artery with a right coronary artery stenosis. Unexpectedly, the impact on his left ventricle was absent with normal dimensions and systolic function. He underwent a successful on-pump coronary artery bypass grafting with uneventful postoperative course and good recovery.

CONCLUSIONS

Total occlusion of the left main coronary artery is a rare condition, the fact that the left ventricle retains a normal size and systolic function makes it exceptional, which must be kept in mind to avoid dangerous examinations and delayed treatment. Coronary artery bypass surgery should be considered the main treatment of total chronic occlusion of the left main coronary artery.

Successful treatment of a nonagenarian patient with acute coronary syndrome complicated with chronic total occlusion of the left main coronary artery

Although chronic total occlusion of the left main coronary artery (LMCA) is considered very rare, this condition could be fatal if it becomes complicated with an acute coronary syndrome lesion in the right coronary artery (RCA) which is usually the only remaining coronary artery for the myocardium. We reported a successfully treated case of a nonagenarian patient with ST-segment elevation myocardial infarction, who had subtotal occlusion of the RCA and total occlusion of the LMCA with Rentrop grade 2 collateral coronary artery supply from the RCA.

Left main coronary artery compression in pulmonary arterial hypertension

In patients with pulmonary arterial hypertension (PAH), chest pain is most likely due to right ventricular demand ischemia. We report a patient with idiopathic PAH who developed severe angina due to extrinsic compression of the left main coronary artery (LMCA) from a dilated pulmonary artery trunk. The diagnosis was verified by electrocardiogram after exercise, coronary angiography including intravascular ultrasound, and cardiac multidetector computed tomography (MDCT). The origin of the LMCA was high in the left coronary sinus, facilitating extrinsic compression. The patient was successfully treated by percutaneous coronary intervention with stent implantation in the LMCA. Extrinsic compression of the LMCA is a severe and potentially fatal complication that should be considered in all patients with PAH and angina. MDCT is the method of choice for first-line diagnosis.

Surgery for chronic total occlusion of the left main coronary artery

BACKGROUND AND OBJECTIVES

Chronic total occlusion of the left main coronary artery (LMCA) is a rare condition, and the information on surgical experiences is limited. Although total occlusion of the LMCA is accompanied by well-developed collateral circulation, the condition of circulation is unstable during manipulation of the heart. We report our experience with revascularization in cases with total occlusion of the LMCA using the on-pump beating-heart (OnP-BH) technique.

DESIGN AND SETTING

Retrospective case review of patients treated at The First Affiliated Hospital of China Medical University over a 10-year period (1999 to 2009).

PATIENTS AND METHODS

The on-pump coronary artery bypass grafting with the beating heart was applied to 8 patients with chronic total occlusion of the LMCA. The extracorporeal circulation period, intubation duration, intensive care unit stay period, discharge period, preoperative and postoperative treatments, and follow-up were observed.

RESULTS

The mean extracorporeal circulation period was 80.4 (19.7) minutes. The mean intubation duration was 13.0 (4.6) hours. The mean intensive care unit stay period was 3.2 (0.7) days, and the mean discharge period was 16.8 (3.3) days. No perioperative myocardial infarction occurred. The mean follow-up period was 50.9 (34.8) months. All patients were asymptomatic, and no deaths were recorded during the follow-up period. The results of echocardiography showed improvement in the left ventricular function.

CONCLUSIONS

The OnP-BH myocardial revascularization seems to be a valid alternative for chronic total occlusion of the LMCA.

Chronic Effort-Induced Angina as Presentation of a Totally Occluded Left Main Coronary Artery: A Case Report and Review

In this report, the case of a 40-year-old patient with chronic total occlusion of the left main coronary artery is discussed. Total occlusion of the left main coronary artery is a rare finding at coronary angiography. When present, patients most often have extensive collateral circulation from the right coronary artery. The mainstay of treatment is surgical with coronary artery bypass grafting.

High mortality after coronary bypass surgery in patients with high-grade left main coronary artery stenosis

OBJECTIVE

To determine mortality after coronary artery bypass grafting (CABG) in relation to degree of left main coronary artery (LMCA) obstruction.

DESIGN

All patients without LMCA stenosis (n=3370), with low-grade stenosis (n = 261), high-grade stenosis (n = 224) or total occlusion of the LMCA (n = 15) were followed for ten years after CABG performed during 1970-1989.

RESULTS

Early mortality was 1.9% and 2.3%, respectively, if there was no or a low-grade LMCA stenosis vs. 6.3% if the stenosis was high-grade. Ten-year survival was 76% if no LMCA obstruction, 74% if low-grade stenosis and 64% if the stenosis was high-grade. Risk of early death (odds ratio 2.6, 95% CI 1.4-4.8) and mortality at ten years (relative risk 1.5, 95% CI 1.1-2.0) was higher in patients with high-grade stenosis than in those without LMCA stenosis. There was no increased long-term mortality in patients with low-grade stenosis or among the few patients with occlusion of the LMCA.

CONCLUSIONS

High-grade LMCA stenosis was associated with a three-fold increased risk of early and fifty percent higher risk of late death than in patients without LMCA stenosis.