Occluded left main stem coronary artery. Report of five patients and review of published reports

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.

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.

Surgery for Chronic Total Occlusion of the Left Main Stem: A 10-Year Experience

Chronic total occlusion of the left main stem coronary artery is rare. This retrospective study was conducted to evaluate outcomes of coronary artery bypass grafting between June 1998 and June 2008 in patients with chronic left main stem total occlusion. There were 17 (0.025%) cases detected in 67,082 coronary angiograms. The 14 men and 3 women had a mean age of 55.32 ± 9.2 years. Risk factors included diabetes in 8, hypertension in 6, and smoking in 6. Of 54 grafts applied, 15 were arterial and 39 were venous; 14 patients had 3-vessel disease, and 3 had 4-vessel disease. Three patients required intraaortic balloon counterpulsation perioperatively. The mean intensive care unit stay was 2.1 ± 1.2 days, and hospital stay was 7.1 ± 1.5 days. Postoperatively, one patient suffered myocardial infarction, another had a transient ischemic attack with spontaneous recovery, and 2 developed atrial fibrillation. There was no operative or hospital death. Surgical revascularization is considered appropriate treatment for chronic total occlusion of the left main stem.

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.

[Arteriogenesis: a new strategy of therapeutic intervention in chronic arterial disorders. Cellular mechanism and experimental models]

The term arteriogenesis became clarified only some years ago. This endogenous process is a natural compensation mechanism against stenosis or arterial occlusion-induced tissue hypoperfusion via improvement of blood distribution in the pre-existent collateral arteries. The main chronic artery disorders like coronary heart disease, peripheral artery disease and cerebrovascular disease were extensively studied for angiogenesis and arteriogenesis during the last decade. The in vivo animal experiments and the ex vivo analysis of the cellular and molecular mechanisms behind collateral artery development revealed the crucial role of circulating monocytes, endothelial and smooth muscle cells in the remodelling of collateral blood vessels. The adaptive arteriogenesis in the heart, brain and periphery can be stimulated by different chemokines and growth factors. The therapeutic application of these substances resulted in promising data in pre-clinical animal models, i.e. improved collateral conductance, extended neo-vascularization in the collateral dependent tissue regions, decreased infarct area after hemodynamic stroke and better functional parameters in myocardial ischemia. The questions that have to be addressed during the design of human investigations are the optimal delivery approach, the appropriate dosage, timing and the durability of the follow up. The present review tries to give an overview about the main points of the mechanism and the most important experimental data concerning spontaneous and stimulated collateral artery growth, this new and promising therapeutic approach for chronic artery diseases.

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.

Prediction of left main coronary artery obstruction by 12-lead electrocardiography: ST segment deviation in lead V6 greater than or equal to ST segment deviation in lead V1

BACKGROUND

Acute coronary syndrome (ACS) resulting from culprit lesion in left main coronary artery (LMCA) can cause rapid hemodynamic deterioration. It is important to identify these patients early to facilitate timely revascularization. ST segment elevation in aVR greater than or equal to V(1) (aVR-V(1)>or= 0) has been suggested as a sensitive predictor of LMCA disease. As a result of balanced forces, we hypothesized that ST deviation in V(6) greater than or equal to ST deviation in V(1) (V(6)-V(1)>or= 0) might be a good determinant of LMCA disease.

METHODS

We compared admission 12-lead ECGs of ACS resulting from culprit LMCA lesion (n = 75, group I) with ACS resulting from culprit left anterior descending lesion (n = 81, group II). Group I was selected over a period of 10 years. We compared V(6)-V(1)>or= 0 to aVR-V(1)>or= 0 in both groups. We also looked at ratios of ST deviations in V(6),V(1) (V(6)/V(1)>or= 1) and aVR,V(1) (aVR/V(1)>or= 1) in patients where ST segment in V(1) was not isoelectric (group I = 54 and group II = 55).

RESULTS

ST deviation in V(6) was significantly greater in group I as compared to group II (P < 0.001). The reliabilities of V(6)-V(1)>or= 0, V(6)/V(1)>or= 1, aVR-V(1)>or= 0, and aVR/V(1)>or= 1 in predicting LMCA disease were determined.

CONCLUSION

This is the largest series of ECG analysis on ACS resulting from culprit LMCA lesion. V(6)-V(1)>or= 0 and V(6)/V(1)>or= 1 were more sensitive in predicting LMCA as culprit vessel in comparison to previously reported greater ST segment elevation in aVR than V(1).

Coronary pressure measurement to determine treatment strategy for equivocal left main coronary artery lesions

It is often hard to select a treatment strategy for equivocal left main coronary artery (LMCA) disease. We investigated the usefulness of coronary pressure (CP) measurement for determining the treatment strategy in intermediate LMCA disease. We measured CP in 15 consecutive patients with equivocal LMCA disease (age 67.6 +/- 7.5 years, 14 males). Myocardial fractional flow reserve (FFRmyo) was obtained as the ratio of CP distal to the lesion/aortic pressure under maximal coronary dilation. Patients with FFRmyo > or = 0.75 and <0.75 received medical therapy and coronary artery bypass grafting (CABG), respectively, and were followed up for 32.5 +/- 9.7 (20-47) months. Eight patients received medical therapy and 7 patients underwent CABG in accordance with the FFRmyo criteria noted above. FFRmyo of the LMCA was 0.91 +/- 0.01 and 0.61 +/- 0.03 in patients who received medical and surgical therapy, respectively. Neither reference vessel diameter, minimal lumen diameter, nor percent diameter stenosis was significantly different between patients who received medical and surgical therapy. During the follow-up period, no patients with medical therapy showed symptoms due to the LMCA lesion. Similarly, 5 of 7 patients with CABG showed improvement of symptoms and the remaining 2 patients were hospitalized with congestive heart failure. No cardiac death was recorded in the patients with medical or surgical therapy. In conclusion, the present results clearly demonstrated that CP is clinically useful for determining the treatment strategy for equivocal LMCA lesions but coronary angiography is not.

START Trial: a pilot study on STimulation of ARTeriogenesis using subcutaneous application of granulocyte-macrophage colony-stimulating factor as a new treatment for peripheral vascular disease

BACKGROUND

Granulocyte-macrophage colony-stimulating factor (GM-CSF) was recently shown to increase collateral flow index in patients with coronary artery disease. Experimental models showed beneficial effects of GM-CSF on collateral artery growth in the peripheral circulation. Thus, in the present study, we evaluated the effects of GM-CSF in patients with peripheral artery disease.

METHODS AND RESULTS

A double-blinded, randomized, placebo-controlled study was performed in 40 patients with moderate or severe intermittent claudication. Patients were treated with placebo or subcutaneously applied GM-CSF (10 microg/kg) for a period of 14 days (total of 7 injections). GM-CSF treatment led to a strong increase in total white blood cell count and C-reactive protein. Monocyte fraction initially increased but thereafter decreased significantly as compared with baseline. Both the placebo group and the treatment group showed a significant increase in walking distance at day 14 (placebo: 127+/-67 versus 184+/-87 meters, P=0.03, GM-CSF: 126+/-66 versus 189+/-141 meters, P=0.04) and at day 90. Change in walking time, the primary end point of the study, was not different between groups. No change in ankle-brachial index was found on GM-CSF treatment at day 14 or at day 90. Laser Doppler flowmetry measurements showed a significant decrease in microcirculatory flow reserve in the control group (P=0.03) and no change in the GM-CSF group.

CONCLUSIONS

The present study does not support the use of GM-CSF for treatment of patients with moderate or severe intermittent claudication. Issues that need to be addressed are dosing, the selection of patients, and potential differences between GM-CSF effects in the coronary and the peripheral circulation.

Sirolimus-eluting stent implantation for chronic total occlusion of the left main coronary artery

Chronic total occlusion of the left main coronary artery (LMCA) is rare. Recently, percutaneous coronary intervention has been increasingly applied to unprotected LMCA lesions. We describe a patient with chronic total occlusion of the LMCA who was successfully treated with bifurcation stenting with sirolimus-eluting stents.

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.

Importance of wall motion analysis in the diagnosis of left main disease using stress nuclear myocardial perfusion imaging

We describe a case of a 54-year-old male who underwent exercise technetium-99m sestamibi myocardial perfusion imaging prior to his renal transplantation. With exercise, the patient's myocardial perfusion imaging did not show any transient or fixed myocardial perfusion abnormalities due to balanced ischemia. However, wall motion analysis showed a new global left ventricular systolic dysfunction on post-exercise images. Coronary angiography showed severe left main coronary lesion involving ostia of left anterior descending, ramus intermedius and left circumflex coronary arteries with moderate right coronary artery disease. If one had used the perfusion imaging alone in this patient, the severe multivessel disease including left main coronary disease could have been missed. In this article we emphasize the importance of wall motion analysis in patients undergoing myocardial perfusion imaging.

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V(1)

OBJECTIVES

We sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction.

BACKGROUND

Prediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis.

METHODS

We studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group).

RESULTS

Lead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 +/- 0.13 mV) than in the LAD group (0.04 +/- 0.10 mV). Lead V(1) ST segment elevation was lower in the LMCA group (0.00 +/- 0.21 mV) than in the LAD group (0.14 +/- 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V(1) ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation.

CONCLUSIONS

Lead aVR ST segment elevation with less ST segment elevation in lead V(1) is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient's clinical outcome.

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

Total occlusion of the left main coronary artery is rare. Acute occlusion is invariably fatal; however, survival is possible if the patient reaches the hospital in time. Patients usually present with acute myocardial infarction, cardiogenic shock, and sudden cardiac death. Chronic total occlusion presents with angina, myocardial infarction, or congestive heart failure. The authors describe complete occlusion of the left main coronary artery in a patient who presented with recent-onset angina. They review the clinical and angiographic features of 60 cases described in the literature.

[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. After reviewing the coronary angiographies performed in our laboratory between 1986 to 1995, we found a prevalence of 0.04%. These patients presented unspecific symptoms similar to other kinds of coronary artery disease. In all cases, the right coronary artery was dominant with extensive collateral circulation to the left coronary artery. Ventricular function was normal in 50% of the cases. Probably, in these unusual cases, the best therapeutic approach is surgical revascularization.

[Direct dilatation and emergency bypass operation of main branch occlusion in acute anterior wall infarct and cardiogenic shock]

Occlusion of the left main coronary artery (LMCA) is the cause of myocardial infarction in about 0.04%. Those patients who do not die during the acute phase often do have a dominant right coronary artery with extensive collaterals to the left coronary artery. Because this is a very rare situation there are only some cases reports dealing with the management of these patients. A 60 years old woman was admitted to our hospital with the signs of an acute Q-wave anterior myocardial infarction. Within a few minutes after the arrival she developed a cardiogenic shock. Coronary angiography was performed immediately. The left main coronary artery was occluded and a big right coronary artery showed a significant stenosis. There were many collaterals from the right coronary artery supplying the left coronary artery. After information of the cardiac surgeons, primary angioplasty of the LMCA was performed in order to achieve hemodynamic stabilisation and to relieve symptoms. Reperfusion of the left anterior descendent coronary artery (LAD) could be achieved within 30 minutes. This led to hemodynamic stabilisation of the patient. But a significant residual stenosis of the LMCA remained and the circumflex artery was still occluded. In the meanwhile cardiac surgery was able to be performed and so the patient was transferred to surgery without further dilatation or stent implantation. Four venous grafts (LAD, first diagonal branch, circumflex artery and right coronary artery) were inserted. After 4 weeks the patient was in a good shape and could be discharged at home. Primary angioplasty seems to be an effective treatment in patients with acute myocardial infarction and an occlusion of the LMCA. But coronary bypass surgery is nearly almost necessary during the following period in order to achieve complete revascularisation and to improve survival.

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.

Nineteen years survival after occlusion of the left main coronary artery by virtue of an anomalous septal branch

This case presents a patient who survived 19 years with an occluded left main coronary artery as a result of collateral flow to the anterior wall from an anomalous septal branch arising from the right coronary artery. The case illustrates that minor variations in coronary anatomy may have important effects on the prognosis of a patient.

Acute occlusion of left main coronary artery without ventricular damage

We report a patient with acute occlusion of left main coronary artery with only a small increase of cardiac enzymes but without electrocardiographic signs of acute myocardial infarction. Normal global and regional left ventricular function could be documented angiographically. Damage of myocardium was prevented by extensive collateral circulation from a large dominant right coronary artery.

Survival after myocardial infarction caused by acute left main coronary artery occlusion: case report and review of the literature

We report a 44-year-old white male presenting with an acute anterior myocardial infarction. Cardiac catheterization at 2 weeks postinfarction revealed total occlusion of the left main coronary artery. There was a normal dominant right coronary artery supplying moderate collaterals to the left coronary system. The patient was managed with conservative therapy and was N.Y.H.A. functional class II on followup 2 years later. A review of the literature relative to myocardial infarction caused by acute left main coronary artery occlusion is presented, and unique features of these cases are described.

Complete occlusion of the left main coronary artery: clinical and angiographic observations in five cases

Involvement of the left main coronary artery is observed in approximately 5 to 8% of patients with coronary artery lesions detected by coronary angiography, but occlusion of the left main artery is a very infrequent finding. Out of approximately 4000 patients undergoing coronary angiography, four men and one woman, 37 to 60 years old, showed total occlusion of this vessel. Four of them had angina pectoris and three had had a myocardial infarction. All five showed deep ST depression in V 2(or 3)-6 during bicycle exercise testing. Apart from the left main artery occlusion, all had significant obstructive lesions in other coronary vessels, including the right coronary artery or its major branches. There was collateral circulation from the right coronary artery in all patients. Left ventricular function was well preserved in three patients and markedly impaired in two. Four patients underwent bypass surgery and they have been followed for 10 to 28 months. Three are free of angina and one has only minimal angina. One patient refused surgery and he continued to have severe angina despite intense medical treatment. He died suddenly after 30 months follow-up. In patients with complete occlusion of the left main coronary artery, development of adequate collateral flow seems important in preserving left ventricular function, but collaterals are usually insufficient to prevent angina. Moreover, associated obstructive lesions in other coronary arteries constitute a potential threat to the collateral circulation. Effective symptomatic relief is obtained by coronary bypass grafting, and revascularization may also improve prognosis in this subset of patients with coronary heart disease.

Total obstruction of the left main coronary artery

A rare and often fatal condition, total obstruction of the left main coronary artery has been treated with increasing success in both acute and chronic clinical settings. Seventeen patients with acute occlusion have been reported in the literature. All were discovered at the time of acute periinfarction catheterization and were treated aggressively with intracoronary thrombolysis, percutaneous transluminal angioplasty, emergency bypass surgery, or a combination of techniques. Chronic total occlusion of the left main coronary artery has been reported in 59 patients, including 3 at our institution. These patients present with chronic but increasingly severe angina. A right dominant coronary anatomy is always found, usually with well-developed right-to-left collaterals. The results of surgical revascularization in our 3 patients and in 45 others described in the literature support the safety and efficacy of this approach.

Spasm of the left main coronary artery: an indication for surgery?

A patient with severe angina at rest was studied by coronary angiography. A severe spasm in the left main coronary artery was observed; after nifedipine and isosorbide dinitrate a moderate stenosis was still present and surgery was successfully performed.