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

Twelve-year trends in unprotected left main coronary artery occlusion: insights from a real-world multicentre study

AIMS

Acute myocardial infarction (AMI) resulting from unprotected left main coronary artery (LMCA) occlusion and subtotal occlusion is a life-threatening condition. Although AMI management has improved in the past two decades, there is limited information on recent trends in patient characteristics, management, and outcomes for acute unprotected LMCA-related AMI. This study aims to assess such trends over a 12 year period.

METHODS AND RESULTS

This retrospective multicentre study includes patients with unprotected LMCA occlusion/subtotal occlusion admitted to three tertiary hospitals between 2008 and 2020. The patients were divided into two groups based on the chronology of presentation: a 'past group' (January 2008 to December 2014) and a 'contemporary group' (January 2015 to December 2020). The study compares clinical characteristics, management approaches, and outcomes between the two groups. The study includes 128 patients, with 51 (40%) in the 'past group' and 77 (60%) in the 'contemporary group'. Baseline risk factors did not show statistically significant differences between the two groups, except for hypertension (49% vs. 74%; P = 0.005). Chest pain was more frequent in the 'past group' (98% vs. 89%; P = 0.014), and a trend towards more cardiac arrests was observed in the 'contemporary group' (18% vs. 31%; P = 0.087). Revascularization type did not differ significantly (P = 0.419), but manual thrombectomy was less frequently used (41% vs. 23%; P = 0.032) and stent implantation showed a trend towards higher rates (66% vs. 78%; P = 0.150) in the 'contemporary cohort'. There was a gradual shift from bare-metal to drug-eluting stents, with a significantly higher percentage of ticagrelor/prasugrel loading in the 'contemporary cohort' (5% vs. 79%; P < 0.001). The use of mechanical circulatory support (MCS), although not statistically significant, was higher among patients in the 'past group' (67% vs. 51%; P = 0.073). The type of MCS differed significantly between groups, with a decrease in intra-aortic balloon pump use (67% vs. 42%; P = 0.005) and an increase in veno-arterial extracorporeal membrane oxygenation (4% vs. 22%; P = 0.005) and Impella system (0% vs. 3%) over time. Survival analysis showed no significant differences (P = 0.599; log-rank test) in all-cause mortality between the different time groups, with the long-term survival rate being approximately 30%.

CONCLUSIONS

In our real-world population, despite the progressive use of newer drugs and more advanced devices over time, patients with unprotected LMCA occlusion/subtotal occlusion remain a subpopulation with poor prognosis.

Electrocardiographic characteristics associated with in-hospital outcome in patients with left main acute coronary syndrome: For contriving a new risk stratification score

AIM

The aim of this study was to evaluate electrocardiographic characteristics associated with in-hospital prognosis in patients with left main acute coronary syndrome.

METHODS AND RESULTS

A total of 89 left main acute coronary syndrome subjects were selected from 3357 consecutive acute coronary syndrome patients (2.7%). Patients of this study were divided into two groups; those who survived and those who died. Patients' characteristics and electrocardiogram on admission were then retrospectively analyzed between the two groups. In-hospital mortality was 28.1%. The prevalence and degree of ST-segment elevation at lead aVL were significantly higher in the deceased group than in the survival group ( p<0.001). However, those at lead aVR did not show significant differences between the two groups. Moreover, the width of the QRS-complex was significantly wider (lead V3; p<0.001), and the level of five minus the absolute value of five minus number of ST-segment elevation (5-|5-ST|; due to the highest in-hospital mortality (70%) in the five-lead ST-segment elevation group) was significantly larger in the deceased group than in the survival group ( p<0.001). The odds ratios that predicted in-hospital cardiac death were 1.03 for width of the QRS-complex at lead V3 (95% confidence interval (CI); 1.01-1.06; p=0.003), 1.74 for 5-|5-ST| (95% CI; 1.03-3.00; p=0.040), and 1.44 for ST-segment elevation at lead aVL (95% CI; 0.93-2.23; p=0.100).

CONCLUSIONS

ST-segment elevation at lead aVL rather than aVR, width of the QRS-complex at lead V3 and number of ST-segment elevation were the prognostic predictors for in-hospital mortality in patients with left main acute coronary syndrome. Electrocardiographic characteristics should be assessed in addition to the established risk score in patients with left main acute coronary syndrome.

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.

Factors predicting mortality in patients after myocardial infarction caused by left main coronary artery occlusion: significance of ST segment elevation in both aVR and aVL leads

Acute left main coronary artery obstruction is rare and most patients in this clinical setting die of sudden death or cardiogenic shock. During the past 8 years, we encountered 13 patients with acute myocardial infarction caused by total occlusion of the left main coronary artery (LMCA-AMI). Thus, we surveyed these patients, and attempted to elucidate helpful predictors related to the prognosis. Six of 13 patients with LMCA-AMI survived. Successful left coronary artery dilatation was achieved in all survivors (group S), and in 5 (71%) non-survivors (group non-S). The age was not different between the two groups. A past history of angina was confirmed in 83% of group S. while only in 29% of group non-S. Clinical findings such as time of onset of AMI, interval from the AMI onset to admission, elapsed period from the AMI onset to recanalization of LMCA and the value of CK on admission were not different between the two groups. However, cardiogenic shock occurred in only 1 patient (17%) in group S compared with 5 patients (71%) in group non-S. As emphasized in the literature, good collateral circulation to the left anterior descending artery was observed in 5 patients (83%) in group S, while not observed in group non-S. Electro cardiographically, ST elevation in the aVR lead was very characteristic. This finding was confirmed in 69% of the total patients. Noticeably, 5 out of 6 non-survivors (83%) showed ST elevation not only in leads aVR but also in the aVL lead. In addition to the absence of collateral circulation, this electrocardiographic finding, which obviously indicates the presence of extensive myocardial ischemia in the diseased heart, is a simple and important predictor suggesting a poor prognosis in LMCA-AMI patients.

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.

Survival using percutaneous cardiopulmonary support after acute myocardial infarction due to occlusion of the left main coronary artery--a report of two cases

Two cases of acute myocardial infarction due to an occlusion of the left main coronary artery (LMCA) are presented. Their cardiogenic shock was successfully treated with percutaneous cardiopulmonary support (PCPS), in addition to reperfusion therapy and an intraaortic balloon pump. The 2 patients were able to be weaned from PCPS and discharged from hospital. It is suggested that the early use of PCPS may be life-saving in patients with myocardial infarction due to the occlusion of the LMCA who have progressed to cardiogenic shock.

[Occlusion of the left main coronary artery with silent ischemia and syncope]

Mortality in the total occlusion of the left main coronary artery is very high, and the few cases who lived reported were very ill and symptomatic patients. We present a case with angiographic documentation of total occlusion of the left main coronary artery in a patient without angina and with a normal rest electrocardiogram in which a syncope was the only symptom. Severe isolated silent ischemia was induced during an exercise test. Total occlusion of the left main coronary artery associated to silent myocardial ischemia without cardiac failure has never been previously reported.

[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.

Survival following cardiogenic shock caused by acute left main coronary artery total occlusion. A case report and review of the literature

The authors describe a fifty-five-year-old Japanese man with an acute extensive anterior myocardial infarction associated with a total occlusion of the left main coronary artery. The patient suffered cardiogenic shock and was treated successfully with rescue percutaneous transluminal coronary angioplasty and an intraaortic balloon pump (IABP) after unsuccessful intracoronary thrombolysis. Ten days after admission, he was weaned from IABP, and recovery-phase coronary angiography revealed no significant coronary artery stenosis and an ejection fraction of 32% by left ventriculography. The patient was discharged from the hospital without any ischemic findings.

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.

Survival from acute occlusion of the left main coronary artery with preexisting collateral vessels--a case report

A thirty-two-year-old man suffered from evolving acute myocardial infarction caused by total occlusion of the left main coronary artery, which was 95% stenosed before the onset. Nevertheless, he had a good clinical course. The myocardium may have been protected by well-developed preexisting collateral vessels as evidenced by serial coronary angiograms.

Total left main coronary artery occlusion after aortic aneurysm repair and valve replacement

A 38-year-old woman with complete occlusion of the left main coronary artery secondary to cannulation during aortic valve replacement is presented. The clinical course was characterized by progressive left ventricular dysfunction and congestive heart failure. Recognition of this potential problem when it occurs is important as to institute therapeutic measures which may interrupt a patient's progressive clinical deterioration.

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.