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

Reciprocal changes in 12-lead electrocardiography can predict left main coronary artery lesion in patients with acute myocardial infarction

Acute left main coronary artery (LMCA) occlusion may result in acute myocardial infarction (AMI) or sudden death. ST elevation in the aVR and V1 leads is reported to be valuable in recognizing LMCA occlusion. Early recognition of electrocardiogram (ECG) changes, such as reciprocal ST depression in other leads, is helpful in averting this disaster. This study aimed to determine the reciprocal ST segment depression of 12-lead ECGs associated with acute LMCA occlusion. From January 2000 to December 2004, 61 patients who underwent emergency percutaneous coronary intervention in 3 hospitals due to AMI associated with LMCA (n = 18) and a left anterior descending coronary artery (LADCA) (n = 43) proximal lesion were selected. Reciprocal ST segment depression occurred in leads aVF, V(2), V(3), V(4), V(5), and V(6) with significantly higher incidence in the LMCA group than in the LADCA group. Stepwise linear multivariate discriminant analysis indicated that ST segment depression in leads aVF, V(2), and V(4) could distinguish the LMCA group from the LADCA group. We concluded that reciprocal ST segment depression in leads V(2), V(4), and aVF of a 12-lead ECG is an important predictor of acute LMCA occlusion.

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.

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.