Abrupt left coronary artery malperfusion secondary to acute type A aortic dissection after weaning from cardiopulmonary bypass: a case report.

INTRODUCTION

Acute Stanford type A aortic dissection (ATAAD) is a lethal emergency. However, even with instant surgical repair, early mortality is up to 20%. ATAAD complicated by coronary artery involvement is considered rare but life-threatening because this can cause coronary artery malperfusion which results in acute myocardial infarction. In particular, left coronary artery malperfusion can bring worse outcomes than right coronary artery malperfusion, but there are few reports of left coronary artery involvement secondary to ATAAD.

CASE PRESENTATION

We present a case of a woman who got emergency open heart surgery due to ATAAD. After the hemiarch replacement, the first weaning from bypass was relatively smooth. However, as soon as starting infusion protamine, we found out sudden regional wall motion abnormality at the diffuse anteroseptal to the lateral wall on echocardiography and ST depression on leads II and V5 electrocardiogram after several ventricular fibrillation. We recognized by echocardiography that intimal dissection flap extended to the left coronary artery ostium and dynamically obstructed left coronary artery blood flow, because the true lumen collapsed dynamically during the diastolic phase. Upon re-establishing bypass, proximal aortic false lumen was obliterated with BioGlue again. Smooth weaning from bypass proceeded at last. Finally, the blood flow to the left coronary artery ostium was good, and the wall motion abnormality was improved.

CONCLUSION

Our report suggests the importance of the degree of myocardial damage caused by coronary artery malperfusion which is a major predictor of patient outcome. To reduce complications and minimize the mortality rate, an instant treatment plan is needed. However, limited options for exact surgical treatment directions or guidelines for coronary artery malperfusion secondary to ATAAD are available so far. We emphasize that we should not neglect any signs indicative of coronary artery malperfusion appear such as changes of electrocardiogram and echocardiography. Moreover, our report contributes to a profound understanding among clinicians regarding the necessity of practical treatment guidelines about coronary artery malperfusion due to ATAAD based on various surgical experiences and studies.