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Paper text:
a 40yearold male presented with suddenonset severe anterior chest pain , profuse sweating , and vomiting . on admission , his blood pressure was 140/46  mmhg and his heart rate was 77  bpm .
marfan syndrome was diagnosed by ghent criteria.2 electrocardiography revealed nonspecific findings for myocardial injury , except for nonspecific t wave changes ( fig .
transthoracic echocardiography showed severe aortic valve regurgitation , aortic root dilatation , and a dissection flap in the ascending aorta .
his creatinine kinasemb isoenzyme level was mildly elevated ( 5.58  ng / ml ) , but his troponini level was in the normal range ( 0.1  ng / ml ) .
computed tomographic ( ct ) angiography showed that the aortic dissection flaps extended to the aortic sinuses proximally ( fig .
preoperative electrocardiography ( ekg ) and computed tomographic angiography . ( a ) preoprative ekg revealed a nonspecific t wave abnormality without st elevation or pathologic q wave .
( b ) preoperative computed tomographic angiography showed only a deep dissection flap ( black arrow ) in the left aortic sinus at the level of the left coronary artery ( black arrowhead ) .
cardiopulmonary bypass was instituted with a right axillary artery cannula via a side graft and two separate venous cannulas . using moderate hypothermia ,
the aorta was clamped and opened transversely and myocardial protection was maintained with intermittent retrograde blood cardioplegia .
the intima of the right coronary artery was intact , but the intima of the lmca was detached from the ostium .
the proximal dissected portion of the lmca was excised about 6.0  mm and the intact distal portion was anastomosed to a reverse saphenous vein graft of 1.5  cm with 10 simple interrupted 70 polypropylene sutures .
the aortic root , which had thick and shortened aortic leaflets , was replaced with a modified buttonbentall technique3 using a 23mm onx mechanical valve ( onx life technologies , austin , tx , usa ) and a 30mm valsalva graft ( sulzer vascutek , renfrewshire , uk ) .
the proximal end of the vein graft of the lmca was beveled and anastomosed to a low opening in the aortic graft with a continuous 50 polypropylene suture ( fig .
the dissected layers of the right coronary artery button were reapproximated with bioglue ( cryolife , inc . ,
the ascending aorta and the lower portion of the aortic arch were replaced with a beveled 28mm vascutek graft with a side branch during a 32minute period of circulatory arrest with bilateral selective antegrade cerebral perfusion .
after the distal anastomosis was completed , a cerebral perfusion cannula was removed from the left carotid artery and antegrade cardiopulmonary bypass was resumed through the right axillary artery sidegraft cannula and a side branch of the aortic graft .
bypass surgery was performed using a saphenous vein graft to the left anterior descending artery due to concern that there was insufficient flow due to intimal swelling of the reconstructed lmca .
aortic crossclamp time and cardiopulmonary bypass time were 251 minutes and 301 minutes , respectively .
the additional bypass graft to the left anterior descending artery had narrowed , probably due to competition flow .
( a ) reconstruction of the dissected left main coronary artery with severed intima . ( 1 ) the left main coronary artery was trimmed at the healthy intimal portion .
( 2 ) a short reversed saphenous vein graft was anastomosed to the healthy distal portion of the left main coronary artery with 10 simple interrupted 70 polypropylene sutures .
( 3 ) the vein graft was beveled and anastomosed to an opening in the aortic graft .
( b ) six months following surgery , computed tomographic angiography showed the intact lumen of the reconstructed left main coronary artery ( black arrow ) and near closure of the additional saphenous vein graft ( white arrow head ) .
in patients with acute type a aortic dissection , the extension of the dissection into the coronary artery causes coronary malperfusion.4 in patients with acute type a aortic dissection , 6.115% present with coronary malperfusion , which more frequently involves the right coronary artery.1 , 4 , 5 coronary artery dissection with an intact intima can easily be repaired by reapproximating the dissected sinus with bioglue or with teflon felt.6 in cases of coronary intimal detachment , however , bypass surgery is necessary.4 , 5 in patients with acute aortic dissection , left sinus dissection is absent or mild and intimal detachment of the lmca is very rare.7 there are two surgical options for restoring perfusion to the left coronary territory .
the first option is proximal suture closure of the lmca and bypass surgery using two or more grafts to the left coronary artery system.4 , 5 , 6 , 7 this is a simple , commonly used procedure , but it requires two or more grafts . when the distal lmca is nearly intact after the proximal dissected portion is excised , it can be extended with a short reversed saphenous vein graft .
although endtoend anastomosis of the vein graft and the distal lmca can be performed using a continuous suture technique,7 it may be better to use simple interrupted sutures for anastomosing the two obtusely beveled ends to prevent pursestring narrowing of the friable , swollen arterial lumen .
to ensure sufficient perfusion to the left coronary system immediately after surgery , we performed another vein bypass graft from the ascending aortic graft to the left anterior descending artery .
using a short vein graft may also be useful for repairing intimal detachment of the right coronary artery . in this case ,
abstractin patients with acute type a aortic dissection , intimal detachment associated with circumferential dissection of the left main coronary artery ( lmca ) is a rare but lethal complication . 
 we report a marfan patient with dissection and intimal detachment of the lmca that was caused by acute aortic dissection involving the left aortic sinus and that was reconstructed using a short reversed saphenous vein graft . 
 doi : 10.1111/jocs.12746 ( j card surg 2016;31:348350 )