What is the incidence of insignificant left main disese ? How will you manage it ?
Posted Mar 05 2009 2:59pm
Left main coronary artery disease (LMCAD) always evokes a terrorising feeling among cardiologists but , to label it as significant, we have a criteria , that is 50% diameter stenosis. So what you do , for a tapering or narrowed left main with 40% stenosis. Isolated insignificant left main is rare *, but real incidence is not known. LMCAD is most often due to , atherosclerosis of left main coronary artery without limiting the flow.
What are the options ?
Leave it alone, with intensive medical management assisted by high dose statin(80mg)
Elective PCI with stenting , even though the lesion is not significant.
*If associated LAD or LCX is there decision making is easier .
How significant is a coronary stenosis ?
The significance of a coronary lesion with reference to “lumen diameter obstruction” is basically flawed. The significance of a coronary stenosis, by tradition is based on it’s hemodynamic impact ,right from the CASS days in early seventies.Unfortunately our mind set has not changed even after realising strongly non obstructive sub critical lesion is more prone for acute coronary syndrome. Is it not ironical to call a 40% lesion a non significant one !
So, the significance of coronary stenosis is two fold.
Hemodyanmic significance
Clinical and pathologic significance
The former predisposes to often chronic stable angina, later likely to result in ACS.
How will you approach a apparently insignificant left main disease ?
A 40 % lesion in left main is hemodynamically not significant , but pathologically very significant.It needs intensive treatment. Plaque passification with medical approach is first choice.If the lesion morphology is eccentric, has irregular margins or involves LAD or LCX ostium doing a PCI or even a CABG is to be considered in spite of the lesion is hemodynamically insignificant .
Why , PCI is considered “not appropriate” for less tighter lesions , even though these lesions have great clinical significance ?
The answer is simple, The risks and the potential cost are more than the benefit !
And further , stents are not innocuous devices either , they always carry a risk of sudden occlusion as like a sub critical lesion !
Left main coronary artery disease (LMCAD) always evokes a terrorising feeling among cardiologists but , to label it as significant, we have a criteria , that is 50% diameter stenosis. So what you do , for a tapering or narrowed left main with 40% stenosis. Isolated insignificant left main is rare *, but real incidence is not known. LMCAD is most often due to , atherosclerosis of left main coronary artery without limiting the flow.
What are the options ?
*If associated LAD or LCX is there decision making is easier .
How significant is a coronary stenosis ?
The significance of a coronary lesion with reference to “lumen diameter obstruction” is basically flawed. The significance of a coronary stenosis, by tradition is based on it’s hemodynamic impact ,right from the CASS days in early seventies.Unfortunately our mind set has not changed even after realising strongly non obstructive sub critical lesion is more prone for acute coronary syndrome. Is it not ironical to call a 40% lesion a non significant one !
So, the significance of coronary stenosis is two fold.
How will you approach a apparently insignificant left main disease ?
A 40 % lesion in left main is hemodynamically not significant , but pathologically very significant.It needs intensive treatment. Plaque passification with medical approach is first choice.If the lesion morphology is eccentric, has irregular margins or involves LAD or LCX ostium doing a PCI or even a CABG is to be considered in spite of the lesion is hemodynamically insignificant .
Why , PCI is considered “not appropriate” for less tighter lesions , even though these lesions have great clinical significance ?
The answer is simple, The risks and the potential cost are more than the benefit !
And further , stents are not innocuous devices either , they always carry a risk of sudden occlusion as like a sub critical lesion !
Suggested reading
Handbook of Left Main Stem Disease
edited by Seung-Jung Park