Dr.S.Venkatesan MD

We essentially live in our blood vessels and age in our arteries.CAD is the principal  cardio vascular disease, which  God has created in Homo-sapiens to ensure they  do not stay more than “allotted life span” in this planet. Of course , the current generation cardiologists equipped with scientific weapons , have since decided to take the fight directly in the Almighty’s domain .Contrary to the popular medical doctrine, treating an established CAD seems to be easier task than preventing a new onset CAD.

While , arteriosclerosis is a normal aging process, atherosclerosis could be an  aging as well as a distinctive pathological process. However , athero-thrombosis  is a definite pathology of vessel wall .We know at any time atherosclerosis  can transform into  athero-thrombosis  and result in  clinical event depending upon the  triggers and other associated conditions, which we refer to as major or minor  risk factors.

In scientific terms ,

• Primary prevention  of CAD is preventing first episode of  Coronary  event*(Typically , CSA, STEMI/UA,NSTEMI/SCD,)
• Secondary prevention  is  prevention  of  second  or subsequent episodes following the first clinical event.(*What if , if  the first event is silent and never known ? )

For all practical  purposes CAD and  coronary atherosclerosis is synonymous. Can we  prevent atherosclerosis in human biological system ?  What are we  supposed to refer to  such a preventive measure , if any ?

We are biased towards obstructive CAD as we often  think it is the  the only form of CAD .Then , how do we diagnose , treat and prevent a minimal non flow limiting plaque , coronary endothelial dysfunction , or  acute coronary erosion that can occur in very early stages of atherosclerosis, in other wise healthy persons.(Routine IVUS ,OCT ? Futile isn’t )

• Preventing  sub-clinical  CAD  from manifesting  as clinical CAD , is technically   primary prevention”  but still  patho-biologically  secondary prevention.
• Preventing a CAD in a patient  with peripheral vascular  disease  or preventing CAD in a patient with TIA or stroke is secondary prevention for cerebrovascular disease but  falls within the definition  of primary prevention of  CAD.
• Then  comes the new semantics :Primordial prevention .This could be same as primary (or another  version of primary prevention ).Primordial prevention is preventing development  the risk factor  itself (Like DM,HT, Dyslipidemia )

So ,whenever , we talk about primary prevention of CAD by Aspirin or Statins ,realize the complexities involved .Before i finish, let me make you  dizzy further with this quixotic one . In a multivessel CAD, as the  atherosclerotic  plaques are scattered across the coronary arteries in various stages of  maturity  , long term Aspirin  following  anterior STEMI has to secondary prevent an event  in LAD territory  . . . but   primary prevent a plaque disruption in RCA territory !

Reference

1.USPSTF Guidelines : Aspirin for the Prevention of Cardiovascular Disease: Preventive Medication