Health knowledge made personal
Join this community!
› Share page:
Go
Search posts:

Biochemical diagnosis of ventricular remodelling

Posted May 07 2009 8:29pm

Ventricular remodeling  follows large myocardial infarction .This term denotes to  change in size , shape  and function  of the ventricle   due to altered  myocyte geometry .It is now believed  , this  process begins to occur very early  following a STEMI.(less than 24hours)

lv-remodeling

In which MI remodeling is more common ?

Any MI of large size , especially  anterior  and lateral MI.  Inferior and posterior MI are less affected by adverse remodeling.The incidence is up to 20% of all myocardial infarction ,  if left untreated. Ventricular aneurysm formation and dyskinetic segments can be termed as the worst form of remodeling. The old terminologies of infarct extension and expansion could by synonymous with ventrilar   remodeling . (Note : Every patient with STEMI undergoes some form of physiological remodeling that should not be confused with progressive pathological remodeling , we are discussing  here ! )

What is the clinical impact of remodeling ? How to prevent it ?

Progressive cardiac failure and a  poor outcome .  It may provoke ventricular arrhythmias. ACE inhibitors (CONSENSUS study 1992 )  has since revolutionized  the pharmacological  prevention of adverse remodeling.

How to recognise left ventricular remodeling ?

Many methods are available .

  • 2 D Echocardiography
  • Tissue doppler
  • LV angiogram
  • MRI

These imaging methods diagnose remodeling  only after it manifest* .We know remodeling is a cellular and molecular process .The earliest trigger for remodeling is the mechanical stretch and wall stress on the ventricles.Large areas of necrosed myocardium and  the adjacent normal myocardium sets a perfect stage for eccentric pulling of myocardial segments and unregulated slippage of myocytes.

* Diagnosing fully established  ventricular remodeling  serves ,  no great   purpose as it is very difficult to reverse it by pharmacological methods.it requires complex surgery.

What is the effect of mechanical stretch on cellular function ?

It is well known  myocyte granules secrete Type B  -Naturetic peptide  in response to stretch. It could be a very early sign of adverse remodeling. So monitoring of  BNP may give us an opportunity to intensively treat those patients who are likely to land in progressive cardiac failure.

A baseline level of NT-proBNP >120 pmol/L identified patients  prone for adverse remodeling .Serial measurements showed further increase.It is possible to identify adverse remodeling of LV by documenting fresh elevation of BNP following MI .

Reference :

1 )Nilsson JC, Groenning BA, Nielsen G, et al. Left ventricular remodeling in the first year after acute myocardial infarction and the predictive value of N-terminal pro brain natriuretic peptide. Am Heart J 2002;143:696-702.

2)http://content.nejm.org/cgi/content/full/352/7/666#R24

Post a comment
Write a comment:

Related Searches