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Posts Tagged ‘evidence based cardiology’

Who is an “Interventional cardiologist” ?

Posted in bio ethics, cardiology- coronary care, Cardiology-Coronary artery disese, tagged , , , , , , , , , , , , , , , , on August 7, 2009| Leave a Comment »

cardiologist Is he a person who puts  a   metal coil  coated with a synthetic fungus   in  a   incidentally  detected  block  inside a  small coronary artery and sends the bill to the Insurance company ?

Is he a person in a  cosmopolitan  hospital  who opens up a    chronically   closed  coronary artery , in an asymptomatic patient  and  live telecasts  his achievement trans continentally ?

Is he a person who   checks in by  the early morning flight and  puts multiple wires in  an  aged   patient   with  class 3 heart failure and  make  him walk  20 meters extra at a cost of  1000$ / Meter ?

Is he a person living in   Wall   street  ,   who   looks  for variety of holes In  the heart and trying to occlude  it  with   exotic   devicespci ptca stent

Is he the unknown   physician   who Intervenes in the natural history of Rheumatic heart disease   and arrests   immune mediated   valve damage by giving the  monthly injections  penicillin in remote parts of our country ?

Is he the person   who   Intervenes to prevent young   persons   from  smoking and help maintain  their  coronary endothelium  enriched with nitric oxide  & arrest  the coronary epidemic ?

cardiologist 2

Is he the small town doctor  who  Intervenes  to treat a breathless cardiac failure patient  with  digoxin and frusemide  and  dramatically alleviate the  symptoms and  prolong the  life of our poor country men?

Is she the village health nurse from an inaccessible health  centre  located in a  hilly terrain ,  Intervening  successfully, by   pulling out  live babies  from  severely anemic pregnant  mothers with failing hearts ?

pci ptca cardiologist coronary angiograms

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Ignorance based cardiology :How often a coronary artery reject a stent ?

Posted in Cardiology -unresolved questions, cardiology- coronary care, Cardiology-Coronary artery disese, Infrequently asked questions in cardiology (iFAQs), tagged , , , , , , , , , , , , , , on August 5, 2009| 9 Comments »

Fundamental principle  of  human biological system is to live in harmony with nature and environment.Each cell  has a unique reaction  when it comes into contact with  external  material. This reaction can be acute or chronic  ,   local or systemic. The most severe form of allergy is called anaphylaxis  that can result in instantaneous loss of life. There  is a whole gamut of disorders  that  resulted  in a  separate  speciality called allergic medicine .

Further ,the transplantation  science have   taught us  an  organ or cell can be rejected at any point of time after implantation (Hyperacute -chronic) .With advancement of science we have started implanting a variety of devices  with complex metallurgy ,inside human body, metal clips, prosthesis, valves, wires, etc .How the body handles them .The consequences can be a mild reaction to major ones occasionally.

Consider ,a local allergy due to a orthopedic prosthesis  in one of the leg bones  is far less serious than a metal within a coronary artery  irritating the intima .

Remember hypersensitivity reactions can be severe . This lady reacted  like this to a sandal slipper -A  fiery red  infiltration

contact dermatits stent allergy pci coronary

Imagine  if a stented coronary artery react like this what would be the possible consequence ?

In susceptible  individuals  , can a metal cause

  • Intimal hyperemia
  • Intimal induration
  • Intimo-medial edema  following stent deployment

pci stent coronary angiogram thrombosis des

Why drug eluting stents are more prone for hypersensitivity ?

The answer is simple , while metal allergy is a comparatively rare phenomenon, the drugs we  coat and the polymers used are  many fold likely to result in hypersensitivity reaction.

While  the world is worried  more  about penicillin , sulpha allergy which occurs in 1 in 100000 ,  we tend to ignore the metal and drug  reactions within  the tender coronary arteries.

stent des rejection virmani pci

What is  the clinical expression of  stent hypersensitivity ?

It is  often a coronary event in the acute phase and restenosis in chronic phase.

How much of acute stent thrombosis is related to stent allergy mediated reaction ?

The exact incidence  will  never be known. It could be high. Whenever a sudden unexpected early stent occlusion can be a suspect .

Is stent allergy a local reaction or systemic reaction ?

It is most often local .The drugs the stent elute can elicit a systemic reaction occasionally.

So what can be done to prevent this complication ?

Drug companies in it’s  package regularly  include the warning  message ! What does it imply to have a caution  on the covers ? .This warning simply represent about our ignorance in this issue. We presume it is a minor problem.

pci stent thrombosis stent allergy metal

Questions unanswered

  1. How does a cardiac patient knows whether he is hypersensitive to stainless steel or nickel ?
  2. Is it practical to have a stent allergic test in every patient before PCI ?
  3. Is routine administration of corticosteroids for few days after PCI an answer ?

Reference

R.Virmani , circulation 2004

http://circ.ahajournals.org/cgi/content/full/109/6/701?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=stent+%27allergy%22+&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT

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Critical cardiology : And now , drug abuse inside human coronary arteries !

Posted in Uncategorized, tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , on January 18, 2009| Leave a Comment »

                                                    Drugs are poisons , whenever it is administered without valid purpose. it can enter human body  in many ways (Oral, intravenous, percutaneous etc ) And now we have another route namely intracoronary !

                                                   In quest for prevention of restenosis, many of the anti cancer drugs are now delivered directly inside the coronary arteries .These drugs are secreted  like a sustained release  tablet from the drug coated stents.These drugs are expected to prevent restenosis within the stented segment.But, after years of  intense debate and research  , we realised that ,  drugs  eluted from the stent  could damage the distal coronary vascular bed and coronary microcirculation.( And thus came the epidemic of acute stent thrombosis ! )

                                                The tender and sensitive coronary microvasculature  is constantly exposed to  these  powerful anticancer and immmunosuppresive  drugs .It is a great surprise , no body thought of  this dangerous drug -coronary artery interaction ! It required the genius of Renu virmani and others to point out this.

But still , the cardiology community by and large , fails to consider  this an important issue.This is proven by the fact, usage of DES is  still increasing  and used mainly as an off label indication.

Read this land mark article from circulation

picture1

http://circ.ahajournals.org/cgi/content/full/115/8/1051?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=1&author1=renu+virmani&andorexacttitle=and&andorexacttitleabs=and&andorexactfulltext=and&searchid=1&FIRSTINDEX=0&sortspec=relevance&fdate=1/1/2007&tdate=12/31/2007&resourcetype=HWCIT

 

Questions that need to be answered

  • What is the long term effects of drugging a coronary artery ?
  • Is no reflow or slow flow  more common after DES , because of the adverse drug reaction in the distal vascular bed ?
  • If a patient  with  DES  undergoes a CABG later what  would be  the impact of the  drug on the graft ? Will the functional vasodilatation   affected ?

Final message

                                  A drug , to get a legal clearance it has to undergo  hundreds of rigorous tests . Finally it is cleared for that  specific indication for which it is tested  .Just because a drug is cleared for one purpose ( Paclitaxel for malignancy ) it does not mean it is safe to use for any other  purpose for which it is deemed to be useful . Exactly the  opposite is happening   in the  the field of interventional cardiology . No body wondered to think what would be the effect of these drugs on the normal coronary endothelial cells and vasculature.Is it not a crime ,  without analysing this particular issue  , dozens of drug eluting stents have been released in the market . And now,  sounds of crying  foul is heard world wide !

Let us thank  , the so called negative forces in cardiology  for making this an  issue . In science ,  the watch dogs should bark  at  times of danger not wag the tail !

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The art of unlearning cardiology : ACC/AHA 2009 revascularisation guidelines -It is 135 pages of simple commonsense !

Posted in bio ethics, Cardiology - Clinical, cardiology -Therapeutics, cardiology- coronary care, tagged , , , , , , , , , on January 16, 2009| Leave a Comment »

Contrary to popular belief ,great things happen only rarely in medicine . It takes  only  few  months of  training  or  workshops ,  for a  wrong or inappropriate concept  to  percolate  our  brains !  But , it  would require,   decades  of  time , energy  and  efforts  ,  for  correcting  that  wrongly  assimilated concept  in medicine !

Interventional cardiologists are  among the  rare breed of physicians,   who always believe in evidence !  But ,  the quality of  the  evidence  is rarely questioned  !  30 years of PCI  & 20 years of stenting has failed  our  common senses ! Fortunately , today,  we have 135 pages of new evidence ( Not really new , old evidence interpreted with  sound logic !)

Hats off to ACC and associates for bringing out this much belated appropriateness guidelines for the interventional cardiologists.

ACCF/SCAI/STS/AATS/AHA/ASNC 2009 Appropriateness Criteria for Coronary Revascularization

A Report of the American College of Cardiology Foundation Appropriateness

Criteria Task Force, Society for Cardiovascular Angiography and Interventions,

Society of Thoracic Surgeons, American Association for Thoracic Surgery,

American Heart Association, and the American Society of Nuclear Cardiology

Endorsed by the American Society of Echocardiography, the Heart Failure Society of America, and the

Society of Cardiovascular Computed Tomography

Click here to get guidelines

http://circ.ahajournals.org/cgi/reprint/CIRCULATIONAHA.108.191768v1.pdf

If you don’t have time to read the entire document (135 pages  )

Just remember only one point

Common sense,  more  often  prevails  over  evidence ,  in medicine . Apply it  , frequently  in your patients .They will reep the benefits !

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Drug eluting stents : A slap on the face of Evidence based cardiology . . .

Posted in bio ethics, Cardiology -Interventional -PCI, cardiology- coronary care, tagged , , , , , , , , , , on January 1, 2009| Leave a Comment »

Drug eluting stents : A slap on the face of Evidence based cardiology . . .

Click the BMJ link or read below

 

venkat-bmj

It is often said science is sacred and unfortunately we forget ,  science is not a heavenly creation and it is the creation of scientist of varying grades of integrity fueled by the vested interest of medical industry . It has been a almost a daily affair , some of the devices and drugs are recalled or found to be unsafe on patients.

Now the big cat has come out .The Drug eluting stent has fallen from Hero to Zero in a short span of 5 years. It was projected to have zero percent restenosis in 2002 . And now we realize it is Zero percent truth.

What has started as anecdotal reports of late stent thrombosis has indeed become an epidemic in all DES patients. The five studies that has been published in the NEJM this month (March 2007) has convincingly proved how unsafe these stents are in most of the coronary population .

Millions of patients in whom this stent was implanted will carry an impending stent thrombosis and possibly an SCD . Who is to take care of them ?

The DES story is a clear cut case of getting premature approval for a dangerous form of treatment inside human coronary arteries.

It is amazing how the scientist’s eyes are shut by the illusion of knowledge and lure of wealth. How foolish they were to think drug which was administered via the stent will selectively prevent vascularisation and leave the normal endothelium intact . Now they realized , one should not suppress the endothelial growth around the stent and got the fundamental point wrong. Which was the key reason for the astonishing episodes of late stent thrombosis. When we play with biology of nature we have to be little more careful .God has created man and his heart for over a million years . One can not alter it by a 6 month follow up study of DES .

When ICDs were exposed last year , of similar disastrous outcome they were recalled and explanted . How are we going to unstent the millions of coronary arteries ?

Somewhere along the line the medical professionals have lost the battle against the Wall street and NASDAQ . Or how else we can explain repetition of similar events.

The wages for the modern technology , the patients have to pay a heavy price.

Let us all hope common man with common sense will reign supreme over the sixth sense of the uncommon man . . .

“Ignorance is better than illusion of knowledge”

Dr Venkatesan Sangareddi MD , Assistant Professor of cardiology , Madras medical college Chennai, India

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What is the simplest possible guideline for doing coronary angiogram following acute myocardial infarction ?

Posted in Cardiology -Interventional -PCI, cardiology- coronary care, Infrequently asked questions in cardiology (iFAQs), tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , on October 11, 2008| Leave a Comment »

Answer: Do  coronary angiogram  for all patients  who had suffered from an acute myocardial infarction* ( Forget about all those mulitpage ACC/AHA  guidelines !).

For an  interventional cardiologist ,  it is often  considered a crime to  follow a conservative  approach !

*Caution : This one line guideline is not based on scientific fact  but reality based . Ideally one should identify  high risk subsets among the patients who had an AMI .Patients who had complications during the MI get immediate CAG. Others need  a focused LV function asessment ,  pre discharge  sub maximal excercise stress test or perfusion studies .But this concept has been  virtually replaced by pre discharge coronary angiogram for all ,  in many  of the centres in the world.

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