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Archive for the ‘Cardiology-Statistics’ Category

When”Cath lab viability” competes with myocardial viablity … Just carry on !

Posted in bio ethics, cardiology wisdom, cardiology-ethics, Cardiology-Statistics, cath lab tips and tricks, Medical education, Medical ethics, medical quotes, medical satistics, Two line sermons in cardiology, wisdom in cardiology, tagged , , on June 8, 2023| Leave a Comment »

Pure science

Whenever possible ,before doing a coronary revascularisation procedure , check twice the segments you try to perfuse is really short of blood supply and truly needs the procedure. Don’t ever waste your resources and try to blood-feed the dead myocardium. It’ can never be awakened !

Pragmatic science

I was conversing with my colleague recently , who has grown into  suave , Interventional cardiologist with a huge academic & societal repute .He owns a personal cathlab and planning to get one more.

I learnt a non-academic reality lesson from him .

myocardail viablity viability study pci ptca cath lab ethics

When planning myocardial revasascularisation,  apart from myocardial viablity status, there is one more viability issue  which is done in the account books of finance mangers across big hospitals. Its Cath lab viablity.  Trust me, he used exactly the same word ! He went on to explain in detail , how, every day there must be a minimum number of procedures to keep the machine alive. Which is under the eagle eyes of the guys who funded the state of the art lab !

“So, what do you say,I asked him ?”

He was frank enough to admit,  he felt always happy when he is able to convert angiograms into angioplasties.He went on to add , the Ideal CAG-PCI conversion ration should be atleast 3:1 or more.

“Whenver I hear such genuine statments from real world people , it pains,  as it tends to confirm my assumptions ”

Final message

I am wondering with all my lost wisdom. Why should any cardiologist after 30 years of training,  fight for cath lab viablity , and get into a conflict with the very organ they are supposed to care and protect.

When did we become so Inferior beings & fight for the survival of these life less machines ?

Meanwhile, major text books , has un-intentionally facilitated this academic deciet .They have largely taken away the sting out of the snake . Myocardial  viablity , hibernating, stunned  myocardium , are rarely given importance nowadays and made it appear taboo concepts,in cardiology academia.

Postamble.

Will be extremely happy if what is portrayed in this post is not really true.

Reference

Nandan S. Anavekar, Panithaya Chareonthaitawee, Jagat Narula, Bernard J. Gersh, Revascularization in Patients With Severe Left Ventricular Dysfunction: Is the Assessment of Viability Still Viable?,
Journal of the American College of Cardiology, Volume 67, Issue 24, 2016,Pages 2874-2887,

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Tough calls in cardiology :Dengue fever in a patient with prosthetic valve and warfarin !

Posted in Cardiology -guidelines, Cardiology -Mechnisms of disease, Cardiology -Therapeutic dilemma, cardiology -Therapeutics, Cardiology -unresolved questions, Cardiology-Statistics, tagged , , , , on December 5, 2013| Leave a Comment »

Oral anticoagulant usage has been steadily increasing for variety of  indications.Dengue fever is also  appearing in different avatars with  low platelet counts  and bleeding being a primary risk.

I was recently contacted by a physician , regarding a therapeutic dilemma .A young lady with mitral prosthetic valve and a febrile illness diagnosed as dengue . She has a platelet  count of 100,000 .She is on regular warfarin and aspirin .The physician  wanted to know , should he stop the OAC and aspirin ?

What are the options ?

  • Confirm if it is really dengue.
  • Look for clinical bleeding.INR, platelet function tests are not helpful.
  • Continue OAC.You can do that in most situations.
  • Stop OAC only if there is clinical bleeding  episode.
  • Anti-platelet drug usage  is more tricky .One may stop it if the trend of falling platelet is steep by at least two serial measurement.(or 50% fall from baseline)
  • Fresh blood and platelet infusions should be ready .
  • Finally and most importantly , Inform the patient and family about the difficult decision we are making.

*Is  OAC  safer than aspirin and clopidogrel in dengue ?

It is believed OAC has no major  Impact on platelet function .It may not  pose a threat of excess bleeding in the setting of  falling platelet levels .(*Evidence base -nil )

Another potential situation : DES and dengue

The number of DES in developing countries are increasing  where Dengue is endemic . It is not a surprising  to expect  both to  occur together.

Anti-platelet agents  can be problematic .It is better to withhold it during the active phase of dengue.(If the  stent has recently  been deployed you have no option !)

Final message

1.  Prosthetic valve , Warfarin Dengue .

2. DES, Dual antiplatelet agents ,Dengue.

They  extraordinary events  throw a complex therapeutic task .There are only two options .Continue or discontinue ! Whichever way you do , you explain to your clients (patients!)  the (un)reality games we play.

My personal option would be , with hold all hematological drugs during the active phase of dengue .

It is better to believe in the  natural thrombus fighting force . Leave the job of anti-platelet action  to the dengue virus for a week or two and give oral anticoagulants and dual anti-platelet agents a holiday

It may be foolish to rely on the dengue virus to guard against  prosthetic  valve  and DES thrombus , In reality we have to do that !

Reference

No reference exists.It is a statistical mind game.Individual assessment  should prevail. Either way, if something adverse happens court of law should protect us !

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When cost of dying . . . exceeds cost of living . . . this world will go nuts !

Posted in Cardiology classics, cardiology-ethics, Cardiology-Statistics, general medicine, Quotes, Social medicine, Venkat quotes, Wintage cardiology, tagged , , , , , , , , , , , , , , , , , , , , , , , on October 29, 2013| Leave a Comment »

News : In any developed nation , 90 % of  total  health expenditure is  exhausted in prolonging  final few days of  human  life !

When cost of dying   . . .  exceeds cost of living   . . . this world will go nuts !

The current real world  experience  from India’s  five star  hospitals  indicate,  many elderly rich men and women  spend their  last few days  before being buried or burnt  .They spent an average of 15 lakh Rs per death . This amounts to the entire  “life time” cost of living   of  majority of Indians .

modern medicine art living and dying

Image courtesy from Flicker/ Rachel sian photostream

When   human organ donation is considered  a greatest philanthropic act, there is one more excellent alternative for those who can’t do it .If only every super rich translate  their cost of dying  into  cost of  others living !   many new lives  will bloom .

The exorbitant rise in  cost of  dying  in India ,  is a recent development and reflects the affluence , honor , pride and of course lots of prejudice lack of wisdom ! Instead of filling the  deep  pockets of greedy  corporates why not the rich add new  lives   ?  !

Final message

Let all elders  with irreversible conditions , who have finished their life , shall  die peacefully at home .Why don’t we ( Affluent  .  . . would  be cadavers !)  cross sponsor their dying cost to a  public  health , nutrition or medical fund .

After thought

Oh America ,  . . .  Am I right  ,?  Obama thought it and implementing it too !  I would believe , his health care policy is  a  small first step in this  direction  !

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Wide QRS tachycardia : Nurse’s guess work . . . often prevail over Brugada !

Posted in Cardiology - Electrophysiology -Pacemaker, cardiology -ECG, Cardiology -unresolved questions, Cardiology-Land mark studies, Cardiology-Statistics, tagged , , on August 31, 2013| Leave a Comment »

Scientific studies can be fun .In our spare time we often Indulge in rapid  fire sessions. We tested 30  wide qrs ECGs from our archives  (All proven VTs)  and  asked  our  cardiology fellows to apply Brugada criteria . They could   correctly  diagnose  VT  in 18* patients.The same ECGs were shown to the staff nurses of coronary care unit . 24  VTs were correctly identified  it.They did it by  their clinical sense and Instinct. (*12 vs 6  VTs missed)

wide qrs tachycardia svt with aberrancy and vt brugada verecki griffith002

And now , four  clinical data was  provided. (Age , sex , Blood pressure , and  past H/o  MI were given )   The Nurses were able to predict it  28/30  VTs correctly.(97 % accuracy ) and the cardiologists  were able to equal the score now. So obviously clinical sense  was far superior .

Cardiology fellows were more likely to  mistake VT as SVT. This is far more common than SVT mistaken as VT. It is a strange academic  irony ,even the junior most nurses never missed a VT !

Summary

Simple sequence of history and clinical presentation is still far more powerful than ECG data in predicting wide qrs  arrhythmias . Nurses guess work is far superior than cardiologists  in predicting a wide QRS tachycardia as VT.

In fact , the  cardiology fellows are  preconditioned to   get confused   whenever they get a wide qrs tachycardia . Why  not aberrancy ?  In my  experience I have seen this question keeps  erupting inappropriately .Even  shrewd fellows suffer  from an  oscillatory  mind between VT and SVT .This is primarily because , every wide qrs ECG  is likely to  have at least two  criteria that fulfill both VT and SVT.

The implications are  genuine  and far reaching . While nurses  show a patient centric thinking  cardiology fellows  thought process revolves around ECG . Many modern-day cardiac physicians  are disconnected from clinical reality  and are obsessed with  complex EP concepts  and end up with a miserable face in the bed side !

This is not a new  revelation in 2013 . Masood Akthar told this  three decades ago.

Caution
Never try to glorify  guess-work . EP is a great science .The  pioneering concepts have made us understand how a VT emanates, travels , and exit from myocardium . We are able to localise it and ablate it .All credit goes to science . But , when it comes to bedside recognition of VT ,  clinical  sense  is a clear winner .With a  consistently > 90 % predictive value   it  can no longer be called as  a  guesswork   and becomes a hard scientific fact. Especially so , when the  intellectual  analysis of surface ECG   could predict  it  with paltry 70 %  accuracy (Read Reference 1)
Reference
This  analysis startlingly reveal  a fact .The over all accuracy  rate of predicting the wide qrs criteria  by  popular algorithms  is   between 66-77% ,  just 16 numerals   more than  gross   guess work  of 50 : 50 ( This  . . . or  . . . that )
Link to  Masood Akthar article

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A statistical joke called “Non-Inferiority” drug trial !

Posted in Cardiology-Statistics, Uncategorized, tagged , , , on August 27, 2013| 1 Comment »

Of late many drugs are entering the  market  for human  consumption backed up by  Non -Inferiority trials (NIT ) .Few examples.

“The ONTARGET trial: Telmisartan is non-inferior to Ramipril in  New Study Results Published in the New England …”

“Feb 20, 2013 – … in the New England Journal of Medicine Show Dabigatran Etexilate ... daily was non-inferior to warfarin (p=0.01) in preventing recurrent VTE, …”

What is the logic behind these  Non inferiority trials ?

Why it came into vogue ? 

Do you agree with the concept of NIT ?

I have taken the  privilege  of putting my answer in the title. Believers  of NIT please excuse me.

Reference

Non inferiority drug trial

Non inferiority drug trial 2

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