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Mohandas Karam Chand Gandhi ,  father of my country , India , made these observations in year 1925  about the  fundamental constituents of  violence in society . These words of monumental wisdom came when he was  addressing young Indians in a country- side rally .

mahatma gandhi quotes medical science humanity

Note, his finger points to , what  exactly is relevant to our profession ! He emphasized this  nearly  100 years ago, when medical science was at its infancy .One can only guess what would be Mahatma’s comment about our profession in it’s  current form !

Should we include moral, behavioral and ethical classes  right from the first year of medical  school along with Anatomy , physiology and bio chemistry.Medical council of India obviously need to burn more mid night oil , I wish it happens in my life time. !

Following are revered  facts  . . .  among the  “Guardians of   Cardiology” !

myths-truths-300x300

When false truths are synthesized to conceal a true myth . . . where will the poor myth complain ?Following are revered  facts  . . .  among the  “Guardians of   Cardiology” !

  • Primary PCI  is a greatest innovation  in modern day cardiology .Without this modality  most  STEMI patients will buy Instant  tickets to grave yard !
  • A cardiologist who intends to  thrombolyse  a STEMI is considered as a low quality cardiologist .
  • Streptokinase should have  no place in the crash carts of modern coronary care units.
  • There is nothing called “Time window” for rescue angioplasty.
  • VVI pacemaker  will convert an electrical problem of heart block into a mechanical one by depressing LV function .
  • Digoxin is an obsolete  drug even in well established cardiac failure with dilated heart.
  • Beta blockers not only fail to control  blood pressure smoothly , it often converts  a hypertensive individual into a unhealthy one  by it’s prohibitive side effects !

 

Here is a  video recipe  !

Please click here to  see more videos from my you tube site

” This is post is 5 years old , Newer developments should be given considerations”

 

STEMI is the “Numero Uno” of  cardiovascular emergency .The  treatment has evolved over decades,  right from   the primitive  arm chair approach to the  air dropping of  patients  over the cath  lab  roofs  for primary PCI ! We realise by now ,both are extreme forms of treatment and  may  have unique  hazards. What we forget is the , the natural history of STEMI is too  much dependent on the degree of initial damage to the myocardium , and it is very difficult to alter this,  however good is the therapeutic strategy .  We are yet to find an answer regarding the mechanism of primary VF and modes of preventing it. We also have no answer for  ,  why  some  develop myocardial damage  very fast and  the  cardiogenic shock occur in an  accelerated fashion. (Fate ?)

Many would consider  ” non availability of   infrastructure and expertise ”  is the major issue  for  primary PCI . But the real problem is much more than that .When an  illusion of knowledge is  created by constant bombardment of data  , it is natural for human beings to believe whatever is told or printed in books and journals. We cardiologists are made to believe thrombolysis is a far . . .  far  inferior treatment than primary PCI in STEMI .  It is not so in any stretch of imagination !

The fact that,there is no entity called ” Failed primary PCI ” in cardiology literature  , would  suggest how biased we are against thrombolysis. Every cardiology  resident will  recognise  thrombolysis fails  at least 40% of time .Yes , it is  a  fact  , but the irony is , this   is  often  used   to convey a surrogate  meaning , that  is , primary PCI is  near 100% successful !

How  do you assess success of primary PCI ?

Unlike elective PCI where the criteria is too liberal, we can not afford to adopt the same in an emergency PCI. Here the aim of the procedure is entirely different (Salvaging dying myocardium vs pain relief  ).

It’s still a  mystery ,  while  thrombolysis is vigorously assessed  for it’s  effectiveness   primary  PCI is rarely  subjected to the same scrutiny  . A check angiogram  after the procedure ,  is all that is done . . . and every one  leaves the cath lab happily. The  effect of primary PCI on ST segment ECG resolution must be documented immediately after PCI. While ,  It is mandatory to take ECG after 60 -90 mts after thrombolysis , this sort of protocol is rarely  followed after PCI.

If the ST segment  fails to retract  > 50% immediately  following PCI  the procedure  should be  deemed to have failed . Further , unlike thrombolysis  in primary PCI , the ST segment has to regress within 10  mts , as IRA patency occur instantly .If we apply this criteria , the success rate of primary PCI would be far less than what we believe*

* Not withstanding the official lesion , hardware, related failure. If we encounter a severe triple vessel disease , with a bifurcation lesion and thrombus it’s  a tough exercise as we are racing against time .

Primary PCI  Camouflaging  in semantics

  • A successful but  delayed   primary PCI  is actually a failed PCI
  • A  complicated  primary PCI  often  reach the equivalence  of   failed PCI
  • No  reflow is almost synonymous with failed primary PCI as successful correction of no reflow occur in minority.
  • Not all TIMI 3 flow is converted into myocardial flow.
  • Renal dysfunction following excess dye has a  high  morbidity
  • If patient  develops significant  LV dysfunction following primary PCI it is a failed PCI.
  • Finally if the cost of primary PCI exceeds the insurance limit it is  economically a  failed primary PCI as the patient  has to spend double or triple  the amount of sum insured .This stress has resulted in many recurrent coronary events .

Why is it important to recognise failed primary PCI ?

For failed thrombolysis we have a strategy . Unfortunately , even in this modern era  we have  no useful  strategy for failed primary PCI . Handing over a patient to a surgeon in a such a situation is considered by many as a great rescue strategy but in real world it does no good in most of the patient.

Doing an emergency CABG in a sinking patient with a battered coronary artery is no easy job /Many times it only rescues the cardiologists from the embarrassing situation of facing the relatives who ask for explanation.

So , what can be done at best , in failed primary PCI ?

  • CABG can be an option but still questionable !
  • Most times  there is  no other option except to fall back on the medical management.
  • Intensive anticoagulation and one need to consider even a rescue thrombolytic treatment !
  • Some times we can only prey !  Failed primary PCI for a patient in cardiogenic shock with IABP support is near death sentence !

Final message

  • Remember ,  success of primary PCI   is  not in  wheeling out a  patient  alive out of cath lab   , with a TIMI 3 flow  in the IRA ,  but in  garnering significant   myocardial salvage   which  should have an impact on   intermediate and long term  outcome .
  • Do not ever think primary PCI is a sacred treatment modality in STEMI  and the job of the cardiologists ends there. It is vested with  lots of important complications – defined, undefined , recognised,  unrecognised, reported, and unreported ,  concealed ,denied, poorly understood, etc etc.
  • There are  equally  effective, less dangerous treatment modality available .
  • Decision  to do primary PCI  must not be based   only on the  “affordability and  availability”  of  cath lab and expertise !
  • In  clinical cardiology practice,  no  procedure  is  great   & nothing is inferior either  !  Every thing has to be used judiciously , appropriately  and  intelligently (Intelligence is synonymous with common sense many times!)

Coming soon

Surgeon’s real time experience of operating  on a failed primary PCI. To our surprise , only a handful of surgeons  have this experience

It is often said life is a cycle , time machine rolls without rest and reach  the same  point  again and again . This is  applicable for the  knowledge cycle as well .

We  live a life ,  which is infact a  “fraction of a time”(<100years) when we consider the evolution of life in our planet for over 4 million years.

Man has survived and succumbed to various natural and  self inflicted diseases &  disasters. Currently,  in this  brief phase of life  , CAD is the major epidemic , that confronts  modern  man.It determines the ultimate  life expectancy . The fact that ,  CAD is a new age  disease   and  it was  not  this rampant ,   in our ancestors  is well known .The disease has evolved with man’s pursuit for knowledge and wealth.

A simple example of how the management of CAD over 50 years will  help assess the importance of  “Time in medical therapeutics”

  • 1960s: Life style modification and Medical therapy  is  the standard of care in all stable chronic  CAD The fact is medical and lifestyle management remained the only choice in this period as   other options were not available. (Absence of choice was  a blessing as we subsequently realised  ! read further )
  • The medical  world started looking for options to manage CAD.
  • 1970s : CABG was  a major innovation for limiting angina .
  • 1980s: Plain balloon angioplasty a revolution in the management of CAD.
  • 1990s: Stent scaffolding of    the coronaries  was  a great add on .Stent  was too  dangerous  for routine use  was to be used only in bail out situations
  • Mid 1990s : Stents  reduced restenosis. Stents are  the greatest revolution for CAD management.Avoiding stent in a PCI  is unethical , stents  should be liberally used. Every PCI should be followed by stent.
  • Stents have potential complication so a good luminal dilatation with stent like result (SLR)  was  preferred so that we can avoid stent related complications.
  • 2000s: Simple  bare metal stents are not enough .It also has significant restenosis.
  • 2002: BMS are too notorius for restenosis and may be dangerous to use
  • 2004 : Drug eluting stents are god’s gift to mankind.It eliminates restenosis by 100% .
  • 2006:  Drug eluting stents not only eliminates restenosis it eliminates many patients suddenly by subacute stent thrombosis
  • 2007 : The drug is not  the culprit in DES it is the non bio erodable polymer that causes stent thrombosis. Polymer free DES  or   biodegradable stent , for temporary scaffolding  of the coronary artery  (Poly lactic acid )  are likely to  be the standard of care .
  • All stents  are  potentially dangerous for the simple reason any metal within the coronary artery  has a potential for acute occlusion.In chronic CAD it is not at all necessary to open the occluded coronary arteries , unless  CAD is severely symptomatic in spite of best  medical therapy.
  • 2007: Medical management is superior to PCI  in most of the situations in chronic CAD  .(COURAGE study ) .Avoid PCI whenever possible.
  • 2009 :The fundamental principle of CAD management  remain unaltered. Life style modification,  regular  exercise ,  risk factor reduction, optimal doses of anti anginal drug, statins and aspirin  is the time tested recipe for effective management of CAD .

So the CAD  therapeutic  journey  found  it’s  true  destination  ,  where it started in 1960s.

Final message

Every new option of therapy must be tested  against every past option .There are other reverse cycles  in cardiology  that includes the  role of diuretics  in SHT , beta blockers in CHF etc. It is ironical , we are in the era  of rediscovering common sense with sophisticated research methodology .What our ancestors know centuries ago , is perceived to be great scientific breakthroughs . It takes  a  pan continental , triple  blinded  randomised trial   to prove physical activity is good  for the heart .(INTERHEART , MONICA  studies etc) .

Medical profession is bound to experience hard times in the decades to come ,  unless we  look back in time and “constantly scrutinize”  the so called  scientific breakthroughs and  look  for genuine treasures for a great future !

Common sense protects more humans than modern science and  it comes free of cost  too . . .

STEMI occurs due to acute occlusion of a coronary artery  (ATO) which needs emergency opening at the earliest, ideally within  3 hours , or up to 12h . The opening shall be either by pharmacological / catheter means  or both. After 24 hours opening  a ATO has questionable benefit unless the patient is hemodynamically unstable or symptomatic.

What is a CTO ?

Traditionally we believe 3 months is the period to call a coronary occlusion as chronic.(Previously it was 6 months) This time frame was considered appropriate based on our understanding of the infarct process , that may take up to 3 -6months for complete healing of infarct  .This 3 month period is arbitrary as the chronology of intra-coronary lesion organisation  is different from myocardial infarct healing. Its worthwhile to note the chronicity of  a coronary lesion and its morphology is nothing to do with the quantum of myocardial damage it inflicts .This is because in many patients with STEMI who present late , the ATO progresses to CTO silently without any clinical demarcation or progressive myocardial damage.

chronic total occlusion acute total coronary bridging collateral

If 24 h is the cut off point for opening the ATOs to accrue any meaningful benefit , can we call  all ATO’s beyond 24 h as  physiological  CTO equivalents ?It doesn’t make sense  isn’t ? But , consider this , how do you call an occluded coronary artery between 24 h t0 say  2 weeks or 2 weeks to  to 3 months ? Sub acute total occlusion (STO) ? .Some  experts have argued to remove CTO as an entity from acute coronary setting .This can’t be done as chronicity has to set in  for ACS lesion as well. Obviously , we have a nomenclature issue here. We require a  new terminology to differentiate CTO related to ACS and CTO related to chronic coronary syndromes.

Therapeutic implication

The moment we  diagnose  a true chronic total occlusion , not only the urgency of intervention but also the indication to open becomes  questionable in an otherwise asymptomatic population.

An ironical situation often arises , when we can’t technically open a ATO in a one week old STEMI .However , the same lesion one may  open after 3 months as it has acquired a new name by now as CTO , which is perceived  a lesser guilty act of violating the sacred PCI guidelines !

effect of inspiration on jvp and bp pulsus paradoxus bernhiem effect ventricular interdependence

Image  modified  from  http://www.anatomygallery.info

That’s  normal . . . what happens during pathological states ?

There are important diseases  that  restricts entry of blood into right heart chambers. They can occur either in an acute  (Tamponade) or in chronic  fashion like constrictive pericarditis  and restrictive cardiomyopathy.These entities  show distinctive impact on JVP and systemic pulse.

The two pathognomonic signs are Kussmaul sign and pulsus paradoxus* that go hand in hand in most  situations.Inappropriate elevation of JVP with inspiration is termed as Kussmaul sign , while exaggerated fall in systemic BP with inspiration is called Pulsus paradoxus.The later is the  arterial counter part of  Kussmaul sign in JVP .However, there can be dissociation between these two signs occasionally.

* Pulsus paradoxus is a term originally  used by Kussmaul when he noted heart sounds were  retained while pulse dissappeared  in  patients with cardiac  tamponade .Later we realised the loss of pulse was linked to inspiratory cycle  of respiration. To make  this sign objective  sphygmomanometery  criteria was formulated which measured the difference between inspiratory  and expiratory korotkoff’s  sounds .

Coming up next 

Why Kussmaul sign  is often absent in Tamponade while  its arterial counterpart pulsus  paradoxus may still be conspicuous ?

Right ventricle,being a venous chamber has distinct anatomical and physiological features to carry out this function.RV has a complex shape, its triangular in long axis and  crescent like in short axis , thin (<5mm)  more distendable  .Contraction of RV begins slightly early but ends later than LV  (30ms )

https://www.youtube.com/watch?v=GH5trHYjozI

RV receives blood from RA and ejects in to PA in a sequential manner .The inflow, body and outflow contract somewhat like  intestinal peristalsis. This is facilitated  by the incremental  delay in the electrical depolarization of right ventricle.In physiological conditions, the later half of QRS  is  responsible for RV activity and RVOT is the last to contract. (This intrinsic electrical and mechanical  delay in RV contraction is a physiological inter ventricular  desynchrony . One  should be aware of this when planning cardiac resynchronisation therapy in cardiac failure.  )

Click over the image for an animation of RV contraction.

wpid-wp-1430586787404.gif

Image courtesey Oxford spcialist hand book in cardiology :Echocardiography Paul Leeson , Second edition ,.Oxford university press 2012 Multi media .

Note:LV is  a fairly   elliptical and strongly  muscular pump and contracts in a  single go with maximum force.(dp/dt).

Final message

Though both right and  left ventricle originate from same  straight heart tube , developmentally the right ventricle evolves for a different form and function . Now,we realise there are lots of sharing of parental muscle fibers that engulfs and bonds both chambers.(Mind you ,This is the fundamental mechanism of ventricular interdependence.Of course ,IVS is a common wall shared lifelong by both chambers  without any (sibling related?)  hemo-dynamic dispute !

3D echocardiography and MR imaging has helped us to understand the RV morphology better and exciting articles written by pioneers are available  free for those who are interested.

Reference

These two quotes  on practice of medicine are close to my heart , one from Voltaire , a non medical man (a French poet )  and  the other from ,one of the greatest medical professional of our times, William  Osler .

gretest medical quotes william osler voltaire

It is amazing ,how the thinking pattern of a  philosopher  and a true scientific professional living  centuries apart are almost in sync with a great medical reality !

J point is a critical point in the  ECG  when the ventricles hand over the baton in  the  electrical relay race from depolarization to repolarization .This the time the sodium  channels extinguish itself  and the potassium current begins its activity  from Phase 0 to 1 .

If the  potassium channels  activate little early and snatch the baton prematurely from sodium , we get early repolarization pattern .When this happens , the J point of ECG show a conspicuous wave  called J wave , originally  denoting  Junctional wave between QRS/ST segment  (Now  perceived as  Jitter waves ?) The other implication of premature K+ activity is , lifting up of  ST segment , making it the most common cause of non ischemic ST elevation.

* J wave in hypothermia is referred to as Osborne wave and  may not be  not related to ERS(Ref.4)

J wave and J point early repolarisation syndrome

Image source.www.cardiology.org

The Ito current is responsible for the phase  1 of action potential (AP), where a rapid outward k + ion flux take place and draws the dome of AP . The dynamics of Ito is complex .It depends  upon the density of epicardial K + channels , which are  clustered in a heterogeneous manner .There seems to be a concentration gradient   along the epicardium and endocardium , making the wave appear prominent in some. This is especially true in healthy, athletic  male population  where we have some evidence for androgen  to  play a role on how  these channels will behave.Here comes the overlap between Brugada  syndrome and ERS as well.

The subset of patients with J wave pattern were recently shown to have increased risk of primary VF due to phase 2 reentry ,  when they develop ACS. (Rather J wave pattern was more common in patients who had primary VF following STEMI(Ref 1).This resulted in a spate of worrying articles .Now we know , the  fear is  largely unfounded ,the risk is far less.

Current thinking is,  persons who have asymptomatic ERS pattern with prominent J waves should not be investigated electro-physiologically . (Please remember , every human  heart can be induced  to VF in EP lab  if appropriately  stimulated ! )

In fact , I used to tell the  young men  who  harbor  prominent J wave , as a marker of healthy heart  rather. Let us not  fear them with a remote risk  that could be as  negligible as risk of  intercontinental flight crashing into the ocean  !

References

1.Haissaguerre M, Derval N, Sacher F, et al. Sudden cardiac arrest associated with early repolarization. N Engl J Med. 2008;358:2016–2023.

2.Idiopathic Ventricular Fibrillation “Le Syndrome d’Haïssaguerre” and the Fear of J Waves , Sami Viskin, J Am Coll Cardiol. 2009;53(7):620-622. 11

Have you felt like this query any time in your office ?

If “Yes” is your answer, then you are not alone .There was a unique  conference  that  took place  in 2010 to answer the same query in Rome , Italy on behalf of Italian cardiology society  , where this entity is researched more than any other place.Its worth going through this.

Reference

PTMC involves a critical step , where one has to cross  the IAS to reach the LA.The septal puncture remains  somewhat a blind procedure in fluoroscopy .(Echo can still assist us. )

Stitch effect is a rare complication where the needle pierces the intrapericardial space from the right atrial side and re-enter the left atria .This wrong way entry into LA may not be recognised  untill the sheath is withdrawn and a cardiac tamponade ensues after removal.

Where exactly the stitch  occurs ? What are  the anatomical planes ?

This usually  happens in the superior aspects of   IAS , abutting the roof of RA and LA . The alignment of IAS with reference to RA and LA is key a determinant.We know in mitral stenosis LA can outgrow the RA , bringing   superior aspect of LA  in a different  plane with reference to IAS  .The IAS puncture site may overshoot , enter the pericardial  space and  stitches the non IAS aspect of RA and LA together , of course  still guiding us  into LA through a false pericardial track (Which is not recognized )

stitch effect ptmc stich phenemenon

Note : The intra-pericardial track can be more complex than we realise as a significant part of posterior LA is extra-pericardial and transverse sinus of pericardium can get involved as well.

 

Our understanding(mis ?)  suggests at least four different stitches are possible

  1. IAS-Pericardial space -LA roof
  2. RA-Pericardial space -LA roof

Other complex tracts (Based on theoretical assumptions . Please note , in  some of the fatal punctures the exact  route was not identified by surgeons even under direct  vision . )

3.RA-Pericardial  space -Extra cardiac-Reenter LA

4.RA-IAS -Pericardial space-Extracardiac -Reenter LA  ?

What are the possible bleeding sites in stitch effect ?

There can be two sites of active bleeding .One from RA exit point and other from LA entry point of needle.Extra-cardiac oozing can also occur if the needle has pierced the outer pericardium before entering LA.

Management

  • Recognition is the key. It requires extra anatomic acumen to diagnose the false track before we insert and withdraw the sheath.Echocardiography should be liberally  used if you suspect a false track .
  • Tamponade  is to be  drained promptly and emergency surgery is usually required if re-accumulation occurs.
  • Closing the puncture site with devices has been successfully  attempted in few patients .A small ASD device (or a Plug ? ) is expected to close  the site of  puncture . Since the anatomy  can be complex ,one may need to  close with two devices , one on LA side and other one RA side .The radial force that closes the tear and long term retention of these device are not known .

Related topic

Other mechanisms of cardiac  tamponade during  PTMC

 

 

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