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 When half a dozen guidelines from extremely evidence based “Esteemed cardiac societies”  decide to confront an Incomprehensive cardiologist , there is no other way , but to create  a personalised i-Guidelines on STEMI !

*(i-Idiotic)

 

Yes, Medicine is a funny science ( some don’t agree , Isn’t Art ?) Many of the noble professionals  are silently pursuing their job of saving lives and removing human suffering .Meanwhile, people like this author are needlessly bothered about some Imaginary Issues and write stuff like this one , . . that you are reading now !

Yes, there is an invisible  tectonic shift taking place in the name of  science.The way we practice  medicine currently, it fits in with any of the following descriptions . Divine, Godly,dramatic,miraculous , comical ,cruel or  even outright  brutal ! (I dare not quantify the weightage of each adjectives used above !)

The field of cardiology as I know personally for the past three decades is challenged by  uncontrolled growth (How about proposing 1000 dollar PCSK blocker Evolocumab for a meaningless reduction of few mg of LDL over and above Statin ) Further,the technology goes on to Implode at every corners of wall street ,(Mitra clip for mild MR of DCM ! TAVR for aged Aortic valve )  hijacking  commonsense and cost (where is the effectiveness ?) of every stake holder .

In the process ,the critical  healing power that resides within every biological system is ignored and ridiculed upon .(You become a fool if you say endothelial tissue plasminogen activator and lytic system will take care of a  bulk of the intravascular vascular thrombus if we wait, and  we shall permanently defer an Intervention! Current space aged physicians want to invade every existing (or non existing ) problem with multi pronged military strategy and guess what will happen to the humble  body which becomes the  battle ground.

Coming to the content proper

Sometimes I feel God throws some random truths at an unexpected  time through some extraordinary men ! Here is a most unusual study of its kind from the  Sanctum sanctorum of Medical science , namely  Harvard medical school and Massachusetts  General hospital .I think it was  presented  in ACC Scientific sessions 2018 , Orlando and published in Journal of American heart Association.

Cheers and congratulations to the lead author Dr.Anupam  B Jena* , Physician and professor , Department of health care policy , and Health economist

* A video profile of author is in the reference

There is no surprise a paper with such a title had a huge  media backlash. USA today reacts  . . .

My observations and final message 

The paper from MGH,  Boston  dwells a sensitive area ,of course it has come with a gross conclusion (However,  I feel it has hit the bull’s eye.) Still, for the critics, I want to tell one thing , who can deny the fact ?  the massive evidence base with 100s and thousands of research papers created by cardiology scientific Industry over the decades is largely a damn squib.

(The problem with acquiring this sort of  ready to synthesise knowledge stuff  is, It sits right inside our brain and bonds irreversibly , refuse to leave even if these dubious practices are proven dangerous ultimately !)

It might appear , the only option  to tackle fake science would be through some dramatic ,less than ideal or mediocre research papers (Or even another fake!) As long as final outcome is good for the public don’t bother about methodology  of such studies.(Does it sound in any way I am a supporter of Donald Trump ,! No I am not !)

Reference 

Now have a look at this (a long post ) which I wrote some time  back. Find out whether  these  scribblings of mine seem to have grown some scientific backing now .

A brief Info about  the author of this unusual paper that has put the field of Interventional cardiology into tail spin and fluttering in cross winds !

One car company  recalls 100s of  thousands of cars for faulty equipment  issues in recent years . It goes on to add , beware , it’s potentially dangerous  . . . please fix it and bring your car at the earliest !

Toyota-Gra

Mean while , scientific medical literature is flooded with dangerous articles, papers and guidelines . . . and  pose serious threat to your patients !

Please search for the junk knowledge and then go on to expose, erase and  ,  . . . and throw it to dustbin ! After all , research is searching for truth , again and again !

Let us welcome a new era , where we shall get alerts about wrong knowledge  withdrawals and reversal ! Let it challenge  the self proclaimed sancto-scientific medical world  and a new medical literature cleansing movement (MLCM) begin in every sub specialty.

One such paper from Yale is linked below .

medical reversal

Finally  . . . the forbidden message !

venkat quotes 2

Conquering  left main disease is considered as crowning glory for the Interventional cardiologists. For over three decades , CABG has remained the undisputed modality which is being challenged  today. Fortunately, the Incidence of true isolated  left main disease is  low .(If Medina bifurcation subset is excluded)

 

left main

With growing expertise , advanced hardware and Imaging ( like a 360 degree OCT fly through view ) one can virtually sit inside the left main and complete a PCI .

Still , coronary care is much . . . much  . . . more than a technology in transit !

Most importantly, these complex PCIs require rigorous maintenance protocol  with meticulous platelet knockout drugs , patient compliance and the genetic fate of drug efficacy . (Clopidogrel has since entered the final laps of inefficiency while Ticagrelor has some more time I guess !)

What is the current thinking  about  unprotected left main PCI ? Let us know it from real life experts !

For those answered , yes to  the above question please leave this page , as the following question might  trouble you much !

While competent surgeons are waiting to tackle left main by surgical means ,there are many centers which are Inclined towards  PCI though we lack long-term outcome (At least 10 years like CABG )

Why do you think this is happening ? Are you ready for another crooked poll ?!  

What exactly is left main disease ?

Some of  us also suffer from a knowledge gap and tend to think  Bifurcation lesions  and left main disease are two distinct entities .The fact of the matter is , significant subset of bifurcation lesions are Indeed either left main equivalents or true left mains ( Medina 1,1,1 would constitute > 50 % all  bifurc lesions )  If you include Invisible left main lesions in Medina ( 0,1,1 or 0,0,1 ) detected by IVUS/OCT  it might reach easily cross 90% (Scientific guess !)  Does that mean we have to think CABG even for all complex bifurcation lesions ? and reserve left main disease for isolated discrete mid shaft or ostial left main ?

Final message 

My observation (Sincere to my limited conscience !) at least in this part of the world is : Left main Interventions are  “perceived as pride” and its more related to “show of expertise” and is little to do with patient outcome.Unfortunately , cardiologists should not be blamed for it in isolation as the studies they follow are conflicted.

Forget SYNTAX/PRECOMBAT trials, the two famous studies EXCEL (Favor PCI) and NOBLE were published in 2016 made our life tough .One suggested PCI is acceptable /on par with CABG, while the  other one put CABG superior , ensuring clarity  replaced with confusion ! When we have a dispute , logic would suggest we should fall back on the status quo ie “CABG is superior” unless proved convincingly. Many sections of cardiology society failed to appreciate this.

Post PCI thoughts

*It may not be that hard to do a complex PCI . But, it’s never easier to understand current cardiology literature that is supposed to raise our intellect , which has a direct relevance to patient welfare. Note, many crucial , high stake studies  tend to play academic deceit games  with  linguistic and statistical hyperboles like Non Inferior , likely superiority , Never inferior , near equipoise , regression of hazards, virtual follow-up in  real vs trial world etc , etc !

I can only hope for a better scientific world !

Reference 

  1. Which is the best option for left main disease PCI or CABG ?  Journal of Individual wisdom and evidence based conscience : Volume 1 Chapter 1- Coronary Intellect : Pages 0 to ∞ Jan 2018.

Answer 

Though PTMC in the presence of LA clot is an option in low risk clots , my strategy would be the last one ,whenever feasible. Intensive, monitored Heparin /Oral anticoagulants ( Heparin 5000 units tds or qid  or Low molecular weight heparin Enoxaparin  40-60mg twice a day , Tablet Warfarin /Acitrom with an INR of 3 ) will dissolve  LA clot in  30-50% of times.(Our experience).

The percutaneous clot retrieval system is not available as on 2018.Aortic filters are FDA approved during TAVR. (Why not use the same in PTMC ?)  LA Catheter based regional lysis through PFO is can be an option if patient agrees to the risk.

How long to wait for clot dissolution with Heparin /OAC?

Most small clots or intermediate sized clots ((Up to 2 CM ?)  have been dissolved by 3  months. Even large clots gets dissolved at least in few Instances.Please note, this strategy is applicable only with valves that is fit for PTMC. All others are referred for surgery.

How does heparin lyse a clot  ?

Its a miracle to see it happen, though heparin / OAC are  never considered as thrombolytic agents .It happens because  both heparin and OAC tilts the local   endogenous fibrinolytic forces and thrombus melts , dissolves or disappear altogether. (I am waiting for the day , the scientific community to re-label heparin as a thrombolytic agent, Indirectly though !)

Is there a risk of dislodgement of LA clot during heparin /OAC therapy ?

This question shall be addressed to  God ! It all happens if bad luck strikes you and your patient.

Be wise  . . .  and call your surgeon Immediately when you encounter something like this !

Even if the valve is perfectly eligible for PTMC , high risk  mobile clots, history of  embolic episodes , probing and hyper-googling patients , its better to refer for surgery Immediately. Wait and watch game has a definite risk of stroke and it is especially bound to happen if your patient or their family is anxious !

Reference

Ventricular pressure volume loop is an Important ( often feared !) concept to learn for cardiology fellows . . . I would say , It is not that hard to understand !

These loops tell us the secret  hemodynamic story of a 300 gram “mass of muscle” called the heart  and how It handles about 100 ml of blood every beat and successfully ejects around 70 ml into Aorta and Pulmonary artery *

108356heart_beating

While doing this life sustaining job , It would seem the heart muscle  conducts a perfect, non stop, hemodynamic orchestra with 4 electro-mechanically coupled phases which is depicted as classical ventricular pressure volume  loop. Mind you, this loop is plotted pressure volume data from a single heart beat and it can’t be time correlated with heart sounds or ECG as the two parameters loop around in same time cycle.

Watch this animation , carefully and read the appearing annotation that come along with each phase.That should suffice to understand the basic. (For Audio version go the video link in the reference )

Modified from a clipping from Giphy.com.Original source of this Image is not located. Whoever has done this thanks and it’s a great attempt.(I have tried a fusion Image of doppler mitral Inflow in diastole and Aortic pressure curve during ssytole to bring PV loop an anatomical perspective.)

*Note: When we say PV loop it means about by LV by default . We do have seperate RV ,LA (even RA?) PV loops.

Is there clinical application for  PV loops ?

It may not have any direct use , but understanding  how a ventricle works in normal conditions or at distress especially during acute decompensations or after surgery  is vital. With modern gadgets like LV assist devices,  Impella used widely and to assess hemodynamic efficiency of transplanted (Very soon total artificial hearts) , PV loop analysis of both RV/LV will be critical.

Is there any simple Lab modality that can draw this Loop curve instantaneously ?

echocardiography lab methods for ventricular pressure volume loop

 

Very few companies make it . AdInstruments that make power lab monitors, enable us to visualise PV loops invasively .

 

Can we get PV loops non invasively by Echocardiography ?

Echocardiography  provide us both volume  and pressure data.With improving accuracy of data it should be possible to plot the loop manually with some effort. (Still , we can’t get pressure in all points of cardiac cycle )

I guess, sooner 3D volumetric machines with automated online doppler pressure data across the valves  can help us draw the ultimate LV functional  curve live on real time.If that happens cardiologists will be further enriched and hemodynamically enlightened !

Final message

The shape , size , timing and the slopes of this loop  givs us vital info about the functional aspects of ventricle. First one should understand the normal loop , then , we can dwell on the effects of acute and chronic lesions like regurgitations, cardiomyopathy ,cardiogenic shock etc.

Reference 

An excellent knwoledge base on the topic with a  video 

Dr. Richard E. Klabunde, PhD

In the modern era of cardiology,  PCI has become the single therapeutic modality  that determines the survival of both cardiologists and possibly their patients! The procedure is all about launching  a metal coil inside the coronary artery of a live beating heart.

Post dilatation vs pre dilatation

Millions of diseased and (not much) diseased coronary arteries are serviced (either re/deconstructed ) world-wide on a day-to-day basis.The benefits of the modality is  directly related to the wisdom of treating cardiologist and patient’s luck than the original severity of the disease. However, with greatly improved coronary  metallurgy , well assisted by drug coating technology and antiplatelet Industry , cardiac physicians believe they have reached the zenith of this procedure.

But the truth is , PCI still has many lingering issues regarding safety , efficacy and cost effectiveness.Early hazard in the form of acute stent thrombosis and sudden death is  a  reality. Blaming it on patients and their lesions ( condition of blood , gene included) , metal behavior is easy , but, wrong selection (Ignoring the option of CABG) and technical inadequacy of the procedure in the setting of complex  vessel wall disease (Hard calcium , deep tunnels , fissures , dead spaces ) is a major cause for concern.

Some personal thoughts about Post dilatation 

Lesion preparation , pre/per-dilatation /POTS , etc by itself  a big topic (which is not discussed here) Post dilatation after direct stenting is much more vital concept that determines not only the immediate but also the , Intermediate and long-term outcome.

Is routine post dilatation harmful ? or beneficial ?

This is the most tough question to answer . The answer is both Yes and No !  While it was thought useful and mandatory by some , the oppositeis also being adviced few  (CCL 2003 POSTIT trial)

What balloon pressure one should post dilate ? At what compliance ?  What is the Inflation time ? 

It’s akin to asking a musician  how to play a piano with fingers or guitar with various strings !

The effect of balloon pressures in the long term outcome. note both low and high pressure dilatation ( blue and orange worms ) hike the risk of restenosis. Too gentle is as dangerous as too harsh making post dilatation a secret and unique art.

 

Physics of post-dilatation  . . . again more questions !

  • Is there a role for compliant balloons ?
  • Does the compliance of balloon gets altered with hard lesions?
  • Is regional compliance matters ?
  • Can balloon exert same radial pressure all 360 degrees ?

It’s very likely, the moment balloon encounters an area of resistance it tends to avoid that area and would love to drag on to the area of least resistance and this is often diagonally opposite  zone of hard lesions ( if that segment  is free from hardness).Then , it  will face more stress and likely to bear the brunt of the force risking endothelial disruption . In other words , concentric hard lesions are more amenable for dilatation than patchy hard segments. While the physical forces vary in a stented vs non stented segment , the principle of dynamic forces on static tissue masses  with Intervening metal is too complex. (Mind you , we are not discussing  entirely different  issue , ie  thrombus laded ACS lesion , where displacement and pinching of of inter-strut thrombus into distal circualtion would cause no reflow!)

Impact of newer hardware

*Ablation catheters either rotational or Orbital can help , but must be done prior to stenting .Unfortunately , the hardness of a lesion is often realised  only after stenting

Is selective high pressure inflations over a particular struts possible ?

As of now , it would be challenging ,( if not outright impossible) .

Let us realise with all our intellect, complex PCI as a whole is taking an uncalculated risk  and leave the rest to GOD and DAPT !

Reference article 

In an elegant study of more than 90000 PCIs from Sweden and  Holland (Ref : Fröbert O, PLoS ONE. 2013 ) found routine post-dilatation pushes the harm curve little more than benefit.  The was more with both low and very high pressures .

The outcome of post-dilatation  in 900,00 PCIs 

 

Estimated cumulative event rates of stent thrombosis (Panel A) Restenosis (Panel B ) Cumulative death (Panel C) in relation to post-dilatation .Note the height of coronary Irony, Post dilatation Increase stent thrombosis and restenosis but saves life too !

 

The stunning truth revealed in this study was , early deaths were more common if  post dilatation was not done ! (Panel C in above figure) 

Role of Imaging in the decision-making prior to  Post dilatation

IVUS, OCT has been extensively used in recent times to diagnose suboptimal deployment and to asses lesion morphology.Though they are expected to improve the quality of angioplasty and hence the  outcome , the real world scenario is not really confirming our expectations.

This is because , eagle-eyed HD  imaging throws  more questions than answers in many and it converts coronary artery into a confused Pandora’s box . In fact these Imaging modalities has created fresh confusions , definitions and guidelines for malapposition under and over expansion , strut fracture, plaque prolapse, internal elastic laminar stress.( Still , I am not able eo understand  whats malapposition  vs  under deployed stent from a practical , pateint point of view !)

Is the Self expanding  stent is the answer ?

The conundrum of post dilatation might be cracked if the built-in radial force of self expanding stents is optimally utilised .This could be useful in some  tricky lesions when the vessel goes for progressive Glagovian  remodeling post PCI. The self expanding stent because of the stored potential energy keep hugging the vessel wall as it expands centrifugally.

Final Message

Post dilatation is neither a mandatory nor a sacred  protocol in cath lab. However , it would seem bulk of PCI’s still will require it . Its done judiciously with reference to   clinical setting, (ACS vs CCS) , type and location of lesion , stent characteristics etc .Most Importantly , the experience of the cardiologists counts ,and he or she will decide when, where, how much of post dilatation is required (or not required) .

Please remember , PCI as a whole (more so the Pre/ Post dilatation !)  is an art by itself. It’s never learnt in text books or even  watching  live work shops. Every young Cardiologists are enouraged to master the art of PCI ,  with a huge caveat . Always ensure  patient’s  Interest are placed first in every step forward. If you are not clear in comphrehending  “What is meant by true  patient’s Interest ? never Indulge in the procedure or call your mentor , if you have one !

Reference

1.Brodie BR1, Cooper C, Jones MCatheter Cardiovasc Interv. 2003 Jun;59(2):184-92. Is adjunctive balloon postdilatation necessary after coronary stent deployment? Final results from the POSTIT trial. Postdilatation Clinical Compartative Study (POSTIT) Investigators.

2.Fröbert O, Sarno G, James SK, Saleh N, Lagerqvist B. Effect of Stent Inflation Pressure and Post-Dilatation on the Outcome of Coronary Artery Intervention. A Report of More than 90 000 Stent Implantations. Agostoni P, ed. PLoS ONE. 2013;8(2):e56348. doi:10.1371/journal.pone.005634

3.Zhang Z-J, Marroquin OC, Stone RA, et al. Differential effects of post-dilation after stent deployment in patients presenting with and without acute myocardial infarction. American heart journal. 2010;160(5):979-986.e1. doi:10.1016/j.ahj.2010.07.007.