Feeds:
Posts
Comments

Posts Tagged ‘ptca’

Bifurcation PCI is a modern-day Cardiologist’s fascinating professional adventure within coronary arteries. Of course, one of their Intentions is to do good for the patient. Bifurcation lesions (BFL) are a special subset of lesions, that looks challenging, more because of the potential biological aftermath following the delicate construction of a grade separator at a critical site. Mind you, it’s done within a live flowing artery and subsequently needs lifelong maintenance.

Strategies for BFL

  1. Strictly committed* single stent strategy (Irrespective of what may come, LCX or LAD  pinching let me take care . Don’t worry strategy *May sound dangerous, but still, it doesn’t make other strategies less ominous) 
  2. Provisional single stent strategy with elective cross-over for truly poor result /cosmetic/peer satisfaction  purpose
  3. Provisional single stent with bail-out cross-over. Often happen as an emergency  (Not all techniques are amenable for this)
  4. Elective planned two stents (Still, flexible  to revert to single stent if the situation allows)
  5. Elective, strictly committed, prefixed  two-stent strategy  (No going back strategy/ Not really a professional PCI )
  6. Always remember, SYNTAX or no SYNTAX CABG is the safe & best bet for many severely symptomatic patients, with complex as well as non-complex BFL lesions esp in diabetic patients.

Wait, there are two more.

7. Please note, there is one benign strategy, that is always available, but hiding deep in the interventional cardiologist’s sub(non)conscious minds. It is a zero radiation, zero contrast, and almost zero cost strategy. Yes, It is “No stent strategy’ also called exclusive medical management, currently referred to as OMT/GDMT. In our analysis of symptom- lesions significance at least 30% of BFL are eligible for exclusive medical management.(FFR & IFRs ? Less we say about it, is better!) 

8. One more option for those patients (&cardiologists) who wants to travel the middle path is POBA or a Glorified POBA ie DEB  (Ref  Corballis NH,. PLoS One. 2021)

Whatever the treatment, bifurcation PCI  cannot be taken lightly. One exclusive club is debating this topic in Europe every year (EBC) for the past 10 years. Currently, Double kiss and crush (DK crush) is considered superior to others. Mini crush and Culotte are good alternatives in specific circumstances (Definition 2, NORDIC, BBC 2)

Something about DK crush (Shao-Liang Chen Nanjing, China first modified mini crush to DK crush)

Best video resource for DK crush 

 

In DK crush every step appears to be double. Apart from the double stent, it is a double wire cross, double crush, double kiss, and double POT (or even more). All must happen in a specific sequence. One may add double Imaging (Pre and Post PCI IVUS or OCT) to the list.  Finally and funnily not to miss the realistic possibility of double complications over the provisional strategy.

I am not sure which of the 10 steps in DK crush is most important. When we go through the physics of  BFL intervention it appears, that proper crushing and kissing may be the key to success. Though kissing is an integral part of any two stent strategies, in DK crush it happens in a unique interface between balloons /balloons with a stent and finally between two stents. In fact 

The physics of bifurcation kissing includes balloon hugging diameter, area, and pressure. Added to that is the intervening metal layer.

Can’t take the kissing in a casual manner. The Morino & Mitsuda model tells us more about the physics of kissing. In BFL interventions, kissing can happen with various layers that include one layer of the balloon with a crushed and non-crushed stent, carina. While we are mastering the techniques, we must realize, Kissing is aimed at stabilizing the carinal basement, still, there is a distinct possibility, that what may appear as innocuous kissing may undo all the good work we have done in previous steps. I guess, no harm in missing the final kissing if everything is ok in OCT.

Dr. Anonio Colombo’s take on kissing 

 

Final message

So, we have both simple and complex modalities for BFL. Evidence and experience reveal that 90 -95 % of patients with BFL would be eligible for the easy path. In one sense, we are indeed wasting our energy and resources in tackling this negligible CAD burden located at the summit of the global CAD pyramid with a gigantic base. However, we can feel scientifically happy, that we have gained considerable expertise in tackling complex lesions with multiple stent strategies in recent times. Still, we are far away from a true vision, of what really might follow such a niche & expertise-intensive procedure.

Let us hope, that modern metallurgy in combination with physics & hydrology would ultimately beat Biology.

Reference 

1.Dr Colomo article (For personal use only)

2..Morino Y, Yamamoto H, Mitsudo K, . Functional formula to determine adequate balloon diameter of simultaneous kissing balloon technique for treatment of bifurcated coronary lesions: clinical validation by volumetric intravascular ultrasound analysis. Circ J. 2008 Jun;72(6):886-92. doi: 10.1253/circj.72.886. PMID: 18503211.

Postamble

Does evidence create expertise?

Looking at the whole issue of complex PCI philosophically, no technique may really be superior based on accrued evidence. In fact, when expertise becomes the key determinant, the evidence goes to the background. It is really surprising we are too much dependent on hasty and often biased evidence to ratify our expertise, technique, or hardware. I know, one of my colleagues can cross any lesion with one or 2 wires.

To insist, that a particular technique must be followed may not be academically correct always. It is similar to telling a coach driver in advance when to apply a brake or accelerator when he is negotiating multiple hairpin bends in hilly terrain on a rainy day, based on clinical trials done with different drivers on different routes. Ultimately, the outcome is decided by the expertise of the driver, the condition of the vehicle, the road, and not least, the destiny of the passenger.

Read Full Post »

This paper is to  be presented in the the Forth coming   Annual CSI meet New Delhi  December 2012

Beware of Primary PCI : Is there a Low risk STEMI where  pPCI is potentially contraindicated ?

Venkatesan Sangareddi  . Department of cardiology  . Madras Medical college

Primary PCI has proven to be the best  option for management of STEMI . But it need to be done early,  by an experienced team , in a good facility . It is not the individual expertise that matters !  Any treatment , which has great therapeutic potential  also  carries a hazard . So , these treatments  must be used with caution.  Not every STEMI patient , carry a high risk for death.  In fact , the mortality  in some of the subsets of STEMI  can be as low as 1%. If , a  STEMI patient , with a likely 1% mortality is going to get a procedure with  3 – 4 % ,risk it should (And Must !) raise a validity question  But,this issue is rarely addressed in the interventional summits.

In a case pool of 56  randomly collected primary PCIs from various institutes , the outcome  of pPCI  was analysed .It is a retrospective , observational study .STEMI was graded as high risk when one of the following features  were present and it was “low risk” when none of the feature  was  present ( Second STEMI , Extensive  anterior MI , Class 3 /4 killip, An episode of VT/VF, Complete heart block, Diabetic individuals )  High risk STEMI  constituted 22 patients .The overall in hospital  mortality  was (5/56) 9 % In high risk STEMI it was (2/22 )9.5 % in low risk  STEMI it was 3/34 6.4 % .In the corresponding period 40 patients with STEMI who were treated by only thrombolysis or heparin (If beyond time window ) was used a control . 15 patients  were in high risk In the this group the  mortality in high  risk STEMI  was (3/15 )19% and low risk STEMI  there was nil mortality (0/25) 0% .

There was an unacceptable moratlity  with  pPCI  in the low risk STEMI which fared worse than even simple administration of heparin.These data reveal a dangerous fact , that is , primary PCI does not differentiate in the procedural  risk with reference to the patient profile it deals with .While , it dramatically reduce the risk in high risk STEMI It confers a astonishing risk to low risk STEMI .The exact cause for this risk is not known . Common sense would tell , pPCI is  expertise driven driven while thrombolysis is not .Our analysis also suggest bulk of early hazard of pPCI is also logistics related.

Primary PCI could be  cautiously and consciously avoided  in  patients with  low risk STEMI even if it is technically and academically indicated. This can have a great impact in the overall outcome of STEMI management.It is suggested every STEMI patient need to be risk stratified on arrival.(It is still a mystery , why we do this for NSTEMI and not in STEMI ) . A change in the current PCI guidelines to this effect is to be considered.

Read Full Post »

We do come  across ,  even  senior  cardiologists , who  tend to undermine  the importance  of  poster  presentations in scientific  conferences   (I know a  few ,  who  ridicule it as well  ? ) .

                      Is  it not a meanly  job   for  a  cardiologist  to paste a  poster  and stand  beside  it  for hours  , waiting for scientifically motivated audience !

But , what really matter is the thoughts ,  concepts  and often the hard work   that brings  these  posters to  big league  conferences .

Please remember   abstract posters  must cross the hurdle of  the conference peer review  committee’s scrutiny . Often times   the poster arenas   has  launched  some crazy ideas  ,  transform  them to  great  discoveries.

If   only  , Gruentzig had shied  away from the poster  he famously  pasted on lawns of   ACC  , Annual scientific sessions ,Florida

1975     .  .  .  the    revolutionary  concept  of  PTCA   would still be  in utero  !

Final message

I argue the young  fellows in cardiology to send as many  scientific  abstracts as  possible   in their  national or international  meets  . This is  where the  the future of cardiology lies ! Simply don’t  bother about the critics  .

Read Full Post »

Medical science has grown ( and growing )  in an  astonishing pace. Many of the  inventions  which were  considered as  major break throughs   have fallen on the wayside over the years . Of course ,  quite a few  withstood the test of time .

One of  the great inventions  of last century  is per-cutaneous interventions  inside the human coronary artery .

The concept was first conceived and executed by Andreas  Gruentzig  of  Germany in year 1977.  Now , at-least a  million PCIs  are done every year to tackle  CAD  with greatly  improved knowledge base, evidence ,  hardware,  techniques and expertise .

PTCA  is  an  invention worth a Nobel prize . . .well , that’s what we cardiologists feel. The Nobel committee  seems to think otherwise .

What could  be the reasons ?

  1. PTCA is  simply an extension of an old invention. Already the  inventors  of the  cadiac catheterization were  conferred with  Nobel prize (Forssman, Cournand,Richards)  . Hence , it is a sort of duplication of  invention . If Gruentzig is conferred a Nobel prize  the man who discovered the  coronary  stent (A plaque scaffolding device)  will  argue he too deserve  a  Nobel !
  2. What Gruentzig  did  was  in-fact a fundamental  human  response  by Instinct !  .When you encounter  a mechanical obstruction on the road   just try to overcome it . “Here is an obstruction impeding the blood flow , let  me  remove it”  . He did this  with  a wire and balloon . There is not much intellectual  innovation . It was  delivery of a mechanical force through a wire  .   But what the  Nobel  committee should take it to account is , he did this  in live human beating heart  and  cured of his illness most dramatically avoiding a need for surgery.
  3. Finally  comes the vital question. What is the impact of this invention in the health of mankind. ? How  many lives have been  saved when compared to other modalities to treat the   coronary artery disease ? *.This again is not convincingly answered  especially in    stable angina  , for which Geuentzig  originally developed this modality  . One popular argument  is , in terms of life saved and sufferings  relived oral rehydration  fluid  or penicillin  would beat PTCA most convincingly !

* Another possible reason is ,  the  Nobel medical committee is probably well aware of the  perennial  controversy  about  role of  Medicine vs Surgery vs PCI on the outcome   CAD  and  the  superiority of one over the other !

Final message

Whatever  be the reasoning  ,  Nobel committee has to  rethink .  Cardiologists  all over the world   would definitely  agree  if one man who have  made a  huge difference in their patient’s  life ,  it must be  Gruentzig  .

It is well-known  Nobel prize  is given  for path breaking  research that  break  new grounds like  decoding  cosmic mysteries ,  expansion of universe  , cell signalling ,  molecular mimicry  and the  stuff  like that .

Still ,  Gruentzig  definitely  deserves  a Nobel  solely  for  the novelty  in his  procedure  and in the process it helped  avoid  surgery in vast majority of heart patients.

Reference

http://www.nobelprizemedicine.org/

http://circ.ahajournals.org/content/93/9/1621.full

http://www.nobelprize.org/

Video

http://www.angioplasty.org/video/aghero.ram

http://www.angioplasty.org/video/agcomplex.ram

Read Full Post »

This term is quiet often used in the  main stream cardiology journals  ,  in work places , conferences  , hospitals and even among lay persons . No body bothers to define this terminology.   What exactly this term means ?

It  may  not mean anything  . . . to most  of us  even  as the percentage of inappropriate angioplasty is steadily  increasing over the years .

Picture courtesey : Jupeter Images

What does the term  Inappropriate angioplasty  mean ?

(Choose the correct answer  . . . one or more  may be  true )

A.It simply  means doing  unnecessary angioplasties and has no major implication  to  any one.

B.A form of medical ignorance  or  an unethical act and should be strongly condemned.

C. An acceptable cardiology practice ,  need not be discouraged , as  it improves the quality of life of physicians !

D. A  sure act  of  “error by  commission”   that amounts to   medical negligence .

E.It is a decent term for a major  guideline violation

E. It can be  termed  as medical malpractice as it amounts to harming the patient with or without intention.

Read Full Post »

When  PTCA was introduced  by Gruntzig  in 1977 the whole world was awestruck. All he did was . . . to dilate a coronary stenosis with a balloon. No scaffolding  was ever thought off at that time.  It was a huge achievement .   PCI version 1 was  performed for over  20  years in nearly a million  patients   . Till his death stenting  was  an unknown concept.

When the stents first came in,  it was first used with extreme caution .  From the days of  bail out stenting, it  has evolved  into provisional  stenting, elective stenting ,and  now  what is called  “mandatory stenting”

When  Greuentzig was able to  perfuse the obstructed coronary arteries  successfully  in thousands  of patients  in the 1980s,    with a simple balloon

. . . what is the difficulty for us  to replicate it  in 2011 ?

Unfortunately  advocates of POBA (Plain old balloon angioplasty) are considered  to be  un-scientiifc cardiologists or even carry a risk of labeled as quacks.

But please remember . . . POBA   is alive and doing well  too ,  in spite of the serious threat  it faces from the current generation interventionists  . It  will continue to have an  important role in  many  situations.

1.In patients with multivessel  disease while the  proximal lesion  deserve a stent  , POBA is preferred in distal lesions  to reduce the overall metal load .

2.POBA has a major role to play in Primary PCI .We need to realise  dying myocardium does not demand  for stents. It simply requires  quick and prompt restoration of  blood flow. POBA can achieve this with flying colors in most situations.

3. Further , stenting  may be  difficult in complex lesions   during primary PCI .Experience tells us , it  is  dangerous to prolong the primary PCI  procedure time. Here POBA is the only choice ,  may be assisted by thrombus aspiration. Stenting may be delayed or even avoided in many STEMI patients. . We know there is huge STEMI population with  pure thrombus with no atherosclerosis.

4.Patients  with  co morbid conditions , who are  likely to have a non cardiac surgery in the near future  and those who  can not take antiplatelet  drugs  POBA will score over BMS/DES.

5.Finally a POBA costs nothing . .All it requires is a stiff  balloon . In this recession prone world  and ever increasing incidence of  CAD  , POBA  could be the  answer.

6. Acute recoil in POBA (Sudden deaths in POBA is  a rare event !) are more of a perceived fear rather than a reality. It can be argued stents  are  primarily used  to make  cardiologists job easy and  comfortable.

7.Cost effectiveness of plain balloon verses stenting was never  properly tested .

Final message

When sudden deaths  due to subacute   thrombois in DES population   is accepted with all those attendant  pride . . . why not we accept a risk of  less sinister event  namely the  late onset restenosis with POBA.

This is a funny world . The DES fiasco is driving us towards stent less world and a bio degradable stent is already being projected as new savior.

Meanwhile no  one can kill POBA thats for sure !  It  will  ultimately   be reinvented  with another exotic study  soon !

Read Full Post »

Reporting a coronary  angiogram  may look like child’s play  for most cardiologists. Many do it in less than a minute. (It goes something like this  90 % LAD , 30 % ostial OM1, 50 % mid RCA etc etc ) The famous and meticulous  classification of Ellis and Ambrose proposed  two  decades ago appear largely redundant.

In this review we shall  briefly  debate an eccentric plaque or lesion .

Pathological definition

Pathologically  an eccentric lesion  will have a disease free arc  within an  atherosclerotic lesion.If we apply this criteria most of the plaques appear to be eccentric.

Angiographic definition

In simple terms  eccentricity is  said to be present when the plaque  volume is three times more on one side when compared  to opposite side .

The incidence of eccentric lesion is largely under estimated.  It can be up to 40 % of all lesions.

It has histological  as well as  hemodynamic  significance.

How to measure eccentricity index ?

Ratio between maximum plaque thickness and minimum plaque thickness (Including the media )

Image courtesy modified from Circulation. 1996;93:924-931

In the above figure : The eccentricity index is measured  as the ratio of the maximum  to minimum plaque plus media thicknesses. In the eccentric lesion  the maximum wall thickness measures 2.6 mm, minimum wall thickness measures 0.2 mm, and eccentricity index is calculated to be 5.2.  In the  concentric lesion  the maximum wall thickness measures 2.2 mm, minimum wall thickness measures 1.6 mm, and eccentricity index is calculated to be 1.4.

What are the associations of eccentric plaque ?

Calcification and hard plaques are more common in eccentrically placed plaques.The  most vulnerable point for plaque  rupture or disruption is  the shoulder region between normal and plaque segment.

A long eccentric lesion with over hanging plaque

 

Clinical implications

  • Acute recoil
  • Coronary spasm
  • Mechanical effects : Asymmetric expansion of stent
  • Drug eluting stents

An arc of normal plaque circumference predispose to acute recoil and spasm.this is logical as the normal  arc will have a fully functional  medial smooth muscle  which are prone for spasm.

Does stenting reverse  the eccentricity of plaque ?

It may not .  The drag effect of major plaque mass may either result in plaque prolapse or  asymmetric stent approximation  or even stent crushing effect.

How does the  the stents  elute in an eccentric lesion ?

Stents are not intelligent enough to  differentiate  the plaque surface and normal surface. We  also know these drugs are  toxic to  normal endothelium  and hence  are not welcome in the normal arcs of an eccentric lesion.

Since the drug secretion   is uniform throughout the circumference   it makes the   DES a perfect misfit in eccentric lesions  As  we  realise most of the lesions are pathologically eccentric one can guess the long term  consequences .

Final message

The more we think we know . . . the less  is understood .

The images we see daily in cath labs are too simplistic to make vital decisions .There are  constant innovations coming up but none seems succeed in  imparting  common sense to  majority  us.(Namely  direct plaque intervention can never succeed over a diffuse medical  disease called atherosclerosis  )

A good reference article

http://circ.ahajournals.org/cgi/content/full/93/5/924

Read Full Post »

  • It is a complex PCI procedure meant for  high risk  bifurcation /Trifurcation lesions
  • Two stents are simultaneously  deployed.
  • It aims to prevent sudden acute occlusion of one of the major  branches .
  • It is not an easy procedure , and be used only in rare circumstances .
  • Distal left main and ostio proximal LAD/LCX  is a  classical  example.
  • Navigation can be difficult , only well experienced operators should attempt it.

*Is there a ready made two lumen stent available ?

The image is meant for concept purpose only !

 

It is one of the techniques available to stent unprotected left main

An excellent review  in  ACC intervention journal for unprotected left main .

Click on the Image to reach the article

 


Read Full Post »

Coronary angiogram is probably the commonest invasive cardiac investigation done  world wide. It should run into millions every year. The procedure once thought dangerous  is now performed in few minutes in day care centers . While doing a  coronary angiogram  has become a minuscule task to most cardiologists, interpreting  it correctly remains a huge task !

Many  of the young cardiologists  get fascinated in   doing a coronary  angiogram and hardly spend enough time and mind in interpreting it.

Most of  us  succumb to the popular occulo  coronary reflex and describe a coronary  artery  lesions as though it is a  number game . It is very rarely we use the quantitative angiography tools available  in the machine. We need to meticulously  analyse   the length , morphology , distal flow, thrombus  , collaterals  etc . (FFR a new avatar tries to do some justice )

Calling   atherosclerois   by numbers alone,   such as  50 %  LAD  and 70 %  diagonal    20 % left main  is a huge  insult    to the deadly  & diffuse  disease process of atherosclerosis .We are paying the penalty for it .This is  the fundamental  flaw in our  reporting , that  makes every coronary intervention redundant.We must first  remember  we are looking at the lumen not the wall of coronary  artery.

Coronary  interventions is not about removing obstructions but  regression of  atherosclerosis  load within the coronary artery , prevent progression of it and ultimately reduced cardiac events and improve  survival. It  is obvious, it can not be achieved by wires and catheters alone . At best they can be adjuncts.One can  easily understand  why medical therapy  scores over wires  as it can take care of the overall disease process.

But still  ,  most* of  the  learned cardiology community  considers medical therapy   to be an adjunct to coronary intervention  , which  is  a  gross ignorance at it’s best !

* This is my perception. If  I am proven wrong ,  I am happy our patients  will be benefited !


Final message

Do not reduce  the importance of coronary angiogram   to a  farce  number game !

Do not get excited  by visualizing your patient’s  coronary artery. It may make you richer by few thousands. Realise , what you are seeing in a CAG is a fraction of coronary  circulation.

It is estimated coronary  circulation we visualize  daily in cath lab as epicardial coronary arteries  is less than  2  % of entire cross section of coronary  circulation.

This means we are 98 % blind ! ( or  2 % wise  !) .Spend  adequate  time and  mind to interpret it correctly  , so that logical and useful  ( non ) interventions can  be done .This only can make you a  true cardiac professional and your patients will respect you.


//

Read Full Post »

Life cycle of PTCA : Let us hope it do not become extinct !

Does PTCA  , a great Innovation for mankind,  is facing a threat of  extinction ?

It seems so . . . the stents  are losing its shine  in most situations. A simple evidence  . . . for that . . . can  be found in answering the following question

What drives the extensive research in biodegradable stents now ?

The simple answer is , we are fed up with the metals inside the coronary  artery. We want to get rid of it !

Too much of knowledge , often blunts our senses . Our track record clearly  reveals this fact. We needed a major study INTERHEART to tell the world   that  ,exercise is good and tobacco is bad for heart  !  Now ,we forgot a  simplest solution for  getting rid of  metal inside the coronary artery ,  which  is  “not to implant  the stent”  at all ! (Instead we do billion dollar research for making  bio – absorbable stents ,  which in the first place may not be required in the majority !

Read the related article . Does POBA has a role now ? in my site

The only situation  , where PCI   may  withstand the test of time could be in ACS (Both in STEMI and high risk NSTEMI !) PCI is cosmetic in most of the chronic coronary syndromes .

Final message

Our fight against human atherosclerosis will have to be , by medical means .PCI at best will  provide  a supportive role in selected patient group. It requires lots of common sense  and   scientific ignorance to achieve this.   Risk reduction ,  prevention , optimal   medical therapy  will have to play a dominant role in the next few decades .  This is something similar to the environmental issues we face in protecting our planet .No amount of green industry  will protect  the earth . It requires better social and  behavioral  ethics  from  mankind   and their  rulers !

Read Full Post »

Older Posts »