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Here is a  video recipe  !

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

How do you tackle  In-stent restenosis  (ISR) ?

  1. Deploy another BMS
  2. Use a third generation  DES
  3. No . . . first  generation DES(Paclitaxel )
  4. Consider Plain balloon angioplasty.(POBA)
  5. Refer for CABG.
  6. Fall back on medical management.(Ingloriously  referred to  as  “No option” patient !)

Answer:  Please  note , there is no single response answer for this question .

Instent restenosis (ISR) is   commonly seen with BMS .This is primarily because  we are busy blaming DES  for stent thrombosis  and we do not want to give a double blow to DES .There is a  significant population  roaming with ISR  involving  DES .  BMS is in vogue for nearly 2 decades, hence it is natural to see more of it.  In due course ,  DES  is expected to catch up with BMS  and would lead in ISR as well .

The issues in PCI for ISR

Though any of the above 6 strategies may be appropriate ,the urge to put another stent within the IRS ,  prevails over all other options in most centers. This is more off an Interventionist talent  show off  !

Please remember , the common  principles  must apply in all patients before an PCI  . Simply stated , this  principle involves  assessing  symptoms, residual  resting  ischemia, myocardium at risk  during stress, viable muscle mass etc .Lesion characteristics  should come last in the work up. ( A cardiologist  should not  report  a coronary angiogram  , if   does not  not know  basic clinical parameters.)

It is  good  to have a  rule  that  “reserves  intervention”  for ISR  only if the  patient  has refractory angina. 

Can you promise  relief from dyspnea

Contemplating  PCI for  patients with dyspnea as the main symptom is really tricky one.Unlike angina ,  dyspnoea  can be attributed to so many factors other than coronary blood flow.(Apart from LV EF , Iscehmic MR,  A transient diastolic dysfunction , lung function , volume status, renal function , physical conditioning etc)

Opening  ISR in the belief it would improve LV function is highly questionable even if viability is documented.

What is the most important step in the decision making prior to PCI for ISR ?

* Most important step  in ISR management is  probably  spending  sufficient time ,  involving  experts ,  ” democratically  debating”  the indication and techniques  in your institutional cath conference.

Once you document the necessity of intervention* The following things  are possible .

  1. If  the patient has diffuse in-stent stenosis , especially  the  proximal ones or that  involves  branch points,  it is wiser to refer  them for CABG.
  2. Discreet and focal ISRs can safely be attempted for repeat PCI.
  3. BMS or DES  ?  This  is  debated. Current preference is to use  a DES. (Many feel ,first generation DES -(Paclitaxel)  scores over Everolimus in this situation )
  4. Is POBA  possible for IRS ? Can a balloon do a job where a stent has failed ? . No  body is trying it .Many Feel guilty to  do it .  POBA for IRS is a failed concept without even trying it !  One  way of reasoning  is IRS occurred  only  because stent was  never indicated in the first place  in that  location  and a POBA would have been the choice in the initial attempt itself .So let us not make the second error !  ( May be , if  Gruientzig is alive today ,  might have  used  POBA  for ISR very effectively ! )

Issues for which  we will never ever know the answer !

In future any of the following combination of  stents  will occur in tackling ISR.

  • DES covered  BMS
  • BMS covered DES
  • Two BMSs
  • Two DESs
  • Paclitaxel covered Everolimus
  • Everolimus covered Cypher.
  • Overlapped DES and BMS
  • DES covered beta irradiated IRS
  • Rotablated BMS (Yeh metal crushing !)  followed with  DES jacket !

How does the two metals ,  two drugs in various combinations interact with  the tender coronary  endothelium ?

Endothelium is an endocrine organ. It has  to secrete as  many pro and anti homeostatic molecules (Nitric oxide, endothelin etc).This has to be  kept in mind when we develop newer and exotic devices. Of course ,  we claim our  aim is primarily  to provide  relief  to  our ailing patients , but, as things stand today  , there is a distinct risk of  converting human coronary arteries into corporate playgrounds !

Reference :

http://circ.ahajournals.org/content/100/18/1872.full.pdf+html

Surprisingly it is common !

A .Abandon the procedure call the surgeon for an emergency CABG

B. Open the most critical lesion.*

C.Attempt to open and stent all possible lesions.

D.Send the patient back to CCU for a conventional  thrombolysis or attempt a intracoronary thrombolysis.

Answer : All  can be a right response depending upon the available expertise ,  time window, associated complication and hemodynamic stability etc .

* Please note ,the most tight lesion may not be the culprit artery. Though there is high chance for that  being the culprit , it  can be very deceiving   especially when  there is multi-vessel  CAD with  chaotic collaterals.

The site of lesion and site of infarct can unimaginably remote.  (A traffic snarl at remote flyover  can have its impact  right on the busy commercial street due to diversions ! ).

What will happen if you open  a non culprit artery first mistaking it for a culprit ?

This could lead to  dangerous turn of events as whatever little perfusion the patient was getting through the ill-fated  IRA will be challenged by the fresh diversion  facilitated by non IRA angioplasty. Extreme caution is required.

Emergency CABG  within 3 hours  of MI even though advocated  by few ,  is still considered a risky  way to reperfuse  the heart.(In India  there  is  nothing called primary CABG!)

An energetic interventional  cardiologist would vouch for opening all lesions . Only thing  , he has  to  make sure is  , the patient also has enough energy to withstand  his  onslaught. Never   non culprit lesion if a patient is stable . 0ur aim is not that.If the patient  is in shock or impending LVF one can justify opening  few more lesions  that improve total muscle function which can be vital.

What about fall back on thrombolysis?

This may be seen a defeatist attitudebut  when the aim is  in the  well being of patient ,  there is no defeat or success. If severe  CAD is encountered and both  CABG / PCI  or not an option,  the cardiologist need not feel guilty or  humiliated to refer him back for thrombolysis. (Of course , Intracoronary thrombolysis  is  an option !)

Final message

Primary  PCI  is often made  to  appear ” As  a  kids play”  by many modern  day cardiologists . It is not so.  It requires a team effort. It is  race against time.   Feasibility depends largely on the coronary anatomy. The failure rate of  primary  PCI is often camouflaged .(Currently Success of pPCI is boasted at 95%)   Logically it should include pPCI ineligible anatomy as well . Many still do not understand the real purpose of pPCI.   The aim is to salvage the myocardium  at risk , sure and fast. Never attempt for total revascularisation in an emergency situation however tempting it is !

In young persons with discrete single vessel disease  the procedure is simple and outcome is straight forward. In elderly , diabetic , STEMI on  preexisting CAD,  diffuse  multivessel disease  ,   complex main left,  bifurcation lesions , one requires  lot of brain sense  to provide optimal outcome . Many times that sense includes abandoning the procedure !

Please read a related article in this site  Primary CABG

A man  in his 40s presented with an episode of syncope and followed by recurrent episodes of near syncope.

His ECG showed (See image)

  • ECG shows absolutely no evidence of sinus activity . That is  sinus arrest.
  • He lives by the mercy of his AV node.(“Great  escape” junctional rhythm  ! ) . Please note ,  It  fires at less than its intrinsic rate indicating AV nodal sickness as well.
  • The Heart rate is around 18/mt.

SA node is dead(Sinus arrest ) as evidenced by absent p waves. AV node is sick(Depressed) because the junctional rate is less than 20 /mt.

At what  heart rate a person  would develop syncope and near syncope ?

There is no fixed cut off rate for  syncope. It all depends upon the baseline LV function, his exercise capacity, vascular tone etc.

Most will develop some symptoms at  a heart rate less than  40/mt .

Dizziness occur and 30, syncope is sure  when hear rate  dwindles  less than 20 /mt.

A heart rate of 10-15 circulation tends to stall. But still few men are found alive at this rate.

What is the  risk of this patient dying suddenly ?

Contrary to the expectation SCD is not common in  isolated sinus node dysfunction .

It is more common with AV block. The reason being as long as the AV node is fine it will support the rhythm at least at about 30 or s0.

The cause of death in SND is extreme bradycardia induced phase dependent VT /VF.

Will you do a  EP study for him  ?

No. He  does not require it. He is symptomatic ,  and his  ECG shows  tell- tale evidence for SND with AV node depression.

So the there is not even the  necessity to assess  AV nodal status. But .one should  be aware  , there is a battery of tests for SND evaluation (SNRT, cSNRT SACT, etc*) .These are  done only when diagnosis is in doubt or for an academic purpose in teaching hospital.

What pacemaker will you use ?

  • DDDR
  • AAIR
  • VVIR

AAIR can not be used as we have evidence for AV nodal  slowing .

DDDR may be ideal.  In India we still  use VVI mode extensively . Ventricular pacing always safe when you have no EP facilities.  It makes EP study to assess AV nodal function  redundant.

* In all patients with severe bradycardia , a complete workup for systemic diseases like hypothyroidism and other chronic inflammatory pathology must be ruled out. Drug induced bradycardias can exactly mimic pathological  SND. Recognizing these entities could avoid  inappropriate pace maker implantation for  transient reversible bradycardias.

* SNRT – Sinus node recovery time. cSNRT -Corrected sinus node recovery time .SACT-Sino atrial conduction time.

How common is edema legs in diastolic heart failure ?

  1. Can not occur.
  2. As common as systolic failure
  3. Can occur in significant number.
  4. Rare.

Answer : 4

Response  3  may be  correct as well .

When cardiac failure was originally defined by Framingham criteria many decades ago , the entity of diastolic heart failure was non existent .The classical  triad of edema legs, raised JVP, basal rales invariably meant systolic ,  congestive hart failure. We will , never ever know how many of the Framingham cohort had isolated diastolic  heart failure .

Mechanism

For edema to occur there need to be water and sodium retention .For  sodium and water to accumulate either of the two things should happen (Hypoprotienemia, Lymphatic dysfunction excluded)

  • Increased venous pressure
  • Reduced renal clearing of water and salt.

When both join together edema is classical and full blown.

In isolated LV diastolic  heart failure the raise in systemic venous pressure is less pronounced .So ,  edema legs is less conspicuous. but in any type of failure  the net cardiac index tend to decline at least marginally . Kidneys are the first organ to sense this , and the nephrons  goes for  a huddle and begin to retain sodium and water as if body is going to face severe water and salt scarcity .(It is a false alarm actually ! )

Neuro humoral mechanism is   “Alive and well”   in any heart failure whether it is  systolic diastolic , forward ,backward  etc. so  , edema  can indeed occur  in isolated diastolic heart failure

Please note ,  the classical edema  that occur in restrictive cardiomyopathy , constrictive  pericarditis  are due to severe  impediment  to right sided filling and  elevated the lower limb venous  pressure .

Other important determinants of edema legs.

  1. The baseline renal function.
  2. Intra vascular volume status.
  3. The associated  HT induced vascular  changes.
  4. Serum protein  levels.
  5. Venous tone.(A good venous pump   in conditioned  legs develop edema late )
  6. Integrity of lymphatic circulation.
  7. Subcutaneous fat  density and interstitial tissue resistance.

All can modify the local hydro static pressure .These factors operate in various quantum’s  and for this  reason only selcted few develop  significant  edema in cardiac failure .

Also  read  . Why some patients  with cardiac failure never develops edema legs ?

* Please note , the terms diastolic dysfunction and failure can not be used interchangeably. Dysfunction is often a  echo parameter while   failure is its  clinical counterpart .Both can be dissociated in time ,   failure may never follow dysfunction .Most episodes of diastolic dysfunction is transitory   in nature.


In one of the corporate hospitals  which I visited in my city(Chennai*)  ,  happened  to see a nurse taking blood sample from a patient  who has been  just admitted  in a Hi-tech coronary care unit for UA-NSTEMI.

It included blood tests for CRPs,homocysteine,Apo-lioprpitein B etc . She was  being supervised   by  a capitation fee fed  , just delivered  , neo- medical graduate from a country side medical college.

I asked  her  what for you’r doing these  tests.

                        She said ,  it is  to detect risk of developing CAD.

     . . .I  reminded her , the patient  had already developed full blown CAD .

She was too innocent  to say  ” I do not know all those  things sir ,  my consultant asked  me to do it !

This is how  some corporate coronary unit* functions and   handle their  prized  possession . And every one enjoys it , as science  prevails over common sense !

* Shall  I  name the hospital  ?   . . . No , it would invite trouble  . . . oh ,  what  a  freedom of expression we enjoy  !

Patent foramen ovale (PFO) is the new generation hole in the heart for  21st century  cardiologist. Present in about 20% of population  , would correspond to 140 crore  “man holes”  as  on  2012   in this planet. PFOs are embryological remnants across the inter atrial septum.

These minute  holes measuring few mm  are largely a  benign finding .In the recent  decades , it is being increasingly debated these holes  may  not  be innocent after all .Extensive  use of echocardiography in recent times   has contributed to  the awareness  as well as anxiety.

Evidence  is mounting  linking PFO to

  • Migraine,
  • Stroke and
  • Peripheral embolism.

While the above   observation may be true  ,  the  fact that >100 crore people have this entity   , raises  a serious question ,  as labeling  all of  them as heart disease will create chaos among the already health obsessed   population .

So , the main purpose should be ,  to identify the high risk subsets* of PFO population .(This will be a <5 %  at the most). People with PFO may  carry  a mental  stigma because it is referred to as a hole in  the heart by the  general  public .For many  the sense of living with a hole in heart is often more damaging than the hole itself ! (Incidentally , many develop  migraine only after reporting about this hole !)In a strict sense  PFO  is not a hole , rather  it is a communication it may be tunnel  or  slit like .It is argued physician should avoid calling PFO as a hole .

*What is a significant PFO ?

  • Large PFOs >5mm
  • PFOs that shunt blood
  • PFOs with septal aneurysms
  • PFOs with documented stroke or embolism
  • PFOs with atrial chiary network
  • PFO in  persons with systemic pro-coagulant states (Except probably in  pregnancy )

Final message 

PFO is a common residual congenital  atrial septal  anomaly . Usually  benign  . One can  live with it perfect harmony. Only occasional patients  are  at risk.

So the prime job of cardiologists is to not diagnose and create panic about  this entity. rather reassure  them (Is it better do not reveal to them if it is found incidentally ? Patient empowerment group would call  this a  foul !  I do not support blind empowerment  )

At the same time our main  aim is to identify the  high  risk subsets who are prone for events.

Closure of   PFO with device is required in a fraction . (*By the way ,  if   PFO is really dangerous ,  why It is never an indication for surgical closure ?  )

Reference

Your  search for best information  on PFO  would end here .  Here is  land mark   article  in JACC  by  Hara   also contributed by  Renu Virmani . A US  Japan  combines initiative  : A must read by every cardiologists

http://content.onlinejacc.org/cgi/reprint/46/9/1768.pdf

http://www.anesthesia-analgesia.org/content/93/5/1137.full

Hypertrophic cardiomyopathy(HOCM)  is a relatively common inherited myocardial disease.Since it predominately involves  LV myocardium and we know LV muscle mass is an integral part of  mitral valve apparatus , it is natural HOCM  has a major  impact on   mitral valve function .

The mechanism  of MR in HOCM is attributed to the following .

  • Asymmetric septal hypertrophy (ASH ) related abnormal pap muscle alignment (Geometric distortion  )
  • Exaggerated SAM(AML  is attracted towards LVOT with every systole that tend to  keep the mitral  valve  unguarded and MR results)*
  • Intrinsic abnormalities of mitral valve.
  • Associated MVPS
  • VPDs and Non-sustained VT can result in transient MR
  •  Pacemaker mediated MR (DDD pacemaker was used to induce desynchrony of LVOT vs LV free wall .This  concept  is almost a failed  one now !)
  • End stage HOCM -Left ventricular dilatation

* This mechanism is considered less important ,  as SAM is almost universal in HOCM  but MR occurs in less than 20%  patients with HOCM.

Eccentric MR vs central MR

In HOCM the MR is more often eccentric .This is understandable as the primary mechanism is related to faulty angle of pap ,muscle vs leaflet attachment.

If SAM is primary mechanism jet is directed posterior.

Murmur of MR in  HOCM

Is rarely pansytolic as the mechanism of MR begins to operate well after the systole starts .

Many times it is difficult to differentiate LVOT murmur from MR murmur . Th ever confusing and tentative  maneuvers might help in few shrewd cardiologists.

Issues  during echocardiogram

Very often MR jets are mistaken for LVOT gradient.Ideally two gradients in isolation (or  overlapping each other)  one bell shaped other dagger shaped must be documented.

Please note : LVOT jet is different from MR jet in size, shape, timing and site of maximum signal . Still it is often be confused with one other. Most common reason for this is technical .A careful apical 4 chamber view with well opened LVOT will reduce the error . Never record a HOCM echo without ECG gating . The MR jet may be very trivial in color flow but doppler will still pick the signal well . Realise ,for hemodyanmic reasons MR jet must be always more than LVOT jet.Finally if you get a report a LVOT gradient > 100mmhg in HOCM suspect it to be MR ! More often your suspicion will prove to be right !

Can mitral regurgitation occur in non obstructive HCM ?

Yes , in few . This is due to intrinsic abnormalities of mitral valve .

What happens to MR with surgical correction ? Can medical management  regress the MR ?

It is expected to regress.But many patients don’t. Effect of beta blockers   on MR severity is not studied well.

Management

  • Most cases of MR  do not require specific intervention.Just reassure them.
  • Correction of LVOT obstruction is expected to relieve MR considerably.
  • Intensive beta blocker or calcium blocker can regress the MR.(Negative inotropy)
  • Mitral valve repair may be necessary in few  with re-engineering of pap and chordae .
  • Mitral valve replacement should be a last resort. It  may be highly tempting  .But restraint is warranted. Much  damage has been done by showing undue haste in replacing mitral valve in HOCM

Final message

It needs to be realized whatever we do  for the HOCM patients , the ultimate outcome is determined by the quantum myocardial disarray  the patient has inherited from their parents.The myectomy , the alcohol ablation, mitral valve repair,  DDD pacing , beta blockers all are palliative. Except a few  , most HOCM patients generally live their natural history .

Atherosclerosis is an  inflammatory and degenerative disease of blood vessel.The common  belief is  (Of course , it is a fact ) it  mainly causes vascular obstruction and compromise vital organ function(heart, Brain, Kidney etc)

Here is a different facet of atherosclerosis , A middle aged man  surprised us with this  coronary angiogram .   Instead of obstructing the flow the  coronary vessel begins to dilate. This is due to a medial weakness .(The media for some reason begins to give way rather than proliferate to the atherogenic  stimuli.)

Same patient's RCA

One may wonder why he underwent CAG when obstruction is least expected in such a vessel   !  It was paradox of sorts , this man  in spite of his  wide bore coronary artery ,   was prone for coronary thrombus and one such episode landed him in our CCU . ( Please note both faces of atherosclerosis “obstructive and dilatory” can manifest in the same  vessel in different combination.)

This angiogram may be reported  as any one of the following

  • Diffuse atherosclerosis
  • Diffuse atherosclerosis with focal dilatation  and aneurysm formation
  • Coronary  ectasia

These patients should get life long  medium  intensity  (INR 2-2.5) oral  anti coagulants  for preventing coronary thrombosis.

Watch out for similar aneurysmal changes elsewhere (Renal, Cerebral, Aorta etc )

Counter point

How are so sure it is is due to atherosclerosis ?  Can it be a  congenital coronary medial weakness ?

Your guess is not my guess . . . My vote is for atherosclerosis .

In this politically and scientifically  uncertain world nothing is  in black and white. How can you  expect  EST to behave differently ?

Even as  we  are fully  aware of the  limitations  of EST  ,  it  does not make sense   to categorize  EST result into either positive or negative .

In fact , our  estimate suggests  a significant bulk of the patient would fall in the grey zone  .

It is referred  in various terms by  the reporters of EST .

  • Borderline positive
  • Mildly positive
  • Equivocal
  • Inconclusive

What does all these terms mean to the patient ?

It mans only one thing . . .

Physician  who reports  the  EST    is unable to  conclude whether  his patient has  significant  CAD  or not . It is a dignified way of  expressing  the  limitations .

Many factors may play a role. (See the illustration above )

  • Patient factors : Poor exercise stress levels and conditioning
  • Lesion factors:  Collateralised CAD, treated CAD  can result in partial or mild  changes.
  • Machine factors :Caliberation errors.
  • Interpreter : (Physician ) factors

Error in measurement of ST segment . What is borderline  for  one doctor may indeed be true positive  for the other and vice versa .

How will be the  EST in  a  revascularised  or  medically treated CAD ?

If revascularization is a complete success ,  stress test  would  revert back to normal or it can be a borderline as we have just mentioned.

To our  surprise ,  it may  remain  positive in spite of apparently successful procedure.(Residual wall motion defects , scar mediated  ?)

How to proceed  after this borderline EST/TMT ?

Few options are available for the physician/patient

Talk  with the patient again  , assess the  baseline risk  of CAD   if it is low ignore the TMT result and reassure.

  • Repeat  stress test after  a month.
  • Stress thallium
  • Doubutamine  stress
  • CT angiogram
  • Regular Cath  angiogram* (May be the best , of course it also carries a  risk of labeling  the condition as  mild  CAD / non critical CAD etc )

For the  patient  the  easiest  option  may be ,   self  referral to a different cardiologist .   (Also called second opinion )

Final message

There is indeed an entity called   borderline  EST  . Do not dare to  ignore it  or else  face the consequences .

Read  related articles in this site .

1.Can medical management convert EST positive to negative ?

2. Should every one with positive EST should undergo CAG ?