Consult Doctors. FREE.
Real Doctors, Expert Answers
Connect with Facebook Connect with Google For Doctors
By creating an account, you are indicating that you have read and accepted the DoctorxDentist Terms of Use.
Consult Doctors. FREE.
Real Doctors, Expert Answers
By creating an account, you are indicating that you have read and accepted the DoctorxDentist Terms of Use.
Registration Progress
Step 1: Indicate Topics of Interests
Step 2: Follow Relevant Doctors
What are your interests?
Please select at least 3 interests.
Registration Progress
Step 1: Indicate Topics of doctors
Step 2: Follow Relevant Doctors
Follow your favourite doctors
We found some doctors you may like. Click continue to follow them.
Consult Doctors. FREE.
Real Doctors, Expert Answers
Continue with Facebook Continue with Google


Disclaimer: Any answers provided are for general informational purposes only and is not a substitute for professional medical advice. If you think you may have a medical emergency, call your doctor immediately. Always seek the advice of your doctor before starting or changing treatment.

Continue with Facebook Continue with Google

Disclaimer: Any answers provided are for general informational purposes only and is not a substitute for professional medical advice. If you think you may have a medical emergency, call your doctor immediately. Always seek the advice of your doctor before starting or changing treatment.




























































Heart Stents

Heart Stents

A DxD Session with Dr Nandakumar Ramasami

Ended on Thu Nov 15 2018

Top Answers

Thank you for a very insightful and important question, the answer to which, interventional cardiologists such as myself have been battling with for the last few decades.

Essentially, we can break up your question into three parts:

  1. Significance of the location of the narrowing (proximal LAD)
  2. Significance of the narrowing of 80%
  3. Medical therapy or revascularisation (ie bypass or stent therapy) for the above with no symptoms 

the answers to the queries above are, 

-  1) the location of the narrowing in the proximal part (first third) of the LAD is significant as this artery supplies a large part of the heart muscle on the left side (the working side).  Early studies from the 1980's looking at natural progression of proximal LAD disease noted worse prognosis in such lesions if untreated.

- 2) Any narrowing worse than 50% has been shown to affect flow as seen in perfusion scans (ie blood flow within heart muscle using radionuclides).

-3)  well, there is a large body of evidence out there for both options (medical therapy only vs medical therapy combined with bypass or stent therapy).

As you can guess, there are very strong opinions on both sides. A large meta analysis from 2014 (i.e combining a few trials together - especially when individual trials gave conflicting results) – combined 95 trials in 93,553 patients, & concluded that bypass surgery and angioplasty using new-generation drug-coated stents reduces all cause mortality.  

However, certain trials ie COURAGE and BARI-2D (two among many) supported optimal medical therapy alone, though there were many criticisms of the methodology and analyses. 

I would suggest that IF there is objective evidence of ischemia (which is likely in a 80% lesion), then angioplasty or bypass is indicated for better prognosis. 

Ischemia (poor blood flow due to the narrowing) is ideally assessed either by:
- FFR (i.e Fractional Flow Reserve, in the catheter laboratory, is accurate and it's easy to proceed to angioplasty if required at the same sitting - preferred option) 
- or a Myocardial Perfusion Scan (non-invasive, carries some minimal risk and needs careful analysis) 

Neither of the above is required if the treadmill is positive however. We also need to factor in risk factors and symptoms into the decision making.

As you can see, the discussion and decision to proceed are pretty complex, and better taken after an informed discussion in the clinic. I have added some links below for you to look at, though I am afraid they are somewhat technical.

Hope this is of some help, though I would urge you not to procrastinate.


Dr Nandakumar

Revascularisation versus medical treatment in patients with stable coronary artery disease: network meta-analysis

Medical Therapy With Versus Without Revascularization in Stable Patients With Moderate and Severe Ischemia: The Case for Community Equipoise

1 Jun 2018

Both angiogram and angioplasty procedures are quite safe in this day and age.

But any invasive procedure does carry a small risk. Some of the major risks of the procedure would be risk of heart attack (0.05%), stroke (0.07%), need for emergency cardiac surgery (0.05 to 0.3%) and mortality (0.08 to 0.65%). Bleeding and damage to the artery where we access is between 0.2 to 1%. 

To place the above risk in context, I encourage people to compare angiography risk with the statistical risk of an accident on the roads (here in Singapore is 2.5 fatalities/100000 people in 2016).

Do bear in mind that risk is individualized for each patient and these numbers above are derived from statistical calculations from a large number of procedures over the years.

In practice however, over the last 17 years (I entered cardiology sometime in 2001 in the UK) spent in different parts of the UK and in Singapore I can recall two patients who had mini strokes, no patient undergoing emergency surgery and two patients who passed away (who were both quite ill) during emergency procedures. I do not recall any mortality for any patient undergoing elective procedures.

3 Aug 2018

I would suggest that you keep yourself well informed of the procedure, what it entails on the day, what are the various outcomes and what maybe the adjunct procedures you may need and how long your recovery could take based on the results of the angiography and any treatment on the day. Of course, it would be good if your next of kin is also aware of this information.

On the day of the procedure ensure you are well rested and ask your doctor for anxiety-relieving medication the night before if necessary to ensure a good nights sleep. Ensure that all your medications are taken as appropriate (some medications you may have to avoid and your physician will advise you what these are).

It may be best to not do drastic changes in lifestyle while awaiting the procedure (except stopping smoking). Your cardiac rehabilitation counsellor will be able to advise you of the best way to get back to full active life after the procedure in a safe manner.

3 Aug 2018

There have been many improvements in stent technology but one of the noteworthy changes have been the ability to image better inside the arteries. This is a technique called OCT or Optical Coherence tomography which helps us to visualize upto 20 microns ie almost see the vessel live.

This makes it easier to see the fat accumulation inside the blood vessel and the likelihood of the plaque rupturing and if stenting is necessary. It also helps to ensure that stent placement is optimal. 

Of course, changes in stent designs have also been significant with stents made of alloys with much smaller struts. These stents are able to negotiate tortous arteries better. Also some of the stent layers can be partially be absorbed.

The fully absorbable stents are still undergoing changes in design and are not yet available in a universal way.

In addition, there are also specialized stents which are specially used in arteries with branches.  

Specialised equipment and newer techniques to deal with blood vessels which have been blocked for many years have also improved in leaps and bounds over the last few years.

3 Aug 2018

A coronary angiogram is performed whenever a patient has symptoms such as breathlessness or chest pain on exertion (not always) which usually indicate poor blood flow in the heart blood vessel due to blockages.

This could a non-invasive angiogram (ie CT coronary angiogram) or an invasive coronary angiogram (gold standard test). The modality depends on the risk and if the risk is higher an Invasive coronary angiogram maybe warranted. 

Sometimes the poor blood flow is found during specific cardiac tests such as a treadmill test or exercise echo or exercise nuclear scan in someone with multiple heart risk factors such as smoking, family history, high cholesterol, high blood pressure and Diabetes.

Angioplasty, on the other hand, is performed when a blockage is found during angiogram that is significant enough (depends on the location and severity of the narrowing) to need treatment with stents.

However not all blockages maybe suitable for heart stents and occasionally Heart bypass surgery maybe a better option.

3 Aug 2018

All procedures are carried out after a clinical assessment of risk vs benefit. As mentioned above there is always a risk to any invasive procedure and angioplasties on minor vessels just do not justify a patient undergoing the risk of an coronary angioplasty as some of the risk, though of low frequency, if they do occur can be significantly life altering.

And while treating a severe narrowing in an important vessel has a favourable prognostic benefit (ie prolongs life but this is a hidden benefit) the same does not pply to smaller vessels.

As to the second part of the query, nope - a good house cleaning as such seen on “youtube” videos is not a good idea as if indeed a complication occurs this can vary from life altering to life threatening.

A better option is to undertake the boring but effective method of lifestyle changes such as exercising regularly, eating a healthy diet, sleep well and stopping smoking.

3 Aug 2018

Usually, after a coronary angioplasty, some patients experience a pain called “stretch pain” which can last for a few hours after the procedure provided everything else goes well. This gradually resolves.

In general, if the stent is placed well there should be no further pain. This however depends on a number of caveats i.e:

  • There are no small vessels with blockages that are still present
  • There are branches with have been partially blocked with stents etc.

The partially blocked branches may take some weeks to resolve and for the smaller branches one would continue to adhere to lifestyle changes and medication.

However in a well placed stent in a patient with no ongoing issues, who adheres well to lifestyle changes and medication there should be complete resolution of exertional pain almost immediately after the stent insertion.

3 Aug 2018

There are essentially 3 treatments for blocked heart vessels – ie

  1. Medical therapy
  2. Angioplasty or stents, and
  3. Bypass surgery

However which of these options is most suitable for yourself depends on the presence of the blockages, their severity and location.

In addition other factors such as Diabetes, high blood pressure and high cholesterol also play a part. It is important that lifestyle changes always accompany all of the above three options.

Medical therapy is usually recommended when there are mild fatty thickening in the arteries.

Heart stents or coronary angioplasty is the treatment of choice if the narrowing or blockages are few in number and are amenable to stent therapy. In the current scenario, the vast majority can be treated with stents even with multiple blockages.

Bypass surgery is reserved for those with extensive severe disease especially if vessels have been completely blocked for a long time with severe calcification (though not always) and if the patient has other issues such as diabetes and poor heart pumping capacity.

3 Aug 2018

Yes, coronary artery disease can be treated with lifestyle changes - exercise along with diet/stopping smoking/losing weight and reducing stress.

However in certain kinds of coronary disease (may need both a coronary angiogram and nuclear scan) where there is a severe blockage which is causing impairment of blood flow to a significant part of the heart muscle, it maybe advisable to proceed with heart stent or bypass surgery to prevent a heart attack with poor outcomes including mortality.

3 Aug 2018

It depends on what you mean by a “failed “exercise test.

When cardiologists report an exercise test, we usually look at many factors such as:

  1. Does your heart rate and blood pressure go up appropriately with exercise
  2. How far you are able to exercise (time and distance)
  3. What symptoms you get during the exercise and
  4. If there are any ECG changes during the treadmill test

A change in any of these factors will be classed as a “positive” test through there are formal scores such as “Duke Treadmill Score” which is a weighted index and helps to predict the risk of ischemic heart disease (ie coronary disease or blockages in heart blood vessels).

3 Aug 2018

I would suggest a coronary angiogram through the wrist (or radial approach) may be preferable.

You may find in general that the current crop of cardiologists tend to prefer this route and it has been shown in innumerable studies that the radial approach tends to have better outcomes with less complications even in emergencies (ie in those presenting with sudden heart attacks).

This however is only true for those experienced in this technique.

Do note that approaches through the groin may be better for a select few patients, and your cardiologist should know which approach is best for yourself.

3 Aug 2018

When deciding between medical therapy, heart stents (angioplasty) or cardiac bypass surgery, I take into account the full picture based on factors such as:

  • Clinical presentation
  • Patients age
  • Mental and neurologic status
  • Location and severity of the blockages
  • Symptoms
  • Ability to take long-term blood thinning tablets and
  • Other issues such as diabetes, kidney function and heart failure along with patient expectations and preferences.

I also use validated specific “scores” to help decide the strategy such as “Syntax” score. These scores however, have to be interpreted in context to be meaningful and useful.

When the issue falls in the grey zone however, a Heart team comprising of the patient, interventional cardiologist, cardiac surgeon and often the general or family physician can help arrive at a suitable decision. 

Coronary angioplasty (heart stent) in general leads to quicker recovery as there is no open-heart surgery involved and procedure is shorter. There are certain limitations such as possibility of disease progression inside or around the stent (uncommon with current drug-eluting stents and good technique during angioplasty) and the need to continue blood thinning medication for a longer period.

Cardiac bypass surgery can give long-term benefit when the narrowing is severe and extensive (ie throughout the blood vessel) with diabetes and poor heart function though this has to be considered in context (ie someone with general high risk for surgery such as the very elderly or with a previous stroke) may still be better off with angioplasty.

In many cases, however the angiogram helps in easy decision making and is quite straightforward and an open, transparent discussion helps in decision-making.

6 Aug 2018

Yes indeed, CT coronary angiogram (CTCA) and cardiac MRI are non-invasive but are not as accurate as a “normal” angiogram though the sensitivity can be as high as 96%.

Current guidelines generally recommend using a CTCA when there are:

  1. Symptoms (chest pain, palpitations, discomfort or breathlessness on exertion)
  2. Inconclusive or normal stress tests with ongoing symptoms and a
  3. Low to intermediate probability of coronary disease (ie narrowing or blockages). 

CTCA is very useful to rule out coronary blockages (ie high negative predictive value or NPV) but there is a small risk of false positive test as well.

There is also a small risk of radiation, but the benefit outweighs the risk in appropriate patients and modern CT equipment has very low radiation indeed.

Cardiac MRI on the other hand, does not involve radiation but is still not accurate as CT coronary angiogram in diagnosing coronary blockages and is used more often to diagnose cardiac structural issues such as abnormal thickening of heart muscle, thickened covering of the heart or abnormality in the valves of the heart.

I tend to perform an invasive coronary angiogram or a “normal” angiogram through the wrist (radial approach) as there is a lower rate of complications (the traditional route called femoral route through the groin is seldom used nowadays) and is more comfortable for the patients.

Coronary angiogram is the current “gold standard” and the preferred investigation in high risk individuals (ie severe or ongoing chest pain or other cardiac symptoms, on exertion or even at rest in someone with multiple heart risk factors or in someone with known heart blockages) and especially in an emergency situation in someone suspected of having a heart attack.

However even with coronary angiograms sometimes more information is required and during the procedure I tend to do additional imaging inside the artery as required. This is essentially of two kinds namely, using ultrasound called Intravascular ultrasound or IVUS and the second technique uses light called Optical Coherence Tomography or OCT. This helps to see the artery walls, the fatty plaque, composition of the plaque, and if the plaque is about to rupture and plan stent treatment accordingly. After stent has peen placed these techniques also help to ensure that the stent has been placed correctly and there are no complications as well.

Sometimes I also measure pressure across the narrowing to assess the need for treatment such as angioplasty (heart stents) and this is called FFR (Fractional Flow Reserve).This is especially required if the narrowing is of borderline severity.

We also are able to decide if the narrowing does not need any stents based on the above tests as well and whether medical therapy alone will suffice.

6 Aug 2018

It depends on whether the patient falls in the low, intermediate or high risk category based on:

  1. The severity of the narrowing (we use scores such as modified Duke Score/SYNTAX score etc )
  2. Heart’s pumping ability( by echocardiography) and
  3. Presence of other issues such as blood pressure, diabetes and high cholesterol

It also depends on whether patient is stable and the procedure is an elective procedure, or if the patient has presented suddenly with chest pain or breathlessness which drastically alters the strategy.

We generally use both the clinical factors and angiographic picture to asses the final risk status and the treatment strategy for the patient.

National and International guidelines in general advocate the use of revascularization (heart stent or heart bypass) in the presence of high risk features to improve both survival and quality of life.

As mentioned earlier sometimes we also need to do imaging inside blood vessels called IVUS (Intravascular ultrasound) or OCT (Optical Coherence tomography) along with FFR(pressure measurements) to further classify risk and need for stents or bypass surgery.

The CONFIRM registry looked at around 12000 patients and found that patients with intermediate and high-risk scores lived longer if they underwent revascularization (ie heart stents or heart bypass surgery). In another analysis by Mancini et al, in 5000 patients with diabetes and coronary disease, those who undertook bypass or stents in comparison to medical therapy had lower mortality by upto 24%.  

Some trials such as COURAGE and BARI 2D did not show a benefit of revascularization as compared to OMT (optimal medical therapy) but there were many limitations to the trials including selection bias etc.

Indeed there are many many reviews and meta-analysis which show that in patients with multiple blockages with or without symptoms and poor blood flow to a large part of the heart muscle (ischemia), undergoing revascularization (ie heart stents or heart bypass) significantly improves survival and quality of life.

6 Aug 2018

An angioplasty is performed whenever a patient has symptoms along with risk factors suggesting there is coronary disease (ie heart vessel narrowing or blockage usually due to fat deposit).

Following insertion of local anaesthetic a thin tube called catheter is inserted in the artery in the wrist (through the groin in the olden days, rare now) and threaded upto the heart. This is painless usually as the blood vessel lacks nerves to feel touch or pain though sometimes spasm can occur. Following this dye is injected (again painless) and the arteries can be visualized along with any blockages.

If there is indeed a blockage a wire is used to first cross the narrowing followed by insertion of a balloon (which is folded thin). This is then inflated and pushes the fat to the side followed by insertion of a thin wire mesh called a stent (which sits on a balloon).

The process does not take very long in simple blockages though if the blood vessel is very tortous it can take considerable time.

The balloon is usually inflated for upto 30seconds and you might experience transient pain. Once the stent is in place the catheter, wires and balloon are all withdrawn and atight bandage is applied. We will usually change it to a light dressing after 4 hours and when you leave hospital there may just be a band-aid on the site.

6 Aug 2018

A heart stent should and will last for life. A stent after all, is a wire-mesh scaffold and functions as such. Once a stent has been placed the inner vessel wall (called endothelium) slowly grows over it until it “heals”.

Drug-coated stents ensure that this healing is not too excessive as in the days gone past, this excessive healing would lead to re-narrowing. This healing takes between 3 to 6 months and that is why you need blood thinning agents to keep your blood thin as the stent heals. If not, the stent being a foreign body the blood going past it will clot instantaneously.

As you know, clotting of blood is a natural healing process for all living organisms but has to happen in the right place. Some absorbable stents are there just long enough to let the artery heal and then disappear between 2 to 3 years but not all blood vessels are suitable for these stents.

The first generation bioabsorbable stents have now been withdrawn from general use but  newer, improved versions are expected in the near future. Currently an absorbable stent made of a soft, absorbable metal is available but is only suitable for soft, malleable vessels.

6 Aug 2018

Well, as I say to my patients, putting in the heart stent is just the start of a healing journey. Your real work starts now and it needs a consistent daily effort on your part (not just the first 3 months after angioplasty and then back to the old ways!!)

Simple rules such as eating a good healthy diet, avoiding junk and comfort food, exercising regularly, maintaining an active lifestyle, sleeping well, ensuring less stress in your life (even if it means changing your job) along with regular medication and stopping smoking go a long way in keeping you away from further heart stents or procedures.

For those with diabetes it is crucial that the diabetic control is excellent and the HbA1C is kept as low as possible (diabetic folks will know what this is). You may also have to ensure that your lipid profile is kept as good as possible – ideally LDL should be below 75 and HDL above 40. If you have any other risk factors - ie blood pressure or other abnormal lipids ensure these are treated well too.

6 Aug 2018

While there are many reasons why re-narrowing can occur, recurrence of narrowing can be related to:

  • Patient factors
  • Stent factors
  • Procedure factors

As far as patient factors are concerned, a healthy active lifestyle with good diet, adequate sleep, minimal stress and good treatment of cardiac risk factors will help to ensure that heart stent narrowing does not happen. 

Some stents struts are much thicker and have a certain kind of covering (polymer or drug) which can cause narrowing to recur. However a calcified hard artery will need a stent with stronger strut, while a tortous artery will need a softer more compliant stent, while those with diabetes do better with certain stents.

This decision as to which stent is appropriate is based on the experience of the cardiologist.

A stent has to be opened up to its full extent and should be sitting against the wall with no gap to ensure that renarrrowing does not happen.

I usually tend to use intravascular imaging (IVUS or intravascular ultrasound or OCT/Optical coherence tomography) to ensure that this is the case as it reduces the risk of this happening.

6 Aug 2018

Well the term “stent failure” usually indicates either that renarrowing has occurred or that it has been blocked completely.

Complete blockage can be sudden and  obviously causes chest pain, breathlessness or sweating, chest discomfort and may include all the features of a heart attack.

Re-narrowing on the other hand, usually occurs slowly over time and is marked by return of symptoms such as chest pain or breathlessness on walking. In fact, any of the symptoms you had before the heart stent was inserted can return.

Some cardiologist do perform routine tests like a treadmill stress test after insertion of heart stents while others would monitor for symptoms with regular followup in the heart clinic.

6 Aug 2018

Contrary to what you may have heard the number of stents should be determined only by the degree and extent of any narrowing and also how the procedure unfolds.

Most cardiologists do not know the coronary anatomy before the procedure unless an angiogram has been done prior. While you maybe able to predict one stent at the minimum for the severe narrowing, this is not an exact science and one cannot predict exactly how a vessel will react during the procedure.

When angioplasty is performed, the balloon is inflated and this usually pushes the fat aside with a contained dissection or tear in the layer covering the fatty plaque.

As the stent is expanded, some of the branches may be blocked by the movement of fatty plaque. This can be left alone if the branches are too small, or occasionally needs additional stents as the situation demands.

Also, the edges of the stent placement can need further stents as the narrowing propagates, but this again cannot always be foretold. 

As for more stents, usually the charges are fixed and determined by the amount of time spent inside the lab and the complexity of the procedure and not by the amount of stents. In general if more stents are placed, it usually indicates a more complex procedure and obviously takes a much longer time.

A longer time inside the cardiac catheter laboratory has health implications for the operator, with both exposure to radiation and wearing heavy leads in a standing posture. Given a choice, most cardiologists will want to have less exposure, not more.

As to the optimal number of stents for yourself – it depends on the trust you build with your cardiologist and the belief that he will do his best for you.

6 Aug 2018

In general the number of heart bypass surgeries has been falling globally as heart angioplasty (heart stent) technology has improved in leaps and bounds especially over the last decade.

Surgical techniques have also improved and newer techniques such as off-pump bypass or MIDCAB are available.

However, the reason why angioplasties are more popular are because of the quick recovery and absence of the need for open surgery though there maybe a need for repeat procedures.

Patients however, have been voting with their feet for coronary angioplasty even when aware of both the upside and downside of either option and this is a universal phenomenon.

Bypass surgery has less upstream advantages, but in certain circumstances has a longer-term benefit such as in complex extensive disease in many vessels with poor heart function or diabetes.

This strategy however is not always a given and individual patients may need consideration by the heart team – comprising of both cardiologist, cardiac surgeon, family physician and any other related specialist involved in care, along with patient for deciding the optimal strategy.

6 Aug 2018

I do not know of any suitable longterm less invasive alternatives to angioplasty, bar optimal medical therapy.

There are centres abroad that offer EECP ( Enhanced external counterpulsation) but bear in mind that this is recommended for incessant angina, and is only effective for microvascular disease as adjunct therapy (i.e when the disease is in the small vessels not visible to the eye on angiogram and there is no narrowing or blockage in the larger vessels).

Though its a therapy that has been around for quite sometime, but unfortunately the evidence based on peer-reviewed literature  only supports its use in endstage refractory angina which is not amenable to either angioplasty/bypass or optimal medical therapy.   

I attach relevant guidelines below:-


NICE Guideline: (see page 15 of EECP angina) National Institute for Clinical Effectiveness (NICE) currently states that the evidence for the effectiveness of EECP is weak. Therefore generally speaking it’s no longer recommended in the UK as a treatment for stable angina.  

1.6 Pain interventions Enhanced external counterpulsation (EECP) NICE CG126 states that EECP should not be offered to manage stable angina. A Cochrane review by Amin et al. (2010) investigated the effects of EECP in chronic stable angina or refractory stable angina.

One RCT (n=139) was found examining hour-long sessions of EECP once or twice daily for 35 hours over 4 to 7 weeks versus sham treatment. The authors of the Cochrane review deemed the trial to be of poor methodological quality (for example, exclusion of those with severe symptoms of angina), with incomplete reporting of the primary outcome, limited follow-up of secondary outcomes, and flawed statistical analysis.

They therefore concluded that the evidence for EECP in stable angina was inconclusive. The RCT was originally reported on in 1999 and information about it was available during the development of NICE CG126 when the ‘do not do’ recommendation was made.

No subsequently published studies were found by the Cochrane review and thus the results are consistent with the current guideline. Key reference Amin F, Al Hajeri A, Civelek B et al. (2010) Enhanced external counterpulsation for chronic angina pectoris. Cochrane Database of Systematic Reviews issue 2: CD007219 

AHA guidelines:  

B. Enhanced External Counterpulsation Another nonpharmacological technique that has been described for treatment of patients with chronic stable angina is known as EECP.

EECP was evaluated in a randomized, placebo-controlled multicenter trial to determine its safety and efficacy. Patients (n=139) with chronic stable angina, documented CAD, and a positive exercise treadmill test were randomly assigned to receive EECP (35 hours of active counterpulsation) or inactive EECP over a 4- to 7-week period.

The authors concluded that EECP decreased angina frequency (P<0.05) and improved time to exercise-induced ischemia (P=0.01). Two multicenter registry studies that included 978 patients from 43 centers and 2289 patients from more than 100 centers evaluated the safety and effectiveness of EECP in treating chronic stable angina.

These studies found the treatment to be generally well tolerated and efficacious; anginal symptoms were improved in approximately 75% to 80% of patients. However, additional clinical trial data are necessary before this technology can be recommended definitively.

Europe: class of recommendation is Class IIA (ie not recommended as first line therapy)

6 Aug 2018

When a cardiologist is not able to insert a heart stent, this is usually due to:

  1. Either the artery being blocked for a long time (called a CTO or chronic total occlusion, usually with severe calcification) or
  2. Because the artery is very tortuous and the narrowing is in an area which is difficult to reach

In the first instance, ie CTO, where the procedure has been unsuccessful - one could reattempt the procedure with further specialised equipment, and with experts who have specialised exclusively in opening up such arteries.

In the case of tortuous arteries, it maybe worthwhile reattempting the procedure with specialised kit, and a combination of two operators might also help.

During the initial attempt more often than not the operator is able to partially cross the narrowing even in severely occluded blood vessels and this may help in the subsequent attempt as a channel might open up.
However there is also the possibility that the artery might be damaged during the initial attempt and this can vary from a small tear to something more substantial even necessitating emergency surgery or other bail-out procedures. As with all invasive procedures a severe complication could be life threatening as well. 
However in the case of blood vessels which have been blocked for a long time strange to say even in the event of unsuccessful procedure there maynot be a significant change in patients symptoms or outcome as the heart has coped with the previously occluded vessel for quite some time.
7 Aug 2018

Let me give you a very brief overview of the development in the history of stents before coming to the practical aspects.

In the 1960’s Dr Dotter described the conceptual aspect of angioplasty ie using a device like a catheter to dilate a narrowed artery. Dr Andreas Gruntzig in 1977 performed the first angioplasty procedure in an awake patient and in 1986, the first human coronary stent was inserted in France.

Though the initial coronary stents were largely stainless steel wire meshes, in 1999 the first drug coated stent was inserted by Dr Sousa and in 2002-2004 the first generation stents i.e Cypher and Taxus were approved and brought into general use. Further improvements in technology lead to second and third generation drug coated stents and in 2011 the bio-absorbable stent was introduced.

Currently the latest generation stents are largely made of alloys such as chromium-cobalt or platinum-chromium. These have a layer of drugs coated on them and are stuck onto the stents using “polymers”.

Some stents have non-absorbable polymers and healing takes a bit longer. Some stents have fully absorbable polymers(bio-degradable) and once the drug has been released completely it becomes a “bare metal stent”. There are yet other stents where the drug is stored in small “reservoirs” and is designed to release the drug slowly.

Some stents have special coating inside to “capture” special cells floating in the blood stream and have the theoretical advantage of healing faster. There are stents with no polymer at all, where the drug is sprayed onto the surface. Having a polymer that disappears, along with faster healing inside the stent helps to shorten the duration one has to take blood-thinning agents and is suitable especially for elderly patients and those needing surgical procedures.

There are also stents which continue to expand after they have been implanted. These can conform to the contours of the blood vessel. There are also stents designed to fit blood vessels with large branches.

Of course, the latest developments have been the fully absorbable stents which in theory have the advantage of staying in the vessel when its necessary to keep the vessel open and disappearing in two to three years when the blood vessel has a much larger lumen. However the bio-absorbable family of stents are currently not available for general use. Metallic absorbable stents made of magnesium are available though they maynot be suitable for all blood vessels. 

Stents have also become much thinner over time, with stent struts, ranging from 60 micron as compared to the older generation stainless steel stents which are about 140 microns. There are also different designs of stents making some more strong and yet others, more flexible. 

In short, different kinds of stents with different properties designed for specific situations are now available making angioplasty quite versatile and the choice of procedure in the vast majority of cases.

8 Aug 2018

You need not worry about this aspect at all.  

When I do the procedure I always ensure there is adequate pain relief (they are big on pain relief in the UK and the cath lab sister would always be watching the patient intently and if the patient were to wince ever so slightly the pain medication was topped up immediately).

At most you may feel some initial discomfort when the local anaesthetic is inserted.

Following this the rest of the procedure should not cause any pain at all though the inflation of the balloon can cause transient pain (ie a bit like your angina pain) for about 30 seconds.

Some patients experience pain due to spasm of the artery in the wrist but we can always give medication to open up the artery and relieve the pain.

You should be able to inform the team anytime during the procedure of any discomfort or pain, and your team will give you appropriate medication both for pain and anxiety as needed.

Your cardiologist will also be in conversation with you throughout the procedure so you are aware of what is going on and of course, you can always ask if you are not sure. The aim of the operator is to ensure you feel as little pain as possible and are comfortable at all times.

As for pain postop, well, with adequate analgesia, there should be none. You will have sufficient anaesthetic inserted before the procedure and this should last well after the procedure is over.

With the radial approach the sheath is removed straight away after the procedure and you are up and about as well. You do have a tight bandage on the wrist for about four hours before changing to a lighter dressing and this can cause some discomfort.

If you have the procedure done through the groin you may have to lie flat in bed for upto 4 to 6 hours afterwards with a bandage on the groin and many find this uncomfortable especially if you are not used to lying flat for long periods. A discussion with your team might help to find ways you can deal with this.

8 Aug 2018

I am afraid the evidence does point to the fact that there is a clear advantage both in terms of quality of life and mortality benefit (for instance in those patients who have a narrowing of more than 50% in the left main stem ie the major branch on the left side of the heart, only 50% will survive beyond three years on medical treatment alone). 

Of course mild to moderate narrowing in a small noncritical vessel will neither confer a survival advantage nor cause a dramatic change in your quality of life.

This however is not always easy to predict because certain moderate sized branches can still cause significant symptoms. Decisions for treatment have to be individualized and expectations realistic to avoid later disappointment.

8 Aug 2018

Yes, 100% blocked arteries can be treated and many techniques exist nowadays.

If the artery can be opened up through the normal route of blood flow it is called “antegrade” technique and there are newer specialized kits available for this technique. 

There are also techniques that have been developed in Japan over the years called “retrograde” technique which is a way of going through the blocked vessel in the reverse manner by approaching though other arteries.

Usually when a vessel is slowly blocked to 100% over the years the other arteries start to linkup with the blocked artery through bridges (small blood vessels) called “collaterals”.

However, the angiogram has to be carefully studied to check that these collaterals are large enough for equipment to reach the blocked artery. 

In 100% blocked arteries, however, prior to treatment one has to establish that there will be a benefit from the procedure ie opening up the long blocked artery will help with symptoms by improving blood supply to the heart and improve function.

Currently we use nuclear imaging or cardiac MRI to establish that the heat muscle beyond the blockage is alive and is of sufficient amount to warrant what could be a long and expensive procedure.

One has also be realistic about the chances of successful angioplasty and this can be calculated nowadays with scores such as “J-CTO or PROGRESS-CTO” which indicate chances of success and also outcomes.

8 Aug 2018

Recovery time after an angioplasty is pretty similar in most parts of the globe.

In terms of recovery we generally aim for a 4 to 6 week period to get back to full activity. Usually the cardiac rehabilitation team will come to meet you if you have been admitted with a heart attack and following the angioplasty procedure they will provide guidance on the do’s and dont’s.  

Cardiac Rehabilitation is a structured, holistic, 6 to 8 week program which deals with multiple facets of recovery including diet, psychological counselling to deal with the diagnosis, treatment and its aftermath, return to driving and other occupational activity, safe return to exercise and other practical questions.

If undergoing an elective procedure, recovery is very quick and you can return to normal work in a week (even earlier if you are based in an office but not if it is a highly stressful job).  A general rule of thumb is to start aerobic activity such as walking, say 5 to 10mts daily in your first week and escalate by 5-10mts each week until you are able to reach 60mts with no limitation. The emphasis is always to pace yourself and stop if any symptoms occur.  

There should be no issue with returning to your normal lifestyle of badminton and daily jogs following a complete and successful angioplasty provided there are no other issues.

8 Aug 2018

I would say the chances of being completely  angina free depends on the extent of the disease ie if you have diffuse multiple blockages or one or two critical blockages.

With diffuse extensive disease, while you may improve the prognosis by treating the critical large vessels, the symptoms may still remain as many of the smaller branches may continue to cause symptoms as stents and angioplasty cannot be used in the very small branches and vessels.

Optimal Medical therapy and intensive lifestyle changes help to mitigate or alleviate symptoms in this situation in addition to angioplasty and heart stents. 

With one or two critical coronary stenoses however one should expect more complete relief of angina. 

The main aim of successful angioplasty is both improved survival and quality of life and you should expect a 90 to 95% improvement in quality of life following your procedure provided it is clearly established that your symptoms are caused by the narrowing in the blood vessels i.e a positive treadmill or nuclear scan test and that you do not have diffuse disease.

8 Aug 2018

The coronary angiogram is the current gold standard to establish the degree of coronary artery disease and with experience one can usually determine the stenosis with just “eyeballing”.

However, I do use adjunct imaging inside the blood vessel itself, and this helps to clearly establish the area and character of the narrowing or stenosis in the coronary vessel. 

Evidence from trials clearly show that a narrowing is critical when it approaches 70% as it affects blood flow to the heart muscle. However, we also know that there are areas of the blood vessel filled with fat with a very thin covering layer, liable to rupture, called the “vulnerable” plaque, which is not visible on the angiogram.

This thin layer can burst and cause blood to clot, stopping the flow of blood and ultimately a heart attack. These vulnerable plaques can be seen with OCT or Optical Coherence Tomography which can visualize the inside of the arteries with a resolution of upto 20microns. There are other newer techniques on the horizon to identify such “vulnerable” plaques in a routine manner but this is still some way off being applied on a routine basis.

However even the “70%” rule does not always hold and sometimes even 40-50% narrowing can be significant in certain critical coronary vessels such as the left main stem or proximal left anterior descending artery and affect survival.  In borderline narrowing the operator’s experience comes into play and this maybe when other techniques such as the above techniques such as intravascular imaging (IVUS or OCT) or pressure gradient measurement (FFR or Fractional Flow reserve) maybe necessary to determine the significance of the narrowing.

8 Aug 2018

Yes we do use devices occasionally to remove/shave/excise plaques but this is used in less than 5% of coronary angioplasties at present.

The current devices licensed for plaque removal usage in the heart are called:

  1. Rotablator (a nickel plated brass burr with microscopic diamond crystals on it rotating at high speed) which excises the hard plaque tissue
  2. Excimer laser (which uses high energy light to dissolve plaque without harming healthy tissue) and
  3. Orbital atherectomy (which uses a diamond coated crown rotating at high speed to kind of “sand ” the calcium away).

As highly calcified vessels are seen in about 8-10% of all angioplasties I would think the use of these devices will increase in future.

However due to cost, need for time to setup the device and higher complications in inexperienced hands, these devices are not always used.

In the majority of cases when a stent is deployed with a balloon the fat is literally “squeezed” between the outer wall of the blood vessel and the stent and over time is gradually resorbed while the inner lumen is kept enlarged by the stent scaffold which is covered by the inner layer of the blood vessel over 3 to 6 months.

8 Aug 2018

Your father can rest assured that after a successful heart angioplasty he can look forward to a good quality of life and longevity provided that the coronary disease fits the criteria and the coronary angioplasty is technically sound and complete. 

Some simple rules to follow after the coronary angioplasty procedure are – ensure full compliance with the medication especially the blood thinning agents.

Usually two blood thinning agents are given and these should be taken meticulously every day without fail.

Even missing a single dose can cause complications especially in the initial 3 to 6 month period when the heart stent is still “healing” and on no account should they be stopped unless discussed directly with the interventional cardiologist or if life threatening bleeding or other emergency occurs. 

As to the other medication, these have to be titrated up to ensure that cholesterol/LDL/HDL and glucose levels are at optimal levels and your physician will be able to advise you on what the target levels are. Blood pressure has to be well controlled and diet also plays a crucial part.

Also it is important that you address factors such as having adequate sleep and less stress in life in general. Physical activity is very important and has the added advantage of helping to reduce stress, blood pressure and weight.

In the initial stages following the procedure it is advisable that activity or physical exercise is undertaken with a qualified cardiac rehabilitation physiotherapist who is adequately trained and has the necessary equipment in the area of exercise.

8 Aug 2018

NO – heart stents cannot be removed for any reason except in the extremely case of a stent getting infected (about 17 or so cases reported since 1986 when the first stent was implanted and of course millions of people have had stents since then).

In which case heart surgery is necessary along with antibiotics but this is so rare that neither myself nor any of my colleagues over the years (almost 17 years) have seen an infected stent.

Stents cannot be removed because they are essentially a wire mesh scaffold for the artery to heal onto. Once the balloon inflates pushing the artery wall to a larger lumen, the stent inflates with the balloon and as the balloon deflates the stent stays up holding the artery wall.

The inner layer of the artery slowly grows over the stent (called endothelialization) and if you were to look at the artery from inside the lumen, say after a year you may not be able to identify the stent easily. This healing of course is essential as the blood thinners can then be reduced.

Of course you may wish to consider the metallic absorbable stent currently available but this stent is not suitable for all kinds of blockages as it is made of a softer metal and the strut thickness is somewhat large.

8 Aug 2018

Yes, those with diabetes have a two to fourfold risk of developing Coronary Artery Disease (CAD) and the extent and severity of CAD depends on the duration of diabetes. Whether the extent of coronary disease will warrant a stent or other treatment depends on the results of the coronary angiogram. 

As to improving the chances of not needing stents or other intervention, while it has been shown that intensive lifestyle modification and medical therapy helps to prevent and mitigate the progression of diabetes, and also helps in modifying surrogate markers such as lipids (LDL, HDL) and hypertension etc to a favourable profile (and therefore less cardiovascular events) this may not have much impact on established CAD.

You may want to refer to a most recent trial that followed up diabetic patients for upto 9 years(see below). This is only one of many trials available in the literature.  In general, we need to look at a time span of from 4-5 years and sometimes up to a decade or more for lifestyle intervention to make a difference however

As for heart stents, the blood thinning therapy can be cut short from 1 month to 6 months based on the need for surgery with many current generation stents.

11 Aug 2018