Beating heart coronary artery bypass surgery (off pump bypass surgery)

What is bypass surgery?

In simple terms, bypass means creating an alternative channel or route for blocked or interrupted channels. Our heart has a network of pipes on its surface to provide blood supply to the heart muscles. These pipes are known as arteries in medical terms. If any of these arteries are blocked, then the blood supply to the heart muscle is interrupted or reduced. To restore the blood supply utilising surgery, a bypass channel needs to be created. The surgery for creating the bypass channels is known as bypass surgery where pipes from other parts of the human body are used to create bypass channels on the heart to restore blood supply to heart muscles.

What is beating heart coronary artery bypass surgery (off pump bypass surgery)?

Traditionally, for most heart surgeries, your heart surgeon needs to stop the heart, and to do so he needs to use a heart lung machine. The heart lung machine has the advantage of taking over the job of the heart and lungs while heart surgery is being carried out.It keeps the human body and its vital functions intact. However, there are certain drawbacks that include very high levels of body inflammation, fluid retention, reduced perfusion to the kidneys and other organs, damage to blood cells and stroke. With advancing technology these side effects are minimal but not completely eliminated. Specialist beating heart surgeons undergo training to carry out bypass surgery without using the heart lung machine thus avoiding /minimising the side effects resulting from it. With this method, the patient’s heart continues to function as normal while the specialist heart surgeon and his team carry out the bypass.

 

What are the advantages of beating heart bypass surgery?

There have been several studies done to understand the benefits of beating heart surgery over surgery where the heart is stopped. The results of these studies have been criticised because of the design faults and limitations. The majority of these studies have failed to show any significant benefits however, it is now widely recommended that if beating heart surgery is done by expert surgeons specialising in beating heart surgery then the outcomes of bypass are equal to standard outcomes, with added benefits of beating heart surgery.

Dr Joshi has performed over 1000 bypass surgeries on the beating heart with excellent outcomes. He has also presented his results in the National conference in Australia. Dr Joshi prefers beating heart surgery mainly to avoid/minimise major stroke which has been clearly demonstrated in his results.

The benefits of beating heart surgery are :

  •         Reduced risk of stroke
  •         Reduced risk of kidney injury,
  •         Reduced requirement of blood product transfusion
  •         Reduced risk of sternal wound infection.

Dr Joshi examines the aorta with ultrasound  in every patient to identify areas which may have a badly damaged wall. He is able to avoid manipulation of a diseased aorta to minimize the risk during bypass surgery. His ability to perform bypass surgery without disturbing high risk areas of the heart confers the major advantage in patients with diseased aorta,which can have a very high risk of stroke (No aorta touch technique). Not all surgeons use these methods as they are a specialised area for beating heart surgeons.

What are the side effects of beating heart bypass surgery?

In the hands of specialist off pump surgeons the side effects of bypass surgery are similar or slightly lower than conventional bypass surgeries that include reduced risk of stroke, kidney impairment, anaemia and infection.

 MIDCAB( Minimally invasive off pump bypass surgery )

How is the surgery performed?

Surgery is performed under general anaesthesia. The patient is prepared like any other major cardiac surgery with insertion of monitoring lines and urinary catheter. Exposure of the heart requires a sternotomy that is splitting of breast bone. Dr Joshi and his assistant surgeon will harvest pipes (Internal mammary artery/radial artery/saphenous veins) during the initial half of the operation and the rest of the operation involves performing  bypass surgery on the beating heart without support of the heart lung machine. Blood thinner is administered at half dose prior to the start of the bypass surgery to ensure that the bypasses don’t get clogged with blood clots.

Heart moves very briskly and powerfully with every beat. Dr Joshi uses a special device (Octopus Stabilizer) that has a mechanism to stabilise the small localised part of the heart during surgery.   Once the bypasses are performed, a special drug (Protamine) is administered to reverse the action of the blood thinner that was administered prior to performing bypasses. During surgery, Dr Joshi uses a Cell Saver device. Cell saver is a technology that is used during surgery to salvage blood cells and transfuse them back to the patient thereby reducing the need for blood transfusion. Chest closure is performed at the end and the patient gets transferred to ICU. Most patients are in an induced coma after surgery. 

What is minimally invasive beating heart bypass surgery(MIDCAB)?

This approach was previously known as MIDCAB (Minimally invasive direct coronary artery bypass). This is also beating heart bypass surgery performed as a minimally invasive procedure.

Minimally invasive bypass surgery involves exposure of the heart by an incision on the ribs rather than the sternum. In this technique, Dr Joshi places approx. 7 cm incision  on the left side of the chest under the left nipple. The main advantage of this type of surgery is that the breast bone remains intact unlike conventional bypass surgery where the breast bone needs to be divided. Dr Joshi introduced this surgery with a small incision to Perth in 2018. He has subsequently presented and published his experience.

With this method, Dr Joshi prefers to perform single bypasses. The other advantages are quicker recovery, minimal blood loss and cosmetically attractive.

One of the side effects of this approach is rib injury or fracture that may cause chronic pain. Fortunately, this is an uncommon side effect. 

Typically most patients are kept asleep with medications for 3-6 hrs to observe for stability. While you are asleep you will be breathing with a breathing machine. The ICU specialist (Intensivist) is in charge of your care while you recover in the ICU. When you wake up you will feel very sleepy and weak. You will notice a few lines , tubes and wires connected to you which are routine. You will feel a bit uncomfortable with all those attached to your body. The additionals are removed as you progress in your care and most are removed by day 5. As a routine, you will be helped to get out of bed and sit in a chair for a few hours to help your lungs breathe better. A physiotherapist will take you for a short walk on day 2 in the ICU. Stay in ICU is typically for 2 days. You will be transferred to the cardiac ward for further care.

Pain is very subjective but overall its uncommon for patients to experience severe pain. You will be given strong pain killers some of which may have unpleasant side effects like nausea, vomiting and constipation. Nursing staff will manage your pain medication in close collaboration with you. You are encouraged to notify staff if you your pain is unbearable, prevents you from deep breathing or keeping you awake.

Pain is very subjective but overall it’s uncommon for patients to experience severe pain. You will be given strong pain killers some of which may have unpleasant side effects like nausea, vomiting and constipation. Nursing staff will manage your pain medication in close collaboration with you. You are encouraged to notify staff if your pain is unbearable, prevents you from deep breathing or keeps you awake.

Progress in ward

You will be in a room once you arrive in the ward. You will be connected to a monitor so nurses can see any alarming signals from your heart rhythm. You need to be careful that the wires remain attached to your body properly. If they get detached, you should inform your nurse by pressing the call button. Most important thing in the ward is to start getting more mobile. You will be asked to walk 5 times every day and your physio will teach you exercises. You may have some wires connected to you which will be removed in the next few days. Removal of wires and lines are very tolerable. By day 5-7, you will be asked by physiotherapists to complete two flights of stairs. This is done to assess your fitness to be discharged home and your independent mobility. You will have a regular blood test and chest x rays. Electrolytes are frequently replaced with intravenous infusions. 

Going home

Most patients are expected to be discharged between 5-7 days after surgery. You will receive discharge education from your nurse who will give you information about incisions, dressing, shower etc. A pharmacist will visit you to discuss your medications which might have changed a little bit. You must remember to take your discharge file with you that should include all your instructions regarding follow up appointments, medication list and other material. You should carry this file with you when you visit your cardiologist or cardiac surgeon for follow up at 4-6 weeks

 

Dressings

You will have a long dressing on your chest. You should remove it after 4 weeks under a running shower. You can remove it earlier  if it starts to come off or breaks. If you have any concerns about the wound please visit your GP or notify Dr Joshi.

You may have incisions on your legs or forearm. It is normal to experience swellings in the legs particularly from where the vein is taken. You should keep your legs elevated whenever seated and also wear stockings provided to you from the hospital. It can take a few weeks or months for swelling to dissipate. You may notice numbness on the site of incisions on legs from where the vein was harvested. It is normal and generally gets better with time. It does not hamper any of the function of your limbs. 

Follow up

You should arrange an appointment to see Dr Joshi in 6-8 weeks and your cardiologist in 8 weeks. You should visit your GP within a week after being discharged from hospital

 

Pain is very subjective but overall its uncommon for patients to experience severe pain. You will be given strong pain killers some of which may have unpleasant side effects like nausea, vomiting and constipation. Nursing staff will manage your pain medication in close collaboration with you. You are encouraged to notify staff if you your pain is unbearable, prevents you from deep breathing or keeping you awake.

Generally considered a low risk operation despite complexity associated with it. In the absence of major medical problems most patients have 1%  or less risk of death or major complications. Most important complications to keep in mind is risk of bleeding and stroke, both of which are minimised with beating heart technique but can not be eliminated completely. Post operative bleeding is due to the requirement of delicate suturing in a high pressure part of the heart  and also leaking from breast bone. Stroke can result from any debris including blood clots blocking one of the vessels in the brain. The incidence of bleeding and stroke is expected to be around 1% . Some patients may have elevated risks which are informed and discussed during consultation.

1 in 4 patients can experience irregular heartbeat. This is known as Atrial Fibrillation.  Depending on your situation Dr Joshi may treat that with medications. Atrial fibrillation is not a life threatening complication but if persistent requires to be treated. Younger patients are a risk of developing  fluid build up around the heart. This typically manifests at about 4 weeks. This is reactive fluid and younger patients are more prone. It is not harmful but can make some patients feel short of breath or feverish. If that happens you should present to ED or notify your cardiologist or Dr Joshi. The treatment involves anti-inflammatory medications and in some cases taking the fluid out with a needle puncture or small incision.

Dr Joshi will see you for follow up after 6 weeks and then your long term follow up is organised by your cardiologist and GP.

Patients are expected to return to normal life. You will be provided with a graduated introduction to your normal activity after surgery. You shall also discuss this with a physiotherapist if you have any specific queries.