CABG or Coronary artery bypass grafting is one of the two options of treating coronary artery disease (CAD). The other treatment option is percutaneous coronary intervention (PCI), which includes angioplasty and stenting. We have discussed both processes to an extent, but individually. Both of these processes help improve the blood flow to the heart, however, there has always been an ongoing debate among medical practitioners and healthcare professionals on the benefits derived from both these processes and how CABG is definitely a better option that PCI!
Angioplasty and Stenting
These are minimally invasive techniques done by Cardiologists.
Coronary balloon angioplasty – This method uses a tiny balloon to forcibly open a plaque and widen the artery, enabling normal or near-normal blood flow to the heart.
Stenting – After an angioplasty, a device called a stent is used to keep the arteries open. A stent is a tiny, expandable, mesh-like tube made of alloys. This stent when inserted into the coronary artery expands and pushes back the plaque, keeping the artery wide open.
Pros of PCI:
- It can be performed quickly, and is especially beneficial during a life threatening situation.
- It is less invasive.
- It’s performed mostly with local anesthesia
- It results in a shorter hospital stay
- Stents have proven to yield good results
Cons of PCI:
- PCI cannot be used for all arterial blocks.
- The coronary artery could get injured during the procedure, and it may not be always possible to treat the blockage with this technique. In such cases, patients will require urgent operation.
- Blood clot may form within the stent. Sometimes there may be tissue ingrowth as well, which causes repeat blockage.
- The chances of requiring repeat procedures are higher with stents. The more the number of stents used, the higher are the chances of requiring repeat procedures.
- Chances of patients experiencing an allergic reaction to the stents are also there.
CABG is a procedure to treat coronary artery disease which is caused by Atherosclerosis. During a CABG surgery a blood vessel is taken from a different part of the body, usually the chest (Internal mammary artery – the LIMA and RIMA), leg (Vein), or arm (Radial Artery) and is attached to the coronary artery, below the narrowed area or blockage. This new blood vessel is known as a graft and it provides the blood a new passageway to reach the heart and bypass the block.
Pros of CABG:
- Cabg can be performed for all kinds of arterial blocks
- It is the preferred technique when blocks are multiple and diffuse in nature
- Extremely beneficial for people with diabetes and heart diseases.
- CABG has long term benefits and patients lead healthier lives.
- The incidence of repeat revascularization after CABG is lower than after PCI.
Cons of CABG:
- It is more invasive than PCI
- There are chances of bleeding during surgery, which will require blood transfusion
- Patient has t stay for a longer duration in the hospital
- The recovery period is longer when compared to PCI
CABG or PCI?
For those who have multi-vessel or left main coronary artery disease, those with diabetes and reduced heart function, CABG is the best option as it offers long term benefits. The nature of CAD in our country is such that a majority of patients have multiple blocks and they tend to be diffuse in nature. In such situations, an additional procedure called endarterectomy needs to be performed, wherein the blocks have to be surgically removed before connecting the bypass.
The major difference between CABG and PCI is that CABG is a major surgery. However benefits derived from a CABG surgery are immense.
The major downside of PCI is re-stenosis of coronary arteries, which is significantly higher for patients who opt for PCI instead of CABG. This is especially so, if there are more blocks and if they are diffuse in nature. Re-stenosis generally leads to repeat symptoms and complications, and requires repeat procedures.
While CABG has always remained the procedure of choice, the introduction of second-generation stents has renewed the debate as to which procedure is more effective. Two studies published in NEJM attempted to answer this question while studying multiple patients from different regions – in one study, 880 patients were randomly assigned to PCI or CABG, and in the second study databases of 18000 patients who received either PCI or CABG were compared. The conclusion? According to Dr. Robert Harrington, Stanford cardiologist: “To the extent that the data from these two studies can be relied on, there are clearly trade-offs between the two revascularization strategies that need to be discussed with patients as part of the shared decision-making process. The early hazard of CABG (the risk of stroke) may be unacceptable to some patients, whereas others might want to avoid the later hazards of PCI (the risk of needing a repeat PCI procedure or having a myocardial infarction).”
The Syntax Trial
This study was referenced in the New England Journal on July 14th, 2014. The SYNTAX is the largest trial comparing CABG and PCI in patients (randomly selected), who suffer from complex heart diseases (patients with three or more arteries affected or with left main coronary artery disease). This study’s 5-year data was published and its conclusion was that even though PCI’s treatment results were comparable to CABG, the more complex the CAD, the more the benefits with CABG. This conclusion was a result of tests conducted on 1800 patients from 85 centres, in Europe and North America.
In figuring out a treatment strategy for a patient with CAD, there are a series of concerns that needs to be addressed when selecting the appropriate treatment. However, based on the data made available to us from various studies, CABG is a superior long-term form of revascularization, especially when there is multi vessel and diffuses CAD.
However we would want to stress on the fact that you need to discuss both strategies with the doctors and take an informed decision, one which suits you best, based upon your medical data, your desire and acceptability.