January 10, 2018
Ischemic heart disease (IHD) is the leading cause of death worldwide and is one of the major causes of death in India accounting for 24% of all deaths according to statistical data.
Ischemic heart disease results from coronary artery disease (CAD) which occurs due to narrowing or blocks in the vessels supplying the heart.
What is coronary artery disease and how does it develop?
The coronary arteries are blood vessels that carry blood rich in oxygen and nutrients to the muscles of the heart. When these are narrowed due to plaque deposition (usually due to cholesterol) the heart muscle is deprived of nutrients and oxygen leading to symptoms of chest pain (angina) which can be of varying severity and consequences. This is likely to occur at times when the heart needs an extra supply of oxygen with activities such as running, after a meal, stress or in a cold climate.
The plaque buildup starts universally in all individuals at a young age and continues on the inner side of the blood vessels. The rate of progression and the degree of narrowing produced by the plaque is affected by factors like age, gender (males more than females), hypertension, uncontrolled diabetes mellitus, degree of physical activity, unhealthy diet, smoking, elevated cholesterol levels, being overweight and stress among other things.
If the vessel is blocked suddenly it leads to a myocardial infarction (heart attack) where heart muscles die due to lack of blood. This can be life threatening if a large area of heart muscle is affected.
The American Heart Association (AHA) estimates that someone in the US has a heart attack about every 40 seconds. In addition, for patients with no risk factors for heart disease, the lifetime risk of having cardiovascular disease is 3.6% for men and less than 1% for women. Having 2 or more risk factors increase the lifetime risk of cardiovascular disease to 37.5% for men and 18.3% in women.
How is coronary artery disease diagnosed?
A person who has symptoms of coronary artery disease like pain in the chest on the left side, pain in the left arm, jaw or one having symptoms of breathlessness or developing fatigue easily is best evaluated by a cardiologist who after eliciting a history and performing a physical exam may recommend diagnostic tests like an ECG, echocardiogram and eventually a cardiac catherization (coronary angiogram to visualize the blood vessels). Additional tests may be performed as necessary to assess the function of the heart.
What does it mean for me if I have coronary artery disease?
Once a diagnosis of coronary artery disease (CAD) is made there is bound to be apprehension regarding the best treatment available and lifestyle changes that need to be adopted.
Mild degrees of CAD can usually be managed by lifestyle changes like: cessation of smoking, control of blood pressure and diabetes, lowering levels of cholesterol via weight loss, by exercising in order to increase physical activity and in some cases through medications.
This is best done by a physician experienced in the management of the same and who can prescribe medications if lifestyle changes are found to be inadequate.
Certain individuals who have a high degree of coronary narrowing (stenosis) would likely benefit from one of two therapies.
This is a non-surgical procedure wherein a cardiologist passes a wire and catheters (tubes) to access the vessels of the heart. Based on the location and number of blocks the cardiologist may perform a balloon angioplasty to open up the narrowed vessel and then pass a stent in the opened vessel to keep it flowing (PTCA and stenting (PCI)).
Coronary artery bypass surgery (CABG):
This is a procedure that is performed by cardiac surgeons wherein arteries and veins from the patient’s own chest, arms and legs are used to create a new channel of blood flow beyond the blocked vessels (a bypass graft). The new graft provides an alternative channel for blood to flow and thus provide oxygen and nutrients to the heart.
Both interventional procedures and CABG surgery do not remove the plaques in the vessel – they either push them aside (PTCA) or bypass them (CABG). Hence, they do not cure a person of the disease but preserve the heart muscle at risk by providing better blood flow.
Post procedure/ surgery lifestyle modification and medications will be essential to prevent further rapid progression of the disease and prolong the efficacy of the procedure undergone.
Why have I been told that I am only a candidate for CABG and not PCI?
Certain types of coronary artery disease have best results with surgery either due to anatomy not being suitable for stents, presence of multiple blocks (multi-vessel disease especially patients who are diabetic with triple vessel disease), patients with “left main” disease. Various studies have proven that outcomes in the long run are better with surgery for these patients compared to stenting.
What does a bypass procedure involve?
A coronary artery bypass surgery (CABG) is performed to provide an alternative source of blood by bypassing the blocked vessels supplying the heart.
This is done by using arteries and veins from the patient undergoing surgery. The vessels are then stitched onto the blood vessels of the heart to provide an unobstructed source of blood supply.
Conventionally the procedure is performed by splitting the breast bone (sternum) and accessing the heart – veins are harvested from the leg and arteries form the chest wall or the arm for bypass. To minimize the chance of wound infection the vein harvest from the legs is performed by using endoscopic techniques in advanced centers.
Most of the procedures are performed with the heart beating (off pump). CABG surgery when performed by surgeons in high volume centers is relatively safe.
Following surgery, the stay in hospital is for a few days and after evaluation the patient is discharged.
There will be follow up visits with both the cardiologist and the cardiac surgeon to evaluate progress, discuss lifestyle changes and titrate medications to ensure long term success of the procedure.
Minimally Invasive CABG:
Minimally invasive coronary artery bypass surgery (MICS CABG) is a procedure that has been in use for more than a decade in the USA. The bypass surgery is performed through a tiny cut in the chest with the heart beating without cutting any bones.
Since there is no division of the breast bone the chance of sternal osteomyelitis (infection of the breast bone) is minimal which can be a problem in long standing diabetics with wound healing problems. Also, recovery is quicker, return to normal activity is faster with discharge from hospital in a few days.
MICS CABG is available at only a few centers in India and to achieve the best results patients should undergo this procedure in hospitals where surgeons perform the same regularly, safely with good outcomes and on a day to day basis.
Contact Dr Furtado:
Don Bosco Hall Cross Road
Falnir, Mangaluru - 575001
Ph: 0824 - 2422166/ 2422167; Mob: + 91 8105967088