Acute coronary syndrome or heart attack occurs when there is a sudden complete or partial occlusion of coronary arteries thus reducing the blood supply to the heart muscle.
For simplification, let’s divide our discussion into three parts: 1) How does a heart attack occur? 2) What damage does it cause to our heart muscle? 3) Finally and most importantly, how can we save the heart muscle after the onset of an attack?
As we know, any vital organ of our body requires oxygen and nutrients for its survival and the circulating blood transfers oxygen and nutrients. Cessation of the blood supply to any organ means cutting off the oxygen and necessary nutrients and thereby leading to its damage. Similar is the scenario for the heart muscle. Though the function of the heart is to pump the blood for circulation in our body, for its own function it requires oxygen for which it has a system which delivers blood (i.e. oxygen and nutrients) to its muscle. Now, this system of three small arteries (4.5±0.5 to 2.0±0.5 mm in diameter) which supplies blood to the heart muscles is known as coronary arteries. During a heart attack, any one of these small diameter arteries gets clogged up due to the rapid formation of clots, usually in the diseased segment of the artery and thus the oxygen supply to the heart muscle gets cut off. The patient feels severe pain in the chest, upper limbs, back, jaw and neck, more often described as suffocation. Symptoms may differ in the form of mild chest pain on and off or sensation of indigestion/bloating/heartburn or breathlessness. All these warrant full investigations for an ongoing heart attack.
After the onset of heart attack, starting from the inner muscle layer, a process of cell death continues in the heart muscle and within a stipulated time, if no treatment is provided, these damaged muscles are finally replaced by dead scarred tissues. So in the event of chest pain taking proper medical care within the earliest possible time till the heart muscles are viable, is of utmost importance.
Now coming to the third and most important aspect of emergency medical care – the first step being early suspicion of heart attack by the patient himself and then taking immediate medical advice without mistaking it to be acidity. After confirmation of heart attack by a doctor, blood thinners and other required medications are given and then after risk stratification, the patient undergoes an angiography to visualize the blockage in the culprit artery. At present, all over the developed countries like US/Europe, the whole effort is to carry out an angiography and angioplasty at the earliest possible time (within 90 minutes of a patient having severe chest pain) for which in the USA, they have an alternative traffic route for 911 ambulance. The logic is simple – to save more muscles from damage by opening up the blocked artery early. So here comes the new treatment modality of angiography and angioplasty by an Interventional Cardiologist in a heart attack.
During angiography, a hollow tube-like structure is entered into the coronary system from arteries of the wrist or groin through a small 3-4mm puncture. Through the tube, a dye is injected into the coronary artery from outside to see the blockage. This is called angiography, just like an x-ray to see any fracture following an injury. After the angiography, the opening of the blockage is done by Angioplasty. It is an extension of the angiography was through that hollow tube, which was put into the coronary system, a very thin wire is passed across the blockage in the coronary artery. Then over this wire, a balloon is passed across the blockage and inflated to create a passage in the artery. After that, a metallic hollow ring-like structure called stent is placed inside the blockage and opened up so that the blockage gets cleared and the blood flow to the heart muscle is restored thereby putting a break to the ongoing damage. A timely angioplasty of the culprit coronary artery can save almost all the heart muscle involved in the attack thus leaving the patient with no stigmata whatsoever of an attack in the future. This is the most important intervention in cardiology at present. Many clinical trials have proved that compared to medical drugs alone, an angioplasty done during a heart attack is much more superior because of its rapid, complete and sustainable results with survival benefits.
At present in India, angioplasty during a heart attack is being done in big cities regularly but less in smaller cities due to lack of infrastructure and most importantly, due to lack of awareness in general population regarding the best treatment strategies leading to delay in taking decisions. For a heart attack patient, TIME IS MUSCLE. If the initial crucial time is lost, no benefit can be obtained even by receiving treatment later in the highest medical centre of the country or abroad! So, any sudden or recent onset of chest pain should never be taken lightly as delayed diagnosis and treatment of acute coronary syndrome or a heart attack can lead to permanent damage to your heart muscle. This may lead to further problems including recurrent hospital admissions in future due to breathlessness arising out of low pumping power of damaged heart muscles and most importantly, low quality of life due to reduced exercise capacity.
Dr. Ritankur Barkotoky | Consultant: Interventional Cardiologist | Narayana Superspeciality Hospital, Guwahati