Posted by: wockhardthospitals | August 8, 2009

Primary Angioplasty for Heart Attacks :Time is Muscle

Time is Muscle


Primary Angioplasty is a strategy of care for heart attacks, also known as a myocardial infarct. During an infarct, there is death of the heart muscle due to an acute and abrupt blockage of a coronary artery (blood vessels supplying blood and oxygen to the heart muscle) by a thrombus ( large blood clot). If this flow is not restored to the heart muscle within an hour, irreversible changes occur which culminates in the death of the heart muscle over the next few hours. The dead heart muscle is eventually replaced by scar tissue.


The quality of life of a patient depends on the left ventricular ejection fraction ( the amount of blood pumped by the main chamber of the heart ). This is normally between 55 to 65%. An infarct negatively impacts the the ejection fraction. The closer the ejection fraction is to normal, the better is the long term survival and quality of life.

image source: i.dailymail

image source: i.dailymail

Primary Angioplasty is the preferred form of revascularization ( a procedure to restore blood flow to the affected organ) who present to the emergency department within 12 hours of symptom onset. Ideally, these patients should be treated with primary angioplasty within 90 minutes of their first medical contact in the hospital as a system goal. This is also the preferred option for patients with an acute infarct 12 – 24 hours following symptom onset who continue to have persistent chest pain, for those with failed thrombolysis (breakdown of clots by pharmacological means) and for patients in cardiogenic shock ( an essentially fatal complication of the heart due to inadequate blood circulation). Primary angioplasty, however, is not offered as treatment to patients who have had an infarct more than 12 hours ago and are presently asymptomatic and hemodynamically stable.


There has been a vast improvement in our understanding and expertise in handling these high risk cases. Primary angioplasty offers a rapid, complete and sustained revascularization compared to thrombolytic agents. Essentially, it offers a much wider window of opportunity to recanalize and reperfuse the myocardium and salvage the muscle. Additionally, it reduces the rate of recurrent ischemia (chest pain episode due to reduced flow) and promotes early hospital discharge. The shorter the incremental delay in primary angioplasty, the greater is the survival advantage. This underpins the concept of “Time Is Muscle”.


Technically, the level of operator and support staff expertise required for primary angioplasty is very high. As an infarct related artery is often thrombus laden, one of the challenges in primary angioplasty is to prevent a no-flow / slow re-flow phenomenon. Anti platelet drugs like Clopidogrel are administered at 600mg as a standard of care. Use of adjuvant drugs like a GpIIb/IIIa receptor inhibitor as a blood thinner is now a universal protocol. Aspiration of the thrombus is also attempted but this is not standard practice.


The clinical success of this high-risk procedure refers to the resolution of symptoms and ECG changes following the procedure with brisk flow in the infarct related artery. In experienced hands and in a well equipped center, this rate is well above 90%. This is attributed to certain institutional requirements such as an experienced operator who regularly performs elective and primary angioplasties at tertiary care centers, nursing and technical staff trained and experienced in handling acutely ill patients, well equipped catheterization lab with IABP ( a balloon inserted in the main artery of the body to support the blood pressure and circulation) and resuscitation equipment, staff available 24/7/365, and a standard operating and validated protocol for management.


Primary angioplasty is now a standardized strategy of care with predictable outcomes in experienced hands. As public awareness increases and the concept of ‘Time Is Muscle’ gathers momentum, primary angioplasty would no longer remain an exception in tertiary care centers; rather it would be a universal expectation.


By Dr. Manjeet Juneja,

Consultant Cardiologist

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