A ‘silent’ heart-attack has the same cause, process or mechanism, and consequences, yet it’s largely unfelt and unrecognised. Why?

How many times have we seen the depiction of a person in the throes of a heart attack in movies and serials? He clutches the left side of his chest, face contorted with pain, gasps and staggers, and collapses on the floor/sofa…

Actually, not all heart attacks happen so dramatically. A significant number happen so quietly that the patient shows little or no reaction because he/she is not even aware of it! The reason: it doesn’t have typical symptoms and is unrecognised. Unrecognised myocardial infarctions — colloquially called ‘silent heart attacks’ — are fairly common, accounting for 25 to 30 per cent of all heart attacks, say cardiologists. This attack is often picked up by an ECG, a stress test like TMT, or a blood test (which detects the presence of certain hormones) when the person goes for a routine check-up, days, months or even years later.

Some patients might have no symptoms at all, while some have non-specific symptoms of tiredness, chest-pain or breathlessness that are ignored or unrecognised, explain Dr. Ramakanta Panda, Vice-Chairman and MD, Asian Heart Institute, Mumbai, and his colleague Dr. Tilak Suvarna, Senior Interventional Cardiologist .

Misplaced term

According to Dr. Choudary Voleti, Chairman, Cardiac Sciences, Sri Sathya Sai Institute of Higher Medical Sciences, Bangalore and Prashantigram: ‘“Silent heart attack’ is a misnomer. Many patients do have warning symptoms or ‘prodromal symptoms’, unfortunately very atypical — like gastric upset, feeling light-headed or weak — and so ignored. Generally people consider severe chest pain and breathing trouble as signs of an impending heart attack.”

Kolkata-based cardiologist Radheshyam Basu says many such patients recall that, on that fateful day, they did feel some uneasiness in the chest, abdomen or shoulder, which they dismissed as minor or unrelated to the heart. Some patients also recollect feeling comparatively more tired after the same physical activity in the post-attack period.

The most vulnerable are the elderly (those above 65), and diabetics, say experts. But what causes ‘silent’ attacks? Doctors say, all heart attacks happen when blood supply to a part of the heart muscle is cut off by a rupture of the artery’s thickened wall or a clot. Traditional risk factors are the same — hypertension, diabetes, high cholesterol, smoking, obesity, low physical activity. A ‘silent’ heart-attack has the same cause, process or mechanism, and consequences, yet it’s largely unfelt and unrecognised. Why?

Dr. Panda and Dr. Suvarna explain: “Additional reasons for unrecognised heart attacks may be diabetes, atypical symptoms, high pain-threshold, religious beliefs, neurological or psychiatric disorders, alcoholism. In diabetics, absence of chest-pain is often attributed to autonomic neuropathy, leading to a defective anginal warning system, i.e. the nerves carrying pain stimuli to the brain are defective and so the patient is unable to perceive pain.”

Time is vital

One unfortunate consequence is that the patient doesn’t seek immediate treatment, thus increasing damage to his heart and lowering chances of recovery. The interval between commencement of attack and initiation of treatment determines the outcome; sooner treatment starts, the better. A massive ‘silent-heart-attack’ can even lead to death.

So, how does one prevent such attacks? Experts say prevention measures are the same: regular physical activity, low-fat diet, no-smoking, maintaining healthy weight, preventing/controlling diabetes, and preventing high BP. Dr. Panda and Dr. Suvarna also recommend regular blood tests for sugar levels and lipid profile, stress-tests, ECG, and ambulatory ECG monitoring-Holter Test. Dr. Voleti too recommends regular lipid-profile and stress tests and, when indicated, a myocardial perfusion scan. “The elderly and diabetics should particularly be educated about atypical symptoms.”

Many people dismiss possible symptoms because they think doctors and hospitals cost time and money. Or, they dislike the ‘patient’ tag. Some fear embarrassment if their pain turns out to be nothing more than a gastric problem/physical fatigue. But doctors say that it’s better to be embarrassed or to spend some money and time than risk lasting damage to the body.

After the attack

63-year-old K.S. Sharma*, a mild-diabetic, suffered a silent MI diagnosed two months later in an ECG during his routine annual check-up. Besides medication, he was advised:

Refrain from worry, irritability, and sudden bursts of anger.

Make a habit of positive thinking, laugh a lot, and practise yoga.

A low-fat but nutritious diet. Half his meal would consist of salads and some fruits (as he was diabetic, only a bite or two of fruits).

Polished rice, maida, sugar-rich and processed products and deep-fried food were a complete no-no.

Dry rotis, a few spoons of rice, one cup of dal, boiled vegetables, and low-fat curd besides one raw onion and few garlic pieces were advised for lunch/dinner.

No lifting and carrying of heavy objects including his grandchildren, both under five.

Walking for a total of five km every day; morning and evening included.

*Name changed on request.