Brief Answer:
please see details.

Detailed Answer:
Respected sir
1. The heart beat which comes normally at regular interval for 3 beats and then stops and repeats itself in the same manner, indicates a rhythm disorder of the heart.
2. As I read, in one of the discussions you had on this forum about 4 hours back, your average pulse rate is ~60-70 beats per minute and you have no chest pain or breathlessness. Beside these two symptoms, there are other important symptoms of heart rhythm disorder. These include blackouts, transient loss of consciousness, dizziness or unexplained fall. Any of these indicate that rhythm disorder is serious and need immediate attention of your physician. However in absence of these warning signs, we need to know the exact rhythm of your heart during these abnormal beats. This can be simply done by an EKG (electrocardiogram or ECG). Most of the time, these missed beats turn out to be premature contractions in asymtopmatic patients. In such cases next step is to get a cardiac ultrasound (Echocardiogram) done. If that is also normal, these premature contractions are considered benign and ignored.
3. Premature contractions can be present in anyone and at any age. They are common in general population and in absence of structural heart disease and associated serious rhythm disorder, they are considered harmless. Coffee, tea, smoking, alcohol, certain medicines, anxiety or any physical/ mental stress can provoke them. Only 50% stenosis in right coronary artery is not likely to have any physiological effects.
Hope this provides you some insight into the issue. Now next logical step is to simply get an ECG on priority and ascertain the rhythm of heart. If it is found to be premature contractions, there is nothing alarming, as you had a normal ECHO in recent months.
sincerely
Sukhvinder

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