Tachycardia (fast heart rates)

Do you experience Fast heart rates (Tachycardias)?

 

What do the patients complain of?

 

The patients tend to complain of episodes of palpitations due to fast heart rates. Some patients may feel giddy or have  episodes of fainting if the heart rates are too fast.

 

How is this condition diagnosed?

The condition can be diagnosed by a electrocardiogram (ECG) which reveals the fast heart rate. Some patients may need to undergo EP study to diagnose this condition.

What are the causes of Fast heart rates?

These can be due to various causes, however, the common one seen are SVT (supra-ventricular tachycardia), AF (atrial fibrillation) and VT/VF (ventricular tachycardia/ fibrillation).

  • SVT (Supra-Ventricular Tachycardia):  These are caused by the presence of an extra electrical connection between the upper and lower chambers. These patients experience intermittent fast heart rates associated with palpitations and lightheadness. The episodes can be highly distressing and limit one’s activities. They can be easily controlled with medications. However, with the advent of new technology, it has become easier to get rid of them and cure the patient of the fast heart rates. The procedure is called EP (electrophysiology) study and is carried out by inserting small catheters via one’s groin upto the heart. The heart is then stimulated to start the fast heart rate and the location of the extra connection is studied. The pathway can be burnt (ablated) by radiofrequency energy in a controlled manner with the help of catheters. These procedures have a good success rate (> 90%) and take around 2-3 hours. The patient can be mobilized after few hours and discharged the next day.

 

  • Atrial fibrillation: This is a disease of the elderly in which the upper chambers (atria) beat at extremely fast rates (400-750 beats/minute). Thus there is no effective pumping of the upper chamber, causing blood to stagnate and form clots which can cause strokes in high risk individuals. These patients need to be treated with drugs called blood thinners to reduce the risk of stroke. In addition, drug therapy is required to prevent the lower chambers from going fast which can be very distressing to the patient or life threatening. Ablation therapy can be offered in some patients in the early form of the disease. The procedure lasts 4-6 hours and are done through the groin. The chances of recurrence are high (around 30%)

 

  • VT (ventricular tachycardia): These are life threatening and are responsible for sudden cardiac deaths. Most of the patients who suffer from these either have blocks in their blood supply to the heart (have suffered heart attacks before) or have low pumping function of the heart. These patients can be controlled by oral medications. However, devices called Defibrillators are implanted to treat future episodes and to reduce the death rate in patients with heart attacks and poor heart function.  These are implanted just like pacemakers except that they have the additional function to detect and shock these dangerous rhythms. In patients with poor heart functions, an extra wire (lead) is placed on the left side of the heart to improve the heart function.