Ventricular tachycardia (VT) вЂ“ In this rare condition, the fetusвЂ™ ventricular heartbeat is faster than the atrial rate.If this irregular heart rhythm is sustained, it places the fetus at increased risk of hydrops.В AFL may be associated with congenital heart disease or chromosomal abnormalities. Atrial flutter (AFL) вЂ“ In atrial flutter, the atria beat significantly faster than the ventricles.SVT is typically caused by problems with the heartвЂ™s electrical system, which sends the electrical impulses that cause the heart muscles to contract, forming your heartbeat. It occurs when both the atria and ventricles are beating greater than 220 bpm. Supraventricular tachycardia (SVT) вЂ“ This is the most common form of fetal tachyarrhythmia.Sinus tachycardia may be brief, due to fetal activity, or it may be persistent and caused by other maternal or fetal conditions, such as maternal hyperthyroidism, intrauterine infections, fetal anemia and fetal hypoxia (lack of oxygen) Sinus tachycardia (ST) вЂ“ In this condition, the fetal heart rate is above 180 bpm but usually less than 200 bpm, with normal conduction (the electrical signal transmits normally from the upper chambers to the lower chambers).There are several types of tachyarrhythmia ranging from mild to serious, including:

Fetal heartbeat