Pulseless ventricular tachycardia (VT) is an atypical heart rhythm that can cause chest pain, fainting, and cardiac arrest. Doctors treat it with cardiopulmonary resuscitation, defibrillators, and certain medications. Without treatment, pulseless VT is fatal.
Pulseless VT is a type of atypical heart rhythm and constitutes a medical emergency.
This article takes a closer look at pulseless VT. It outlines the prevalence, symptoms, causes, diagnosis, treatment, and outlook of this medical emergency.
With pulseless VT, the heart muscles contract very quickly but not effectively. These contractions are different from typical, well-coordinated heart muscle contractions.
Pulseless VT is a medical emergency where the heart does not pump enough oxygenated blood into the organs, including the heart.
Vs. ventricular tachycardia
Pulseless VT is one type of VT. Doctors call it pulseless because the rapid contractions mean that the heart does not have enough time to refill as it beats. This can leave people without a pulse.
VT is an irregular heartbeat stemming from the ventricles, which are the larger, lower chambers of the heart. VT arises when
VT causes around
Estimates suggest VT comprises between 30% and 75% of out-of-hospital cardiac arrests.
Pulseless VT may cause the following symptoms:
Anyone with symptoms of pulseless VT needs emergency medical attention.
Certain electrolyte imbalances can also lead to pulseless VT. These include:
- hypokalemia, which refers to low potassium
- hyperkalemia, which refers to high potassium
- hypomagnesemia, which refers to low magnesium
- hypocalcemia, which refers to low calcium
The following drugs and medications can also cause this condition:
Additionally, the following conditions may also cause pulseless VT:
Doctors can use a range of different EKG results to diagnose pulseless VT. In an emergency setting, an EKG is often the most likely way for diagnosis.
Pulseless VT requires rapid treatment. A 2020 review examined how doctors and other medical professionals treat this condition. The following steps are effective in many cases:
- Step 1: Healthcare professionals use a defibrillator to lower the person’s heart rate with electric shocks. They also begin cardiopulmonary resuscitation (CPR), which involves chest compressions and artificial ventilation, to maintain heart function during the treatment process.
- Step 2: After the third defibrillation shock, doctors pause CPR and inject 1 milligram (mg) of adrenaline and 300 mg of amiodarone. The adrenaline kick-starts the heart, and the amiodarone reduces the heart rate. Doctors then resume CPR.
- Step 3: After the fifth defibrillation shock, doctors inject 150 mg of amiodarone.
After treatment, doctors will continue to monitor the person for signs of further heart rhythm issues.
In people with a high risk of developing pulseless VT, healthcare professionals may recommend preventive treatments, such as medications or implantable defibrillators.
Estimates suggest that if someone develops pulseless VT outside a hospital setting, the survival rate is roughly
Ultimately, the survival rate depends significantly on timely treatment. For example, delaying defibrillation by 2 minutes or more can reduce the survival rate from 39.3% to 22.2%. Delaying treatment for 15 minutes can reduce the survival rate to 5%.
The survival of someone who experiences pulseless VT outside of a hospital can improve through the use of a defibrillator by a bystander. If there is an automatic defibrillator nearby, bystanders can use it by attaching the leads to the person and following the instructions on the machine.
Here are answers to common questions about VT.
Is pulseless VT a shockable rhythm?
Yes. According to health experts, pulseless VT, such as ventricular fibrillation (VF), is a shockable rhythm. This means electrical shocks from a defibrillator can improve both pulseless VT and VF. However, these shocks alone cannot treat pulseless VT or VF.
What is the difference between VF and pulseless VT?
VF consists of unorganized electrical activity without any beating of the heart.
VT involves organized electrical activity, meaning the ventricles are contracting but not delivering blood effectively to the organs.
Pulseless ventricular tachycardia (VT) refers to the heart’s ventricles beating but not efficiently enough to deliver oxygen as necessary. This deprives people of a pulse and can also quickly lead to heart failure, so it requires emergency treatment.
Symptoms of pulseless VT include chest pain, shortness of breath, and heart palpitations. An electrocardiogram can confirm a diagnosis. Treatment involves defibrillation, CPR, and medications such as adrenaline and amiodarone.
The likelihood of surviving pulseless VT is much higher with prompt treatment. Without treatment, the condition is fatal.