Sinus Tachycardia Vs. Ventricular Tachycardia (Sustained) on Your Watch ECG

‍Got other questions on Sinus Tachycardia or Vtach? See the Qaly guides on Sinus Tachycardia and Vtach:

• What Sinus Tachycardia Looks Like on Your ECG
• What Vtach Looks Like on Your ECG
• ‍How to Read an ECG: Stanford Cardiologist Explains
• ‍The Ultimate Cardiologist's Guide to the Smartwatch ECG

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Introduction

Electrocardiograms (ECGs) are remarkable tools that let us visualize and understand the electrical activity of the heart. With the advent of the ECG on our smartwatches, we now have a convenient way to keep an eye on our heart rhythms. In this guide, we’ll compare two such rhythms: sinus tachycardia and ventricular tachycardia. Let’s dive in.

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What’s Sinus Tachycardia?

Sinus tachycardia is a condition where the heart beats faster than normal, at more than 100 beats per minute in adults. It’s often a normal response to stress, fever, dehydration, or strenuous physical activity.

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On an ECG, sinus tachycardia is marked by a regular rhythm with a rate exceeding 100 beats per minute, where every QRS complex is preceded by a normal P wave. Here’s more on what sinus tachycardia looks like on your watch ECG.

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What’s Ventricular Tachycardia (VT)?

V-tach, on the other hand, is a fast heart rhythm that starts in the lower chambers (ventricles) of the heart. It often results in a heart rate of 100 to 250 beats per minute, which can be life-threatening.

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On an ECG, VT shows a rapid, regular rhythm with wide and bizarre QRS complexes, often overshadowing the P waves. “Non-sustained” V-tach lasts less than 30 seconds, whereas “sustained” V-tach lasts longer. Here’s more on what V-tach looks like on your watch ECG.

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What’s the Difference Between Sinus Tachycardia and VT?

A comparison of sinus tachycardia vs VT revolves around their points of origin and their potential health impacts. While sinus tachycardia originates from the sinus node and is generally non-life-threatening, sustained VT originates from the ventricles and can potentially be a medical emergency.

While both rhythms feature a rapid heart rate, sinus tachycardia usually occurs as a response to external factors and resolves when the trigger is addressed. On the other hand, sustained VT is often associated with underlying heart diseases and can lead to serious complications, such as cardiac arrest, if left untreated.

Remember, while smartwatch ECGs provide us with convenient and useful insights into our heart rhythms, they are not a substitute for professional medical advice. Always consult a healthcare provider if you notice any abnormalities in your heart rhythm. Stay informed, stay proactive, and stay heart healthy!

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Still Not Sure if It’s Sinus Tachycardia or Ventricular Tachycardia (Sustained) on Your ECG?

Differentiating between sinus tachycardia vs V-tach on your ECG can be tricky. If you’re still looking for help interpreting your ECG further, check out the Qaly app on App Store or Play Store. On Qaly, human experts will interpret your ECGs within minutes, day or night. Try out the Qaly app today!