Fixing “Unclassified” ECG Results on Your App

Unclassified ECG results usually happen when your heart rhythm doesn’t fit standard categories that your app recognizes. Most unclassified readings are normal variations that simply fall outside the app’s preset parameters.

You can often fix unclassified ECG results by taking a new reading with proper finger placement, staying still, and ensuring good skin contact with the sensors.

What Does “Unclassified” Really Mean?

Think of your ECG app like a librarian sorting books. Sometimes a book doesn’t fit any existing category, so it goes in the “miscellaneous” pile. That’s what unclassified means for your heart rhythm.

Your app analyzes electrical patterns from your heart. When those patterns don’t match its built-in templates, it labels them as unclassified. This doesn’t mean something’s wrong with your heart.

Why Apps Give Unclassified Results

ECG apps use algorithms trained on common heart rhythms. Normal sinus rhythm, atrial fibrillation, and a few other patterns get clear labels. Everything else? Unclassified.

Research shows that consumer ECG devices correctly identify about 85-95% of clear normal rhythms (FDA studies). The remaining cases often get marked as unclassified rather than potentially wrong classifications.

Common Reasons for Unclassified Readings

• Your natural heart rate variability
• Slight movement during recording
• Dry skin affecting sensor contact
• Unique but normal heart rhythm patterns
• Borderline readings between categories

Quick Fixes to Try Right Now

Before you worry, let’s fix the technical stuff. Most unclassified results come from recording issues, not heart problems.

Perfect Your Recording Technique

Place your finger gently on the sensor. Don’t press hard – think of touching a soap bubble. Too much pressure creates artifacts that confuse the app.

Stay completely still for the entire 30 seconds. Even tiny movements can create electrical noise that throws off the reading.

Check Your Skin Contact

Dry skin doesn’t conduct electricity well. Slightly damp (not wet) fingertips work better. You can lightly breathe on your finger or use a tiny bit of water.

Clean the sensor with a dry cloth. Oils, lotion, or dirt block proper contact.

Timing Your ECG Reading

Take readings when you’re calm and rested. Right after exercise, your heart rate might be transitioning between zones, creating patterns the app can’t classify.

Avoid readings right after caffeine, meals, or stressful situations. These can create temporary rhythm variations.

Environmental Factors

Electronic interference messes with ECG readings. Move away from WiFi routers, microwaves, or other devices during your reading.

Cold hands conduct electricity poorly. Warm your hands by rubbing them together before recording.

Understanding Different Types of Unclassified Results

Not all unclassified readings are the same. Your app might show different messages or symbols that give you clues about what happened.

Technical Unclassified vs. Rhythm Unclassified

Technical unclassified means the app couldn’t get a clear signal. This usually comes from movement, poor contact, or interference. These are easy to fix by retaking the reading.

Rhythm unclassified means the app got a clear signal but couldn’t categorize the heart pattern. This might be a normal variation your app doesn’t recognize.

Signal Quality Indicators

Many apps show signal quality during recording. If you see poor signal quality, stop and restart with better technique.

Good apps will tell you if the reading failed due to movement or poor contact. Pay attention to these messages.

App-Specific Solutions

Different ECG apps have different strengths and weaknesses. What works for one might not work for another.

Apple Watch ECG Fixes

Make sure your Apple Watch band is snug but not tight. The watch needs good skin contact on your wrist while you touch the crown.

Clean both the back of your watch and the crown regularly. Sweat and soap buildup affects readings.

Samsung Health Monitor Adjustments

Place your fingertip flat on the sensor, not just the tip. Cover the entire sensor area for best contact.

Keep your phone steady on a flat surface. Holding it in your other hand can introduce movement artifacts.

KardiaMobile App Tips

The KardiaMobile device needs both hands for a complete reading. Make sure both fingers make good contact simultaneously.

If you get frequent unclassified readings, try the alternative electrode placement (fingers on opposite ends rather than same end).

When Unclassified Results Matter

Most unclassified results are harmless. But sometimes they deserve attention, especially if they happen repeatedly or come with symptoms.

Red Flag Combinations

Unclassified results plus chest pain, dizziness, or shortness of breath need medical evaluation. The symptoms matter more than the app reading.

If every reading comes back unclassified despite good technique, mention it to your doctor. You might have a normal but unusual rhythm pattern.

Medication Effects

Some heart medications change rhythm patterns in ways that confuse consumer ECG apps. This is normal but worth discussing with your doctor.

Beta-blockers, for example, can create rhythm variations that don’t fit standard app categories (Mayo Clinic guidelines).

Improving Your Success Rate

You can get better, more consistent results with practice and the right approach.

Create a Routine

Take readings at the same time each day when possible. Your heart rhythm naturally varies throughout the day, and consistency helps you understand your patterns.

Keep a simple log of your readings. Note which ones work well and which don’t, along with what you were doing beforehand.

Practice Makes Perfect

The first few readings often have technical issues as you learn proper technique. Don’t get discouraged by early unclassified results.

Try taking multiple readings in a row (with breaks between). If the second or third reading is classified normally, the first was likely a technical issue.

Alternative Approaches

If you keep getting unclassified results despite perfect technique, you have other options.

Try Different Apps or Devices

Different ECG apps use different algorithms. What one app calls unclassified, another might classify normally.

Some people get better results with dedicated ECG devices rather than smartphone apps. The sensors might be more sensitive or better positioned for your body.

Professional ECG Comparison

If you’re curious about your unclassified readings, ask for a standard 12-lead ECG at your next doctor visit. This can help identify if you have normal rhythm variations that consumer apps don’t recognize.

Reading Type	Likely Cause	Best Fix
Immediate unclassified	Poor contact or movement	Retake with better technique
Consistent unclassified	Normal rhythm variation	Try different app or ask doctor
Occasional unclassified	Timing or environmental factors	Change when/where you take readings

Conclusion

Unclassified ECG results are more common than you might think and usually aren’t cause for concern. Most of the time, simple technique improvements will give you clear, classified readings. Focus on staying still, ensuring good skin contact, and taking readings when you’re calm and relaxed.

Remember that consumer ECG apps are screening tools, not diagnostic equipment. They’re designed to catch obvious problems, not classify every possible heart rhythm variation. If you’re having symptoms or remain concerned about frequent unclassified readings, talk with your healthcare provider. They can help determine if your unclassified results represent normal variations or something that needs attention.

Why does my ECG app keep saying unclassified even when I feel fine?

Your heart rhythm might be normal but fall outside your app’s recognition patterns. Some people have natural rhythm variations that don’t fit standard categories. This is often harmless, but you can verify with a professional ECG if concerned.

Can anxiety cause unclassified ECG readings?

Yes, anxiety can create heart rhythm variations that confuse ECG apps. Stress affects heart rate variability and can cause borderline readings that apps can’t clearly categorize. Try taking readings when you’re relaxed and calm.

Should I take multiple ECG readings if the first one is unclassified?

Taking 2-3 readings with short breaks between them can help identify if the issue is technical or rhythm-related. If later readings are normal, the first was likely a recording problem. If all readings are unclassified, it might be your natural rhythm pattern.

Do different ECG apps give different results for the same heart rhythm?

Absolutely. Each app uses different algorithms and classification systems. One app might call your rhythm unclassified while another identifies it as normal sinus rhythm. The underlying rhythm is the same, but the interpretation varies.

When should I see a doctor about unclassified ECG readings?

See a doctor if unclassified readings occur with symptoms like chest pain, dizziness, palpitations, or shortness of breath. Also seek evaluation if every single reading comes back unclassified despite good technique, or if you have a family history of heart rhythm problems.