Overview
The Inner Balance Coherence Plus is a Bluetooth-enabled ear clip sensor and app system that measures heart rate variability (HRV) and provides real-time coherence feedback. Many people who use it are health-conscious individuals who may also be living with an implanted cardiac pacemaker. This FAQ addresses the most common questions about safe and effective use of the device in that context, covering device technology, electromagnetic safety, placement guidance, and what to expect from the coherence scores.[1][2]
Section 1: Device Technology — What the Inner Balance Coherence Plus Is and Is Not
How does the Inner Balance Coherence Plus measure heart rate?
The device uses photoplethysmography (PPG) — a passive, non-invasive optical measurement technique. A small LED in the ear clip shines light through the earlobe tissue, and a photodetector measures the changes in light absorption caused by the rhythmic pulsing of blood with each heartbeat. This produces an inter-beat interval (IBI) signal, the raw data from which coherence scores are calculated.[3][2][4]
PPG involves no electrical current passing into the body, no ultrasound, and no magnetic fields. It is the same optical principle used in hospital pulse oximeters and fitness smartwatches.
Does the Inner Balance Coherence Plus contain any magnets?
No… The Inner Balance Coherence Plus — including the ear clip, sensor pod, and charging system — contains no permanent magnets in any of its components. This is an important distinction from some consumer electronics (such as phones with MagSafe wireless charging) whose embedded magnets have been shown to trigger “magnet mode” in pacemakers. The concern about magnetic interference with pacemakers does not apply to this device.[5][6]
How does the Bluetooth work, and is it the same as Wi-Fi or a mobile phone?
The device uses Bluetooth Low Energy (BLE), which operates at 2.4 GHz. BLE is specifically engineered for minimal power consumption. Its maximum output power is less than 1 milliwatt (mW) — compared to 250–2,000 mW for a typical smartphone. BLE is hundreds of times weaker than a mobile phone signal and several orders of magnitude weaker than the sources known to cause significant pacemaker interference, such as surgical electrocautery or MRI machines.[7][8][9]
Section 2: Electromagnetic Safety and Pacemaker Compatibility
Can a Bluetooth device interfere with a pacemaker?
In principle, any radiofrequency (RF) device can cause electromagnetic interference (EMI) with a pacemaker if it is operating too close to the implant site. The mechanism is not damage to the device — it is that pacemaker sensing circuitry may occasionally misread external RF signals as intrinsic cardiac electrical activity. This can cause pacing inhibition (withholding a needed pacing pulse) or, in devices with defibrillator function (ICDs), inappropriate mode switching.[10][11]
In practice, the FDA’s assessment is that even mobile phones — far more powerful than BLE devices — “do not seem to pose a significant health problem for pacemaker wearers”. One large clinical study screening 300 pacemaker patients found only a single case of phone-induced EMI. The risk from a BLE device emitting less than 1 mW is, by any current clinical measure, very low.[12][13]
Is there a safe distance rule I should follow?
Yes…The FDA, the American Heart Association, Medtronic, Boston Scientific, and Abbott all apply a universal precautionary guideline: keep any Bluetooth-transmitting device at least 6 inches (approximately 15 centimetres) away from the pacemaker implant site. This distance rule is precautionary and applies regardless of the low power output of BLE devices — it accounts for device-to-device variation in pacemaker shielding and individual differences in sensitivity.[14][15][5]
For cardiologists and electrophysiologists: The 6-inch / 15 cm rule is conservative relative to BLE power levels. The inverse-square law means that RF field strength at 15 cm from a sub-1 mW BLE source is well below pacemaker EMI susceptibility thresholds established by IEC 60601-1-2. The clinical concern for BLE is specifically proximity: EMI has been observed when transmitting accessories are worn or rested directly against the chest, at distances of 3 cm or less from the implant.[7]
Where is a pacemaker typically implanted?
The overwhelming majority of pacemakers are implanted below the left clavicle, in the left pectoral region, just under the skin. A small minority (~1%) are implanted on the right side due to anatomical or surgical factors. Users should confirm the location of their implant with their cardiologist, as the safe-use guidance below is based on left-side implant — by far the most common configuration.[14][5]
What is the risk if the sensor pod is worn hanging at chest level?
The Inner Balance Coherence Plus ear clip is connected to a sensor pod (which houses the BLE transmitter and battery) by a cable. If the pod is allowed to hang freely from the ear, it will rest at approximately chest level — placing it in proximity to the pacemaker site, potentially within or near the 6-inch safety zone. This is the specific configuration to avoid.[16][7]
Section 3: Safe Wearing Guidance
What is the recommended way to wear the device if I have a pacemaker?
Following the 6-inch (15 cm) safe-distance rule, the recommended wearing configuration for pacemaker users is:
- Clip the ear sensor to the right ear. Most pacemakers are on the left side; using the right ear keeps the sensor on the contralateral side.
- Clip or pin the sensor pod to the right shirt collar or right lapel. This positions the BLE transmitter at the right collarbone level — typically 25–40 cm from a left-side pacemaker implant, comfortably exceeding the 6-inch safety margin.[15][7]
- Do not allow the pod to hang freely at chest level. A small clip, safety pin through clothing, or collarbone-level attachment point keeps the pod well clear of the implant site.
This simple adjustment — right ear clip, pod clipped to right collar — resolves the proximity concern entirely for users with the typical left-side pacemaker implant.
Does using the right ear affect measurement accuracy?
No… The PPG optical sensor in the ear clip measures blood volume pulse in the earlobe capillary bed, which is equally accurate from either ear. The coherence score algorithm requires only consistent, clean IBI data; it is indifferent to which ear the clip is on.[17][18][4][3]
Should I still consult my cardiologist before using the device?
Yes…not because the device poses a high risk, but because your cardiologist or electrophysiologist knows your specific pacemaker model, its programmed pacing mode, and its sensitivity settings. They can confirm your implant location, advise on any individual factors relevant to your device, and help you understand what to expect from your coherence scores (see Section 4). Always follow your physician’s guidance over any general product advice.
Section 4: What Pacemaker Users Can Expect from Coherence Scores
Will my coherence scores be affected by my pacemaker?
This depends critically on the type and programmed mode of your pacemaker.
The HeartMath coherence algorithm analyses a 64-second sliding window of inter-beat intervals (IBIs), looking for a smooth, rhythmic, sine-wave-like pattern in the heart rate variability data. A coherence score reflects the mathematical order of HRV — how smoothly and rhythmically your heart rate rises and falls — rather than simply the total amount of variability.[19][17][3]
For coherence scoring to function as intended, the heart must be able to vary its rate in a smooth, rhythmic way under the influence of the autonomic nervous system. Whether a pacemaker allows this depends on its programming mode.
What pacemaker modes are compatible with coherence scoring?
| Pacemaker Mode | Description | HRV/Coherence Compatibility |
| AAI / AAIR | Paces only the atrium; sinus node remains in control | High — natural autonomic control largely preserved[20][21] |
| DDD / DDDR | Dual-chamber; tracks atrial activity and paces ventricle in synchrony | Generally good — atrioventricular synchrony maintained; short-term HRV somewhat reduced[20][22] |
| VDD | Senses atrium, paces ventricle; preserves AV synchrony | Generally compatible — autonomic control of sinus node intact[^23] |
| VVI / VVIR (fixed rate) | Paces ventricle at a fixed rate regardless of sinus node activity | Limited to none — fixed-rate pacing suppresses the beat-to-beat variability required for coherence scoring[21][24] |
| CLS (Closed Loop Stimulation, e.g., Biotronik) | Uses intracardiac impedance to mimic physiological rate changes | Partially compatible — can preserve short-term HRV better than standard DDDR[25][26] |
The key principle: If your pacemaker is only pacing intermittently — activating only when your heart rate drops below its programmed lower rate limit — then your intrinsic sinus node rhythm is in control most of the time, and coherence scoring will reflect your genuine autonomic state. If your pacemaker is pacing continuously (as is common in VVI mode for complete heart block), the device is generating the rhythm, and the software will read the pacemaker’s fixed rate rather than your autonomic nervous system’s activity.[21][24][27]
What will I see on the app if my pacemaker suppresses HRV?
HeartMath’s own guidance notes that in fully paced rhythms, “the [software] will only reflect the pacing done by the pacemaker and therefore will not be able to show change in HRV due to changes in nervous system activity”. In practice, you may see:[24]
- Persistently low coherence scores
- A flat or relatively unchanging power spectrum
- Red “arrhythmia” indicators if your device produces irregular or ectopic beats alongside pacing artefacts[24]
If you see this pattern, it does not mean the HeartMath techniques are not benefiting you — it means the software cannot accurately reflect those benefits numerically. HeartMath recommends that users in this situation focus on the subjective experience of relaxation, emotional balance, and reduced tension during sessions rather than relying on numerical scores.[28]
For cardiologists: Short-term HRV (rMSSD, pNN50, HF power) is most preserved in AAI and VDD modes where sinus node autonomic control is intact. DDD pacing moderately reduces vagal HF power due to altered ventricular mechanics, but maintains meaningful beat-to-beat variability. VVI pacing is associated with sympathetic overactivity, vagal withdrawal, and the virtual elimination of rhythmic HRV oscillations. Rate-responsive DDDR mode preserves long-term but not short-term HRV. CLS-based pacemakers (Biotronik) have demonstrated the best preservation of short-term physiological HRV among pacing modes, though total HRV power remains lower than intrinsic rhythm.[20][25][21]
Can I still benefit from HeartMath techniques even with a low-HRV pacemaker mode?
Yes. The HeartMath app supports HRV measurement using your smartphone’s rear camera and flash as a PPG sensor — a technique validated in peer-reviewed research as capable of extracting HRV parameters from fingertip PPG via smartphone camera. No ear clip, no Bluetooth transmission, and no sensor pod are involved in this mode.[29]
To use this option:
- Download the HeartMath app (available on iOS App Store and Google Play).[30][1]
- Subscribe to the HeartMath app at $79 per year. (Inner Balance Coherence Plus sensor owners receive a complimentary lifetime subscription included with their sensor purchase.)[30][1]
- In the app, select the camera sensor option and place your fingertip gently over the rear camera lens and flash.
Section 6: Summary Guidance for Pacemaker Users
| Situation | Recommendation |
| Left-side pacemaker, standard use | Wear ear clip on right ear; clip pod to right shirt collar to maintain >6 inches / 15 cm from implant |
| Right-side pacemaker | Wear ear clip on left ear; clip pod to left shirt collar |
| Prefer no device near body at all | Use smartphone camera/flash option via HeartMath app subscription |
| VVI fixed-rate pacemaker | Coherence scores may be low or flat — use app for guided practice and focus on subjective experience, not scores |
| DDD / AAI / VDD pacemaker | Coherence scoring will generally function; scores may be somewhat lower than population norms |
| Any pacemaker user | Confirm implant location and pacing mode with cardiologist before regular use |
This document is intended for general informational purposes and does not constitute medical advice. Users with implanted cardiac devices should always consult their cardiologist or electrophysiologist with specific questions about their individual device and programming.
References
- Coherence Technology | HeartMath Institute – Based on 30+ years of research conducted at HeartMath Institute, we offer the emWave and Inner Balan…
- HeartMath Inner Balance Coherence Plus – Elite Recovery Supply – DESCRIPTION The Inner Balance Coherence Plus™ is a compact Bluetooth-enabled sensor and app system d…
- Measuring Coherence: How the Scoring Works – HeartMath Help – Coherence measurement data accumulation explained.
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- Magnets in Cell Phones and Smart Watches May Affect … – Consumer electronic devices with high magnetic fields such as cell phones and smart watches may affe…
- Magnetic Interference on Cardiac Implantable Electronic … – Background Magnet wireless charging is being utilized increasingly in current generation smartphones…
- Are Bluetooth Headphones Safe with a Pacemaker? | Ng Earsafe – Are Bluetooth headphones safe for pacemaker users? Discover facts, risks, and safety tips in this mu…
- Medical Safety: Which Sleep Wearables are Safe for Heart Devices? – Can I use a sleep tracker with a pacemaker? Learn which sleep wearables are safe for heart devices a…
- Electromagnetic Interference and Implanted Cardiac Devices – PMC – Electromagnetic interference produced by medical equipment can interact with implanted cardiac devic…
- Protecting Your Pacemaker From Smartphones, Power Lines – Smartphones and power lines can interfere with pacemakers and implanted defibrillators. However, whi…
- Electromagnetic Interference in Cardiac Implantable Electronic Devices: Is the Use of Smartphones Safe?
- Potential Cell Phone Interference with Pacemakers and … – Based on current research, cell phones do not seem to pose a significant health problem for pacemake…
- CIED Are Contemporary Smartwatches and Mobile Phones Safe for …
- Pacemakers and Electromagnetic Interference – Let us address any concerns by reviewing the facts and precautions to take when using common electro…
- Radio Frequency Transmission
- Using household appliances and tools – Boston Scientific – While portable MP3 players should not interfere with your pacemaker, the headphones or earbuds shoul…
- HeartMath® Inner Balance™ Trainer Coherence Scoring System
- A review on wearable photoplethysmography sensors and their … – Magnetic ear clips and headphones have been used in the past to obtain PPG signals. Poh et al., prop…
- HRV and Coherence Scores: Understanding the Science – The coherence scores are based on how symmetrical the wave-like HRV pattern is.
- Autonomic responses to single- and dual-chamber pacing – PubMed – We investigated the autonomic effects of short-term, single- and dual-chamber pacing by evaluating f…
- Activity-responsive pacing produces long-term heart rate variability – Rate-responsive pacing reproduces long-term, but not short-term, measures of HRV, suggesting that th…
- Impact of chronic DDD pacing on time-domain indexes of heart rate variability in patients with hypertrophic obstructive cardiomyopathy – PubMed – The aim of this study was to examine whether DDD pacing affects time-domain indexes of heart rate va…
- P.2. Syncope, Pacemaker, CRT & ICD: P.2.8 Effects of Atrial Synchronous Ventricular (VDD) Pacing on Heart Rate Variability In Complete Atrioventricular Block – Abstract. It is known that sympathetic nervous cardiac control is enhanced in the setting of complet…
- Pacemakers and the Freeze-Framer – HeartMath Store
- heart rate variability analysis from 24-hour Holter recordings – PubMed – Aim: Aim of this retrospective study was to analyze the effect of closed-loop stimulation (CLS) and …
- Heart rate and blood pressure variability in patients … – Rate-responsive pacemakers (PMs) aim at having pacing rates as similar to physiological cardiac rhyt…
- Using HRV, Resting Heart Rate, and Training Zones With a … – Heart rate tracking and HRV monitoring have become common tools for guiding recovery and training. B…
- HeartMath Health FAQ – Safety: Sensors are completely safe with no risk of shock. The Bluetooth version uses Low Energy (BT…
- Extraction of Heart Rate Variability from Smartphone … – PMC – NIH – In this paper, we demonstrate that HRV can also be extracted from photoplethysmograms (PPG) obtained…
- HeartMath – App Store – Apple – KEY FEATURES • Real-time HRV Coherence Measurement: Use your phone’s camera or upgrade to the pro se…