6 Modern Cardiac Technologies for Heart Monitoring
In today’s fast-evolving healthcare landscape, monitoring heart health has become more advanced—and more accessible—than ever before. From gold-standard electrocardiography (ECG) to emerging heart monitoring technologies like PPG, ICG, and SCG, a growing number of tools are helping clinicians, health tech developers, and even patients better understand the heart’s activity. In this article, we’ll explore six key heart monitoring methods and highlight how each technology is shaping the future of cardiac care, including commercial examples utilizing these technologies.
6 Heart Monitoring Technologies:
1. Electrocardiography (ECG): The Gold Standard of Heart Monitoring
2. Photoplethysmography (PPG): Non-Invasive and Convenient
3. Ballistocardiography (BCG): Contactless Heart Monitoring
4. Impedance Cardiography (ICG): Beyond Heart Rate
5. Seismocardiography (SCG): Capturing Heart Vibrations
6. Acoustic Cardiography: Listening to the Heart
1. Electrocardiography (ECG): The Gold Standard of Heart Monitoring
OPERATING PRINCIPLE
ECG sensors measure the heart’s electrical activity directly. Electrodes are placed on the skin, and they detect the electrical signals produced by the heart as it beats. These signals are then used to produce an electrocardiogram (ECG), which shows the timing and strength of the heart’s electrical activity.
An electrocardiograph produces an ECG lead by measuring the difference in electrical potential between two points. In the simplest types of leads, these points are represented by two electrodes (as shown in the figure). One electrode acts as the active, or positive, electrode, while the other serves as a reference point. Picture source: www.ecgwaves.com ²
KEY APPLICATIONS
This method is widely used in clinical devices (like Holter monitors, 12-lead ECG machines) and newer wearable devices, in both medical and consumer devices, such as wearable ECG monitors, smart patches and even some smartwatches.
BENEFITS
ECG remains the most accurate method for diagnosing arrhythmias, ischemic events, and other heart conditions.
DIFFERENTIATION FACTOR
ECG is the gold standard because of its accuracy in diagnosing detailed electrical activity, which is crucial for detecting serious conditions like atrial fibrillation (AFib) and ventricular arrhythmias.
COMMERCIAL EXAMPLE: CardioRTHM
CardioRTHM is a wearable ECG monitor for remote heart monitoring. The wireless CardioRTHM solution helps capture hard-to-find arrhythmias by recording and storing high-quality ECG and heart rate data. The device is designed for consumers and healthcare providers who need short term, real-time, on-the-go heart monitoring. CardioRHTM enables easy sharing of ECG measurement data with doctors and medical analysis software or systems.
2. Photoplethysmography (PPG): Non-Invasive and Convenient
OPERATING PRINCIPLE
PPG measures changes in blood volume in the microvascular bed of tissue using light. A LED light is shone onto the skin, and a sensor detects how much light is absorbed or reflected by the blood under the skin, allowing heart rate measurement. Since the volume of blood changes with each heartbeat, PPG can provide an indirect measure of heart rate.
Principle of photoplethysmography (PPG) [104]: (a) reflective mode; (b) transmitting mode; (c) example of PPG signal.¹ Picture source: https://www.researchgate.net/figure/Principle-of-photoplethysmography-PPG-104-a-reflective-mode-b-transmitting_fig7_338723696¹
KEY APPLICATIONS
PPG is widely used in consumer devices such as fitness trackers and smartwatches (like Apple Watch, Fitbit), PPG is typically used to monitor heart rate and other cardiovascular metrics.
BENEFITS
Non-invasive, inexpensive, and easy to integrate into wearable devices. However, it’s less accurate than ECG for detecting detailed cardiac events like arrhythmias, as it measures heart rate rather than electrical activity, but lacks the precision for detecting complex cardiac issues.
DIFFERENTIATION FACTOR
PPG is a scalable and user-friendly technology that enables widespread heart rate monitoring. Its ability to be integrated into wearables offers an accessible entry point for heart health monitoring in a consumer context.
COMMERCIAL EXAMPLE: Apple Watch (Series 6 and later)
Apple Watch uses PPG to monitor heart rate and alert users to irregular rhythms. Though less precise than ECG, it has brought heart monitoring to the masses, serving as an important tool for preliminary health tracking. The target group of Apple Watch is health-conscious consumers and individuals looking for basic cardiac monitoring.
3. Ballistocardiography (BCG): Contactless Heart Monitoring
OPERATING PRINCIPLE
BCG measures the mechanical forces generated by the heart as it pumps blood, which causes small movements throughout the body. Sensors detect these micro-movements to estimate heart activity.
Schematic diagram of BCG and ECG synchronous acquisition system.³ Picture source: Heart rate detection method based on Ballistocardiogram signal of wearable device: Algorithm development and validation. Geng, Duyan et al. Heliyon, Volume 10, Issue 5, e27369³
KEY APPLICATIONS
BCG is used for non-contact heart monitoring, commonly integrated into smart beds or sleep monitors. It’s not as widely used in wearables but can be found in specific medical applications.
BENEFITS
Allows for heart monitoring without attaching sensors directly to the body, but it’s less precise than ECG and not typically used for diagnosing complex cardiac issues.
DIFFERENTIATION FACTOR
BCG offers the possibility of passive, non-intrusive monitoring, which is key for long-term cardiac data collection without patient discomfort.
COMMERCIAL EXAMPLE: Emfit QS Sleep Tracker
Emfit QS is a non-contact sleep tracker that monitors heart rate, breathing, and sleep quality using BCG technology. It’s placed under the mattress, offering continuous monitoring without the need for wearables. The device is designed for athletes, sleep specialists, and researchers focused on long-term, non-invasive health tracking.
4. Impedance Cardiography (ICG): Beyond Heart Rate
OPERATING PRINCIPLE
ICG measures changes in electrical impedance across the chest during the cardiac cycle. As the heart beats and blood volume changes, the electrical impedance (resistance to electrical flow) varies. By tracking these changes, ICG can estimate cardiac output and other cardiovascular parameters.
KEY APPLICATIONS
ICG is used for advanced cardiovascular monitoring, particularly in clinical settings, where it provides real-time insights into heart performance, especially over time. ICG can sometimes be found in wearable form.
BENEFITS
Provides insight into cardiac function (e.g., stroke volume, cardiac output) in addition to heart rate.
DIFFERENTIATION FACTOR
ICG offers a deeper look into cardiac function beyond basic heart rate, providing critical data on the heart’s efficiency, which is invaluable for managing patients with heart failure or monitoring surgical outcomes.
COMMERCIAL EXAMPLE: PhysioFlow
PhysioFlow is a non-invasive device used to measure cardiac output and other hemodynamic parameters using ICG technology. It provides real-time feedback on cardiac function and is often used for continuous monitoring in hospitals, in critical care and cardiovascular research settings.
5. Seismocardiography (SCG): Capturing Heart Vibrations
OPERATING PRINCIPLE
SCG detects the tiny vibrations produced by the heart as it contracts and pumps blood. Accelerometers placed on the chest capture these vibrations, providing mechanical insights into heart function. The data can be used to evaluate heart function and identify specific cardiac events.
KEY APPLICATIONS
SCG is used for heart function monitoring, often combined with ECG to give a more comprehensive view of cardiac performance. Found in some wearable devices and medical applications for monitoring heart function.
BENEFITS
Like BCG, SCG is non-invasive and captures mechanical aspects of heart function. However, it’s less commonly used and still being researched for broader applications.
DIFFERENTIATION FACTOR
By combining mechanical and electrical data, SCG can provide a fuller picture of heart health, especially in early detection of heart diseases.
COMMERCIAL EXAMPLE: MyoVista by HeartSciences
MyoVista integrates SCG with ECG to provide both mechanical and electrical insights into heart health. It helps in the early detection of heart dysfunction. It is designed for cardiologists and clinical researchers focused on preventive care and early diagnosis of heart conditions.
6. Acoustic Cardiography: Listening to the Heart
OPERATING PRINCIPLE
This method uses microphones or accelerometers to detect heart sounds (similar to a stethoscope) and heart mechanical movements. The captured heart sounds (such as the lub-dub) provide insights into heart valve function and the timing of cardiac events.
KEY APPLICATIONS
It’s primarily used in clinical settings to diagnose heart failure and valve-related issues or experimental settings rather than mainstream wearables. Some devices combine acoustic sensors with ECG for enhanced cardiac monitoring.
BENEFITS
Useful for assessing heart valve function and timing but not as detailed for detecting electrical problems like arrhythmias.
DIFFERENTIATION FACTOR
The addition of heart sound analysis allows for detailed assessments of valve function, making it highly useful for diagnosing and managing heart failure
COMMERCIAL EXAMPLE: AUDICOR
AUDICOR combines ECG with heart sound monitoring to deliver detailed information on heart valve function and mechanical timing. It’s often used for patients with heart failure to track cardiac performance. The device is intended for heart failure specialists and cardiologists in clinical settings.
Conclusions of the Modern Heart Monitoring Technologies
For med tech and other professionals working on healthcare industry, understanding the various methods of heart monitoring is crucial for developing and selecting the right technology for different applications. While ECG remains the gold standard, other heart monitoring technologies using PPG, ICG, and SCG offer unique insights and benefits, depending on the use case.
As the healthcare landscape shifts towards wearable and non-invasive monitoring, integrating these technologies into innovative devices will enhance patient care and open new possibilities for continuous, remote cardiac monitoring. From consumer wearables to advanced clinical tools, each method contributes to a more comprehensive understanding of heart health, offering tailored solutions for a diverse range of patients.
References
- Picture source: Dzedzickis, Andrius & Kaklauskas, Arturas & Bučinskas, Vytautas. (2020). Human Emotion Recognition: Review of Sensors and Methods. Sensors. 20. 592. 10.3390/s20030592. https://www.researchgate.net/figure/Principle-of-photoplethysmography-PPG-104-a-reflective-mode-b-transmitting_fig7_338723696
- ECG and ECHO Learning. Clinical ECG Interpretation, Section 1, Chapter 3. https://ecgwaves.com/topic/ekg-ecg-leads-electrodes-systems-limb-chest-precordial/
- Heart rate detection method based on Ballistocardiogram signal of wearable device: Algorithm development and validation. Geng, Duyan et al. Heliyon, Volume 10, Issue 5, e27369 . https://www.cell.com/heliyon/fulltext/S2405-8440%2824%2903400-5#fig1
What is Movesense?
Movesense is a Finnish MedTech company, partner and a manufacturer providing accurate data for measuring or monitoring ECG, HR and HRV with customizing opportunities and reliable Finnish manufacturing with flexible and scalable quantities.
What is Movesense MD?
Movesense MD sensor is our flagship product, a wearable and wireless medical ECG, HR and HRV sensor for med tech and wellbeing companies, hospitals and health care operators and research. CardioRTHM is a wearable ECG monitor for remote heart monitoring, based on Movesense’s medical technology.
