Survival prospects of heart attack patients by mobile measurement of cardiovascular risk factors


  • Polyclinic rechts der Isar Munich, Internal Medicine I, Prof. Dr. Georg Schmidt
  • INVADE Institute for Health Services Research


Ensuring regular and frequent risk assessment of cardiac patients so that changes in their health status are recognized right away and patients get treatment before their health is worsening significantly.


Replacing the current method of assessing the cardiac risk, namely the need for a 30 min measurement of ECG, blood pressure and respiration rate in the doctor´s office by a simple over-night measurement at home. Thus, enabling a regular assessment of current risk level of cardiac patients at home.

What made the customer use a cosinuss° solution:

cosinuss° provides a wearable sensor that collects PPG signal with medical accuracy, enabling the calculation of a precise Polyscore (= cardiac risk score) as well as heart rate, respiration rate, heart rate variability and oxygen saturation of the blood. The in-ear sensor at the same time is easy to use, convenient and can be worn during night.

Test procedure:

Type of studyPilot study
Used devicescosinuss Two°
cosinuss° LabClient
cosinuss° Server
ReferencePulse oximeter with fingerclip
Timeframe6 weeks
Location of measurement
  • A doctor´s office near Munich, Germany
  • Individual patients’ homes
Number of test persons30
Test person statisticsAge: 60-74 years
Gender: male and female (no concrete figures)
Rec. health issues: Cardiac patients
  1. 30 min measurement in rest in the practice
  2. 5-6 hours of overnight measurement at home
UsabilityHandling of in-ear wearable and gateway device on their own at home.
Collected dataPPG raw signal and signal quality score
Data transmissioncosinuss° Two -> cosinuss° LabClient: Bluetooth
cosinuss° LabClient -> cosinuss° Server: Network connection
Data locationcosinuss° Two -> cosinuss° LabClient -> cosinuss° Server
(server location in Nuremberg, Germany)
  1. Measuring patients with cosinuss° Two and fingerclip in doctor´s office.
  2. Patient takes in-ear sensor and LabClient home and sleeps with sensor in the ear. Measuring PPG raw signal from midnight until 6:00 in the morning. Patient brings cosinuss° Two and LabClient back to the doctor.
Object of investigationCorrelation of simultaneously measured photoplethysmographic signals (finger clip and in-ear sensor) related to signal differences from pulse beat to pulse beat (signal amplitude and wavelength)
Secondary endpoints:

  1. Difference in the proportion of artifact-free recording in the total recording time between finger clip and ear clip and between in-ear sensor measurement during daytime at the GP and during the night hours between 0 and 6 o’clock.
  2. Correlation between fingerclip polyscore and in-ear sensor polyscore.
  3. Correlation between earclip polyscore during the day at the doctor and at night between 0 and 6 o’clock
Data analysisData is processed only by Prof. Dr. Schmidt and his team.

Conclusions drawn from collected data:

  • Data analysis not yet completed and pending due to Corona.
  • First estimation of Prof. Dr. Schmidt: Data of cosinuss° Two looks very promising so far

Technical validity:

  • First estimation very positive.
  • Detailed analysis pending due to Corona.

Risks and issues encountered:

  • Fast uploading requires corresponding Internet connection speed in medical practices and at the patient’s home.


  • Positive feedback of MTA/test persons: Smooth data acquisition in the doctor’s office and in-home monitoring including nightly data acquisition while sleeping.
  • User-friendliness and wearing comfort confirmed by study participants aged 60-74 years.
  • Uploading the raw data requires a correspondingly fast Internet connection.

Customer feedback

We assume that the auditory canal is less exposed to sources of interference such as jerky movements than the fingertip, especially in everyday life. Consequently, a measurement of the photoplethysmographic signal in the ear canal would have to provide more stable and artifact-free signals than the measurement at the fingertip.

What´s next?

Prof. Dr. Schmidt and his team are planning to conduct a prospective cohort study with 1.200 participants.

Mögliche Anwendungsgebiete

Telemonitoring, Mobile Gesundheitsanwendungen, Gesundheit zu Hause