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ECG Services |

Fysiologic ECG Services is specialized in the analysis and registration of electrocardiograms (ECGs). Our analysis procedure guarantees high reliability. Our ECG services deliver tailor-made solutions from analysis to report.

Analysis |

Our analysis algorithm guarantees continuity, speed and analyses of the highest quality. Our analysis software packages are state-of-the-art: we can analyse data from each and every ECG recorder on the market. Also remotely at patients' homes (Holter-at-Home service).

Knowledge centre |

Fysiologic organizes accredited retraining courses and continuing education on anatomy, rhythm and conduction disorders and ECG analysis and interpretation.

Leads Online |

LEADS Online provides you with the opportunity to extract several vectorcardiographic variables (the ventricular gradient and the spatial QRS-T angle in particular) from the standard 12-lead ECG, for scientific purposes.

Global |

Fysiologic Global operates worldwide. Next to our headquarters in Amsterdam, we have branches in Denmark, South-Africa and the Netherlands Antilles.

Our DNA |

In the Netherlands, each day more than a hundred people die of cardiovascular disorders. Therefore, we spend each minute of our time on electrocardiography: we register, analyze, diagnose, improve and innovate. By doing this, we have been saving lives since 1977. Because ECG is in our DNA.

The patient |

Your doctor has requested an ECG registration to monitor your heart rhythm. Here we provide you with more information on ECG in general and on using the ECG recorder.

Material |

Would you like to return a recorder for repair? Download here the RMA form.     Order your ECG disposables quick and easy with this online order form:

Contact |

Privacy statement Read our privacy statement  

Are you
a patient?

Fysiologic offers full support

Fysiologic has experience working with various types of analysis software. We can analyse data from any ECG recorder, holter or software platform.


You can contact us anytime for questions or special requests. Our team provides an extensive instruction and installation of the ECG recorders and software on any chosen location. Staff members of Fysiologic ECG Services can be reached by phone 24/7.


We offer an all-in-one solution. You will only be charged a fixed amount per analysed ECG. We organise all logistics around the ECG installation at your patients home free of charge.

Fysiologic offers full support



Fysiologic has experience working with various types of analysis software. We can analyse data from any ECG recorder, holter or software platform.


You can contact us anytime for questions or special requests. Our team provides an extensive instruction and installation of the ECG recorders and software on any chosen location. Staff members of Fysiologic ECG Services can be reached by phone 24/7.

All-in-one solution

We offer an all-in-one solution. You will only be charged a fixed amount per analysed ECG. We organise all logistics around the ECG installation at your patients home free of charge.


We deliver digital reports of maximum quality; fast and always within the desired timeframe, without sacrificing the reliability of the reports. In urgent situations, we send you the results within 30 minutes.

Read more…

ECG Analysis

Fysiologic ECG Services is specialized in the analysis and registration of electrocardiograms (ECGs). We analyze your 12-lead, Holter (24, 48 and 72 hour) and Event registrations within any desired timeframe.

Read more…


The analysis of ECGs can not be done solely by a machine. Therefore our team consists of ECG analysts and cardiologists with ample years of experience. Each analysis is checked and interpreted by two separate analysts, supervised by a cardiologist. This procedure guarantees a high reliability.

Read more…

Fast and reliable

Our everyday goal is to inform you as soon as possible about potential rhythm or conduction disorders of your patient. The high quality of our analyses ensures that you will never have to doubt the reliability of the report, or that you should feel the need to check the analyses in detail yourself.  Safety, speed, and reliability are our first priority.


With regard to the privacy of your patient, the recorded ECG data is transmitted to our analysis center through a secure internet connection. A report will be returned to you within the desired timeframe, again through a secure internet connection. Our well-trained team and our strict analysis procedures guarantee the reliability and quality of our reports. In urgent situations, we can forward the results very fast, often within 30 minutes.


For example reports, click here.

ECG diagnostic knowledge center

Fysiologic ECG Services has entirely specialized in ECG diagnostics. We started in 1977 with the registration and analysis of electrocardiograms (ECG) for general practitioners, cardiac specialists, and hospitals. Since then we have analyzed more than two million ECG analyses. And that number is still growing. In the more than 40 years since our business started, we have acquired a lot of knowledge and experience. Our love for the ECG inspires us to keep on gathering knowledge, to innovate and to introduce new diagnostics.


We provide you with analyses of 12-lead ECGs, Holter ECGs (24, 48 and 72 hours) and Event ECGs. For specifications of the reports, click here:


Specifications Holter Reports
  • Continuous 24/48/72 hour registration (2 to 12 lead).
  • Selection of relevant ECG-strips.
  • Quantification of supraventricular and ventricular arrhythmias.
  • Reports including frequency trendgram, frequency histogram, RR intervals and bar graphs of arrhythmias.
  • Customized reports possible, for example a complete analysis of other cardiological aspects, including QT interval, ST/T abnormalities, PR interval, Heart Rate Variability (HRV) and Heart Rate Turbulence (HRT).
Specifications Event Reports
  • 7 or 14 days continuous recording (2 lead).
  • Patient reporting Event markers (by using the Event Button).
  • Possibility of detecting and reporting asymptomatic rhythm and conduction disturbances, due to continuous recording.
  • Customized reports possible.

Computer-assisted analysis

Our analysis software is state-of-the-art and extremely trustworthy. But in the end, the analysis of ECGs can not be done solely by a machine. Therefore our team consists of ECG analysts and cardiologists with ample years of experience and extensive knowledge of electrocardiography. To guarantee the high quality of our reports our team follows a strict procedure:


  • The ECG and the events file of the patient are uploaded through a secured connection and sent to the Fysiologic analysis centre.
  • Our trained people in the data entry department check the data and enter it in our analysis program. All ECG analysts have a medical background and have completed our internal training, including an entry and exit test.
  • Our in-house developed algorithm detects the RR interval and classifies possible rhythm or conduction disorders.
  • The results of this process are verified and validated by the analyst. He or she adds an analysis of the – to the physician -most relevant rhythm strips.
  • After this report is validated by a highly experienced ECG-supervisor, the final report is generated.
  • The entire procedure is supervised by our cardiologist. He is available at all times for questions or for discussing complicated cases.


This extensive procedure guarantees reports of high quality and reliability.


Customised solutions

Customised solutions

Fysiologic ECG Services offers customized solutions from the start until the end of the process, an all-in-service and an experienced team that deals exclusively with ECG analyses. Our way of working guarantees continuity, reliability, speed and the highest quality.


Our state-of-the-art analysis program enables us to analyse ECG data from other suppliers. Also remotely at patients’ homes (Holter-at-Home service). The reports will be coupled in a safe way with the national electronic patient files and are easily retrievable.


You can outsource the entire process to us with confidence. Because in the end only one thing counts: the most optimal treatment for your patient.

The algorithm

The heart of the analysis

The ECG analysis process is based on a specifically developed algorithm. The ECG analysis program compares the different individual QRS complexes (heart beats). Rhythm and conduction disorders are defined after manual classification, on the basis of the length of the intervals between QRS complexes.

The algorithm and the supporting software are constantly updated, following the latest medical and technological developments.


Fysiologic ensures continuity in diagnostics

The Fysiologic Holter-at-Home service enables you as a healthcare professional to monitor a patient at home

  • Holter ECGs (24-, 48- and 72-hours) and Event ECGs
  • Rapid diagnosis for the patient
  • Continuity of your care
  • Trusted quality of Fysiologic.

For more information click here.

App Fysiologic Journal

App Fysiologic Journal

While using the ECG Recorder, the patient has to keep a journal of his or her symptoms and activities. Normally this journal is kept on paper. However, today’s digital society asks for something more easy to use. Therefore, we developed the App Fysiologic Journal, available for each patient mid-2020.

In the App the patient only has to select relevant activities or symptoms. The App will store these at the right date and time. Later, during the ECG analysis, these data will be linked to possible rhythm or conduction disorders.


For a manual, click here.

ECG Access Online

ECG Access Online

ECG Access Online is a user-friendly program that can be installed locally on your computer. ECG Access Online is used to program the ECG Recorder before giving it to the patient. It allows to enter information like name, birth date and BSN or patient identification number, as well as the duration of the registration and the desired number of leads.

When you want to learn more

Fysiologic organizes retraining courses and continuing education on anatomy, rhythm and conduction disorders, and on ECG analysis and interpretation. Courses are taught by a highly motivated and experienced instructor. 


The courses are suitable for anyone working with or responsible for cardiac patients. After attendance of the course of their choice, participants receive a signed certificate. Supervisor is dr. P.J.P. Kuijer, cardiologist and teacher at the Radboudumc Nijmegen.


Do you want to know more?

Heart and blood circulation

1 day course

Everything about the heart: from the structure at cell level to normal functioning in the body. We will show you all cardiac structures and explain how they work. During an anatomical dissection class you can find these structures yourself when dissecting a pig’s heart. Accredited 6 points.

Do you want to know more?

Rhythm disorders part 1 (tachycardia)

1-day course

This course centers on tachycardia, heart rhythm disorders in which the heart beats too fast. We will focus on frequently occurring disorders, like extrasystoles and atrial fibrillation. You will learn to recognize these rhythm disorders and to differentiate between innocent and life-threatening disorders. Accredited 6 points.

Do you want to know more?

Rhythm disorders part 2 (bradycardia)

1-day course
This course centers on bradycardia, heart rhythm disorders in which the heart beats too slow. We will focus on disorders with very slow rhythms and disorders in which the heart stops for a couple of seconds. You will learn to recognize these rhythm disorders and to differentiate between innocent and life-threatening disorders. Accredited 6 points.

Do you want to know more?

Interpretation of the resting ECG

2-day course
In this course, you will learn how an ECG is made and why this knowledge can be of use for you in your daily practice. You will be trained how to differentiate quickly between innocent and life-threatening ECG registrations, and will learn about the possibilities and limitations of ECG interpretation. Accredited 9 points.

Do you want to know more?

Rhythm disorders

2-day course
The first day of this course discusses tachycardia, disorders in which the heart beats too fast. The second day focusses on bradycardia, disorders that make the heart beat too slow. Furthermore, you will learn about the ECG roadmap, ECG characteristics, clinical implications, and the indications for Holter-ECG en Event-ECG. Accredited 9 points.

Do you want to know more?
In three steps… Scientific backgroundOne credit per ECG What is LEADS online?

Fysiologic LEADS Online

Specific vectorcardiographic variables, the ventricular gradient and the spatial QRS-T angle in particular, have proven to be quite valuable in risk and prognosis analyses of different clinical syndromes. These variables can not be computed with the standard ECG equipment. The LEADS program computes a vectorcardiogram (VCG) from the standard 12-lead ECG and extracts several vectorcardiographic variables for scientific purposes. By LEADS Online the LEADS program is made available online.

What is LEADS online?

Back to intro

LEADS1 Online provides you with the opportunity to perform online an additional analysis of a standard 12-lead electrocardiogram (ECG). LEADS computes a vectorcardiogram (VCG) from the 12-lead ECG. A VCG is a 3D-representation of the electrical heart activity. It partially contains other information than variables that can be extracted from the standard 12-lead ECG. Especially, the ventricular gradient and the spatial QRS-T angle turned out to be quite valuable in risk and prognosis analyses of different clinical syndromes. The LEADS program extracts tens of VCG variables from each electrocardiographic recording, and tens of ECG variables as well. Thus Leads Online facilitates the user in answering specific scientific questions.


1: Draisma et al, 2005; for further references see www.leadsonlineecg.nl.

Scientific background

Back to intro

The core of LEADS Online is an existing computer program: LEADS. LEADS has been developed about 10 years ago by a team of specialists that still maintain and improve the program, making it highly trustworthy. Since the very beginning, the development team consists of Cees A. Swenne, PhD2 (concept, algorithms, testing), Harmen H. Draisma, PhD3 (algorithms, realization) en Arie C. Maan, PhD4 (realization and testing). Some time later, Sumche Man5 (realization, testing) joined the group.


LEADS analyses are widely used for research activities, which has led to more than 35 scientific publications (mostly concerning the ventricular gradient and the spatial QRS-T angle6). LEADS Online provides access to the practical results of over 10 years of scientific research in this domain. The analyses and computations of the LEADS program are actively supported by specialists in the field, affiliated with the Leiden University Medical Center (LUMC, Leiden).

2: http://swenne.net/c.a/publications.htm; 3: https://nl.linkedin.com/in/harmendraisma; 4: https://www.researchgate.net/profile/Arie_Maan/publications; 5: https://nl.linkedin.com/pub/sum-che-man/16/81a/a2; 6: for references see website www.leadsonlineecg.nl.

In three steps…

Back to intro

…you can perform a VCG analysis and compute the ventricular gradient,
the spatial QRS-T angle, and many other variables:


1:     upload an ECG

2:     let LEADS compute the VCG variables

3.     download the results.


All computed VCG (and ECG) variables are pooled in a comma-separated-values (.csv) file, that can directly be imported for further processing in a spreadsheet or statistics program like Excel of SPSS.
Additionally, you receive, per ECG analysis, a number of graphical results: a conventional ECG representation, a Cabrera representation of the average beat with the values of the most important VCG variables, and a vectorcardiogram.

One credit per ECG

Back to intro

Prior to uploading, you buy credits. Credits are available in bundles of various sizes. When you upload your ECGs, they are automatically added to the LEADS Online analysis queue. Each uploaded ECG uses up one credit. In case you upload more ECGs than you have credits remaining, the surplus of ECGs stays on the server. As soon as you buy additional credits, the ‘on hold’ ECGs will be scheduled to be analyzed. In case you decide that the remaining ECGs should not be analyzed at all, you can delete them from the server prior to buying new credits.

Around the globe

Fysiologic Global operates worldwide. Fysiologic Global offers ECG Services in several countries on three different continents. We have branches in South-Africa, Denmark and the Netherlands Antilles.


On the left, you will find the countries in which we operate and the contact details of our local agents.



  • Denmark


  • Sweden


  • Kenya


  • Office South Africa
  • 20 Mynie Road, Wetton, Cape Town, South-Africa


  • Colombia


  • Suriname


  • Curaçao

Sint Maarten

  • Sint Maarten


  • Bonaire

St. Eustatius

  • Sint Eustatius, Caribisch Nederland

United Kingdom

  • Verenigd Koninkrijk



Each day more than a hundred people die from cardiovascular disorders. At the moment the Netherlands have 1 million cardiovascular patients (www.hartstichting.nl). Through population ageing and diseases like diabetes, lung diseases and obesity, that amount will increase even more. As specialists in registration and analysis of ECG’s, we at Fysiologic ECG Services devote all our knowledge and expertise to identify heart problems at early stages.

How it started…
For whom?
Knowledge exchange
Work in progress

We are constantly busy improving the quality of our ECG analyses. Through our service and the reliability of our reports we relieve the burden of doctors. The more convenient it is for the doctor, the more time he or she can spend on the patient. That is our ultimate goal: improving the health of the person behind the ECG.

Fysiologic ECG Services was founded in 1977 by John den Engelsman in cooperation with the Cardiology Department of the Utrecht Academic Hospital. From the start, Fysiologic was mainly concerned with ECG analysis. In 2007 Robert den Engelsman succeeded his father as CEO and took over the company. In the last ten years the company is growing steadily. In 2009 Fysiologic entered the international market. It cooperates with several different hospitals, clinics and doctor’s practices.

Everyone using ECG for diagnostics can consult us. Our services are purchased by academic and peripheral hospitals, diagnostic labs and doctor’s practices. Among others, we collaborate with the Amsterdam Medical Centre,  VU Medical Centre, University Medical Centre Utrecht and the St. Antonius Hospital in Nieuwegein.

We are working with sensitive patient information. Information security is therefore very important to us. Fysiologic ECG Services is ISO 27001 certified and NEN 7510 accredited. We are one of the first in our field to invest in ISO 27001 certificates.


View our certificates on VerifEye >

Fysiologic ECG services provides practical support in knowledge and resources for multiple scientific studies. We are co-author on various publications. We allow medical students to do internships with us and PhD students to carry out research at our company. They learn a lot of our cardiologist, experienced ECG analysts and ECG supervisors.


Furthermore, we keep up with the relevant literature and visit conferences in our area of expertise. By sharing our knowledge and expertise in this way, we both contribute to relevant medical and scientific developments and at the same time maintain our own level of knowledge.

We at Fysiologic are always trying to improve: streamlining our processes and enhancing the quality of our products. Thereby, patient safety and user-friendliness are the central issues.


We are currently developing a digital journal that makes it easier for the patient to keep track of his or her activities and symptoms. This App Fysiologic Journal will be launched mid-2020.


In this way we are always continuing to innovate to make our products, processes and services better, faster and easier. Both for you as our client, as well as for your patient.

What is an ECG Recorder?What do you see on an ECG?The application and usage of the ECG RecorderA bit inseccure?More questionsJournalHow does the heart work?What are heart rythym disorders?

The patient

What is an ECG Recorder?

An ECG Recorder is a wearable medical device that registers your heart rhythm during a determined period of time (days or weeks).  Such a registration we call an electrocardiogram (ECG). Your doctor has requested this medical examination, because it provides important information about the functioning of your heart.

What are heart rhythm disorders?

A heart rhythm disorders is a recurring deviation of the normal heart rhythm. With each heartbeat an electrical pulse causes the heart to contract. In a normal heart rhythm this contraction occurs at a regular pace. When something is wrong with the production or the conduction of the electrical pulse, the heart rhythm changes. The heart starts to beat to fast or to slow. Or the pace becomes irregular.


Untreated arrhythmias in the long run can impair the pump function of the heart or lead to heart failure. Mostly these arrhythmias are quite innocent or easy to treat. Which treatment the doctor will prescribe, is dependent on factors like the age of the patient, the origin and the severity of the disorder.

How does the heart work?

The heart is a large muscle consisting of four hollow spaces. The upper two cavities are called the atria, the bottom two the chambers. Because of the regular contraction of atria and chambers the blood is pumped trough the body, providing the muscles and organs with oxygen and nutrition.


The heart consists of heart muscle cells. When these cells are stimulated electrically, the heart contracts. The electrical stimulus starts in the sinus node (that regulates the heart rhythm), and spreads through a conduction system first to the atria and second to the chambers, causing them to contract in succession.

What do you see on an ECG?

Heart muscle cells are electrically charged. As a result the heart as a whole generates an electrical field. The ECG is a graphical depiction of the changes in the heart electrical field during the contraction and relaxation of the heart. As the electrical impulse spreads through the heart by way of a conduction system, the strength and the direction of the heart electrical field are constantly changing.


In each part of the heart a different kind of signal is generated. These signals together form the ECG signal. By looking at the shape of the ECG, you are not only able to see deviations in the heart rhythm, but you can also determine where in the heart the problems originate.

The application and usage of the ECG Recorder

Your doctor or assistant will apply the skin electrodes to your chest. These are connected by cables to the ECG Recorder. While you are wearing the ECG Recorder, you will keep a patient journal in which you list your activities and eventual symptoms.


The recorder is not waterproof. During the registration you can not take a shower or a bath, or go swimming. Washing with a washing glove is allowed. When you need to wear the recorder for a longer period of time, we will provide you with a couple of sets of skin electrodes and an instruction how to apply them again after bathing.


In the journal you receive with the ECG Recorder, you will note your activities, together with the date and time that you undertook them. For example, you list walking, cycling and doing sports, but also sleeping, watching tv and eating. You will also note your symptoms, like heart palpitations, thightness, vertigo and pain in the chest.


Click here for the PDF.

A bit insecure?

For the reliability of the investigation it is very important that you understand everything and carefully follow the instructions. Therefore, do not hesitate to contact your doctor, general practitioner or assistant when you have questions. Especially when you think you did not understand of forgot an instruction. Some people like to bring a family member or friend to the application of the ECG Recorder, so this person is able to help you with reattaching  the electrodes.

More questions


Download the Teamviewer program here and we can support you directly and remotely:



Temporarily in need of extra people? We offer skilled personnel to strengthen your team and serve your patients at your location.
We take a lot of work off your hands, which leads to a quicker diagnosis of your patients and to more space in your occupancy rate and a reduction of the workload.


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