At-Home Clinical ECG: Now and After The Pandemic – Interview with Dr. Ruey-Kang Chang, CEO, QT Medical


Many fields of medicine are undergoing a transformation due to the COVID-19 pandemic, as patients are kept away from clinics as much as possible. Patients are now regularly visited by their doctors over video calls, are asked to perform certain procedures on their own, and are prescribed medical devices that would normally be used by clinical staff.

Heart monitoring is the most important component of medical care for millions of people suffering from cardiovascular conditions, particularly those most at risk from COVID-19 complications. But receiving a clinical grade electrocardiogram (ECG) normally involves office visits, putting some of the most vulnerable at risk of exposure to the virus. Consumer devices simply don’t provide the complex signal information that the heart generates that cardiologists require to produce confident diagnoses.

QT Medical, a firm based outside of Los Angeles, California recently made available the PCA 500 system that allows patients themselves to conduct comprehensive ECG exams. The tracings that are produced rival those that are generated by hospital ECG machines, and so can be used just as reliably by cardiologists. Patients can conduct exams on their own at home and the data automatically shared with their doctors for a close review. QT Medical even setup a service called Xpress ECG that provides 12-lead ECG tests physicians can order for their patients to receive in the mail.


We had a chance to speak with Dr. Ruey-Kang Chang, CEO of QT Medical, about the PCA 500 system, its capabilities, and what it can offer cardiologists working during the ongoing pandemic.

Medgadget: QT Medical’s device allows patients to perform 12-lead ECG tracings on their own. What was the motivation behind this goal?

Dr. Ruey-Kang Chang, CEO of QT Medical: What we initially set out to do was to create an ECG system that is pediatric friendly, especially for babies. During the process of development, we found a better way to do a 12-lead ECG test, and reinvented the ECG with PCA 500 for the 21st century. We have two goals for our ECG: to set a new standard on how 12-lead ECG tests are performed, and to democratize 12-lead ECG to all patients who can benefit from personalized heart disease management.

Medgadget: Compare the quality of tracings that a patient can produce using your device versus what a cardiologist can achieve at the hospital.

Dr. Chang: The market is filled with all kinds of single-lead ECG devices for personal use. 

There are also some that claim to be 12-lead, but use fewer electrodes and calculation algorithms to “create” a 12-lead ECG. PCA 500 is a true medical standard 12-lead ECG: not only do the electrode placements follow the AHA guidelines, the electrode sensors and materials are also of hospital quality.

We conducted an “equivalence study” which showed that PCA 500 produced ECGs, read by 3 blinded cardiologists, no different than that of the Philips Pagewriter TC70. One of the comments we often get from cardiologists is that the signal quality from patients’ ECG recordings at home using PCA 500 are often better than ECGs performed by technicians in the hospital.

Here are a few key points that illustrate why our ECG signal quality is better: First, a lot of noises and artifacts come from the cables and leadwires. Our electrode strip has no cable or leadwires. Second, when the chest electrodes are in one piece, they help to stabilize each other and decrease noises from muscles and movements. Third, we did extensive studies to identify noises from a home environment and created proprietary algorithms to remove the noises.

Medgadget: Please describe the workflow when using your device.

Dr. Chang: As said, PCA 500 is a medical grade 12-lead ECG for professional and for personal use. When PCA 500 is used in a physician’s office, it offers several advantages:

  1. Minimal personnel training is required, which also makes staffing easier;
  2. All ECGs are managed centrally in the cloud and digital copies of ECG reports in PDF are EMR compatible;
  3. Single-use pre-positioned electrodes eliminate the cables and leadwires, thus minimizing the risks for COVID transmission, and make disinfection of the ECG machine between patients much easier.

In response to the surge of needs for telehealth and remote patient monitoring in the pandemic, we now offer the Xpress ECG service. Xpress ECG is an on-demand or periodic 12-lead ECG test the physician orders for his or her patients. First, the physician sets up an online dashboard account with QT Cloud at no cost. From the dashboard, the physician can order Xpress ECG tests and manage all the ECG studies and reports. When the physician’s office orders an Xpress ECG test for a patient, QT Medical receives the order and ships out an Xpress ECG kit, which includes a PCA 500 recorder, an electrode strip, printed instructions, and a postage-paid return envelope. When the patient completes the ECG test, the physician will receive a notification via email with a link to the dashboard. On the dashboard, the physician can review the ECG results, finalize the report, and make management decisions.

Medgadget: How and for whom is it prescribed? What are the use cases?

Dr. Chang: PCA 500 is a medical standard 12-lead ECG that can be used in conventional healthcare settings such as clinics, urgent care centers, and nursing homes. There are many other places where a 12-lead ECG is needed, but often there is no trained personnel to perform the test, such as airlines, cargo ships, mining sites, oil rigs, remote locations, jails and prisons, schools and clinical trials. PCA 500 can fill the gap. 

There are many patients who benefit from using PCA 500 at home, but the cost may be prohibitive and insurance may not cover the purchase. To make PCA 500 accessible and affordable to patients, we believe Xpress ECG is the right solution. Xpress ECG is also the right 12-lead ECG solution for physicians who are starting or expanding their telehealth practice. For patients seen in virtual visits who need an ECG test, Xpress ECG delivers high quality 12-lead ECG tests in just a few days. Xpress ECG can be an alternative to ECG tests done in physician’s offices as well. Using Xpress ECG to get ECG tests done at a patient’s home instead of in the office will enhance workflow in clinic visits, reduce the risks for infection, and lower the cost.

Medgadget: How has the COVID-19 pandemic affected cardiac care of patients, and what is your technology’s role to address this now and in the post-pandemic future?

Dr. Chang: PCA 500 electrodes offer a new way of performing a 12-lead ECG test—the electrode placements will be fast, accurate, consistent and standardized. In addition to reducing variations, errors and personnel cost, the single-use PCA 500 electrodes with no cables greatly lower the risks for coronavirus transmission and the time spent on dis-infecting the equipment. We hope PCA 500 is not only an alternative to conventional ECGs in the pandemic, but it will become the standard for all 12-lead ECG testing in the future.

Patients with heart disease are at much higher risks for COVID-related morbidity and mortality. It has been a challenge to many physicians to continue providing quality care while minimizing the risks of exposure to potential infection. Xpress ECG offers the solution to telecardiology visits and the increasing needs for remote patient monitoring. The need for a 12-lead ECG solution will go beyond the pandemic, as the importance and needs for telehealth, home care and monitoring continue to rise.

Medgadget: Do you foresee that an app may one day be able to automatically review ECG tracings and provide analyses beyond spotting cardiac arrhythmias?

Dr. Chang: Excellent question! We currently provide preliminary ECG interpretation by computer algorithms which are cloud based. Once an ECG is done, the signals are sent to the user’s cloud account, and our cloud algorithms process the signals, filter out the noises, then measure and analyze the ECG patterns. The current algorithms can detect arrhythmias, such as afib, SVT, and structural findings, such as hypertrophy or ST segment elevation. We are now working on machine learning algorithms to make more accurate and extensive ECG analysis and interpretation. I believe a comprehensive 12-lead ECG assessment will not only be diagnostic but also prognostic or predictive in the future. With machine learning, ECGs will soon be able to detect ventricular dysfunction (measure ejection fraction), predict the risk for developing afib, heart attack, or heart failure in the short term and possibly even the long term.

Medgadget: What challenges and opportunities do you foresee in bringing your technology to wider use?

Dr. Chang: The challenges are the same as everyone else, needing more time and money. It is more so in the tech startup because you are running against the clock, trying to get things done before the money runs out, or before competing products emerge in the market.Our biggest challenges in the market are the amount of efforts needed to educate the doctors and patients, raise brand awareness and demonstrate product effectiveness in improving patient outcomes. We are creating a new product category—12-lead ECG for personal use, which is our biggest opportunity as a market disruptor.

Medgadget: Is it challenging for ECG device companies to scale in revenue?

Dr. Chang: Yes, there are challenges to scale in revenue. Since the ECG is a century-old technology, the differentiation among products often is not so clear; there are also many ECG players out there. Thus, establishing a trustable brand among industry giants such as GE and Philips is a huge obstacle but not insurmountable. As said, we will initially focus on certain niche markets, to generate more product traction and raise brand awareness, then gradually establish ourselves penetration of Xpress ECG into the mass market.