The Next Imaging Revolution in Interventional Cardiology
Exclusive insights on how non-invasive tools and therapy are leading cardiology imaging from Dr. John Yianni, Partner at Earlybird Health.
The Continual Paradigm Shift in Coronary Imaging
The 1970s marked a transformative period in interventional cardiology, pioneered by the work of German cardiologist and radiologist Dr. Andreas Grüntzig, the father of interventional cardiology. In 1977, Dr. Grüntzig conducted the first angioplasty on an awake patient in Zurich. This innovative procedure combines X-ray imaging with catheters and ballons to effectively treat blocked arteries. Although initially met with scepticism, by the 1990s, angioplasty had become the preferred method for treating coronary artery blockages, surpassing the previously established surgical treatment known as Coronary Artery Bypass Graft (CABG).
In the late 1990s, the concept of vulnerable (or high-risk) plaque transformed our understanding of heart attacks. Previously, X-ray imaging was used to detect blockages and guide interventions. However, it became clear that heart attacks were caused by the sudden rupture of these vulnerable plaques, leading to clot formation and acute blockage of the artery, resulting in a heart attack. X-ray imaging only revealed narrowing and lacked information on plaque stability and its components (lipid, calcium, etc.). Moreover, vulnerable plaques often appeared insignificant on X-ray, yet even minor plaque buildup (e.g., 20% of coronary artery diameter narrowing) could rupture and trigger heart attacks. Thus, there was a need to develop intravascular imaging tools capable of differentiating between stable and unstable plaques. Some of these ground-breaking technologies developed in the decade include:
- Intravascular Ultrasound (IVUS) can assess the plaque using sound (echo) from the inside of the coronary artery and has been used in interventional cardiology to assess heart attack risk by characterizing arterial plaques.
- Optical Coherence Tomography (OCT), demonstrated in vivo in 1993, this advanced optical imaging laser-based technique generates high-resolution cross-sectional tissue images.
- Intracoronary Near-Infrared Spectroscopy (NIRS) is a novel catheter-based imaging modality able to detect atherosclerotic lipid-rich lesions within the coronary arteries.
By the year 2000, witnessing such major advancements in the field, the New England Journal of Medicine awarded intra-arterial diagnostic imaging as 1 of the 10 most important advances of the past millennium.
A third revolution, this time in non-invasive imaging, is currently underway, focusing on identifying the extent of coronary artery disease through advanced imaging techniques that do not require an invasive procedure. These methods aim to both stable and unstable plaques, potentially leading to the administration of local and systemic treatments.
The first aim is to identify individuals at risk for heart attacks and enhance prevention strategies. Although finding a suitable treatment for unstable plaques remains a challenge, potential solutions for plaque characterization are emerging, surpassing traditional X-ray methods.
Moreover, recent advancements in non-invasive imaging offer cardiologists the ability to determine the necessity of intervention or treatment without resorting to invasive procedures. For example, AI analysis of Computed Tomography (CT) scans enables accurate identification and localization of plaques’ addition the CT scans can be processed using a technique called Computed Tomography-Fractional Flow Reserve (CT-FFR), which measures blood flow in the artery and assists in determining the need for a stent, a metallic prothesis used to unblock coronary arteries. The ultimate goal is to define effectively the need for the best treatment without any invasive diagnostic procedure.
In this piece, we delve into the latest revolution in cardiovascular imaging. Through a Q&A session, we gain insights from Dr. John Yianni, Earlybird Health Partner, who has been involved in the development of this field for more than twenty years. John shares why non-invasive tools have the potential to dominate the cardiovascular imaging field and guide therapy, both with local-based device treatment and drugs.
John has founded several successful startup companies over the years and has invested in healthcare companies with Earlybird VC since 2016. John holds a doctorate in Biophysics.
Q1. What do we consider imaging in the medical field?
Medical imaging refers to the techniques and processes used to create images of the human body (fully or parts of it) for different clinical purposes, from medical procedures and diagnosis to medical science (i.e., the study of anatomy and function).
There are two types of modalities for imaging:
- Invasive, if the device is introduced into the patient’s body for diagnosis and treatment. This is associated with risks.
- Non-invasive, if the device is external and there is no intervention (no break in the skin).
I believe non-invasive methods will constitute the future of imaging in interventional cardiology, revolutionising the diagnosis and management of coronary artery disease. As time passes, I think scans will replace invasive imaging as a first step to diagnosing coronary artery disease.
We are already seeing this transformation with the processing of images from CT scans, giving information to cardiologists about flow in arteries and the degree of stenosis that can determine whether a patient requires a stent. The ability to characterise elements such as coronary plaque within the vessel wall will also provide important information for cardiologists to determine the risk of heart attack and how patients should be managed, for example with drugs, or coronary intervention with treatments such as vascular cryotherapy, stents or other localised therapies.
These two factors will contribute to early disease detection and increase positive outcomes. For example, if a test reveals coronary artery inflammation, the patient may be recommended to take certain drugs to prevent future heart attacks, reducing the risk of this cardiac event.
Q2. What are the pros and cons of non-invasive imaging?
Non-invasive imaging has a multitude of advantages.
As I mentioned before, non-invasive imaging is less risky and burdensome to patients and can be performed faster and more efficiently, unlocking the potential for more preventive screenings. At this moment, all the medical specialities around have recommended CT as the best test for patients with suspected coronary artery disease.
In addition, if an AI-powered imaging approach is implemented, we might be able to provide more information on the state of patients with a better resolution. In the cardiac field alone, we will have access to:
- The extent of coronary artery disease.
- The level of arterial inflammation.
- Whether patients are at risk for a cardiac event (i.e., heart attack).
- Whether stenosis is occurring and subsequently how urgently a stent is needed.
I also do not believe physicians will be sceptical of using new approaches, provided that clinical validation is available and data are reviewed. For this reason, I expect an increase in the number of papers studying imaging and the correlation between processed images and diagnoses.
A common critique is that by promoting screenings, patients will be exposed to more radiation. However, regulations are already in place to prevent any adverse risks. Furthermore, modern technologies produce less radiation per scan than ever before, and only high-risk patients may need more than one test per year to monitor the disease and its progression.
In my opinion, the main downside of the non-invasive imaging approach is the high cost of the scanners. Developing and emerging countries might struggle to purchase them, and patients in certain regions might have to wait longer to access these technologies.
Q3. Why is non-invasive imaging particularly important in the cardiovascular field?
Around 17.9 million people die each year from cardiovascular diseases, accounting for 32% of global deaths. More than four out of five deaths from cardiovascular diseases are caused by heart attacks and strokes.
When it comes to heart attacks, patients may not exhibit any symptoms before the cardiac event. Some risk factors, such as high blood pressure, cannot be “felt.” Non-invasive imaging technologies show great promise in detecting additional risks, such as arterial stenosis and inflammation. By combining all this information, doctors can make treatment decisions even before the first symptoms arise.
Research suggests that a high percentage of heart attack deaths can be avoided when imaging tests are performed on patients in their 40s and medications are prescribed to those at risk.
I believe non-invasive imaging technology will play a key role in fighting cardiovascular diseases and other conditions, and a preventative approach will make a significant difference.
Q4. You see many companies in this space. What are the ones we should be looking at?
At Earlybird Health, we are witnessing a rise in the number of companies creating non-invasive alternatives; notable companies include:
Elucid Bioimaging is a MedTech company based in Boston. To support personalized patient care, they offer a non-invasive AI software that quantifies atherosclerotic plaque characteristics in comparison to histopathology.
In New York, the AI-based digital care platform Cleerly Health employs Coronary Computed Tomography Angiography (CCTA) imaging to precisely assess heart disease by measuring and categorising plaque accumulation in the heart.
On the West Coast, in California, HeartFlow, Inc. provides a non-invasive personalized cardiac test called HeartFlow Analysis. It utilizes coronary physiologic simulation software to aid physicians in the functional evaluation of coronary artery disease.
Shifting the focus to the European scene, we find Oxford-based Caristo Diagnostics. Their CE-certified technology, CaRi-Heart®, aims to improve the accuracy of routine cardiac Computed Tomography (CT) scans and provide more precise predictions of an individual’s cardiovascular risk. This enables physicians to prescribe highly personalized and more effective treatments.
Medis Medical Imaging is a second notable company that originated as a spin-off from Leiden University Medical Centre in the Netherlands. Over several years they have been developing software post-processing solutions to assist cardiovascular imaging across various modalities such as MRI, CT, X-ray angiography, and intravascular ultrasound.
Q5. What is one piece of advice for companies in this field?
One important recommendation for companies in this field is to keep focusing on advancing non-invasive imaging technologies combined with AI software to allow advanced interpretation of data.
Additionally, companies developing interventional and therapeutic approaches to treating inflamed plaque should integrate their therapies with non-invasive imaging in order to first characterise the disease, in the case of local treatments, as a means to guide therapy, and also follow the progression of the disease over time.
Q6. What do you think is still missing in the field of non-invasive cardiovascular imaging?
What is missing is what we do with the information; the system needs to catch up with the innovation.
How does the imaging data guide therapy? For detecting flow and stenoses that need treatment — well that’s the obvious place to start in terms of the consequences of having the imaging information available.
In the medium term, plaque characterization can have a massive impact on how patients are monitored over time for their coronary artery disease, and also to prevent events such as heart attack from happening in the first place by facilitating the choice of the most appropriate treatment.
For example, in the case of localized therapy, the imaging data can guide to exactly where that therapy needs to be applied. This will take some time because clinical trials linking imaging with therapy need to be done and there is debate over what that therapy might or should be, with a number of approaches being evaluated for their potential to treat coronary artery disease — this involves both devices and therapeutics.
Reimbursement issues will of course have to be addressed as well but in time imaging will go hand in hand with therapy and ongoing monitoring of patients. So with the benefit of these technologies and the processing of the images to characterize coronary artery disease, the subsequent positive impact on how we detect, treat and monitor coronary artery disease will be immense.
Are you a founder of a company in this field or with applications in the cardiovascular area — whether imaging or treatment?
We at Earlybird Health would love to hear more about your work — do not hesitate to get in touch with our team at health@earlybird.com and pitch your opportunity here!
Thanks to Danny Detiège, Dr. Carlos Collet, and Dr. Christoph Massner for their review and thoughtful input into the above discussion and also Elena Marchesi for her editing.
