NIMBLE Diagnostics: Non-invasive medical technology used to monitor patients with implanted coronary stents


Societal challenge: No method for proactively monitoring implanted stents

NIMBLE Diagnostics’ novel technology will make waves in the medical community and in the treatment of cardiovascular disease. Atherosclerosis is the leading cause of most cardiovascular diseases, as it often forms blood clots and causes a restriction of oxygen-rich blood flow to the tissues. This blockage can cause various diseases, such as coronary artery disease, stroke, peripheral arterial disease, and aneurysms.

Stents are small, metallic tubes implanted in the location of the obstruction to restore blood flow or other fluids. Initially, they were only used to solve cardiovascular problems, but their use has been extended to other biliary, urinary, tracheobronchial, and gastrointestinal disorders. Worldwide, it is estimated that more than 50 million people have implanted stents, and each year an additional 4 million are implanted in often life-changing treatment.

Stent related problems

However, after stent implantation, different pathological processes and problems can lead to life-threatening situations for the patient with implanted stent/s. The two most relevant are restenosis (in-stent restenosis or ISR), thrombosis (stent thrombosis or ST), and fracture (stent fracture or SF). These processes occur in over 30% of implanted stents.

It is very difficult to diagnose stent malfunction early as in most cases the symptoms only appear after the stent is 90% dysfunctional. At this stage the stent is unable to perform its function, thereby increasing the incidence of serious complications, such as strokes, heart attacks, or sudden death.

Currently, there is no preventive standard of care for the follow-up and management of patients with implanted stents. Although there are different diagnostic imaging techniques, the gold standard of care still requires confirmation with a costly invasive surgical procedure called catheter angiography, involving anesthesia, X-ray exposure, and 24h hospitalization recovery. This complex procedure is only used after symptoms appear and is not appropriate for recurrent follow-up. It does not allow healthcare professionals to act before the dangerous symptoms have appeared. Therefore, current patient management is based on symptoms and does not allow prevention, leading to acute symptoms, life-threatening situations, and increasing healthcare expenditure.

NIMBLE Diagnostics deep-tech unique innovation: Non-invasive and non-ionizing stent monitoring for early detection of stent malfunction


At NIMBLE Diagnostics, we have developed the NIMBLE System, a novel non-invasive and non-ionizing medical device for monitoring symptomatic and asymptomatic patients with implanted stents.

NIMBLE is portable and can be introduced at different points of the patient journey and settings: 1) At Hospitals for the triage of patients presenting acute symptoms; or 2) After stent implantation for the verification of stent function and safe patient discharge; and 3) At Primary Care/Private Clinics for follow-up of patients and the personalization of treatment.

Our technology is based on Microwave Spectrometry (MWS), a frequency scanning procedure. The stents have a metallic structure with a characteristic electromagnetic resonance which can be detected in real-time by MWS in a painless procedure. The analysis of the scattered radiation provides information on two main parameters: 1) The stent environment and 2) Stent geometry. This information makes it possible to accurately measure and quantify stent malfunction non-invasively, allowing patient monitoring and follow-up over time.

Current standard of care cannot offer proactive stent monitoring

Currently, clinical practice is symptom-driven and does not allow preventive and personalized care. Although tools available in clinical practice include different non-invasive diagnostic imaging techniques (ultrasonography, CT, or MRI), they are still very complex and costly, require image interpretation, and can only be used in hospital settings. Additionally, they have limited accuracy, with many false positive results. Therefore, the results must be confirmed with invasive catheter angiography (gold standard). These problems result in the fact that they are not used to monitor stent status proactively in clinical practice.

NIMBLE Diagnostics: Excellent results so far, with more milestones ahead

NIMBLE technology is currently positioned at TRL5, with an MVP ready for clinical validation. To date, we have obtained excellent results in assessing the stent status in vitro, ex vivo, and in vivo to demonstrate that our technology is able to detect several stent malfunctions (restenosis or blockages, fractures, and collapses) in a fast, easy and non-invasive way.

Next steps: All R&D activities have resulted in a system that accurately measures and quantifies non-invasive stent malfunction in vivo. However, further steps are needed before we can offer our technology to clinicians:

  • Technological: Complete the prototype of the medical device and pre-series manufacture of the prototypes that will be used during the human clinical trial.
  • Clinical Validation:  Validate NIMBLE Diagnostics’ system in a human clinical trial to evaluate the effectiveness and efficacy of the technology.
  • Regulatory, Safety, Quality, and Compliance: Undergo a conformity assessment procedure for the CE certification of NIMBLE, including the assessment of the Quality Management System (QMS) and of the technical documentation. In the US, a 510(k)-application submission will be addressed.

Positive Societal and environmental impact

Stent malfunctioning is a leading cause of morbidity and mortality, posing a large burden globally. Accordingly, it not only affects the patient with implanted stents but also has a devastating impact on caregivers and healthcare systems. NIMBLE Diagnostics can significantly reduce this burden by providing a novel non-invasive and non-ionizing approach for the monitoring of stent malfunction.  NIMBLE will achieve this impact by:

  • Prevention and early diagnosis of stent-related problems. Avoidance of severe outcomes (25% of heart attacks and 65% of premature deaths) that can become chronic and bear physical/neurological sequels, and reduction of 37% of hospitalizations ($9B in savings). Reduction of work productivity losses both for the patient and caregivers.
  • Support decision-making in the different steps of the patient journey. Clinicians can make informed decisions and decide the best course of action.
  • Personalization of the pharmacological treatment. Optimization of drug spending as well as reduction of adverse events ($1.2B in savings).
  • Avoidance of non-productive angiographies ($5.7B in savings) and reduction of waiting lists by moving visits to primary care. 

In the current context of resource scarcity, the introduction of NIMBLE Diagnostics’ novel technology has a clear impact on optimizing resource use and improving healthcare efficiency, as well as having a clear benefit for patients, healthcare professionals, and caregivers. Therefore, NIMBLE will result in a notable societal transformation once implemented.