Arrhythmias

Revolutionizing Cardiac Care

Arrhythmias

The most common cardiac arrhythmia is atrial fibrillation (AF). One in four will get it in the course of their life, the probability increases especially from the age of 65, as well as from 55 years with the presence of other risk factors (e.g. high blood pressure, diabetes, previous cardiovascular events) [1]. AF is one of the major causes of stroke, heart failure, sudden death and cardiovascular morbidity, and is associated with poor quality of life and averse symptoms. However, Cardiac arrhythmias are not always noticeable, often occur only occasionally and are therefore sometimes difficult to detect in the doctor's office (e.g. by means of an ECG) [2]. In many patients, AF progresses from short, infrequent episodes to longer and more frequent attacks. Over time, many patients will develop sustained forms of AF. 

    

Atrial Fibrillation Detection

Corsano CardioWatch 287-2 incorporates a multi-faceted approach to health monitoring, leveraging both photoplethysmography (PPG) and electrocardiogram (ECG) technologies. Corsano CardioWatch detects atrial fibrillation (AFib) continuously using PPG. Once an AFib episode is detected, the Corsano App prompts the patient to perform an ECG.

Continuous AFib Detection: Corsano CardioWatch 287-2 uses its PPG sensors to continuously monitor the blood volume changes in the microvascular bed of tissue. This is done by emitting light into the skin and measuring the amount of light either absorbed or reflected back. The variations in light absorption or reflection are influenced by blood flow changes, which occur with each heartbeat.

Detecting Irregularities: The PPG data is analyzed to identify patterns that may suggest irregular heart rhythms, such as AFib. AFib can cause rapid, irregular heartbeats, which can be detected as abnormal patterns in the PPG signal.

Alert Generation: When the Corsano Bracelet detects an irregular rhythm suggestive of AFib through its PPG monitoring, the Corsano App will issue an alert to the patient. This alert indicates that an abnormal pattern has been identified and further investigation is needed.

ECG Confirmation: Upon receiving an alert, the patient is prompted to perform an ECG using the Corsano Bracelet. To do this, the patient needs to touch the metal frame of the Corsano Bracelet to perform the ECG recording. This step is critical because while PPG is useful for continuous monitoring and detecting potential irregularities, ECG is the gold standard for diagnosing AFib and other cardiac arrhythmias. The ECG provides a detailed view of the electrical activity of the heart, allowing for a more accurate diagnosis.

Data Analysis and Reporting: The ECG data collected is then analyzed, potentially using an advanced algorithmic analysis to confirm whether AFib or another arrhythmia is present. Based on this analysis, an ECG Report is provided by the Corsano CardioWatch System in the Web Portal.

The figure depicts a preview for a patient with Paroxysmal Atrial Fibrillation. PPG and ECG functionality was validated during the REmote CArdiac MOnitoring (RECAMO) clinical trial in the Reinier de Graaf Hospital. 160 Patients were included for a 30 days monitoring period.

    

Atrial Fibrilation & Stroke

Every year, millions of patients experience symptoms potentially associated with cardiac arrhythmias, a condition in which the electrical impulses that coordinate heartbeats do not occur properly, causing the heart to beat too quickly, too slowly or irregularly. Examples of arrhythmias include supra ventricular arrhythmias, which are fast heart rates that originate from the upper chambers of the heart, atrial tachycardia, atrial flutter and AF. The symptoms of arrhythmias include palpitations or a skipped heartbeat, rapid heartbeat, shortness of breath, dizziness, light-headedness, fainting spells, vertigo, anxiety and fatigue or no symptoms at all. Early detection is essential in order to obtain early treatment and help avoid more serious medical conditions, such as stroke, and additional medical costs.

AF causes high risk of stroke [3]. Stroke is a major disease that affects the ability of blood vessels to carry oxygen to the brain due to clotting and ruptures. According to the d European Society of Cardiology, strokes are globally the second- leading cause of death and the leading cause of complex disability in adults. In Europe, estimates predict that over the next 15 years we will see an increase of 35% of stroke cases due to larger ageing populations. While death rates have been in decline, the costs of caring for stroke survivors is rising due the average lifespan rates rising [4].

There are two major risk factors of stroke: Hypertension or high blood pressure, and undetected atrial fibrillation, or AF. Approximately one-third of all stroke cases are linked to complications from atrial fibrillation. Atrial fibrillation is not a permanent condition, it comes and goes, and in 50% of the cases you don’t feel anything, and in some cases you only have some accelerated heart rhythm. Due to this unpredictability, it’s highly difficult to diagnose on time.

In patients with AF, the upper chambers of the heartbeat irregularly and blood does not flow properly to the lower chambers of the heart. The AHA estimates that AF affects as many as six million patients in the United States and 33.5 million patients worldwide. The NSA estimates that one-third of AF patients are asymptomatic and still undiagnosed. More than 750,000 hospitalizations occur each year because of AF, and the condition contributes to an estimated 130,000 deaths each year [5]. Since AF is more common among people over the age of 60, these numbers are expected to increase as the U.S. population ages.

In addition, AF is the leading risk factor for stroke because AF can cause blood to collect in the heart and potentially form a clot, which can travel to the brain potentially resulting in an ischemic stroke. While individuals with AF are approximately five times more likely to suffer a stroke, the NSA estimates that up to 80% of strokes in people with AF can be prevented through early detection and proper treatment. According to the AHA, stroke costs the United States an estimated $34 billion each year in healthcare costs and lost productivity, and is a leading cause of serious long-term disability. The AHA estimates that ischemic strokes represent 87% of all strokes in the United States and that between 15% and 20% of the estimated 690,000 ischemic strokes are attributable to AF [6].

Yet there is hope, because when atrial fibrillation is diagnosed it can be very effectively treated by using anti-coagulant drugs, which thin the blood and prevent the creation of blood clots. Up to 80% of these strokes are avoidable with early and efficient detection.

Early detection of AF is critical in optimizing patient care, delivering earlier treatment to help avoid further adverse clinical events, managing symptoms caused by AF, and reducing the total public health burden of treating stroke. The AHA and American Stroke Association (“ASA”) have published treatment guidelines for patients diagnosed with AF to manage heart rhythm and rate and prevent stroke. These early treatments include:

  • medications such as oral anticoagulants
  • treatment with anti-arrhythmic drugs
  • interventions such as cardiac ablation therapy to help control heart rhythm and rate

Atrial fibrillation burden, the amount of time a patient spends in AF during a monitoring period, has been identified in the clinical community as an important measure for determining appropriate and effective therapeutic interventions to manage patients with AF and assessing stroke risk. The calculated AF burden is dependent on data available for analysis during the monitoring period. Since the most common type of AF occurs intermittently, long-term continuous monitoring with Corsano Cardiowatch 287-2 more accurately measures AF burden because every heartbeat is recorded without interruption during the entire monitoring period.

Replacing ILR

The Corsano CardioWatch System represents an innovative approach to cardiac monitoring that could potentially complement or, in certain contexts, replace traditional implantable loop recorders (ILRs).

While ILRs offer long-term monitoring (typically up to three years), they require a minor surgical procedure for implantation. ILR costs are significant. Corsano CardioWatch provides a non-invasive alternative that might be more acceptable to some patients, especially those at lower risk or those who are hesitant about implantation.

Corsano CardioWatch offers a valuable screening tool, identifying individuals who might benefit from further investigation or direct intervention. In some cases, CardioWatch might be used in tandem with ILRs, providing additional data points or serving as a preliminary monitoring step before deciding on ILR implantation.

References

  1. Kirchhof et al., ESC Guidelines for the management of atrial fibrillation, European Heart Journal 2016
  2. Freedman, J Camm et al. Screening for Atrial Fibrillation. Circulation. 2017;135:1851-1867
  3. Wolf PA, et al., Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke. 1991;22:983ñ988.
  4. Nichols M TN, Luengo-Fernandez R, Leal J, Gray A, Scarborough P, Rayner M European Cardiovascular Disease Statistics 2012. European Heart Network, Brussels, European Society of Cardiology, Sophia Antipolis 2012.
  5. Indranill Basu Ray, Sumit K. Shah; Formulating a More Comprehensive Stroke-Risk Evaluation Scale. Tex Heart Inst J 1 June 2018; 45 (3): 168–171.
  6. Bruce Ovbiagele, MD, MSc, MAS, FAHA, Chair; Larry B. Goldstein, MD, FAHA; Randall T. Higashida, MD, FAHA; Virginia J. Howard, PhD, FAHA; S. Claiborne Johnston, MD, PhD; Olga A. Khavjou, MA; Daniel T. Lackland, DrPH, MSPH, FAHA; Judith H. Lichtman, PhD; Stephanie Mohl, BA; Ralph L. Sacco, MD, MSc, FAHA; Jeffrey L. Saver, MD, FAHA; Justin G. Trogdon, PhD, Forecasting the Future of Stroke in the United States
  7. Reynolds K, Yang J, et al. Association of Burden of Atrial Fibrillation With Risk of Ischemic Stroke in Adults With Paroxysmal Atrial Fibrillation: The KP-RHYTHM Study. JAMA Cardiol. 2018;3(7):601–608. doi:10.1001/jamacardio.2018.1176