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Posted on Friday March 15, 2024 in Health Screening
An article by Dr Edward Leatham, Consultant Cardiologist.
Coronary heart disease is a significant health concern that affects many individuals worldwide. It arises from the buildup of LDL (low-density lipoprotein) rich plaque within the walls of the coronary arteries. These arteries, crucial for supplying blood to the heart muscle, are relatively small, with diameters ranging from 2 to 4mm, and are located on the heart’s surface. Imaging these arteries in a beating heart presents unique challenges due to their movement and size.
Advancements in computed tomography (CT) technology have significantly improved our ability to visualize the coronary arteries. Noninvasive cardiac CT scans, enhanced with contrast agents injected into the arm’s vein, allow for detailed imaging and reconstruction of these arteries, facilitating the creation of an angiogram.
However, interpreting CT images can be complicated due to movement artifacts and the presence of calcific plaque, which can block x-rays and lead to overestimation of arterial blockage. This is particularly problematic because the decision to perform a coronary intervention, such as placing a stent, often hinges on whether a vessel is more than 60-65% blocked. Since atherosclerosis progresses slowly, determining the necessity of intervention for vessels with blockages in the 60-70% range can be challenging.
This uncertainty leads to a significant number of patients being referred for invasive angiography, a more sensitive test, which sometimes reveals no flow-limiting issues, rendering the invasive procedure unnecessary. Invasive angiography, requiring hospital admission, carries its risks, underscoring the need for more precise noninvasive diagnostic tools.
The development of a computational model by researchers at Stanford University marked a significant breakthrough in noninvasive coronary flow assessment. This model correlates with the catheterization laboratory’s gold-standard fractional flow reserve (FFR) test, providing a valuable tool for cardiologists.
Since 2016, cardiologists have been utilising the HeartFlow Analysis in conjunction with cardiac CT scans to enhance the accuracy and predictive value of noninvasive coronary imaging. This technology allows many patients to avoid unnecessary invasive angiography, reducing the associated risks and stress.
For the HeartFlow Analysis to be effective, high-quality CT images are necessary. These images are anonymized and uploaded to HeartFlow’s platform, where advanced algorithms, including deep learning, analyze the data to create a flow map. This map is color-coded and superimposed over a 3D model of the patient’s coronary arteries, providing a detailed visualization of blood flow and potential blockages.
The processed data is then returned to the reporting team and the referring cardiologist, who combine this information with their clinical expertise to make informed decisions regarding patient care.
This process is streamlined and enhances the diagnostic pathway for patients undergoing cardiac CT. By integrating HeartFlow Analysis, healthcare providers can assure patients of the reduced likelihood of unnecessary catheterization lab visits, focusing on interventions only when absolutely necessary.
In summary, CT FFR, particularly through the HeartFlow Analysis, represents a significant advance in the noninvasive diagnosis and management of coronary heart disease. It exemplifies the power of integrating cutting-edge technology with medical expertise to improve patient outcomes and reduce the need for invasive procedures.
The idea of predicting a heart attack may have once seemed like science fiction, but it is rapidly becoming a reality. With the advent of advanced imaging techniques and artificial intelligence, we are now able to detect the early signs of coronary heart disease and intervene before a heart attack occurs. This represents a major shift in the way we approach cardiovascular care, moving from a reactive model to a proactive one.
Is is increasingly obvious that not everyone with raised coronary inflammation and elevated risk of heart attack simply has a raised LDL Cholesterol- in fact there appears to be a mixed bag of risk factors associated with high coronary artery inflammation, including raised LDL, raised LP (a), raised Homocysteine, hypertension and dysregulated glucose. Our metabolic health assessment is therefore designed to offer a comprehensive dive into known contributory causes, the latest and most controversial of which is 'glucose dysregulation', the principle topic of this article.
For patients who have been diagnosed with an acute coronary syndrome, requiring bypass surgery or stent, or have CT Angiography and or raised FAI, the latest European and UK guidelines reflect the finding that there is no lower limit for LDL yet discovered, basically meaning the lower the better. These recommendations come after new trials with lower targets showed better outcomes. As a result, millions of people around the world need to be looking more carefully at whether they are taking sufficient medication to lower their LDL to these new targets, for the very best outcomes to be achieved.
Ultimately, the approach to cardiac CT screening is highly individualized, reflecting the diverse presentations and risk factors among patients. By employing a sophisticated pre-consultation process, cardiologists can tailor their assessment and management plans to best suit each patient's unique needs, enhancing the precision and effectiveness of cardiac care.
There are two main reasons left atrial thrombus forms then detaches to cause embolic stroke. The first is that during atrial fibrillation or flutter, a thrombus may develop in the left atrial appendage, which does not move as much as it does when in sinus rhythm. The likelihood of this occurring in any given year is low, correlated to the CHA2DS2-VASc score. The second reason is not related to CHA2DS2-VASc score
Written by Dr Edward Leatham, Consultant Cardiologist: Our metabolic health screen incorporates data processing to provide feedback to the patient on their GV status, using both graphical and numerical stats.
Mammalian hearts, including humans, feature two atria - the left and the right. These chambers serve as reception areas, collecting blood before it's dispatched to the ventricles. This system bears a resemblance to a turbocharger in an engine, where the atria boost the heart's efficiency, preparing it for a powerful contraction.
Recognition that significant coronary artery disease exists without calcification led to the wider user of contrast-enhanced CT scans to detect both calcified and noncalcified plaques. Even more advanced scans identify not only the non calcified plaques, but also areas of inflammation (using data processing to measure FAI), that a non-contrast CT (such as a CAC scan) would otherwise miss. Sequential CAC to follow up disease progression quickly established that an increase in CAC with age was inevitable in most patients and not linked to clinical course, so is not widely practiced.