Atherosclerosis is the buildup of cholesterol, fats, and other substances in the walls of your arteries. These build-ups are referred to as plaque, which cause narrowing of the arteries that can eventually reduce blood flow.
Coronary artery calcium (CAC) analysis helps identify coronary atherosclerotic plaque, which is a strong predictor of an individual’s risk of developing coronary heart disease (CHD) and cardiovascular disease (CVD).
Stady: Coronary calcium dispersion and the cause of specific mortality. Image credit: picmedical/Shutterstock.com
CAC score models and risk prediction have been incorporated into clinical practice guidelines to better understand the potential incidence of a particular disease.
CAC intensity was found to be inversely associated with cardiovascular events and cardiovascular disease. Several treatments are designed to minimize these events. For example, statin treatment increases CAC by forming a denser layer, which indicates stabilization.
Similar to the CAC score, the Agatston score is commonly used to predict CVD events. The ability to predict the Agatston score could be improved by quantifying and identifying the number of vessels affected by atherosclerosis. Thus, overall assessment of CAC distribution and amount of calcified plaque improves the ability to predict the Agatston score.
lately American Journal of Cardiology In the study, the scientists determine whether an estimate of CAC dispersion, based on the number of calcified vessels or the phenotype of CAC, can identify all causes and causes of specific deaths.
The current study used the CAC Consortium, a cohort, retrospective study consisting of 66,636 participants from institutions located in Ohio, Minnesota, and California.
All study participants were adults and presented with asymptomatic CHD. Importantly, participants whose CAC scores were above zero were included in this study.
Furthermore, study participants with a CAC score greater than two for the prevalence analysis index (ID) were included. This analysis accounts for how much each vessel contributed to the Agatston total score, which was associated with all cause and cause-specific mortality.
From the CAC consortium, a total of 28,147 participants, 25% female and 75% male, average age 58 years, met the eligibility criteria. CAC scans of the participants were obtained with multidetector computed tomography or electron tomography. Calcium score was measured quantitatively using the Agatston method.
More than 34% of the group contained calcium in one bowl, 27% in two bowls, and 38.7% in three or four bowls. Typically, older, male, and non-white individuals showed calcium in multiple vessels.
CAC dispersion, defined by vessel number or ID phenotypes with respect to cause-specific mortality, was analyzed using a retrospective cohort. The proportion of participants increased with the participation of three or four vessels with an increase in CAC strata. The diffuse phenotype was more closely associated with an increased risk of CVD-related mortality than the concentrated phenotype.
Previous studies on coronary CT angiography demonstrated the importance of this non-invasive technique for the detection of multivessel disease among diabetic and hypertensive patients. Interestingly, the current study observed that individuals with diabetes, high blood pressure, hyperlipidemia, or current smokers had an increased number of calcium-containing vessels. This finding was also validated in autopsy data, which revealed high-grade multivessel atherosclerosis in 58% of diabetic patients.
Consistent with previous reports, the current study revealed increased vessel involvement to be a poor prognostic marker among those with calcified coronary vessels.
Recently, the Cardiovascular Computed Tomography Society developed a method for incorporating vessel numbers into CAC reports, which is known as the CAC-Data Reporting System (CAC DRS). This system offers a standardized approach to reporting the Agatston score or visual rating by vessel number.
The main importance of this initiative lies in the accurate prediction and prognosis of CVD and CHD events. For example, increased CAC DRS scores indicate the need for immediate modification of the risk factor and the introduction of more intensive therapies.
The authors recommend additional inclusion of CAC dispersion and total CAC scores in the reports, indicating an approximate total plaque burden.
Ultimately, knowledge about the overall plaque burden in the blood vessels will help clinicians make the proper diagnosis and design the right treatment for the patient. Previous studies revealed that the overall burden of plaques is a prominent predictor of subsequent cardiovascular death.
A strong association was observed between conventional diseases such as diabetes and hypertension and prevalent CAC distribution based on race and sex. Vessel number has also been associated with increased mortality from CHD, CVD, or any cause.
In this study, the authors recommend that details of CAC distribution be incorporated into future CAC score algorithms to improve the clinical management of CVD events.
- Dudom, R.; Dardari, Z. Feldman, D. et al. (2023) Coronary artery calcium dispersion and the cause of specific mortality. American Journal of Cardiology 191; 76-83. doi: 10.1016/j.amjcard.2022.12.014