The widespread introduction of coronary computed tomography (CT) angiography now allows for accurate, noninvasive detection of coronary artery disease. This has predominantly focused on patients with symptoms suggestive of coronary artery disease and is now the first-line test of choice for patients with stable chest pain in many parts of the world. This increasing use of coronary CT angiography has lowered the threshold for screening people considered at risk for coronary artery disease, even in the absence of symptoms.
Background:
Coronary atherosclerosis can develop at an early age and remain dormant for many years.
Aim:
Define the characteristics of subclinical coronary atherosclerosis associated with the development of myocardial infarction.
Design:
Prospective observational cohort study.
Setting:
General population study from Copenhagen, Denmark.
Participants:
9,533 asymptomatic people aged 40 years or older without known ischemic heart disease.
Measurements:
Subclinical coronary atherosclerosis was assessed with coronary computed tomography angiography performed blinded to treatment and outcomes. Coronary atherosclerosis was characterized according to luminal obstruction (nonobstructive or obstructive [≥50% luminal stenosis]) and extent (nonextensive or extensive [one-third or more of the coronary tree]). The primary outcome was myocardial infarction and the secondary outcome was a composite of death or myocardial infarction.
Results:
A total of 5,114 (54%) people did not have subclinical coronary atherosclerosis, 3,483 (36%) had non-obstructive disease , and 936 (10%) had obstructive disease . Within a median follow-up of 3.5 years (range, 0.1 to 8.9 years), 193 people died and 71 suffered myocardial infarction.
The risk of myocardial infarction was increased in people with obstructive (adjusted relative risk, 9.19 [95% CI, 4.49 to 18.11]) and extensive disease (7.65 [CI, 3.53 to 16.11]). 57]).
The highest risk of myocardial infarction was observed in people with subclinical extensive obstructive (adjusted relative risk, 12.48 [CI, 5.50 to 28.12]) or nonextensive obstructive (adjusted relative risk, 8.28 [CI]) coronary atherosclerosis. CI, 3.75 to 18.32]).
The risk of the composite endpoint of death or myocardial infarction was increased in people with extensive disease, regardless of the degree of obstruction, such as nonobstructive-extensive (adjusted relative risk, 2.70 [CI, 1.72 to 4.0]. 25]) and obstructive-extensive (adjusted relative risk, 3.15 [CI, 2.05 to 4.83]).
Limitation:
Primarily white people were studied.
Conclusion: In asymptomatic people, subclinical obstructive coronary atherosclerosis is associated with a more than 8-fold increased risk of myocardial infarction. |
Comments
A cohort study of more than 9,000 people found that in asymptomatic middle-aged people without known cardiovascular disease, subclinical obstructive coronary atherosclerosis is associated with a more than 8-fold increased risk of myocardial infarction. The findings are published in Annals of Internal Medicine .
Coronary atherosclerosis is a biological process responsible for the development of myocardial infarction. These conditions together define the clinical syndrome “ischemic heart disease.” Subclinical coronary atherosclerosis precedes ischemic heart disease and can develop at an early age, many years before clinical disease develops. For more than 50 years, obstructive coronary artery disease, defined as luminal coronary stenosis of 50% or more, has been considered a key high-risk feature. However, in recent decades, the extent of atherosclerosis in the coronary tree, as well as the specific morphological characteristics of atherosclerotic plaque, have been recognized as important risk factors.
Researchers from the University of Copenhagen, Copenhagen, Denmark, studied 9,533 asymptomatic people aged 40 years or older without known cardiovascular disease to define the characteristics of subclinical coronary atherosclerosis associated with the development of myocardial infarction. Participants were evaluated using computed tomography angiography (CTA) to diagnose obstructive coronary atherosclerosis.
The authors found that 54 percent of people did not have subclinical coronary atherosclerosis. Among the 46 percent of people diagnosed with subclinical coronary atherosclerosis, 36 percent had nonobstructive disease and 10 percent had obstructive disease. Among people diagnosed with the condition, subclinical coronary atherosclerosis was also found in 61 percent of male participants and 36 percent of female participants.
According to the authors, identification of luminal or extensive subclinical obstructive coronary atherosclerosis provides a potentially clinically relevant incremental risk assessment in patients without suspected or known ischemic heart disease undergoing cardiac CT and/or gated chest CT. by electrocardiogram for other clinical indications.
An accompanying editorial by authors from the BHF Center for Cardiovascular Science, University of Edinburgh highlights that this research provides the opportunity to study the contemporary natural history of coronary artery disease in the absence of intervention, where neither the patient nor the doctor is aware of the findings. of the exploration. The authors add that the study also provides invaluable data on the event rates and prevalence of asymptomatic coronary artery disease that will inform public health prevention strategies and ongoing clinical trials of preventive therapies targeting people screened for coronary artery disease. hidden.
