Chronic infarct size after spontaneous coronary artery dissection: implications for pathophysiology and clinical
Abtehale Al-Hussaini1, Ahmed M S E K Abdelaty1,2, Gaurav S Gulsin1
1Department of Cardiovascular Sciences, NIHR Leicester Biomedical Research Centre, University of Leicester, Glenfield Hospital, Groby Road, Leicester LE3 9QP, UK.
Insights
Spontaneous coronary artery dissection (SCAD) survivors typically have small myocardial injuries and preserved heart function. However, STEMI presentation, poor initial flow, multivessel SCAD, and connective tissue disorders predict larger infarcts.
Area of Science:
- Cardiology
- Cardiovascular Imaging
- Medical Diagnostics
Background:
- Spontaneous coronary artery dissection (SCAD) is a cause of myocardial infarction, particularly in young to middle-aged women.
- Understanding the extent of myocardial injury and its impact on cardiac function post-SCAD is crucial for patient management.
- Cardiac magnetic resonance imaging (CMR) provides detailed assessment of myocardial damage and left ventricular function.
Purpose of the Study:
- To quantify myocardial injury extent and distribution using CMR in SCAD survivors.
- To evaluate the impact of SCAD on left ventricular systolic function.
- To identify predictors of significant myocardial injury in SCAD patients.
Main Methods:
- A case-control study involving 158 SCAD survivors and 59 healthy controls, all assessed by CMR.
- Phenotyping included assessment of myocardial infarct size, late gadolinium enhancement (LGE), and left ventricular ejection fraction and dimensions.
- Multivariate logistic regression was used to identify predictors of larger infarcts (>10% LV mass).
Main Results:
- SCAD survivors showed generally preserved left ventricular function, with small reductions in ejection fraction and slight increases in ventricular dimensions compared to controls.
- The majority of SCAD patients had small infarcts (median 4.06% LV mass), with 39% having no detectable LGE.
- Predictors of larger infarcts included ST-elevation myocardial infarction (STEMI) at presentation, initial TIMI 0/1 flow, multivessel SCAD, and a Beighton score >4.
Conclusions:
- Most SCAD patients experience limited myocardial infarction and maintain preserved ejection fraction.
- Patients with STEMI, poor initial coronary flow, multivessel SCAD, or features of connective tissue disorders are at higher risk for significant myocardial injury.
Aims:
To report the extent and distribution of myocardial injury and its impact on left ventricular systolic function with cardiac magnetic resonance imaging (CMR) following spontaneous coronary artery dissection (SCAD) and to investigate predictors of myocardial injury.
Methods And Results:
One hundred and fifty-eight angiographically confirmed SCAD-survivors (98% female) were phenotyped by CMR and compared in a case-control study with 59 (97% female) healthy controls (44.5 ± 8.4 vs. 45.0 ± 9.1 years). Spontaneous coronary artery dissection presentation was with non-ST-elevation myocardial infarction in 95 (60.3%), ST-elevation myocardial infarction (STEMI) in 52 (32.7%), and cardiac arrest in 11 (6.9%). Left ventricular function in SCAD-survivors was generally well preserved with small reductions in ejection fraction (57 ± 7.2% vs. 60 ± 4.9%, P < 0.01) and increases in left ventricular dimensions (end-diastolic volume: 85 ± 14 mL/m2 vs. 80 ± 11 mL/m2, P < 0.05; end-systolic volume: 37 ± 11 mL/m2 vs. 32 ± 7 mL/m2, P <0.01) compared to healthy controls. Infarcts were small with few large infarcts (median 4.06%; range 0-30.9%) and 39% having no detectable late gadolinium enhancement (LGE). Female SCAD patients presenting with STEMI had similar sized infarcts to female Type-1 STEMI patients age <75 years. Multivariate modelling demonstrated STEMI at presentation, initial TIMI 0/1 flow, multivessel SCAD, and a Beighton score >4 were associated with larger infarcts [>10% left ventricular (LV) mass].
Conclusion:
The majority of patients presenting with SCAD have no or small infarctions and preserved ejection fraction. Patients presenting with STEMI, TIMI 0/1 flow, multivessel SCAD and those with features of connective tissue disorders are more likely to have larger infarcts.
Related Concept Videos
01:19Acute Coronary Syndrome II: Pathophysiology and Clinical Manifestations
01:26Coronary Artery Disease II: Pathophysiology
01:26Aneurysm III: Interprofessional Care
01:28Acute Coronary Syndrome IV: Interprofessional Care
01:30Acute Coronary Syndrome I: Introduction
01:30Acute Coronary Syndrome III: Diagnostic Studies