EditorialThe Mystery and Enigma of Spontaneous Coronary Artery Dissection☆
Section snippets
Pathophysiology
Spontaneous coronary artery dissection results from a spontaneous tear in the intima of a coronary artery with a classical ‘intimal flap’ being evident by angiography, giving rise to the appearance of two lumens (true and false). This typical ‘inside-out mechanism’ results in an IMH that may also lead to an intraluminal thrombus. Alternatively, SCAD can be due to an IMH without intimal tear as a result of rupture of vasa vasora. With this ‘outside-in’ mechanism, there is no communication
Precipitating Factors
Risk factors for SCAD include intense physical exercise (isometric or aerobic), Valsalva manoeuvre (e.g., retching, vomiting, bowel movement, coughing), pregnancy (most commonly in the peripartum period) and/or a history of miscarriages, bereavement or other major stress, drug use (mainly cocaine), hormone therapy (oestrogen, progesterone, β-HCG, testosterone, corticosteroids), or coronary artery spasm, whereas the presence of joint hypermobility (present in ∼30% of SCAD cases [10]), velvety
Presentation
As with other causes of ACS, SCAD presents classically with chest pain, shoulder, or epigastric pain (96% of cases), with or without radiation to the arm (52%), less frequently with nausea or vomiting (24%), radiation to the neck (22%), diaphoresis (21%), dyspnoea (20%) and infrequently with back pain, dizziness, fatigue, headache or syncope (<20% each) [2]. Symptom severity can vary from mild to severe and cardiac dysfunction can cause heart failure, hypotension and dysfunction of other organs.
Diagnosis
Spontaneous coronary artery dissection manifests as an ACS and thus is diagnosed by electrocardiogram (ECG) findings and serial troponins. ECG changes may be absent or subtle (minor ST/T changes), or may show a typical ST-segment elevation MI (STEMI). The ratio of SCAD presentations with STEMI versus non-ST-segment elevation MI (NSTEMI) varies from ∼1:1 to 1:3. The standard test to diagnose SCAD is coronary angiography ± intracoronary nitroglycerin. Diagnostic angiographic features include:
Clinical Management
Conservative medical management is recommended in patients without ongoing chest pain or ECG changes and usually is associated with spontaneous healing of the affected segment on subsequent angiography [18]. Long-term aspirin and β-blockers are commonly prescribed, although the rationale for using anti-platelet or anti-coagulant therapy, including aspirin, in patients with an IMH without an intimal tear, is tenuous, given that such therapy may increase bleeding within the vessel wall.
Outcomes
In-hospital outcomes are generally very good with urgent revascularisation or other major adverse effects being reported only in 5–10% of cases, with in-hospital mortality being <5% [4]. Out-of-hospital mortality is unknown. Post-discharge, major adverse cardiac events (MACE) (including mortality 1.2%, recurrent MI 17%, recurrent SCAD, 10.4% stroke or transient ischaemic attack 1.2%, and revascularisation 6%) have been reported to occur in ∼20% of cases (∼6 MACE events/100 person-years) over a
Pregnancy-Associated SCAD
Two studies involving 120 and 54 cases of pregnancy-associated SCAD (P-SCAD) have been reported [22], [23]. Both are retrospective studies involving data collected from case reports, small case series or a registry. As such, they have the limitations of incomplete data collection, ascertainment bias, or preferential submission and reporting of more complicated cases. Nevertheless, there is good agreement between the findings of the studies. Most cases occurred in the early post-partum period,
Conclusion
Spontaneous coronary artery dissection is an important but under-recognised cause of ACS and a high index of suspicion for this condition should be maintained so appropriate investigations (electrocardiogram (ECG), troponins and coronary angiography) are performed to make the diagnosis. The typical SCAD patient has been well described. In over 90% of cases, the patient is a woman in her early 40s to 50s presenting with symptoms of an ACS, but who has few if any traditional risk factors
Acknowledgements
This paper is dedicated to our brave SCAD patients and their families. Supported in part with grants from the Cardiac Society of Australia and New Zealand generously provided by Boehringher Ingelheim, St. Vincent's Clinic Foundation and from the Catholic Archdiocese of Sydney. We are grateful to our colleagues who are actively engaged with us in research into the pathophysiology of SCAD, including Siiri Iismaa, Claire Wong, Ketan Mishra, Diane Fatkin, Sally Dunwoodie, Richard Harvey, Eleni
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Spontaneous coronary artery dissection
2021, Revista Clinica EspanolaSpontaneous Coronary Artery Dissection and Fibromuscular Dysplasia: Vasculopathies With a Predilection for Women
2021, Heart Lung and CirculationCitation Excerpt :It presents as an ACS (ST elevation myocardial infarct [STEMI], non-STEMI or unstable angina) or sudden death. It is due to a spontaneous bleed into the wall of a coronary artery leading to an intramural haematoma (IMH) [9,10]. The IMH causes the wall of the culprit vessel to bulge into the lumen thereby obstructing blood flow to the myocardium that is perfused by the affected artery (Figure 1).
Generation of VCCRIi001-A, a human induced pluripotent stem cell line, from a patient with spontaneous coronary artery dissection
2019, Stem Cell ResearchCitation Excerpt :To aid in understanding the pathophysiological mechanisms of SCAD, hiPSCs were generated from a SCAD survivor. SCAD is a non-atherosclerotic form of CAD that predominantly affects young to middle-aged women, accounting for 23–36% of acute myocardial infarcts, who have few traditional cardiovascular risk factors, such as obesity, diabetes, dyslipidemia or high blood pressure, and can recur in up to 30% of cases (Graham et al., 2018; Saw et al., 2017). It is likely a systemic vasculopathy, associated not infrequently with other vascular disorders (fibromuscular dysplasia, cervical artery dissection, migraine), but evidence of inflammatory processes is lacking and associated genetic causes of vasculopathy, such as Ehlers Danlos and Loeys-Dietz, are rarely found.
Prevalence of Anxiety, Depression, and Distress in SCAD and Non-SCAD AMI Patients: A Comparative Study
2023, Journal of Cardiopulmonary Rehabilitation and Prevention
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This editorial is based on the invited Kempson Maddox Lecture given by Professor Bob Graham at the Cardiac Society of Australia and New Zealand (CSANZ) Annual Scientific Meeting, Perth, WA, Australia, August 2017.