Spontaneous coronary artery dissection as a cause of myocardial infarction

Spontaneous coronary artery dissection in patients with prior psychophysical stress: a systematic review of case reports and case series

BACKGROUND

Spontaneous coronary artery dissection (SCAD) is an underdiagnosed cause of acute coronary syndrome, particularly in younger women. Due to limited information about SCAD, case reports and case series can provide valuable insights into its features and management. This study aimed to comprehensively evaluate the features of SCAD patients who experienced psychophysical stress before the SCAD event.

METHODS

We conducted an electronic search of PubMed, Scopus, and Web of Science from inception until January 7, 2023. We included case reports or series that described patients with SCAD who had experienced psychophysical stress before SCAD. Patients with pregnancy-associated SCAD were excluded from our analysis.

RESULTS

In total, we included 93 case reports or series describing 105 patients with SCAD. The average patient age was 44.29 ± 13.05 years and a total of 44 (41.9%) of patients were male. Among the included SCAD patients the most prevalent comorbidities were fibromuscular dysplasia (FMD) and hypertension with the prevalence of 36.4 and 21.9%, respectively. Preceding physical stress was more frequently reported in men than in women; 38 out of 44 (86.4%) men reported physical stress, while 36 out of 61 (59.1%) females reported physical stress (p value = 0.009). On the other hand, the opposite was true for emotional stress (men: 6 (13.6%)), women: 29 (47.6%), p value < 0.001). Coronary angiography was the main diagnostic tool. The most frequently involved artery was the left anterior descending (LAD) (62.9%). In our study, recurrence of SCAD due to either the progression of a previous lesion or new SCAD in another coronary location occurred more frequently in those treated conservatively, however the observed difference was not statistically significant (p value = 0.138).

CONCLUSION

While physical stress seems to precede SCAD in most cases, emotional stress is implicated in females more than males.

Spontaneous coronary artery dissection and associated myocardial bridging: Current evidence from cohort study and case reports

Spontaneous coronary artery dissection (SCAD) is a relatively uncommon and under-diagnosed disease characterized by the dissociation of intima and media of coronary artery wall due to an intimal tear or intramural hemorrhage. The exact pathophysiology of SCAD remains elusive and may involve multiple predisposing or precipitating factors including genetic abnormalities, inherited or acquired vasculopathies, hormonal influences, inflammation, intense exercise, emotional stress, and recreational drugs. Accruing reports, including five case reports and one cohort study, have recently addressed the concurrence of SCAD and myocardial bridging (MB), an anatomic variant in which a segment of the epicardial coronary descends and traverses in the myocardium. Among the patients with coexisting MB and SCAD, the left anterior descending artery was the only artery that harbors both pathologies, with SCAD locating either within the tunneled segment or distal to the MB. No other predisposing factors or precipitating stressors for SCAD were noted. It is hypothesized that the predilection for vasospasm, impaired endothelial function, and disturbed coronary flow dynamics associated with MB bridging could collectively contribute to the development of SCAD. Future studies are warranted to explore the mechanistic implications of MB in patients with SCAD.

Role of risk stratification and genetics in sudden cardiac death

Sudden cardiac death (SCD) is a major public health issue due to its increasing incidence in the general population and the difficulty in identifying high-risk individuals. Nearly 300 000 - 350 000 patients in the United States and 4-5 million patients in the world die annually from SCD. Coronary artery disease and advanced heart failure are the main etiology for SCD. Ischemia of any cause precipitates lethal arrhythmias, and ventricular tachycardia and ventricular fibrillation are the most common lethal arrhythmias precipitating SCD. Pulseless electrical activity, bradyarrhythmia, and electromechanical dissociation also result in SCD. Most SCDs occur outside of the hospital setting, so it is difficult to estimate the public burden, which results in overestimating the incidence of SCD. The insufficiency and limited predictive value of various indicators and criteria for SCD result in the increasing incidence. As a result, there is a need to develop better risk stratification criteria and find modifiable variables to decrease the incidence. Primary and secondary prevention and treatment of SCD need further research. This critical review is focused on the etiology, risk factors, prognostic factors, and importance of risk stratification of SCD.