Impact of statins in patients with vasospastic angina: A multicenter registry study of the Japanese Coronary Spasm Association

Vasospastic angina: Past, present, and future

Vasospastic angina (VSA) is characterized by episodes of rest angina that are responsive to short-acting nitrates and are attributable to coronary artery vasospasm. The condition is underdiagnosed as the provocation test is rarely performed. VSA, the most important component of non-obstructive coronary artery disease, can present with angina, be asymptomatic, or can even present with fatal arrhythmias and cardiac arrest. Although most patients with VSA respond well to vasodilating medications, prognosis does not improve as expected in most patients, suggesting the existence elusive prognostic factors and pathogenesis that warrant further exploration. Moreover, patients with either severe or refractory VSA barely respond to conventional treatment and may develop life-threatening arrhythmias or suffer sudden cardiac death during ischemic attacks, which are associated with immune-inflammatory responses and have been shown to achieve remission following glucocorticoid and immunoglobulin treatments. Our recent work revealed that inflammation plays a key role in the initiation and development of coronary spasms, and that inflammatory cytokines have predictive value for diagnosis. In contrast to the existing literature, this review both summarizes the theoretical and clinical aspects of VSA, and also discusses the relationship between inflammation, especially myocarditis and VSA, in order to provide novel insights into the etiology, diagnosis, and treatment of VSA.

Management of Coronary Artery Spasm

Calcium channel blockers (CCBs) are the first-line treatment for coronary artery spasm (CAS). When CAS-related angina symptoms are not well controlled by CCB therapy, long-acting nitrates or (where available) nicorandil can be added as second-line medications. In the case of CAS refractory to standard treatments, several other alternative drugs and interventions have been proposed, including the Rho-kinase inhibitor fasudil, anti-adrenergic drugs, neural therapies and percutaneous coronary interventions. In patients with syncope or cardiac arrest caused by CAS-related tachyarrhythmias, or even bradyarrhythmias, implantation of an ICD or pacemaker, respectively, should be considered according to the risk of recurrence and efficacy of vasodilator therapy.

Effect of Statins on Major Adverse Cardiovascular Events in Patients with Coronary Artery Spasm: A Meta-Analysis of the Asia Region

Background

Whether statins can reduce major cardiovascular adverse events (MACE) in patients with coronary artery spasm (CAS) is controversial. And most of the relevant research to date has been conducted in Asia.

Methods

We systematically searched electronic databases for studies on the effect of statins on MACE in patients with CAS in Asia and published up to September 2022. We included data on MACE in a statin therapy patient group and a no-statin therapy control group. We then evaluated the effect of statin therapy on MACE in patients with CAS in Asia by meta-analysis and trial sequential analysis (TSA). All statistical analyses were performed using Stata 16.0 software and TSA software.

Results

A total of 10 studies (n = 9333 patients) were included in the final analysis. Meta-analysis showed that the use of statins had a significant effect on MACE in CAS patients (with RR, 0.70; 95% CI, 0.49-0.99), and the sensitivity analysis further confirmed this finding. Subgroup analysis suggested that the correlation between statin therapy and reduced MACE endpoint was stronger in Japanese patients and patients followed up for more than 4 years. But our TSA results indicated that the available samples were insufficient and further research is needed.

Conclusions

Our meta-analysis suggests that statin therapy can reduce MACE in patients with CAS in Asia, and the correlation between the two was stronger in Japanese patients and patients followed up for more than 4 years.

MINOCA: One Size Fits All? Probably Not—A Review of Etiology, Investigation, and Treatment

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous group of conditions that include both atherosclerotic (coronary plaque disruption) and non-atherosclerotic (spontaneous coronary artery dissection, coronary artery spasm, coronary artery embolism, coronary microvascular dysfunction, and supply–demand mismatch) causes resulting in myocardial damage that is not due to obstructive coronary artery disease. Failure to identify the underlying cause may result in inadequate and inappropriate therapy in these patients. The cornerstone of managing MINOCA patients is to identify the underlying mechanism to achieve the target treatment. Intravascular imaging is able to identify different morphologic features of coronary plaques, while cardiac magnetic resonance is the gold standard for detection of myocardial infarction in the setting of MINOCA. In this review, we summarize the relevant clinical issues, contemporary diagnosis, and treatment options of MINOCA.