Spontaneous coronary artery dissection: A review of medical management approaches.

Spontaneous coronary artery dissection (SCAD) is an underdiagnosed cause of acute coronary syndrome (ACS) that usually presents in young female patients. Risk factors include female sex, physical and emotional stressors, and fibromuscular dysplasia, and diagnosis is usually made by coronary angiography aided by intravascular ultrasound (IVUS) or optical coherence tomography (OCT). While conservative treatment is usually preferred over percutaneous coronary intervention or surgery, medical management of SCAD has been under debate. This comprehensive review aims to summarize findings from recent studies exploring various medical treatment approaches for the management of SCAD. Antiplatelet therapy with aspirin is generally safe and beneficial for SCAD patients, with dual antiplatelet (DAPT) being recommended for patients undergoing PCI. In the absence of intervention, DAPT may be given for a short period followed by a longer single-antiplatelet (SAPT) therapy with aspirin. Beta-blockers appear to be safe and effective for SCAD patients. On the other hand, fibrinolytics, anticoagulants, and glycoprotein IIa/IIIb inhibitors are contraindicated. Cardiovascular medications such as renin-angiotensin-aldosterone system (RAAS) inhibitors, mineralocorticoid receptor antagonists, and statins are not recommended in the absence of left ventricular dysfunction. Hormonal therapy is contraindicated for patients who develop SCAD during pregnancy and future pregnancy is discouraged in that patient population.

Patient-specific computational simulation of coronary artery bypass grafting.

INTRODUCTION: Coronary artery bypass graft surgery (CABG) is an intervention in patients with extensive obstructive coronary artery disease diagnosed with invasive coronary angiography. Here we present and test a novel application of non-invasive computational assessment of coronary hemodynamics before and after bypass grafting. METHODS AND RESULTS: We tested the computational CABG platform in n = 2 post-CABG patients. The computationally calculated fractional flow reserve showed high agreement with the angiography-based fractional flow reserve. Furthermore, we performed multiscale computational fluid dynamics simulations of pre- and post-CABG under simulated resting and hyperemic conditions in n = 2 patient-specific anatomies 3D reconstructed from coronary computed tomography angiography. We computationally created different degrees of stenosis in the left anterior descending artery, and we showed that increasing severity of native artery stenosis resulted in augmented flow through the graft and improvement of resting and hyperemic flow in the distal part of the grafted native artery. CONCLUSIONS: We presented a comprehensive patient-specific computational platform that can simulate the hemodynamic conditions before and after CABG and faithfully reproduce the hemodynamic effects of bypass grafting on the native coronary artery flow. Further clinical studies are warranted to validate this preliminary data.