Case description: After his morning run a 35 year-old man experienced crushing, retrosternal chest pain radiating to the neck and nausea with no resolution of symptoms at rest. The preclinical ECG and the ECG on arrival showed dynamic changes with initially high, hyperacute T waves and other changes consistent with a “De Winter sign” (Fig.1).
Diagnosis and Treatment: Emergency coronary angiogram was performed via 6F radial access. It revealed a thrombotic, proximal occlusion of the LAD. TIMI II flow was restored after guidewire passage within 60 min after arrival (Fig.2).
| A: occluded LAD (*). B: After wire passage restored TIMI II flow. C: Final result |
Considering the clinical presentation, patient’s age and absence of atherosclerosis, a spontaneous coronary artery dissection (SCAD) or thromboembolic occlusion seemed a possibility. With an aspiration catheter red thrombus was removed from the vessel (Fig.3).
IVUS showed a short dissection and soft, fibrous plaque (Fig.4).
| IVUS images of LAD A: Small dissection entry (*) B: circular plaque as reason for the angiographic tightening C: “Virtual Histology" green depicting fibrous plaque |
Direct stenting with a 3,5/24 mm and a 4,0/14 mm stent was performed with restoration of TIMI III flow and the final result checked with IVUS. The patient remained on the coronary care unit for 72 h. Intravenous heparin was continued for 48 h as residual intravascular thrombus was suspected.
The lipid profile showed an elevated LDL of 104 mg/dl and Lp(a) of 85 mg/dl. The echocardiogram revealed a low-normal LV - EF due to apical, anterior and anteroseptal hypokinesia. Strain analysis found a decreased global longitudinal strain in these areas (Fig.5).
Discussion: In general, bias due to young age might lead to delayed diagnosis of STEMI in this age group. Pathology of MI might be different in this population and differential diagnosis should include plaque rupture, thromboembolic MI and SCAD. SCAD is currently an underdiagnosed mechanism and in women < 50 years probably even a main reason for MI. Nevertheless, as demonstrated in this case, MI due to arteriosclerosis is also possible as some risk factors might be unknown before the event. Intravascular imaging with either OCT or IVUS is necessary to confirm the underlying pathomechanism. With IVUS, fibrous plaque burden and a small dissection in an otherwise healthy vessel were perfectly visualised so that SCAD or a thromboembolic event could be excluded. The differentiation between these pathologies is important for the optimal interventional strategy.
Conclusions: Chest pain should always prompt an ECG to exclude STEMI even in patients of an atypical age group. Recognition of different ECG patterns associated with acute coronary occlusions can be helpful to shorten delay to treatment. Also, intravascular imaging is a necessity for identification of underlying cause of MI and can influence treatment decisions. Post MI care needs to include search for modifiable risk factors and echocardiographic assessment of myocardial damage.
https://dgk.org/kongress_programme/ht2021/P328.htm