MINOCA: CMR Was Right.

Description of Clinical Presentation: A 49-year-old male, smoker, with chronic kidney disease secondary to mesangial proliferative glomerulonephritis and psoriasis, but no prior cardiovascular history, presented with oppressive, angina-like chest pain radiating to the neck for two hours. ECG showed preserved R wave progression with ST-segment rectification in V2–V3. Laboratory tests confirmed chronic kidney disease (creatinine 1.47 mg/dl, clearance 55 ml/min), elevated high-sensitivity troponin T (72 pg/ml), and NT-proBNP (855 pg/ml). Echocardiography demonstrated new mild LV systolic dysfunction (LVEF 45%) with anterior and apicoseptal hypokinesia. NSTEMI was diagnosed and treated with aspirin, enoxaparin, and high-dose statins. Coronary angiography showed no significant stenosis.Troponin rose (peak 1549 pg/ml) and also NT-proBNP (3590 pg/ml) with T-wave inversion in anterior leads. Considering the elevated NT-proBNP, the presence of regional wall motion abnormalities, and diffuse T-wave inversions on ECG, an atypical Takotsubo syndrome was considered as a differential diagnosis.
CMR was performed and revealed regional wall motion abnormalities in the anterior/apicoseptal segments, mildly reduced LVEF (49%), elevated T1/T2 mapping, and subendocardial LGE in the LAD territory, consistent with acute myocardial infarction and MINOCA was confirmed.

Four days later, recurrent chest pain with new ST elevation in V1–V3 and troponin rise (55 to 1429 pg/ml) prompted repeat angiography, which revealed a focal, eccentric proximal LAD lesion without significant stenosis. IVUS showed mild ostial LAD plaque without thrombus or dissection. OCT identified a short flap and entry tear consistent with coronary plaque microdissection. PCI with drug-eluting stent implantation was performed with optimal OCT result.

The patient had a favorable outcome with improved LVEF (59%) on follow-up echocardiography and remains asymptomatic in NYHA class I.

Diagnostic Techniques and Their Most Important Findings: CMR revealed mildly reduced LV function (LVEF 49%) with anterior and apicoseptal wall motion abnormalities, elevated T1/T2 mapping indicating edema, and subendocardial LGE in the LAD territory, consistent with acute myocardial infarction. Initial angiography showed no significant stenosis. During recurrent chest pain with ST elevation, repeat angiography revealed a focal eccentric proximal LAD lesion without significant narrowing. IVUS demonstrated mild eccentric plaque (MLA 6.9 mm²) without thrombus or dissection. OCT identified a short flap and entry tear (< 1 mm) at the LAD ostium, compatible with coronary plaque microdissection, causing focal stenosis. PCI with drug-eluting stent implantation was performed with optimal OCT-confirmed result.

Learning Points from this Case: CMR is essential in MINOCA for accurate diagnosis and management. Coronary plaque microdissection may appear non-significant on angiography, requiring intracoronary imaging. OCT can reveal small entry tears or flaps undetected by angiography or IVUS, enabling precise diagnosis and tailored intervention.

A: ECG at 24-hour follow-up showed T-wave inversion in anterior leads, B y C:Coronary angiography showed no obstructive coronary lesions
A: SSFP sequence, 3 chamber view showed anterior septal hypokinesia. B and C: elevated T1 and T2 mapping values consistent with edema. D: LGE in the apicoseptal segment, findings compatible with acute myocardial infarction in the LAD territory
A: IVUS demonstrated mild eccentric plaque (MLA 6.9 mm²) without thrombus or dissection, B: OCT identified a short flap and entry tear ( <1 mm) at the LAD ostium, compatible with coronary plaque microdissection, causing focal stenosis, C,D: PCI with drug-eluting stent implantation was performed with optimal OCT-confirmed result.