Patient profile: Female, 56 yo, arterial hypertension, FH of autoimmune diseases, no history of sudden death.
Medical History:
• At the age of 46: Hospitalized for chest pain. Coronary angiography: negative. Diagnosis: myocardial ischemia with normal coronary arteries.
• 2018: Hospitalized again for angina. ECG showed low voltages, flat T-waves in the inf-lat. leads. Coronary angiography: negative. Biopsy: mild hypertrophy and cytoplasmic vacuolization, minimal increase in interstitial fibrosis, no necrosis or inflammatory infiltrates. Mild nonspecific cardiomyopathy. Viral DNA test positive for HHV-6. Serology: HHV-6 in blood (neg), IgG HHV-6 (pos), IgM (neg). Diagnosis: myocarditis due to HHV-6.
• San Camillo Cardiomyopathy Center:
Echocardiogram: basal ant-lat. hypokinesia, EF 60%. Therapy: Bisoprolol 3.75 mg, Ramipril 5 mg, Ranolazine 1000 mg.
MRI: basal transmural ant-lat. and subepicardial lateral LGE. Oedema and hypokinesia coexists. Subacute myocarditis.
MRI at 1 year: mild left ventricular dilation, EF 60%, meso-subepicardial LGE in the ant-lat and inf mid-basal regions without oedema.
Serial Holter ECGs: frequent polymorphic ventricular ectopics, couplets, and runs.
CPET: normal exercise capacity, pVO2 19.4 (ml/min)/kg (90%).
Genetic testing: VUS in DSC, probably pathogenic, and VUS in ABCC9, PKP2, DSP (2 mutations) with uncertain clinical significance.
• In 2022: Readmitted for angina. Elevated Troponin levels. Coro CT angiography: negative. MRI: EF 45%, akinesia of the apex and apical lat. wall; diffuse LGE and edema. Pericardial effusion. Patient refused biopsy. Discharged after recovery (EF 52%) with the diagnosis of recurrent myocarditis. Empagliflozin added.
• Follow up.
ECG: progression of repolarization abnormalities (TWI in V1-V3 + inf.-lat. leads).
Biopsy: fibroadipose replacement, no necrosis or inflammatory infiltrates. Chronic myocarditis and sequels. Viral tests: negative.
CPET and stress echo: VO2peak 20.7 (ml/kg)/min (88%), normal work capacity. Very rare monomorphic PVCs. EF 50%, preserved contractile reserve.
Conclusions: Diagnosis of left dominant arrhythmogenic cardiomyopathy with a typical pattern for hot phases of myocardial inflammation. The first episode could have been triggered by a viral infection on a predisposing genetic substrate. Nadolol 40 mg x2 was introduced. The possibility of ICD implantation was discussed, and patient refused. A six-month follow-up was planned. Family screening results were negative.