Inclusion Criteria:  Patients indicated to MH center for MH diagnostic  Exclusion Criteria:  conditions clearly not related to MH, e.g. neuromuscular diseases syndromes without MH risk; anaesthetic complications without MH symptoms, e.g. prolongated awakening due to deficit of cholinesterase probands with missing data probands with yet not closed MH diagnostic process (waiting for genetics or IVCT, myopatic patients without MH diagnostic variant where the IVCT was not recommended because of its invasivity) non-compliant probands, who refused the diagnostic process.