The prognosis of patients with left ventricular hypertrabeculation/noncompaction (LVHT) and its association with neuromuscular disorders (NMDs) is a controversial topic. The aim of this study was to assess whether the prognosis of LVHT patients is dependent on cardiac phenotype and the presence of NMDs. Consecutive patients who were diagnosed with LVHT between 1995 and 2016 were included in the study. Cardiac phenotype was classified according to the recommendations of the European Society of Cardiology as: "dilated" if the left ventricular end-diastolic diameter (LVEDD) was >57 mm and left ventricular fractional shortening (FS) was ≤25%; "hypertrophic" if LVEDD was ≤57 mm, FS > 25%, and left ventricular posterior wall (LVPWT) and interventricular septal thickness (IVST) were both >13 mm; "intermediate" if LVEDD was >57 mm and FS > 25% or if LVEDD was ≤57 mm and FS ≤ 25%; and "normal" if LVEDD was ≤57 mm, FS > 25%, and IVST and LVPWT ≤ 13 mm. Therapy was carried out by the treating physicians. LVHT was diagnosed in 273 patients (80 females, 53 ± 16 years). The phenotype was assessed as dilated in 46%, hypertrophic in 8%, intermediate in 17%, and normal in 29% of the patients. Of these patients, 72% underwent neurological examinations, and an NMD was found in 76%. Over a period of 7.4 years (±5.7), 84 patients died and six underwent cardiac transplantation. The highest mortality rate was observed in the dilated and the lowest in the hypertrophic cardiac phenotype groups. Among the dilated phenotype, mortality was higher in patients with than without NMDs. Patients with LVHT and dilated cardiac phenotype have a worse prognosis than patients with a hypertrophic or intermediate/normal cardiac phenotype, especially if they suffer from NMDs.