Table 1

Comparison of characteristics of patients with thin and thick filament variants

Thin filament
(n=21)
Thick filament
(n=130)6 7
P value
Age at diagnosis (median)13.0 (IQR 8.3–14.0)10.6 (IQR 5.0–14.1)0.361
Symptoms at baseline9 (43.9%)51 (39.2%)0.753
Medication at baseline10 (47.6%)48 (36.9%)0.350
Baseline echocardiogram
 LVOT gradient ≥30 mm Hg1 (4.8%)18 (13.8%)0.244
 Median LVOT gradient (mm Hg)6.0 (IQR 5.0–10.0)8.0 (IQR 5.0–14.5)0.257
 MLVWT (median, IQR) at baseline15.0 (IQR 9.5–25.5)15.5 (IQR 11.0–23.)0.864
 MLVWT Z-score (median, IQR) at baseline7.6 (IQR 1.5–16.7)9.6 (IQR 5.3–15.9)0.227
 LA diameter, mm (mean±SD) at baseline28.7±9.332.1±8.00.390
 LA Z-score (mean±SD) at baseline−0.3±3.01.6±2.10.035
Outcomes
 Median age at last follow-up18.0 (IQR 15.0–20.0)15.8 (IQR 11.4–17.4)0.009
 ICD insertion13 (61.9%)50 (38.5%)0.043
 Myectomy1 (4.8%)9 (6.9%)0.712
 OOHCA2 (9.5%)8 (6.2%)0.564
 NSVT on ambulatory ECG6 (28.6%)14 (10.8%)0.026
 MACE3 (14.3%)18 (13.8%)0.957
 Death08 (6.2%)0.243
 Cardiac transplantation05 (3.8%)0.361
  • ICD, implantable cardiac defibrillator; LA, left atrium; LVOT, left ventricular outflow tract; MACE, major adverse cardiac events; MLVWT, maximal left ventricular wall thickness; NSVT, non-sustained ventricular tachycardia; OOHCA, out-of-hospital arrest .