Echocardiographic Red Flags in Wild-Type Transthyretin Amyloidosis: Sex-Specific Gaps for Wall Thickness and Left Ventricular Mass

<b>Background:</b> Wild-type transthyretin amyloidosis (ATTRwt) diagnosis remains challenging. Echocardiographic "red flags" play a significant role in raising diagnostic suspicion. <b>Methods:</b> Retrospective study including 33 patients diagnosed with ATTRwt. All patients underwent comprehensive echocardiographic evaluation focusing on the red flags for ATTRwt. Left ventricular hypertrophy (LVH) was defined as interventricular septal wall thickness (IVST) ≥ 12 mm and/or LV mass indexed for body surface area (LVMI) ≥ 115 g/m² in men and ≥ 95 g/m² in women. <b>Results:</b> Relative wall thickness > 0.42 and early diastolic myocardial velocity < 7 cm/s were detected in 100% of patients. Severe diastolic dysfunction (grade ≥ 3) (72.7%), apical sparing (36.4%), granular sparkling pattern (30.3%), and pericardial effusion (39.4%) were also observed. Females were younger than males (median age 68 vs. 74.5 years), and IVST ≥ 12 mm was lower in females than in males (64.4% vs. 100%, respectively, <i>p</i> < 0.05). The combined criterion of IVST ≥ 12 mm in men and LVMI ≥ 95 g/m² in women was encountered in 100% of the global cohort. <b>Conclusions:</b> IVST is a good predictor of LVH in males but shows limited sensitivity for ATTRwt in females; a gender-differenced approach (IVST for men and LVMI for women) might better stratify for ATTRwt suspicion.