Heart Failure -> Heart Failure Management: -> Monitoring D-PO05 - Poster Session V (ID 39) Poster

D-PO05-121 - Distinct Electrocardiogram Findings Of Cardiac Amyloidosis By Major Amyloid Type (ID 613)


Background: Cardiac amyloidosis is an increasingly recognized cause of heart failure. This infiltrative cardiomyopathy results from primarily transthyretin or light chain amyloid deposition. Early diagnosis is critical for initiation of life prolonging therapies. With higher rates of diagnosis, no recent study has evaluated electrocardiogram (ECG) findings by types of cardiac amyloid.
Objective: To determine ECG differences between cardiac amyloidosis due to light chain amyloid (AL), wild-type transthyretin amyloid (ATTRwt) and mutant transthyretin amyloid (ATTRm).
Methods: We identified 111 patients with cardiac amyloidosis (median age 74; 35% female). Diagnosis was confirmed by cardiac biopsy with mass spectroscopy or technetium pyrophosphate scan to determine if ATTR with genetic testing to assess for familial ATTR. ECG changes were assessed for cardiac amyloidosis patients with ATTRwt (n=18), ATTRm (n=31, primarily p.Val142Ile), and AL (n=51). Patients with paced rhythms were excluded (n=10). Categorical variables were compared using the Chi-Square test or Fisher’s exact test. Continuous variables were analyzed with the Kruskal-Wallis test.
Results: Patients with ATTRwt had significantly longer PR intervals (232.0 ms) and QRS intervals (122.0 ms) compared to ATTRm (PR = 166 ms; QRS = 90 ms) and AL (PR = 164; QRS = 92 ms), p=0.001. Low voltage on limb leads was seen in 39% ATTRwt, 65% ATTRm, and 65% AL. Q-waves and pseudo-infarction patterns were seen more often in ATTRwt (Q-wave: 50% ATTRwt, 32% ATTRm, 18% AL; pseudo-infarction 72% ATTRwt, 45% ATTRm, and 47% AL). ECG criteria for left ventricular hypertrophy was only met in one patient with AL cardiac amyloidosis. Atrial fibrillation was more frequently observed in ATTRwt (50%) compared to ATTRm (16%) and AL (5%), p<0.001.
Conclusion: ECG patterns in cardiac amyloidosis varied by amyloid type. The classical amyloid ECG finding of low voltage in limb leads was seen in most ATTRm and AL patients. However, the majority of patients with ATTRwt had normal voltage, prolonged PR interval, wider QRS, Q-waves and pseudo-infarction pattern. Knowledge of these ECG patterns can aid in early detection of cardiac amyloidosis.