Progressive electrocardiographic changes in parallel with cardiac magnetic resonance findings in fabry disease

Background: Cardiac Magnetic Resonance (CMR) allows to detect pro- gressive stages of cardiac involvement in Fabry Disease (FD). A system- atic description of electrocardiographic (ECG) alterations occurring in FD is currently missing. Purpose: To explore ECG changes in progressive stages of FD cardiomy- opathy. Methods: 71 FD patients and 17 healthy controls underwent CMR with T1 mapping and 12-lead ECG. ECG analysis included the duration of the P-wave and the interval between the end of P-wave and the beginning of QRS (PendQ). FD patients in the test cohort were divided into 3 groups with increasing severity of cardiac involvement: A) normal T1, no LVH; B) low T1, no LVH; C) low T1, LVH. Results: An increase of Pwave/PendQ ratio was observed in Group A compared to Controls (1.08 vs. 0.75, p<0.0001). Higher Pwave/PendQratio (1.50 vs. 1.08, p<0.0001), shorter PQc interval (127.9 vs. 159.5, p=0.0007), increased Sokolow-Lyon Index (SLI) (3.2 vs. 2.4, p<0,001) and T wave amplitude (0.6 vs. 0.4 mV, p=0.002) characterized Group B in comparison with Group A. A higher prevalence of left bundle branch blocks (13.6% vs. 0%, p=0.03) and repolarization abnormalities (77.3% vs. 5.7%), wider QRS (120 vs 95 msec, p<0.0001) and QT (460 vs 400 msec, p=0.003) intervals were found in Group C compared to Group B. SLI (AUC 0.769), Pwave/PendQ (AUC 0.778), QRS (AUC 0.703) and QT (AUC 0.769) durations resulted to be independent predictors of low T1 val- ues on CMR at stepwise multivariate analysis. Conclusion: FD is characterized by progressive ECG changes. The iden- tification of ECG parameters able to predict a lowering of myocardial T1 values on CMR may promote early detection of cardiac involvement, help- ing to target the therapeutic approach