Right Ventricular Strain in Fabry Disease: Prognostic Implications

Introduction: Left ventricular (LV) hypertrophy is the main feature of cardiac involvement in Anderson-Fabry disease (FD), but the right ventricle (RV) is also frequently affected. Previous studies failed to demonstrate an independent association between conventional parameters of RV performance and outcomes in FD. Nevertheless, if RV free wall strain (RV-FWS), assessed by 2D speckle tracking analysis, may provide a better prognostication is currently unknown.

Methods: We retrospectively evaluated the association between RV-FWS and the occurrence of cardiovascular events in a cohort of 56 patients with FD. The study endpoint comprises cardiovascular mortality, severe heart failure symptoms, new-onset atrial fibrillation and major arrhythmias requiring device implantation.

Results: Reduced RV-FWS, defined by values lower than 23%, was found in 25 (45%) patients. During a median follow-up of 47 months, 16 (29%) patients met the study endpoint. A ROC-curve analysis confirmed the threshold of reduced RV-FWS (<23%) as the best cut-off for predicting cardiovascular events, but with a lower power compared to left-sided parameters. On univariable Cox regression analysis, RV-FWS, expressed as continuous variable, was significantly associated with the study endpoint (HR: 0.795, 95% CI: 0.710-0.889, p < 0.001). However, RV-FWS did not retain a significant association with outcomes, after adjustment for LV global longitudinal strain or indexed left atrial volume (p = 0.340 and p = 0.289 respectively).

Conclusions: RV-FWS was not independently associated with the occurrence of cardiovascular events in FD, confirming previous observations that prognosis is mainly driven by the severity of LV cardiomyopathy.