Lipoprotein apheresis affects ventricular repolarization in patients with homozygous familial hypercholesterolemia

Aim: Patients with Homozygous Familial Hypercholesterolemia (HoFH) prone to experience premature cardiovascular disease and often die from sudden cardiac death (SCD) at a young age. Lipoprotein apheresis (LA) is the treatment of choice to prolong survival. Several mechanisms has been suggested to be responsible for the known short and long-term clinical benefits of this procedure. This study was conducted to assess the effect of single LA on ventricular repolarization parameters in patients with HoFH.Material and Methods: Eleven patients (mean age 30.1 ± 5.5 years, male 63.6%) with HoFH on chronic LA treatment were enrolled in this preliminary study. Double filtration plasmapheresis (DFPP) was performed in all patients. To examine the effects of a single session of LA, on ventricular repolarization, the OT, QTc interval, the T peak-to-end (Tp-e) interval, Tp-e/QT and the Tp-e/QTc ratio were specifically calculated.Results: The single session of LA reduced total LDL (from 10.04 ± 1.91 to 4.16 ± 1.21 mmol/L, P<001). The heart rate did not change significantly after LA session. Plasma levels of calcium and magnesium was significantly decreased after the procedure. The QTc decreased from 443.8 ± 23.3 ms to 412.3 ± 20.0 ms (P <0.001). The Tp-e interval and the Tp-e/QTc ratio decreased significantly [85 (70-89) ms vs. 63 (58-71)ms; P =0.003, and 0.19 (0.16-0.20) vs 0.15 (0.13-0.16); P =0.003, respectively]. Conclusion: Our data suggest that even a single session of LA improved electrocardiographic repolarization indexes.