LDL apheresis improves coronary flow reserve on the left anterior descending artery in patients with familial hypercholesterolemia and chronic ischemic heart disease.

BACKGROUND: LDL apheresis (LA) influences the microcirculation, endothelial function and cardiovascular homeostasis. The aim of our study was to analyze temporal variations of coronary flow reserve (CFR) on the left anterior descending artery, obtained during dipyridamole stress echocardiography (DSE), in patients with severe familial hypercholesterolemia on LA (LA group) or not (not LA group) and ischemic heart disease (IHD).

METHODS: The LA group consisted in 10 patients (mean age 65 ± 7 years, male 70%) with Familial Hypercholesterolemia and chronic IHD on maximally tolerated lipid lowering therapy and chronic LA treatment (median 7 years, interquartile range 6-14 years). Hyperlipoproteinemia (a) was also present in 6/10 subjects. LA was performed biweekly by dextran-sulfate or heparin-induced LDL precipitation technique. IHD was diagnosed at a mean age of 44 ± 8 years. The control group was matched for age, sex and follow-up period. CFR was calculated as the ratio between blood diastolic velocity sampled at peak stress with dipyridamole and baseline diastolic velocity (normal value > 2.0). No relevant comorbidities were present.

RESULTS: During a median follow-up of 27 months (interquartile range 23-50 months), a significant increase in CFR (from 1.86 ± 0.47 to 2.25 ± 0.35; p < 0.001) was observed in LA group. During this period, no patients modified their anti-ischemic therapy and no cardiovascular events were reported. In the control group, during the study time (24 months - interquartile range 14-57 months) no significant variation in CFR was observed (from 2.08 ± 0.39 to 1.92 ± 0.26; p 0.283).

CONCLUSION: Myocardial blood perfusion, measured as CFR by dipyridamole stress echocardiography-is increased in patients with severe familial hypercholesterolemia chronically treated with LA. DSE might be a reliable tool to monitor the therapeutic effect of lipid lowering therapy.