The effect of LDL apheresis on progression of coronary artery disease in patients with familial hypercholesterolemia
This study investigated the effect of extracorporal lipid-lowering therapy by low-density lipoprotein (LDL) apheresis on coronary artery disease in a population characterized by early development and rapid progression of atherosclerosis. We treated 32 patients aged between 15 and 63 years with drug-refractory familial hypercholesterolemia, treated once a week by immuno-specific LDL apheresis for 3 years in a controlled prospective and non-randomized trial; 25 patients (14 females and 11 males) completed the study. Noninvasive data were obtained by physical examination, 12-lead ECG and exercise testing. Invasive cardiological data were obtained by cardiac catheterization according to a standardized protocol in four cardiological centers. Left ventricular ejection fraction was calculated using planimetry. Coronary stenoses were measured quantitatively in 23 defined coronary segments by a panel of four investigators with an electronic digital caliper. In addition, overall coronary atherosclerosis was visually qualified. Final decisions on a classification into one of three groups (regression, no change, progression) of coronary atherosclerosis were based on panel consensus. Six cardiac events occurred throughout the study: percutaneous transluminal coronary angioplasty in one patient, coronary bypass grafting in three and two deaths. Statistical analysis of exercise testing yielded no significant change for maximum power and work capacity during the study period. Hemodynamic data revealed no significant change; mean ejection fraction was calculated as 65.8 ± 15.9% at study entry and 67.0 ± 12.7% at completion. Quantitative measurement of 111 circumscribed coronary stenoses showed a mean stenosis degree of 45 ± 26% at entry cineangio-film and 43 ± 22% at final cineangio-film demonstrating no significant change. Eight localized stenoses showed a regression of more than 10% and 11 stenoses a progression of more than 10%. Panel consensus decision for overall coronary atherosclerosis resulted in regression in no patients, no change in 16, questionable progression in 3, definite progression in 5, and undecided in one. We conclude that specific LDL-apheresis therapy can be used effectively for primary and secondary prevention of coronary artery disease in patients with familial hypercholesterolemia. Its beneficial effect was the prevention of further progression of coronary artery disease in the majority of the study population.