Long-term efficacy of low-density lipoprotein apheresis on coronary heart disease in familial hypercholesterolemia. Hokuriku-FH-LDL-Apheresis Study Group

Intravascular ultrasound evaluation of coronary plaque regression by low density lipoprotein-apheresis in familial hypercholesterolemia: the Low Density Lipoprotein-Apheresis Coronary Morphology and Reserve Trial (LACMART)

OBJECTIVES

We sought to assess the effects of low density lipoprotein (LDL)-apheresis (LDL-A) for regression of coronary plaque in familial hypercholesterolemia (FH), we set up a one-year follow-up multicenter trial using coronary angiography and intravascular ultrasound (IVUS).

BACKGROUND

It is still unclear whether aggressive lipid-lowering therapy by LDL-A leads to the regression of coronary plaque in patients with FH.

METHODS

Eighteen patients with FH were assigned to one of two groups: medication + LDL-A (LDL-A group, n = 11) and medication only (medication group, n = 7). Total cholesterol, triglycerides, high density lipoprotein cholesterol and LDL cholesterol were measured in all subjects at the outset of treatment (baseline) and every three months thereafter. Coronary angiography and IVUS were performed at the outset and after the one-year follow-up period to measure minimal lumen diameter (MLD) by coronary angiogram and plaque area (PA) by IVUS.

RESULTS

The LDL-A group showed 28.4% reduction in total cholesterol (from 275 +/- 27 mg/dl to 197 +/- 19 mg/dl) and 34.3% reduction in LDL cholesterol (from 213 +/- 25 mg/dl to 140 +/- 27 mg/dl) after one-year follow-up, while the medication group showed no changes in cholesterol levels. There were significant interactions between both treatments in total cholesterol (p = 0.0001), LDL cholesterol (p = 0.0001), MLD (p = 0.008) and PA (p = 0.017) using two-way repeated-measures analysis of variance by the SAS system (SAS Institute Inc., Cary, North Carolina). Significant differences were seen in net change in MLD (p = 0.004) and PA (p = 0.008) during the one-year follow-up period between both groups.

CONCLUSIONS

These results suggest that aggressive lipid-lowering therapy using the combination of LDL-A and lipid-lowering drugs may induce regression of coronary atherosclerotic plaque in FH patients.

Single LDL apheresis improves serum remnant-like particle-cholesterol, C-reactive protein, and malondialdehyde-modified-low-density lipoprotein concentrations in Japanese hypercholesterolemic subjects

BACKGROUND

Single low-density lipoprotein (LDL)-apheresis may affect serum remnant-like particle-cholesterol (RLP-C), C-reactive protein (CRP) and malondialdehyde-modified (MDA)-LDL concentrations.

SUBJECTS AND METHODS

Six subjects with hypercholesterolemia (five men, one woman) were involved in this study. Mean age and body mass index of the study subjects were 58+/-3.1 years and 23.6+/-2.07 kg/m(2), respectively. Five of the subjects were diagnosed as heterozygous familial hypercholesterolemia (FH) because of having both marked hypercholesterolemia and Achilles tendon xanthomas. LDL apheresis was introduced and continued using a dextran sulfate cellulose adsorption column technique every 2 weeks. Serum RLP-C was measured using an immunoaffinity mixed gel containing anti-apolipoprotein A-I and anti-apolipoprotein B monoclonal antibody. Serum CRP was measured by latex-enhanced assay. Serum MDA-LDL was measured using monoclonal antibody against MDA-LDL (ML25).

RESULTS

Combined treatment in the steady state pre-treatment yielded a total, LDL- and HDL-cholesterol, and TG concentrations of 5.39+/-0.81, 3.82+/-1.03, 1.24+/-0.29 and 0.92+/-0.43 mmol/l, respectively, and a post-treatment total, LDL- and HDL-cholesterol and TG concentrations of 2.79+/-0.37 (-48%, p<0.001), 1.63+/-0.29 (-57%, p<0.001), 1.18+/-0.26 (-5%, NS) and 0.23+/-0.11 mmol/l (-75%, p<0.001), respectively. Serum RLP-C and CRP concentrations showed a substantial reduction [-73%, p<0.05 for RLP-C; -56%, p<0.05 for CRP] during this procedure. In addition, LDL apheresis was found to also cause a marked reduction in serum MDA-LDL concentration (-61%, p<0.05).

CONCLUSION

LDL-apheresis is an effective treatment for removing atherogenic factors RLP-C, CRP and MDA-LDL from sera.

Comparison of two filter combinations for low-density lipoprotein apheresis by membrane differential filtration: a prospective crossover controlled clinical study

Membrane differential filtration is an accepted procedure for the extracorporeal removal of low-density lipoprotein (LDL). Reduction rates largely depend on the nature of the membranes and are ideally evaluated in a crossover study design. Four patients who had been treated by LDL apheresis for at least 6 months were included. Six consecutive weekly sessions (40 ml plasma/kg body weight) were scheduled per system (Plasmacure PS06/Evaflux Eval 5A [Kuraray] versus Plasmaflo OP05W/Cascadeflo AC1770 [Asahi]). Laboratory measurements indicated reductions of plasma concentrations for fibrinogen (37% [Kuraray] versus 44% [Asahi]), IgG (15% versus 20%), IgA (24% versus 28%), IgM (63% versus 53%), and total protein (11% versus 16%). Total cholesterol was eliminated by 52% versus 49%, LDL by 67% versus 66%, triglycerides by 56% versus 41%, and high-density lipoprotein by 10% versus 20%. Three therapies employing the Asahi filter combination were terminated prematurely due to saturation of the plasma fractionator. In conclusion, despite similar physical properties, the membranes differ significantly concerning selectivity and sensitivity to saturation.

Familial Hypercholesterolemia

Heterozygous familial hypercholesterolemia is a common, severe form of elevated plasma, low-density lipoprotein (LDL) cholesterol. Familial hypercholesterolemia is under-recognized and under-treated despite well-known benefits from available lipid-lowering medications. To help address these problems, the humanitarian MEDPED (Make Early Diagnoses, Prevent Early Deaths) organization was developed as a means to find and help persons with familial hypercholesterolemia all over the world. Although some patients with familial hypercholesterolemia can be treated adequately with a statin alone, many require aggressive treatment with a combination of drugs, including a statin, bile acid sequestrant, and niacin to reach LDL goals. Such treatment has resulted in regression of angiographically monitored coronary lesions in patients with familial hypercholesterolemia.

Beneficial effect of aggressive low-density lipoprotein apheresis in a familial hypercholesterolemic patient with severe diabetic scleredema

We present a 59-year-old woman with severe diabetic scleredema (DS) associated with heterozygous familial hypercholesterolemia (FH). She had been treated with drugs to lower blood glucose, with insulin for diabetes mellitus (DM), and with low-density lipoprotein (LDL) apheresis therapy monthly or every 2 weeks in addition to drugs to lower serum lipids for FH. However, her scleredema had not improved. After we had tried weekly LDL apheresis therapy for a period of 3 years to treat her hyperlipidemia, the levels of her serum lipids were reduced to normal ranges, and scleredema in her nape improved. We also demonstrated the histopathological improvement in dermis of her cervical skin. We conclude that weekly LDL apheresis therapy is effective for diabetic scleredema that is resistant to conventional treatments.

Low-density lipoprotein apheresis for the treatment of refractory hyperlipidemia

The advent of treatment with 3-hydroxy-3-methylglutaryl coenzyme A inhibitors has meant that, with a combination of diet and drug therapy, adequate control of serum cholesterol concentrations can be achieved in most patients with hypercholesterolemia. However, some patients, primarily those with familial hypercholesterolemia (FH), may require additional therapy to lower their cholesterol levels. In recent years, low-density lipoprotein (LDL) apheresis has emerged as an effective method of treatment in these patients. The criteria for commencement of LDL apheresis are LDL cholesterol levels of 500 mg/dL or higher for homozygous FH patients, 300 mg/dL or higher for heterozygous FH patients in whom medical therapy has failed, and 200 mg/dL or higher for heterozygous FH patients with documented coronary disease and in whom medical therapy has failed. In addition to cholesterol lowering in patients with FH, other indications for LDL apheresis are emerging. These include its use in the treatment of graft vascular disease in patients receiving cardiac transplants as well as in the treatment of certain glomerulonephritides. This review examines the role of LDL apheresis in the management of lipid disorders and the evidence available to support its use in clinical practice.

Dyslipidemia

The major goal in treatment of patients with dyslipidemia is to decrease the short- and long-term incidence of cardiovascular events, including myocardial infarction, unstable angina, stroke, and death. A second goal in patients with severe hypertriglyceridemia is to decrease the risk of acute pancreatitis. Improvement of the lipid profile can be achieved through a combination of aggressive lifestyle modification and effective drug therapy. Treatment should be tailored to the individual patient, based on the specific lipid abnormalities, the presence or absence of pre-existing coronary artery or other atherosclerotic vascular disease, and an assessment of overall cardiovascular risk.

Effects of low-density lipoprotein apheresis on coronary and carotid atherosclerosis and diabetic scleredema in patients with severe hypercholesterolemia

Correlations between serum cholesterol levels and progression of coronary and peripheral atherosclerosis have been found in many recent studies. It has also been demonstrated that aggressive cholesterol-lowering therapy with low-density lipoprotein (LDL) apheresis, a method of LDL elimination by extracorporeal circulation, is effective not only for coronary artery disease, but also for systemic circulatory disturbance in severe hypercholesterolemic patients with familial hypercholesterolemia (FH) in particular. We found that LDL apheresis treatment with medical therapy improved coronary atherosclerotic lesions, based on coronary angiography evaluation and histopathological observation, suppressed progression of early carotid atherosclerotic lesions on annual B-mode ultrasonography, and improved diabetic scleredema in FH patients. This effectiveness of LDL apheresis appears to be due to recovery of vascular endothelial function and improvement of blood rheology. For diseases that are possibly due to circulation disturbance and that are intractable with drugs alone. LDL apheresis may be worth trying, particularly for patients complicated by hyperlipemia.

Current topics on low-density lipoprotein apheresis

The prognosis of patients suffering from severe hyperlipidemia, sometimes combined with elevated lipoprotein (a) (Lp[a]) levels, and coronary heart disease (CHD) refractory to diet and lipid-lowering drugs is poor. For such patients, regular treatment with low-density lipoprotein (LDL) apheresis is the therapeutic option. Today, there are four different LDL-apheresis systems available: immunoadsorption, heparin-induced extracorporeal LDL/fibrinogen precipitation, dextran sulfate LDL-adsorption, and LDL-hemoperfusion. Despite substantial progress in diagnostics, drug therapy, and cardiosurgical procedures, atherosclerosis with myocardial infarction, stroke, and peripheral cellular disease still maintains its position at the top of morbidity and mortality statistics in industrialized nations. Established risk factors widely accepted are smoking, arterial hypertension, diabetes mellitus, and central obesity. Furthermore, there is a strong correlation between hyperlipidemia and atherosclerosis. Besides the elimination of other risk factors, in severe hyperlipidemia (HLP) therapeutic strategies should focus on a drastic reduction of serum lipoproteins. Despite maximum conventional therapy with a combination of different kinds of lipid-lowering drugs, however, sometimes the goal of therapy cannot be reached. Mostly, the prognosis of patients suffering from severe HLP, sometimes combined with elevated Lp(a) levels and CHD refractory to diet and lipid-lowering drugs is poor. Hence, in such patients, treatment with LDL-apheresis can be useful. Regarding the different LDL-apheresis systems used, there were no significant differences with respect to the clinical outcome or concerning total cholesterol, LDL, high-density lipoprotein, or triglyceride concentrations. With respect to elevated Lp(a) levels, however, the immunoadsorption method seems to be the most effective. The published data clearly demonstrate that treatment with LDL-apheresis in patients suffering from severe hyperlipidemia refractory to maximum conservative therapy is effective and safe in long-term application.

Apheresis technology for prevention and regression of atherosclerosis

Familial hypercholesterolemia (FH) is a congenital disorder of cholesterol metabolism, which is due to a deficiency in low-density lipoprotein (LDL) receptors. The homozygous form of FH is especially liable to coronary artery disease (CAD) in youth because of the very high LDL-cholesterol levels. It is resistant to drug therapy, and LDL-apheresis is the only practical way of treatment for these patients. Some patients with heterozygous FH also have high LDL-cholesterol levels that cannot be brought down into the optimum range by any combination drug therapy. We have treated or are treating 10 homozygous and 28 heterozygous FH patients in our hospital or in affiliated hospitals expert in blood purification. Among the 10 homozygous patients, 2 died of myocardial infarction. Only one young female patient is still free of symptoms, and the other patients have been suffering from regurgitation through the aortic valve although they have not experienced myocardial infarction. Rapid rebound of LDL-cholesterol after each apheresis treatment limits the period during which LDL-cholesterol is in the optimum range. The use of atorvastatin at a high dose (40 mg/day) was attempted to suppress this rebound. In contrast with good results in receptor-defective-type patients, receptor-negative-type patients did not show a response in LDL-cholesterol levels to the statin therapy although there was a slight increase in high-density lipoprotein (HDL)-cholesterol with a decrease in very-low-density lipoprotein-triglyceride and -cholesterol. Follow-up study of the patients with heterozygous FH revealed that LDL-apheresis was effective in lengthening the life expectancy of the patients with pre-existing CAD, especially those who had received intervention coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA). It was also shown that the use of probucol in combination with LDL-apheresis was effective in reducing coronary events as shown by the necessity of CABG or PTCA. Clinical data on the effect of LDL-apheresis, recently reported from some other institutions in Japan, will also be reviewed.

Low-density lipoprotein apheresis in the treatment of atherosclerosis and other potential uses

This review concerns the clinical impact of low-density lipoprotein (LDL) apheresis for patients with refractory hypercholesterolemia. We examine and provide examples of investigations that have demonstrated the clinical benefits of LDL apheresis. In addition to benefits derived from the stabilization or regression of arterial lesions, we highlight other possible mechanisms related to clinical improvement. We also discuss the potential advantages of lipid apheresis for the treatment of patient populations other than those characterized by severe hypercholesterolemia and premature coronary heart disease.

Incorporation of low-density lipoprotein apheresis into the treatment program of patients with severe hypercholesterolemia

Treatment to low-density lipoprotein (LDL) cholesterol targets has become a focus in the management of patients with coronary heart disease (CHD). Many patients with familial hypercholesterolemia (FH) are unable to reach targets because of drug intolerance or extremely high baseline LDL cholesterol levels. Consequently, LDL apheresis has become a useful modality for the treatment of patients with severe hypercholesterolemia. Commonly used LDL apheresis systems utilize immunoadsorption columns, dextran sulfate cellulose columns, or heparin precipitation. A new and simpler treatment modality is emerging which uses whole blood compatible columns. All systems require systemic anticoagulation, extracorporeal processing of blood, and venous vascular access. Acute LDL lowering is 70% to 80% and time-averaged LDL lowering is 40% to 50%. Lipoprotein(a) is also substantially lowered. Clinical efficacy has been shown in several studies. Mechanisms for clinical improvement in addition to regression of atherosclerotic plaque have been suggested by recent research.

Coronary artery bypass surgery with arterial grafts in familial hypercholesterolemia

OBJECTIVE

Familial hypercholesterolemia is a dominantly inherited disorder caused by mutations at the locus for the low-density lipoprotein receptor and is frequently associated with premature coronary artery disease. This study was performed to determine whether arterial grafting was associated with long-term benefits for patients with familial hypercholesterolemia.

METHODS

During the past 18 years, 101 patients with heterozygous familial hypercholesterolemia underwent primary coronary artery bypass grafting, with one hospital death. Group 1 patients (n = 31) received only saphenous vein grafts. Group 2A patients (n = 47) received one internal thoracic artery graft and supplemental vein grafts, and group 2B patients (n = 23) had multiple arterial grafts. After operation, all patients received diet therapy and intensive cholesterol-lowering drug therapy. Thirteen patients received low-density lipoprotein apheresis.

RESULTS

During a mean follow-up period of 95 months, 8 patients died, 9 underwent reoperation, and 12 received catheter intervention. The overall survival was 82% (95% confidence limits, 65%-97%) at 18 years after operation. The survival in group 2 was higher than that found in group 1 (P =.01). The overall freedom from major cardiac events (myocardial infarction, cardiac death, reoperation, and catheter intervention) was 57% (95% confidence limits, 40%-74%) at 16 years after operation. The freedom from reoperation in group 2 was higher than that found in group 1 (P =.03). There was no difference in the survival or freedom from major cardiac events between groups 2A and 2B.

CONCLUSION

Arterial grafting improved the long-term freedom from reoperation in patients with familial hypercholesterolemia. Additional benefit of multiple arterial grafting could not be identified.

Management of hypercholesterolemia

Benefit from the treatment of hyperlipidemia has now been conclusively documented, and this article has focused on the clinical trial data supporting diet and drug therapy in adult patients with different lipoprotein disorders and discussed therapeutic approaches with a focus on reducing plasma concentrations of LDL cholesterol. National guidelines for the use of hypolipidemic drugs are strongly supported by the clinical trials and have appropriately set lower target concentrations of LDL cholesterol for patients with established atherosclerosis or diabetic patients as compared with patients with more than two cardiovascular risk factors or, the lowest risk group, patients without evidence of atherosclerosis and fewer than two known cardiovascular risk factors. The goals of therapy in patients with established atherosclerosis are to prevent further progression and potentially induce regression, whereas in high-risk patients (e.g., those with heterozygous familial hypercholesterolemia) without evidence of atherosclerosis, the aims of therapy are to reduce LDL cholesterol to a concentration at which subclinical atherosclerosis and xanthomas regress and the patient does not develop premature cardiovascular disease. Evidence-based medicine strongly supports clinical benefit from the treatment of hypercholesterolemia in men and women with and without known coronary artery disease, and the main goal should be ensure that patients who could benefit from lipid-lowering therapy are effectively treated and followed to ensure long-term compliance, efficacy, and safety.

Non-pharmacological lowering of low-density lipoprotein by apheresis and surgical techniques

In the past year, new data have appeared on the long-term benefits of low-density lipoprotein apheresis in severely hypercholesterolemic patients who are refractory to lipid-lowering drug therapy. Such data are critical for clinical decision-making, because they confirm the hypothesis that the dramatic reduction in low-density lipoprotein made possible by this technique produces clear-cut clinical benefits. Because of its efficacy and low incidence of side-effects, apheresis for severe drug-refractory hypercholesterolemia has superseded surgical approaches, such as liver transplantation or ileal bypass.

Therapeutic effects of LDL apheresis in the prevention of atherosclerosis

The efficacy and safety of the therapeutic tool which directly removes LDL particles from circulation (LDL apheresis) has already been established for cholesterol-lowering in patients with refractory hypercholesterolemia, such as homozygous familial hypercholesterolemia. Several angiographic studies have demonstrated that regular LDL apheresis therapy had favorable effects on the progression of coronary atherosclerosis. Recently, two clinical reports described excellent long-term follow-up results for patients with coronary artery disease who had been treated with LDL apheresis using dextran sulfate cellulose columns plus adjunctive cholesterol-lowering drug therapy. In addition, there is increasing evidence that LDL apheresis is effective for the prevention of extra-coronary atherosclerotic disease, and it is also reported to have the potential to improve microvascular disorders. Since the mechanisms of clinical improvement caused by LDL apheresis extend beyond simple and drastic reduction of LDL cholesterol, further investigation based on recent vascular biological evidence is needed.

Effects of intensive lipid lowering by low-density lipoprotein apheresis on regression of coronary atherosclerosis in patients with familial hypercholesterolemia: Japan Low-density Lipoprotein Apheresis Coronary Atherosclerosis Prospective Study (L-CAPS)

Twenty-five heterozygous familial hypercholesterolemic patients treated with LDL-apheresis and drugs and 11 patients treated with drugs underwent follow-up angiography 2.3 years later. One-hundred thirteen lesions were measured by quantitative angiography. Mean LDL-cholesterol levels during the trial were 140 +/- 34 mg/dl in the apheresis group and 170 +/- 58 mg/dl (P < 0.05) in the control group. The mean changes in minimal lumen diameter of lesions were +0.19 +/- 0.30 mm (improved) in the apheresis group (n = 76) and -0.44 +/- 0.40 mm (worsened) in the control group (n = 37) (P < 0.0001). When progression and regression were defined as a change in minimal lumen diameter of +/- 0.67 mm, in the apheresis group, two (8%) patients had progression, 19 (76%) stayed unchanged and four (16%) had regression, but in the control group seven (64%) patients had progression and four (36%) stayed unchanged. The frequency of regression or no change was significantly higher in the apheresis group than in the control group (P < 0.004). Intensive cholesterol lowering therapy with LDL-apheresis and lipid lowering drugs can achieve a substantial decrease in LDL-cholesterol levels to induce regression of coronary lesions in familial hypercholesterolemic patients with advanced coronary artery disease.