Improvement of hemorheology by DALI apheresis: acute effects on plasma viscosity and erythrocyte aggregation in hypercholesterolemic patients

Physiological role of plasma and its components and the clinical implications of different methods of apheresis: A narrative review

Nowadays, therapeutic plasmapheresis (TP) is accepted as part of the treatment for specific groups of diseases. The availability of different methods, including double filtration and adsorption, increases selectivity for the removal of substances. However, the use of these techniques requires a thorough understanding of the characteristics and components of plasma. By considering pivotal papers from several databases, the aim of this narrative review is to describe the characteristics of plasma related to apheresis techniques. We have tried to cover the clinical implications including physiology, estimation of plasma volume, viscosity, and a description of its components including the size, volume of distribution, and half-lives of the different substances to be removed or maintained depending on the clinical situation and applied apheresis technique. Applying this knowledge will help us to choose the right method and dosage and improve the efficacy of the procedure by preventing or addressing any complications.

HELP-(Heparin-induced Extracorporeal LDL Precipitation)-apheresis in heart recipients with cardiac allograft vasculopathy and concomitant hypercholesterolemia: Influence of long-term treatment on the microcirculation

Hyperlipidemic heart transplant patients who develop cardiac allograft vasculopathy (CAV) benefit from HELP-apheresis (Heparin-induced Extracorporeal LDL Precipitation) which enables drastic lowering of plasma low-density lipoprotein, lipoprotein (a), and fibrinogen. There is evidence that HELP-apheresis also improves microcirculation by an immediate improvement of impaired endothelial-dependent vasodilatation and additive hemorheological effects.Therefore, cutaneous microcirculation was examined before, during, and after the first HELP-apheresis in eight hyperlipidemic cardiac transplant recipients with CAV. To study the long-term effect the intravital microscopy was repeated after three and 12 months of weekly apheresis treatment.In CAV patients the baseline mean erythrocyte velocity was pathologically reduced with 0.13±0.07 mm/s. During the first HELP-apheresis the erythrocyte velocity increased significantly (p = 0.0001) and remained increased until the end of the HELP procedure (p < 0.05). After three months of weekly apheresis treatment a decrease of temporary flow stops in the capillaries with a progressive homogenization (concordance) of the cutaneous microcirculation was observed. After one year of weekly treatment a markedly increase in mean erythrocyte velocity under resting conditions occurred. In addition, a reactive post-ischemic hyperemia could be established for the first time.Even the first single HELP-apheresis resulted in a significant improvement of the cutaneous microcirculation. The long-term treatment of these patients resulted in a marked improvement of the cutaneous microcirculation with the tendency to a normalization of the regulation of the capillary perfusion.

Apolipoprotein(a) is the Product of a Pseudogene: Implications for the Pathophysiology of Lipoprotein(a)

Apolipoprotein(a) [apo(a)] is an apolipoprotein unique to lipoprotein(a) [Lp(a)]. Although it has no known function, Lp(a) is a risk factor for accelerated atherothrombosis. We hypothesize that LPA, the gene which encodes apo(a), is a heretofore unrecognized unprocessed pseudogene created by duplication of PLG, the gene which encodes plasminogen. Unprocessed pseudogenes are genes which were created by duplication of functional genes and subsequently lost function after acquiring various mutations. This hypothesis explains many of the unusual features of Lp(a) and apo(a). Also, this hypothesis has implications for the therapy of elevated Lp(a) and atherothrombosis theory. Because apo(a) is functionless, the diseases associated with elevated levels of Lp(a) are due to its impact on blood viscosity.

LDL-apheresis in Acute Anterior Ischemic Optic Neuropathy

Acute anterior ischemic optic neuropathy (AION) is a disabling disease which impairs visual function. Standard treatment is unable to affect the outcome and the visual damage persists. We describe the case of a 64-year-old patient affected by AION, whose only known risk factor was hypercholesterolemia. After a first onset of involvement of the right eye (RE), the patient presented four weeks later with an analogous episode affecting the left eye (LE). Since standard treatment, started at involvement of the RE, had not yielded any beneficial effect, the patient underwent three sessions of LDL apheresis. The scotomatous portion of the visual field reduced even after the first session, there was further improvement after the third, and after six months the condition remained stable. Corrected vision improved from 2/10 to 6/10 after the third session. LDL cholesterol and fibrinogen decresade after the third session from 239 mg/dL to 31 mg/dL and from 289 mg/dL to 92 mg/dL, respectively. In conclusion, thanks to its effect of antagonizing hemorheologic disorders of the ocular microcirculation, LDL apheresis seems to be an efficacious treatment of AION, especially in patients suffering from hypercholesterolemia.

The effect of flow acceleration on the cyclic variation of blood echogenicity under pulsatile flow

It has been shown that the echogenicity of blood varies during a flow cycle under pulsatile flow both in vitro and in vivo. In general, the echogenicity of flowing whole blood increases during the early systole phase and then reduces to a minimum at late diastole. While it has been postulated that this cyclic variation is associated with the dynamics of erythrocyte aggregation, the mechanisms underlying this increasing echogenicity with flow velocity remain uncertain. The effect of flow acceleration has also been proposed as an explanation for this phenomenon, but no specific experiments have been conducted to test this hypothesis. In addition, the influence of ultrasonic attenuation on the cyclic variation of echogenicity requires clarification. In the present study, a Couette flow system was designed to simulate blood flowing with different acceleration patterns, and the flow velocity, attenuation, and backscattering coefficient were measured synchronously from 20%- and 40%-hematocrit porcine whole blood and erythrocyte suspensions using 35-MHz ultrasound transducers. The results showed ultrasonic attenuation exerted only minor effects on the echogenicity of blood under pulsatile flow conditions. Cyclic variations of echogenicity were clearly observed for whole blood with a hematocrit of 40%, but no variations were apparent for erythrocyte suspensions. The echogenicity did not appear to be enhanced when instantaneous acceleration was applied to flowing blood in any case. These findings show that flow acceleration does not promote erythrocyte aggregation, even when a higher peak velocity is applied to the blood. Comparison of the results obtained with different accelerations revealed that the cyclic variation in echogenicity observed during pulsatile blood flow may be jointly attributable to the effect of shear rate and the distribution of erythrocyte on aggregation.

Suppression of high lipid diet induced by atherosclerosis sarpogrelate

Sarpogrelate (SP), a serotonin (5-HT2A) receptor antagonist, is used as an anti-platelet agent for the treatment of some vascular diseases. SP has been reported to inhibit 5-HT induced coronary artery spasm, increase in intracellular calcium and smooth muscle cells proliferation. This study was undertaken to test that SP suppresses the development of atherosclerosis due to high cholesterol diet (HCD) by decreasing blood viscosity and oxidative stress. For this purpose, 29 rabbits were divided into four groups: control group (normal diet); normal diet group with SP at the dose of 5 mg/kg/day; HCD group fed 1% cholesterol; and HCD group with SP at the dose of 5 mg/kg/day. After 90 days of the experiment, blood samples were collected and the animals were killed; the thoracic aorta was stained by the Oil Red O staining method. The results indicate that plasma levels of cholesterol, triglycerides and malondialdehyde were increased in rabbits fed HCD. Plasma viscosity and whole blood viscosity were also higher in the HCD group than that in normal diet group. Treatment with SP prevented these alterations induced by HCD whereas this agent had no significant effect in rabbits fed normal diet. Morphological examination of the aorta revealed that SP treatment prevented the formation of foam cells and atherosclerotic plaque. It is suggested that the beneficial effects of SP in atherosclerosis may be due to actions on blood viscosity, lipid levels and oxidative stress.

Protein adsorption during LDL-apheresis: proteomic analysis

BACKGROUND

The aim of our study was to investigate the clearance of functional proteins by different low-density lipoprotein-apheresis (LDL-A) methods with the help of proteomic analyses.

METHODS

Proteins were eluated from the different LDL-A columns and investigated with 2D electrophoresis combined with mass spectrometry methods. In parallel, we quantified the plasma protein loss from patients treated with double-filtration plasmapheresis (DFPP; n = 9), direct adsorption of lipoproteins (DALI; n = 5) or heparin-induced extracorporeal LDL precipitation (HELP; n = 7) with routine laboratory methods and western blots.

RESULTS

Proteomic analyses of the column-bound proteins revealed a column-type-dependent loss with the highest number of protein spots in DALI-treated patients (1001 +/- 36), followed by HELP (881 +/- 25) and DFPP (535 +/- 20). More than 70 functional proteins were identified. These proteins are involved in the coagulation pathway (e.g. kininogen1) and have adhesive (e.g. fibronectin), rheological (e.g. fibrinogen) and immunological/inflammatory properties (e.g. complement components). Quantification with western blot analyses demonstrated a significant depletion (P < 0.01) of these proteins comparing serum samples before and after the column with a systemic lowering in patients' serum.

CONCLUSIONS

These data reveal strong interaction between column and serum proteins during LDL-A. The clearance of proteins with adhesive, rheological, and inflammatory characteristics may have beneficial effects on microcirculation and reduce chronic inflammation but may also concomitantly induce side effects such as an increased bleeding risk.

Direct Adsorption of Low-Density Lipoprotein by DALI-LDL-Apheresis: Results of a Prospective Long-term Multicenter Follow-up Covering 12 291 Sessions

Direct adsorption of lipoproteins (DALI) is the first low density lipoprotein (LDL)-apheresis technology by which atherogenic LDL and lipoprotein(a) (Lp(a)) can be selectively removed from whole blood without plasma separation. The present follow-up was carried out to evaluate the clinical efficacy, selectivity and safety of long-term DALI apheresis. The follow-up was carried out in an open, prospective uncontrolled multicenter clinical design. Included were 158 drug-resistant hypercholesterolemic patients from 28 apheresis centers. These patients underwent 12 291 DALI sessions between January 1997 and March 2002. The patients suffered from severe atherosclerosis and their mean LDL-C was 188 mg/dL before the sessions. Mean follow-up was 25 +/- 16 (range 1-56) months during which 78 +/- 53 sessions were carried out. In most treatments, DALI 750 (63%) or DALI 1000 (30%) adsorbers were used. On average, 7423 +/- 1495 mL blood was processed at a flow rate of 84 +/- 16 mL/min in 102 +/- 25 min. Acute reductions by the single DALI sessions averaged 69 +/- 12% for LDL-C, 41 +/- 18% for TG, 15 +/- 10% for HDL-C, 19 +/- 11% for fibrinogen and 62 +/- 24% for Lp(a) (in patients with Lp(a) > 30 mg/dL). Adverse events were recorded in only 3.9% of the sessions. In this 5-year follow-up, long-term therapy with DALI was safe, effective and selective as LDL-C and Lp(a) could be reduced by >60% per session in approximately 100 min treatment time while HDL-C decrease and the incidence of AE were low.

Plasma dependent reduction in red blood cell aggregation after dextran sulfate low-density lipoprotein apheresis--implications for rheological studies

Red blood cell (RBC) aggregation is increased in familial hypercholesterolemia, and is reduced significantly after low density lipoprotein (LDL) apheresis. The purpose of the present study was to clarify whether this reduction depends on changes in plasma composition, RBC membrane properties, or both. RBC aggregation was determined in a computerized cell flow-properties analyzer, before and after LDL apheresis. We compared RBC aggregation in autologous plasma with aggregation in a plasma-free standard solution (0.5% of dextran 500 kDa) to define the separate contributions of plasma and cellular properties to the observed RBC aggregation. RBC aggregation in autologous plasma was reduced by 35.5% after LDL apheresis (P=0.01) but was not significantly affected when measured in dextran 500. This suggests that LDL apheresis attenuated RBC aggregation by altering plasma composition rather than RBC membrane properties. These results are relevant to the understanding of hemorheological changes which follow therapeutic apheresis in hypercholesterolemic patients.

LDL-Apheresis Accelerates the Recovery of Nonarteritic Acute Anterior Ischemic Optic Neuropathy

Nonarteritic acute anterior ischemic optic neuropathy (NAION) is a disabling disease which impairs visual function. It is presumed to result from disturbances of microcirculation in the anterior portion of the optic nerve head due to hemodynamic factors derived from excessive blood viscosity, or restriction of the vasal lumen in hypertensive, hypercholesterolemic, diabetic patients. We aimed to determine whether acute reduction of plasma fibrinogen and serum low-density lipoprotein (LDL) cholesterol is effective for treatment of NAION. We recruited 11 patients (7 females, 4 males) with a mean age of 57.2 +/- 19.6 years. All except one of them presented risk factors for atherosclerosis. The mean values of LDL-cholesterol and fibrinogen before treatment were 144 +/- 32 mg/dL and 341 +/- 80 mg/dL, respectively. All were treated with standard therapy (prednisone, salicylate, pentoxiphyllin) and underwent three sessions of LDL-apheresis (HELP system-B Braun) that can reduce plasma LDL-cholesterol and fibrinogen by more than 50% in a very short time. In all patients we observed a drastic reduction of LDL cholesterol and fibrinogen and a clear improvement in the visual functional data. In fact, mean values of corrected vision increased from 3.7/10 +/- 3/10 to 7.9/10 +/- 2.2/10 (P = 0.002) after the third session, while the scotomatous portion of the visual field regressed after the first session, and in 5 patients further regressed after the third session. This improvement had remained stable after 3 months. Thanks to it's effect of antagonizing hemorheologic disorders of the ocular microcirculation, fibrinogen/LDL-apheresis seems to be an efficacious treatment of NAION.

Clinical applications of long-term LDL-apheresis on and beyond refractory hypercholesterolemia

Premature coronary heart disease (CHD) can result from high LDL cholesterol levels even in the absence of any other risk factors. A striking example is found in children who have the homozygous form of familial hypercholesterolemia (FH) with extremely high levels of LDL-cholesterol, and severe atherosclerosis and CHD often develop during the first decades of life. LDL-apheresis was developed for the treatment of severe type of FH patients who are resistant to lipid-lowering drug therapy. Clinical efficacy and safety of the therapeutic tool which directly removes LDL from circulation have already been established in the treatment for refractory hypercholesterolemia in FH patients. The most recently developed method enables lipoproteins to be adsorbed directly from whole blood, using polyacrylate column. In addition to benefits derived from the stabilization or regression of arterial lesions, we highlight other possible clinical applications of LDL-apheresis. However, most of these clinical benefits came from case reports or retrospective studies. Mechanisms related these clinical improvement remain unclear, and prospective randomized controlled trials should be performed for the new clinical indications of LDL-apheresis.

In face of the increasing efficacy of lipid-lowering therapy, is there still a place for LDL-apheresis?

Based on a large body of evidence, high LDL-cholesterol concentrations in blood is a key factor of coronary heart disease (CHD). Overall, the observational studies show a curvilinear relationship between blood cholesterol level and coronary heart disease risk. Even more relevant are the randomised trials, firmly establishing that within just a few years a cholesterol-lowering therapy confers a dramatic effect on cardiovascular morbidity and mortality. More recent studies indicate that there is a greater risk reduction in those subjects achieving lower low-density lipoprotein cholesterol (LDL-C) levels--i.e. lower is better. While this favours aggressive therapy, it is nevertheless imperative to precise patients selection for every therapy that entails a major commitment for the patient and medical community. Therefore, well-defined criteria for use of LDL-apheresis have yet to be established in the light of the expanding therapeutic armamentarium. Based on the current knowledge of the impact of statin therapy and anticipating that new options will further optimize the management of dyslipidemia in high-risk patients, we propose a reliable assessment of the effects of LDL-apheresis.

State of the Art of Low-density Lipoprotein Apheresis in the Year 2003

Low-density lipoprotein (LDL) apheresis is a last-resort treatment for hypercholesterolemic patients resistant to conservative lipid-lowering therapy. In the extracorporeal circuit, LDL, Lp(a) and coagulation factors are selectively eliminated, while the beneficial proteins like high-density lipoprotein, albumin and immunoglobulins are returned to the patient. Clinical effects of LDL apheresis comprise improvement of symptoms like angina and exercise tolerance, reduction of clinical coronary events like unstable angina, need for angioplasty or bypass operation, myocardial infarction and ultimately coronary mortality. The reduction of atherogenic lipoproteins and of coagulation factors by LDL apheresis (LA) positively influences hemorheology, endothelial function and coronary reserve. In the controlled LAARS, LA significantly improved the electrocardiographic signs of myocardial ischemia in the treadmill test. In angiographically controlled trials such as LARS and L-CAPS, a reduction of progression of coronary lesions was observed; in favorable cases, regression of the stenoses could be documented. In addition, in the LDL apheresis coronary morphology trial, LA decreased the coronary plaque area. The Hokuriku trial documented a 72% decrease of coronary events (MACE) in the LA group vs. controls treated only by statins. In longitudinal studies, the incidence of MACE after regular LA decreased compared with the preapheresis period in the same patients. Apart from coronary heart disease, recent studies indicate a positive effect of LA also on carotid artery stenoses and peripheral vascular disease. Prospective randomized studies showed the beneficial effects of cascade filtration on age-related macular degeneration and of heparin-induced LDL precipitation apheresis on acute inner ear deafness.

Comparative Analysis Between Dextran Sulfate Adsorption and Direct Adsorption of Lipoproteins in their Capability to Reduce Erythrocyte Adhesiveness/Aggregation in the Peripheral Blood

The purpose of this study was to compare the degree of erythrocyte adhesiveness/aggregation (EAA) reduction of two low-density lipoprotein (LDL) apheretic procedures, namely direct adsorption of lipoproteins (DALI) and dextran sulfate adsorption (DSA). A significant (P < 0.001) reduction of EAA was noted in six hypercholesterolemic patients who underwent a total of 40 apheretic sessions and no difference was noted in the degree of EAA reduction by the two techniques. Thus. being a real-time and point-of-care test, the erythrocyte adhesiveness/aggregation test can be applied in relevant situations of acute ischemia, where therapeutic LDL apheresis could improve the hemorheology of individuals with increased concentrations of cholesterol and inflammatory sensitive proteins.

Echogenicity variations from porcine blood I: the "bright collapsing ring" under pulsatile flow

The temporal and radial variations of the echogenicity from porcine blood were investigated using a linear M12L transducer with a GE LOGIQ 700 Expert system. The "bright collapsing ring" (BRCR) phenomenon, a bright echogenic ring converging from the periphery to the center of the tube wall and eventually collapsing during a pulsatile cycle in cross-sectional B-mode images, was observed from porcine blood in a mock flow loop within a 0.95-cm diameter tube under certain flow conditions. The BRCR phenomenon from porcine blood was stronger as the peak speed was increased from 10 to 25 cm/s, and the mean echogenicity and the "black hole" (BLH) phenomenon, a central echo-poor zone surrounded by a bright hyperechoic zone, became weaker. As stroke rate was increased from 20 to 60 beats/min (bpm), both the BRCR and the BLH phenomena became weaker. These two phenomena were observed at three transmitting frequencies (9, 11 and 13 MHz). As hematocrit was increased from 12 to 45%, the BRCR phenomenon became more apparent. The nonlinear behavior of backscatter as a function of hematocrit reaching a maximum at hematocrit of 10 approximately 20% was observed near the tube wall, but it changed at the center of the tube, indicating the importance of hemodynamics on the ultrasonic backscatter from flowing blood. The combined effects of shear rate and acceleration on red blood cell aggregation are suggested as a possible mechanism for these phenomena.

Efficacy and safety of DALI LDL-apheresis at high blood flow rates: A prospective multicenter study

Direct adsorption of lipids (DALI) is the first LDL-apheresis method compatible with whole blood. Usually, the blood flow rate is adjusted at 60-80 ml/min, which results in session times of about 2 hr. The present study was performed to test the safety and efficacy of low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) [Lp(a)] removal by DALI at high blood flow rates in order to reduce treatment time. Thirteen chronic DALI patients in seven centers suffering from hypercholesterolemia (LDL-C 162 +/- 42 mg/dl at baseline) and coronary artery disease were treated on a weekly or biweekly basis by DALI apheresis. The blood flow rate QB was held constant for at least two sessions, respectively, and was increased from 60 to 80, 120, 160, 200, and 240 ml/min. All patients had pre-existing av-fistulas. The anticoagulation was performed by a heparin bolus plus ACD-A at a ratio of citrate:blood ranging from 1:20 to 1:90. Clinically, the sessions were well tolerated and only 26/201 sessions (12%) of the treatments were fraught with minor adverse events. Acute LDL-C reductions (derived from LDL-C levels determined by lipoprotein electrophoresis) averaged 72/66/60/53/50/48% for QB=60/80/120/160/200/240 ml/min. Lp(a) reductions were 68/67/62/60/58/56%, whereas HDL-C losses were < or =10%. Routine blood chemistries and blood cell counts remained in the normal range. Treatment times averaged 142/83/45 min at Qb=60/120/240 ml/min. On average, DALI LDL-apheresis could be performed safely and effectively at high blood flow rates up to at least 120 ml/min in patients with good blood access, which significantly reduced treatment time from 142 to 83 min (-42%).

Direct adsorption of low-density lipoprotein and lipoprotein(a) from whole blood: results of the first clinical long-term multicenter study using DALI apheresis

Direct adsorption of lipoproteins (DALI) is the first low-density lipoprotein (LDL)-apheresis technique by which atherogenic LDL and lipoprotein(a) (Lp(a)) can be selectively removed from whole blood without plasma separation. The present study was performed to evaluate the efficacy, selectivity and safety of long-term DALI apheresis. Sixty-three hypercholesterolemic coronary patients were treated by weekly DALI sessions. Initial LDL-cholesterol (C) plasma levels averaged 238 +/- 87 mg/dl (range 130-681 mg/dl). On average, 34 sessions (1-45) were performed processing 1.5 patient blood volumes. The primary aim was to acutely reduce LDL-C by >or=60% per session. To this end, three different adsorber sizes could be employed, i.e., DALI 500, 750, and 1000, which were used in 4, 73, and 23% of the 2156 sessions, respectively. On average, 7387 ml of blood were processed in 116 min per session. This resulted in the following mean acute changes: LDL-C 198 --> 63 mg/dl (-69%), Lp(a) 86 --> 32 mg/dl (-64%), triglycerides 185 --> 136 mg/dl (-27%). HDL-C (-11%) and fibrinogen (-15%) were not significantly influenced. The mean long-term reduction of LDL-C was 42% compared to baseline while HDL-C slightly increased in the long run (+4%). The selectivity of LDL removal was good as recoveries of albumin, immunoglobulins, and other proteins exceeded 85%. Ninety-five percent of 2156 sessions were completely uneventful. The most frequent adverse effects were hypotension (1.2% of sessions) and paresthesia (1.1%), which were probably due to citrate anticoagulation. Access problems had to be overcome in 1.5%, adsorber and hardware problems in 0.5% of the sessions. In this multicenter long-term study, DALI apheresis proved to be an efficient, safe, and easy procedure for extracorporeal LDL and Lp(a) elimination.

Clinical effects of direct adsorption of lipoprotein apheresis: beyond cholesterol reduction

Direct adsorption of lipoproteins (DALI) from whole blood is the first LDL hemoperfusion technique for extracorporeal LDL and Lp(a) elimination without initial plasma separation. Thus, this technique is characterized by high user-friendliness. In a long-term multicenter study, LDL and lipoprotein (a) (Lp(a)) reductions were 69% and 64%, respectively, per session. Adverse effects were rare, as 95% of the sessions were uneventful. Biocompatibility studies showed only minor blood-adsorber interactions for most parameters; however, there was a significant bradykinin generation. After a single session, significant reductions of plasma viscosity, erythrocyte aggregation and adhesion molecules were documented. A retrospective analysis of 18 chronic DALI patients revealed that in the majority of patients, symptoms like angina and dyspnea as well as their general status and subjective well-being improved significantly. Moreover, the objective cardiovascular event rate (MACE) decreased from a total of 26 in the 3-year period prior to DALI to 6 during a mean follow-up of 3.8 years during chronic DALI therapy. Thus, the average event rate of 0.48 per patient year at baseline could be significantly reduced to 0.09 (P < 0.004) by DALI. This impressive improvement of symptoms and coronary events can hypothetically be related to the improvement of hemorheology and the transformation of unstable into stable plaques by DALI LDL apheresis.

Modified DALI LDL-apheresis using trisodium citrate anticoagulation plus bicarbonate or lactate-buffered hemofiltration substitution fluids as primers

BACKGROUND

DALI (direct adsorption of lipids) is the first LDL-apheresis technique able to adsorb low-density lipoprotein (LDL) and lipoproteina) directly from whole blood. In the standard procedure, acid citrate dextrose (ACD-A) is used as anticoagulation and the adsorber is rinsed with a specially manufactured priming solution (PS). Using neutral trisodium citrate (TSC) instead of ACD-A might improve the acid-base homeostasis during DALI apheresis; moreover, applying wholesale hemofiltration solutions instead of the special PS might avoid the use of two separate solutions for both priming before and reinfusion after the treatment, thus simplifiying the procedure.

AIM

The present study was performed to test the effect of neutral (TSC) anticoagulation and of two different commercially available hemofiltration (HF) priming solutions on the efficacy and biocompatibility of DALI apheresis.

MATERIALS AND METHODS

Five hypercholesterolemic chronic DALI patients were treated prospectively, on a weekly or biweekly basis, 3 times each by standard DALI-apheresis (A). by DALI using 4% TSC and bicarbonate-buffered HF BIC35-210 priming (B). as well as by DALI using 4% TSC and lactate-buffered HF 23 priming (C). After the sessions, the extracorporeal circuit (ECC) was rinsed with saline in study arm A and with the corresponding HF solutions in study arms B and C, respectively.

RESULTS

Acute LDL-cholesterol reductions in the study arms A/B/C averaged 64/64/63%, for Lp(a) 62/64/62%, respectively (n=15). Clinically, all sessions were essentially uneventful and no clots were observed in the ECC. No major differences were found between the 3 study arms with respect to biocompatibility (elastase, C3a, thrombin-antithrombin, beta-thromboglobulin, bradykinin).

CONCLUSION

DALI apheresis using TSC anticoagulation and HF solutions for both priming and reinfusion proved to be as safe and effective as the standard DALI apheresis. These modifications, however, further simplify the procedure.