Trapidil decreases the aggregation of platelets from heart transplant recipients ex vivo.

Heart transplant recipients show platelet hyperaggregability, which may be related to the incidence of graft vasculopathy. We investigated whether trapidil can inhibit the aggregation of platelets from these patients. Platelet count, mean platelet volume (MPV), and adenosine diphosphate (ADP)-induced platelet aggregation were determined in 18 heart transplant recipients and 12 healthy subjects. Additionally, platelet-rich plasma from the patients was incubated with trapidil or with saline, prior to measuring ADP-induced aggregation. The MPV was significantly greater in patients compared to controls (9.4+/-1.1 vs 8.5+/-0.7 fL; P=.01), and ADP-induced platelet aggregation was significantly increased in patients compared to controls (81.2%+/-13.1% vs 69.6%+/-16.2%; P=.04, respectively). The trapidil-treated samples showed significantly decreased platelet aggregation compared to the control samples (24.2%+/-12.6% vs 66.7%+/-11.7%; P<.001). Platelets from heart transplant recipients showed an increased MPV and increased ADP-induced aggregation. Trapidil effectively reduced the ADP-induced aggregation ex vivo.

Atrial fibrillation at discharge from the hospital in patients undergoing mitral valve repair.

BACKGROUND: Patients undergoing mitral valve repair (MVRr) are often discharged on oral anticoagulation with warfarin. Because the decision about oral anticoagulation is made at discharge from the hospital and because atrial fibrillation (AF) represents the only well-documented indication for oral anticoagulation in these patients, we studied the frequency of AF at discharge after MVRr. METHODS: We reviewed the records of 245 patients who underwent MVRr over the past 5 years and assessed the frequency of AF at discharge from the hospital and the factors that were associated with an increased risk for arrhythmia. RESULTS: The group comprised 95 women and 150 men with a mean age of 62.1 +/- 14 years. Seventy-three (30 %) patients were in and/or had a history of AF on admission. Sixty-five (27 %) patients had AF at discharge. Factors that were associated with AF at discharge were: AF on admission (odds ratio [OR] 57.1; confidence interval [CI] 20.8 - 157.3; p < 0.0001), enlarged left atrium (OR 3.2; CI 1.2 - 8.7; p = 0.025) and intake of ACE inhibitors (OR 3.9; CI 1.2 - 12.3; p = 0.022). The OR for AF at discharge in patients with none of the above risk factors was 0.02 (95 % CI 0.02 - 0.13; p < 0.0001). CONCLUSION: Only a relatively small proportion of the studied patients, especially patients with AF on admission, with larger atria and with a history of ACE inhibitors intake, were in AF at discharge after MVRr. Patients with none of these risk factors were at low risk for AF at discharge after MVRr and the optimal oral anticoagulation regimen for these low-risk patients needs to be determined.

Lipid reductions by low-density lipoprotein apheresis: a comparison of three systems.

There are currently three established low-density lipoprotein (LDL) apheresis systems: immunoadsorption, heparin-induced extracorporeal LDL precipitation (HELP), and dextran sulfate. We treated the same patient with all three systems and compared the lipid reductions achieved. A total of 135 consecutive treatments were studied, 57 with immunoadsorption, followed by 30 with HELP and 48 with dextran sulfate adsorption. The mean plasma volume (mean +/- SD) treated was 4.9 +/- 0.05, 3.08 +/- 0.091, and 3.39 +/- 0.71 L, respectively. The LDL-cholesterol (LDL-C) reduction was 75.5% +/- 7.4%, 61.6% +/- 5.1%, and 57.1% +/- 12.4%, respectively (P < .001 for immunoadsorption vHELP and dextran sulfate). The mean removal efficiency (mass removed/plasma volume treated) for LDL-C was 1.0 +/- 0.12, 1.42 +/- 0.25, and 1.15 +/- 0.21 g/L, respectively (P < .001 for HELP v immunoadsorption and dextran sulfate). The mean LDL-C plasma concentration before apheresis was 199 +/- 23.9, 201 +/- 25.7, and 186 +/- 28 mg/dL, respectively (P < .001 for dextran sulfate adsorption v immunoadsorption and HELP). Among the three LDL apheresis systems, immunoadsorption caused the greatest percent reduction in LDL-C, while HELP eliminated LDL-C from the plasma most efficiently. Dextran sulfate was similar to HELP in terms of LDL-C reduction, and its removal efficiency was similar to immunoadsorption. Dextran sulfate was also associated with the lowest pretreatment plasma LDL-C concentration.

Analysis of the long-term efficacy and selectivity of immunoadsorption columns for low density lipoprotein apheresis.

Immunoadsorption low density lipoprotein (LDL) apheresis is performed with reusable columns containing anti-apolipoprotein B(ApoB) antibodies. We analyzed their long-term efficacy and selectivity. Performance over 60 treatment sessions of six pairs of immunoadsorption LDL apheresis columns was evaluated by analysis of variance using the removal of total cholesterol and ApoB to assess efficacy and the ratio of total cholesterol/high density cholesterol removed to assess selectivity. The removal of cholesterol did not vary significantly with treatment number. The mass of ApoB removed increased significantly (p = 0.002), and the mass of ApoB removed per volume unit of processed plasma showed a trend (p = 0.065) toward an increase with treatment number. Both parameters correlated with the serum ApoB concentration before treatment, which also increased significantly (p = 0.0007) with treatment number. No significant variation of selectivity was found. The efficacy of the LDL apheresis immunoadsorption columns did not decrease after 60 treatment sessions. The columns' selectivity also remained unchanged.