Publications by authors named "Hans-Juergen Seyfarth"

14 Publications

  • Page 1 of 1

Increased pulmonary serotonin transporter in patients with chronic obstructive pulmonary disease who developed pulmonary hypertension.

Eur J Nucl Med Mol Imaging 2021 Apr 3;48(4):1081-1092. Epub 2020 Oct 3.

Department of Respiratory Medicine, University Hospital Leipzig, Liebigstrasse 20, 04103, Leipzig, Germany.

Purpose: Pulmonary hypertension (PH) is characterized by a progressive remodelling of the pulmonary vasculature resulting in right heart failure and eventually death. The serotonin transporter (SERT) may be involved in the pathogenesis of PH in patients with chronic-obstructive pulmonary disease (COPD). This study investigated for the first time the SERT in vivo availability in the lungs of patients with COPD and PH (COPD+PH).

Methods: SERT availability was assessed using SERT-selective [C]DASB and positron emission tomography/computed tomography (PET/CT) with dynamic acquisition over 30 min in 4 groups of 5 participants each: COPD, COPD+PH, pulmonary arterial hypertension, and a healthy control (HC). Time activity curves were generated based on a volume of interest within the middle lobe. Tissue-to-blood concentration ratios after 25 to 30 min (TTBR) served as receptor parameter for group comparison and were corrected for lung tissue attenuation. Participants underwent comprehensive pulmonary workup. Statistical analysis included group comparisons and correlation analysis.

Results: [C]DASB uptake peak values did not differ among the cohorts after adjusting for lung tissue attenuation, suggesting equal radiotracer delivery. Both the COPD and COPD+PH cohort showed significantly lower TTBR values after correction for lung attenuation than HC. Attenuation corrected TTBR values were significantly higher in the COPD+PH cohort than those in the COPD cohort and higher in non-smokers than in smokers. They positively correlated with invasively measured severity of PH and inversely with airflow limitation and emphysema. Considering all COPD patients ± PH, they positively correlated with right heart strain (NT-proBNP).

Conclusion: By applying [C]DASB and PET/CT, semiquantitative measures of SERT availability are demonstrated in the lung vasculature of patients with COPD and/or PH. COPD patients who developed PH show increased pulmonary [C]DASB uptake compared to COPD patients without PH indicating an implication of pulmonary SERT in the development of PH in COPD patients.
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http://dx.doi.org/10.1007/s00259-020-05056-7DOI Listing
April 2021

Thoracic [18F]fluorodeoxyglucose uptake measured by positron emission tomography/computed tomography in pulmonary hypertension.

Medicine (Baltimore) 2016 Jun;95(25):e3976

Department of Respiratory Medicine, University of Leipzig, Leipzig, Germany Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany Integrated Research and Treatment Center (IFB) Adiposity Diseases, University of Leipzig, Leipzig, Germany.

Positron emission tomography (PET) visualizes increased cellular [F]fluorodeoxyglucose ([F]FDG) uptake. Pulmonary hypertension (PH) is conceived of a proliferative disease of the lung vessels. Increased glucose uptake can be quantified as pulmonary [F]FDG uptake via PET imaging. Because the angioproliferative mechanisms in PH are still in need of further description, the aim of the present study was to investigate whether [F]FDG PET/CT imaging can elucidate these pathophysiologic mechanisms in different etiologies of PH.Patients (n = 109) with end-stage pulmonary disease being evaluated for lung transplant were included in this observational study. Mean standardized uptake value (SUVmean) of predefined regions of interest in lung parenchyma (LP), left (LV), and right ventricle (RV) of the heart, and SUVmax in pulmonary artery (PA) were determined and normalized to liver uptake. These SUV ratios (SUVRs) were compared with results from right heart catheterization (mean pulmonary artery pressure [mPAP], pulmonary vascular resistance [PVR]), and serum N-terminal pro-brain natriuretic peptide. Group comparisons were performed and Pearson correlation coefficients (r) were calculated.The [F]FDG uptake ratios in LP, RV, RV/LV, and PA, but not in LV, were found to be significantly higher in both patients with mPAP ≥25 mm Hg (P = 0.013, P = 0.006, P = 0.049, P = 0.002, P = 0.68, respectively) and with PVR ≥480 dyn·s/cm (P < 0.001, P = 0.045, P < 0.001, P < 0.001, P = 0.26, respectively). The [F]FDG uptake in these regions positively correlated also with mPAP, PVR, and N-terminal pro-brain natriuretic peptide. The SUVR of PA positively correlated with the SUVR of LP and RV (r = 0.55, r = 0.42, respectively).Pulmonary and cardiac [F]FDG uptake in PET imaging positively correlated with the presence and severity of PH in patients with end-stage pulmonary disease. Increased glucose metabolism in the central PAs seems to play a certain role in terms of severity of PH. These results suggest that [F]FDG-PET imaging can help understand the pathophysiology of PH as a proliferative pulmonary disease.
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http://dx.doi.org/10.1097/MD.0000000000003976DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4998336PMC
June 2016

Elderly patients diagnosed with idiopathic pulmonary arterial hypertension: results from the COMPERA registry.

Int J Cardiol 2013 Sep 17;168(2):871-80. Epub 2012 Nov 17.

Department of Respiratory Medicine and German Center of Lung Research, Hannover Medical School, Hannover, Germany. Electronic address:

Background: Originally reported to occur predominantly in younger women, idiopathic pulmonary arterial hypertension (IPAH) is increasingly diagnosed in elderly patients. We aimed to describe the characteristics of such patients and their survival under clinical practice conditions.

Methods: Prospective registry in 28 centers in 6 European countries. Demographics, clinical characteristics, hemodynamics, treatment patterns and outcomes of younger (18-65 years) and elderly (>65 years) patients with newly diagnosed IPAH (incident cases only) were compared.

Results: A total of 587 patients were eligible for analysis. The median (interquartile, [IQR]) age at diagnosis was 71 (16) years. Younger patients (n=209; median age, 54 [16] years) showed a female-to-male ratio of 2.3:1 whereas the gender ratio in elderly patients (n=378; median age, 75 [8] years) was almost even (1.2:1). Combinations of PAH drugs were widely used in both populations, albeit less frequently in older patients. Elderly patients were less likely to reach current treatment targets (6 min walking distance>400 m, functional class I or II). The survival rates 1, 2, and 3 years after the diagnosis of IPAH were lower in elderly patients, even when adjusted for age- and gender-matched survival tables of the general population (p=0.006 by log-rank analysis).

Conclusions: In countries with an aging population, IPAH is now frequently diagnosed in elderly patients. Compared to younger patients, elderly patients present with a balanced gender ratio and different clinical features, respond less well to medical therapy and have a higher age-adjusted mortality. Further characterization of these patients is required.

Clinical Trials Registration: NCT01347216.
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http://dx.doi.org/10.1016/j.ijcard.2012.10.026DOI Listing
September 2013

Outcomes of noncardiac, nonobstetric surgery in patients with PAH: an international prospective survey.

Eur Respir J 2013 Jun 8;41(6):1302-7. Epub 2012 Nov 8.

Dept of Respiratory Medicine, Hannover Medical School, Hannover, Germany.

We conducted an international, prospective, 3-year questionnaire-based survey among 11 pulmonary hypertension centres to assemble data from patients with pulmonary arterial hypertension (PAH) undergoing noncardiac and nonobstetric surgery. Data were collected between July 2007 and June 2010 from 114 patients with PAH (70% female, mean age 57 years) who underwent major surgery. At the time of surgery, 43% were in functional class III/IV. 82% of the interventions were performed under general anaesthesia and 18% under spinal anaesthesia. Major complications occurred in seven (6.1%) of the patients, of whom four died, resulting in an overall perioperative mortality rate of 3.5%. The mortality rate was 15% (two out of 13) in emergency procedures, compared with 2% (two out of 101) in nonemergency procedures (p=0.01). Risk factors for major complications were an elevated right atrial pressure (OR 1.1, 95% CI 1.0-1.3; p=0.01), a 6-min walking distance <399 m at the last preoperative assessment (OR 2.2, 95% CI 1.1-3.7; p=0.04), the perioperative use of vasopressors (OR 1.5, 95% CI 1.2-2.7; p=0.03) and the need for emergency surgery (OR 2.4, 95% CI 1.4-3.6; p=0.01). Major surgery in patients with PAH continues to be a high-risk procedure, particularly when emergency interventions are needed.
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http://dx.doi.org/10.1183/09031936.00089212DOI Listing
June 2013

Exercise training improves exercise capacity and quality of life in patients with inoperable or residual chronic thromboembolic pulmonary hypertension.

PLoS One 2012 25;7(7):e41603. Epub 2012 Jul 25.

Centre for Pulmonary Hypertension, Thoraxclinic at University Hospital Heidelberg, Heidelberg, Germany.

Background: Aim of this prospective study was to evaluate the effects of exercise training in patients with inoperable or residual chronic thromboembolic pulmonary hypertension (CTEPH).

Methods: Thirty-five consecutive patients with invasively confirmed inoperable or residual CTEPH (16 women;19 men; mean age 61±15 years, mean pulmonary artery pressure, 63±20 mmHg; primary inoperable n = 33, persisting pulmonary hypertension after pulmonary endarterectomy n = 2) on stable disease-targeted medication received exercise training in-hospital for 3 weeks and continued at home for 15 weeks. Medication remained unchanged during the study period. Efficacy parameters have been evaluated at baseline, after 3 and 15 weeks by blinded-observers. Survival rate has been evaluated in a follow-up period of median 36.4 months (interquartile range 26.6-46.6 months).

Results: All patients tolerated exercise training without severe adverse events. Patients significantly improved the mean distance walked in 6 minutes compared to baseline by 61±54 meters after 3 weeks (p<0.001) and by 71±70 meters after 15 weeks (p = 0.001), as well as scores of quality-of-life questionnaire, peak oxygen consumption and maximal workload. NT-proBNP improved significantly after 3 weeks of exercise training (p = 0.046). The 1-year survival rate was 97%, 2-year survival rate was 94% and the 3-year-survival 86% respectively.

Conclusion: Training as add-on to medical therapy may be effective in patients with CTEPH to improve work capacity, quality of life and further prognostic relevant parameters and possibly improves the 1-, 2- and 3-year survival rate. Further multicentric randomized controlled studies are needed to confirm these promising results.

Trial Registration: ClinicalTrials.gov NCT01398345.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0041603PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3404995PMC
April 2013

Standard PAH therapy improves long term survival in CTEPH patients.

Clin Res Cardiol 2010 Sep 25;99(9):553-6. Epub 2010 Apr 25.

Department of Respiratory Medicine, University of Leipzig, Liebigstrasse 20, 04103, Leipzig, Germany.

Background: Chronic thromboembolic pulmonary hypertension (CTEPH), subsequent to pulmonary embolism is a relatively frequent cause of pulmonary hypertension. Similar to patients with pulmonary arterial hypertension (PAH), CTEPH carries a poor prognosis. There is no hard evidence for any other therapy except pulmonary endarterectomy and none for those patients that are not eligible for this procedure.

Patients And Methods: Fifty patients with confirmed, inoperable CTEPH receiving specific vasodilative therapy (prostanoids, endothelin receptor antagonists, PDE 5-inhibitors or combination) were included in this retrospective study (mean age 55 years, range 16-76 years; 36 female, 14 male). Kaplan-Meier plots of these patients were compared with Kaplan-Meier plots of two historical CTEPH patient groups without any specific vasodilative treatment by log rank tests.

Results: CTEPH patients treated with specific vasodilative compounds as used for therapy of PAH were followed up for 52 +/- 30 months and had a significantly improved survival compared with patients treated without PAH type vasodilators (p < or = 0.0002).

Conclusion: Our data may generate the hypothesis that specific vasodilative treatment improves outcome in patients with inoperable CTEPH.
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http://dx.doi.org/10.1007/s00392-010-0156-4DOI Listing
September 2010

Inhaled iloprost for the control of pulmonary hypertension.

Vasc Health Risk Manag 2009 ;5(1):465-74

Department of Respiratory Medicine, University of Leipzig, Leipzig, Germany.

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by an elevated pulmonary arterial pressure and vascular resistance with a poor prognosis. Various pulmonary and extrapulmonary causes are now recognized to exist separately from the idiopathic form of pulmonary hypertension. An imbalance in the presence of vasoconstrictors and vasodilators plays an important role in the pathophysiology of the disease, one example being the lack of prostacyclin. Prostacyclin and its analogues are potent vasodilators with antithrombotic, antiproliferative and anti-inflammatory qualities, all of which are important factors in the pathogenesis of precapillary pulmonary hypertension. Iloprost is a stable prostacyclin analogue available for intravenous and aerosolized application. Due to the severe side effects of intravenous administration, the use of inhaled iloprost has become a mainstay in PAH therapy. However, owing to the necessity for 6 to 9 inhalations a day, oral treatment is often preferred as a first-line therapy. Numerous studies proving the efficacy and safety of inhaled iloprost have been performed. It is therefore available for a first-line therapy for PAH. The combination with endothelin-receptor antagonists or sildenafil has shown encouraging effects. Further studies with larger patient populations will have to demonstrate the use of combination therapy for long-term treatment of pulmonary hypertension.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686263PMC
http://dx.doi.org/10.2147/vhrm.s3223DOI Listing
June 2009

[Spectrum of tuberculous diseases in a pulmonary outpatient clinic].

Med Klin (Munich) 2008 Nov 23;103(11):769-77. Epub 2009 Jan 23.

Internistisch-Pneumologische Praxen, Leipzig, Germany.

Background: Although the incidence of 6.6 newly diagnosed tuberculosis (TB) cases per 100,000 inhabitants is in decline in Germany, TB remains a disease of significant epidemiologic importance.

Patients And Methods: From 04/2001 to 07/2008, a total of 75 TB patients of an internal-pulmonary outpatient clinic had been treated (0.5% of all patients). 58 (77.3%) patients fulfilled the criteria of an active TB, 17 (22.7%) of latent tuberculous infection (LTBI). 68.0% were male (average age men 39.3 +/- 16.9 years [mean +/- standard deviation], women 46.8 +/- 21.5 years; p = not significant). 69.3% of the patients were born in Germany, 30.7% abroad. 84.5% patients had isolated pulmonary, 8.6% additional organ involvement, and 6.9% isolated extrapulmonary TB. 62.1% of active TB cases were microbiologically proven (51.7% microscopically, 43.1% in addition culturally, 6.9% exclusively culturally, 19.0% by polymerase chain reaction [PCR]).

Results: Of 23 tests, 52.2% were fully sensitive against the most important first-line drugs ethambutol (M), isoniazid (H), rifampicin (R), pyrazinamide (Z), und streptomycin (S). 13.0% had an isolated resistance against H (4.4%) or S (8.6%), 4.4% a multiple drug resistance (MDR) against R und H, 30.4% a polyresistance (S and H). Symptoms were quite often unspecific, not taken care of, or misinterpreted.

Conclusion: Diagnosis and therapy of an active or latent TB illness remains, an important task and challenge, necessitating an effective cooperation of outpatient, hospital, and health authority institutions.
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http://dx.doi.org/10.1007/s00063-008-1120-1DOI Listing
November 2008

Inhaled iloprost for hepatopulmonary syndrome: improvement of hypoxemia.

Eur J Gastroenterol Hepatol 2007 Dec;19(12):1140-3

Department of Pulmonary Medicine, University of Leipzig, Leipzig, Germany.

Hepatopulmonary syndrome is characterized by advanced liver disease, hypoxemia, and intrapulmonary shunting. The only reported curative option is orthotopic liver transplantation. We describe here a beneficial effect of inhaled prostacyclin including a decrease in respiratory symptoms and improved oxygenation in this clinical situation, with no approved pharmacological long-term therapy. The prostanoid iloprost, approved for pulmonary and portopulmonary hypertension, caused an increase in oxygenation, relief of dyspnea, and increased exercise tolerance in a patient suffering from liver-cirrhosis-associated hepatopulmonary syndrome. After liver transplantation, restitution of hepatopulmonary syndrome did not occur immediately. Inhaling iloprost resulted in improved physical condition and better clinical rehabilitation potential until hypoxemia finally resolved 3 months after transplantation. Therefore, iloprost could improve quality of life in patients with hepatopulmonary syndrome waiting for liver transplantation and post surgery until the resolution of the hypoxemia.
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http://dx.doi.org/10.1097/MEG.0b013e328220ed72DOI Listing
December 2007

Complications of right heart catheterization procedures in patients with pulmonary hypertension in experienced centers.

J Am Coll Cardiol 2006 Dec 28;48(12):2546-52. Epub 2006 Nov 28.

Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany.

Objectives: This study sought to assess the risks associated with right heart catheter procedures in patients with pulmonary hypertension.

Background: Right heart catheterization, pulmonary vasoreactivity testing, and pulmonary angiography are established diagnostic tools in patients with pulmonary hypertension, but the risks associated with these procedures have not been systematically evaluated in a multicenter study.

Methods: We performed a multicenter 5-year retrospective and 6-month prospective evaluation of serious adverse events related to right heart catheter procedures in patients with pulmonary hypertension, as defined by a mean pulmonary artery pressure >25 mm Hg at rest, undergoing right heart catheterization with or without pulmonary vasoreactivity testing or pulmonary angiography.

Results: During the retrospective period, 5,727 right heart catheter procedures were reported, and 1,491 were reported from the prospective period, for a total of 7,218 right heart catheter procedures performed. The results from the retrospective and the prospective analyses were almost identical. The overall number of serious adverse events was 76 (1.1%, 95% confidence interval 0.8% to 1.3%). The most frequent complications were related to venous access (e.g., hematoma, pneumothorax), followed by arrhythmias and hypotensive episodes related to vagal reactions or pulmonary vasoreactivity testing. The vast majority of these complications were mild to moderate in intensity and resolved either spontaneously or after appropriate intervention. Four fatal events were recorded in association with any of the catheter procedures, resulting in an overall procedure-related mortality of 0.055% (95% confidence interval 0.01% to 0.099%).

Conclusions: When performed in experienced centers, right heart catheter procedures in patients with pulmonary hypertension are associated with low morbidity and mortality rates.
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http://dx.doi.org/10.1016/j.jacc.2006.07.061DOI Listing
December 2006

Portopulmonary hypertension.

J Gastroenterol 2006 Sep;41(9):837-47

Carl Gustav Carus University Dresden, Internal Medicine I, Fetscherstr. 74, 01307 Dresden, Germany.

Portopulmonary hypertension (PPHT) is defined as precapillary pulmonary hypertension accompanied by hepatic disease or portal hypertension. Pulmonary hypertension results from excessive pulmonary vascular remodeling and vasoconstriction. These histological alterations have been indistinguishable from those of other forms of pulmonary arterial hypertension. Factors involved in the pathogenesis of PPHT include volume overload, hyperdynamic circulation, and circulating vasoactive mediators. The disorder has a substantial impact on survival and requires focused treatment. Liver transplantation in patients with moderate to severe PPHT is associated with a significantly reduced survival rate. The best medical treatment for patients with PPHT is controversial; most authors currently regard continuous intravenous application of prostacyclin as the treatment of choice for patients with severe PPHT. There is only very limited reported experience with inhaled prostacyclin or its analog, iloprost. Increasing evidence of the efficacy of the endothelin-receptor antagonist bosentan and of the phosphodiesterase-5 inhibitor sildenafil is emerging in highly selected patients with PPHT. In the future, a combination therapy of the above-mentioned agents might become a therapeutic option. Other agents such as beta-blockers seem to be harmful to patients with moderate to severe portopulmonary hypertension. Up-to-date, randomized, double-blind, controlled clinical trials are lacking and are needed urgently.
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http://dx.doi.org/10.1007/s00535-006-1879-xDOI Listing
September 2006

Different mechanisms for changes in glucose uptake of the right and left ventricular myocardium in pulmonary hypertension.

J Nucl Med 2005 Jan;46(1):25-31

Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany.

Unlabelled: In patients with pulmonary hypertension (PH) the right ventricular (RV)-to-left ventricular (LV) ratio of fatty acid uptake is reduced. In animal studies, such a finding was combined with an increased glucose uptake in RV myocardium. The aim of this study was to measure the metabolic rates of glucose uptake for the RV and LV myocardium in patients in relationship to parameters of RV and LV function.

Methods: Thirty patients with PH underwent PET with (18)F-FDG and SPECT with (99m)Tc-tetrofosmine. The metabolic rate of glucose uptake was determined for RV and LV myocardium using the method of Patlak. A right heart catheter, thermodilution, and Doppler sonography were used to characterize RV and LV function. From these methods, the stroke work of both ventricles and the RV Tei index were calculated.

Results: RV-to-LV ratios of (18)F-FDG-uptake increased with rising pulmonary arteriolar resistance (PAR). With increasing PAR, the metabolic rate of glucose uptake of the left ventricle decreased (r = -0.547; P < 0.01) together with LV stroke work (r = -0.838; P < 0.001). The metabolic rate of glucose uptake of the right ventricle, however, correlated neither with RV stroke work (r = 0.124) nor with PAR (r = 0.189) but with the Tei index (r = 0.78; P < 0.001).

Conclusion: Increasing right-to-left ratios of glucose uptake with an increasing pressure load in the right ventricle in PH are caused mainly by a significant reduction in the LV metabolic rate of glucose uptake. This is obviously due to a reduced energy demand of the LV myocardium caused by reduced stroke work. An increased metabolic rate of glucose uptake in the right ventricle presumably indicates RV impairment, correlating with the Tei index, which is an established prognostic parameter for cardiac dysfunction and poor survival.
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January 2005

Fibrinogen receptor antagonists induce conformational changes of the human platelet glycoprotein IIb.

Cytometry B Clin Cytom 2004 Nov;62(1):14-24

Department of Pneumology, University of Leipzig, Leipzig, Germany.

Background: Controversial results have been reported concerning the ability of fibrinogen receptor antagonists (fibans) to induce conformational changes in the fibrinogen receptor after binding to it as the initial step of fibrinogen binding and platelet activation.

Methods: Platelets in citrated whole blood were stained with several pairs of anti-glycoprotein (anti-GP) IIb-directed monoclonal antibodies conjugated to phycoerythrin (PE) or indirectly labeled with Cy5. Pairs of monoclonal antibodies that induced a high-fluorescence resonance energy transfer (FRET) efficiency served as tools to detect activation-dependent changes of GP IIb after addition of adenosine diphosphate and several fibans.

Results: Using the combination of the clones 5B12-PE and P2-biotin/SA-Cy5, a concentration-dependent alteration of the GP IIb conformation was observed after addition of tirofiban, eptifibatide, and lotrafiban. Magnitude and kinetics differed among the investigated substances.

Conclusion: The newly developed FRET assay allows the direct investigation of conformational changes of GP IIb after addition of platelet agonists or receptor ligands, as shown for three fibans.
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http://dx.doi.org/10.1002/cyto.b.20026DOI Listing
November 2004

Effect of 300- and 450-mg clopidogrel loading doses on membrane and soluble P-selectin in patients undergoing coronary stent implantation.

Am Heart J 2002 Jan;143(1):118-23

Department of Pneumology, University of Leipzig, Leipzig, Germany.

Background: After coronary artery stent implantation patients are treated with the adenosine diphosphatase (ADP) receptor antagonist clopidogrel to prevent subacute stent thromboses. Today these patients initially receive a loading dose of 300 mg of clopidogrel to accelerate the complete drug effect. In the current study we investigated whether a higher loading dose can shorten the time until the maximum platelet inhibitory effect of clopidogrel is achieved.

Methods: P-selectin expression of nonstimulated and ADP-stimulated platelets was flow cytometrically measured before the clopidogrel loading dose and on 3 consecutive days in 52 patients with coronary artery disease: 21 patients in group 1 received 300 mg of clopidogrel after stent implantation and 11 patients in group 2 received the higher 450-mg clopidogrel loading dose followed by a daily dose of 75 mg of clopidogrel for both groups. The control group consisted of 20 patients who were monitored over 2 days before coronary intervention. Soluble P-selectin levels in plasma were determined by an enzyme-linked immunosorbent assay.

Results: Inducible P-selectin expression on ADP-stimulated platelets was significantly reduced (P =.05) on days 1 and 2 in patient group 2 (450-mg loading dose) compared with group 1 (300-mg loading dose). No influence of clopidogrel on the P-selectin levels in plasma was observed.

Conclusions: In our study the application of 450 mg of clopidogrel as the loading dose in patients undergoing coronary stenting shortens the period until the maximum effect of the ADP receptor antagonist is achieved and thus may lead to a more successful prevention of subacute coronary stent thromboses.
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http://dx.doi.org/10.1067/mhj.2002.119372DOI Listing
January 2002