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ABSTRACT: Die klinische Wirksamkeit von GP IIb/IIIa Antagonisten wurde bei präinterventioneller prophylaktischer Applikation in großen
klinischen Studien nachgewiesen. Ziel dieser prospektiven Studie war es, die Wirksamkeit von Abciximab bei der Anwendung in
„bail-out” Situationen zu untersuchen.¶ Methoden: Insgesamt wurden bei 104 (5,5%) der 1903 Patienten, welche im Beobachtungszeitraum in unserem Zentrum dilatiert wurden, akute
oder drohende Gefäßverschlüsse beobachtet. In dieser Situation wurde Abciximab in einer Dosierung von 0,25mg/kg als Bolus,
gefolgt von einer Infusion von 10μg/min über 12 Stunden appliziert. Kurz nach der Gabe des Bolus wurde eine erneute PTCA durchgeführt.
Am Ende der Intervention wurde die Schleuse belassen und nach 24 Std. eine Kontrollangiographie durchgeführt.¶ Ergebnisse: Bei 100 der 104 Patienten konnte ein ausreichender (TIMI III) Fluss wiederhergestellt werden. Bei 4 Patienten war die zusätzliche
Implantation eines Stents notwendig. Eine Kontrollangiographie am Folgetag zeigte in allen bis auf 2 Fälle offene Gefäße mit
gutem antegraden Fluss (TIMI III). Bei 4 Patienten trat nach der Intervention ein subakuter Gefäßverschluss auf. Drei von
ihnen verstarben trotz einer sofort durchgeführten Notfall-ACVB OP. Das 12 Monats Follow-up beinhaltet den klinischen Status
sowie eine Kontrollangiographie des Zielgefäßes. Während des Nachbeobachtungszeitraums kam es bei 15 Patienten zu einem klinischen
Ereignis (2 MI, 8 ACVB, 5 Re-PTCA).¶ Schlussfolgerung: Die Ergebnisse dieser prospektiven Studie zeigen die hohe Wirksamkeit von Abciximab in „bail-out” Situationen während oder
direkt nach der PTCA. Weitere Studien sollten dieses Konzept mit dem der prophylaktischen Behandlung vergleichen.
The administration of GP IIb/IIIa antagonists has been shown to be effective in reducing myocardial infarction and cardial
death when given before PTCA. This prospective study was performed to determine the efficacy of abciximab in a bail-out situation
to manage threatened or acute vessel closure.¶ Methods: Acute or threatened vessel closure was observed in 104 (5.5%) out of 1903 consecutive patients treated with PTCA in our institution.
Of the 104 patients 46 (44%) were treated for unstable angina (CCS IV). Abciximab was administered in bail-out situations
in a dosage of 0.25mg/kg given as a bolus, which was followed by an intravenous infusion of 10μg/min over 12 hours. Repeat
PTCA was performed shortly after the administration of the abciximab bolus. After the procedure, the sheathe was left in place
and control angiography was carried out 24 h later.¶ Results: In 100 of the 104 patients TIMI flow III could be restored by abciximab therapy and RePTCA. In 4 patients an additional stent
implantation was necessary due to persistent flow limitation. One day post PTCA, early follow-up angiography demonstrated
patency of all vessels except two. In-hospital events occurred in 4 patients. Three of these patients underwent emergency
CABG due to subacute vessel closure a few hours after PTCA and died during or directly after surgery. Follow-up after one
year included clinical status and control angiography of the target vessel. During long-term follow-up, MACE occured in 15
patients (2 MI, 8 CABG and 5 RePTCA).¶ Conclusion: The results of this prospective trial demonstrate the efficacy of abciximab
therapy in bail-out situations occurring during or early after PTCA. The use of abciximab in bail-out situations appears clinically
beneficial. Further studies have to compare the efficacy of this approach with prophylactic abciximab treatment.
Schlüsselwörter PTCA – GP IIb/IIIa Antagonisten –¶Akuter GefäßverschlussKey words PTCA –¶GP IIb/IIIa antagonists –¶abrupt vessel closure
Zeitschrift für Kardiologie 04/2012; 89(8):722-729. · 0.97 Impact Factor
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ABSTRACT: This experimental study was designed to define the potential value of a mid-infrared holmium laser in the free running mode for angioplasty. Immediately after removal, fresh normal and diseased human cadaveric arteries were irradiated under saline with a Ho:YAG laser (wavelength 2.13 μm). The laser was pulsed at 3 Hz, 250 μs pulse width and fluences of 10 to 40 J/cm2. The laser beam was coupled to ring catheters with multiple low-OH quartz fibers. The tip of the delivery device was held in direct contact with the vessel surface with the laser beam oriented perpendicularly. Ablation of atherosclerotic plaque was accomplished at an ablation threshold of 10 J/cm2. The ablation rate was 2.1 to 8.3 μm/pulse. Removal of calcified plaque was only partially effective. There were marked thermal effects with vacuolizations extending up to 1505 ± 178 μm into the adjacent tissue. Laser light at the mid-infrared wavelength of 2.13 μm is supposed to be attractive as it is readily absorbed in water and can easily be transmitted through optical fibers. However, Q-switching seems to be essential to minimize thermal side effects and to make effective ablation of calcium possible.
01/2010; 33(6):538-541.
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ABSTRACT: Coronary stents have considerably improved both immediate and late results after coronary angioplasty, by limiting elastic recoil and vascular remodeling, but their use does not eliminate restenosis, caused mainly by neointimal hyperplasia. Stents are now implanted in over 70% of percutaneous coronary interventions. More than 50 coronary stents have already been approved in Europe and over 20 stents are commercially available in the USA, raising the question: which device is best suitable for which lesion? Several in vitro experiments revealed significant differences in expansion characteristics of coronary stents, related to the strut design and metallic composition. Animal studies were performed to determine the influence of stent design on the patterns and extent of neointimal hyperplasia. However, the clinical results of randomized trials comparing stent types in humans have not always reflected laboratory findings. This article is a critical overview of experimental and clinical data concerning the impact of stent design on the early and late clinical outcome after coronary stent implantation.
07/2009; 11(4):203-209.
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ABSTRACT: Glycoprotein-IIb/IIIa inhibitors are now frequently used in the cardiological treatment of high-risk coronary patients even if the patient is considered suitable for surgical intervention. However, there is no consensus whether GPIIb/IIIa inhibitors should be stopped before operation because of an increased risk of bleeding or if surgery should even be delayed until the anticoagulating effect subsides.
From June 2002 to August 2003 140 patients who had to undergo primary aorto-coronary bypass for ongoing myocardial ischemia were enrolled in the present study. The patients received either clopidogrel, aspirin and heparin or additionally abciximab until operation.
Although the intraoperative need for blood products was higher in the abciximab group, there was no significant difference in postoperative blood loss. The hemodynamic situation of the abciximab patients after the operation was better compared to the other groups. 30-day mortality was not increased when compared to the elective control group (6.7 % vs. 6.1 %).
The GPIIb/IIIa inhibitor abciximab can be safely used as a bridge to operation and results in a better hemodynamic outcome in high-risk coronary patients while reducing the incidence of major ischemic events.
The Thoracic and Cardiovascular Surgeon 05/2006; 54(3):150-6. · 0.88 Impact Factor
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ABSTRACT: Newer techniques are required to identify atherosclerotic lesions that are prone to rupture. Electric impedance spectroscopy (EIS) can characterize biological tissues by measuring the electrical impedance over a frequency range. We tested a newly designed intravascular impedance catheter (IC) by measuring the impedance of different stages of atherosclerosis induced in an animal rabbit model. Six female New Zealand White rabbits were fed for 17 weeks with a 5% cholesterol-enriched diet to induce early forms of atherosclerotic plaques. All aortas were prepared from the aortic arch to the renal arteries and segments of 5-10 mm were marked by ink spots. A balloon catheter system with an integrated polyimide-based microelectrode structure was introduced into the aorta and the impedance was measured at each spot by using an impedance analyzer. The impedance was measured at frequencies of 1 kHz and 10 kHz and compared with the corresponding histomorphometric data of each aortic segment.Forty-four aortic segments without plaques and 48 segments with evolving atherosclerotic lesions could be exactly matched by the histomorphometric analysis. In normal aortic segments (P0) the change of the magnitude of impedance at 1 kHz and at 10 kHz (|Z|(1 kHz) - |Z|(10 kHz), = ICF) was 208.5 +/- 357.6 Omega. In the area of aortic segments with a plaque smaller than that of the aortic wall diameter (PI), the ICF was 137.7 +/- 192.8 Omega. (P 0 vs. P I; p = 0.52), whereas in aortic segments with plaque formations larger than the aortic wall (PII) the ICF was significantly lower -22.2 +/- 259.9 Omega. (P0 vs. PII; p = 0.002). Intravascular EIS could be successfully performed by using a newly designed microelectrode integrated onto a conventional coronary balloon catheter. In this experimental animal model atherosclerotic aortic lesions showed significantly higher ICF in comparison to the normal aortic tissue.
Archiv für Kreislaufforschung 10/2005; 100(5):446-52. · 7.35 Impact Factor
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ABSTRACT: Stress echocardiography (SE) has become a widely accepted clinical tool for the non-invasive diagnosis of coronary artery disease (CAD). Previous studies have confirmed that SE has superior diagnostic value compared to exercise ECG testing. SE has also emerged as a cost-effective alternative to nuclear imaging techniques in patients where symptoms and/or conventional ECG stress testing have provided ambiguous results. Several studies have investigated the value of SE to detect significant restenosis after PTCA. However, in these studies, different methods have been used to induce cardiovascular stress such as physical exercise by bicycle or treadmill, pharmacologic stress testing (with dipyridamole or dobutamine) or transoesphageal atrial pacing. This review evaluates the published database of SE to detect restenosis in patients after successful PTCA. It includes 13 studies with a total of 989 patients performed at 3-6 months after the primary intervention. The diagnostic value, utility and limitations of SE is presented and discussed. The data show that SE has a high diagnostic value for detecting significant restenosis after PTCA. Mean sensitivity of SE was 74% (CI 69-79%), mean specificity was 87% (CI 84-89%). The positive predictive value (PPV) of SE was 83%, the overall negative predictive value (NPV) 97%. We conclude that, in the follow-up of patients after PTCA, SE has distinct advantages over other non-invasive methods and is a recommended method for the detection of those to be considered for repeat angiography.
International Journal of Cardiology 03/2005; 98(2):191-7. · 7.08 Impact Factor
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ABSTRACT: We describe the case of a 61-year-old woman who simultaneously suffered a pulmonary embolism and a myocardial infarction due to paradoxical coronary artery embolism. Transesophageal echocardiography with injection of agitated hydroxyethyl starch revealed a patent foramen ovale. Thrombophlebistis of the left saphenous vein with extension of thrombus into the femoral vein could be identified as the source of embolism. Paradoxical coronary embolism is an underrecognized cause of MI. Diagnosis is particularly difficult, when MI and PE coincide, because of the similarity in clinical signs and symptoms of both entities. A high level of clinical suspicion and echocardiography, especially if performed soon after presentation, can be the clue to early diagnosis of PDE.
Zeitschrift für Kardiologie 11/2004; 93(10):824-8. · 0.97 Impact Factor
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ABSTRACT: Non-anticoagulant biological activities, such as anti-inflammatory and anti-apoptotic mechanisms of action, have been suggested for recombinant human activated protein C (rhAPC; drotrecogin alfa (activated)). However, these mechanisms are much less characterized and understood than rhAPC's anticoagulant activity. Aim of the study was to determine the effect of rhAPC on the activity of the pro-inflammatory transcription factor nuclear factor kappa B (NF-kappaB) in mononuclear cells isolated from septic patients and to characterize an effect downstream from NF-kappaB activation, such as the release of the NF-kappaB-controlled chemokine Macrophage Inflammatory Protein-1-alpha (MIP-1-alpha).
Peripheral blood was obtained from 13 septic patients and from 8 healthy controls.
Mononuclear cells were isolated by Ficoll-Paque density gradient centrifugation and were incubated with or without rhAPC (10 microg/ml) for 2 h for the measurement of NF-kappaB activity in cell lysates or alternatively for 6 h for the determination of MIP-1-alpha levels in supernatants. NF-kappaB activity was measured by an ELISA-based assay directed against the p50 and the p65 subunit of NF-kappaB.
RhAPC, at supra-pharmacological concentration (10 microg/ml), significantly inhibited NF-kappaB activity and the release of MIP-1-alpha ex vivo in isolated mononuclear cells from patients with severe sepsis. In mononuclear cells of healthy subjects, however, rhAPC did not change NF-kappaB activity. Basal NF-kappaB activity early in severe sepsis was not predictive for survival.
RhAPC at supra-pharmacological concentration (10 microg/ml) inhibits the activity of NF-kappaB in ex vivo isolated mononuclear cells of septic patients as well as the release of MIP-1-alpha, a proinflammatory chemokine regulated by NF-kappaB. These findings may represent immunomodulatory pathways by which rhAPC exerts specific anti-inflammatory activity in vitro in addition to its known anticoagulant and profibrinolytic activity and should be further investigated in an in vivo setting.
Inflammation Research 11/2004; 53(10):528-33. · 2.11 Impact Factor
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ABSTRACT: To assess the incidence and electrophysiological characteristics of spontaneous ventricular tachyarrhythmias after implantable cardioverter-defibrillator (ICD) implantation for primary prevention.
Prospective observational study.
41 consecutive patients, who fulfilled MADIT (multicenter automatic defibrillator implantation trial) I criteria, except for suppressibility by procainamide, and who received a prophylactic ICD.
Subpectoral implantation of an ICD.
Incidence of ventricular tachyarrhythmias and their electrophysiological characteristics with respect to timing of the arrhythmia, tachyarrhythmia cycle length, mode of termination, and clinical relevance.
During a mean (SD) follow up of 30 (21) months 18 of 41 (43.9%) patients experienced 142 appropriate ICD treatments. The mean (SD) time to first event was 9.6 (15.1) months. One patient had ventricular fibrillation (VF), 12 patients ventricular tachycardia (VT), and five both VT and VF. The mean (SD) cycle length of monomorphic VT was 306 (42) ms. Of 142 episodes, 117 (82.3%) were terminated by antitachycardia pacing and another 25 (17.6%) by ICD discharges. Cumulative survival of hypothetical death, defined as treated VT with a cycle length < 260 ms or VF, was 83.2% after one year and 78.4% after two years.
Patients with a left ventricular ejection fraction < 35%, a history of myocardial infarction, non-sustained VT, and inducible VT/VF are at high risk of VT/VF early after implantation. Therefore, implantation of a tiered treatment defibrillator seems to be justified.
Heart (British Cardiac Society) 07/2004; 90(6):667-71. · 4.22 Impact Factor
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ABSTRACT: Calcific aortic stenosis is the main heart valve disease in the elderly, leading to massive focal calcification and thickening of the valve cusps. Matrix metalloproteinases (MMPs) are thought to contribute to this process. Therefore, the study assessed the expression of the gelatinases MMP-2 and MMP-9 and the endogenous tissue inhibitor of metalloproteinase (TIMP)-2 as well as the gelatinolytic activity in normal and stenotic valves. Human tricuspid aortic valves with and without calcific aortic stenosis were studied by immunohistochemistry for MMP-2, MMP-9 and TIMP-2. The gelatinolytic activity in native valve sections was assessed by gelatin in situ zymography with or without addition of the MMP activator p-aminophenymercuric acetate (APMA). Staining intensities for MMP-2 and TIMP-2 were elevated in stenotic valves as compared to controls. Minor staining of MMP-9 was present exclusively in stenotic valves. The morphologic distribution of gelatinolytic activity was comparable to the staining pattern of MMP-2, and since MMP-9 immunostaining demonstrated only a low number of positive cells, the observed gelatinolytic activity is likely due to MMP-2. Gelatinolytic activity was low in normal valves but significantly increased by the MMP activator APMA. In contrast, stenotic valves showed a strong basal gelatinolytic activity that could not be significantly enhanced by APMA suggesting that MMP-2 is present as a latent pro-enzyme in normal valves and activated in stenotic valves. Thus, MMP-2 might be involved in the matrix remodeling during calcific aortic stenosis.
Zeitschrift für Kardiologie 03/2004; 93(2):124-30. · 0.97 Impact Factor
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ABSTRACT: Calcific aortic stenosis is the main heart valve disease
in the elderly, leading to massive focal calcification and
thickening of the valve cusps. Matrix metalloproteinases (MMPs)
are thought to contribute to this process. Therefore, the study
assessed the expression of the gelatinases MMP-2 and MMP-9 and
the endogenous tissue inhibitor of metalloproteinase (TIMP)-2 as
well as the gelatinolytic activity in normal and stenotic
valves. Human tricuspid aortic valves with and without calcific
aortic stenosis were studied by immunohistochemistry for MMP-2,
MMP-9 and TIMP-2. The gelatinolytic activity in native valve
sections was assessed by gelatin in situ zymography with or
without addition of the MMP activator p-aminophenymercuric
acetate (APMA). Staining intensities for MMP-2 and TIMP-2 were
elevated in stenotic valves as compared to controls. Minor
staining of MMP-9 was present exclusively in stenotic valves.
The morphologic distribution of gelatinolytic activity was
comparable to the staining pattern of MMP-2, and since MMP-9
immunostaining demonstrated only a low number of positive cells,
the observed gelatinolytic activity is likely due to MMP-2.
Gelatinolytic activity was low in normal valves but
significantly increased by the MMP activator APMA. In contrast,
stenotic valves showed a strong basal gelatinolytic activity
that could not be significantly enhanced by APMA suggesting that
MMP-2 is present as a latent pro-enzyme in normal valves and
activated in stenotic valves. Thus, MMP-2 might be involved in
the matrix remodeling during calcific aortic stenosis.Die degenerativ- kalzifizierende Aortenstenose ist die
hufigste Herzklappenerkrankung und Hauptursache eines
Herzklappenersatzes im fortgeschrittenen Alter. Sie fhrt zu
massiver Verkalkung sowie zu einem extensivem Umbau der
extrazellulren Matrix; es wird vermutet, dass
Matrix-Metalloproteinasen (MMPs) hierbei eine pathogenetische
Rolle spielen. Wir untersuchten daher die Expression der
Gelatinase MMP-2 und MMP-9 sowie ihres endogenen Inhibitors
Tissue Inhibitor of Metalloproteinase-2 (TIMP-2) sowie die
gelatinolytische Aktivitt in 24 stenotischen und 8 normalen
Aortenklappen. In der immunhistochemischen Frbung zeigten die
stenotischen Klappen eine signifikant hhere Frbeintensitt fr
MMP-2 und TIMP-2 im Vergleich zu den Kontrollklappen. Eine
geringe Frbung von MMP-9 war ausschlielich bei stenotischen
Klappen nachweisbar. In der in situ Zymographie wiesen normale
Klappen eine minimale basale gelatinolytische Aktivitt auf, die
durch Zugabe des MMP-Aktivators p-Aminophenymercuroazetat (APMA)
signifikant gesteigert werden konnte. In stenotischen Klappen
war hingegen eine deutlich vermehrte Enzymaktivitt nachweisbar,
die durch Zugabe von APMA nicht mehr signifikant gesteigert
werden konnte. MMP-2 und TIMP-2 zeigen somit eine differentielle
Expression bei kalzifizierender Aortenstenose. MMP-2 liegt in
normalen Klappen vorwiegend als inaktives Proenzym vor, in
stenotischen Klappen hingegen in der aktivierten Form. Diese
Ergebnisse sprechen fr einen durch MMP-2 vermittelten Umbau der
extrazellulren Matrix bei kalzifizierender
Aortenstenose.
Zeitschrift für Kardiologie 01/2004; 93(2):124-130. · 0.97 Impact Factor
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ABSTRACT: Coronary stenting has become the primary therapeutic option for many coronary lesions. As opposed to conventional stenting the advantages of direct stenting are a reduction of procedural time, radiation exposure and costs. However, data about the incidence of in-stent restenosis are so far not available. It was the aim of this prospective study to compare the expansion of the Multilink stent after direct stenting and predilatation by quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). Between January 2000 and June 2001, 82 patients were assigned to direct stenting (46 lesions) or predilatation (40 lesions) in lesions of coronary arteries > 3 mm. The procedural success rate was 92% in patients undergoing direct stenting. The baseline clinical characteristics were similar in both groups. The comparison of the angiographic data shows that direct stenting was performed in lesions with a lower degree of stenosis (71 +/- 12% vs 79 +/- 11%, p = 0.01) and that significantly shorter stents were used (14.4 +/- 3.0 vs 17.8 +/- 4.1 mm, p = 0.0007). The mean stenosis length was not significantly different in either group (10.5 +/- 3.4 vs 11.7 +/- 4.3 mm, n.s.). The QCA data after stent implantation show no differences of either implantation technique. Stent expansion was assessed by IVUS estimation of the proximal, distal and minimal in stent area. The minimal in-stent area (9.53 +/- 3.23, mm2 vs 8.65 +/- 1.96 mm2, n.s.) and the stent symmetry index (0.88 vs 0.88 n.s.) were not different in either patient group. These results indicate that in this subset of selected coronary lesions > 3 mm, elective stent implantation with and without predilatation effectively can achieve comparable stent expansion as assessed by QCA and IVUS. In comparison to conventional stent implantation stents, which were implanted without predilatation, were significantly shorter to cover the same lesion length.
Zeitschrift für Kardiologie 07/2002; 91(6):487-92. · 0.97 Impact Factor
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ABSTRACT: Summary Coronary stenting has become the primary therapeutic option for many coronary lesions. As opposed to conventional stenting the advantages of direct stenting are a reduction of procedural time, radiation exposure and costs. However, data about the incidence of in-stent restenosis are so far not available. It was the aim of this prospective study to compare the expansion of the Multilink stent after direct stenting and predilatation by quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). Between January 2000 and June 2001, 82 patients were assigned to direct stenting (46 lesions) or predilatation (40 lesions) in lesions of coronary arteries >3mm. The procedural success rate was 92% in patients undergoing direct stenting. The baseline clinical characteristics were similiar in both groups. The comparison of the angiographic data shows that direct stenting was performed in lesions with a lower degree of stenosis (71ᆠ% vs 79ᆟ%, p=0.01) and that significantly shorter stents were used (14.4Dž.0 vs 17.8dž.1 mm, p=0.0007). The mean stenosis length was not significantly different in either group (10.5Dž.4 vs 11.7dž.3 mm, n.s.). The QCA data after stent implantation show no differences of either implantation technique. Stent expansion was assessed by IVUS estimation of the proximal, distal and minimal in-stent area. The minimal in-stent area (9.53Dž.23mm2 vs 8.65ǃ.96mm2, n.s.) and the stent symmetry index (0.88 vs 0.88 n.s.) were not different in either patient group. These results indicate that in this subset of selected coronary lesions >3 mm, elective stent implantation with and without predilatation effectively can achieve comparable stent expansion as assessed by QCA and IVUS. In comparison to conventional stent implantation stents, which were implanted without predilatation, were significantly shorter to cover the same lesion length. Zusammenfassung Die direkte Stentimplantation zeichnet sich durch einen hohen prozeduralen Erfolg bei geringer Komplikationsrate aus. In zahlreichen Untersuchungen konnte nachgewiesen werden, dass durch die direkte Stentimplantation neben der Dauer der Behandlung und der Hhe der Strahlenexposition auch die Kosten der Behandlung signifikant gesenkt werden knnen. Zur Zeit liegen jedoch nur geringe Daten zur Inzidenz der Restenose nach direkter Stentimplantation vor. Es war Ziel der vorliegenden Arbeit, mittels intravaskulren Ultraschall (IVUS) die Expansion des Multilink-Tristar-Stents (Guidant, Temecula, Kalifornien, USA) nach direkter Implantation zu untersuchen und mit der Expansion in vordilatierten Gefen zu vergleichen. Insgesamt wurden 82 Patienten mit 86 Lsionen in Koronargefen >3 mm prospektiv untersucht. Bei 46 Lsionen wurde der Multilink-Tristar-Stent mit einer Erfolgsrate von 92% direkt implantiert, bei 40 Lsionen erfolgte die Stentimplantation nach Vordilatation des Gefes. Der Vergleich der beiden Gruppen zeigt, dass die direkte Stentimplantation hufiger in Koronarlsionen mit geringerem Stenosegrad (71ᆠ% vs. 79ᆟ%, p=0,01) durchgefhrt wurde. Zur Abdeckung gleicher Lsionslngen (10,5Dž,4 vs. 11,7dž,3 mm, n.s.) wurden bei der direkten Stentimplantation signifikant krzere Stents (14,4Dž,0 vs. 17,8dž,1 mm, p=0,0007) im Vergleich zur Vordilatation gewhlt. Die Ergebnisse der quantitativen Koronarangiographie (QCA) zeigten keine signifikanten Unterschiede zwischen den beiden Implantationstechniken. Mittels quantitativer IVUS-Analyse konnte nachgewiesen werden, dass beide Implantationstechniken zu vergleichbaren minimalen Instentflchen (ISF) (9,53Dž,23mm2 vs. 8,65ǃ,96mm2, n.s.) und Expansionen (Stentsymmetrieindex 0,88 vs. 0,88 n.s.) fhrten. Zusammenfassend lsst sich feststellen, dass die Technik der direkten Stentimplantation in Koronargefen >3mm einen Lumengewinn und Stentexpansion erreicht, der dem der Stentimplantation nach Vordilatation vergleichbar ist. Im Vergleich zur Stentimplantation nach Vordilatation sind hierbei die gewhlten Stentlngen signifikant krzer.
Zeitschrift für Kardiologie 05/2002; 91(6):487-492. · 0.97 Impact Factor
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ABSTRACT: In the event of chest pain developing, the task of initial evaluation must be either to confirm and treat an acute life-threatening condition, or to exclude it. The diagnosis of a harmless functional disorder can be established only after the exclusion of a number of cardiovascular, pulmonary or gastrointestinal conditions, as also infection or malignancy. Such an approach often requires cooperation with orthopedic surgeons, general surgeons, psychiatrists and also pain specialists.
MMW Fortschritte der Medizin 05/2002; 144(17):24-6.
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ABSTRACT: The high mortality rate of acute myocardial infarction underline the importance of this entity in the differential diagnosis of acute chest pain. Medical history, clinical presentation, ECG, biochemical markers of myocardial injury and imaging techniques are used to establish a correct diagnosis. Myocardial infarction can be divided into ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction. In the case of ST-segment elevation myocardial infarction thrombolytic therapy or percutaneous transluminal coronary angioplasty should be instituted as soon as possible. In patients without persistent ST-segment elevation biochemical markers of myocardial damage, especially troponin T and troponin I, are of major importance for risk stratification. Patients with elevated troponin levels should be treated with GPIIb/IIIa antagonists and early intervention.
MMW Fortschritte der Medizin 05/2002; 144(17):27-30.
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ABSTRACT: Intracoronary stents have been shown to reduce the rate of restenosis when compared with balloon angioplasty, but in-stent restenosis continues to be an important clinical problem. It was therefore the aim of this registry to identify procedural and angiographic predictors for the occurrence of in-stent restenosis. We analyzed 368 patients with 421 lesions who underwent coronary stent implantation between January 1998 and February 2000. Indications for the placement of a coronary stent were severe dissections (37%), suboptimal angiographic results (38%), restenotic lesions (20%), and graft lesions (4%). Angiographic follow-up was obtained in 270 patients (73%) with 293 lesions after 6 months. Clinical and angiographic variables were analyzed by univariate and multivariate models for the ability to predict the occurrence of in-stent restenosis, defined as a diameter stenosis >50%. In-stent restenosis was angiographically documented in 67 patients and 68 lesions (23%). Under all tested variables the reference luminal diameter before stent implantation (p = 0.006) and diabetes mellitus (p = 0.023) were identified as independent predictors for the occurrence of in-stent restenosis. The comparison of diabetic and nondiabetic patients according to vessel size revealed a 2 times higher rate of in-stent restenosis in small vessels (44% vs 23%, p = 0.002), whereas in vessels >3.0 mm the rate of in-stent restenosis was not significantly different between the 2 groups. In this registry, the clinical variable diabetes and the procedural variable reference vessel size were independent predictors for the occurrence of in-stent restenosis. In these patients, the rate of in-stent restenosis was as high as 45%.
The American Journal of Cardiology 09/2001; 88(3):243-7. · 3.37 Impact Factor
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DMW - Deutsche Medizinische Wochenschrift 05/2001; 126(14):405-7. · 0.53 Impact Factor
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ABSTRACT: The administration of GP IIb/IIIa antagonists has been shown to be effective in reducing myocardial infarction and cardial death when given before PTCA. This prospective study was performed to determine the efficacy of abciximab in a bail-out situation to manage threatened or acute vessel closure.
Acute or threatened vessel closure was observed in 104 (5.5%) out of 1903 consecutive patients treated with PTCA in our institution. Of the 104 patients 46 (44%) were treated for unstable angina (CCS IV). Abciximab was administered in bail-out situations in a dosage of 0.25 mg/kg given as a bolus, which was followed by an intravenous infusion of 10 micrograms/min over 12 hours. Repeat PTCA was performed shortly after the administration of the abciximab bolus. After the procedure, the sheath was left in place and control angiography was carried out 24 h later.
In 100 of the 104 patients TIMI flow III could be restored by abciximab therapy and RePTCA. In 4 patients an additional stent implantation was necessary due to persistent flow limitation. One day post PTCA, early follow-up angiography demonstrated patency of all vessels except two. In-hospital events occurred in 4 patients. Three of these patients underwent emergency CABG due to subacute vessel closure a few hours after PTCA and died during or directly after surgery. Follow-up after one year included clinical status and control angiography of the target vessel. During long-term follow-up, MACE occurred in 15 patients (2 MI, 8 CABG and 5 RePTCA).
The results of this prospective trial demonstrate the efficacy of abciximab therapy in bail-out situations occurring during or early after PTCA. The use of abciximab in bail-out situations appears clinically beneficial. Further studies have to compare the efficacy of this approach with prophylactic abciximab treatment.
Zeitschrift für Kardiologie 09/2000; 89(8):722-9. · 0.97 Impact Factor
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ABSTRACT: Vessel size adapted PTCA results in the use of larger balloons with an increased incidence of severe vascular dissections. The aim of our trial was (a) to evaluate the effect of severe dissections on the acute outcome and (b) to study the natural history of dissections after 1 year.
One hundred and seventy-eight patients with 195 lesions underwent vessel size adapted PTCA using intravascular ultrasound. Clinical and angiographic 1 year follow-up was obtained for all patients. Intravascular ultrasound was performed before PTCA to measure the external elastic membrane diameter at the lesion site so that the balloon size could be adopted (external elastic membrane-10%) and post-interventionally to determine the procedural success and the incidence of intracoronary dissections. Stent implantation was reduced to persistently flow limiting dissections (TIMI I, II). Dissections were detected by intravascular ultrasound in 128/195 (66%) lesions (by angiography in 111/195 [58%] lesions) and classified by intravascular ultrasound criteria into four groups: group I: no dissection (67 lesions [34%]), group II: mild dissections (21 lesions [11%]), group III: medium dissections (19 lesions [10%]) and group IV: severe dissections (88 lesions [45%]). Because of threatened vessel closure, GPIIb/IIIa antagonists were used in eight (4.5%) patients and a stent was implanted in two (1. 1%) patients. The cumulative event rate after 1 year was 12% and the global angiographic restenosis rate was 19%. The post-interventional evidence of severe dissections was associated with a decrease in clinical events during long-term follow up (group I: 13 events [19%] vs group IV: seven events [7%];P=0.03). This was also true for the occurrence of restenosis which was significantly lower in patients with severe dissections (group I: 19 [28%] lesions vs group IV:10 [11%] lesions;P=0.01).
According to the theory of 'therapeutic dissections', our data suggest that substantial dissections following PTCA, which do not diminish antegrade blood flow, do not lead to an increase in acute or long-term events. The natural history of vessel injury seems to provide favourable wound healing without increase of restenosis. Thus, stenting for treatment of large dissections without flow limitation does not seem to be mandatory.
European Heart Journal 02/2000; 21(2):137-45. · 10.48 Impact Factor
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ABSTRACT: The microtubule stabilizing compound paclitaxel has proved to have potent antiproliferative effects on smooth muscle cells both in vitro and in vivo. It induces cellular modifications that result in reduced proliferation, migration and signal transduction by shifting the cellular microtubule equilibrium towards assembly. We therefore reasoned that a visualization of the altered cytoskeleton could enable an evaluation of the drug effects following local drug delivery.
3 catheters - the porous balloon, the microporous balloon and the double balloon catheter - were chosen for this study representing the spectrum from passive to active, pressure-driven delivery. After the induction of a defined plaque in the right carotid arteries of 40 New Zealand rabbits by electrical stimulation, 32 animals underwent balloon dilatation and 8 animals served as pre-interventional control group with electrostimulation only. In 24 animals (n = 8 in each group) subsequent local paclitaxel delivery (10 micromol/L) was performed. 8 animals served as control with angioplasty only. Vessels were excised 1 week following intervention. Immunohistochemistry with antibodies against bromodeoxyuridine, alpha-actin, macrophages, von Willebrand factor and alpha-tubulin was performed. Cytoskeletal changes were analyzed by electron microscopy. Tubulin staining and electron microscopy revealed changes with distinct staining patterns for the different catheters. Specific catheter-induced injuries could be identified for the porous and double balloon catheter. Intimal proliferation, percentage of macrophages and extent of injury favor the double balloon catheter for local paclitaxel delivery.
The alterations of the cytoskeleton induced by paclitaxel allowed for the detection of drug action by staining of tubulin and electron microscopy. This enables an evaluation of transfer, distribution and drug effects directly in the vasculature without marker substances. The double balloon catheter appears to be best suited for local paclitaxel therapy.
Archiv für Kreislaufforschung 01/2000; 94(6):454-63. · 7.35 Impact Factor
