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1.
Circulation ; 123(9): 951-60, 2011 Mar 08.
Article in English | MEDLINE | ID: mdl-21339482

ABSTRACT

BACKGROUND: Permanent pacemaker (PPM) requirement is a recognized complication of transcatheter aortic valve implantation. We assessed the UK incidence of permanent pacing within 30 days of CoreValve implantation and formulated an anatomic and electrophysiological model. METHODS AND RESULTS: Data from 270 patients at 10 centers in the United Kingdom were examined. Twenty-five patients (8%) had preexisting PPMs; 2 patients had incomplete data. The remaining 243 were 81.3±6.7 years of age; 50.6% were male. QRS duration increased from 105±23 to 135±29 milliseconds (P<0.01). Left bundle-branch block incidence was 13% at baseline and 61% after the procedure (P<0.001). Eighty-one patients (33.3%) required a PPM within 30 days. Rates of pacing according to preexisting ECG abnormalities were as follows: right bundle-branch block, 65.2%; left bundle-branch block, 43.75%; normal QRS, 27.6%. Among patients who required PPM implantation, the median time to insertion was 4.0 days (interquartile range, 2.0 to 7.75 days). Multivariable analysis revealed that periprocedural atrioventricular block (odds ratio, 6.29; 95% confidence interval, 3.55 to 11.15), balloon predilatation (odds ratio, 2.68; 95% confidence interval, 2.00 to 3.47), use of the larger (29 mm) CoreValve prosthesis (odds ratio, 2.50; 95% confidence interval, 1.22 to 5.11), interventricular septum diameter (odds ratio, 1.18; 95% confidence interval, 1.10 to 3.06), and prolonged QRS duration (odds ratio, 3.45; 95% confidence interval, 1.61 to 7.40) were independently associated with the need for PPM. CONCLUSION: One third of patients undergoing a CoreValve transcatheter aortic valve implantation procedure require a PPM within 30 days. Periprocedural atrioventricular block, balloon predilatation, use of the larger CoreValve prosthesis, increased interventricular septum diameter and prolonged QRS duration were associated with the need for PPM.


Subject(s)
Aortic Valve , Cardiac Catheterization/trends , Cardiac Pacing, Artificial/trends , Heart Valve Prosthesis Implantation/trends , Pacemaker, Artificial/trends , Aged , Aged, 80 and over , Aortic Valve/pathology , Aortic Valve Stenosis/physiopathology , Aortic Valve Stenosis/therapy , Cardiac Catheterization/methods , Cardiac Pacing, Artificial/methods , Female , Heart Valve Prosthesis Implantation/instrumentation , Heart Valve Prosthesis Implantation/methods , Humans , Incidence , Male , Retrospective Studies , United Kingdom
2.
Int J Cardiol ; 321: 24-29, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-32800911

ABSTRACT

OBJECTIVE: We aimed to assess the use of enhanced stent visualisation (ESV) on outcomes, after PCI with overlapping stents, specifically using CLEARstent technology. BACKGROUND: Stent underexpansion and overlap are both significant risk factors for restenosis and stent thrombosis. Enhanced stent visualisation (e.g. CLEARstent) systems could provide important data to reduce under-expansion and stent overlap. METHODS: This was a cohort study based on this institution's percutaneous coronary intervention (PCI) registry. A total of 2614 patients who had PCI for stable angina or acute coronary syndromes (ACS, excluding cardiogenic shock) with overlapping 2nd generation drug eluting stents (DES) in the same vessel between May 2015 and January 2018 were included in the analysis. Patients were divided into ESV (n = 1354) and no ESV guided intervention (n = 1260). The primary end-point was major adverse cardiovascular events (MACE: target vessel revascularisation, target vessel myocardial infarction and all-cause mortality) recorded at a median follow up of 2.4 years. RESULTS: Groups were comparable for patient characteristics (age, diabetes mellitus, ACS presentation). A significant difference in MACE was observed between patients who underwent ESV-guided PCI (9.5%) compared with patients who underwent Standard PCI (14.4%, p = .018). This difference was mainly driven by reduced rates of target vessel revascularisation and recurrent myocardial infarction. Overall this difference persisted after multivariate Cox analysis (HR 0.86, 95% CI: 0.73-0.98) and propensity matching (HR = 0.88, 95% CI: 0.69-0.99). CONCLUSION: We suggest that routine clinical use of ESV technology during PCI can be useful, and is associated with better medium-term angiographic and clinical outcomes. Further study is required to build on this promising signal.


Subject(s)
Percutaneous Coronary Intervention , Angiography , Cohort Studies , Coronary Angiography , Humans , Percutaneous Coronary Intervention/adverse effects , Risk Factors , Stents , Treatment Outcome
3.
Circulation ; 104(4): 480-5, 2001 Jul 24.
Article in English | MEDLINE | ID: mdl-11468213

ABSTRACT

BACKGROUND: Intraluminal beta-irradiation has been shown to decrease neointimal proliferation after angioplasty in experimental models. The purpose of this study was to test the technical feasibility and biological effects of (186)Re-labeled stents. METHODS AND RESULTS: Thirty-four New Zealand White rabbits were fed a 0.5% cholesterol diet before balloon angioplasty and insertion of Palmaz stents in the infrarenal aorta. The animals were killed 7 weeks after stent implantation. Two of 34 animals died prematurely (aortic leak, pneumonia). Control stents (n=7) were compared with (186)Re stents (2.6 MBq [n=6], 8.1 MBq [n=5], 16.0 MBq [n=6], and 25.3 MBq [n=8]). Stent application was successful in all cases. No thrombus occlusion was observed. After 7 weeks, neointima formation was 2.2+/-0.2 mm(2) in the control group. In the treatment groups, a dose-dependent neointima reduction was detectable (0.5+/-0.5 mm(2) [2.6 MBq], 0.4+/-0.4 mm(2) [8.1 MBq], and 0 mm(2) [16.0 MBq, 25.3 MBq]). No induction of neointimal formation was observed at the edges of the stents. Radiation resulted in delayed reendothelialization. CONCLUSIONS: (186)Re stents were capable of reducing neointima formation in a dose-dependent fashion. (186)Re stents did not cause late thrombosis or neointimal induction at the stent margins in the observation period of 7 weeks.


Subject(s)
Arterial Occlusive Diseases/prevention & control , Radioisotopes/therapeutic use , Rhenium/therapeutic use , Stents , Animals , Aorta, Abdominal/pathology , Aorta, Abdominal/radiation effects , Aorta, Abdominal/surgery , Brachytherapy/methods , Disease Models, Animal , Dose-Response Relationship, Radiation , Endothelium, Vascular/pathology , Endothelium, Vascular/radiation effects , Fibrin/metabolism , Half-Life , Male , Rabbits , Time Factors , Tunica Intima/metabolism , Tunica Intima/pathology , Tunica Intima/radiation effects , Tunica Media/metabolism , Tunica Media/pathology , Tunica Media/radiation effects
4.
J Am Coll Cardiol ; 35(7): 1969-76, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10841250

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate the potential of paclitaxel to prevent restenosis in vivo. BACKGROUND: Paclitaxel (Taxol) is a microtubule-stabilizing compound with potent antitumor activity. It influences the cytoskeleton equilibrium by increasing the assembly of altered microtubules, thereby inducing cellular modifications that result in reduced proliferation, migration and signal transduction. METHODS: Before the in vivo study, delivery efficiency was determined with radiolabeled paclitaxel in porcine hearts. After induction of a defined plaque in the right carotid arteries of 76 New Zealand rabbits by electrical stimulation, 27 animals underwent balloon dilation and subsequent local paclitaxel delivery (10 ml, 10 micromol/liter) with a double-balloon catheter. Twenty-nine animals served as control with angioplasty only, 10 animals underwent local delivery of vehicle only (0.9% NaCl solution) and 10 animals were solely electrostimulated. Vessels were excised one, four, and eight weeks after intervention. RESULTS: The extent of stenosis in paclitaxel-treated animals was significantly reduced compared with balloon-dilated control animals (p = 0.0012, one, four and eight weeks after intervention: 14.6%, 24.6% and 20.5%, vs. 24.9%, 33.8% and 43.1%, respectively). Marked vessel enlargement compared with balloon-dilated control animals could be observed (p = 0.0001, total vessel area after one, four and eight weeks: paclitaxel group: 1.983, 1.700 and 1.602 mm2, control: 1.071, 1.338 and 1.206 mm2, respectively). Tubulin staining and electron microscopy revealed changes in microtubule assembly, which were limited to the intimal area. Vasocontractile function after paclitaxel treatment showed major impairment. CONCLUSIONS: Local delivery of paclitaxel resulted in reduced neointimal stenosis and enlargement in vessel size. Both these effects contribute to a preservation of vessel shape and are likely to be caused by a structural alteration of the cytoskeleton.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Paclitaxel/administration & dosage , Vascular Diseases/pathology , Vascular Diseases/prevention & control , Animals , Constriction, Pathologic/pathology , Constriction, Pathologic/prevention & control , Rabbits , Recurrence , Swine
5.
J Am Coll Cardiol ; 23(6): 1305-13, 1994 May.
Article in English | MEDLINE | ID: mdl-8176087

ABSTRACT

OBJECTIVES: The aim of this study was to document and analyze the incidence and consequences of complications of excimer laser coronary angioplasty. BACKGROUND: Excimer laser coronary angioplasty has been reported to be a safe and feasible alternative or adjunct to conventional balloon angioplasty, but serious and unique complications have been observed. METHODS: Data on 1,595 interventions of excimer laser coronary angioplasty in 1,521 patients were analyzed, using a merged data base from the U.S. and European Percutaneous Excimer Laser Coronary Angioplasty (PELCA) registries. RESULTS: Procedural success was achieved in 89.3% of interventions. Stand-alone laser angioplasty was performed in 17.8% of interventions. Complications included dissection (22.0%), vasospasm (6.1%), filling defects (4.8%), abrupt reclosure (6.1%), embolization (2.3%), perforation (2.4%), arrhythmia (0.7%) and aneurysm formation (0.3%). Major complications were non-Q wave myocardial infarction (2.3%), Q wave myocardial infarction (1.0%), coronary artery bypass grafting (3.1%) and death (0.7%). Logistic regression analysis revealed correlation between dissections and the use of larger catheter size (p = 0.0005), high energy per pulse levels (p = 0.0001 for native vessels), lesion length > 10 mm (p = 0.001) and presence of a side branch (p = 0.01). The incidence of perforations was higher in women (p = 0.004), in treatment of total occlusions (p = 0.02) and in the presence of a side branch (p = 0.03). Fatal complications were correlated with patients with multivessel disease (p < 0.0001), patients with acute myocardial infarction (p = 0.0009) and older patients (> 70 years old, p = 0.004). The incidence of major complications decreased after performance of 50 laser angioplasty procedures at one institution (p = 0.02). CONCLUSIONS: This analysis defines both the learning curve and the profile of complications for excimer laser angioplasty and provides insight into the selection of appropriate patients and proper performance of the procedure.


Subject(s)
Angioplasty, Balloon, Coronary/adverse effects , Angioplasty, Balloon, Laser-Assisted/adverse effects , Postoperative Complications/epidemiology , Acute Disease , Adult , Aged , Aged, 80 and over , Angioplasty, Balloon, Coronary/statistics & numerical data , Angioplasty, Balloon, Laser-Assisted/statistics & numerical data , Chi-Square Distribution , Coronary Disease/complications , Coronary Disease/epidemiology , Coronary Disease/surgery , Europe/epidemiology , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Multivariate Analysis , Registries/statistics & numerical data , United States/epidemiology
6.
J Am Coll Cardiol ; 37(5): 1430-5, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11300457

ABSTRACT

OBJECTIVES: The aim of the present study was to evaluate the accuracy in determining coronary lesion configuration by multislice computed tomography (MSCT). The results were compared with the findings of intracoronary ultrasound (ICUS). BACKGROUND: The risk of acute coronary syndromes caused by plaque disruption and thrombosis depends on plaque composition rather than stenosis severity. Thus, the reliable noninvasive assessment of plaque configuration would constitute an important step forward for risk stratification in patients with known or suspected coronary artery disease. Just recently, MSCT scanners became available for general purpose scanning. Due to improved spatial and temporal resolution, this new technology holds promise to allow for differentiation of coronary lesion configuration. METHODS: The ICUS and MSCT scans (Somatom Volume Zoom, Siemens, Forchheim, Germany) were performed in 15 patients. Plaque composition was analyzed according to ICUS (plaque echogenity: soft, intermediate, calcified) and MSCT criteria (plaque density expressed by Hounsfield units [HU]). RESULTS: Thirty-four plaques were analyzed. With ICUS, the plaques were classified as soft (n = 12), intermediate (n = 5) and calcified (n = 17). Using MSCT, soft plaques had a density of 14 +/- 26 HU (range -42 to +47 HU), intermediate plaques of 91 +/- 21 HU (61 to 112 HU) and calcified plaques of 419 +/- 194 HU (126 to 736 HU). Nonparametric Kruskal-Wallis test revealed a significant difference of plaque density among the three groups (p < 0.0001). CONCLUSIONS: Our results indicate that coronary lesion configuration might be correctly differentiated by MSCT. Since also rupture-prone soft plaques can be detected by MSCT, this noninvasive method might become an important diagnostic tool for risk stratification in the near future.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Tomography, X-Ray Computed , Adult , Aged , Angina Pectoris/diagnostic imaging , Angina Pectoris/therapy , Angioplasty, Balloon, Coronary , Calcinosis/diagnostic imaging , Calcinosis/therapy , Coronary Artery Disease/therapy , Female , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/therapy , Risk Assessment , Sensitivity and Specificity , Ultrasonography, Interventional
7.
J Am Coll Cardiol ; 22(3): 777-82, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8354812

ABSTRACT

OBJECTIVES: This exercise study assessed the relation between valvular resistance and flow in patients with mitral stenosis. BACKGROUND: Valvular resistance has been proposed as an alternative measure of stenotic valvular lesions, which is speculated to remain stable under changing hemodynamic conditions. METHODS: In 35 of 40 patients with pure or predominant mitral stenosis, continuous wave Doppler measurements of the mitral stenotic jet were possible at rest and during supine bicycle ergometry. Simultaneously, transvalvular flow was assessed by thermodilution technique. For calculation of valvular resistance, the mean mitral valve pressure gradient was determined according to the simplified Bernoulli equation and divided by transvalvular flow. Additionally, effective mitral valve area was calculated according to the continuity equation method, dividing flow by the mean diastolic flow velocity. RESULTS: Valvular resistance was 65 +/- 32 dynes.s.cm-5 at rest and increased to 82 +/- 43 dynes.s.cm-5 at 25 W (p < 0.001). The most prominent increase in valvular resistance (rest to 25 W 63 +/- 28 to 95 +/- 48 dynes.s.cm-5, p < 0.001) was found in those patients who had no or only a moderate (< 20%) change in effective mitral valve area. In contrast, valvular resistance remained constant (67 +/- 36 vs. 70 +/- 32 dynes.s.cm-5) in patients with a significant (> or = 20%) increase in mitral valve area with exercise. CONCLUSIONS: In patients with mitral stenosis, the exercise-induced changes in valvular resistance are heterogeneous. This is the result of the variable response of mitral valve area to an increase in flow. In the individual patient, mitral valve area can significantly increase, a factor that has to be taken into account when interpreting the hemodynamic relevance of the obstruction. Calculated valvular resistance is flow dependent and has no advantage over valve area calculations for quantifying mitral stenosis.


Subject(s)
Exercise/physiology , Mitral Valve Stenosis/physiopathology , Mitral Valve/physiopathology , Adult , Aged , Blood Flow Velocity , Cardiac Catheterization , Diastole , Echocardiography, Doppler , Exercise Test , Female , Humans , Male , Mathematics , Middle Aged , Mitral Valve/diagnostic imaging , Mitral Valve Stenosis/diagnostic imaging
8.
Cardiovasc Res ; 38(3): 751-62, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9747444

ABSTRACT

OBJECTIVE: Recent investigations revealed the importance of endothelial cell integrity and function in the pathogenesis of restenosis after angioplasty. Agents which stimulate reendothelialization may prevent restenosis after interventional procedures. The results of in vitro studies suggested that heparin and low molecular weight heparin administration may enhance the recovery of the endothelium. In this study the extent of endothelial denudation and the occurrence and time course of endothelial regeneration after experimental balloon angioplasty followed by subcutaneous or local delivery of low molecular weight heparin was investigated. METHODS: A total of 102 rabbits were included in the study. An atheromatous plaque was induced by electrical stimulation in the right carotid artery of the animals. All animals underwent balloon angioplasty. Thirty-two rabbits received no further medical treatment. Twenty-five rabbits received subcutaneous low molecular weight heparin reviparin (400 anti-Xa-units/day) during the following 7 days. In 25 animals the dilated arterial segments were treated locally with reviparin (1500 anti-Xa-units/4 ml, 2 atm) using a porous balloon (2.5 mm, 35 holes, diameter 75 microns). Twenty animals served as control group without intervention. The vessels were excised 3, 7, 14, 28 and 56 days following intervention. Sections were stained with an antibody against von Willebrand factor and PECAM 1 to confirm the endothelial origin of the lining cells. After bromodeoxyuridine labeling, the extent of proliferation was determined by using a monoclonal antibody. In addition, morphometric analysis of the intimal and medial area was performed. RESULTS: Three days after balloon angioplasty histomorphological analysis showed a reduction of about 60% of the preinterventional endothelial cell number in all three groups. Already one week after intervention there was a significantly higher number of endothelial cells in both groups of low molecular weight heparin treated animals compared to the untreated group (s.c. group 144 +/- 33, local group 142 +/- 32 versus untreated 79 +/- 17 endothelial cells, p < or = 0.05). This significant difference was maintained during the following four weeks and demonstrated a 2-fold increase in endothelial proliferation in the heparin treated animals compared with the untreated group. In addition, immunohistological examination showed a significant decrease in smooth muscle cell proliferation in the s.c. and local reviparin treated animals and a subsequent reduction of intimal thickening. CONCLUSION: Local delivery of low molecular weight heparin promotes reendothelialization and contributes to the inhibition of smooth muscle cell proliferation.


Subject(s)
Angioplasty, Balloon/adverse effects , Endothelium, Vascular/injuries , Fibrinolytic Agents/administration & dosage , Heparin, Low-Molecular-Weight/administration & dosage , Regeneration , Administration, Cutaneous , Administration, Topical , Animals , Arteriosclerosis/pathology , Arteriosclerosis/therapy , Carotid Arteries/pathology , Disease Models, Animal , Endothelium, Vascular/drug effects , Endothelium, Vascular/pathology , Fibrinolytic Agents/therapeutic use , Heparin, Low-Molecular-Weight/therapeutic use , Histological Techniques , Image Processing, Computer-Assisted , Male , Microscopy, Electron, Scanning , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/pathology , Rabbits , Stimulation, Chemical
9.
Am J Cardiol ; 68(13): 1310-5, 1991 Nov 15.
Article in English | MEDLINE | ID: mdl-1951118

ABSTRACT

The treatment of complex coronary lesions with conventional balloon angioplasty is associated with a reduced success rate and an increased incidence of complications. To evaluate the influence of lesion morphology on the outcome of coronary excimer laser angioplasty, morphologic parameters of 148 target lesions in 147 consecutive patients were determined. Morphologic analysis included target vessel, involved vessel segment, vessel diameter, minimal lumen diameter, length of the lesion, single discrete (concentric/eccentric) or complex lesions (occlusions, bifurcational, tandem or long segmental lesions), American College of Cardiology/American Heart Association Task Force classification, lesion location in curved or straight vessel segments, prestenotic vessel tortuosity and the direction of the laser approach in curved vessels with eccentric lesions. Failure of laser angioplasty occurred in 17 patients because of failed guidewire placement (n = 8), catheter placement (n = 6), or inability to pass the lesion with the laser catheter (n = 3). Successful stand-alone laser angioplasty was achieved in 68 procedures. In 63 interventions additional balloon angioplasty was necessary (n = 60) or stand-alone laser angioplasty was not successful (n = 3). The frequency of complex lesions, particularly total occlusions (p less than 0.001) and prestenotic vessel tortuosity (p = 0.002) was significantly increased in the group with failed laser attempts. Statistical analysis of the morphologic parameters in successful stand-alone laser interventions compared with combined or unsuccessful interventions revealed no significant difference. These data suggest that failure of laser angioplasty occurs because of low catheter flexibility and the need for guidewire support in treating totally occluded vessels.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Angioplasty, Laser , Coronary Disease/surgery , Coronary Vessels/pathology , Angioplasty, Laser/instrumentation , Constriction, Pathologic/epidemiology , Constriction, Pathologic/pathology , Constriction, Pathologic/surgery , Coronary Disease/epidemiology , Coronary Disease/pathology , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
10.
Am J Cardiol ; 83(6): 875-9, 1999 Mar 15.
Article in English | MEDLINE | ID: mdl-10190402

ABSTRACT

Restenosis following percutaneous transluminal coronary angioplasty (PTCA) remains a serious problem in interventional cardiology. Recent trials using stent implantation have proposed a reduction in restenosis, presumably due to a higher initial luminal gain. This study was conducted to evaluate if the short- and long-term results following conventional PTCA may be favorable, if balloon dilation was performed according to measurements gained by intravascular ultrasound (IVUS) (vessel size adapted PTCA). The use of intracoronary stents might be omitted if comparable long-term results could be achieved by this modified technique of balloon angioplasty. This unicenter and nonrandomized pilot trial was initiated in January 1995 with 252 patients who had 271 lesions. IVUS was performed before and after intervention to determine the external elastic membrane (EEM) diameter at the lesion site. The balloon catheter was sized according to the EEM diameter measured by IVUS (EEM 10%). The mean balloon diameter was 4.1 +/- 0.5 mm, the dilation time 130 +/- 60 seconds with a balloon pressure of 7.0 +/- 2.0 atm. Clinical acute and 1-year long-term follow-up were obtained for all patients and follow-up angiography in 71% of patients. Acute events occurred postinterventionally in 5 patients (2%). The cumulative event rate during long-term follow-up was 14%. The angiographic restenosis rate (diameter stenosis >50%) after 1 year was 19%. Vessel size adapted PTCA using IVUS led to favorable acute and long-term results with a low restenosis rate and a low 1-year clinical event rate. Despite dissections that occur frequently using large balloon sizes, an increased rate of major complications did not occur, indicating a safe procedure and substantiating the philosophy of "therapeutic dissections." The results need to be verified in a randomized trial.


Subject(s)
Angioplasty, Balloon, Coronary , Coronary Vessels/diagnostic imaging , Ultrasonography, Interventional , Angioplasty, Balloon, Coronary/adverse effects , Angioplasty, Balloon, Coronary/methods , Coronary Angiography , Coronary Disease/diagnostic imaging , Coronary Disease/therapy , Female , Humans , Male , Middle Aged , Pilot Projects , Recurrence
11.
Am J Cardiol ; 86(3): 263-8, 2000 Aug 01.
Article in English | MEDLINE | ID: mdl-10922430

ABSTRACT

This study was undertaken to compare the effects of reteplase and alteplase regimens on hemostasis and fibrinolysis in acute myocardial infarction (AMI). Thrombolytic treatment in patients with AMI is hampered by paradoxical procoagulant effects that favor early reocclusion. In vivo data comparing this effect and the fibrin specificity of double-bolus reteplase and front-loaded alteplase regimens are not available. In a prospective, randomized study, 50 patients with AMI were either treated with double bolus (10 + 10 U) reteplase or with front-loaded alteplase (up to 100 mg) within 6 hours of symptom onset. Thirty apparently healthy persons served as controls. Molecular markers of coagulation and fibrinolysis were serially examined for up to 5 days. Paradoxical thrombin activation at 3 hours after initiation of therapy was comparable between reteplase and alteplase. Reteplase (65 +/- 5 U/L) and alteplase (72 +/- 8 U/L) caused significantly elevated kallikrein activity at 3 hours after adminstration (p <0.01 vs controls 30 +/- 1 U/L). Fibrin specificity was less for reteplase (p <0.05) with a decrease in fibrinogen at 3 hours to 122 +/- 27 mg/dl versus 224 +/- 28 mg/dl for alteplase (p <0.01 and p <0.05 vs controls). D-Dimer levels at 3 hours were higher (p <0.05) after reteplase (5,459 +/- 611 ng/ml) versus alteplase (3,445 +/- 679 ng/ml) (both p <0.01 vs controls 243 +/- 17 ng/ml). Plasmin generation (plasmin-antiplasmin complexes) was significantly (p <0.01) increased at 3 hours with both regimens to 27,079 +/- 3,964 microg/L (reteplase) and 19,522 +/- 2,381 microg/L (alteplase). The data from 3 hours after start of thrombolytic therapy proved less marked fibrin specificity of the reteplase regimen (in vivo) compared with front-loaded alteplase. Both regimens have a moderate procoagulant effect without differences in activation of the kallikrein system.


Subject(s)
Fibrin/drug effects , Fibrinolysin/metabolism , Fibrinolysis/drug effects , Fibrinolytic Agents/administration & dosage , Kallikreins/drug effects , Myocardial Infarction/drug therapy , Thrombolytic Therapy , Tissue Plasminogen Activator/administration & dosage , Adult , Aged , Aged, 80 and over , Antithrombin III/drug effects , Antithrombin III/metabolism , Dose-Response Relationship, Drug , Drug Administration Schedule , Drug Therapy, Combination , Female , Fibrin/metabolism , Fibrinolytic Agents/adverse effects , Hemostasis/drug effects , Humans , Kallikreins/metabolism , Male , Middle Aged , Myocardial Infarction/blood , Peptide Hydrolases/drug effects , Peptide Hydrolases/metabolism , Prospective Studies , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Recurrence , Thrombin/metabolism , Tissue Plasminogen Activator/adverse effects
12.
Invest Radiol ; 36(5): 245-9, 2001 May.
Article in English | MEDLINE | ID: mdl-11323511

ABSTRACT

RATIONALE AND OBJECTIVES: Several radiopharmaceuticals were administered through a porous balloon catheter to compare the absolute amount deposited and the retention in the vessel wall. The reported efficiency of local drug delivery ranges from 0.001% to 0.1%, with poor retention after 24 hours. METHODS: An endothelin derivative (n = 6), pertechnetate (n = 6), hexamethylpropylene amineoxime (HMPAO) (n = 5), ethyl cysteinate dimer (ECD) (n = 5), and tin colloid (n = 5) were labeled with 185 MBq/mL 99m-technetium. After balloon denudation of the infrarenal aorta in 27 New Zealand White rabbits, 100 microL of each agent was administered through a porous balloon at a pressure of 4 bar. Dynamic and static whole-body scintigrams were obtained for 24 hours. The infrarenal aorta was excised and the activity calculated in a gamma counter. RESULTS: Apart from their retention in the region of local administration, the radiopharmaceuticals showed different distribution patterns. The highest regional tracer retention was observed with HMPAO. After administration of HMPAO, a significant difference between regional (vessel wall plus surrounding tissue: 14.5% of injected dose [ID]/24 hours) and local (vessel wall: 1.8% ID/24 hours) delivery was found. In contrast, ECD was eliminated quickly (local retention after 24 hours = 0% ID). The retention efficiencies were HMPAO > endothelin derivative > tin colloid > pertechnetate > ECD. CONCLUSIONS: The different physicochemical and pharmacokinetic properties of radiopharmaceuticals resulted in different delivery efficiencies after local application.


Subject(s)
Arteriosclerosis/prevention & control , Radiopharmaceuticals/pharmacokinetics , Animals , Catheterization , Injections, Intra-Arterial , Male , Rabbits , Radiopharmaceuticals/administration & dosage , Recurrence
13.
Heart ; 80(4): 349-54, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9875110

ABSTRACT

OBJECTIVE: Flow associated dilatation (FAD%) and intimal media thickness are established markers of early atherosclerosis. This study aimed to compare the ability of the non-invasive measurements FAD% and intimal media thickness to predict coronary artery disease. METHODS: FAD% and intimal media thickness were determined using high resolution ultrasound in 122 patients with clinically suspected coronary artery disease before coronary angiography. Results are given as mean (SD). RESULTS: Patients with coronary artery disease had reduced FAD% compared with those with angiographically normal coronary vessels (3.7 (4.1) v 7.0 (3.5)%, p < 0.001), whereas intimal media thickness tended to be increased in patients with coronary artery disease (0.58 (0.35) v 0.47 (0.11)mm, p = 0.054). There was a negative correlation between FAD% and intimal media thickness (R = -0.317, p = 0.0004). Receiver operating characteristic analysis showed that FAD% < or = 4.5% predicted coronary artery disease with a sensitivity of 0.71 (95% confidence interval 0.61 to 0.80) and a specificity of 0.81 (0.58 to 0.95). In contrast, intimal media thickness showed a positive correlation with the extent of coronary artery disease (number of vessels with a lesion > or = 50%) (R = 0.324, p = 0.0003), without a clear cut off point. CONCLUSIONS: In patients with clinically suspected coronary artery disease, FAD% discriminates between the presence or absence of coronary artery disease, whereas intimal media thickness is associated more with the extent of coronary artery disease.


Subject(s)
Coronary Disease/diagnostic imaging , Endothelium, Vascular/diagnostic imaging , Tunica Intima/pathology , Adult , Aged , Brachial Artery/diagnostic imaging , Carotid Artery, Common/diagnostic imaging , Coronary Angiography , Coronary Disease/pathology , Coronary Disease/physiopathology , Endothelium, Vascular/physiopathology , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Ultrasonography , Vasodilation
14.
Int J Cardiol ; 76(2-3): 219-25, 2000.
Article in English | MEDLINE | ID: mdl-11104877

ABSTRACT

BACKGROUND: The non-invasive determination of the endothelial dysfunction (ED) of the brachial artery is a widely used method in clinical research. It remained, however, unclear, whether the test-results are influenced by the anatomical vessel size, the patients age, body mass index (BMI) or gender. METHODS: The flow-mediated vasodilatation (FMD%) of the brachial artery was determined in 122 consecutive (88 male, 34 female) patients. FMD% was measured using high resolution ultrasound (13 Mhz) at rest, during reactive hyperaemia and after the sublingual administration of glycerolnitrate (GTN%). RESULTS: Lumen diameters at rest varied from 2.48 mm to 6.33 mm (4.46+/-0.74 mm). The extent of FMD% as well as of GTN% showed an inverse correlation to the resting lumen diameters (r=-0.33, P<0.001/r=-0.51, P<0.001). This correlation was even more distinct in females (females: FMD% r=-0.54, P<0.001; GTN% r=-0.64, P<0.001 vs. males: FMD% -0.23, P<0.001; GTN% -0.59, P<0. 001). No significant influence of age (61+/-9 years, FMD%: r=-0.04, P=0.68, GTN%: r=-0.18, P=0.05) and BMI (27.03+/-3.43 kg/m(2), FMD%: r=0.16, P=0.08, GTN%: r=0.09, P=0.3) on the test results were found. CONCLUSIONS: FMD% was found to be rather independent of age or BMI. The anatomical vessel size had an influence on the test results, which was more obvious in female patients. Our data indicate the necessity of further methodological studies, in larger, community-based populations. In particular, it needs to be clarified, whether vessel size or even gender-specific correction factors are required when using this technique in routine clinical practice.


Subject(s)
Brachial Artery/physiopathology , Adult , Age Factors , Aged , Blood Flow Velocity , Body Mass Index , Brachial Artery/diagnostic imaging , Brachial Artery/drug effects , Chi-Square Distribution , Coronary Disease/physiopathology , Endothelium, Vascular/physiopathology , Female , Humans , Male , Middle Aged , Prospective Studies , Regression Analysis , Sex Factors , Statistics, Nonparametric , Ultrasonography , Vasodilation/drug effects , Vasodilation/physiology
15.
Rofo ; 160(2): 125-31, 1994 Feb.
Article in German | MEDLINE | ID: mdl-8312508

ABSTRACT

In 134 patients, 21 iliac, 91 femoropopliteal and 22 crural arterial occlusions were treated by percutaneous laser-assisted angioplasty and in 32 patients femoropopliteal occlusions by conventional balloon angioplasty. Laser angioplasty could be performed in 126 patients following initial guide wire recanalisation using 9.7 and 4.5-F multifiber catheters, respectively. In 72 patients a 308-nm excimer laser and in 54 patients a 504-nm pulsed day laser was used. Luminal opening by laser angioplasty was obtained in 102 of 126 (81%) procedures (9 incomplete catheter passages, 15 persistent occlusions). 95% of iliac, 90% of femoropopliteal and 77% of crural recanalizations including supplemental balloon dilatations (n = 105) and stent implantations (n = 24) succeeded technically. Clinical success rates at 1 (2) years after angioplasty were 95% (89%) for iliac, 66% (63%) for femoropopliteal and 57% (50%) for crural treatments. Technical and clinical results of laser-assisted femoropopliteal recanalizations showed no significant differences in comparison to the results of conventional balloon angioplasty. The use of pulsed lasers for the treatment of peripheral arterial occlusive disease would require further technical improvements.


Subject(s)
Angioplasty, Laser/methods , Arterial Occlusive Diseases/therapy , Adult , Aged , Aged, 80 and over , Angiography , Angioplasty, Balloon , Female , Femoral Artery , Humans , Iliac Artery , Male , Middle Aged , Popliteal Artery , Stents
16.
J Invasive Cardiol ; 13(6): 456-9, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11385170

ABSTRACT

PURPOSE: To assess the feasibility and initial clinical results of Closer (Perclose, Redwood City, California), a new device for percutaneous suture-mediated closure of arterial puncture sites. METHODS: Vascular interventions were performed using 6 and 7 French sheaths in 22 consecutive patients. All patients underwent suture-mediated percutaneous closure with the new device. Patients were followed by physical examination the day after the procedure. RESULTS: Immediate hemostasis was achieved in 20/22 patients (91%). In 3 out of 5 antegrade closures, only one suture was captured. In two cases, this was managed by reinsertion of a second device. In another patient, hemostasis was not achieved by the device due to knot entrapment. No major complications were observed. The overall rate of minor complications was 9% (2/22) due to hematomas without the need for blood transfusions. CONCLUSION: Percutaneous suture with this new device is an acceptably safe and effective method to achieve immediate hemostasis of the arterial access site after interventional procedures with minimized manipulation of the puncture track.


Subject(s)
Arteries/surgery , Needles/statistics & numerical data , Punctures/instrumentation , Sutures , Adult , Aged , Aged, 80 and over , Equipment Design , Female , Hemostasis/physiology , Humans , Male , Middle Aged
17.
Med Klin (Munich) ; 95(3): 130-5, 2000 Mar 15.
Article in German | MEDLINE | ID: mdl-10771558

ABSTRACT

BACKGROUND: Quality control becomes increasingly important in interventional cardiology. Since in most health care systems, clinical treatment of patients who underwent percutaneous transluminal coronary angioplasty (PTCA) is left to general practitioners, important information on the clinical long-term outcome is lost for the cardiologic centers. Aim of this study was to evaluate the clinical status of these patients 4 years after treatment with a PTCA at our institution. PATIENTS AND METHODS: Inclusion criterion was the treatment with a PTCA within July 1, 1989 to June 30, 1991 (549 patients). A questionnaire was sent to all patients (45 +/- 7 months after PTCA). Four time-points were defined: before PTCA (T1), directly after PTCA (T2), 3 months after PTCA (T3) and actual status (T4). RESULTS: Questionnaires of 500/549 (91.1%) patients could be analyzed. One-hundred and fifteen patients (23%) had to undergo reinterventions: 69 (13.8%) had a re-PTCA and 46 (9.2%) patients an operative revascularization. At T4, 11.2% patients still had disturbing angina. Within the study period 35 patients (7%) died. Two-hundred and nineteen patients attended a rehabilitation institution. At T4, the amount of patients with little angina was not different comparing patients with/without the attendance of a rehabilitation institution (60.7% vs 66.4% p = 0.29). The rate of new pensioners after PTCA (n = 114 [22.8%]) was higher in the group of patients who attended a rehabilitation (68 patients [13.6%] with vs 48 patients [9.2%] without attendance, p = 0.0036). The attendance of a rehabilitation institution, however, had positive effects on changes of the life style and eating habits. CONCLUSIONS: This retrospective inquiry was found to be a useful tool (response rate 91.1%) for quality control in interventional cardiology. Important information concerning the quality of the interventions (low reintervention rate) and the long-term outcome of our patients (low rate with severe angina at T4) could be acquired.


Subject(s)
Angina Pectoris/psychology , Angioplasty, Balloon, Coronary/adverse effects , Coronary Disease/psychology , Coronary Disease/therapy , Quality of Life/psychology , Aged , Angina Pectoris/etiology , Coronary Disease/complications , Coronary Disease/mortality , Coronary Disease/rehabilitation , Follow-Up Studies , Germany , Humans , Middle Aged , Outcome Assessment, Health Care , Population Surveillance , Recurrence , Rehabilitation/statistics & numerical data , Reoperation/statistics & numerical data , Retrospective Studies , Severity of Illness Index , Surveys and Questionnaires
18.
Heart ; 99(17): 1275-81, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23825097

ABSTRACT

OBJECTIVE: Surgical correction of congenital aortic coarctation can lead to a number of important problems including late pseudoaneurysm formation. Redo surgery has a significant risk. Endovascular stent graft repair is increasingly used but there are limited data regarding this indication. We describe the experience of two UK congenital referral centres. DESIGN: Retrospective analysis of patients treated with endovascular aortic stent grafting for late pseudoaneurysms. SETTING: Two UK congenital heart centres, Bristol Heart Institute and Leeds General Infirmary. PATIENTS: 17 patients were treated 2006-2012. This represents all patients treated with this technique. MAIN OUTCOME MEASURES: Procedural and postprocedure success and complications. RESULTS: The average time from index repair to endovascular repair of pseudoaneurysm was 24.6 years. The majority (70.6%) had patch aortoplasty as the original surgical procedure and 41.2% were not under follow-up or discharged. Stent grafting procedural success rate was 100%. Median hospital stay postprocedure was 3 days. There was no procedural mortality or immediate complication. There were four minor early and three minor late complications. Imaging follow-up was available for an average of 31.6 months (range 6-65 months). All patients have demonstrated positive remodelling of the pseudoaneurysm with no incidence of continued expansion or stent graft failure up to 5 years following implant. CONCLUSIONS: Endovascular stent graft treatment of pseudoaneurysms show promising results in a population who have a high risk of surgical re-intervention. Complication rates appear to be low and recovery is quick. Longer-term data remain essential to scrutinise stent graft performance in this situation.


Subject(s)
Aneurysm, False/etiology , Aortic Coarctation/complications , Blood Vessel Prosthesis Implantation/methods , Endovascular Procedures/methods , Stents , Adult , Aged , Aneurysm, False/diagnostic imaging , Aneurysm, False/surgery , Aortic Coarctation/diagnostic imaging , Aortic Coarctation/surgery , Blood Vessel Prosthesis Implantation/adverse effects , Blood Vessel Prosthesis Implantation/mortality , Endovascular Procedures/adverse effects , Endovascular Procedures/mortality , Female , Humans , Male , Postoperative Complications/mortality , Retrospective Studies , Tomography, X-Ray Computed , Transplants , Treatment Outcome , United Kingdom
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