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Dive into the research topics where H.W.Thijs Plokker is active.

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Featured researches published by H.W.Thijs Plokker.


Circulation | 1996

Smoking and Cardiac Events After Venous Coronary Bypass Surgery A 15-Year Follow-up Study

Adriaan A. Voors; Ben L. van Brussel; H.W.Thijs Plokker; Sjef M.P.G. Ernst; Nicolette M. Ernst; Egbert M. Koomen; Jan G.P. Tijssen; F. E. E. Vermeulen

BACKGROUND The long-term clinical effects of smoking and smoking cessation after venous coronary bypass surgery have not been well established. METHODS AND RESULTS Four hundred fifteen patients who underwent venous coronary bypass surgery between April 1976 and April 1977 were followed up prospectively for 15 years. Multivariate Cox survival analysis revealed that patients who smoked at the time of surgery had no elevated risks for clinical events compared with nonsmokers. However, smoking behavior at 1 and 5 years after surgery appeared to be an important predictor of clinical events during the subsequent follow-up period. Compared with patients who stopped smoking since surgery, smokers at 1 year after surgery had more than twice the risk for myocardial infarction and reoperation. Patients who were still smoking at 5 years after surgery had even more elevated risks for myocardial infarction and reoperation and a significantly increased risk for angina pectoris compared with patients who stopped smoking since surgery and patients who never smoked. Patients who started to smoke again within 5 years after surgery had increased risks for reoperation and angina pectoris. No differences in outcome were found between patients who stopped smoking since surgery and nonsmokers. CONCLUSIONS Our results show that smoking cessation after coronary bypass surgery may have important beneficial effects on clinical events during long-term follow-up.


Journal of the American College of Cardiology | 1993

Immediate sealing of arterial puncture sites after cardiac catheterization and coronary angioplasty using a biodegradable collagen plug: results of an international registry.

Sjef M.P.G. Ernst; R.Melvyn Tjonjoegin; Rainer Schräder; Kaltenbach M; Ulrich Sigwart; Timothy A. Sanborn; H.W.Thijs Plokker

OBJECTIVES The aim of this study was to evaluate the safety and efficacy of a biodegradable collagen plug that has been developed to reduce the arterial compression time required to achieve hemostasis at the arterial puncture site after diagnostic and interventional coronary procedures. BACKGROUND After diagnostic and interventional coronary catheterization procedures, local arterial compression is required to achieve hemostasis and complications may ensue, especially in patients on full anticoagulation. METHODS Between March 1991 and July 1991, 252 patients admitted for routine coronary angiography or angioplasty to four large hospitals received such a hemostatic device immediately after the procedure. Hemostasis was achieved with collagen in 87% of patients after a mean compression time of 4.8 min. Time to hemostasis was independent of the heparin load. A total of 54 hematomas (21%) was reported; all but 2 resolved without additional treatment. Two patients had a severe hematoma, requiring blood transfusion, and two patients required surgery to repair a pseudoaneurysm. During a follow-up period of 4 weeks no severe late complications were reported. CONCLUSIONS We conclude that the collagen plug appears to be a safe device to achieve hemostasis at the arterial puncture site, independent of anticoagulation.


American Journal of Cardiology | 1991

The Dutch experience in percutaneous transluminal angioplasty of narrowed saphenous veins used for aortocoronary arterial bypass

H.W.Thijs Plokker; B.Hannie Meester; Patrick W. Serruys

Of 19,994 percutaneous transluminal coronary angioplasty procedures performed in The Netherlands between April 1980 and January 1989, the long-term follow-up of 454 patients who underwent angioplasty of greater than or equal to 1 saphenous vein bypass graft was reviewed. In 46% of patients single graft angioplasty was attempted, and in 54% of patients sequential graft angioplasty was attempted. The clinical primary success rate was 90%. In-hospital mortality was 0.7%, 2.8% of patients sustained a procedural myocardial infarction, and 1.3% of patients underwent emergency bypass surgery. After a follow-up period of 5 years, 74% of patients were alive, and 26% were alive and event-free (no myocardial infarction, no repeat bypass surgery or repeat angioplasty). In patients in whom the initial angioplasty attempt was unsuccessful, only 3% were event-free at 5 years, versus 27% of successfully dilated patients. The time interval between the angioplasty attempt and previous surgery was a significant predictor for 5-year event-free survival. The event-free survival rates for patients who had bypass surgery 1 year before, between 1 and 5 years, and 5 years before angioplasty, were 45, 25 and 19%, respectively. Less than one-third of patients with previous bypass surgery who had angioplasty of the graft remained event-free after 5 years. In patients needing angioplasty within 1 year after bypass surgery, better long-term results were achieved.


Circulation | 2000

Effect of Coumarins Started Before Coronary Angioplasty on Acute Complications and Long-Term Follow-Up A Randomized Trial

Jurriën M. ten Berg; Johannes C. Kelder; Maarten J. Suttorp; E. Gijs Mast; Egbert T. Bal; Sjef M.P.G. Ernst; Freek W.A. Verheugt; H.W.Thijs Plokker

BACKGROUND Coronary angioplasty frequently creates a thrombogenic surface, with subsequent mural thrombosis that may lead to acute complications and possibly stimulates the development of restenosis. Whether coumarins can prevent these complications is unclear. The objective of this open, randomized trial was to assess the clinical effect of coumarins started before coronary angioplasty and continued for 6 months. METHODS AND RESULTS Before coronary angioplasty, 530 patients were randomly assigned to aspirin plus coumarins and 528 patients to aspirin alone. At the start of the angioplasty, the mean international normalized ratio was 2.7+/-1.1; during follow-up, it was 3.0+/-1.1. At 30 days, the composite end point of death, myocardial infarction, target-lesion revascularization, and stroke was observed in 18 patients (3.4%) treated with aspirin plus coumarin compared with 34 patients (6.4%) treated with aspirin alone (relative risk, 0.53; 95% CI, 0.30 to 0.92). At 1 year, these figures were 14.3% and 20.3%, respectively (relative risk, 0.71; 95% CI, 0.54 to 0.93). The incidence of major bleeding and false aneurysm during hospitalization was 3.2% and 1.0%, respectively (relative risk, 3.39; 95% CI, 1.26 to 9.11). The benefit of coumarins was observed in both stented and nonstented patients. CONCLUSIONS Coumarins in addition to aspirin started before PTCA and continued for 6 months was more effective than aspirin alone in the prevention of acute and late complications after coronary angioplasty. This benefit was accompanied by a small but significant increase in bleeding complications.


Journal of The American Society of Echocardiography | 2003

Additional value of three-dimensional transesophageal echocardiography for patients with mitral valve stenosis undergoing balloon valvuloplasty

Jorina Langerveld; H.W.Thijs Plokker; Sjef M.P.G. Ernst; Herman F.J. Mannaerts; Johannes C. Kelder; Otto Kamp; Wybren Jaarsma

The objective of this study was to validate the additional value of 3-dimensional (3D) transesophageal echocardiography (TEE) for patients with mitral valve stenosis undergoing percutaneous mitral balloon valvotomy (PTMV). Therefore, in a series of 21 patients with severe mitral valve stenosis selected for PTMV, 3D TEE was performed before and after PTMV. The mitral valve area was assessed by planimetry pre- and post-PTMV; the mitral valve volume was assessed and attention was paid to the amount of fusion of the commissures. These results were compared with findings by 2-dimensional transthoracic echocardiography using pressure half-time method for assessment of mitral valve area, and were analyzed for the prediction of successful outcome. Pre-PTMV the mitral valve area assessed by 3D TEE was 1.0 +/- 0.3 cm(2) vs 1.2 +/- 0.4 cm(2) assessed by 2-dimensional transthoracic echocardiography (P =.03) and post-PTMV it was 1.8 +/- 0.5 cm(2) vs 1.9 +/- 0.6 cm(2) (not significant), respectively. The mitral valve volume could be assessed by 3D TEE (mean 2.4 +/- 2.5 cm(3)) and was inversely correlated to a successful PTMV procedure (P <.001). The 3D TEE method enabled a better description of the mitral valvular anatomy, especially post-PTMV. We conclude that 3D TEE will have additional value over 2-dimensional echocardiography in this group of patients, for selection of patients pre-PTMV, and for analyzing pathology of the mitral valve afterward.


American Journal of Cardiology | 1996

Percutaneous Transluminal Angioplasty of the Left Subclavian Artery to Prevent or Treat the Coronary-Subclavian Steal Syndrome

Koen M. Marques; Sjef M.P.G. Ernst; E. Gijs Mast; Egbert T. Bal; Maarten-Jan Suttorp; H.W.Thijs Plokker

A hemodynamic significant left subclavian artery stenosis or occlusion proximal to the origin of the left internal mammary artery (LIMA) can result in an impaired or reversed flow through the LIMA and the coronary artery to which it has been anastomosed. In this study, we report on our immediate and long-term follow-up results in 31 consecutive patients who underwent percutaneous transluminal coronary angioplasty of the left subclavian artery shortly before or after coronary artery bypass grafting with use of the LIMA.


Journal of the American College of Cardiology | 2001

Influence of planned six-month follow-up angiography on late outcome after percutaneous coronary intervention: A randomized study☆

Jurriën M. ten Berg; Johannes C. Kelder; Maarten J. Suttorp; Freek W.A. Verheugt; H.W.Thijs Plokker

OBJECTIVES The goal of this research was to study the effect of planned angiography on late clinical outcome after percutaneous coronary intervention. BACKGROUND It is still largely unknown whether planned follow-up angiography after coronary angioplasty influences late outcome. METHODS Randomization assigned 527 patients to clinical follow-up alone and 531 to clinical and six-month angiographic follow-up. The effect of planned angiography on clinical outcome at one and three years after coronary angioplasty was studied. RESULTS The two groups were well matched. At one year, more events occurred in the angiographic group than in the clinical group: 122 (23.2%) versus 88 (16.7%) (p = 0.01). While the incidence of death or myocardial infarction (MI) was similar at one year, the revascularization rate was higher in the angiographic group: 113 (21.3%) versus 67 (12.7%) (relative risk = 1.7, 95% confidence interval: 1.3 to 2.3, p = 0.0003). At three years, still more events had occurred in the angiographic group (146 [34.5%] vs. 114 [26.3%], p = 0.03). More reinterventions did not improve late survival. However, there was a nonsignificant reduction in MI (7 [1.3%] vs. 13 [2.5%], p = NS) and a significant improvement in functional class at the end of follow-up (freedom from angina 81% vs. 74%, p = 0.03). The effect of follow-up angiography on the reintervention rate was similar for stented and nonstented patients. CONCLUSIONS Planned follow-up angiography to evaluate the late results of coronary intervention led to a 1.7 times higher reintervention rate. This effect was similar for stented and nonstented patients. More reinterventions did not improve survival but tended to reduce the incidence of MI and led to a significantly better functional class at follow-up.


Catheterization and Cardiovascular Interventions | 2006

Comparison of outcome and complications using different types of devices for percutaneous closure of a secundum atrial septal defect in adults: A single-center experience

Martijn C. Post; Maarten J. Suttorp; Wybren Jaarsma; H.W.Thijs Plokker

The objective of this study was to find differences in outcome and complications using three different types of devices for percutaneous atrial septal defect (ASD) closure in adults. Percutaneous closure of a secundum‐type ASD is increasingly performed in adult patients. All adult patients who underwent a percutaneous closure of a secundum‐type ASD in our center between November 1996 and November 2004 were included. Failure was defined as dislocation or embolization of the device, which required surgical intervention. Periprocedural and mid‐term complications were registered. Sixty‐five patients, mean age 45.7 ± 18.1 years (18 men, 47 women), underwent a percutaneous closure of an ASD with an ASDOS in 3, an Amplatzer in 36, and a Cardioseal/Starflex closure device in 26 patients. During an overall median follow‐up of 1.2 years (range, 0.1–6.7 years), the failure occurred in four patients, all Cardioseal/Starflex (P = 0.04). Within the Cardioseal/Starflex subgroup, the ASD and device diameters were significantly higher in those patients in whom the primary endpoint occurred compared to the others, 18.8 ± 3.8 vs. 13.0 ± 3.8 mm for ASD diameter (P = 0.01) and 40 (range, 40–43) vs. 33 mm (range, 20–40) for device diameter (P = 0.008). Overall complications were transient arrhythmias in 15.4%, pericardial effusion in 1.5%, and transient ischemic attack in 1.5%. Complete closure 6 months after the procedure occurred in 79.6%, without difference between the devices. Percutaneous ASD closure seems to be a relatively safe and effective procedure. However, using the larger Cardioseal/Starflex devices for closure seems to be related to a higher rate of device dislocation and embolization.


Circulation | 2001

Oral anticoagulant therapy during and after coronary angioplasty - The intensity and duration of anticoagulation are essential to reduce thrombotic complications

Jurriën M. ten Berg; Barbara A. Hutten; Johannes C. Kelder; Freek W.A. Verheugt; H.W.Thijs Plokker

BackgroundIn the randomized Balloon Angioplasty and Anticoagulation Study (BAAS), the addition of oral anticoagulants to aspirin significantly reduced early and late events after coronary angioplasty. However, bleeding episodes were increased. The present report studied the intensity and the duration of anticoagulation as predictors of thrombotic and bleeding events. Methods and ResultsA total of 530 patients, 34% of whom received a stent, were treated with aspirin plus coumarins. Half of the patients were randomized to angiographic follow-up. The target international normalized ratio (INR) was 2.1 to 4.8 during angioplasty and 6-month follow-up. Thrombotic events were death, myocardial infarction, target lesion revascularization, and thrombotic stroke. Bleeding complications were hemorrhagic stroke, major extracranial bleeding, and false aneurysm. “Optimal” anticoagulation was defined as an INR in the target range for at least 70% of the follow-up time. There were 17 early thrombotic events (3.2%), 7 early bleeding episodes (1.3%), and 10 false aneurysms (1.9%). The incidence rate for both early thrombotic and bleeding events was lowest in patients in the target range. A total of 61 late thrombotic events occurred (11.6%). Optimal anticoagulation was an independent predictor of late thrombotic events (relative risk, 0.33; 95% CI, 0.19 to 0.57) and was associated with a 0.21 mm (95% CI, 0.17 to 0.42) larger vessel lumen at 6 months. Late bleeding episodes (1.4%) were lowest in patients in the target range. ConclusionsCoumarins started before coronary angioplasty with a target INR of 2.1 to 4.8 led to the lowest procedural event rate, without an increase in bleeding episodes. During follow-up, optimal anticoagulation was associated with a decrease in the incidence of late events by 67% and a significant improvement in 6-month angiographic outcome.


American Journal of Cardiology | 1996

Long-term results after successful percutaneous transluminal coronary angioplasty in patients over 75 years of age

Jurrien M. ten Berg; Adriaan A. Voors; Maarten J. Suttorp; Sjef M.P.G. Ernst; E. Gijs Mast; Egbert T. Bal; H.W.Thijs Plokker

A prospective study comparing the long-term results of balloon angioplasty in patients over 75 years of age with those in a younger patient group is not available. A total of 192 consecutive patients aged > or = 75 years (group I) who underwent a balloon angioplasty were matched with 192 control patients aged 40 to 65 years (group II). The groups were matched for gender, angina pectoris class, left ventricular function, 1-, 2-, and 3-vessel coronary artery disease, and previous myocardial infarction. The mean follow-up was 40.4 months (range 0 to 110). Actuarial analysis (freedom from events) after 5 years yielded the following results for group I versus group II: free from death remained 77.1% versus 97.9% (p = 0.0001), from cardiac death 92.4% versus 97.9% (p = 0.049), and from angina pectoris 54.6% versus 75.1% (p = 0.03). The differences were not significant for those remaining free from myocardial infarction, repeat balloon angioplasty, or coronary artery bypass grafting. When elderly patients with complete revascularization (n = 127) were compared with a matched control group of 127 patients aged 40 to 65 years who underwent complete revascularization, there was only a significant difference in noncardiac death rates. We conclude that patients > 75 years of age have a significant higher cardiac and noncardiac death rate and a higher incidence of angina pectoris after successful balloon angioplasty. However, the incidence of reintervention and myocardial infarction is lower in the elderly. If complete revascularization is achieved in the elderly, then freedom from cardiac death and recurrence of angina pectoris would be comparable to that in younger patients.

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Johannes C. Kelder

Erasmus University Rotterdam

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Adriaan A. Voors

University Medical Center Groningen

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Benno J. Rensing

Erasmus University Rotterdam

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Dirk J. van Veldhuisen

University Medical Center Groningen

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Wiek H. van Gilst

University Medical Center Groningen

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Martijn C. Post

Katholieke Universiteit Leuven

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