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Featured researches published by P. N. Ruygrok.


Circulation | 1996

Heparin-coated Palmaz-Schatz stents in human coronary arteries. Early outcome of the Benestent-II Pilot Study.

P. W. Serruys; H. Emanuelsson; W.J. van der Giessen; A. C. Lunn; F. Kiemeney; Carlos Macaya; Wolfgang Rutsch; Guy R. Heyndrickx; H. Suryapranata; Victor Legrand; Jean-Jacques Goy; Phillipe Materne; H. Bonnier; M.C. Morice; J. Fajadet; J. Belardi; Antonio Colombo; E. Garcia; P. N. Ruygrok; P. de Jaegere; M. A. Morel

BACKGROUND The purpose of the Benestent-II Pilot Study was to evaluate the safety of delaying and eliminating anticoagulant therapy in patients receiving a heparin-coated stent in conjunction with antiplatelet drugs. METHODS AND RESULTS The study consisted of three initial phases (I, II, III) during which resumption of heparin therapy after sheath removal was progressively deferred by 6, 12, and 36 hours. In phase IV, coumadin and heparin were replaced by 250 mg ticlopidine and 100 mg aspirin. Of the 207 patients with stable angina pectoris and a de novo lesion in whom heparin-coated stent implantation was attempted, implantation was successful in 202 patients (98%). Stent thrombosis did not occur during all four phases, and the overall clinical success rate at discharge was 99%. Bleeding complications requiring blood transfusion or surgery fell from 7.9% in phase I to 5.9%, 4%, and 0% in the three following phases. Hospital stay was 7.4, 6.1, 7.2, and 3.1 days for the consecutive phases. The restenosis rate for the combined four phases was 13% (15% in phase I, 20% in phase II, 11% in phase III, and 6% in phase IV). The overall rate of reintervention for the four phases was 8.9%. At 6 months, 84%, 75%, 94%, and 92% of the patients of phases I to IV, respectively, were event free. For the four phases, the event-free rate was 86%, which compares favorably with the rate observed in the Benestent-I study (80%; relative risk, 0.68 [0.45 to 1.04]). CONCLUSIONS The implantation of stents coated with polyamine and end-point-attached heparin in stable patients with one significant de novo coronary lesion is well tolerated, is associated with no (sub)acute stent thrombosis, and results in a favorable event-free survival after 6 months.


Journal of the American College of Cardiology | 1996

Initial results of combined anterior mitral leaflet extension and myectomy in patients with obstructive hypertrophic cardiomyopathy

Marcel Kofflard; Lex A. van Herwerden; David Waldstein; P. N. Ruygrok; Eric Boersma; Meindert A. Taams; Folkert J. ten Cate

OBJECTIVES The purpose of this study was to describe the clinical and functional results of combined anterior mitral leaflet extension and myectomy in patients with hypertrophic obstructive cardiomyopathy. BACKGROUND Septal myectomy is the most commonly performed surgical procedure in patients with hypertrophic cardiomyopathy and left ventricular outflow tract obstruction. Because of the role of the mitral valve in creating the outflow tract gradient, mitral valve replacement or plication is performed in selected cases in combination with myectomy, often with better hemodynamic results than those of myectomy alone. Mitral valve leaflet extension, in which a glutaraldehyde-preserved autologous pericardial patch is used to enlarge the mitral valve along its horizontal axis, is a novel surgical approach in patients with hypertrophic obstructive cardiomyopathy. METHODS Eight patients with hypertrophic obstructive cardiomyopathy were treated with mitral leaflet extension and myectomy. Preoperative and postoperative data (New York Heart Association functional class, number of drugs prescribed, width of the interventricular septum, severity of mitral valve regurgitation severity of systolic anterior motion of the mitral valve and outflow tract gradient) were compared with those of 12 patients undergoing myectomy alone. RESULTS Preoperative evaluation demonstrated that mitral regurgitation and systolic anterior motion of the mitral valve were more severe in the group undergoing mitral valve extension (p < 0.001 and p < 0.05, respectively). There were no deaths associated with either surgical procedure. Two patients, both treated by myectomy alone, died during the follow-up period. Postoperatively, patients treated with mitral valve extension had less mitral regurgitation (p < 0.005), less residual systolic anterior motion (p < 0.001), greater improvement in functional class (p = 0.05) and greater reduction in the number of drugs (p < 0.005) and in septal thickness (p < 0.05). CONCLUSIONS Mitral leaflet extension in combination with myectomy is a promising new surgical approach that may provide superior results to those of myectomy alone. Further studies are needed to determine the clinical value of this procedure.


Circulation | 1996

Intracoronary Stenting From Concept to Custom

P. N. Ruygrok; Patrick W. Serruys

When Charles Stent, a 19th century English dentist, developed a mold with which to form an impression of the teeth and oral cavity, he would never have imagined that his name would become synonymous with the management of obstructive vascular disease, in particular coronary artery disease (Fig 1⇓).1 The term “stent” became associated with a device that held a skin graft in position, a support for tubular structures that were being anastomosed, and, more recently, an endovascular scaffolding to relieve and prevent vascular obstructions. Figure 1. Charles Stent (1845-1901), an English dentist who lent his name to a tooth mold (bottom) and more recently to endoluminal scaffolding devices. The management of coronary atherosclerosis has shifted from “masterly inactivity” to medical therapy, coronary bypass surgery, and, more recently, percutaneous techniques introduced by Gruentzig et al in 1977.2 Intracoronary stenting with continuing refinements appears poised to become the mainstay of the mechanical treatment of obstructive coronary disease. In his 1912 Nobel lecture, laureate Alexis Carrel described experiments with glass and metal tubes covered with paraffin that were introduced into canine thoracic aortae. Coagulation did not occur provided the aortic wall was not ulcerated, with one animal surviving for 90 days with a glass tube. He concluded that the presence of foreign bodies within vessels did not necessarily produce thrombus. The concept of using an implantable prosthetic device to maintain the luminal integrity of diseased vessels was reintroduced by Charles Dotter in 1964, when he suggested that the temporary use of a silicone elastomer endovascular splint could maintain an adequate lumen after the creation of a pathway in a previously occluded vessel.3 In 1969, he reported the results of the nonsurgical endarterial placement of spiral springs, mounted coaxially on a guidewire and positioned with a pusher catheter in the femoral …


Circulation | 1996

Six-Month Clinical and Angiographic Outcome of the New, Less Shortening Wallstent in Native Coronary Arteries

Yukio Ozaki; David Keane; P. N. Ruygrok; Willem J. van der Giessen; Pim J. de Feyter; Patrick W. Serruys

BACKGROUND The new, less shortening, self-expanding Wallstent is characterized by longitudinal flexibility, a protective membrane, a low profile, and a customized range of diameters (3.5 to 6.0 mm). The recent modification of the braiding angle of the Wallstent has resulted in a new device with less shortening on expansion and a concomitant reduction in radial force. We hypothesized that the enforced mechanical remodeling produced by the selection of an oversized Wallstent might result in improved accommodation of subsequent reactive intimal hyperplasia and prevention of chronic recoil of the vessel. METHODS AND RESULTS To prove this hypothesis, we recently implanted 44 new, less shortening Wallstents in 35 native coronary arteries in 35 patients with acute or threatened closure after balloon angioplasty, according to a strategy of oversizing of Wallstent diameter and complete coverage of the lesion length. The initial and 6-month follow-up angiograms were analyzed with a computer-based quantitative coronary angiography (QCA) system. Acute gain (minimal luminal diameter [MLD] post minus MLD pre) and late loss (MLD post minus MLD at follow-up) were examined. Stent deployment was successful in 44 of 44 attempts (100%). Nominal stent diameter used was 1.40 mm larger than the maximal vessel diameter. One patient (3%) with a dilated but unstented lesion proximal to the stented segment sustained a subacute occlusion on day 1 associated with myocardial infarction. Event-free survival at 30 days after stent implantation was 97% (34 of 35 patients). Of the 34 patients eligible for 6-month angiographic follow-up, 3 who were asymptomatic declined repeat angiography. MLD (and percent diameter stenosis [% DS]) changed from 0.83 +/- 0.50 mm (72%) pre through 3.06 +/- 0.48 mm (15%) post to 2.27 +/- 0.74 mm (28%) at follow-up. Acute gain was 2.23 +/- 0.63 mm, and late loss was 0.78 +/- 0.61 mm. Angiographic restenosis ( > 50% DS) was observed in 5 of 31 patients (16%) at 6 months, all of whom underwent repeat angioplasty. Thus, the overall event-free survival at 6-month follow-up was 83% (29 of 35 patients). CONCLUSIONS The oversized Wallstent implantation with complete coverage of the lesion length conveyed a favorable 6-month clinical and angiographic outcome. The large acute gain obtained by the Wallstent afforded greater accommodation of the subsequent late loss. The enforced mechanical remodeling by oversized new Wallstents may result in prevention of acute and chronic recoil of the vessel wall and subsequently a lower restenosis rate at follow-up.


Journal of the American College of Cardiology | 1996

Clinical outcome 10 years after attempted percutaneous transluminal coronary angioplasty in 856 patients

P. N. Ruygrok; Peter de Jaegere; Ron T. van Domburg; Marcel van den Brand; Patrick W. Serruys; Pim J. de Feyter

OBJECTIVES This study reports the 10-year outcome of 856 consecutive patients who underwent attempted coronary angioplasty at the Thoraxcenter during the years 1980 to 1985. BACKGROUND Coronary balloon angioplasty was first performed in 1977, and this procedure was introduced into clinical practice at the Thoraxcenter in 1980. Although advances have been made, extending our knowledge of the long-term outcome in terms of survival and major cardiac events remains of interest and a valuable guide in the treatment of patients with coronary artery disease. METHODS Details of survival, cardiac events, symptoms and medication were retrospectively obtained from the Dutch civil registry, medical records or by letter or telephone or from the patients physician and entered into a dedicated data base. Patient survival curves were constructed, and factors influencing survival and cardiac events were identified. RESULTS The procedural clinical success rate was 82%. Follow-up information was obtained in 837 patients (97.8%). Six hundred forty-one patients (77%) were alive, of whom 334 (53%) were symptom free, and 254 (40%) were taking no antianginal medication. The overall 5- and 10-year survival rates were 90% (95% confidence interval [CI] 87.6% to 92.4%) and 78% (95% CI 75.0% to 81.0%), respectively, and the respective freedom from significant cardiac events (death, myocardial infarction, coronary artery bypass surgery and repeat angioplasty) was 57% (95% CI 53.4% to 60.6%) and 36% (95% CI 32.4% to 39.6%). Factors that were found to adversely influence 10-year survival were age > or = 60 years (> or = 60 years [67%], 50 to 59 years [82%], < 50 years [88%]), multivessel disease (multivessel disease [69%], single-vessel disease [82%]), impaired left ventricular function (ejection fraction < 50% [57%], > or = 50% [80%]) and a history of previous myocardial infarction (previous myocardial infarction [72%], no previous infarction [83%]). These factors were also found to be independent predictors of death during the follow-up period by a multivariate stepwise logistic regression analysis. Other factors tested, with no influence on survival, were gender, procedural success and stability of angina at the time of intervention. CONCLUSIONS The long-term prognosis of patients after coronary angioplasty is good, particularly in those <60 years old with single-vessel disease and normal left ventricular function. The majority of patients are likely to experience a further cardiac event in the 10 years after their first angioplasty procedure.


Heart | 1995

Immediate and long-term clinical outcome of coronary angioplasty in patients aged 35 years or less.

Marcel Kofflard; P.P. De Jaegere; R.T. van Domburg; P. N. Ruygrok; M. van den Brand; P. W. Serruys; P. J. De Feyter

OBJECTIVE--To study the immediate and long-term clinical success of percutaneous transluminal coronary angioplasty in patients aged 35 years or less. DESIGN--Patients undergoing percutaneous transluminal angioplasty were prospectively entered into a dedicated database. Clinical and angiographic data on all patients aged 35 years or less were reviewed. Follow up data were collected by interview during outpatient visits, by questionnaire, or from referring physicians. SETTING--A tertiary referral cardiac centre. PATIENTS--57 patients aged 35 years or less (median 33, range 22-35) underwent coronary angioplasty because of unstable angina (32 patients), stable angina (23 patients), acute myocardial infarction (1 patient), and documented ischaemia in a cardiac transplant patient. RESULTS--The primary clinical success rate (reduction in diameter stenosis to < 50% without in-hospital events) was 88%. A major procedure related complication occurred in 5 patients (9%): one patient died, two patients sustained an acute myocardial infarction, two patients underwent emergency bypass surgery, and in three patients repeat angioplasty was performed before hospital discharge. In 2 patients (4%) coronary angioplasty did not significantly reduce the diameter stenosis but there were no associated complications. A total of 60 lesions were attempted (balloon angioplasty in 57, directional atherectomy in 2). The initial angiographic success rate was 92%. The median (SD) follow up was 4.7 (3.0) years. During follow up 7 patients (12%) died, 10 sustained a myocardial infarction (18%), and 28 patients (49%) underwent repeat revascularisation (coronary artery bypass grafting in 7 (12%) and repeat angioplasty in 21 (37%)). The estimated 5 year survival and event-free survival (Kaplan-Meier method) was 87 (9)% and 50 (13)%, respectively. Multivariate logistic regression analysis showed that hypertension and the extent of vessel disease were the only independent predictive factors for event free survival. CONCLUSIONS--In young patients coronary angioplasty had a high immediate success rate but many needed repeat revascularisation procedures during the follow up period and survival was not improved. Coronary angioplasty in young patients should be regarded as a palliative procedure.


Catheterization and Cardiovascular Diagnosis | 1996

Women fare no worse than men 10 years after attempted coronary angioplasty.

P. N. Ruygrok; Peter de Jaegere; Ron T. van Domburg; Marcel van den Brand; Patrick W. Serruys; Pim J. de Feyter

A retrospective review of cardiac events occurring in all patients who underwent attempted coronary angioplasty in the first 5 years of our experience (1980-1985) was undertaken. Follow-up data were obtained from the civil registry, hospital records, patient, family, and referring physician. Patient survival curves were constructed and the outcome of women and men was compared. Eight hundred fifty-six patients, 172 women and 684 men with a mean age of 60.0 and 55.3 years, respectively, underwent attempted coronary angioplasty with an overall procedural success rate of 82%, 77.7% in women and 83.1% in men. Follow-up data were obtained in 837 patients (97.8%) with a mean period of 9.6 years (range 0-13.3 years). The estimated 10 year survival in women was identical to men [79%, 95% confidence interval (CI) 72.6-85.4% vs. 78%, 95% CI 74.6-81.4%] as was the 10 year event-free survival (men 36%, 95% CI 32.0-40.0% vs. women 37%, 95% CI 29.2-44.8%), with a similar proportion of major cardiac events-death, myocardial infarction, coronary artery bypass surgery, and repeat angioplasty. When women were matched to men for age and previous myocardial infarction, factors found to be associated with an adverse outcome, there was no significant difference. Additionally, outcome was compared after patients were matched for maximum nominal balloon size as an estimate of vessel size, with no significant difference between women and men. At follow-up, women complained of significantly more anginal symptoms than men (59.2% vs. 44.0%, P < 0.05) and took significantly more antianginal medication.


European Heart Journal | 1995

Coronary intervention: Risk stratification and management of abrupt coronary occlusion

P. J. De Feyter; P. N. Ruygrok


European Heart Journal | 1995

Immediate outcome following coronary angioplastyA contemporary single centre audit

P. N. Ruygrok; P. de Jaegere; J. Verploegh; R.T. van Domburg; P. J. De Feyter


European Heart Journal | 1995

Immediate outcome following coronary angioplasty

P. N. Ruygrok; P. de Jaegere; J. Verploegh; R.T. van Domburg; P. J. De Feyter

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P. J. De Feyter

Erasmus University Rotterdam

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P. de Jaegere

Erasmus University Rotterdam

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Pim J. de Feyter

Erasmus University Rotterdam

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Peter de Jaegere

Erasmus University Rotterdam

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R.T. van Domburg

Erasmus University Rotterdam

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P. W. Serruys

Erasmus University Rotterdam

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Marcel Kofflard

Albert Schweitzer Hospital

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Marcel van den Brand

Erasmus University Rotterdam

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Ron T. van Domburg

Erasmus University Rotterdam

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