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Pieter C Smits

Publications and source records attributed to Pieter C Smits.

At least 37 records · Page 2Linked to original sources
PubMed2004

Clinical and angiographic outcomes after overdilatation of undersized sirolimus-eluting stents with largely oversized balloons: an observational study.

The purpose of this study was to assess the safety and effectiveness of sirolimus-eluting stent (SES) postdilatation with largely oversized balloons. We evaluated the clinical outcome of 68 consecutive patients enrolled in the Rapamycin-Eluting Stent Evaluated at Rotterdam Cardiology Hospital (RESEARCH) registry who underwent percutaneous coronary intervention with SES implantation and further postdilatation with balloons > 1 mm larger than the stent nominal size. Angiographic follow-up was either scheduled for selected subgroups or clinically driven. Overall, 75 lesions were treated. The procedure was successful in 98.5% of the cases. One patient (1.5%) underwent emergency coronary bypass surgery for acute vessel occlusion. During 10.1 +/- 1.7 months of follow-up, three patients (4.5%) died, one (1.5%) had acute myocardial infarction, and four (6%) had target vessel revascularization. At angiographic follow-up, loss index was 0.13 +/- 0.34 and restenosis rate was 7.7%. Although not routinely recommended in every patient, SES postdilatation with largely oversized balloons appears a safe and effective strategy for selected patients.

Aged↗
PubMed2004

Elective sirolimus-eluting stent implantation for left main coronary artery disease: six-month angiographic follow-up and 1-year clinical outcome.

The effectiveness of sirolimus-eluting stent (SES) implantation in patients treated electively for left main (LM) stenoses has not been yet ascertained. The present study reports on the clinical and angiographic outcome of 16 consecutive patients treated electively for de novo stenoses in the LM. The impact of SES implantation on major adverse cardiac events was evaluated. Mean age was 65 +/- 11 years. Unprotected LM was present in nine (56%), and eight patients (50%) received stents extending into both the left anterior descending and circumflex arteries for stenoses of the distal left main bifurcation. In-house mortality and reintervention rate was zero. One patient developed a non-Q-wave myocardial infarction related to the index procedure. At 1-year clinical follow-up, there were no deaths or further myocardial infarctions; one (6%) patient required target lesion revascularization. A total of 12 patients (75%) underwent 6-month angiographic follow-up with a late lumen loss of 0.04 +/- 0.65 mm and one focal restenosis (8% of patients). Elective SES implantation for LM disease was associated with zero mortality and a very low incidence of additional major adverse events at 1 year.

Aged↗
PubMed2004

Clinical outcomes for sirolimus-eluting stent implantation and vascular brachytherapy for the treatment of in-stent restenosis.

The purpose of this study was to compare the mid-term clinical outcome of sirolimus-eluting stent (SES) implantation and vascular brachytherapy (VBT) for in-stent restenosis (ISR). We assessed the 9-month occurrence of major adverse cardiac events (MACE) in 44 consecutive patients with ISR treated with SES implantation and 43 consecutive patients treated with VBT in the period immediately prior. Baseline clinical and angiographic characteristics of the two groups were similar. During follow-up, three patients (7%) died in the VBT group and none in the SES group. The incidence of myocardial infarction was 2.3% in both groups. Target lesion revascularization was performed in 11.6% of the VBT patients and 16.3% of the SES patients (P = NS). The 9-month MACE-free survival was similar in both groups (79.1% VBT vs. 81.5% SES; P = 0.8 by log rank). The result of this nonrandomized study suggests that sirolimus-eluting stent implantation is at least as effective as vascular brachytherapy in the treatment of in-stent restenosis.

Brachytherapy↗
PubMed2004

Elective sirolimus-eluting stent implantation for multivessel disease involving significant LAD stenosis: one-year clinical outcomes of 99 consecutive patients--the Rotterdam experience.

The aim of this study was to evaluate the effectiveness of sirolimus-eluting stent (SES) implantation for patients with multivessel disease, which included left anterior descending artery (LAD) treatment. Since April 2002, SES has been utilized as the device of choice for all interventions in our institution as part of the Rapamycin-Eluting Stent Evaluated at Rotterdam Hospital (RESEARCH) registry. In the first 6 months of enrollment, 99 consecutive patients (17.6% of the total population) were treated for multivessel disease involving the LAD. The impact of SES implantation on major adverse cardiac events (MACE) was evaluated. All the patients received SES in the LAD. Additional stent implantation in the right coronary artery, the left circumflex, or in all three major vessels was attempted successfully in 32 (32%), 51 (52%), and 16 (16%) of the treated patients respectively. During a mean follow-up of 360 +/- 59 days (range, 297-472 days), we had one death, one non-Q-wave myocardial infarction, and eight patients required subsequent intervention. The event-free survival of MACE at 1 year was 85.6%. SES implantation for multivessel disease in a consecutive series of patients is associated with low incidence of adverse events. The reported results are related predominantly to the reduction in repeat revascularization.

Aged↗
PubMed2004

Effectiveness of the sirolimus-eluting stent in the treatment of patients with a prior history of coronary artery bypass graft surgery.

OBJECTIVE: Percutaneous coronary intervention in patients with a history of previous coronary artery bypass grafting (CABG) is associated with an increased rate of subsequent adverse events compared to those without prior CABG. We evaluated the impact of utilizing the sirolimus-eluting stent (SES) in this high-risk population. METHODS: Since April 2002, SES implantation was utilized as the default strategy for all percutaneous procedures in our hospital. Consecutive patients with a history of previous CABG and de novo lesions (n=47) treated exclusively with SES, were compared to 66 patients who received bare stents in the 6-month period just before SES introduction. RESULTS: There were no significant differences between the groups (SES and bare stent) with respect to baseline clinical or lesion characteristics. The only difference between the groups related to the nominal diameter of stent utilized, which was smaller in the SES group than the bare stent group. (The maximum diameter of SES available was 3.0 mm). At 1 year, the cumulative incidence of major adverse events (defined as death, myocardial infarction, or target vessel revascularization) was significantly lower in the SES group than the bare stent group [8.5 versus 30.3%, hazard ratio 0.37 (95% confidence interval 0.15-0.91); P=0.03]. CONCLUSIONS: The utilization of the sirolimus-eluting stent for percutaneous intervention in a high-risk population with a history of previous CABG surgery is associated with a significant reduction in the rate of major adverse cardiac events at 1 year.

Aged↗
PubMed2004

Effectiveness of the sirolimus-eluting stent in the treatment of saphenous vein graft disease.

The use of bare stents for the percutaneous intervention of saphenous vein bypass grafts (SVGs) is associated with a high subsequent rate of restenosis. To assess the impact of the sirolimus-eluting stent (SES), we studied 19 consecutive patients who underwent de novo SVG intervention treated solely with SES. Mean graft age was 10 years. Clinical presentation was an acute coronary syndrome in 68%. In total, twenty-two de novo lesions were treated with 35 SESs (mean=1.6 stents per lesion). Use of glycoprotein IIb/IIIa inhibitor therapy and distal embolization protection device were at operator discretion and were 42% and 32%, respectively. The rate of in-hospital major adverse cardiac events (MACE) was 11%, related to 2 patients with a creatine kinase rise consistent with peri-procedural acute myocardial infarction (AMI); a distal protection device was not utilized in either. Over a mean 12.5+/-2.6 month follow-up, one patient died from a non-cardiac cause, and there were no further AMIs. Target lesion revascularization was undertaken in 1 patient (5%); survival free of MACE was 84%. In conclusion, utilizing SESs for percutaneous intervention of degenerate SVGs is associated with a low rate of target vessel revascularization. Increased utilization of distal protection devices might reduce the peri-procedural rate of AMI.

Acute Disease↗
PubMed2004

Predictors of survival after contemporary percutaneous coronary revascularization for acute myocardial infarction in the real world.

Management strategies for ST-elevation myocardial infarction (STEMI) have undergone great evolution over the past decade. The objectives of this study were to evaluate the in-hospital and long-term clinical outcomes, as well as predictors of survival, among patients who received the most contemporary percutaneous coronary revascularization strategies for STEMI in real clinical practice. During the period from October 1, 2000 to April 30, 2002, 316 patients have undergone primary percutaneous coronary intervention (PCI) in a tertiary University hospital, the in-hospital (11.1%), 30-day (13.9%) and long-term (21.8%) mortality rates were higher than that reported in randomized studies. This is likely to be due to the higher prevalence of adverse clinical profiles. Multivariable analysis show that age >65, cardiogenic shock, resuscitated cardiac arrest and intubation independently predicted in-hospital and long-term mortality, while multi-vessel disease predicted major adverse cardiac event (MACE). Among patients with cardiogenic shock, similar mortality was observed in patients with anterior myocardial infarction (MI) or inferior MI with/without right ventricle involvement.

Age Factors↗
PubMed2003

Unrestricted utilization of sirolimus-eluting stents compared with conventional bare stent implantation in the "real world": the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) registry.

BACKGROUND: The effectiveness of sirolimus-eluting stents in unselected patients treated in the daily practice is currently unknown. METHODS AND RESULTS: Sirolimus-eluting stent implantation has been used as the default strategy for all percutaneous procedures in our hospital as part of the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) registry. Consecutive patients with de novo lesions (n=508) treated exclusively with sirolimus-eluting stents (SES group) were compared with 450 patients who received bare stents in the period just before (pre-SES group). Patients in the SES group more frequently had multivessel disease, more type C lesions, received more stents, and had more bifurcation stenting. At 1 year, the cumulative rate of major adverse cardiac events (death, myocardial infarction, or target vessel revascularization) was 9.7% in the SES group and 14.8% in the pre-SES group (hazard ratio [HR], 0.62 [95% CI, 0.44 to 0.89]; P=0.008). The 1-year risk of clinically driven target vessel revascularization in the SES group and in the pre-SES group was 3.7% versus 10.9%, respectively (HR, 0.35 [95% CI, 0.21 to 0.57]; P<0.001). CONCLUSIONS: Unrestricted utilization of sirolimus-eluting stents in the "real world" is safe and effective in reducing both repeat revascularization and major adverse cardiac events at 1 year compared with bare stent implantation.

Aged↗
PubMed2003

Catheter-based intramyocardial injection of autologous skeletal myoblasts as a primary treatment of ischemic heart failure: clinical experience with six-month follow-up.

OBJECTIVES: We report on the procedural and six-month results of the first percutaneous and stand-alone study on myocardial repair with autologous skeletal myoblasts. BACKGROUND: Preclinical studies have shown that skeletal myoblast transplantation to injured myocardium can partially restore left ventricular (LV) function. METHODS: In a pilot safety and feasibility study of five patients with symptomatic heart failure (HF) after an anterior wall infarction, autologous skeletal myoblasts were obtained from the quadriceps muscle and cultured in vitro for cell expansion. After a culturing process, 296 +/- 199 million cells were harvested (positive desmin staining 55 +/- 30%). With a NOGA-guided catheter system (Biosense-Webster, Waterloo, Belgium), 196 +/- 105 million cells were transendocardially injected into the infarcted area. Electrocardiographic and LV function assessment was done by Holter monitoring, LV angiography, nuclear radiography, dobutamine stress echocardiography, and magnetic resonance imaging (MRI). RESULTS: All cell transplantation procedures were uneventful, and no serious adverse events occurred during follow-up. One patient received an implantable cardioverter-defibrillator after transplantation because of asymptomatic runs of nonsustained ventricular tachycardia. Compared with baseline, the LV ejection fraction increased from 36 +/- 11% to 41 +/- 9% (3 months, p = 0.009) and 45 +/- 8% (6 months, p = 0.23). Regional wall analysis by MRI showed significantly increased wall thickening at the target areas and less wall thickening in remote areas (wall thickening at target areas vs. 3 months follow-up: 0.9 +/- 2.3 mm vs. 1.8 +/- 2.4 mm, p = 0.008). CONCLUSIONS: This pilot study is the first to demonstrate the potential and feasibility of percutaneous skeletal myoblast delivery as a stand-alone procedure for myocardial repair in patients with post-infarction HF. More data are needed to confirm its safety.

Aged↗
PubMed2003

Sirolimus-eluting stent implantation in ST-elevation acute myocardial infarction: a clinical and angiographic study.

BACKGROUND: Sirolimus-eluting stents (SES) have recently been proven to reduce restenosis and reintervention compared with bare stents. Safety and effectiveness of SES in acute myocardial infarction remain unknown. METHODS AND RESULTS: Since April 16, 2002, a policy of routine SES implantation has been instituted in our hospital, with no clinical or anatomic restrictions, as part of the RESEARCH (Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital) registry. During 6 months of enrollment, 96 patients with ST-elevation acute myocardial infarction underwent percutaneous recanalization and SES implantation; these patients comprise the study population. The incidence of major adverse cardiac events (death, nonfatal myocardial infarction, reintervention) was evaluated. Six-month angiographic follow-up was scheduled per protocol. At baseline, diabetes mellitus was present in 12.5% and multivessel disease in 46.9%. Primary angioplasty was performed in 89 patients (92.7%). Infarct location was anterior in 41 (42.7%) of the cases, and 12 patients (12.5%) had cardiogenic shock. Postprocedural TIMI-3 flow was achieved in 93.3% of the cases. In-hospital mortality was 6.2%. One patient (1.1%) had reinfarction and target lesion reintervention the first day as a result of distal dissection and acute vessel occlusion. During follow-up (mean follow-up of 218+/-75 days), 1 patient died (1.1%), no patient had recurrent myocardial infarction, and there were no additional reinterventions. No early or late stent thromboses were documented. At angiographic follow-up (70%), late loss was -0.04+/-0.25, and no patient presented angiographic restenosis. CONCLUSIONS: In this study, sirolimus-eluting stent implantation for patients with ST-elevation acute myocardial infarction was safe without documented angiographic restenosis at 6 months.

Aged↗
PubMed2003

Coronary restenosis after sirolimus-eluting stent implantation: morphological description and mechanistic analysis from a consecutive series of cases.

BACKGROUND: We describe the clinical and morphological patterns of restenosis after sirolimus-eluting stent (SES) implantation. METHODS AND RESULTS: From 121 patients with coronary angiography obtained >30 days after SES implantation, restenosis (diameter stenosis >50%) was identified in 19 patients and 20 lesions (located at the proximal 5-mm segment in 30% or within the stent in 70%). Residual dissection after the procedure or balloon trauma outside the stent was identified in 83% of the proximal edge lesions. Lesions within the stent were focal, and stent discontinuity was identified in some lesions evaluated by intravascular ultrasound. CONCLUSIONS: Sirolimus-eluting stent edge restenosis is frequently associated with local trauma outside the stent. In-stent restenosis occurs as a localized lesion, commonly associated with a discontinuity in stent coverage. Local conditions instead of intrinsic drug-resistance to sirolimus are likely to play a major role in post-SES restenosis.

Adult↗
PubMed2003

Early outcome after sirolimus-eluting stent implantation in patients with acute coronary syndromes: insights from the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) registry.

OBJECTIVES: This study evaluated the early outcomes of patients with acute coronary syndromes (ACS) treated with sirolimus-eluting stents (SES). BACKGROUND: The safety of SES implantation in patients with a high risk for early thrombotic complications is currently unknown. METHODS: Sirolimus-eluting stents have been utilized as the device of choice for all percutaneous procedures in our institution, as part of the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) registry. After four months of enrollment, 198 patients with ACS had been treated exclusively with SES (64% of those treated in the period) and were compared with a control group composed of 301 consecutive patients treated with bare stents in the same time period immediately before this study. The incidence of major adverse cardiac events (MACE) during the first month was evaluated (death, nonfatal myocardial infarction [MI], or re-intervention). RESULTS: Compared with control patients, patients treated with SES had more primary angioplasty (95% vs. 77%; p < 0.01), more bifurcation stenting (13% vs. 5%; p < 0.01), less previous MI (28% vs. 45%; p < 0.01), and less glycoprotein IIb/IIIa inhibitor utilization (27% vs. 42%; p < 0.01). The 30-day MACE rate was similar between both groups (SES 6.1% vs. control patients 6.6%; p = 0.8), with most complications occurring during the first week. Stent thrombosis occurred in 0.5% of SES patients and in 1.7% of control patients (p = 0.4). In multivariate analysis, SES utilization did not influence the incidence of MACE (odds ratio 1.0 [95% confidence interval: 0.4 to 2.2]; p = 0.97). CONCLUSIONS: Sirolimus-eluting stent implantation for patients with ACS is safe, with early outcomes comparable with bare metal stents.

Acute Disease↗
PubMed2003

TAXUS III Trial: in-stent restenosis treated with stent-based delivery of paclitaxel incorporated in a slow-release polymer formulation.

BACKGROUND: The first clinical study of paclitaxel-eluting stent for de novo lesions showed promising results. We performed the TAXUS III trial to evaluate the feasibility and safety of paclitaxel-eluting stent for the treatment of in-stent restenosis (ISR). METHODS AND RESULTS: The TAXUS III trial was a single-arm, 2-center study that enrolled 28 patients with ISR meeting the criteria of lesion length < or =30 mm, 50% to 99% diameter stenosis, and vessel diameter 3.0 to 3.5 mm. They were treated with one or more TAXUS NIRx paclitaxel-eluting stents. Twenty-five patients completed the angiographic follow-up at 6 months, and 17 of these underwent intravascular ultrasound (IVUS) examination. No subacute stent thrombosis occurred up to 12 months, but there was one late chronic total occlusion, and additional 3 patients showed angiographic restenosis. The mean late loss was 0.54 mm, with neointimal hyperplasia volume of 20.3 mm3. The major adverse cardiac event rate was 29% (8 patients; 1 non-Q-wave myocardial infarction, 1 coronary artery bypass grafting, and 6 target lesion revascularization [TLR]). Of the patients with TLR, 1 had restenosis in a bare stent implanted for edge dissection and 2 had restenosis in a gap between 2 paclitaxel-eluting stents. Two patients without angiographic restenosis underwent TLR as a result of the IVUS assessment at follow-up (1 incomplete apposition and 1 insufficient expansion of the stent). CONCLUSIONS: Paclitaxel-eluting stent implantation is considered safe and potentially efficacious in the treatment of ISR. IVUS guidance to ensure good stent deployment with complete coverage of target lesion may reduce reintervention.

Antineoplastic Agents, Phytogenic↗
PubMed2003

Sirolimus-eluting stent for treatment of complex in-stent restenosis: the first clinical experience.

OBJECTIVES: In this study, we assess the value of sirolimus eluting stent (SES) implantation in patients with complex in-stent restenosis (ISR). BACKGROUND: The treatment of ISR remains a therapeutic challenge, since many pharmacological and mechanical approaches have shown disappointing results. The SESs have been reported to be effective in de-novo coronary lesions. METHODS: Sixteen patients with severe, recurrent ISR in a native coronary artery (average lesion length 18.4 mm) and objective evidence of ischemia were included. They received one or more 18 mm Bx VELOCITY SESs (Cordis Waterloo, Belgium). Quantitative angiographic and three-dimensional intravascular ultrasound (IVUS) follow-up was performed at four months, and clinical follow-up at nine months. RESULTS: The SES implantation (n = 26) was successful in all 16 patients. Four patients had recurrent restenosis following brachytherapy, and three patients had totally occluded vessels preprocedure. At four months follow-up, one patient had died and three patients had angiographic evidence of restenosis (one in-stent and two in-lesion). In-stent late lumen loss averaged 0.21 mm and the volume obstruction of the stent by IVUS was 1.1%. At nine months clinical follow-up, three patients had experienced four major adverse cardiac events (two deaths and one acute myocardial infarction necessitating repeat target vessel angioplasty). CONCLUSIONS: The SES implantation in patients with severe ISR lesions effectively prevents neointima formation and recurrent restenosis at four months angiographic follow-up.

Adult↗
PubMed2003

Collateral formation in patients after percutaneous myocardial revascularization: a mechanism for improvement?

BACKGROUND: Percutaneous myocardial revascularization (PMR) has emerged as a novel therapeutic strategy for patients with ischemic heart disease not amendable to traditional revascularization approaches. Despite the symptomatic improvement documented in clinical trials, underlying mechanism remains unknown. METHODS: We assessed the coronary angiograms of 25 patients before and 6 months after the PMR procedures for collateral vessel formation. The Rentrop scoring system was used to score the extent of collateral vessel formation. The angiograms were analyzed by 2 independent reviewers. The change in Rentrop score and improvement in angina status was correlated. RESULTS: During follow-up period of 6 months, no patient died or suffered from myocardial infarction. Overall the mean Canadian Classification Society (CCS) class among the study patients was significantly improved from 3.5 to 2.4; mean difference = 1.08 (p < 0.0001). Among these, 8 (32%) had improvement of > 2 CCS classes (p = 0.003) (improvement group). The rest of the patients had either no change (n = 8; 32%) or improvement of 1 CCS class (n = 9; 36%) (no improvement group). The Rentrop score improved in 3 (12%), remained unchanged in 22 (88%) and deteriorated in 0 patient. Overall, there was no significant change in Rentrop score at 6-month follow-up; mean difference 0.13 (p = 0.08). There was also no correlation between the change in extent of collateral vessel formation and the improvement in angina status (correlation coefficient r = 0.09) at 6 months after PMR. CONCLUSION: Improvement in collateral vessel formation is unlikely to be a mechanism responsible for symptomatic improvement in patients after PMR.

Aged↗
PubMed2002

Efficacy of percutaneous intramyocardial injections using a nonfluoroscopic 3-D mapping based catheter system.

BACKGROUND: Percutaneous transendomyocardial injection with an injection catheter is a new drug delivery method for e.g. therapeutic angiogenesis. Little is known about the efficacy of this drug delivery technique. We studied efficiency and retention of transendomyocardial injections with a NOGA guided injection catheter system by using scintigraphy with radio-labeled model drugs. METHODS: Ten non-ischemic landrace pigs were used. In each animal 2-3 transendomyocardial injections were performed using a 3-D mapping based catheter system called NOGA. As a model for proteins like angiogenic growth factors we used (99m)Tc labeled albumin and as a model for small particles like microspheres or adenovirus we used (99m)Tc labeled colloid albumin. Efficiency of the injections and retention of the transendomyocardial deposited substance were evaluated by a gamma camera during and after injection of 0.1 or 0.2 ml. RESULTS: All 29 injections showed scintigraphic proof of intramyocardial deposition. The average injection efficiency of all 29 injections was 26 +/- 23%. The average injection efficiency of 0.1 and 0.2 ml injections were 33 +/- 30% (n = 8) and 24 +/- 20% (n = 21), respectively (p = 0.33). Intramyocardial retention curves of albumin showed a rapid wash-out within the first 2 hours of the injection, whereas the retention of colloid albumin showed no decrease. In conclusion, transendomyocardial delivery of proteins or particles with an injection catheter show favorable efficiency rates, however the retention time of intramyocardial deposited small proteins like albumin is short. This may indicate the need for sustained release systems of angiogenic growth factors for intramyocardal injection in therapeutic angiogenesis.

Albumins↗