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Featured researches published by Pedro A. Lemos.


Circulation | 2002

Reliable Noninvasive Coronary Angiography With Fast Submillimeter Multislice Spiral Computed Tomography

Koen Nieman; Filippo Cademartiri; Pedro A. Lemos; Rolf Raaijmakers; Peter M. T. Pattynama; Pim J. de Feyter

Background—Multislice spiral computed tomography (MSCT) is a promising technique for noninvasive coronary angiography, although clinical application has remained limited because of frequently incomplete interpretability, caused by motion artifacts and calcifications. Methods and Results—In 59 patients (53 male, aged 58±12 years) with suspected obstructive coronary artery disease, ECG-gated MSCT angiography was performed with a 16-slice MSCT scanner (0.42-s rotation time, 12×0.75-mm detector collimation). Thirty-four patients were given additional &bgr;-blockers (average heart rate: 56±6 min−1). After contrast injection, all data were acquired during an approximately 20-s breath hold. The left main (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA), including ≥2.0-mm side branches, were independently evaluated by two blinded observers and screened for ≥50% stenoses. The consensus reading was compared with quantitative coronary angiography. MSCT was successful in 58 patients. Eighty-six of the 231 evaluated branches were significantly diseased. Without exclusion of branches, the sensitivity, specificity and positive and negative predictive value to identify ≥50% obstructed branches was 95% (82/86), 86% (125/145), 80% (82/102), and 97% (125/129), respectively. The overall accuracy for the LM, LAD, RCA, and LCX was 100%, 91%, 86%, and 81%, respectively. No obstructed LM, LAD, or RCA branches remained undetected. Classification of patients as having no, single, or multivessel disease was accurate in 78% (45/58) of patients and no patients with significant obstructions were incorrectly excluded. Conclusions—Improvements in MSCT technology, combined with heart rate control, allow reliable noninvasive detection of obstructive coronary artery disease.


Circulation | 2004

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

Pedro A. Lemos; Patrick W. Serruys; Ron T. van Domburg; Francesco Saia; Chourmouzios A. Arampatzis; Angela Hoye; Muzaffer Degertekin; Kengo Tanabe; Joost Daemen; Tommy K.K. Liu; Eugene McFadden; Georgios Sianos; Sjoerd H. Hofma; Pieter C. Smits; Willem J. van der Giessen; Pim J. de Feyter

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 R apamycin-E luting S tent E valuated A t R otterdam C ardiology H ospital (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.


Journal of the American College of Cardiology | 2013

Incidence, Predictors, and Outcomes of Aortic Regurgitation After Transcatheter Aortic Valve Replacement Meta-Analysis and Systematic Review of Literature

Ganesh Athappan; Eshan Patvardhan; E. Murat Tuzcu; Lars Georg Svensson M.D.; Pedro A. Lemos; Chiara Fraccaro; Giuseppe Tarantini; Jan Malte Sinning; Georg Nickenig; Davide Capodanno; Corrado Tamburino; Azeem Latib; Antonio Colombo; Samir Kapadia

OBJECTIVES This study was designed to establish the incidence, impact, and predictors of post-transcatheter aortic valve replacement (TAVR) aortic regurgitation (AR). BACKGROUND AR is an important limitation of TAVR with ill-defined predictors and unclear long-term impact on outcomes. METHODS Studies published between 2002 and 2012 with regard to TAVR were identified using an electronic search and reviewed using the random-effects model of DerSimonian and Laird. From 3,871 initial citations, 45 studies reporting on 12,926 patients (CoreValve [Medtronic CV Luxembourg S.a.r.l., Tolochenaz, Switzerland] n = 5,261 and Edwards valve [Edwards Lifesciences, Santa Ana, California] n = 7,279) were included in the analysis of incidence and outcomes of post-TAVR AR. RESULTS The pooled estimate for moderate or severe AR post-TAVR was 11.7% (95% confidence interval [CI]: 9.6 to 14.1). Moderate or severe AR was more common with use of the CoreValve (16.0% vs. 9.1%, p = 0.005). The presence of moderate or severe AR post-TAVR increased mortality at 30 days (odds ratio: 2.95; 95% CI: 1.73 to 5.02) and 1 year (hazard ratio: 2.27; 95% CI: -1.84 to 2.81). Mild AR was also associated with an increased hazard ratio for mortality, 1.829 (95% CI: 1.005 to 3.329) that was overturned by sensitivity analysis. Twenty-five studies reported on predictors of post-TAVR AR. Implantation depth, valve undersizing, and Agatston calcium score (r = 0.47, p = 0.001) were identified as important predictors. CONCLUSIONS Moderate or severe aortic regurgitation is common after TAVR and an adverse prognostic indicator of short- and long-term survival. Incidence of moderate or severe AR is higher with use of the CoreValve. Mild AR may be associated with increased long-term mortality. Therefore, every effort should be made to minimize AR by a comprehensive pre-procedural planning and meticulous procedural execution.


Circulation | 2004

Clinical, Angiographic, and Procedural Predictors of Angiographic Restenosis After Sirolimus-Eluting Stent Implantation in Complex Patients An Evaluation From the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) Study

Pedro A. Lemos; Angela Hoye; Dick Goedhart; Chourmouzios A. Arampatzis; Francesco Saia; Willem J. van der Giessen; Eugene McFadden; Georgios Sianos; Pieter C. Smits; Sjoerd H. Hofma; Pim J. de Feyter; Ron T. van Domburg; Patrick W. Serruys

Background—The factors associated with the occurrence of restenosis after sirolimus-eluting stent (SES) implantation in complex cases are currently unknown. Methods and Results—A cohort of consecutive complex patients treated with SES implantation was selected according to the following criteria: (1) treatment of acute myocardial infarction, (2) treatment of in-stent restenosis, (3) 2.25-mm diameter SES, (4) left main coronary stenting, (5) chronic total occlusion, (6) stented segment >36 mm, and (7) bifurcation stenting. The present study population was composed of 238 patients (441 lesions) for whom 6-month angiographic follow-up data were obtained (70% of eligible patients). Significant clinical, angiographic, and procedural predictors of post-SES restenosis were evaluated. Binary in-segment restenosis was diagnosed in 7.9% of lesions (6.3% in-stent, 0.9% at the proximal edge, 0.7% at the distal edge). The following characteristics were identified as independent multivariate predictors: treatment of in-stent restenosis (OR 4.16, 95% CI 1.63 to 11.01; P <0.01), ostial location (OR 4.84, 95% CI 1.81 to 12.07; P <0.01), diabetes (OR 2.63, 95% CI 1.14 to 6.31; P =0.02), total stented length (per 10-mm increase; OR 1.42, 95% CI 1.21 to 1.68; P <0.01), reference diameter (per 1.0-mm increase; OR 0.46, 95% CI 0.24 to 0.87; P =0.03), and left anterior descending artery (OR 0.30, 95% CI 0.10 to 0.69; P <0.01). Conclusions—Angiographic restenosis after SES implantation in complex patients is an infrequent event, occurring mainly in association with lesion-based characteristics and diabetes mellitus.


Circulation | 2003

Coronary Restenosis After Sirolimus-Eluting Stent Implantation Morphological Description and Mechanistic Analysis From a Consecutive Series of Cases

Pedro A. Lemos; Francesco Saia; Jurgen Ligthart; Chourmouzios A. Arampatzis; Georgios Sianos; Kengo Tanabe; Angela Hoye; Muzaffer Degertekin; Joost Daemen; Eugene McFadden; Sjoerd H. Hofma; Pieter C. Smits; Pim J. de Feyter; Willem J. van der Giessen; Ron T. van Domburg; Patrick W. Serruys

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. (Circulation. 2003; 108:257‐260.)


Circulation | 2008

Long-Term Safety and Efficacy of Percutaneous Coronary Intervention With Stenting and Coronary Artery Bypass Surgery for Multivessel Coronary Artery Disease: A Meta-Analysis With 5-Year Patient-Level Data From the ARTS, ERACI-II, MASS-II, and SoS Trials

Joost Daemen; Eric Boersma; Marcus Flather; Jean Booth; Rod Stables; Alfredo E. Rodriguez; Gaston A. Rodriguez-Granillo; Whady Hueb; Pedro A. Lemos; Patrick W. Serruys

Background— Randomized trials that studied clinical outcomes after percutaneous coronary intervention (PCI) with bare metal stenting versus coronary artery bypass grafting (CABG) are underpowered to properly assess safety end points like death, stroke, and myocardial infarction. Pooling data from randomized controlled trials increases the statistical power and allows better assessment of the treatment effect in high-risk subgroups. Methods and Results— We performed a pooled analysis of 3051 patients in 4 randomized trials evaluating the relative safety and efficacy of PCI with stenting and CABG at 5 years for the treatment of multivessel coronary artery disease. The primary end point was the composite end point of death, stroke, or myocardial infarction. The secondary end point was the occurrence of major adverse cardiac and cerebrovascular accidents, death, stroke, myocardial infarction, and repeat revascularization. We tested for heterogeneities in treatment effect in patient subgroups. At 5 years, the cumulative incidence of death, myocardial infarction, and stroke was similar in patients randomized to PCI with stenting versus CABG (16.7% versus 16.9%, respectively; hazard ratio, 1.04, 95% confidence interval, 0.86 to 1.27; P=0.69). Repeat revascularization, however, occurred significantly more frequently after PCI than CABG (29.0% versus 7.9%, respectively; hazard ratio, 0.23; 95% confidence interval, 0.18 to 0.29; P<0.001). Major adverse cardiac and cerebrovascular events were significantly higher in the PCI than the CABG group (39.2% versus 23.0%, respectively; hazard ratio, 0.53; 95% confidence interval, 0.45 to 0.61; P<0.001). No heterogeneity of treatment effect was found in the subgroups, including diabetic patients and those presenting with 3-vessel disease. Conclusions— In this pooled analysis of 4 randomized trials, PCI with stenting was associated with a long-term safety profile similar to that of CABG. However, as a result of persistently lower repeat revascularization rates in the CABG patients, overall major adverse cardiac and cerebrovascular event rates were significantly lower in the CABG group at 5 years.


Circulation | 2003

Drug-Eluting Stents Cost Versus Clinical Benefit

Pedro A. Lemos; Patrick W. Serruys; J. Eduardo Sousa

The publication in January 2001 of the first-in-man results showing zero restenosis after sirolimus-eluting stent implantation produced enormous excitement in the cardiological community.1 The long-awaited tool—a safe, restenosis-proof, easy-to-use stent—had been found. It was not too long thereafter that paclitaxel-eluting stents also demonstrated their capability to decrease restenosis. Today, both sirolimus- and paclitaxel-eluting stents have been shown in randomized trials to reduce restenosis as compared with conventional metallic stents (Figure 1).2–6 Most of these studies have been recently released in the form of abstracts during medical meetings and are still unpublished.3,5,6 In addition to sirolimus and paclitaxel, other agents have shown promising early results in recent studies, enlarging the body of evidence demonstrating the potential benefits of what are known as drug-eluting stents.7 Regulatory agencies have been very active in evaluating some of these devices in the United States, Europe, South America, and Asia. The sirolimus-eluting stent has been available for routine use in Europe, South America, and Asia since the first half of 2002 and received approval from the US Food and Drug Administration to be marketed in April 2003. Paclitaxel-eluting stents have also received CE (Conformite Europeenne) marking for commercialization in Europe and are now beginning to be commercialized. Figure 1. Randomized trials showing reduction of binary restenosis with drug-eluting stents.2–6 The case seemed to be closed. Restenosis, the Achilles’ heel of percutaneous revascularization, appeared defeated. However, since the sirolimus-eluting stents became available, very little has changed in the everyday life of almost all interventional laboratories in Europe. Why? Has the new treatment presented any undesirable effect? Was the desire to defeat restenosis not as great as supposed? The answer is none of the above. The limitation currently impeding more widespread use of the new technology is nontechnical, nonmedical, and nonbiological. The …


Catheterization and Cardiovascular Interventions | 2004

Stent fracture and restenosis in the drug-eluting stent era.

Georgios Sianos; Sjoerd H. Hofma; Jurgen Ligthart; Francesco Saia; Angela Hoye; Pedro A. Lemos; Patrick W. Serruys

Coronary stents, initially reserved for bailout situations, are now used in more than 80% of all cases. However, their efficacy is limited by the occurrence of in-stent restenosis, ranging from 15% to 35% of cases, depending on lesion morphology [1–3]. Recently, drugeluting stents have been proven very effective in suppressing neointimal proliferation and reduced restenosis to single digit numbers [4–6]. We report two cases of treatment failure with sirolimus-eluting stents (SESs) related to stent fractures.


Journal of the American College of Cardiology | 2003

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

Pedro A. Lemos; Chi-Hang Lee; Muzaffer Degertekin; Francesco Saia; Kengo Tanabe; Chourmouzios A. Arampatzis; Angela Hoye; Marco van Duuren; Sianos G; Pieter C. Smits; Pim J. de Feyter; Willem J. van der Giessen; Ron T. van Domburg; Patrick W. Serruys

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.


Jacc-cardiovascular Interventions | 2011

Feasibility of Transcatheter Aortic Valve Implantation Without Balloon Pre-Dilation: A Pilot Study

Eberhard Grube; Christoph Naber; Alexandre Abizaid; Eduardo Sousa; Oscar Mendiz; Pedro A. Lemos; Roberto Kalil Filho; José Armando Mangione; Lutz Buellesfeld

OBJECTIVES The purpose of this pilot study was to evaluate the feasibility and safety of transcatheter aortic valve implantation (TAVI) without balloon pre-dilation. BACKGROUND Balloon pre-dilation of the stenosed aortic valve is currently believed to be a necessary step for valve preparation before device placement in patients undergoing TAVI and, therefore, is considered an obligatory part of the procedure. However, clear evidence supporting this policy is lacking. In contrast, pre-dilation might be responsible in part for distal embolizations as well as atrioventricular conduction disturbances seen during TAVI procedures. METHODS A total of 60 consecutive patients (mean age 80.1 ± 6.4 years, 53% female, mean logistic EuroScore 23.3 ± 15.2%) undergoing TAVI using the self-expanding Medtronic CoreValve prosthesis (Medtronic, Minneapolis, Minnesota) have been prospectively enrolled at 13 international centers. RESULTS Pre-procedural mean transaortic valve gradient was 47.8 ± 15.5 mm Hg, mean effective orifice area was 0.67 ± 0.15 cm(2). Technical success rate was 96.7% (58 of 60) of patients. Post-dilation was performed in 16.7% (10 of 60) of patients. Post-procedural mean valve gradient was 4.4 ± 2.0 mm Hg. Circular and noncircular valve configuration was present in 41 and 19 cases (68.3% vs. 31.7%), respectively, with similar effective orifice areas (1.74 ± 0.10 cm(2) vs. 1.71 ± 0.22 cm(2), p = NS). In-hospital mortality, myocardial infarction, stroke, and major vascular complications occurred in 6.7% (4 of 60), 0%, 5%, and 10% of patients. There was no valve embolization. New permanent pacing was needed in 11.7% (7 of 60) of patients. CONCLUSIONS Transcatheter aortic valve implantation without balloon pre-dilation is feasible and safe, resulting in similar acute safety and efficacy as the current standard approach of TAVI with pre-dilation.

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Pim J. de Feyter

Erasmus University Rotterdam

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Alexandre Abizaid

MedStar Washington Hospital Center

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Ron T. van Domburg

Erasmus University Rotterdam

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Pieter C. Smits

Erasmus University Rotterdam

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