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Featured researches published by C Seiler.


Heart | 2004

Percutaneous closure of patent foramen ovale: impact of device design on safety and efficacy

Markus Schwerzmann; S Windecker; Andreas Wahl; H Mehta; Krassen Nedeltchev; Heinrich P. Mattle; C Seiler; B Meier

Objective: To compare the safety and efficacy of percutaneous closure of patent foramen ovale (PFO) with the Amplatzer PFO occluder (Amplatzer) or the PFO STAR device (STAR) in patients with presumed paradoxical embolism. Methods: Implantation characteristics, procedural complications, residual shunt, and recurrence of thromboembolic events were recorded prospectively in 100 consecutive patients undergoing percutaneous PFO closure with the STAR (n u200a=u200a 50) or Amplatzer (n u200a=u200a 50) devices between 1998 and 2001. The study was not randomised. Device implantation was successful in all cases. Results: There were more procedural complications in the STAR than in the Amplatzer group (8/50 v 1/50, p u200a=u200a 0.01). More than one device placement attempt was an independent predictor of procedural complications (odds ratio (OR) 8.5, 95% confidence interval (CI) 1.3 to 55.8; p u200a=u200a 0.03). A residual shunt six months after PFO closure, assessed by transoesophageal contrast echocardiography, occurred more often in the STAR than the Amplatzer group (17/50 v 3/50, p u200a=u200a 0.004), and was predicted in the STAR group by the use of a device with a 5 mm as opposed to a 3 mm disc connector (OR 6.1, 95% CI 1.1 to 34.0; p u200a=u200a 0.04). The actuarial risk of recurrent thromboembolic events after 3.5 years was 16.8% (95% CI 7.6% to 34.6%) in the STAR and 2.7% (95% CI 0.4% to 17.7%) in the Amplatzer group after three years (p u200a=u200a 0.08). Conclusions: Percutaneous PFO closure with the Amplatzer PFO occluder had fewer procedural complications and was more likely to be complete than with the STAR device. These findings underline the importance of device design for successful percutaneous PFO closure.


Journal of the American College of Cardiology | 2011

Long-Term Comparison of Everolimus-Eluting and Sirolimus-Eluting Stents for Coronary Revascularization

Lorenz Räber; Peter Jüni; Eveline Nüesch; Bindu Kalesan; Peter Wenaweser; Aris Moschovitis; Ahmed A. Khattab; Maryam Bahlo; Mario Togni; Stéphane Cook; Rolf Vogel; C Seiler; Bernhard Meier; Stephan Windecker

OBJECTIVESnThis study sought to compare the unrestricted use of everolimus-eluting stents (EES) with sirolimus-eluting stents (SES) in patients undergoing percutaneous coronary intervention.nnnBACKGROUNDnIt is unclear whether there are differences in safety and efficacy between EES and SES during long-term follow-up.nnnMETHODSnUsing propensity score matching, clinical outcome was compared among 1,342 propensity score-matched pairs of patients treated with EES and SES. The primary outcome was a composite of death, MI, and target vessel revascularization.nnnRESULTSnThe median follow-up was 1.5 years with a maximum of 3 years. The primary outcome occurred in 14.9% of EES- and 18.0% of SES-treated patients up to 3 years (hazard ratio [HR]: 0.83, 95% confidence interval [CI]: 0.68 to 1.00, p = 0.056). All-cause mortality (6.0% vs. 6.5%, HR: 0.92, 95% CI: 0.68 to 1.25, p = 0.59) was similar, risks of myocardial infarction (MI) (3.3% vs. 5.0%, HR: 0.62, 95% CI: 0.42 to 0.92, p = 0.017), and target vessel revascularization (7.0% vs. 9.6%, HR: 0.75, 95% CI: 0.57 to 0.99, p = 0.039) were lower with EES than SES. Definite stent thrombosis (ST) (HR: 0.30, 95% CI: 0.12 to 0.75, p = 0.01) was less frequent among patients treated with EES. The reduced rate of MI with EES was explained in part by the lower risk of definite ST and the corresponding decrease in events associated with ST (HR: 0.25, 95% CI: 0.08 to 0.75, p = 0.013).nnnCONCLUSIONSnThe unrestricted use of EES appears to be associated with improved clinical long-term outcome compared with SES. Differences in favor of EES are driven in part by a lower risk of MI associated with ST.


Journal of the American College of Cardiology | 2010

Impact of stent overlap on angiographic and long-term clinical outcome in patients undergoing drug-eluting stent implantation.

Lorenz Räber; Peter Jüni; Lukas M. Löffel; Simon Wandel; Stéphane Cook; Peter Wenaweser; Mario Togni; Rolf Vogel; C Seiler; Franz R. Eberli; Thomas F. Lüscher; Bernhard Meier; Stephan Windecker

OBJECTIVESnWe compared the angiographic and long-term clinical outcomes of patients with and without overlap of drug-eluting stents (DES).nnnBACKGROUNDnDES overlap has been associated with delayed healing and increased inflammation in experimental studies, but its impact on clinical outcome is not well established.nnnMETHODSnWe analyzed the angiographic and clinical outcomes of 1,012 patients treated with DES in the SIRTAX (Sirolimus-Eluting Versus Paclitaxel-Eluting Stents for Coronary Revascularization) trial according to the presence or absence of stent overlap and the number of stents per vessel: 134 (13.2%) patients with multiple DES in a vessel with overlap, 199 (19.7%) patients with multiple DES in a vessel without overlap, and 679 (67.1%) patients with 1 DES per vessel.nnnRESULTSnAngiographic follow-up at 8 months showed an increased late loss in DES overlap patients (0.33 +/- 0.61 mm) compared with the other groups (0.18 +/- 0.43 mm and 0.15 +/- 0.38 mm, p < 0.01). The smallest minimal lumen diameter was located at the zone of stent overlap in 17 (68%) of 25 patients with stent overlap who underwent target lesion revascularization. Major adverse cardiac events were more common in patients with DES overlap (34 events, 25.4%) than in the other groups (42 events, 21.1% and 95 events, 14.0%) at 3 years (p < 0.01). Both the risk of target lesion revascularization (20.2% vs. 16.1% vs. 9.7%, p < 0.01) and the composite of death or myocardial infarction (17.2% vs. 14.1% vs. 9.1%, p = 0.01) were increased in patients with DES overlap compared with the other groups.nnnCONCLUSIONSnDES overlap occurs in >10% of patients undergoing percutaneous coronary intervention in routine clinical practice and is associated with impaired angiographic and long-term clinical outcome, including death or myocardial infarction. (Sirolimus-Eluting Versus Paclitaxel-Eluting Stents for Coronary Revascularization; NCT00297661).


European Heart Journal | 2012

Impact of incomplete stent apposition on long-term clinical outcome after drug-eluting stent implantation

Stéphane Cook; Parham Eshtehardi; Bindu Kalesan; Lorenz Räber; Peter Wenaweser; Mario Togni; Aris Moschovitis; Rolf Vogel; C Seiler; Franz R. Eberli; Thomas F. Lüscher; Bernhard Meier; Peter Jüni; Stephan Windecker

AIMSnLate acquired incomplete stent apposition (ISA) is more common after drug-eluting stent (DES) than bare metal stent (BMS) implantation and has been associated with vascular hypersensitivity and stent thrombosis (ST). We investigated the impact of incidentally discovered ISA as assessed by intravascular ultrasound (IVUS) 8 months after DES implantation on the long-term clinical outcome.nnnMETHODS AND RESULTSnA total of 194 patients with 221 lesions were prospectively followed through 5 years. At 8 months, IVUS showed evidence of ISA among 37 patients with 39 lesions (18%) (mean ISA(max) 4.7 ± 5.0 mm(2)), whereas no ISA was observed among 157 patients with 182 lesions. Incomplete stent apposition was more prevalent among segments treated with sirolimus-eluting (n = 103) than paclitaxel-eluting stents (n = 118) (27 vs. 9%, P = 0.001). Between IVUS investigation at the 8-month and 5-year follow-up, major adverse cardiac events occurred more frequently in patients with (18.9%, n = 7) than without ISA (7.0%, n = 11) (HR = 2.71, 95% CI: 1.05-6.96, P = 0.031). While there were no differences with respect to death, the rate of myocardial infarction was higher among patients with (13.5%, n = 5) than without ISA (1.9%, n = 3) (HR = 7.53, 95% CI: 1.79-31.6, P = 0.001). Very late ST was more common among patients with than without ISA [Academic Research Consortium-definite ST:13.5% (n = 5) vs. 0.6% (n = 1) HR = 23.2, 95% CI: 2.65-203, P < 0.001].nnnCONCLUSIONnIn the present study, the presence of ISA as assessed by IVUS 8 months after DES implantation was associated with a higher rate of myocardial infarction and very late stent thrombosis during long-term follow-up. The prognostic impact of ISA on long-term clinical outcomes requires further investigation.


Heart | 2000

Relaxation in hypertrophic cardiomyopathy and hypertensive heart disease: relations between hypertrophy and diastolic function

S F de Marchi; Yves Allemann; C Seiler

AIM To determine the relation between the extent and distribution of left ventricular hypertrophy and the degree of disturbance of regional relaxation and global left ventricular filling. METHODS Regional wall thickness (rWT) was measured in eight myocardial regions in 17 patients with hypertrophic cardiomyopathy, 12 patients with hypertensive heart disease, and 10 age matched normal subjects, and an asymmetry index calculated. Regional relaxation was assessed in these eight regions using regional isovolumetric relaxation time (rIVRT) and early to late peak filling velocity ratio (rE/A) derived from Doppler tissue imaging. Asynchrony of rIVRT was calculated. Doppler left ventricular filling indices were assessed using the isovolumetric relaxation time, the deceleration time of early diastolic filling (E-DT), and the E/A ratio. RESULTS There was a correlation between rWT and both rIVRT and rE/A in the two types of heart disease (hypertrophic cardiomyopathy: ru2009=u20090.47, pu2009<u20090.0001 for rIVRT; ru2009=u2009−0.20, pu2009<u20090.05 for rE/A; hypertensive heart disease:ru2009=u20090.21, pu2009<u20090.05 for rIVRT;ru2009=u2009−0.30, pu2009=u20090.003 for rE/A). The degree of left ventricular asymmetry was related to prolonged E-DT (ru2009=u20090.50, pu2009=u20090.001) and increased asynchrony (ru2009=u20090.42, pu2009=u20090.002) in all patients combined, but not within individual groups. Asynchrony itself was associated with decreased E/A (ru2009=u2009−0.39, pu2009=u20090.01) and protracted E-DT (ru2009=u20090.69, pu2009<u20090.0001) and isovolumetric relaxation time (ru2009=u20090.51, pu2009=u20090.001) in all patients. These correlations were still significant for E-DT in hypertrophic cardiomyopathy (ru2009=u20090.56, pu2009=u20090.02) and hypertensive heart disease (ru2009=u20090.59, pu2009<u20090.05) and for isovolumetric relaxation time in non-obstructive hypertrophic cardiomyopathy (nu2009=u20098, ru2009=u20090.87, pu2009=u20090.005). CONCLUSIONS Non-invasive ultrasonographic examination of the left ventricle shows that in both hypertrophic cardiomyopathy and hypertensive heart disease, the local extent of left ventricular hypertrophy is associated with regional left ventricular relaxation abnormalities. Asymmetrical distribution of left ventricular hypertrophy is indirectly related to global left ventricular early filling abnormalities through regional asynchrony of left ventricular relaxation.


Heart | 2001

Pulmonary venous flow velocity patterns in 404 individuals without cardiovascular disease

S F de Marchi; M Bodenmüller; D L Lai; C Seiler

OBJECTIVE To determine the pulmonary venous flow velocity (PVFV) values in a large normal population. DESIGN Prospective study in consecutive individuals. SETTING University hospital. METHODS Among 404 normal individuals, the flow velocity pattern in the right upper pulmonary vein was recorded in 315 subjects using transthoracic echocardiography, and in both upper pulmonary veins in 100 subjects using transoesophageal echocardiography. Subjects were divided into five age groups. The PVFV values were compared between transthoracic and transoesophageal echocardiography within the age groups, and intraindividually between the right and left upper pulmonary veins in transoesophageal echocardiography. RESULTS Normal PVFV values for the right upper pulmonary vein in transthoracic and transoesophageal echocardiography are presented. The duration of flow reversal at atrial contraction was overestimated using transthoracic echocardiography (mean (SD): 96 (21)u2009ms in transoesophageal echocardiography, 120 (28)u2009ms in transthoracic echocardiography, pu2009<u20090.0001). Systolic to diastolic peak flow velocity ratio (S:D) increased earlier with advancing age with transoesophageal echocardiography than with transthoracic echocardiography. Similar results were found for the corresponding time–velocity integrals. Data from the left and right upper pulmonary veins differed with respect to onset and deceleration of flow velocities, but not for flow durations or peak velocities. CONCLUSIONS Normal PVFV values generally show a wide range. The data presented will be of value in assessing left ventricular diastolic function and mitral regurgitation using the PVFV pattern.


Transplant International | 2006

Effect of donor-specific transfusions on the outcome of renal allografts in the cyclosporine era

Hans-Peter Marti; Jana Henschkowski; Gunter Laux; Bruno Vogt; C Seiler; Gerhard Opelz; Felix J. Frey

Despite the introduction of new immunosuppressive agents, a steady decline of functioning renal allografts after living donation is observed. Thus nonpharmacological strategies to prevent graft loss have to be reconsidered, including donor‐specific transfusions (DST). We introduced a cyclosporine‐based DST protocol for renal allograft recipients from living‐related/unrelated donation. From 1993 to 2003, 200u2003ml of whole blood, or the respective mononuclear cells from the potential living donor were administered twice to all of our 61 recipient candidates. The transplanted subjects were compared with three groups of patients without DST from the Collaborative Transplant Study (Heidelberg, Germany) during a 6‐year period. Six patients were sensitized without delay for a subsequent cadaveric kidney. DST patients had less often treatment for rejection and graft survival was superior compared with subjects from the other Swiss transplant centers (nu2003=u2003513) or from Western Europe (nu2003=u20037024). To diminish the probability that superior results reflect patient selection rather than effects of DST, a ‘matched‐pair’ analysis controlling for relevant factors of transplant outcome was performed. Again, this analysis indicated that recipients with DST had better outcome. Thus, our observation suggests that DST improve the outcome of living kidney transplants even when modern immunosuppressive drugs are prescribed.


Heart | 1995

Left ventricular chamber dilatation in hypertrophic cardiomyopathy: related variables and prognosis in patients with medical and surgical therapy.

C Seiler; Rolf Jenni; G. Vassalli; Marko Turina; O. M. Hess

BACKGROUND--To determine the incidence and prognosis of left ventricular dilatation and systolic dysfunction in 139 patients with hypertrophic cardiomyopathy during long term follow up. METHODS--Left ventricular chamber dilatation and systolic dysfunction (both together referred to as left ventricular chamber dilatation) were determined echocardiographically. Chamber dilatation was defined as an increase in the left ventricular end diastolic diameter of > 2% per year combined with a decrease in midventricular systolic fractional shortening of > 2% per year of follow up [10.3 (SD 6) years]. The predictive value for left ventricular chamber dilatation of clinical, invasive, and echocardiographic variables and its prognosis were assessed. RESULTS--In 119 of 139 individuals (86%), left ventricular chamber size and systolic function remained stable (group 1), and in 20/139 patients (14%) left ventricular chamber dilatation occurred during follow up (group 2). At baseline examination, symptoms such as dyspnoea and syncope occurred less often in group 1 than in group 2; New York Heart Association classification was lower in group 1 than in group 2 (P = 0.001). Left ventricular mass index relative to sex specific normal values was increased by 18% in group 1 and by 41% in group 2 (P = 0.04). Cumulative survival rates were slightly although not significantly higher in group 1 than in group 2. Event-free survival was significantly higher in group 1 than in group 2 (P < 0.05). CONCLUSIONS--(1) The development of left ventricular chamber dilatation and systolic dysfunction in hypertrophic cardiomyopathy occurs in approximately 1.5% of the patients per year. (2) Factors associated with left ventricular dilatation are dyspnoea, syncope, a higher functional classification, and a higher degree of left ventricular hypertrophy. (3) Patients with chamber dilatation have a worse prognosis than those without, particularly regarding quality of life.


PLOS ONE | 2011

Clinical outcome of high-risk patients with severe aortic stenosis and reduced left ventricular ejection fraction undergoing medical treatment or TAVI

Thomas Pilgrim; Peter Wenaweser; Fabienne Meuli; Christoph Huber; Stefan Stortecky; C Seiler; Stephan Zbinden; Bernhard Meier; Thierry Carrel; Stephan Windecker

Introduction Reduced left ventricular function in patients with severe symptomatic valvular aortic stenosis is associated with impaired clinical outcome in patients undergoing surgical aortic valve replacement (SAVR). Transcatheter Aortic Valve Implantation (TAVI) has been shown non-inferior to SAVR in high-risk patients with respect to mortality and may result in faster left ventricular recovery. Methods We investigated clinical outcomes of high-risk patients with severe aortic stenosis undergoing medical treatment (nu200a=u200a71) or TAVI (nu200a=u200a256) stratified by left ventricular ejection fraction (LVEF) in a prospective single center registry. Results Twenty-five patients (35%) among the medical cohort were found to have an LVEF≤30% (mean 26.7±4.1%) and 37 patients (14%) among the TAVI patients (mean 25.2±4.4%). Estimated peri-interventional risk as assessed by logistic EuroSCORE was significantly higher in patients with severely impaired LVEF as compared to patients with LVEF>30% (medical/TAVI 38.5±13.8%/40.6±16.4% versus medical/TAVI 22.5±10.8%/22.1±12.8%, p <0.001). In patients undergoing TAVI, there was no significant difference in the combined endpoint of death, myocardial infarction, major stroke, life-threatening bleeding, major access-site complications, valvular re-intervention, or renal failure at 30 days between the two groups (21.0% versus 27.0%, pu200a=u200a0.40). After TAVI, patients with LVEF≤30% experienced a rapid improvement in LVEF (from 25±4% to 34±10% at discharge, pu200a=u200a0.002) associated with improved NYHA functional class at 30 days (decrease ≥1 NYHA class in 95%). During long-term follow-up no difference in survival was observed in patients undergoing TAVI irrespective of baseline LVEF (pu200a=u200a0.29), whereas there was a significantly higher mortality in medically treated patients with severely reduced LVEF (log rank pu200a=u200a0.001). Conclusion TAVI in patients with severely reduced left ventricular function may be performed safely and is associated with rapid recovery of systolic left ventricular function and heart failure symptoms.


American Heart Journal | 2010

Iatrogenic left main coronary artery dissection: Incidence, classification, management, and long-term follow-up

Parham Eshtehardi; Patrick Adorjan; Mario Togni; Hendrick Tevaearai; Rolf Vogel; C Seiler; Bernhard Meier; Stephan Windecker; Thierry Carrel; Peter Wenaweser; Stéphane Cook

BACKGROUNDnAlthough rare, iatrogenic left main coronary artery (LM) dissection is a feared complication of coronary catheterization. Its incidence, optimal therapeutic management, and prognosis remain largely unknown. The aim of the present study was to estimate the incidence, characterize the population at risk, depict the initial management, and evaluate the long-term prognosis of iatrogenic LM dissection.nnnMETHODSnThirty-eight patients who fulfilled the National Heart, Lung, and Blood Institute diagnostic criteria for iatrogenic LM dissection were retrieved from our database and followed up by telephone or physician visit. The primary end point was freedom from major adverse cardiac events (MACE) at 5 years.nnnRESULTSnThe overall incidence of iatrogenic LM dissection during the study period was 0.07% (38/51,452 patients) and almost twice as common with percutaneous coronary intervention than coronary angiography. From 38 patients, 1 (3%) patient died before any therapeutic attempt was performed, 6 (16%) patients were treated conservatively, and 31 (82%) patients underwent stent implantation and/or coronary artery bypass grafting (CABG). In-hospital outcome was favorable irrespective of the therapeutic strategy. During the 5-year follow-up, among 31 patients who underwent revascularization treatment by stenting or CABG, one patient died in each group from a cardiac cause, and MACE were observed in 12 patients (39%). Kaplan-Meier cumulative survival estimates showed no significant difference between different revascularization treatment strategies.nnnCONCLUSIONSnIatrogenic LM dissection is a rare complication of cardiac catheterization procedures with favorable early and long-term outcome when recognized timely and managed properly.

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Bernhard Meier

University Hospital of Bern

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