Publications by authors named "Matti Niemela"

Article Synopsis
  • * In a trial with 455 patients, those who received PCI had a lower rate of major adverse cardiac events (26%) compared to those with conservative treatment (36%) at a two-year follow-up.
  • * However, the PCI group experienced a higher rate of bleeding events (28% vs. 20%) and had some minor procedure-related complications, indicating that while PCI may reduce cardiac risks, it also carries potential safety concerns.
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Background And Aims: Transcatheter aortic valve implantation (TAVI) has become the first choice to treat older patients with severe symptomatic aortic stenosis (AS). This study aimed to compare TAVI with surgery in low-risk patients ≤75 years of age, including both tricuspid and bicuspid AS.

Methods: The Nordic Aortic Valve Intervention (NOTION)-2 trial enrolled and 1:1 randomized low-risk patients aged ≤75 years with severe symptomatic AS to TAVI or surgery.

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Objectives: Patients receiving transcatheter aortic valve implantation (TAVI) are elderly with multiple comorbidities and at increased risk of perioperative cerebrovascular events. Retinal vasculature represents a surrogate of central nervous system circulation and is noninvasively achievable by retinal imaging. The aim of this study was to evaluate the applicability of retinal angiography of microvascular complications and association to cerebral ischemic events during TAVI.

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The present study provides a novel, selective analysis method for the determination of low xanthate concentrations. The rising concern over the environmental effects of xanthates demands the development of analysis methods which this study answers. Complex formation in aqueous solution between xanthates and an excess of Co(II), Ni(II), Pb(II), Cd(II), Cu(II), and Zn(II) ions was utilized to selectively determine xanthates by high-performance liquid chromatography-inductively coupled plasma tandem mass spectrometry for the first time.

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Background: Transaxillary (TAx) transcatheter aortic valve implantation (TAVI) is a preferred alternative access in patients ineligible for transfemoral TAVI.

Aims: This study used the Trans-AXillary Intervention (TAXI) registry to compare procedural success according to different types of transcatheter heart valves (THV).

Methods: For the TAXI registry anonymized data of patients treated with TAx-TAVI were collected from 18 centers.

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Background: Patients with severe aortic stenosis and left ventricular systolic dysfunction have a poor prognosis, and this may result in inferior survival also after aortic valve replacement. The outcomes of transcatheter and surgical aortic valve replacement were investigated in this comparative analysis.

Methods: The retrospective nationwide FinnValve registry included data on patients who underwent transcatheter or surgical aortic valve replacement with a bioprosthesis for severe aortic stenosis.

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Background: In patients with some cardiovascular disease conditions, slightly elevated body mass index (BMI) is associated with a lower mortality risk (termed "obesity paradox"). It is uncertain, however, if this obesity paradox exists in patients who have had invasive cardiology procedures. We evaluated the association between BMI and mortality in patients who underwent coronary angiography.

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Background: Coronary artery disease (CAD) frequently coexists with severe aortic valve stenosis (AS) in patients planned for transcatheter aortic valve implantation (TAVI). How to manage CAD in this patient population is still an unresolved question. In particular, it is still not known whether fractional flow reserve (FFR) guided revascularization with percutaneous coronary intervention (PCI) is superior to medical treatment for CAD in terms of clinical outcomes.

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Background: The main aim of the research was to study short-term changes in the concentrations of elements in two widely distributed plant species, couch grass and nettle and in the rhizosphere soil of the plants.

Methods: The sampling of plants and soil was carried out on three dates: 3, 10, and 25 May 2021. On each day of sampling, the plants and soil were collected three times: at 9:00, 14:00, and 19:00.

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The rising concern over the environmental impact of xanthates, especially in the arctic region, has increased the need to study these traditional flotation reagents in greater detail. The environmental concern relates mostly to the formation of carbon disulfide (CS) and the heavy metal complexes of xanthates. Due to the unstable nature and multiple reaction mechanisms of xanthates, their reliable determination at low concentration levels is difficult.

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Recent studies showed the favorable outcomes of transcatheter aortic valve implantation (TAVI) in patients with bicuspid aortic valve (BAV) stenosis. However, data on the relation between BAV morphology and optimal transcatheter heart valve (THV) selection are limited. This study sought to evaluate the determinants of device performance in patients with BAV who underwent TAVI.

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Article Synopsis
  • Transcatheter aortic valve implantation (TAVI) using a percutaneous axillary approach is being evaluated for its safety and effectiveness compared to traditional surgical access.
  • An international study analyzed data from 432 patients, revealing that while the percutaneous approach had a higher rate of primary hemostasis failure, it led to shorter hospital stays and lower risks of major complications.
  • The findings suggest that percutaneous axillary access is as effective or potentially superior to surgical access for TAVI, especially for patients who cannot use the femoral approach.
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Objectives: The authors aimed to investigate the impact of severe bleeding and use of red blood cell (RBC) transfusion on the development of postoperative stroke after surgical (SAVR) and transcatheter aortic valve replacement (TAVR), taken from the FinnValve registry.

Design: Nationwide, retrospective observational study.

Setting: Five Finnish university hospitals participated in the registry.

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Introduction: Implantation depth and membranous septum (MS) length have been established as the predictors of new-onset conduction disturbance (CD) after transcatheter aortic valve replacement (TAVR) for tricuspid aortic valve (TAV) stenosis. However, little is known about the predictors with bicuspid aortic valve (BAV). This study investigated the role of MS length and implantation depth in predicting CD following TAVR with a balloon-expandable valve in patients with BAV.

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Background: Transcatheter aortic valve replacement is an evolving interventional therapy for patients with symptomatic severe aortic stenosis. Infolding (INF) as wrinkling along the valve frame is only seen in self-expandable transcatheter valves or surgical sutureless prostheses and is known to be a very rare event during delivery but probably underreported. Therefore, we aimed to (1) determine the frequency of events, (2) identify potential predictors of INF, and (3) evaluate the potential clinical impact of this adverse event.

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Black porous silicon nanoparticles (BPSi NPs) are known as highly efficient infrared light absorbers that are well-suitable for photothermal therapy (PTT) and photoacoustic imaging (PAI). PTT and PAI require a sufficient number of effectively light-absorbing NPs to be accumulated in tumor after intravenous administration. Herein, biodistribution of PEGylated BPSi NPs with different sizes (i.

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Information about biological significance and possible phytotoxicity of many trace elements is still scarce. Bromine and neodymium are among the poorly investigated trace elements. In the research, greenhouse experiment was conducted to study the effects of bromide of neodymium on wheat seedlings grown in soil and water.

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Objectives: We aimed to determine the safety and efficacy of the Allegra transcatheter heart valve (THV) for the treatment of severe aortic valve stenosis in a large patient population treated under real-world conditions.

Background: The Allegra is a novel self-expanding THV with supra-annular bovine leaflets. The valve is available in three different sizes (23, 27, and 31 mm), all are delivered through an 18F sheath.

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The aim of this study was to investigate the impact of anatomical site status and major vascular complication (MVC) severity on the outcome of transfemoral transcatheter aortic valve replacement (TF-TAVR). The FinnValve registry enrolled consecutive TAVR patients from 2008 to 2017. MVC was divided into 2 groups: non-access site-related MVC (i.

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Background: Women present specific risks for transcatheter aortic valve replacement (TAVI) but there are scarce sex-based analysis. The aim of this study was to explore the risk of vascular/bleeding complications in females vs. males that underwent TAVI and the impact of red blood cell (RBC) transfusion.

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Environmental pollution is becoming one of the most important global problems. Understanding the main factors affecting accumulation of toxic trace elements in consumed crops is of particular value. Unfortunately, possible toxicity of many trace elements is still poorly studied.

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Objectives: To compare the outcomes after surgical (SAVR) and transcatheter aortic valve replacement (TAVR) for severe stenosis of bicuspid aortic valve (BAV).

Methods: We evaluated the early and mid-term outcome of patients with stenotic BAV who underwent SAVR or TAVR for aortic stenosis from the nationwide FinnValve registry.

Results: The FinnValve registry included 6463 AS patients and 1023 (15.

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Objectives: The aim of this study was to evaluate the incidence and prognostic impact of paravalvular regurgitation (PVR) on the outcome after transcatheter (TAVR) and surgical aortic valve replacement (SAVR) for aortic stenosis.

Methods: The nationwide FinnValve registry included data on 6463 consecutive patients who underwent TAVR (n = 2130) or SAVR (n = 4333) with a bioprosthesis for the treatment of aortic stenosis during 2008-2017. The impact of PVR at discharge after TAVR and SAVR on 4-year mortality was herein investigated.

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