A Parametric Empirical Bayes Approach to Personalized Reference Intervals and Reference Change Values.

Background: Population-wide reference intervals (RIpop) are commonly used in laboratory medicine but may not reflect an individual's tightly regulated homeostatic interval. Personalized reference intervals (RIper) could enhance diagnostic precision by accounting for individual variability. A parametric empirical Bayes (PEB) framework stabilizes individual estimates using population parameters, enabling reliable RIper even from a limited number of individual results.

Cardiac Troponin: Fragments of the Future?

Cardiac troponin is the gold standard biomarker for the diagnosis of acute myocardial infarction (AMI). Development of high-sensitivity troponin platforms has revolutionized triage of chest pain patients, but specificity for type 1 AMI remains a clinical limitation. Consequently, differentiating type 1 AMI from other forms of myocardial injury is a common conundrum, heightened by the risks associated invasive coronary angiography.

Hemodynamic Valve Deterioration After Transcatheter Aortic Valve Replacement: Incidence, Predictors, and Clinical Outcomes.

Background: Reports on the durability of transcatheter aortic valve replacement (TAVR) prostheses are scarce and confounded by varying definitions and competing risks of death.

Objectives: The authors sought to determine the incidence, predictors, and clinical outcomes of hemodynamic valve deterioration (HVD) according to the Valve Academic Research Consortium 3 definition after TAVR.

Methods: We analyzed consecutive patients undergoing TAVR in the prospective Bern TAVI (Transcatheter Aortic Valve Implantation) registry between August 2007 and June 2022 for the incidence and predictors of HVD and performed case control-matching to compare outcomes according to HVD.

Estimating Reference Change Values Using Routine Patient Data: A Novel Pathology Database Approach.

Background: The reference change value (RCV) is calculated by combining the within-subject biological variation (CVI) and local analytical variation (CVA). These calculations do not account for the variation seen in preanalytical conditions in routine practice or CVI in patients presenting for treatment. As a result, the RCVs may not reflect routine practice or align with clinicians' experiences.

Comparison of troponin and natriuretic peptides in Takotsubo syndrome and acute coronary syndrome: a meta-analysis.

Objective: Takotsubo syndrome (TTS) is an acute heart failure syndrome which resembles acute coronary syndrome (ACS) at presentation. Differentiation requires coronary angiography, but where this does not occur immediately, cardiac biomarkers may provide additional utility. We performed a meta-analysis to compare troponin and natriuretic peptides (NPs) in TTS and ACS to determine if differences in biomarker profile can aid diagnosis.

Non-Vitamin K Antagonist Versus Vitamin K Antagonist Oral Anticoagulant Agents After Transcatheter Aortic Valve Replacement.

Background: Studies comparing long-term outcomes between non-vitamin K antagonist (VKA) oral anticoagulant agents (direct oral anticoagulant agents [DOACs]) and VKA anticoagulant agents after transcatheter aortic valve replacement (TAVR) are scarce, with conflicting results.

Objectives: The aim of this study was to examine the periprocedural, short-term, and long-term safety and effectiveness of DOACs vs VKAs in patients undergoing TAVR via femoral access with concomitant indications for oral anticoagulation.

Methods: Consecutive patients undergoing transfemoral TAVR in the prospective national SwissTAVI Registry between February 2011 and June 2021 were analyzed.

Prognostic impact of cardiac damage staging classification in each aortic stenosis subtype undergoing TAVI.

Background: The prognostic value of cardiac damage staging classifications across the haemodynamic spectrum of severe aortic stenosis (AS) remains unknown.

Aims: We aimed to investigate the prognostic impact of cardiac damage staging classifications in patients with high-gradient AS (HG-AS) and low-gradient AS (LG-AS) undergoing transcatheter aortic valve implantation (TAVI).

Methods: In a prospective TAVI registry, five-year mortality was evaluated for early stages of cardiac damage (stage 0, 1, or 2) and advanced stages of cardiac damage (stage 3 or 4) in patients with HG-AS, classical low-flow (LF) LG-AS, LF LG-AS with preserved ejection fraction (pEF), and normal-flow (NF) LG-AS.

Combined Significant Aortic Stenosis and Mitral Regurgitation: Challenges in Timing and Type of Intervention.

In this narrative review, we aim to summarize the literature surrounding the assessment and management of the common, yet understudied combination of aortic stenosis (AS) and mitral regurgitation (MR), the components of which are complexly inter-related and interdependent from diagnostic, prognostic, and therapeutic perspectives. The hemodynamic interdependency of AS and MR confounds the assessment of the severity of each valve disease, thus underscoring the importance of a multimodal approach integrating valvular and extravalvular indicators of severity. A large body of literature suggests that baseline MR is associated with reduced survival post aortic valve (AV) intervention and that regression of MR post-AV intervention confers a mortality benefit.

Hemodialysis and biomarkers of myocardial infarction - a cohort study.

Objectives: End-stage renal disease is associated with a high risk of cardiovascular disease. We compared the concentration and prognostic ability of high sensitivity cardiac troponin T (hs-cTnT) and I (hs-cTnI) and cardiac myosin-binding protein C (cMyC) among stable hemodialysis patients.

Methods: Patients were sampled before and after hemodialysis.

Impact of COVID-19 Surge Periods on Clinical Outcomes of Transcatheter Aortic Valve Implantation.

Healthcare systems adopted various strategies to minimize the impact of the COVID-19 pandemic on clinical outcomes of patients with symptomatic severe aortic stenosis referred for transcatheter aortic valve implantation (TAVI). We aimed to compare baseline characteristics and procedural and clinical outcomes of patients who underwent TAVI during COVID-19 surge periods with those of patients who underwent TAVI during the nonsurge and prepandemic periods. In the prospective Bern TAVI registry, the pandemic period was divided into surge and nonsurge periods on the basis of the mean number of occupied beds in the intensive care unit in each month and matched with 11 months immediately preceding the pandemic.

Systematic coronary physiology improves level of agreement in diagnostic coronary angiography.

Objective: The training of interventional cardiologists (ICs), non-interventional cardiologists (NICs) and cardiac surgeons (CSs) differs, and this may be reflected in their interpretation of invasive coronary angiography (ICA) and management plan. Availability of systematic coronary physiology might result in more homogeneous interpretation and management strategy compared with ICA alone.

Methods: 150 coronary angiograms from patients with stable chest pain were presented independently to three NICs, three ICs and three CSs.

Sex Hormones and Adrenal Steroids: Biological Variation Estimated Using Direct and Indirect Methods.

Background: Biological variation (BV) data may be used to develop analytical performance specifications (APS), reference change values (RCV), and support the applicability of population reference intervals. This study estimates within-subject BV (CVI) for several endocrine biomarkers using 3 different methodological approaches.

Methods: For the direct method, 30 healthy volunteers were sampled weekly for 10 consecutive weeks.

High incidence of discrepancies in new Siemens assay - a comparison of cardiac troponin I assays.

Objectives: Cardiac troponin (cTn) is the biochemical gold standard for diagnosing myocardial infarction (MI). We compared the Siemens ADVIA Centaur High-Sensitivity (hs-cTnI) assay with the Siemens Ultra assay (cTnI-U).

Methods: Over 3 months cTnI-U and hs-cTnI were measured simultaneously at Herlev-Gentofte Hospital.

A 0/1h-algorithm using cardiac myosin-binding protein C for early diagnosis of myocardial infarction.

Aims: Cardiac myosin-binding protein C (cMyC) demonstrated high diagnostic accuracy for the early detection of non-ST-elevation myocardial infarction (NSTEMI). Its dynamic release kinetics may enable a 0/1h-decision algorithm that is even more effective than the ESC hs-cTnT/I 0/1 h rule-in/rule-out algorithm.

Methods And Results: In a prospective international diagnostic study enrolling patients presenting with suspected NSTEMI to the emergency department, cMyC was measured at presentation and after 1 h in a blinded fashion.

Biological variation of secretoneurin; a novel cardiovascular biomarker implicated in arrhythmogenesis.

Background: Secretoneurin is a novel prognostic biomarker that may predict mortality in heart failure and the occurrence of ventricular arrhythmias. This study reports the within subject variation (CV), between subject variation (CV), reference change values (RCV) and index of individuality (II) of secretoneurin.

Methods: Thirty healthy volunteers were included.

Biological variation of cardiac myosin-binding protein C in healthy individuals.

Objectives: Cardiac myosin-binding protein C (cMyC) is a novel biomarker of myocardial injury, with a promising role in the triage and risk stratification of patients presenting with acute cardiac disease. In this study, we assess the weekly biological variation of cMyC, to examine its potential in monitoring chronic myocardial injury, and to suggest analytical quality specification for routine use of the test in clinical practice.

Methods: Thirty healthy volunteers were included.

Impact and Determinants of High-Sensitivity Cardiac Troponin-T Concentration in Patients With COVID-19 Admitted to Critical Care.

Cardiac Troponin (hs-TnT) elevation has been reported in unselected patients hospitalized with COVID-19 however the mechanism and relationship with mortality remain unclear. Consecutive patients admitted to a high-volume intensive care unit (ICU) in London with severe COVID-19 pneumonitis were included if hs-TnT concentration at admission was known. Kaplan-Meier survival analysis performed, with cohorts classified a priori by multiples of the upper limit of normal (ULN).

Outcome of left main stem percutaneous coronary intervention in a UK nonsurgical center: A 5-year clinical experience.

Objectives: To evaluate the outcome of unprotected left main stem (LMS) percutaneous coronary intervention (PCI) in a large UK nonsurgical center.

Background: PCI on unprotected LMS is increasingly regarded as a viable alternative to coronary artery bypass grafting (CABG) with comparable outcome and safety profile in select groups. The safety and efficacy of unprotected LMS PCI without on-site surgical back up has not been reported.