A qualitative study of the experiences and perceptions of older patients and relatives prior to cardiac surgery.

BACKGROUND: Shared decision-making plays an important role in ensuring value-based healthcare in cardiac surgery. However, the personal situations of patients in cardiac care have not been widely explored, and thus, little is known about the decision-making experiences of patients and their relatives before surgery. OBJECTIVE: To explore the perceptions of patients indicated for cardiac surgery and their relatives during the decision-making process, as well as their experiences of a conversation aimed at achieving shared decision-making in the treatment trajectory. METHODS: The data were collected through semi-structured in-depth interviews with patients aged ≥70 years who were indicated for cardiac surgery and their relatives until theme saturation. Both inductive and deductive analysis were conducted based on the principles of reflexive thematic analysis. RESULTS: Interviews with 16 patients and 10 relatives provided in-depth insights into the experiences of patients and their relatives in terms of a shared decision-making process prior to surgery. Overall, 15 subthemes were identified, and these were divided into three themes. In general, the patients' experiences and perceptions were influenced by their (1) general daily functioning. The relatives were more concerned about (2) social expectations and (3) existential uncertainty. CONCLUSIONS: Patients eligible for cardiac surgery and their families have unique experiences and perceptions during the process of shared decision-making. The subthemes emerging from this study, such as the overestimation of potential medical outcomes by patients and their relatives, who experience fear about the current health situation of their loved one, require careful attention from healthcare professionals during decision-making conversations.

Roles and competencies of nurses and physicians in shared decision-making in cardiac surgery: A scoping review.

AIM: Identification and synthesis of research data related to the roles and competencies of physicians and nurses that are prerequisites for careful shared decision-making with patients potentially undergoing cardiac surgery. DESIGN: A scoping review was conducted in accordance with the Joanna Briggs Institute's methodology for scoping reviews and the PRISMA Extension for Scoping Reviews. METHODS: PubMed, EMBASE and CINAHL were searched from inception dates up to March 2022, to identify primary studies published in a peer-reviewed journal. Study selection, assessment of the methodological quality and data extracting of the included studies were done by at least two independent researchers. To describe the findings of the studies, an emergent synthesis approach was used to visualize a descriptive representation of professional roles and competencies in shared decision-making, in an overview. RESULTS: The systematic search revealed 10,055 potential papers, 8873 articles were screened on title and abstract and 76 full texts were retrieved. Eight articles were included for final evaluation. For nurses and physicians, 26 different skills were identified in the literature to practice shared decision-making in cardiac surgery. The skills that emerged were divided into five professional roles: moderator; health educator; data collector; psychological supporter and translator. CONCLUSIONS: This review specifies the professional roles and required competencies related to shared decision-making in cardiac surgery. Further research is needed to compare our findings with other clinical areas and from there to arrive at a professional division of roles between the different clinical disciplines involved. IMPACT: The visualization of generic shared decision-making competencies and roles should establish the professional division of positions between various clinical physician and nurse disciplines in order to create a treatment plan based on evidence, values, preferences and the patient's personal situation. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Multicentre experience with valve-sparing aortic root replacement by means of combined remodelling and external aortic ring annuloplasty in patients with Marfan syndrome.

OBJECTIVES: The most recent valve-sparing root replacement technique combines the advantages of the reimplantation (David) and remodelling (Yacoub) techniques. The aortic root is reconstructed according to the remodelling technique, the aortic valve is repaired according to the principle of effective height, and an external ring provides annular support. The purpose of this study was to evaluate operative and mid-term outcomes using this technique in patients with Marfan syndrome. METHODS: Adult patients with Marfan syndrome who had an indication for aortic root surgery according to European Society of Cardiology guidelines and were operated on using this new root replacement technique were retrospectively evaluated. Follow-up was obtained from standard outpatient visits and included echocardiography. RESULTS: The study group comprised 22 patients (mean age 36 years, 68% males). Mean follow-up was 7.5 years. There were no mortalities. Two patients required aortic valve replacement because of aortic regurgitation. In both patients, the aortic root was severely dilated (≥65 mm) preoperatively, with grade III aortic valve regurgitation and aortic valve cusps that were very fragile. Aortic regurgitation was grade ≤I on follow-up in 18 of the remaining 20 patients. CONCLUSIONS: Valve-sparing root replacement using remodelling combined with aortic-ring annuloplasty is safe in patients with Marfan syndrome. The mid-term outcome is promising in patients undergoing elective valve-sparing root replacement at recommended root diameters. However, in patients with extremely dilated aortic roots and already severe aortic regurgitation, the technique should be used cautiously as aortic cusps are fragile and might not be suitable for durable repair. CLINICAL REGISTRATION NUMBER: UMCG Research registry #11208.

Feasibility of preoperative and postoperative physical rehabilitation for cardiac surgery patients - a longitudinal cohort study.

BACKGROUND: This study aimed to determine the feasibility of a preoperative and postoperative (in- and outpatient) physical rehabilitation program, the Heart-ROCQ-pilot program. METHODS: This cohort study included patients undergoing cardiac surgery (including coronary artery bypass graft surgery, valve surgery, aortic surgery, or combinations of these surgeries) and participated in the Heart-ROCQ-pilot program. Feasibility involved compliance and characteristics of bicycle and strength training sessions in the three rehabilitation phases. RESULTS: Of the eligible patients, 56% (n = 74) participated in the program (41% of exclusions were due to various health reasons). On average across the rehabilitation phases, the compliance rates of bicycle and strength training were 88% and 83%, respectively. Workload to heart rate (W/HR) ratio and total absolute volume load for bicycle and strength training, respectively, improved in each rehabilitation phase (P < 0.05). The W/HR-ratio was higher during the last postoperative session compared to the first preoperative session (0.48 to 0.63 W/beat, P < 0.001) and similar to the last preoperative session (0.65 to 0.64 W/beat, P < 0.497). During less than 1% of the bicycle sessions, patients reported discomfort scores of 5 to 6 (scale 0-10, with higher scores indicating a higher level). CONCLUSIONS: The Heart-ROCQ-pilot program was feasible for patients awaiting cardiac surgery. Patients were very compliant and were able to safely increase the training load before surgery and regained this improvement within eight weeks after surgery.

Long-Term Performance of Epicardial versus Transvenous Left Ventricular Leads for Cardiac Resynchronization Therapy.

Aims: to study the technical performance of epicardial left ventricular (LV) leads placed via video assisted thoracic surgery (VATS), compared to transvenously placed leads for cardiac resynchronization therapy (CRT). Methods: From 2001 until 2013, a total of 644 lead placement procedures were performed for CRT. In the case of unsuccessful transvenous LV lead placement, the patient received an epicardial LV lead. Study groups consist of 578 patients with a transvenous LV lead and 66 with an epicardial LV lead. The primary endpoint was LV-lead failure necessitating a replacement or deactivation. The secondary endpoint was energy consumption. Results: The mean follow up was 5.9 years (epicardial: 5.5 ± 3.1, transvenous: 5.9 ± 3.5). Transvenous leads failed significantly more frequently than epicardial leads with a total of 66 (11%) in the transvenous leads group vs. 2 (3%) in the epicardial lead group (p = 0.037). Lead energy consumption was not significantly different between groups. Conclusions: Epicardial lead placement is feasible, safe and shows excellent long-term performance compared to transvenous leads. Epicardial lead placement should be considered when primary transvenous lead placement fails or as a primary lead placement strategy in challenging cases.

Muscle strength trajectories and their association with postoperative health-related quality of life in patients undergoing coronary artery bypass grafting surgery: a prospective cohort study.

BACKGROUND: Patients with sarcopenia have a higher risk of poor recovery after coronary artery bypass grafting (CABG). Little is known about the impact of changes in muscle strength (the primary indicator for sarcopenia) on health-related quality of life (HR-QoL). This study aimed to (1) identify subgroups with different muscle strength trajectories, (2) identify differences in preoperative risk factors among trajectory group membership, and (3) explore their prognostic value on postoperative HR-QoL in patients undergoing CABG. METHODS: In this prospective observational study 131 patients undergoing elective CABG completed grip strength tests and HR-QoL questionnaires. Latent Class Growth Mixture Modelling (LCGMM) was used to identify clinically relevant trajectories (> 5% of study population) for weight-normalised grip strength, measured at admission, 3 days, and 6 months after surgery. Differences between trajectory group membership at baseline were evaluated. The impact of trajectory group membership on postoperative HR-QoL was evaluated with multiple linear regression models. RESULTS: Due to low numbers (n = 15), female patients were excluded from LCGMM and subsequent statistical analyses. In males (n = 116), we identified two main weight-normalised grip strength trajectories: a "stable average" trajectory with a slight decline immediately post-surgery and recovery to preoperative levels (n = 85) and a "high" trajectory with a considerable immediate decline after surgery but followed towards a higher level of recovery compared to preoperative level (n = 27). The "stable average" patients were older (68 vs. 57 years; P = 0.003), had more diabetes (27% vs. 4%; P = 0.01) and had a higher BMI (27.8 vs. 24.8; P = 0.005) compared to the "high" group. After correction for age, diabetes, and baseline HR-QoL, group trajectory membership was not associated with postoperative HR-QoL, yet an increase in individual change scores of weight-normalised grip strength was associated with a better postoperative HR-QoL. We also identified one small trajectory group (n = 4, ≤ 5%). CONCLUSIONS: This study showed two relevant weight-normalised grip strength trajectories in male patients undergoing CABG, varying in important preoperative risk factors. While change scores of grip strength per weight did predict postoperative HR-QoL, the trajectory subgroups could not predict postoperative HR-QoL. Future research should focus on female patients, reacting potentially different on CABG and/or rehabilitation treatment. Trial registration NCT03774342, 12-12-2018.

Clinical monitoring of activated clotting time during cardiothoracic surgery: comparing the Hemochron® Response and Hemochron® Signature Elite.

INTRODUCTION: The Activated Clotting Time (ACT) is commonly used to manage anticoagulation during cardiac surgery. The aim of this study was to compare the older manually operated Hemochron® Response and the automated Hemochron® Signature Elite. METHODS: In this observational study the clinically relevant differences of both devices were investigated simultaneously, using duplicate measurements, in 29 patients who underwent a Coronary Artery Bypass Grafting (CABG) or Aortic Valve Replacement (AVR) in order to determine reliability, bias, and to detect which method has the lowest variation. Blood samples were obtained from the arterial line prior to surgery, after administration of 300 IU/kg heparin, 5 minutes after initiation of cardiopulmonary bypass and successively every 30 minutes, and after protamine administration. RESULTS: A total of 202 measurements were performed. Of these 10 measurements were out of range in the Response and 9 in the Elite. About 27 single unstable magnet errors were seen in the Response versus no measurement errors in the Elite. No statistically significant differences between the Response (p = 0.22, Wilcoxon rank) and Elite (p = 0.064) duplicates were observed. The Response values were consistently higher during heparinization than the Elite measurements (p = 0.002, repeated measurements) with an average positive bias of around 56 seconds during heparinization (Bland-Altman). Overall, the coefficient of variation (CoV) increased during heparinization. CONCLUSION: The Elite was more reliable, but the variation was higher for the Elite than the Response. The observed positive bias in the Response compared to the Elite could affect heparin administration during surgery making the two systems not interchangeable.

Mitral Valve Coaptation Reserve Index: A Model to Localize Individual Resistance to Mitral Regurgitation Caused by Annular Dilation.

OBJECTIVES: The objective of this study was to develop a mathematical model for mitral annular dilatation simulation and determine its effects on the individualized mitral valve (MV) coaptation reserve index (CRI). DESIGN: A retrospective analysis of intraoperative transesophageal 3-dimensionalechocardiographic MV datasets was performed. A mathematical model was created to assess the mitral CRI for each leaflet segment (A1-P1, A2-P2, A3-P3). Mitral CRI was defined as the ratio between the coaptation reserve (measured coaptation length along the closure line) and an individualized correction factor. Indexing was chosen to correct for MV sphericity and area of largest valve opening. Mathematical models were created to simulate progressive mitral annular dilatation and to predict the effect on the individual mitral CRI. SETTING: At a single-center academic hospital. PARTICIPANTS: Twenty-five patients with normally functioning MVs undergoing cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Direct measurement of leaflet coaptation along the closure line showed the lowest amount of coaptation (reserve) near the commissures (A1-P1 0.21 ± 0.05 cm and A3-P3 0.22 ± 0.06 cm), and the highest amount of coaptation (reserve) at region A2 to P2 0.25 ± 0.06 cm. After indexing, the A2-to-P2 region was the area with the lowest CRI in the majority of patients, and also the area with the least resistance to mitral regurgitation (MR) occurrence after simulation of progressive annular dilation. CONCLUSIONS: Quantification and indexing of mitral coaptation reserve along the closure line are feasible. Indexing and mathematical simulation of progressive annular dilatation consistently showed that indexed coaptation reserve was lowest in the A2-to-P2 region. These results may explain why this area is prone to lose coaptation and is often affected in MR.

Staged single-port thoracoscopic R2 sympathicotomy as a reproducible, safe and effective treatment option for debilitating severe facial blushing.

OBJECTIVES: Our goal was to investigate the safety, feasibility, success rate, complication rate and side effects of staged single-port thoracoscopic R2 sympathicotomy in the treatment of severe facial blushing. Facial blushing is considered a benign condition; however, severe facial blushing can have a major impact on quality of life. When nonsurgical options such as medication and psychological treatments offer no or insufficient relief, surgical treatment with thoracoscopic sympathicotomy should be considered. METHODS: All patients who underwent a staged thoracoscopic sympathicotomy at level R2 for severe facial blushing between January 2016 and September 2021 were included. Clinical and surgical data were prospectively collected and analysed. RESULTS: A total of 16 patients with low operative risk (American Society of Anesthesiologists class 1) were treated. No major perioperative complications were encountered. One patient experienced postoperative unilateral Horner's syndrome that resolved completely after 1 week. Two patients experienced compensatory hyperhidrosis. The success rate was 100%. One patient experienced a slight recurrence of blushing symptoms after 3 years that did not interfere with their quality of life. All patients were satisfied with the results and had no regrets of having undergone the procedure. CONCLUSIONS: Staged single-port thoracoscopic R2 sympathicotomy is a reproducible, safe and highly effective surgical treatment option with low compensatory hyperhidrosis rates and the potential to significantly improve quality of life in carefully selected patients suffering from severe facial blushing. We would like to increase awareness among healthcare professionals for debilitating facial blushing and suggest timely referral for surgical treatment.

Comparison of Machine Learning Models Including Preoperative, Intraoperative, and Postoperative Data and Mortality After Cardiac Surgery.

Importance: A variety of perioperative risk factors are associated with postoperative mortality risk. However, the relative contribution of routinely collected intraoperative clinical parameters to short-term and long-term mortality remains understudied. Objective: To examine the performance of multiple machine learning models with data from different perioperative periods to predict 30-day, 1-year, and 5-year mortality and investigate factors that contribute to these predictions. Design, Setting, and Participants: In this prognostic study using prospectively collected data, risk prediction models were developed for short-term and long-term mortality after cardiac surgery. Included participants were adult patients undergoing a first-time valve operation, coronary artery bypass grafting, or a combination of both between 1997 and 2017 in a single center, the University Medical Centre Groningen in the Netherlands. Mortality data were obtained in November 2017. Data analysis took place between February 2020 and August 2021. Exposure: Cardiac surgery. Main Outcomes and Measures: Postoperative mortality rates at 30 days, 1 year, and 5 years were the primary outcomes. The area under the receiver operating characteristic curve (AUROC) was used to assess discrimination. The contribution of all preoperative, intraoperative hemodynamic and temperature, and postoperative factors to mortality was investigated using Shapley additive explanations (SHAP) values. Results: Data from 9415 patients who underwent cardiac surgery (median [IQR] age, 68 [60-74] years; 2554 [27.1%] women) were included. Overall mortality rates at 30 days, 1 year, and 5 years were 268 patients (2.8%), 420 patients (4.5%), and 612 patients (6.5%), respectively. Models including preoperative, intraoperative, and postoperative data achieved AUROC values of 0.82 (95% CI, 0.78-0.86), 0.81 (95% CI, 0.77-0.85), and 0.80 (95% CI, 0.75-0.84) for 30-day, 1-year, and 5-year mortality, respectively. Models including only postoperative data performed similarly (30 days: 0.78 [95% CI, 0.73-0.82]; 1 year: 0.79 [95% CI, 0.74-0.83]; 5 years: 0.77 [95% CI, 0.73-0.82]). However, models based on all perioperative data provided less clinically usable predictions, with lower detection rates; for example, postoperative models identified a high-risk group with a 2.8-fold increase in risk for 5-year mortality (4.1 [95% CI, 3.3-5.1]) vs an increase of 11.3 (95% CI, 6.8-18.7) for the high-risk group identified by the full perioperative model. Postoperative markers associated with metabolic dysfunction and decreased kidney function were the main factors contributing to mortality risk. Conclusions and Relevance: This study found that the addition of continuous intraoperative hemodynamic and temperature data to postoperative data was not associated with improved machine learning-based identification of patients at increased risk of short-term and long-term mortality after cardiac operations.

Treatment of resistant Raynaud's phenomenon with single-port thoracoscopic sympathicotomy: One-year follow-up.

OBJECTIVE: Follow-up of patients with treatment-resistant Raynaud's phenomenon (RP) one-year after single-port thoracoscopic sympathicotomy (SPTS). METHODS: Eight patients (six males, two females, median age of 45 years) with treatment-resistant RP underwent left-sided SPTS at the third rib (R3), unilaterally. Questionnaires were taken, and number and duration of RP attacks were reported over a 2-week period. Perfusion was assessed with a cooling and recovery procedure at baseline and one year after SPTS. Furthermore, laser speckle contrast analysis, pulse wave velocity, heart rate variability and nailfold capillary microscopy were performed. RESULTS: One year after SPTS the duration of the attacks of was reduced with 1.9 h in the left hand versus 0.3 h in the right hand. Furthermore, three aspects of the questionnaire showed a significant improvement (role limitations due to physical health (p = 0.017), pain (p = 0.027) and physical functioning (p = 0.025)). The total area under the curve of the total cooling and recovery procedure of the left hand was larger one year after surgery (101 (75-140) at baseline versus 118 (95-190) one year post-operatively, p = 0.012), implying a better perfusion in the fingers. This was mainly due to the improvement during the recovery phase (21 (1-41) at baseline versus 38 (24-43) one year post-operatively, p = 0.028). CONCLUSION: One year after unilateral R3 SPTS the benefit with regard to the majority of outcome variables persisted, though some effects seem to attenuate. Long-term effects and long-term follow-up results will be investigated in an on-going study. CLINICAL TRIAL REGISTRATION NUMBER: NCT02680509.

Contained rupture of a sinus of Valsalva aneurysm: Is it just a matter of luck?

BACKGROUND: Contained rupture of the ascending aorta is a rare condition, but the severity of this complication enforces strict guidelines for its prevention and a prompt diagnosis, once already occurred. CASE PRESENTATION: A 66-year-old man with a history of type 2 diabetes, longstanding aortic valve stenosis and aortic root aneurysm of 47 mm was hospital admitted for elective surgery. A Bentall-De Bono procedure was performed in order to replace the stenotic bicuspid aortic valve and exclude the dilated portion of the aortic wall. Intraoperatively, a discontinuity of the aortic wall, just above the aortic annulus, at the non-coronary sinus of Valsalva was incidentally observed. The aortic wall discontinuity was none other than a contained aortic rupture. The preoperative CT-scan images were afterwards analyzed by the radiologist, in order to identify the contained aortic rupture. Indeed a false aneurysm of the non-coronary sinus of Valsalva of a maximum diameter of 15 mm was detected, thanks to a 3D reconstruction. CONCLUSIONS: The diagnosis of contained aortic rupture is certainly demanding, particularly in absence of signs or symptoms of rupture in a chamber of the heart or in the pericardium. Although this case represents a consensus of experts' opinion, the recognition of these specific cases in which the risk of dissection, rupture or death is at its highest, would allow to operate at the appropriate time, improving the outcomes.

Minimally Invasive Sympathicotomy for Palmar Hyperhidrosis and Facial Blushing: Current Status and the Hyperhidrosis Expert Center Approach.

Hyperhidrosis, the medical term for excessive sweating beyond physiological need, is a condition with serious emotional and social consequences for affected patients. Symptoms usually appear in focal areas such as the feet, hands, axillae and face. Non-surgical treatment options such as topical antiperspirants or systemic medications are usually offered as a first step of treatment, although these therapies are often ineffective, especially in severe and intolerable cases of hyperhidrosis. In the treatment algorithm for patients suffering from hyperhidrosis, surgical thoracoscopic sympathicotomy offers a permanent solution, which is particularly effective in the treatment of palmar hyperhidrosis and facial blushing. In this review, we describe the current status of thoracoscopic sympathicotomy for palmar hyperhidrosis and facial blushing. In addition, we share the specific treatment approach, technique and results of our Hyperhidrosis Expert Center. Last, we share recommendations to ensure an effective, reproducible and safe application of single-port thoracoscopic sympathicotomy for palmar hyperhidrosis and facial blushing, based on our extensive experience.

Oxygenated machine perfusion at room temperature as an alternative for static cold storage in porcine donor hearts.

BACKGROUND: There is a continued interest in ex situ heart perfusion as an alternative strategy for donor heart preservation. We hypothesize that oxygenated machine perfusion of donor hearts at a temperature that avoids both normothermia and deep hypothermia offers adequate and safe preservation. METHODS: Cardioplegia-arrested porcine donor hearts were randomly assigned to six hours of preservation using cold storage (CS, n = 5) or machine perfusion using an oxygenated acellular perfusate at 21°C (MP, n = 5). Subsequently, all grafts were evaluated using the Langendorff method for 120 min. Metabolic parameters and histology were analyzed. Systolic function was assessed by contractility and elastance. Diastolic function was assessed by lusitropy and stiffness. RESULTS: For both groups, in vivo baseline and post-Langendorff biopsies were comparable, as were lactate difference and myocardial oxygen consumption. Injury markers gradually increased and were comparable. Significant weight gain was seen in MP (p = 0.008). Diastolic function was not impaired in MP, and lusitropy was superior from 30 min up to 90 min of reperfusion. Contractility was superior in MP during the first hour of evaluation. CONCLUSION: We conclude that the initial functional outcome of MP-preserved hearts was transiently superior compared to CS, with no histological injury post-Langendorff. Our machine perfusion strategy could offer feasible and safe storage of hearts prior to transplantation. Future studies are warranted for further optimization.

Comparison of renal region, cerebral and peripheral oxygenation for predicting postoperative renal impairment after CABG.

Patients undergoing coronary artery bypass grafting (CABG) are at risk of developing postoperative renal impairment, amongst others caused by renal ischemia and hypoxia. Intra-operative monitoring of renal region tissue oxygenation (SrtO2) might be a useful tool to detect renal hypoxia and predict postoperative renal impairment. Therefore, the aim of this study was to assess the ability of intra-operative SrtO2 to predict postoperative renal impairment, defined as an increase of serum creatinine concentrations of  > 10% from individual baseline, and compare this with the predictive abilities of peripheral and cerebral tissue oxygenation (SptO2 and SctO2, respectively) and renal specific tissue deoxygenation. Forty-one patients undergoing elective CABG were included. Near-infrared spectroscopy (NIRS) was used to measure renal region, peripheral (thenar muscle) and cerebral tissue oxygenation during surgery. Renal region specific tissue deoxygenation was defined as a proportionally larger decrease in SrtO2 than SptO2. ROC analyses were used to compare predictive abilities. We did not observe an association between tissue oxygenation measured in the renal region and cerebral oxygenation and postoperative renal impairment in this small retrospective study. In contrast, SptO2 decrease > 10% from baseline was a reasonable predictor with an AUROC of 0.767 (95%CI 0.619 to 0.14; p = 0.010). Tissue oxygenation of the renal region, although non-invasively and continuously available, cannot be used in adults to predict postoperative renal impairment after CABG. Instead, peripheral tissue deoxygenation was able to predict postoperative renal impairment, suggesting that SptO2 provides a better indication of 'general' tissue oxygenation status.Registered at ClinicalTrials.gov: NCT01347827, first submitted April 27, 2011.

A portable isometric knee extensor strength testing device: test-retest reliability and minimal detectable change scores of the Q-Force ӀӀ in healthy adults.

BACKGROUND: Although knee extensors are essential in daily activities (e.g. walking, climbing stairs), knee extensor strength is often not measured in clinical settings. Existing devices to test muscle strength are not always suitable to accurately measure the high forces of this muscle group. Therefore, a device to test muscle strength that is convenient, feasible, reliable, and valid in clinical settings is required. This study evaluated the reliability, responsiveness, and level of discomfort of the newly developed Q-Force ӀӀ (i.e. a portable device to measure isometric knee extensor strength) in healthy middle-aged and elderly adults. METHODS: Participants (n = 22) conducted two standardized test sessions on the Q-Force ӀӀ (five to ten days apart). Each session consisted of one familiarisation trial followed by three trials of peak isometric knee extension per each leg. Per trial, peak and mean knee extension force (N) and torque (Nm) were measured at 90° flexion. The level of discomfort was determined using a visual analog scale (VAS: 0-100). Intra Class Correlation (ICC, model: two-way mixed with absolute agreement), Standard Error of Measurement (SEM), and minimal detectable change (MDC) were determined. A repeated measures ANOVA was used to determine between-test variation. RESULTS: Excellent test-retest (ICC > 0.95) and inter-trial (ICC > 0.91) reliability for both legs were shown. No significant differences were found in peak and mean knee forces and torques between test and retest of both legs, indicating good test-retest reliability (P-value range: 0.360-0.538; F(1,21) range: 0.4-0.9). The SEM of the peak and mean forces and torques ranged from 28.0 to 30.4 N (6.0-6.8%) and from 9.2 to 10.4 Nm (6.4-7.7%), respectively. The MDC for these outcomes ranged respectively from 77.6 to 84.1 N (16.5-18.8%) and from 25.5 to 28.9 Nm (17.6-21.4%). The level of discomfort was low (median range: 7-10, IQR: 4-18). CONCLUSION: The portable Q-Force ӀӀ is a comfortable, responsive, and relatively cheap device with excellent test-retest reliability. This device would be potentially suitable to measure isometric knee extensor strength in clinical settings.

Left atrial geometry in an ovine ischemic mitral regurgitation model: implications for transcatheter mitral valve replacement devices with a left atrial anchoring mechanism.

BACKGROUND: Transcatheter mitral valve replacement (TMVR) is a challenging, but promising minimally invasive treatment option for patients with mitral valve disease. Depending on the anchoring mechanism, complications such as mitral leaflet or chordal disruption, aortic valve disruption or left ventricular outflow tract obstruction may occur. Supra-annular devices only anchor at the left atrial (LA) level with a low risk of these complications. For development of transcatheter valves based on LA anchoring, animal feasibility studies are required. In this study we sought to describe LA systolic and diastolic geometry in an ovine ischemic mitral regurgitation (IMR) model using magnetic resonance imaging (MRI) and echocardiography in order to facilitate future research focusing on TMVR device development for (I)MR with LA anchoring mechanisms. METHODS: A group of 10 adult male Dorsett sheep underwent a left lateral thoracotomy. Posterolateral myocardial infarction was created by ligation of the left circumflex coronary artery, the obtuse marginal and diagonal branches. MRI and echocardiography were performed at baseline and 8 weeks after myocardial infarction (MI). RESULTS: Six animals survived to 8 weeks follow-up. All animals had grade 2 + or higher IMR 8 weeks post-MI. All LA geometric parameters did not change significantly 8 weeks post-MI compared to baseline. Diastolic and systolic interpapillary muscle distance increased significantly 8 weeks post-MI. CONCLUSIONS: Systolic and diastolic LA geometry do not change significantly in the presence of grade 2 + or higher IMR 8 weeks post-MI. These findings help facilitate future tailored TMVR device development with LA anchoring mechanisms.