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6 result(s) for "Hansen, Jacob Valentin"
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Impact of sternotomy and pericardiotomy on cardiopulmonary haemodynamics in a large animal model
New Findings What is the central question of this study? Invasive cardiovascular instrumentation can occur through closed‐ or open‐chest approaches. To what extent will sternotomy and pericardiotomy affect cardiopulmonary variables? What is the main finding and its importance? Opening of the thorax decreased mean systemic and pulmonary pressures. Left ventricular function improved, but no changes were observed in right ventricular systolic measures. No consensus or recommendation exists regarding instrumentation. Methodological differences risk compromising rigour and reproducibility in preclinical research. Animal models of cardiovascular disease are often evaluated by invasive instrumentation for phenotyping. As no consensus exists, both open‐ and closed‐chest approaches are used, which might compromise rigour and reproducibility in preclinical research. We aimed to quantify the cardiopulmonary changes induced by sternotomy and pericardiotomy in a large animal model. Seven pigs were anaesthetized, mechanically ventilated and evaluated by right heart catheterization and bi‐ventricular pressure–volume loop recordings at baseline and after sternotomy and pericardiotomy. Data were compared by ANOVA or the Friedmann test where appropriate, with post‐hoc analyses to control for multiple comparisons. Sternotomy and pericardiotomy caused reductions in mean systemic (−12 ± 11 mmHg, P = 0.027) and pulmonary pressures (−4 ± 3 mmHg, P = 0.006) and airway pressures. Cardiac output decreased non‐significantly (−1329 ± 1762 ml/min, P = 0.052). Left ventricular afterload decreased, with an increase in ejection fraction (+9 ± 7%, P = 0.027) and coupling. No changes were observed in right ventricular systolic function or arterial blood gases. In conclusion, open‐ versus closed‐chest approaches to invasive cardiovascular phenotyping cause a systematic difference in key haemodynamic variables. Researchers should adopt the most appropriate approach to ensure rigour and reproducibility in preclinical cardiovascular research.
Effects of Mechanical Ventilation Versus Apnea on Bi-Ventricular Pressure-Volume Loop Recording
Respiration changes intrathoracic pressure and lung volumes in a cyclic manner, which affect cardiac function. Invasive ventricular pressure-volume (PV) loops can be recorded during ongoing mechanical ventilation or in transient apnea. No consensus exists considering ventilatory mode during PV loop recording. The objective of this study was to investigate the magnitude of any systematic difference of bi-ventricular PV loop variables recorded during mechanical ventilation versus apnea. PV loops were recorded simultaneously from the right ventricle and left ventricle in a closed chest porcine model during mechanical ventilation and in transient apnea (n=72). Variables were compared by regression analyses. Mechanical ventilation versus apnea affected regression coefficients for important PV variables including right ventricular stroke volume (1.22, 95% CI [1.08-1.36], p=0.003), right ventricular ejection fraction (0.90, 95% CI [0.81-1.00], p=0.043) and right ventricular arterial elastance (0.61, 95%CI [0.55-0.68], p<0.0001). Right ventricular pressures and volumes were parallelly shifted with Y-intercepts different from 0. Few left ventricular variables were affected, mainly first derivatives of pressure (dP/dt(max): 0.96, 95% CI [0.92-0.99], p=0.016, and dP/dt(min): 0.92, 95% CI [0.86-0.99], p=0.026), which might be due to decreased heart rate in apnea (Y-intercept -6.88, 95% CI [-12.22; -1.54], p=0.012). We conclude, that right ventricular stroke volume, ejection fraction and arterial elastance were mostly affected by apnea compared to mechanical ventilation. The results motivate future standardization of respiratory modality when measuring PV relationships.
Pulmonary Artery Pulsatility Index in Acute and Chronic Pulmonary Embolism
Background and Objectives: The pulmonary artery pulsatility index (PAPi) is an emerging marker of right ventricular (RV) injury but has not been well investigated in acute pulmonary embolism (PE) or chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to investigate its discriminatory capabilities and ability to detect therapeutic effects in acute PE and CTEPH. Materials and Methods: This was a secondary analysis of data from both experimental studies of autologous PE and human studies of acute PE and CTEPH. PAPi was calculated and compared in (1) PE versus sham and (2) before and after interventions aimed at reducing RV afterload in PE and CTEPH. The correlations between PAPi, cardiac output, and RV to pulmonary artery coupling were investigated. Results: PAPi did not differ between animals with acute PE versus sham, nor was it affected by clot burden (p = 0.673) or at a 30-day follow-up (p = 0.242). Pulmonary vasodilatation with oxygen was associated with a reduction in PAPi (4.9 [3.7–7.8] vs. 4.0 [3.2–5.6], p = 0.016), whereas positive inotropes increased PAPi in the experimental PE. In humans, PAPi did not change consistently with interventions. Balloon pulmonary angioplasty did not significantly increase PAPi (6.5 [4.3–10.7] vs. 9.8 [6.8–14.2], p = 0.1) in patients with CTEPH, and a non-significant reduction in PAPi (4.3 ± 1.6 vs. 3.3 ± 1.2, p = 0.074) was observed in patients with acute PE who received sildenafil. PAPi did not correlate well with cardiac output or measures of RV to pulmonary artery coupling in either species. Conclusions: PAPi did not detect acute, experimental PE or changes as a result of therapeutic interventions in patients with hemodynamically stable acute PE or CTEPH. However, it did change with pharmacological interventions in the experimental PE. Further research should establish its utility in detecting and monitoring RV injury in different clinical phenotypes of acute PE and CTEPH.
Ketone bodies for hemodynamic support in acute pulmonary embolism: a randomized, blinded, controlled animal study
Background Acute pulmonary embolism (PE) is a leading cause of cardiovascular death, primarily due to abrupt increased pulmonary vascular resistance (PVR) leading to acute right ventricular (RV) failure. Ketone bodies, especially 3-hydroxybutyrate (3-OHB), have shown potential to increase cardiac output (CO) and reduce PVR in pulmonary hypertension, suggesting possible benefits in PE. We hypothesized that 3-OHB would induce pulmonary vasorelaxation and increase CO in a porcine model of acute PE. Methods We conducted a randomized, controlled, assessor-blinded study in a porcine model of acute PE. Acute PE was induced, followed by a 3-h infusion of 3-OHB (0.22 g/kg/h, n  = 8) or control (isovolumic saline of equimolar tonicity) ( n  = 8). Hemodynamic parameters were monitored hourly including right heart catheterization and RV pressure–volume loop acquisition. Primary outcome was the difference in CO during 3 h. Ex vivo effects on isolated pulmonary arteries were tested using wire myography. Results Compared with control infusion, 3-OHB did not increase CO significantly (between-group difference: 0.7 [−0.2 to 1.6] L/min, p  = 0.131). However, 3-OHB treatment lowered the PVR/systemic vascular resistance (SVR) ratio (−0.05 [−0.09; −0.01], p  = 0.046) and increased pulmonary artery pulsatility index (5 [2–8], p  = 0.006). Ex vivo, 3-OHB caused vasorelaxation in pre-contracted pulmonary arteries ( p  < 0.0001). Conclusions 3-OHB reduced PVR/SVR ratio, while CO was not significantly increased in a porcine model of acute PE. The present findings demonstrated potential hemodynamic effects in PE. Further studies are needed to explore the translational potential of ketone body therapy in humans with PE.
Balloon pulmonary angioplasty for patients with chronic thromboembolic pulmonary hypertension previously operated by pulmonary endarterectomy
Balloon pulmonary angioplasty improved hemodynamics, walking distance, and World Health Organization functional class in patients with chronic thromboembolic pulmonary hypertension not eligible for pulmonary endarterectomy (Non-PEA) and patients with persistent pulmonary hypertension after PEA (PEA). More mild complications were observed in PEA- compared to Non-PEA.
Detailed characterization of the transcriptome of single B cells in mantle cell lymphoma suggesting a potential use for SOX4
Mantle cell lymphoma (MCL) is a malignancy arising from naive B lymphocytes with common bone marrow (BM) involvement. Although t(11;14) is a primary event in MCL development, the highly diverse molecular etiology and causal genomic events are still being explored. We investigated the transcriptome of CD19 + BM cells from eight MCL patients at single-cell level. The transcriptomes revealed marked heterogeneity across patients, while general homogeneity and clonal continuity was observed within the patients with no clear evidence of subclonal involvement. All patients were SOX11 + CCND1 + CD20 + . Despite monotypic surface immunoglobulin (Ig) κ or λ protein expression in MCL, 10.9% of the SOX11 + malignant cells expressed both light chain transcripts. The early lymphocyte transcription factor SOX4 was expressed in a fraction of SOX11 + cells in two patients and co-expressed with the precursor lymphoblastic marker, FAT1, in a blastoid case, suggesting a potential prognostic role. Additionally, SOX4 was found to identify non-malignant SOX11 – pro-/pre-B cell populations. Altogether, the observed expression of markers such as SOX4, CD27, IgA and IgG in the SOX11 + MCL cells, may suggest that the malignant cells are not fixed in the differentiation state of naïve mature B cells, but instead the patients carry B lymphocytes of different differentiation stages.