Introduction The coronavirus disease 2019 (COVID-19) pandemic has put tremendous pressure on healthcare systems. Most transcatheter aortic valve implantation (TAVI) centres have adopted different... Show moreIntroduction The coronavirus disease 2019 (COVID-19) pandemic has put tremendous pressure on healthcare systems. Most transcatheter aortic valve implantation (TAVI) centres have adopted different triage systems and procedural strategies to serve highest-risk patients first and to minimise the burden on hospital logistics and personnel. We therefore assessed the impact of the COVID-19 pandemic on patient selection, type of anaesthesia and outcomes after TAVI. Methods We used data from the Netherlands Heart Registration to examine all patients who underwent TAVI between March 2020 and July 2020 (COVID cohort), and between March 2019 and July 2019 (pre-COVID cohort). We compared patient characteristics, procedural characteristics and clinical outcomes. Results We examined 2131 patients who underwent TAVI (1020 patients in COVID cohort, 1111 patients in pre-COVID cohort). EuroSCORE II was comparable between cohorts (COVID 4.5 +/- 4.0 vs pre-COVID 4.6 +/- 4.2, p = 0.356). The number of TAVI procedures under general anaesthesia was lower in the COVID cohort (35.2% vs 46.5%, p < 0.001). Incidences of stroke (COVID 2.7% vs pre-COVID 1.7%, p = 0.134), major vascular complications (2.3% vs 3.4%, p = 0.170) and permanent pacemaker implantation (10.0% vs 9.4%, p = 0.634) did not differ between cohorts. Thirty-day and 150-day mortality were comparable (2.8% vs 2.2%, p = 0.359 and 5.2% vs 5.2%, p = 0.993, respectively). Conclusions During the COVID-19 pandemic, patient characteristics and outcomes after TAVI were not different than before the pandemic. This highlights the fact that TAVI procedures can be safely performed during the COVID-19 pandemic, without an increased risk of complications or mortality. Show less
A bicuspid aortic valve (BAV) is a congenital heart defect in which the heart valve between the left ventricle and the aorta consists of two valve flaps instead of the normal three (tricuspid... Show moreA bicuspid aortic valve (BAV) is a congenital heart defect in which the heart valve between the left ventricle and the aorta consists of two valve flaps instead of the normal three (tricuspid aortic valve – TAV). In a large proportion of people with a BAV, calcification of the heart valves or a widening of the aorta occurs early in life. It is not yet clear why patients with a BAV are prone to develop valvular calcification and aortic dilatation. The aim of the research described in this thesis is to study the pathogenesis of aortic valve calcification and aortic dilatation in BAV patients with a focus on the role of endothelial cells in these processes. With the research described in this thesis, we have shown that endothelial cells from BAV patients respond differently than cells from people with a TAV. In addition, the endothelial cell activation in the vascular wall of BAV patients is different and dependent on the blood flow. We found two good tissue culture methods to study heart valve calcification and used them to study the role of the protein FHL2 in this process. Show less
The aim of this article is to review sex differences in aortic stenosis (AS) assessed with multimodality imaging. Echocardiography remains the mainstay imaging technique to diagnose AS and provides... Show moreThe aim of this article is to review sex differences in aortic stenosis (AS) assessed with multimodality imaging. Echocardiography remains the mainstay imaging technique to diagnose AS and provides important insights into the differences between men and women in relation to valve haemodynamic and left-ventricular response. However, echocardiography does not have adequate resolution to provide important insights into sex differences in the degenerative, calcific pathophysiological process of the aortic valve. CT shows that women with AS have more fibrotic changes of the aortic valve whereas men show more calcific deposits. Cardiac magnetic resonance shows that women have left ventricles that are less hypertrophic and smaller compared with those of men, while men have more replacement myocardial fibrosis. These differences may lead to different responses to aortic valve replacement because myocardial diffuse fibrosis but not replacement myocardial fibrosis may regress after the procedure. Sex differences in the pathophysiological process of AS can be assessed using multimodality imaging, assisting in decision -making in these patients. Show less
Background: Left ventricular (LV) kinetic energy (KE) assessment by four-dimensional flow cardiovascular magnetic resonance (4D flow CMR) may offer incremental value over routine assessment in... Show moreBackground: Left ventricular (LV) kinetic energy (KE) assessment by four-dimensional flow cardiovascular magnetic resonance (4D flow CMR) may offer incremental value over routine assessment in aortic stenosis (AS). The main objective of this study is to investigate the LV KE in patients with AS before and after the valve intervention. In addition, this study aimed to investigate if LV KE offers incremental value for its association to the six-minute walk test (6MWT) or LV remodelling post-intervention.Methods: We recruited 18 patients with severe AS. All patients underwent transthoracic echocardiography for mean pressure gradient (mPG), CMR including 4D flow and 6MWT. Patients were invited for post-valve intervention follow-up CMR at 3 months and twelve patients returned for follow-up CMR. KE assessment of LV blood flow and the components (direct, delayed, retained and residual) were carried out for all cases. LV KE parameters were normalised to LV end-diastolic volume (LVEDV).Results: For LV blood flow KE assessment, the metrics including time delay (TD) for peak E-wave from base to mid-ventricle (14 +/- 48 vs. 2.5 +/- 9.75 ms, P=0.04), direct (4.91 +/- 5.07 vs. 1.86 +/- 1.72 mu J, P=0.01) and delayed (2.46 +/- 3.13 vs. 1.38 +/- 1.15 mu J, P=0.03) components of LV blood flow demonstrated a significant change between preand post-valve intervention. Only LV KEi(EDV) (r=-0.53, P<0.01), diastolic KEi(EDV) (r=-0.53, P<0.01) and E-wave KEi(EDV) (r=-0.38, P=0.04) demonstrated association to the 6MWT. However, Pre-operative LV KEi(EDV) (r=0.67, P=0.02) demonstrated association to LV remodelling post valve intervention.Conclusions: LV blood flow KE is associated with 6MWT and LV remodelling in patients with AS. LV KE assessment provides incremental value over routine LV function and pressure gradient (PG) assessment in AS. Show less
This thesis explored the diagnosis, management and prognosis of the most common valvular heart diseases: aortic stenosis (AS) and mitral regurgitation (MR) and enlightened their challenging types:... Show moreThis thesis explored the diagnosis, management and prognosis of the most common valvular heart diseases: aortic stenosis (AS) and mitral regurgitation (MR) and enlightened their challenging types: the discordant low-gradient severe AS and the secondary MR in non-ischemic cardiomyopathy. This thesis provides new insights into the use of fusion aortic valve area index, by incorporating the measurement of left ventricular outflow tract area on cardiac computed tomography in the continuity equation, for the diagnosis of low-gradient AS. For the treatment of low-gradient AS, TAVR is shown to result in reverse LV remodeling and functional recovery. In comparison to other minimal invasive surgical methods it results in less prosthesis-patient-mismatch although paravalvular aortic regurgitation is a caveat. Regarding the diagnostic assessment of secondary MR due to LV dysfunction this thesis concluded that LV GLS reflects the real LV dysfunction while LVEF overestimates LV function without accounting for the forward LV flow. Mitral valve repair offers LV reverse remodeling and increase in forward flow when used for the treatment of this challenging condition. Regarding the prognostication of low-gradient AS and secondary MR this thesis advocates for the evaluation of the valvular calcium on cardiac computed tomography and the evaluation of LV GLS and forward flow that are associated with survival. Show less
The Ross-Konno procedure is a durable solution for multilevel LVOTO in a highly complex patient population with high incidence of previous procedures. High early mortality rates in patients with... Show moreThe Ross-Konno procedure is a durable solution for multilevel LVOTO in a highly complex patient population with high incidence of previous procedures. High early mortality rates in patients with impaired left ventricular function emphasize the importance of patient selection. Freedom from reoperation shows a continuous attrition rate. Reoperation for autograft failure may occur late after the Ross-Konno procedure. Show less
