OBJECTIVES: Genetic defects associated with bicuspid aortopathy have been infrequently analysed. Our goal was to examine the prevalence of rare genetic variants in patients with a bicuspid aortic valve (BAV) with a root phenotype using next-generation sequencing technology. METHODS: We investigated a total of 124 patients with BAV with a root dilatation phenotype who underwent aortic valve ± proximal aortic surgery at a single institution (BAV database, n = 812) during a 20-year period (1995–2015). Cross-sectional follow-up revealed 63 (51%) patients who were still alive and willing to participate. Systematic follow-up visits were scheduled from March to December 2015 and included aortic imaging as well as peripheral blood sampling for genetic testing. Next-generation sequencing libraries were prepared using a custom-made HaloPlex HS gene panel and included 20 candidate genes known to be associated with aortopathy and BAV. The primary end-point was the prevalence of genetic defects in our study cohort. RESULTS: A total of 63 patients (mean age 46 ± 10 years, 92% men) with BAV root phenotype and mean post-aortic valve replacement follow-up of 10.3 ± 4.9 years were included. Our genetic analysis yielded a wide spectrum of rare, potentially or likely pathogenic variants in 19 (30%) patients, with NOTCH1 variants being the most common (n = 6). Moreover, deleterious variants were revealed in AXIN1 (n = 3), NOS3 (n = 3), ELN (n = 2), FBN1 (n = 2), FN1 (n = 2) and rarely in other candidate genes. CONCLUSIONS: Our preliminary study demonstrates a high prevalence and a wide spectrum of rare genetic variants in patients with the BAV root phenotype, indicative of the potentially congenital origin of associated aortopathy in this specific BAV cohort.

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine known to play a major role in inflammatory diseases such as myocardial infarction (MI), where its expression increases. Cardio-protective functions of MIF during ischemia have been reported. Recently, the structurally related MIF-2 was identified and similar effects are assumed. We wanted to further investigate the role of MIF and MIF-2 on inflammatory processes during MI. Therefore, we subjected mice to experimentally induced MI by coronary occlusion for one and five days. During the acute phase of MI, the gene expression of Mif was upregulated in the infarct zone, whereas Mif-2 was downregulated, suggesting a minor role of MIF-2. Simulating ischemic conditions or mechanical stress in vitro, we demonstrated that Mif expression was induced in resident cardiac cells. To investigate possible auto-/paracrine effects, cardiomyocytes and cardiac fibroblasts were individually treated with recombinant murine MIF, which in turn induced Mif expression and the expression of pro-inflammatory genes in cardiac fibroblasts. Cardiomyocytes did not respond to recombinant MIF with pro-inflammatory gene expression. While MIF stimulation alone did not change the expression of pro-fibrotic genes in cardiac fibroblasts, ischemia reduced their expression. Mimicking the increased MIF levels during MI, we exposed cardiac fibroblasts to simulated ischemia in the presence of MIF, which led to further reduced expression of pro-fibrotic genes. The presented data show that MIF was expressed by resident cardiac cells during MI. In vitro, Mif expression was induced by different external stimuli in cardiomyocytes and cardiac fibroblasts. Addition of recombinant MIF protein increased the expression of pro-inflammatory genes in cardiac fibroblasts including Mif expression itself. Thereby, cardiac fibroblasts may amplify Mif expression during ischemia promoting cardiomyocyte survival.

Systolic heart failure is frequently accompanied by a relevant functional mitral valve regurgitation (FMR) which develops as a direct sequela of the ongoing left ventricular remodelling. The severity of mitral regurgitation is further aggravated by progressive left ventricular enlargement causing leaflet tethering and reduced systolic leaflet movement. The prognosis of such patients is obviously limited by an underlying left ventricular disease, and the correction of secondary FMR has been previously suggested as predominantly ‘cosmetic’ surgery in the setting of ongoing cardiomyopathy. Inferior results of an isolated annuloplasty in type IIIb FMR supported the philosophy of malignant course of progressive cardiomyopathy and resulted in increasingly restricted indications for mitral valve surgery for FMR in the guidelines. The lack of a standardized pathophysiological approach to correct type IIIb FMR led to the development of valve replacement strategy and edge-to-edge catheter-based mitral valve procedures, which became the most frequent procedures in the FMR setting in Europe. Modern mitral valve surgery combines the advantages of 3-dimensional endoscopic minimally invasive surgical approach with standardized subannular repair to address the pathophysiological background of type IIIb FMR. The perioperative results have been significantly improved, and there is a growing evidence of improved long-term stability of subannular repair procedures as compared to isolated annuloplasty. This review article aims to present the current state-of-the-art of the modern mitral valve surgery in FMR and provides suggestions for future trials analysing the potential advantages in these patients.

Perforation of the subannular left ventricular outflow tract (LVOT) represents an uncommon but almost invariably fatal transcatheter aortic valve implantation (TAVI)-associated complication. The risk factors to predict the occurrence of this devastating complication, particularly in relation to specific LVOT anatomy, have not yet been systematically analysed. We aimed to evaluate the pathophysiological background and possible risk factors for the occurrence of subannular LVOT perforation. A total of 6 (0.7%) consecutive patients (78.8 ± 3.3 years, 83% women) with subannular LVOT perforation complicating TAVI procedure were identified from our institutional TAVI registry, including 900 consecutive patients who underwent TAVI procedure at a single institution between January 2009 and July 2015. Only patients with an intraoperatively confirmed LVOT perforation were included. The computed tomography (CT)-guided analysis of aortic root/LVOT morphology revealed subannular calcification in close proximity of the anatomically weakest region of muscular LVOT (i.e. in the region of the muscular LVOT between the left fibrous trigone and the left/right commissure) in 5/6 (83%) patients. Moreover, significant annular asymmetry >20% was present in 4/6 (67%) patients and was combined with a severe asymmetric hypertrophy of muscular LVOT. Subannular calcification in close proximity of the anatomically unprotected muscular LVOT might represent an important risk factor for the occurrence of subannular LVOT injury. Precise CT-based analysis of patient-specific aortic root anatomy/subannular calcification patterns may be helpful to predict this TAVI-associated complication preoperatively and hence to avoid it in future patients.