Fibrosis and expression of extracellular matrix proteins in human interventricular septum in aortic valve stenosis and regurgitation

Valvular heart disease leads to ventricular pressure and/or volume overload. Pressure overload leads to fibrosis, which might regress with its resolution, but the limits and details of this reverse remodeling are not known. To gain more insight into the extent and nature of cardiac fibrosis in valve disease, we analyzed needle biopsies taken from the interventricular septum of patients undergoing surgery for valve replacement focusing on the expression and distribution of major extracellular matrix protein involved in this process. Proteomic analysis performed using mass spectrometry revealed an excellent correlation between the expression of collagen type I and III, but there was little correlation with the immunohistochemical staining performed on sister sections, which included antibodies against collagen I, III, fibronectin, sarcomeric actin, and histochemistry for wheat germ agglutinin. Surprisingly, the immunofluorescence intensity did not correlate significantly with the gold standard for fibrosis quantification, which was performed using Picrosirius Red (PSR) staining, unless multiplexed on the same tissue section. There was also little correlation between the immunohistochemical markers and pressure gradient severity. It appears that at least in humans, the immunohistochemical pattern of fibrosis is not clearly correlated with standard Picrosirius Red staining on sister sections or quantitative proteomic data, possibly due to tissue heterogeneity at microscale, comorbidities, or other patient-specific factors. For precise correlation of different types of staining, multiplexing on the same section is the best approach.

Outcomes of aortic valve repair in children stratified by complexity: Which outcome for which lesion?

OBJECTIVE

Aortic valvuloplasty frequency has significantly increased over the past 15 years. Surgical repair varies in complexity depending on valvular lesions. Our aim is to report results on the whole spectrum of aortic valvuloplasty techniques.

METHODS

All children who consecutively underwent aortic valvuloplasty for aortic stenosis and/or aortic insufficiency between January 2006 and December 2020 at Necker Sick Children's Hospital (Paris, France) were included in a retrospective cohort study. Aortic valvuloplasty techniques were classified into 3 difficulty levels: (1) simple repair, corresponding to commissurotomy and/or shaving in aortic stenosis (AS) in neonates (group 1) and children >1 month (group 2); (2) intermediate-complexity repair, corresponding to commissuroplasty, leaflet resuspension, and fenestration closure in aortic insufficiency (leaflet prolapse in connective tissue disease, isolated leaflet prolapse and Laubry-Pezzi groups); and (3) complex repair requiring a pericardial patch to restore a functional aortic valve in mixed aortic valve disease (bicuspidization with neocommissure and cusp extension groups).

RESULTS

During the study period, 324 children underwent aortic valvuloplasty. Survival and freedom from aortic valve reintervention at 10 years were, respectively, 86.1% and 50.9% in neonates with AS, 95.2% and 71.7% in children >1 month with AS, 93.8% and 79.5% in leaflet prolapse in connective tissue disease, 97.7% and 91.9% in isolated leaflet prolapse, 100% and 88% in those with Laubry-Pezzi syndrome, 97.4% and 84.8% in bicuspidization with neocommissure, and 100% and 54.2% in the cusp extension.

CONCLUSIONS

Durability of aortic valvuloplasty techniques is satisfactory and offers the possibility to delay the Ross procedure, regardless of the lesion's complexity.

Surgical aortic valve replacement etiologies, hemodynamics, and outcomes in 1346 patients from the Malaysian heart centre

BACKGROUND

This study examined the characteristics and outcomes of surgical aortic valve replacement (SAVR) both isolated and in combination with other cardiac surgery in Malaysia from 2015 to 2021.

METHODS

This was a retrospective study of 1346 patients analyzed on the basis of medical records, echocardiograms and surgical reports. The overall sample was both considered as a whole and divided into aortic stenosis (AS)/aortic regurgitation (AR)-predominant and similar-severity subgroups.

RESULTS

The most common diagnosis was severe AS (34.6%), with the 3 most common etiologies being bicuspid valve degeneration (45.3%), trileaflet valve degeneration (36.3%) and rheumatic valve disease (12.2%). The second most common diagnosis was severe AR (25.5%), with the most common etiologies being root dilatation (21.0%), infective endocarditis (IE) (16.6%) and fused prolapse (12.2%). Rheumatic valve disease was the most common mixed disease. A total of 54.5% had AS-predominant pathology (3 most common etiologies: bicuspid valve degeneration valve, degenerative trileaflet valve and rheumatic valve disease), 36.9% had AR-predominant pathology (top etiologies: root dilatation, rheumatic valve disease and IE), and 8.6% had similar severity of AS and AR. Overall, 62.9% of patients had trileaflet valve morphology, 33.3% bicuspid, 0.6% unicuspid and 0.3% quadricuspid. For AS, the majority were high-gradient severe AS (49.9%), followed by normal-flow low-gradient (LG) severe AS (10.0%), paradoxical low-flow (LF)-LG severe AS (6.4%) and classical LF-LG severe AS (6.1%). The overall in-hospital and total 1-year mortality rates were 6.4% and 14.8%, respectively. Pure severe AS had the highest mortality. For AS-predominant pathology, the etiology with the highest mortality was trileaflet valve degeneration; for AR-predominant pathology, it was dissection. The overall survival probability at 5 years was 79.5% in all patients, 75.7% in the AS-predominant subgroup, 83.3% in the AR-predominant subgroup, and 87.3% in the similar-severity subgroup.

CONCLUSIONS

The 3 most common causes of AS- predominant patients undergoing SAVR is bicuspid valve degeneration, degenerative trileaflet valve and rheumatic and for AR-predominant is root dilatation, rheumatic and IE. Rheumatic valve disease is an important etiology in our SAVR patients especially in mixed aortic valve disease. Study registration IJNREC/562/2022.

Aortic Regurgitation: Review of the Diagnostic Criteria and the Management Guidelines

PURPOSE OF REVIEW

The evaluation of aortic regurgitation (AR) has advanced from physical examination and angiography towards evidence based non-invasive quantitative methods, primarily with echocardiography and more recently with cardiac magnetic resonance (CMR). This review highlights the guidelines and recent evidence in the diagnosis and management of AR; and outlines future areas of research.

RECENT FINDINGS

Contemporary large cohorts of AR patients studied with echocardiography and CMR suggest that the left ventricular remodeling and systolic function triggers for intervention may be lower than previously recommended in the guidelines and emphasize the importance of LV volumes in risk stratification. Important gaps of knowledge in the quantitation of AR severity and patient risk stratification were fulfilled recently. Potential thresholds for intervention using ventricular volumes and CMR quantitative findings were recently described. The criteria for what constitutes hemodynamically significant AR and the optimal timing of intervention AR deserve further study.

A Role for Peroxisome Proliferator-Activated Receptor Gamma Agonists in Counteracting the Degeneration of Cardiovascular Grafts

ABSTRACT

Aortic valve replacement for severe stenosis is a standard procedure in cardiovascular medicine. However, the use of biological prostheses has limitations especially in young patients because of calcifying degeneration, resulting in implant failure. Pioglitazone, a peroxisome proliferator-activated receptor gamma (PPAR-gamma) agonist, was shown to decrease the degeneration of native aortic valves. In this study, we aim to examine the impact of pioglitazone on inflammation and calcification of aortic valve conduits (AoC) in a rat model. Cryopreserved AoC (n = 40) were infrarenally implanted into Wistar rats treated with pioglitazone (75 mg/kg chow; n = 20, PIO) or untreated (n = 20, controls). After 4 or 12 weeks, AoC were explanted and analyzed by histology, immunohistology, and polymerase chain reaction. Pioglitazone significantly decreased the expression of inflammatory markers and reduced the macrophage-mediated inflammation in PIO compared with controls after 4 (P = 0.03) and 12 weeks (P = 0.012). Chondrogenic transformation was significantly decreased in PIO after 12 weeks (P = 0.001). Calcification of the intima and media was significantly reduced after 12 weeks in PIO versus controls (intima: P = 0.008; media: P = 0.025). Moreover, echocardiography revealed significantly better functional outcome of the AoC in PIO after 12 weeks compared with control. Interestingly, significantly increased intima hyperplasia could be observed in PIO compared with controls after 12 weeks (P = 0.017). Systemic PPAR-gamma activation prevents inflammation as well as intima and media calcification in AoC and seems to inhibit functional impairment of the implanted aortic valve. To further elucidate the therapeutic role of PPAR-gamma regulation for graft durability, translational studies and long-term follow-up data should be striven for.

Aortic Diameters and Mild Functional Aortic Regurgitation in Hypertensive and Normotensive People: Do They Carry the Same Meaning?

OBJECTIVES

The association between the aortic root diameter and aortic regurgitation in hypertensive and normotensive people is still disputed, and the underlying mechanisms remain to be clearly elucidated. We aimed to investigate the relationship between the aortic root diameter and trivial to mild functional aortic regurgitation in never-treated hypertensive patients with a new diagnosis compared with healthy normotensive participants.

METHODS

A total of 182 hypertensives and 232 age-matched normotensives were included in the study. Anthropometric and office blood pressure (BP) measurements, echocardiography, and a carotid stiffness assessment were performed in all of the participants. Aortic measures for the annulus, sinuses of Valsalva, sinotubular junction, and ascending aorta were taken in late diastole according to the leading-edge method.

RESULTS

The mean age of all participants was 52 years. Hypertensive patients had a significantly higher body surface area, mean arterial pressure, and pulse pressure (P < .0001) than normotensive participants. Annulus and sinotubular junction diameters adjusted for confounders and indexed to the body surface area were significantly higher in normotensives than in hypertensives. The prevalence of functional aortic regurgitation was higher in hypertensives (34.8% versus 15.4%; P < .0001). Among the hypertensives, no difference in aortic diameters was found between patients with or without functional aortic regurgitation, whereas normotensives with functional aortic regurgitation had larger aortic root diameters. Aging and BP among the hypertensives were the main determinants of functional aortic regurgitation.

CONCLUSIONS

Hypertensive patients had a smaller indexed aortic root diameter than normotensive participants but had a higher prevalence of trivial to mild functional aortic regurgitation. The aging process is the main determinant of functional aortic regurgitation in both groups, but high BP also plays an important role in hypertensives.

Natural history of echocardiographic abnormalities in mucopolysaccharidosis III

BACKGROUND

Mucopolysaccharidosis (MPS) type III, Sanfilippo Syndrome, is an autosomal recessive lysosomal storage disorder. MPS I and II patients often develop cardiac involvement leading to early mortality, however there are limited data in MPS III. The objective of this study is to describe cardiac abnormalities in a large group of MPS III patients followed in a longitudinal natural history study designed to determine outcome measures for gene transfer trials.

METHODS

A single center study of MPS III patients who were enrolled in the Nationwide Children's Hospital natural history study in 2014. Two cardiologists reviewed all patient echocardiograms for anatomic, valvular, and functional abnormalities. Valve abnormalities were defined as abnormal morphology, trivial mitral regurgitation (MR) with abnormal morphology or at least mild MR, and any aortic regurgitation (AR). Abnormal left ventricular (LV) function was defined as ejection fraction < 50%. Group comparisons were assessed using two-sample t-tests or Wilcoxon rank sum tests for continuous variables and chi-square or Fisher's exact tests for categorical variables.

RESULTS

Twenty-five patients, 15 Type A and 10 Type B MPS III, underwent 45 echocardiograms. Fifteen patients (60%) demonstrated an abnormal echocardiographic finding with age at first abnormal echocardiogram within the study being 6.8 ± 2.8 years. Left-sided valve abnormalities were common over time: 7 mitral valve thickening, 2 mitral valve prolapse, 16 MR (8 mild, 8 trivial), 3 aortic valve thickening, and 9 AR (7 mild, 2 trivial). Two patients had asymmetric LV septal hypertrophy. No valvular stenosis or ventricular function abnormalities were noted. Incidental findings included: mild aortic root dilation (2), bicommissural aortic valve (1), and mild tricuspid regurgitation (3).

CONCLUSIONS

Individuals with Sanfilippo A and B demonstrate a natural history of cardiac involvement with valvular abnormalities most common. In short-term follow up, patients demonstrated only mild progression of abnormalities, none requiring intervention. Valvular disease prevalence is similar to MPS I and II, but appears less severe. These findings raise no specific concerns for gene transfer trials in patients in this age range.

New morphological classification of congenital quadricuspid aortic valve and its histopathologic features

We report a 52-year-old male patient who had a quadricuspid aortic valve (QAV) associated with aortic regurgitation (AR) and left ventricular hypertrophy (LVH). A new accessory cusp (ACC) with maximum thickness than other cusps was located between right coronary cusp (RCC) and left coronary cusp (LCC). The histopathological features revealed markedly thickened and distorted cusp architecture with fibrosis and/or myxomatous degeneration in both non-coronary cusp (NCC) and ACC. Two equal sizes for larger cusps (RCC and NCC) and two equal sizes for smaller cusps (LCC and ACC) were obtained. This QAV belonged to type C QAV of Hurwitz's classification, but also suggested as a modified type III of Jagannath's classification or a new type V of Nakamura's classification by locating ACC between RCC and LCC.

Long-Term Results of Aortic Root Surgery in Marfan Syndrome Patients: A Single-Center Experience

BACKGROUND AND AIM OF THE STUDY

The study aim was to compare long-term results of Marfan syndrome (MFS) patients affected by aortic root disease undergoing aortic root replacement with the Bentall or David operation.

METHODS

Since 1994, a total of 59 patients has been followed at the authors' Marfan Center, having undergone either a Bentall operation (Bentall group, n = 30) or a David operation (David group, n = 29).

RESULTS

No operative mortality was recorded. After 20 years (mean follow up 97 ± 82 months; range 1 to 369 months) no prosthesis-related major bleeding or thromboembolic events had been observed; the 20-year survival was 94 ± 6% in the Bentall group, and 100% in the David group (p = 0.32). Freedom from reintervention for aortic valve dysfunction was 100% in the Bentall group, and 75 ± 13% in the David group (p = 0.04). This inter-group difference became relevant after the first eight-year period of follow-up, and was mainly associated with a particular familiar genetic phenotype involving three out of four reoperated patients. Freedom from all-cause death, myocardial infarction, stroke, prosthetic valve-related complications, and reintervention on any aortic segment was 69 ± 12% in the Bentall group, and 67 ± 14% in the David group (p = 0.33).

CONCLUSIONS

The Bentall and David operations are both associated with satisfactory long-term results in MFS patients. The low rate of valve prosthesis-related complications suggested that the Bentall operation would continue to be a standard surgical treatment. The reimplantation technique, adopted for less-dilated aortas, provides satisfactory freedom from reoperation. Careful attention should be paid to the reimplantation technique in patients affected by a serious familiar genetic phenotype.

Early Activation of Growth Pathways in Mitral Leaflets Exposed to Aortic Regurgitation: New Insights from an Animal Model

BACKGROUND AND AIM OF THE STUDY

Mitral leaflet enlargement in patients with chronic aortic regurgitation (AR) has been identified as an adaptive mechanism potentially able to prevent functional mitral regurgitation (FMR) in response to left ventricular (LV) dilatation. The timing of valve enlargement is not known, and the related mechanisms are largely unexplored.

METHODS

AR was induced in 58 rats, and another 54 were used as sham controls. Animals were euthanized at different time points after AR creation (48 h, one week, and three months), and AR severity, FMR and LV dilatation were assessed using echocardiography. Mitral valves were harvested to document the reactivation of embryonic growth pathways.

RESULTS

AR animals had increased LV dimensions and mitral annulus size. No animal developed FMR. No change in leaflet length or thickness was seen at 48 h; however, anterior mitral leaflets were longer and thicker in AR animals at one week and three months. Molecular changes were present early (at 48 h and at one week), with positive staining for transforming growth factor-b1 (TGF-b1), Alpha-smooth muscle actin (α-SMA) and matrix metalloproteinase-2 (MMP-2), which suggested active matrix remodeling. Increased gene expression for collagen 1, TGF-β1, α-SMA and MMP-2 was found in the mitral valve at 48 h and at one week, but after three months their expression had returned to normal.

CONCLUSIONS

This model of AR induces active expansion and thickening of the mitral leaflets. Growth signals are expressed acutely, but not at three months, which suggests that most of this enlargement occurs at an early stage. The stimulation of valvular growth could represent a new strategy for the prevention of FMR.

[PULMONARY AUTOGRAFT OPERATION IN PEDIATRIC PATIENTS]

Experience of performance of a pulmonary autograft operation (PAO, оperation of Ross) was analyzed, results were estimated, the ways of overcoming a procedure conduction problems were determined. Remote result was investigated in 151 patients: the aortal valve stenosis was diagnosed in 99 (65.6%) patients, insufficiency - in 42 (27.8%), combined aortal valve failure - in 10 (6.6%). Hospital lethality have constituted 3.6%, and a general one – 7.9%. Reoperations were performed in 52 patients. PAO constitutes one of surgical procedures for the aortal valve failure in children of different age. Improvement of surgical technique and application of a new procedures have promoted improvement of the investigation results – lethality lowering from 15.1 to 0.8%. Application of surgical modifications with the aortal radix strengthening have reduced the reoperations on neaortal valve risk trustworthy.

[Not Available]

The investigation objective was to improve the immediate results of surgical treatment of the aortal valve failure, applying minimization of operative trauma and, accordingly, rapid functional rehabilitation of patients. The aortal valve prosthesis, using minimally invasive access, was conducted in 44 patients. There was proved, that conduction of ministernotomy for strict indications is effective and have significant advantages, com' paring with classic median sternotomy, because it provides minimal surgical trauma, preservation of the thoracic cage frame, and better cosmetic effect.

Structural and Histochemical Alterations in the Aortic Valves of Elderly Patients: A Comparative Study of Aortic Stenosis, Aortic Regurgitation, and Normal Valves

The aim of this study was to reveal the pathogenesis of aortic stenosis (AS) and regurgitation (AR) by comparing differences in mechanical and biochemical alterations. We applied scanning acoustic microscopy (SAM) to measure the speed of sound (SOS) through valves to estimate the elasticity and monitor sensitivity to protease treatment, as the SOS is correlated with the stiffness of materials, which is reduced after digestion by proteases. The fibrosa of both the AS and AR groups were stiffer than the fibrosa of the normal group. The AR group displayed significantly stiffer fibrosa than the AS group, with the exception of calcified areas. The AS group showed significantly decreased SOS values following protease digestion, whereas the AR showed little reduction. The AS group presented type III collagen in the fibrosa and the ventricularis. In the AR group, both type I collagen and type III collagen coexisted in the fibrosa and the ventricularis. Upon immunostaining for advanced glycation end-products, the AS group showed sparse, weak staining, whereas the AR group presented a strong, band-like positive reaction in the fibrosa. In conclusion, tissue remodelling associated with damage and repair is associated with AS pathogenesis, whereas static chemical alterations with slow collagen turnover induce AR.

Pathological Investigation of Congenital Bicuspid Aortic Valve Stenosis, Compared with Atherosclerotic Tricuspid Aortic Valve Stenosis and Congenital Bicuspid Aortic Valve Regurgitation

Background

Congenital bicuspid aortic valve (CBAV) is the main cause of aortic stenosis (AS) in young adults. However, the histopathological features of AS in patients with CBAV have not been fully investigated.

Methods and Results

We examined specimens of aortic valve leaflets obtained from patients who had undergone aortic valve re/placement at our institution for severe AS with CBAV (n = 24, CBAV-AS group), severe AS with tricuspid aortic valve (n = 24, TAV-AS group), and severe aortic regurgitation (AR) with CBAV (n = 24, CBAV-AR group). We compared the histopathological features among the three groups. Pathological features were classified using semi-quantitative methods (graded on a scale 0 to 3) by experienced pathologists without knowledge of the patients’ backgrounds. The severity of inflammation, neovascularization, and calcium and cholesterol deposition did not differ between the CBAV-AS and TAV-AS groups, and these four parameters were less marked in the CBAV-AR group than in the CBAV-AS (all p<0.01). Meanwhile, the grade of valvular fibrosis was greater in the CBAV-AS group, compared with the TAV-AS and CBAV-AR groups (both p<0.01). In AS patients, thickness of fibrotic lesions was greater on the aortic side than on the ventricular side (both p<0.01). Meanwhile, thickness of fibrotic lesions was comparable between the aortic and ventricular sides in CBAV-AR patients (p = 0.35).

Conclusions

Valvular fibrosis, especially on the aortic side, was greater in patients with CBAV-AS than in those without, suggesting a difference in the pathogenesis of AS between CBAV and TAV.

Morphological Characteristics and Calcification of the Native Aortic Valve and the Relation to Significant Aortic Regurgitation after CoreValve TAVI

BACKGROUND AND AIM OF THE STUDY

Aortic regurgitation (AR) is a frequent and life-limiting complication after transcatheter aortic valve implantation (TAVI). The study aim was to relate post-TAVI AR, using a self-expandable stent, to detailed baseline anatomical and morphological characteristics of the native aortic valve.

METHODS

A total of 82 patients (40 males, 42 females; mean age 80 ± 7 years) who received a Medtronic CoreValve implant was included. Aortic root morphology, aortic annulus and implant size mismatch, implant position, extent of aortic annulus and leaflet calcification, the connected sub-annular calcification volume, and their distribution were quantified based on computed tomography scan analysis. AR following TAVI was quantified using standardized angiography and echocardiography.

RESULTS

The mean logistic EuroSCORE of all patients was 16.9 ± 11.1%. According to angiography and echocardiography, 41% and 39% respectively, of the patients had AR grade ≥2. The two methods correlated moderately (Spearman's ρ = 0.51, p <0.001). The maximal diameter of the native annulus was larger in patients with significant AR after TAVI based on echocardiography (28.0 mm versus 26.8 mm, p = 0.059). Excessive calcification, especially on the left coronary cusp, was present in patients with significant AR, based on angiography (AR ≥II 71.0 mm3 versus AR <II 26.3 mm3, p = 0.001) as well as on echocardiography (AR ≥II 59.9 mm3 versus AR <II 34.0 mm3, p = 0.016).

CONCLUSIONS

Of the evaluated characteristics, a larger volume of calcification (especially on the left coronary cusp) is most related to the development of significant AR (grade II-IV) following implantation, when quantified by both angiography and echocardiography.

Relation of Aortic Valve Morphologic Characteristics to Aortic Valve Insufficiency and Residual Stenosis in Children With Congenital Aortic Stenosis Undergoing Balloon Valvuloplasty

Aortic valve morphology has been invoked as intrinsic to outcomes of balloon aortic valvuloplasty (BAV) for congenital aortic valve stenosis. We sought to use aortic valve morphologic features to discriminate between valves that respond favorably or unfavorably to BAV, using aortic insufficiency (AI) as the primary outcome. All patients who underwent BAV at 2 large-volume pediatric centers from 2007 to 2014 were reviewed. Morphologic features assessed on pre-BAV echo included valve pattern (unicuspid, functional bicuspid, and true bicuspid), leaflet fusion length, leaflet excursion angle, and aortic valve opening area and on post-BAV echo included leaflet versus commissural tear. Primary end point was increase in AI (AI+) of ≥2°. Eighty-nine patients (median age 0.2 years) were included in the study (39 unicuspid, 41 functional bicuspid, and 9 true bicuspid valves). Unicuspid valves had a lower opening area (p <0.01) and greater fusion length (p = 0.01) compared with functional and true bicuspid valves. Valve gradient pre-BAV and post-BAV were not different among valve patterns. Of the 16 patients (18%) with AI+, 14 had leaflet tears (odds ratio 13.9, 3.8 to 50). True bicuspid valves had the highest rate (33%) of AI+. On multivariate analysis, leaflet tears were associated with AI+, with larger opening area pre-BAV and lower fusion length pre-BAV. AI+ was associated with larger pre-BAV opening area. Gradient relief was associated with reduced angle of excursion. Valve morphology influences outcomes after BAV. Valves with lesser fusion and larger valve openings have higher rates of leaflet tears which in turn are associated with AI.

Histological Validation of measurement of diffuse interstitial myocardial fibrosis by myocardial extravascular volume fraction from Modified Look-Locker imaging (MOLLI) T1 mapping at 3 T

BACKGROUND

Gadolinium (Gd) Extracellular volume fraction (ECV) by Cardiovascular Magnetic Resonance (CMR) has been proposed as a non-invasive method for assessment of diffuse myocardial fibrosis. Yet only few studies used 3 T CMR to measure ECV, and the accuracy of ECV measurements at 3 T has not been established. Therefore the aims of the present study were to validate measurement of ECV by MOLLI T1 mapping by 3 T CMR against fibrosis measured by histopathology. We also evaluated the recently proposed hypothesis that native-T1 mapping without contrast injection would be sufficient to detect fibrosis.

METHODS

31 patients (age = 58 ± 17 years, 77% men) with either severe aortic stenosis (n = 12) severe aortic regurgitation (n = 9) or severe mitral regurgitation (n = 10), all free of coronary artery disease, underwent 3 T-CMR with late gadolinium enhancement (LGE) and pre- and post-contrast MOLLI T1 mapping and ECV computation, prior to valve surgery. LV biopsies were performed at the time of surgery, a median 13 [1-30] days later, and stained with picrosirius red. Pre-, and post-contrast T1 values, ECV, and amount of LGE were compared against magnitude of fibrosis by histopathology by Pearson correlation coefficients.

RESULTS

The average amount of interstitial fibrosis by picrosirius red staining in biopsy samples was 6.1 ± 4.3%. ECV computed from pre-post contrast MOLLI T1 time changes was 28.9 ± 5.5%, and correlated (r = 0.78, p < 0.001) strongly with the magnitude of histological fibrosis. By opposition, neither amount of LGE (r = 0.17, p = 0.36) nor native pre-contrast myocardial T1 time (r = -0.18, p = 0.32) correlated with fibrosis by histopathology.

CONCLUSIONS

ECV determined by 3 T CMR T1 MOLLI images closely correlates with histologically determined diffuse interstitial fibrosis, providing a non-invasive estimation for quantification of interstitial fibrosis in patients with valve diseases. By opposition, neither non-contrast T1 times nor the amount of LGE were indicative of the magnitude of diffuse interstitial fibrosis measured by histopathology.

The quadricuspid aortic valve

The quadricuspid aortic valve is a very rare congenital defect that may be an isolated entity or associated with a multitude of cardiovascular abnormalities. Isolated cases usually manifest late in life with the complication of aortic regurgitation, which can be delayed by early valve replacement. We present a case of quadricuspid aortic valve associated with truncus arteriosus, ventricular septal defect, and interrupted aortic arch.

[Expediency of application of miniinvasive access in prosthesis of aortal valve]

The literature data, concerning expediency of miniinvasive access in aortal valve prosthesis for its failures of various etiologies, are analyzed. Advantages and failures, occurring while its application, are discussed. Own clinical observation of successful conduction of operative intervention for aortal valve failure, using miniinvasive access, is adduced.

Echocardiographic versus histologic findings in Marfan syndrome

This retrospective study attempted to establish the prevalence of multiple-valve involvement in Marfan syndrome and to compare echocardiographic with histopathologic findings in Marfan patients undergoing valvular or aortic surgery. We reviewed echocardiograms of 73 Marfan patients who underwent cardiovascular surgery from January 2004 through October 2009. Tissue histology was available for comparison in 29 patients. Among the 73 patients, 66 underwent aortic valve replacement or the Bentall procedure. Histologic findings were available in 29 patients, all of whom had myxomatous degeneration. Of 63 patients with moderate or severe aortic regurgitation as determined by echocardiography, 4 had thickened aortic valves. The echocardiographic findings in 18 patients with mitral involvement included mitral prolapse in 15. Of 11 patients with moderate or severe mitral regurgitation as determined by echocardiography, 4 underwent mitral valve repair and 7 mitral valve replacement. Histologic findings among mitral valve replacement patients showed thickened valve tissue and myxomatous degeneration. Tricuspid involvement was seen echocardiographically in 8 patients, all of whom had tricuspid prolapse. Two patients had severe tricuspid regurgitation, and both underwent repair. Both mitral and tricuspid involvement were seen echocardiographically in 7 patients. Among the 73 patients undergoing cardiac surgery for Marfan syndrome, 66 had moderate or severe aortic regurgitation, although their valves manifested few histologic changes. Eighteen patients had mitral involvement (moderate or severe mitral regurgitation, prolapse, or both), and 8 had tricuspid involvement. Mitral valves were most frequently found to have histologic changes, but the tricuspid valve was invariably involved.

Supravalvular aortic stenosis in adult with anomalies of aortic arch vessels and aortic regurgitation

The supravalvular aortic stenosis is a rare congenital heart defect being very uncommon in adults. We present a case of supravalvular aortic stenosis in adult associated with anomalies of the aortic arch vessels and aortic regurgitation, which was submitted to aortic valve replacement and arterioplasty of the ascending aorta with a good postoperative course.

Ruptured giant mitral valve aneurysm: an unexpected finding in a diabetic patient with dyspnea and new-onset atrial fibrillation

Mitral valve aneurysm (MVA) is a rare valve disease. The case is reported of pathologically proven MVA in a 61-year-old diabetic male with chronic alcoholic liver disease who presented with dyspnea and new-onset atrial fibrillation, without clinical elements of current or recent infection. Transthoracic echocardiography revealed a 'cystic' formation of the anterior mitral leaflet (AML) with mild mitral regurgitation (MR) and aortic regurgitation (AR) hitting the AML. Transesophageal echocardiography (TEE) showed clearly that the formation on the AML was a valve aneurysm, and depicted the site of aneurysm rupture with an additional jet of MR through the rupture. Following mitral valve replacement, pathology of the excised valve showed chronic bacterial endocarditis with calcified bacterial colonies, myxomatous changes with fibrinoid dissection of lamina fibrosa, and neovascularization of the leaflet. The mechanisms of MVA formation are discussed, together with its potential complications, diagnostic modalities and therapeutic strategies. The present case emphasizes that MVA is often a remnant of endocarditis, even when the latter is clinically silent and undiagnosed. The importance of chronic AR directed towards the AML as a predisposing condition for MVA formation is also underlined in this case. The superiority of TEE in providing a full exploration of the mitral valve morphology is verified.

Aortic dimensions in relation to bicuspid and tricuspid aortic valve pathology

BACKGROUND AND AIM OF THE STUDY

The relationship between aortic valve pathology and the aortic root and ascending aortic dimensions in cardiac surgery patients is unclear, and its clarification was the objective of this study.

METHODS

The severity of valve pathology, whether aortic valve stenosis (AS) or aortic valve regurgitation (AR), and the aortic dimensions (aortic root and ascending aorta) were prospectively evaluated with echocardiography in 500 consecutive patients with tricuspid aortic valve (TAV) or bicuspid aortic valve (BAV) who had undergone surgery due to aortic valve and/or ascending aortic disease.

RESULTS

The distribution of valve pathology was similar in TAV and BAV patients when the aorta was non-dilated. However, when the aorta was dilated, AS was seen predominantly in BAV patients (n = 76) compared to TAV patients (n = 2). In TAV and BAV patients with non-dilated aortas, an increased severity of valve pathology was associated with smaller dimensions of the aortic root and the ascending aorta. In TAV and BAV patients with dilated aortas, an increase in the severity of AR was associated with a decreasing dimension of the ascending aorta but an increasing dimension of the aortic root. In BAV patients with aneurysm, the severity of AS was associated with a decreased dimension of the aortic root and the ascending aorta.

CONCLUSION

Patients with AS and ascending aortic dilatation almost exclusively have a BAV. An increasing severity of valve pathology was related to decreasing dimensions of the aortic root and the ascending aorta, and the pattern was strikingly similar in TAV and BAV patients. The high frequency of ascending aortic dilatations in BAV patients cannot be explained by the valve pathology.

Release of leukotriene B4, transforming growth factor-beta1 and microparticles in relation to aortic valve calcification

BACKGROUND AND AIM OF THE STUDY

Aortic stenosis, the most frequent valvulopathy in the Western world, is characterized by an important extracellular matrix (ECM) remodeling and a process of calcification in the aortic valves. One physiopathological assumption is that transforming growth factor-beta1 (TGF-beta1) acts through ECM remodeling and plays a role in calcification, implicating also microparticles (MPs). Another recent notion is the active involvement of inflammatory mediators in the calcification process of aortic stenosis.

METHODS

A total of 105 aortic valves was collected from patients suffering from calcified aortic stenosis with either tricuspid valve (AS) or bicuspid aortic valve (BAV), rheumatic aortic stenosis (RA), endocarditis, or aortic regurgitation (AR). Each valve was incubated for 24 h in culture medium and the supernatants (conditioned media) were used to measure the concentrations of leukotriene B4 (LTB4) and TGF-beta1 and to quantify the number of MPs released. Valvular calcification was evaluated using biphotonic absorptiometry.

RESULTS

LTB4 concentrations were significantly higher in media conditioned by AS valves compared to those conditioned by RA and endocarditis valves. In addition, LTB4 concentrations correlated significantly with the calcium content of the aortic valves. In contrast, the concentrations of TGF-beta1 and MPs in the conditioned media did not differ significantly between the various groups of valves, and there was no significant correlation between calcification and either TGF-beta1 or the number of MPs released from the aortic valves.

CONCLUSION

Taken together, these results indicate that inflammatory signaling through LTB4 may be more closely linked to calcification and aortic stenosis than signaling through TGF-beta1 and MPs.

Echocardiography in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has become a feasible and effective therapeutic option for patients with severe aortic stenosis and high operative risk or relative contraindications for surgical aortic valve replacement (SAVR). Patient selection plays a crucial role in the success of TAVI. Echocardiography is a mainstay during the whole process starting with the very important morphological evaluation and accurate measurement of the aortic root, followed by guiding the procedure and detecting possible complications, and ending with serial assessment of the patient's heart and the implanted prosthesis. This present article reviews the role of echocardiography before, during, and after transcatheter aortic valve implantation.

Aortic valve leaflet glycosaminoglycans composition and modification in severe chronic valve regurgitation

BACKGROUND AND AIM OF THE STUDY

The surgical segments of aortic valve leaflets from patients with severe chronic aortic regurgitation were analyzed (by percentage and structure) for their content of complex polysaccharides and glycosaminoglycans (GAGs), and compared with control segments.

METHODS

The GAG, hyaluronic acid (HA), chondroitin sulfate (CS) and dermatan sulfate (DS) and disaccharide contents were determined in segments (leaflet, root attachment region and belly) of aortic valve leaflets (non-coronary, left coronary and right coronary) using a multi-analytical approach.

RESULTS

The aortic valve leaflets showed the presence of HA and CS/DS, with an overall charge density of -0.51-0.55. The CS/DS polymers showed a 4-sulfated/6-sulfated ratio of -0.70-0.77 in the belly, and -1.60-1.72 in commissure parts (-/+124%). The total amount of GAGs was -1.60-2.40 microg/mg of tissue. A significant increase in sulfated GAGs was observed in all valve parts in patients suffering from severe aortic insufficiency, as well as an increase in the 4-sulfated/6-sulfated ratio in the leaflet belly (-/+102%).

CONCLUSION

It is speculated that differences in 4-sulfated/6-sulfated ratio determined in the belly and leaflet attachment region-commissure parts of the leaflets may correlate with the tensile or compressive loading of normal aortic valve regions. At the same time, it may be assumed that the increase in sulfated GAGs and 4-sulfated/6-sulfated ratio in the leaflet belly of valves taken from patients suffering severe aortic insufficiency was consistent with an altered matrix microstructure capable of influencing the hydration of these pathological tissues, and of conditioning their mechanical weakness.

[Experience of application of aortal mechanical and biological valves]

Immediate results of implantation of mechanical and biological prosthesis of aortal valve in men and women, aged 60-75 yrs old, were analyzed. Improvement was noted in all the patients, not depending on the implanted valve kind and the concurrent diseases present. There was noted, that while presence of general tendency for improvement, in the women the trustworthy enhancing of the output fraction was absent.

Development of a consensus document to improve multireader concordance and accuracy of aortic regurgitation severity grading by echocardiography versus cardiac magnetic resonance imaging

Current guidelines recommend a multiparametric echocardiographic assessment of aortic regurgitation (AR). However, the absence of a hierarchical weighting of discordant parameters could cause interobserver variability. In the present study, we sought to define and improve the interobserver variability of AR assessment. Seventeen level 3 readers graded 20 randomly selected patients with AR. The readers also provided a usefulness score for each parameter, depending on its influence on their decision of the AR severity grade. A consensus strategy was subsequently formulated and validated against cardiac magnetic resonance imaging in a separate group of 80 patients. The readers were updated with the consensus document and recalibrated using the same cases. Agreement was statistically assessed using Randolph's free-marginal multirater kappa. At baseline, no uniform approach was used to combine the individual parameters, contributing to the interobserver variability (overall kappa 0.5). A consensus strategy to categorize AR severity was developed in which the left ventricular volume took precedence over the other parameters and was used to differentiate chronic severe AR from less severe categories. Recalibration of the readers using this consensus strategy improved concordance (kappa increased to 0.7). The new strategy also improved the accuracy relative to cardiac magnetic resonance imaging, as evidenced by full agreement on severe AR between the consensus document-based grading and AR severity defined by cardiac magnetic resonance imaging in the separate validation group of 80 patients. In conclusion, grading of chronic AR using a multiparametric approach has suboptimal consistency between readers and a left ventricular volume-based consensus document improved concordance and accuracy.

A rare cause of acute heart failure

We describe a rare clinical case of ruptured sinus of Valsalva aneurysm (RSVA) into the right ventricle, complicated with severe aortic regurgitation (AR) and myocardial ischaemia. The AR was caused by a hemodynamic effect solely, in which the shunt of blood flow through the ruptured site pulled the right aortic cusp away from closure. The pathological mechanism of the AR was clearly visualized by transesophageal echocardiography. Early successful primary closure of the RSVA resulted in resolution of the associated AR without any additional procedure.

Psychic trauma as cause of death

AIM

of study Psychic trauma is described as the action of 'an emotionally overwhelming factor' capable of causing neurovegetative alterations leading to transitory or persisting bodily changes. The medico-legal concept of psychic trauma and its definition as a cause in penal cases is debated. The authors present three cases of death after psychic trauma, and discuss the definition of cause within the penal ambit of identified 'emotionally overwhelming factors'.

MATERIALS AND METHODS

The methodological approach to ascertainment and criterion-based assessment in each case involved the following phases: (1) examination of circumstantial evidence, clinical records and documentation; (2) autopsy; (3) ascertainment of cause of death; and (4) ascertainment of psychic trauma, and its coexisting relationship with the cause of death.

RESULTS

The results and assessment of each of the three cases are discussed from the viewpoint of the causal connotation of psychic trauma. In the cases presented, psychic trauma caused death, as deduced from assessment of the type of externally caused emotional insult, the subjects' personal characteristics and the circumstances of the event causing death.

CONCLUSIONS

In cases of death due to psychic trauma, careful methodological ascertainment is essential, with the double aim of defining 'emotionally overwhelming factors' as a significant cause of death from the penal point of view, and of identifying the responsibility of third parties involved in the death event and associated dynamics of homicide.

Epidural analgesia and vaginal delivery in a patient with aortic stenosis and insufficiency

OBJECTIVE

To report a successful vaginal delivery using slow infusion of epidural analgesia in a patient with both severe aortic stenosis and insufficiency.

CLINICAL PRESENTATION AND INTERVENTION

A 26-year-old primigravid patient presented to our hospital for delivery. She had aortic stenosis and insufficiency due to rheumatic fever. Although the obstetrician recommended cesarean section owing to her cardiac status, she insisted upon vaginal delivery. We performed low-dose epidural analgesia with 10 ml of 0.125% ropivacaine and 20 μg fentanyl. She had spontaneous vaginal delivery without complication.

CONCLUSION

This case showed that in spite of the cardiac pathology, vaginal delivery under low-dose slow infusion of epidural analgesia was successful and therefore may be a safe alternative to cesarean section for cardiac patients.

Associations between exercise-induced pulmonary haemorrhage, right ventricular dimensions and atrioventricular valve regurgitation in conditioned National Hunt racehorses

REASONS FOR PERFORMING STUDY

Exercise-induced pulmonary haemorrhage (EIPH) and tricuspid (TR) and mitral valve regurgitation (MR) are conditions with high prevalence in conditioned Thoroughbreds. Stress failure of pulmonary capillaries, leading to EIPH, is most likely when pulmonary vascular pressure is increased, and mitral regurgitation can result in pulmonary venous hypertension.

HYPOTHESIS

There might be an association between MR and EIPH and the right ventricle (RV) of horses known to suffer repeated episodes of EIPH, as their hearts would be subject to higher pulmonary vascular pressures and cardiac output during training and hence increased RV afterload and preload.

METHODS

An echocardiographic and auscultation study was conducted in 121 race-fit National Hunt Thoroughbreds. Cardiac auscultation and echocardiography were performed. A guided M-mode image of the RV just below the tricuspid valve was obtained from a right parasternal location and colour flow Doppler (CFD) used to interrogate the tricuspid valve and right atrium. The mitral valve was similarly examined from the left hemithorax. Severity of TR and MR by CFD was graded. Binary data on EIPH, based on whether the horse was perceived to have a clinically significant problem with EIPH, were determined retrospectively for each horse by the horses' primary care veterinary surgeon from medical and other records. Data were analysed using a standard logistic regression analysis approach.

RESULTS

EIPH was significantly and positively associated with the systolic and diastolic dimensions of the RV (P = 0.017 and 0.011 respectively) and this association was not sensitive to the effects of age or weight. There were no significant associations between EIPH and TR or MR by auscultation or CFD (TR: auscultation P = 0.1; CFD P = 0.2 and MR: auscultation P = 0.07; CFD P = 0.37).

CONCLUSIONS AND CLINICAL RELEVANCE

This study was limited by the method used to classify EIPH, but there was no association between EIPH and horse age, weight, TR or MR in this population of Thoroughbreds. Nevertheless, RV internal dimension was greater in horses obviously affected by EIPH, suggesting that factors resulting in EIPH may directly or indirectly affect RV remodelling in athletic horses.

Quantification of left ventricular remodeling in response to isolated aortic or mitral regurgitation

BACKGROUND

The treatment of patients with aortic regurgitation (AR) or mitral regurgitation (MR) relies on the accurate assessment of the severity of the regurgitation as well as its effect on left ventricular (LV) size and function. Cardiovascular Magnetic Resonance (CMR) is an excellent tool for quantifying regurgitant volumes as well as LV size and function. The 2008 AHA/ACC management guidelines for the therapy of patients with AR or MR only describe LV size in terms of linear dimensions (i.e. end-diastolic and end-systolic dimension). LV volumes that correspond to these linear dimensions have not been published in the peer-reviewed literature. The purpose of this study is to determine the effect of regurgitant volume on LV volumes and chamber dimensions in patients with isolated AR or MR and preserved LV function.

METHODS

Regurgitant volume, LV volume, mass, linear dimensions, and ejection fraction, were determined in 34 consecutive patients with isolated AR and 23 consecutive patients with MR and no other known cardiac disease.

RESULTS

There is a strong, linear relationship between regurgitant volume and LV end-diastolic volume index (aortic regurgitation r2 = 0.8, mitral regurgitation r2 = 0.8). Bland-Altman analysis of regurgitant volume shows little interobserver variation (AR: 0.6 +/- 4 ml; MR 4 +/- 6 ml). The correlation is much poorer between regurgitant volume and commonly used clinical linear measures such as end-systolic dimension (mitral regurgitation r2 = 0.3, aortic regurgitation r2 = 0.5). For a given regurgitant volume, AR causes greater LV enlargement and hypertrophy than MR.

CONCLUSION

CMR is an accurate and robust technique for quantifying regurgitant volume in patients with AR or MR. Ventricular volumes show a stronger correlation with regurgitant volume than linear dimensions, suggesting LV volumes better reflect ventricular remodeling in patients with isolated mitral or aortic regurgitation. Ventricular volumes that correspond to published recommended linear dimensions are determined to guide the timing of surgical intervention.

Computational analysis of an aortic valve jet with Lagrangian coherent structures

Important progress has been achieved in recent years in simulating the fluid-structure interaction around cardiac valves. An important step in making these computational tools useful to clinical practice is the development of postprocessing techniques to extract clinically relevant information from these simulations. This work focuses on flow through the aortic valve and illustrates how the computation of Lagrangian coherent structures can be used to improve insight into the transport mechanics of the flow downstream of the valve, toward the goal of aiding clinical decision making and the understanding of pathophysiology.

[Myocarditis and fibroplastic endocarditis in Wegener's granulomatosis]

The paper describes an autopsy case of Wegener's granulomatosis with a rare variant of a cardiac lesion--the concurrence of aortic valvular disease (aortic regurgitation), fibroplastic endocarditis, and complete transverse blockade, followed by pacemaker implantation. The direct cause of death in the female patient was multiple organ dysfunction: progressive chronic heart failure, adult respiratory distress syndrome, acute hepatorenal failure, and pancreonecrosis. The data available in the Russian and foreign literature on investigations dealing with cardiac pathology in patients with Wegener's granulomatosis are analyzed.

[The possibility to predict results of aortic valve prosthetics from initial anatomic and functional properties]

The study included 394 patients selected for aortic valve prosthetics. Group 1 comprised patients with prevailing aortic stenosis (n = 165 or 41.9%), group 2 patients with prevailing aortic insufficiency (n = 229 or 58.1%). Their preoperative characteristics were arbitrary categorized as follows: circulatory disturbances (F1), anthropometric parameters (F2), central hemodynamic parameters (F3), anatomofuntional parameters (F4), left ventricular myocardium parameters (F5), valvular morphology (F6), valvular parameters (F7). Correlation analysis was used to predict surgery outcome. Excel 2000-based software was created to assess the probability of favourable outcome.

Quantification of chronic aortic regurgitation by vector flow mapping: a novel echocardiographic method

AIMS

Quantification of aortic regurgitation (AR) using echocardiography is challenging. A newly established echocardiographic method, vector flow mapping (VFM), can directly measure blood flow volume (FV) regardless of rheological characteristics. We intended to assess the accuracy of VFM in the quantification of chronic AR.

METHODS AND RESULTS

Twenty-one patients with chronic AR, along with 21 healthy volunteers selected as controls, underwent conventional echocardiography and estimation of aortic blood flow using quantitative Doppler and VFM. The regurgitation ratio (RegR), derived as the quotient of backward and forward aortic FV in the ascending aorta measured by VFM, increased with AR severity: 1.1 +/- 1.5% (normal), 11.4 +/- 3.8% (mild AR), 31.2 +/- 8.0% (moderate AR), and 59.3 +/- 4.7% (severe AR). In a linear regression model, RegR closely correlated with the VC width (r = 0.932) and regurgitation fraction and effective regurgitant orifice measured by the quantitative Doppler method (r = 0.929 and 0.891, respectively). The intra- and interobserver variability of RegR was 4.2 and 6.7%, respectively. There was no difference between RegR measured in the apical five-chamber view and in that in apical three-chamber view using the paired t-test (P = 0.751).

CONCLUSION

RegR measured by VFM, a new Doppler method allowing quantitative analysis of FV in spite of the presence of turbulent flow, is a highly reproducible parameter with good accuracy for AR quantification.

Development of mature lamellar bone with a hematopoietic compartment in an aortic valve homograft

Two foci of mature lamellar bone with features of remodeling and with an adjacent hematopoietic compartment were revealed for the first time in an aortic valve homograft by hematoxylin and eosin staining and polarized light microscopy. The valve had been obtained originally from a 52-year-old non-beating-heart donor and implanted as 'fresh antibiotic-preserved' into the left ventricular outflow tract of a 21-year-old man, but was explanted after six years due to valvular insufficiency. The areas close to bone showed the presence of cells resembling osteoblasts, osteoclasts and degenerating chondrocytes. Von Kossa staining disclosed a small area of dystrophic calcification in the vicinity of one bone fragment, whereas the second fragment was accompanied by only weak, diffuse calcification. These findings shows that the formation of ectopic mature bone with secondary development of the hematopoietic compartment can occur in a relatively short time, and suggest that initiators of the process may be present in the grafted valve.

An atypical cause of aortic valve prolapse

We encountered a surgical case of aortic valve prolapse caused by a fissure formed in the commissural region and coronary cusp, and we achieved a favorable outcome. On pathologic examination, the fissured valve was found to be myxoid degeneration with ruptured elastic fibers and clustering of foamy macrophages, and it was diagnosed as an atherosclerotic change not associated with rheumatic change. The fissure appeared to develop because of hypertensive stress in a region rendered vulnerable by atherosclerosis. Although this mechanism is atypical, it should be recognized that poorly controlled hypertension can cause aortic valve prolapse and induce acute heart failure.

Aortic valve replacement for Libman-Sacks endocarditis

Cardiac involvement is a recognized complication of systemic lupus erythematosus (SLE), which can involve most cardiac components, including pericardium, conduction system, myocardium, heart valves, and coronaries. Libman-Sacks (verrucous) endocarditis is the characteristic cardiac valvular manifestation. We report a patient with SLE who had severe aortic regurgitation caused by Libman-Sacks endocarditis. The patient underwent successful mechanical aortic valve replacement.

Cardiovascular magnetic resonance of quinticuspid aortic valve with aortic regurgitation and dilated ascending aorta

We report a rare case of a quinticuspid aortic valve associated with regurgitation and dilation of the ascending aorta, which was diagnosed and post-surgically followed up by cardiovascular magnetic resonance and dual source computed tomography.

Biventricular adaptation to volume overload in mice with aortic regurgitation

BACKGROUND

Aortic valve regurgitation is usually caused by impaired coaptation of the aortic valve cusps during diastole. Hypercholesterolemia produces aortic valve lipid deposition, fibrosis, and calcification in both mice and humans, which could impair coaptation of cusps. However, a link between hypercholesterolemia and aortic regurgitation has not been established in either species. The purpose of this study was to ascertain the prevalence of aortic regurgitation in hypercholesterolemic mice and to determine its impact on the left and right ventricles.

METHODS AND RESULTS

Eighty Ldlr-/-/Apob100/100/Mttpfl/fl/Mx1Cre+/+ ("Reversa") hypercholesterolemic mice and 40 control mice were screened for aortic regurgitation (AR) with magnetic resonance imaging at age 7.5 months. The prevalence of AR was 40% in Reversa mice, with moderate or severe regurgitation (AR+) in 19% of mice. In control mice, AR prevalence was 13% (p = 0.004 vs. Reversa), and was invariably trace or mild in severity. In-depth evaluation of cardiac response to volume overload was performed in 12 AR-positive and 12 AR-negative Reversa mice. Regurgitant fraction was 0.34 +/- 0.04 in AR-positive vs. 0.02 +/- 0.01 in AR-negative (mean +/- SE; p < 0.001). AR-positive mice had significantly increased left ventricular end-diastolic volume and mass and reduced ejection fraction in both ventricles. When left ventricular ejection fraction fell below 0.60 in AR-positive (n = 7) mice, remodeling occurred and right ventricular systolic function progressively worsened.

CONCLUSION

Hypercholesterolemia causes aortic valve regurgitation with moderate prevalence in mice. When present, aortic valve regurgitation causes volume overload and pathological remodeling of both ventricles.