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How to cite: Silbiger J. J. (2014). Does left atrial enlargement contribute to mitral leaflet tethering in patients with functional mitral regurgitation? Proposed role of atriogenic leaflet tethering. The Journal of heart valve disease, 23(3), 385–386.

Background and aim of the study: Remodeling of the pulmonary autograft upon exposure to systemic pressure can lead to progressive dilatation and aneurysmal pathology. Remodeling is driven by changes in autograft wall stress upon exposure to systemic pressure; however, the magnitude of these changes is unknown. Previously, a porcine autograft finite element model was developed to determine wall stress, but the porcine and human material properties differed significantly. Hence, the study aim was to understand human pulmonary autograft biomechanics that lead to remodeling by determining wall stress magnitudes immediately after the Ross procedure using finite element analysis (FEA).

Methods: Human pulmonary root was scanned by high-resolution microcomputed tomography to construct a realistic three-dimensional geometric mesh. Stress-strain data from biaxial stretch testing was incorporated into an Ogden hyperelastic model to describe autograft mechanical properties for an adult Ross patient. Autograft dilatation and wall stress distribution during pulmonic and systemic pressures prior to remodeling were determined using explicit FEA in LS-DYNA.

Results: Human pulmonary autograft demonstrated non-linear material properties, being highly compliant in the low-strain region, and stiffening at high strain. The majority of dilatation occurred with < 20 mmHg pressurization. From pulmonary to systemic pressures, the increases in autograft diameter were up to 17%. Likewise, the maximal wall stress increased approximately 14.6-fold compared to diastolic pressures (from 13.0 to 190.1kPa), and six-fold compared to systolic pressures (from 48.6 to 289.6kPa).

Conclusion: The first finite element model of the human pulmonary autograft was developed and used to demonstrate how autograft material properties prevent significant dilatation upon initial exposure to systemic pressure. Mild dilatation was noted in the sinuses and sinotubular junction. Autograft wall stress was increased greatly when subjected to systemic pressures, and may trigger biomechanical remodeling of the autograft. Sustained exposure to higher wall stresses, coupled with inadequate remodeling, may lead to future autograft dilatation.

How to cite: Wisneski, A. D., Matthews, P. B., Azadani, A. N., Mookhoek, A., Chitsaz, S., Guccione, J. M., Ge, L., & Tseng, E. E. (2014). Human pulmonary autograft wall stress at systemic pressures prior to remodeling after the Ross procedure. The Journal of heart valve disease, 23(3), 377–384.

Background and aim of the study: Tricuspid valve exploration during surgery plays an important role in the decision-making of concomitant tricuspid annuloplasty at the time of left-sided valve surgery. However, at present a good standard to define tricuspid annular dilatation is not available. The study aim was to introduce an alternative method based on annular circumference to judge the extent of annular dilatation, and investigate its predictive ability for the postoperative progression of tricuspid regurgitation (TR).

Methods: A total of 127 patients with non-significant TR who underwent isolated left-sided valve surgery at the authors' institution between October 2010 and October 2011 were enrolled prospectively in the study. Intraoperative measurements of the tricuspid annular circumference (TAC) were made for each patient and adjusted to the patient's body surface area to give the TAC index (TACI). The primary end-point was defined as the progression of TR by more than two grades, or a final TR grade > or = 3+ at follow up echocardiography.

Results: The mean follow up period was 30.2 months (range: 24-37 months). Three variables were found to be associated with postoperative TR progression, including atrial fibrillation, left atrial diameter, and the intraoperatively measured TACI (p = -0.1 in univariate analysis). However, on multiple regression analysis only the TACI (OR 1.586; 95% CI 1.303-1.929; p < 0.001) was significantly associated with TR progression. Based on the receiver-operator characteristic curve, it was possible to derive an optimal cut-off value (83 mm/m2) to predict the postoperative development of TR with higher sensitivity and specificity.

Conclusion: Among a patient population with predominantly rheumatic left-sided valve disease, the tricuspid annular circumference, when assessed with special sizers, proved to be an ideal method to judge if the annulus would dilate, or not, during surgery. A deduced TACI threshold of 83 mm/m2 was recommended as an indication for prophylactic tricuspid repair.

How to cite: Zhu, T. Y., Meng, X., Han, J., Li, Y., & Ma, N. (2014). An alternative intraoperative method based on annular circumference for the decision-making of prophylactic tricuspid annuloplasty. The Journal of heart valve disease, 23(3), 370–376.

Background and aim of the study: The results were evaluated of a non-resective technique for mitral valve repair with artificial chordae implantation that allows modification of the length of the chordae as many times as necessary, and avoids inadvertent alteration of chordal length during fixation by using removable clips.

Methods: After having determined the length of the artificial chordae, a removable clip was tied on the two thread ends to prevent sliding when performing the competence test. The length of the artificial chordae could be modified by opening the clip and closing it elsewhere along the chordae length. When the competence test was satisfactory, the threads were knotted on the clips. Long-term follow up was completed between January and May 2012, by echocardiography plus consultation with a cardiologist at the authors' institution.

Results: A total of 47 patients underwent repair with this technique. Follow up was complete at a median of 6.0 years. There were no in-hospital deaths, but four deaths occurred during the follow up period (8.5%). The survival rate at six years was 91.5 +/- 2.1%. One patient (2.1%) had recurrent mitral regurgitation (MR) and required reoperation within two years after the initial surgery. The event-free survival rate, defined as survival free from death, reoperation or cardiovascular adverse events, was 87.2 +/- 5.2% at six years. At the time of follow up, echocardiography identified a fully competent valve or minimal MR in 45 patients (96%), mild MR in one patient (2.1%), and significant MR in one patient (2.1%).

Conclusion: A satisfactory six-year outcome is reported for this method, whereby removable clips were used to determine the correct length of the artificial chordae, and for accurate tying of the knots.

How to cite: Chopard, R., Perrotti, A., Durst, C., Meneveau, N., Stoica, L. L., & Chocron, S. (2014). Six-year outcomes after non-resective mitral valve repair with artificial chordae using removable clips. The Journal of heart valve disease, 23(3), 364–369.

The case is reported of a 38-year-old male patient with pulmonary homograft acute infective endocarditis and aortic root dilation that occurred 13 years after a Ross procedure for bicuspid aortic valve regurgitation. Aortic and pulmonary root replacements were performed, using a Freestyle stentless aortic root bioprosthesis in both cases, with excellent hemodynamics on postoperative echocardiography. In addition, preoperative systemic septic embolization had occurred despite an absence of left-sided endocarditis, presumably due to an intrapulmonary shunt. This case report demonstrates the feasibility of a double stentless bioprosthesis approach, and stresses the need to remain vigilant for septic embolization even in isolated right-sided endocarditis.

How to cite: Smeets, C. J., Bertrand, P. B., Spadaccio, C., Beran, M., Verhaert, D., Vandervoort, P. M., Gutermann, H., & Dion, R. A. (2014). Pulmonary homograft endocarditis and aortic autograft failure after Ross procedure: a double stentless bioprosthesis approach. The Journal of heart valve disease, 23(3), 360–363.

Background and aim of the study: Mitral valve reconstruction (MVP) is currently the standard treatment for degenerative mitral regurgitation (MR). However, when MR is due to infective endocarditis (IE) the range of pathophysiology present often makes any repair challenging. Hence, the authors' clinical experience of MVP to treat MR caused by IE was analyzed.

Methods: Between September 2004 and March 2011, a total of 26 patients (20 males, six females) who had been diagnosed with MR due to IE (single surgeon, retrospective review) were operated on. Among the 26 patients (17 active, nine healed; six Carpentier type I, 20 Carpentier type II), MVP was performed in 11 patients (42.3%), of which six were active cases and five were healed. All MVP procedures included ring annuloplasty. A variety of repair techniques was used, including triangular resection (n = 3), pericardial patch reconstruction (n = 4), commissuroplasty (n = 4), artificial chordoplasty (n = 1), chordae transfer (n = 2), and secondary chordae resection (n = 1). Six of 17 patients who had a pathology favorable for repair underwent valve replacement; the etiologies were underlying valvular disease (n = 2, rheumatic pathology), Child's group C liver cirrhosis (n = 1), second redo sternotomy (n = 1), multivalvular disease (n = 1), and critical medical condition (n = 1, septic shock).

Results: The mean follow up duration was 35.7 months (range: 0.1-84.9 months). Among the repair group, none of the patients showed residual MR on postoperative echocardiography. There were no early or late deaths, and no patient showed newly developed MR during the follow up. Among the replacement group, three patients died of noncardiac causes during the follow up (two early deaths and one late death).

Conclusion: MVP for MR due to IE showed successful clinical outcomes. Valve replacement was performed in some patients with a repair-favorable pathology, after taking into consideration any comorbidities. Whilst standard repair techniques were sufficient, careful decision-making was the key to achieving excellent results for MVP.

How to cite: Chang, H. W., Kim, K. H., Hwang, H. Y., & Kim, J. S. (2014). Role of mitral valve repair in infective endocarditis. The Journal of heart valve disease, 23(3), 350–359.

Background and aim of the study: While concomitant medical and surgical therapy has improved the treatment of infective endocarditis (IE), mortality and postoperative complications remain high. A minimally invasive approach to mitral valve surgery has been associated with decreased morbidity and mortality in high-risk populations. The study aim was to analyze the feasibility of a minimally invasive approach to valve surgery for native mitral valve IE.

Methods: All heart operations performed between January 2008 and April 2013 at the authors' institution were reviewed retrospectively. The operative times, intensive care unit (ICU) and hospital lengths of stay, postoperative complications, and in-hospital mortality of patients who underwent minimally invasive surgery via a right anterior minithoracotomy for native mitral valve IE were compared to those of a cohort which underwent median sternotomy. A Kaplan-Meier analysis was performed to compare long-term survival between the cohorts.

Results: A total of 50 patients was identified (22 minithoracotomy, 28 median sternotomy). The baseline characteristics, mitral valve pathology and disease burden (annular abscess, cusp perforation, vegetation size, chordal rupture) were similar between the groups. There was no difference in the rate of active versus healed disease. Patients who underwent a minithoracotomy had fewer postoperative composite complications (41% versus 75%, p = 0.02), mainly driven by a decreased incidence of sepsis (0% versus 21%, p = 0.02), as well as less use of intraoperative blood products (59% versus 93%, p = 0.004), higher rates of mitral valve repair (55% versus 25%, p = 0.03), and a shorter ICU length of stay (56 versus 114 h, p = 0.009). Repair of the mitral valve was associated with a decreased risk of postoperative composite complications (OR 0.16, 95% CI 0.04-0.71, p = 0.02). At 2.5 years postoperatively, survival was estimated at 80% and 68% in the minithoracotomy and median sternotomy groups, respectively (p = 0.33).

Conclusion: A right anterior minithoracotomy approach for native mitral valve IE provides a safe and feasible alternative to conventional median sternotomy surgery, with improved outcomes conferred by valve repair compared to replacement.

How to cite: Mihos, C. G., Santana, O., Pineda, A. M., Lamas, G. A., & Lamelas, J. (2014). Right anterior minithoracotomy versus median sternotomy surgery for native mitral valve infective endocarditis. The Journal of heart valve disease, 23(3), 343–349.

Background and aim of the study: The authors' institution participated in a 28-center FDA Investigational Device Exemption study to evaluate the Sorin Mitroflow pericardial aortic bioprosthesis. Six high-enrolling sites evaluated patients on an annual basis as part of an ongoing hemodynamic study. These data represent patients followed for an average of five years after implant, with annual echocardiography.

Methods: Seventy-one patients were entered into the study and constitute the basis of this review. Mean follow up was 3.3 +/- 2.0 years (range: 0-5.5 years), with a cumulative follow up of 233 patient-years. The mean patient age was 73.8 years (range: 45-89 years), and 52% were males. The majority of aortic valve lesions were stenosis (63%) or mixed (30%), and nine patients (12.7%) were reoperations. Sixty-one patients (86%) had concomitant procedures, the most common being coronary artery bypass grafting (70%).

Results: A total of 281 echocardiograms was obtained from the patients over a five-year period. The largest number of echocardiograms was obtained with 23-mm valve implants (n = 122), followed by 25 mm valve implants (n = 87). The early baseline (30-day) mean gradient was < or = 10 mm in all patients. The mean gradient decreased as the valve size increased (21 mm valve gradient = 10.0 +/- 5.6 mmHg; 27 mm valve gradient = 6.2 +/- 2.2 mmHg). The mean increase in gradient at five years was < 7 mmHg, with a trend towards increased gradients at smaller valve sizes. The effective orifice area (EOA) showed a trend to decline slightly with 21 mm valves (from 1.5 to 1.2 cm2) and 23 mm valves (1.4 to 1.2 cm2), but there was either no change or a slight increase in larger-size valves. Left ventricular mass regression occurred mainly within the first year (18.9%), but then remained stable throughout the study period. No greater than mild prosthetic aortic valve regurgitation was observed over the study period.

Conclusion: The Sorin Mitroflow aortic valve provides excellent hemodynamic results up to five years, with minimal increase in mean gradients, acceptable peak gradients, and good EOAs with all valves sizes.

How to cite: Heimansohn, D. A., Robison, R. J., Walts, P., Salerno, C. T., & Dolman, B. (2014). A single-center experience with the Sorin Mitroflow pericardial aortic valve: hemodynamics up to five years. The Journal of heart valve disease, 23(3), 338–342.

Background and aim of the study: Although the pulmonary position has been preferred for the placement of homografts or bioprosthetic valves, the limited longevity of these implants makes reoperation almost unavoidable. Good durability of mechanical valves in the pulmonary position has been reported. The mid-term outcomes were analyzed of patients who received an On-X mechanical heart valve for pulmonary valve replacement (PVR) with a relatively low International Normalized Ratio (INR).

Methods: Between February 2008 and February 2011, mechanical On-X valves (size range: 19 to 25 mm) were implanted for PVR in six patients. Tetralogy of Fallot (ToF) was the most common diagnosis (n = 6). Postoperatively, warfarin was used to maintain the INR at 1.5-2.0. The surgical results and follow up were reviewed retrospectively, with valve failure, thrombosis, embolism, bleeding, reoperation and death being defined as end-points.

Results: There was no intraoperative or in-hospital mortality. The mean age of patients at the time of PVR was 31 +/- 19.7 years (range: 16-61 years). In patients who underwent repair of ToF (n = 4) the average duration between PVR and previous right ventricular outflow tract (RVOT) reconstruction was 8.75 +/- 3.3 years (range: 5-12 years). The mean follow up period was 3.13 +/- 1.31 years (range: 2-5 years). There was no 30-day mortality, late death, thromboembolism, major bleeding event or valve dysfunction, and no patient needed reoperation. All survivors were categorized as NYHA class I or II.

Conclusion: A three-year experience with the On-X bileaflet mechanical valve in the pulmonary position demonstrated excellent mid-term durability, with no thromboembolisms or bleeding events when the INR was maintained at 1.5-2.0. For patients who require PVR, either as primary procedure or reoperation, the On-X mechanical heart valve might represent an appropriate option.

How to cite: Yang, C. C., Wei, H. J., Hsieh, S. R., Wang, C. C., Yu, C. L., Lin, Y. K., Tsai, C. L., & Chang, Y. (2014). Excellent mid-term durability of the On-X mechanical aortic valve in the pulmonary position with a low international normalized ratio. The Journal of heart valve disease, 23(3), 333–337.

Background and aim of the study: The study aim was to compare early postoperative hemodynamic gradients after supra-annular implantation of the Trifecta and Perimount Magna Ease aortic bioprostheses.

Methods: Between January 2010 and December 2011, a total of 235 patients (105 males, 130 females; mean age at surgery 73.8 +/- 10.2 years) underwent supra-annular aortic valve replacement (AVR), with or without concomitant procedures. The patients were divided into 2 groups receiving either the Perimount Magna Ease (n = 117) or Trifecta (n = 118). Concomitant procedures were performed in 133 patients (56.6%), and 25 procedures (10.6%) were redos. Patients with postoperative severe left ventricular dysfunction and moderate to severe mitral regurgitation were excluded. Gradients were calculated pre-discharge using transthoracic echocardiography. Effective orifice area calculations were not performed. Data were collected retrospectively from hospital databases and analyzed using SPSS 17.

Results: Both groups compared well for 14 variables. Group A had a higher number of redo operations and the patients were younger. Postoperative peak and mean gradients (in mmHg) for the Magna Ease group versus Trifecta group were: 19 mm valves, 33.5 +/- 16 versus 24.7 +/- 10 (p = 0.11) and 17.4 +/- 6.5 versus 12.7 +/- 4.4 (p = 0.05); 21 mm, 27.2 +/- 9.1 versus 21.8 +/- 7.2 (p = 0.001) and 13.8 +/- 4.7 versus 10.7 +/- 3.4 (p = 0.001); 23 mm, 25.6 +/- 7.8 versus 20.1 +/- 7.9 (p = 0.005) and 13 +/- 4 versus 10.1 +/- 4.3 (p = 0.002); 25 mm, 22.3 +/- 7.8 versus 15.6 +/- 5.1 (p = 0.01) and 12.8 +/- 4.1 versus 8 +/- 2.8 (p = 0.02). The overall mortality was 3.4%. The median hospital stay was nine days in both groups (p = 0.13). Mortality (p = 0.5), and incidences of perioperative stroke (p = 0.45), postoperative new-onset atrial fibrillation (p = 0.26) and permanent pacemaker implantation (p = 0.8) were similar in both groups.

Conclusion: Early postoperative gradients were significantly lower in patients receiving Trifecta valves, although the long-term clinical outcome and durability of the valve will require further evaluation.

How to cite: Modi, A., Pousios, D., Sadeque, S., Velissaris, T., Barlow, C., Livesey, S., Tsang, G. M., & Ohri, S. K. (2014). Early in-vivo hemodynamic comparison of supra-annular aortic bioprostheses: Trifecta versus Perimount Magna Ease. The Journal of heart valve disease, 23(3), 325–332.

Background and aim of the study: Minimally invasive techniques for aortic valve replacement (AVR) have been developed as an alternative to conventional AVR for patients with high operative risk. Yet, these techniques are still associated with an increased risk of postoperative conduction disorders. The study aim was to identify the incidence and fate of postoperative conduction disorders in patients undergoing sutureless (SU) AVR with the Perceval S bioprosthesis.

Methods: In this observational study, patients who underwent SU AVR with the Perceval S prosthesis at the Catharina Hospital, Eindhoven, were analyzed. Electrocardiograms (ECGs) recorded at baseline, within 24 h postoperatively, before hospital discharge and at follow up were collected by reviewing patients' records. The ECGs were analyzed by two independent investigators to record QRS-duration and conduction disorders.

Results: All patients (n = 31) who underwent implantation of the Perceval S bioprosthesis between September 2010 and September 2012 were included. At baseline, three patients (9.7%) had preexisting left bundle branch block (LBBB), and one patient (3.2%) had a permanent pacemaker (PPM). New-onset LBBB developed in 11 patients (39.3%), and was transient in three patients (10.7%). Postoperatively, four patients (13.3%) required PPM implantation because of total atrioventricular block; all of these patients had either pre-existing LBBB (n = 1) or new LBBB (n = 3).

Conclusion: Sutureless AVR with the Perceval S bioprosthesis was frequently complicated by new LBBB, which was persistent in the majority of patients. A relatively high incidence of postoperative PPM implantation was also observed.

How to cite: van Boxtel, A. G., Houthuizen, P., Hamad, M. A., Sjatskig, J., Tan, E., Prinzen, F. W., & van Straten, A. H. (2014). Postoperative conduction disorders after implantation of the self-expandable sutureless Perceval S bioprosthesis. The Journal of heart valve disease, 23(3), 319–324.

Non-invasive aortic valve implantation has become an alternative technique to surgical valve replacement in patients at high risk for open-chest surgery. With over 100,000 procedures already performed clinically, the technology is expected to involve less-critical patients in future. Whereas, biological valve tissue is a fragile material when folded for low-diameter catheter insertion purposes, textile polyester is a less-fragile material and may offer an alternative material to replace valve leaflets. One issue related to textile is the porosity of the material, which may induce exaggerated tissue ingrowth. Today, data relating to interactions between living tissues and fabrics used as valve materials are available only in the mitral position. Hence, the study aim was to observe the interaction pattern when the valve is implanted in the aortic position, and to assess the influence of sinus whirls on this pattern.

How to cite: Heim, F., Gasser, B., Khoffi, F., & Blondel, P. (2014). Textile heart valve: first in-vivo experiment in the aortic position. The Journal of heart valve disease, 23(3), 316–318.

Background and aim of the study: Mitral valve regurgitation (MR) is known to deteriorate following adult atrial septal defect (ASD) repair in the mid to long-term. The study aim was to identify the risk factors for this deterioration.

Methods: Between 1995 and 2011, a total of 93 consecutive patients (aged > or = 18 years) underwent ASD repair at the authors' institution. Patients who underwent concomitant procedures, other than tricuspid annuloplasty or maze procedure, were excluded; hence, 74 patients were enrolled in the study. MR was evaluated by transthoracic echocardiography shortly after surgery and subsequently on a regular basis in the outpatient clinic. Risk factors for the deterioration of MR were estimated using Cox proportional hazards regression.

Results: The mean patient age at surgery was 48.0 +/- 17.1 years, and 20 patients (27%) had atrial fibrillation (AF) preoperatively. The mean follow up was 6.9 +/- 5.5 years. The degree of MR was not unchanged or not improved in 54 patients (73.0%) (group 1), but was increased by one grade in 12 patients (16.2%) (group 2), and by two or more grades in eight patients (10.8%) (group 3). At surgery, all patients in group 3 were aged > 50 years. In group 3, on echocardiography, the average end-diastolic left ventricular dimension was increased from 41.8 mm to 51.8 mm (p = 0.027), and enlargement of the mitral annulus was noted in seven patients. Four of the group 3 patients required reoperation for MR after ASD repair. The Cox proportional hazards model revealed preoperative AF (p = 0.045, hazard ratio (HR): 11.68, 95% confidence interval (95% CI): 1.05-129.48) and Qp/Qs > or = 2.8 (p = 0.015, HR: 9.19, 95% CI :1.53-55.04) to be independent risk factors of new-onset or aggravated MR (by two or more grades) after ASD repair.

Conclusion: An earlier repair of ASD would be preferable in terms of MR aggravated after ASD repair. For elderly patients with a preoperative high Qp/Qs and AF, mitral valve annuloplasty with ASD repair should considered.

How to cite: Yoshida, S., Numata, S., Tsutsumi, Y., Monta, O., Yamazaki, S., Seo, H., Samura, T., & Ohashi, H. (2014). Mitral valve regurgitation after atrial septal defect repair in adults. The Journal of heart valve disease, 23(3), 310–315.

Background and aim of the study: Mitral valve repair to treat mitral regurgitation (MR) in pediatric patients remains challenging because of the complex morphology and fragility of the leaflets. The study aim was to review retrospectively the authors' experience with mitral valve repair using autologous pericardium.

Methods: Between April 2004 and November 2011, nine pediatric patients (six males, three females; mean age 2.4 +/- 4.5 years) underwent mitral valve repair with an autologous fresh (n = 5) or glutaraldehyde-treated pericardium (n = 4) to treat severe MR. The etiology of the MR was acute endocarditis, acute chordal rupture and congenital disease in three, two, and four patients, respectively. Autologous pericardium was used for valvuloplasty, leaflet extension plasty and commissuroplasty in two, five, and two patients, respectively. Artificial chordal replacement was performed in three patients.

Results: No operative deaths or postoperative endocarditis occurred. One patient required mitral valve replacement at three days after the initial mitral repair. The most recent echocardiography findings of the remaining patients after a mean of 6.3 years (range: 1.3-9.0 years) showed that the severity of mitral insufficiency, left ventricular diastolic diameter and fractional shortening were 1.8 +/- 0.6 (grades 0-4), 40.4 +/- 8.4 mm (114.2 +/- 15.8% of normal) and 35.0 +/- 5.0%, respectively.

Conclusion: Mitral valve repair using autologous fresh pericardium is associated with mid-term durability and resistance to infection when used for mitral valve repair of active endocarditis in pediatric patients. Augmentation with autologous pericardium could become an alternative to current surgical options.

How to cite: Takahashi, H., Kadowaki, T., Maruo, A., Yutaka, O., & Oshima, Y. (2014). Mid-term results of mitral valve repair with autologous pericardium in pediatric patients. The Journal of heart valve disease, 23(3), 302–309.

The majority of approaches currently described and practiced in mitral repair surgery result in the vertical immobilization of the posterior leaflet, with the anterior leaflet striving to produce an adequate coaptation. Despite the satisfactory hemodynamic outcome and disappearance of mitral regurgitation, this non-physiological situation results in a redistribution of forces within the mitral apparatus with an increased stress on the leaflets. Biological evidences are pointing at the ability of the valvular interstitial cells to actively respond to biomechanical changes, switching their phenotype and producing different patterns of extracellular matrix proteins. This biological event translates to changes in the anatomical and mechanical properties of the leaflets, leading to an increased stiffening and a susceptibility to develop calcification. These concepts find a clinical reflex in reports on the long-term thickening and calcification of the leaflets after mitral repair, and in the leaflets remodeling phenomena described in chronically dilated ventricles. The importance of respecting the physiological movement and dynamics of the leaflets when performing a valvuloplasty is underlined, and a potential pharmacological modulation of the aforementioned biological processes to ameliorate long-term results of the repair is hypothesized.

How to cite: Spadaccio, C., Gutermann, H., & Dion, R. (2014). Mitral valvuloplasty: when the art of repair meets the biological science. The Journal of heart valve disease, 23(3), 299–301.

Background and aim of the study: The long-term outcomes of aortic valve-sparing (AVS) root replacement in Marfan syndrome (MFS) patients remain uncertain. The study aim was to determine the utilization and outcomes of AVS root replacement in MFS patients enrolled in the Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC). Methods: At the time of this analysis, 788 patients with MFS were enrolled in the GenTAC Registry, of whom 288 had undergone aortic root replacement. Patients who had undergone AVS procedures were compared to those who had undergone aortic valve replacement (AVR). Results: AVS root replacement was performed in 43.5% of MFS patients, and the frequency of AVS was increased over the past five years. AVS patients were younger at the time of surgery (31.0 versus 36.3 years, p = 0.006) and more likely to have had elective rather than emergency surgery compared to AVR patients, in whom aortic valve dysfunction and aortic dissection was the more likely primary indication for surgery. After a mean follow up of 6.2 +/- 3.6 years, none of the 87 AVS patients had required reoperation; in contrast, after a mean follow up of 10.5 +/- 7.6 years, 11.5% of AVR patients required aortic root reoperation. Aortic valve function has been durable, with 95.8% of AVS patients having aortic insufficiency that was graded as mild or less. Conclusion: AVS root replacement is performed commonly among the MFS population, and the durability of the aortic repair and aortic valve function have been excellent to date. These results justify a continued use of the procedure in an elective setting. The GenTAC Registry will be a useful resource to assess the long-term durability of AVS root replacement in the future.

How to cite: Song, H. K., Preiss, L. R., Maslen, C. L., Kroner, B., Devereux, R. B., Roman, M. J., Holmes, K. W., Tolunay, H. E., Desvigne-Nickens, P., Asch, F. M., Milewski, R. K., Bavaria, J., LeMaire, S. A., & GenTAC Consortium (2014). Valve-sparing aortic root replacement in patients with Marfan syndrome enrolled in the National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions. The Journal of heart valve disease, 23(3), 292–298.

The case is presented of a 75-year-old man referred for transcatheter aortic valve implantation. During the procedure the prosthetic aortic valve became dislocated into the left ventricle shortly after expansion. The subsequent steps taken to reposition the valve using only materials at hand are described.

How to cite: Natour, E., Douglas, Y. L., Jainandunsing, J. S., Schurer, R. A., van der Werf, H. W., & van den Heuvel, A. F. (2014). Repositioning of an intraventricular dislocated aortic valve during transcatheter aortic valve implantation. The Journal of heart valve disease, 23(3), 289–291.

Background and aim of the study: Bicuspid aortic valve (BAV), one of the most common congenital cardiac abnormalities, is the result of abnormal aortic leaflet formation during valvulogenesis. Recent studies have reported BAV to be associated with abnormal aortic stiffness, which has a negative impact on left ventricular (LV) diastolic function. The study aim was to investigate the relationship between LV diastolic function, as measured with two-dimensional speckle tracking echocardiography (2D-STE), and arterial stiffness.

Methods: A total of 38 patients with isolated BAV, and 18 age- and gender-matched healthy controls were enrolled prospectively. Patients with aortic valve velocity > 1.7 m/s, more than mild aortic regurgitation (AR) and ascending aorta diameter > 3.6 cm (indexed diameter > 2.1 cm/m2) were excluded. BAV was classified as either anterior-posterior (AP) orientation or right-left (RL) orientation. The LV diastolic function (E/A and E/Em ratio), left atrial (LA) volume index (LAVI), LA systolic strain and strain rate (SR) was assessed using echocardiography. Strain measurements were reported as longitudinal LA strain during ventricular systole (LA-Res), strain during late diastole (LA-Pump), and also as SR during ventricular contraction (LA-SR(s)), during passive ventricular filling (LA-SR(E)), and during active atrial contraction (LA-SR(A)) from four-chamber views. Arterial stiffness was evaluated by measuring the aortic pulse wave velocity (PWV), wave reflection was assessed by measuring the central systolic blood pressure (cSBP), central pulse pressure (cPP) and augmentation index (AIx) with applanation tonometry.

Results: The aortic diameter at the proximal ascending aorta was larger in patients with BAV than in controls. Compared to controls, the E/Em ratio and LAVI were significantly higher in BAV patients. Although PWV was higher in BAV patients than in controls, no differences were found between the groups in terms of cSBP, cPP and AIx. The BAV group was observed to have significant lower LA-Res and LA-Pump strain values compared to controls. Significant correlations were identified between the PWV and echocardiographic parameters of LV diastolic function determinants, such as LA-Res and LA-Pump. However, there were no significant differences between BAV subgroups in terms of LV diastolic parameters and PWV.

Conclusion: Patients with isolated BAV have early features of subclinical LV diastolic dysfunction, as measured with 2D-STE. In addition, aortic stiffness assessed by PWV was impaired. The LV diastolic parameters were related to aortic stiffness.

How to cite: Kocabay, G., Karabay, C. Y., Kalkan, S., Kalayci, A., Efe, S. C., Akgun, T., Bakal, R. B., Demir, S., Izgi, A., & Kirma, C. (2014). Relationship between left ventricular diastolic function and arterial stiffness in patients with bicuspid aortic valve. The Journal of heart valve disease, 23(3), 279–288.

Background and aim of the study: Estimation of stroke volume in the left ventricular outflow tract (LVOT) is a main limitation to aortic valve area (AVA) calculation by echocardiography when using the continuity equation. In this study, the hypothesis was tested that a hybrid method using thermodilution-derived cardiac output measurement and simultaneous Doppler estimation of the systolic ejection period and transvalvular aortic velocities could be used to accurately assess AVA in patients with low-gradient severe aortic stenosis (AS).

Methods: Eighteen patients with low mean gradient (< 40 mmHg) and nine patients with conventionally defined (> or = 40 mmHg) severe AS (< 1 cm2), as assessed by the echocardiographic continuity equation (baseline echocardiography), underwent catheterization and simultaneous Doppler recording of trans-aortic velocities.

Results: The mean pressure gradient was slightly lower by Doppler in the catheterization laboratory (35.8 +/-15.7 mmHg) compared to baseline echocardiography (37.4 +/- 15.2 mmHg) and invasive (38.5 +/- 16.6 mmHg) measurements (both p < 0.05). The AVA values were 0.72 +/- 0.12 cm2 during baseline echocardiography, 0.74 +/- 0.14 cm2 by catheterization, and 0.71 +/- 0.14 cm2 by the hybrid method (bias -0.01 +/- 0.11 cm2 and -0.02 +/- 0.08 cm2, versus echocardiography and catheterization, respectively; both p = NS).

Conclusion: The hybrid method is reasonably accurate in assessing AVA in patients with low-gradient severe AS. Although the continuity equation should be used in routine clinical practice in most patients, this method could serve as an alternative when the LVOT diameter and/or velocities seem questionable.

How to cite: Unger, P., Dedobbeleer, C., Stoupel, E., Preumont, N., Argacha, J. F., Berkenboom, G., & Van Camp, G. (2014). Quantification of low-gradient severe aortic stenosis using a hybrid approach combining Doppler echocardiography and thermodilution. The Journal of heart valve disease, 23(3), 271–278.

Background and aim of the study: Native, allograft, xenograft and bioprosthetic semilunar valves are all susceptible to calcific degeneration. However, intrinsic differences in baseline calcium and phosphorus tissue concentrations within mammalian normal valve structural components (e.g., cusps, sinus, vessel wall) additionally subdivided by tripartite regions (e.g., right-, left- and non-coronary leaflets) have never been systematically measured and reported. It was originally hypothesized that variations in normative tissue concentrations of calcium and phosphorus may correspond to subsequent clinical patterns of acquired dystrophic calcification; decellularization was also expected to reduce the tissue concentrations of these elements.

Methods: Native semilunar valves were freshly harvested from 12 juvenile sheep. Half of the valves were decellularized (six aortic and six pulmonary), while the other valves were flash-frozen at -80 degrees C within minutes of euthanasia as native valves. Elemental calcium and phosphorus concentrations were measured in the great vessels, sinus walls and cusps using inductively coupled plasma optical emission spectrometry (ICP-OES), and analyzed with non-parametric statistical tests.

Results: Calcium concentrations (microg/mg tissue; median (range) were similar in aortic native cusps (0.37 (0.21)), sinus walls (0.37 (0.09)) and aorta (0.37 (0.08)) (p = 0.8298). Pulmonary calcium concentrations were similar in cusps, but 10-25% higher in the native sinus (p = 0.0018) and pulmonary artery (p < 0.0001) compared to analogous aortic structures. All cusps had higher phosphorus concentrations than their respective conduit tissues. No tripartite regional variations were observed. Decellularization did not reduce the calcium content of cusps, but removed 50-55% of vessel and sinus wall calcium. However, up to 85% of phosphorus was removed from all valve tissues (p < 0.001).

Conclusion: There were no significant differences in normal tissue concentrations of calcium between aortic valve functional structures, and no semilunar tripartite regional differences in either semilunar valve complex. Thus, the distribution of baseline tissue calcium content of healthy young valves is not inherently predictive of selective or asymmetric anatomical patterns of valve degenerative calcification. Native semilunar cusps contain the highest phosphorus concentrations. Decellularization reduces all elemental concentrations except for cuspal calcium.

How to cite: Acharya, G., Armstrong, M., McFall, C., Quinn, R. W., Hilbert, S. L., Converse, G. L., Toth, P. B., Sherman, A. K., Lee, C. H., Lofland, G. K., & Hopkins, R. A. (2014). Calcium and phosphorus concentrations in native and decellularized semilunar valve tissues. The Journal of heart valve disease, 23(3), 259–270.