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Background: The modified Bentall procedure is still the treatment of choice for patients requiring combined replacement of the ascending aorta and aortic valve. We compared the long-term outcome of patients >65 years of age undergoing Bentall procedure with biological vs mechanical valved conduits in a multi institutional study., Methods: A total of 282 patients, undergoing a Bentall operation (January 1994-May 2015), with a biological (Group 1, 173 patients) or a mechanical (Group 2, 109 patients) conduit were reviewed, the primary outcome being analysis of late survival and freedom from major adverse events., Results: Hospital mortality was 5% (9 patients) and 2% (2 patients) for Group 1 and Group 2 (p = 0.2). Median follow-up was 77 months (range Q1-Q3: 49-111) for Group 1 vs 107 months (range Q1-Q3: 63-145) for Group 2 (p < 0.001). A not statistically significant advantage in late survival was found in patients receiving mechanical valved conduits (36% for Group 1 vs 58% for Group 2 at 12 years; p = 0.09), although freedom from major adverse events was similar between the 2 groups (33% in Group 1 vs 50% in Group 2 at 12 years; p = 0.3)., Conclusions: In conclusion, mechanical-valved conduits employed for the modified Bentall procedure show a trend towards an improved late survival in patients ≥65 years of age and particularly in those between 65 and 75 years, despite a higher incidence of major adverse events. Our results indicate the need for specific guidelines to better define the ideal age limit for each type of valved conduit., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Mitral PPM can be equated to residual mitral stenosis, which may halt the expected postoperative improvement of PH and concomitant functional tricuspid regurgitation (fTR). Aim of the present study is to evaluate the impact of mitral prosthesis-patient mismatch (PPM) on late tricuspid valve regurgitation and pulmonary hypertension (PH)., Methods: A total of 210 patients undergoing isolated mitral valve replacement (MVR) were investigated. Mitral valve effective orifice area was determined by the continuity equation and indexed for body surface area (EOAi) and PPM was defined as EOAi ≤ 1.2 cm(2)/m(2). Pulmonary hypertension (PH) was defined as systolic pulmonary artery pressure (sPAP) > 40 mmHg. Clinical and echocardiographic follow-up (median 27 months) was 100% completed. A total of 88/210 (42%) patients developed mitral PPM., Results: There were no significative differences in baseline and operative characteristics between patients with and without PPM. At follow-up, the prevalence of fTR ≥ 2+ (57%vs.22%; p = 0.0001), and PH (62%vs.24%;p < 0.0001) were significantly higher in patients with PPM. On multivariable regression analysis, EOAi (p < 0.0001) and preoperative left ventricular (LV) end-diastolic diameter (p < 0.0001) were found to be independently associated with fTR decrease after MVR. In addition, EOAi (p < 0.0001) and LV ejection fraction (p < 0.0001) were independently associated with PH decrease after MVR. No significant differences in mortality rates were found between patients having or not PPM., Conclusions: This study shows that mitral PPM is associated with the persistence of fTR and PH following MVR. These findings support the realization of tricuspid valve annuloplasty when PPM is anticipated at the time of operation., (© 2013.)

Background: Secondary mitral regurgitation (SMR) is generally reduced after isolated aortic valve replacement (AVR), but there is important interindividual variability in the magnitude of this reduction. Prosthesis-patient mismatch (PPM) may hinder normalization of left ventricular geometry and pressure overload following AVR, therefore we aimed to investigate the relationship between PPM and regression of SMR following AVR for aortic valve stenosis., Methods and Results: A total of 419 patients with AS who underwent isolated AVR at 2 institutions and presenting moderate SMR (mitral regurgitant volume 30 to 45 mL/beat) not considered for surgical correction were included in this study. Clinical and echocardiographic follow-up were completed at a median follow-up time of 37 months. PPM was defined as an indexed effective orifice area ≤0.85 cm(2)/m(2) and was found in 170/419 patients (40.6%). There were no significant differences in baseline and operative characteristics between patients with or without PPM. Patients with PPM had less regression of SMR following AVR compared with those with no PPM (change in mitral regurgitant volume: -11±4 versus -17±5 mL, respectively; P<0.0001). Variables significantly associated with postoperative change in mitral regurgitant volume on univariable analysis were entered in a multivariable linear regression model, which showed indexed effective orifice area (P<0.0001) and left atrial diameter (P=0.006) to be independently associated with mitral regurgitant volume improvement. Patients with PPM also had less postoperative improvement in 6-minute walking test distance (80±78 versus 42±41 m, P<0.0001)., Conclusions: PPM is associated with lesser regression of SMR following AVR. This unfavorable effect was associated with worse functional capacity. These findings emphasize the importance of operative strategies aiming to prevent PPM in patients with aortic valve stenosis and concomitant SMR.

Background: Patients with prosthesis-patient mismatch (PPM) continue to show some degrees of left ventricular hypertrophy after aortic valve replacement for aortic stenosis. The renin-angiotensin system plays a major role in promoting and sustaining hypertrophy. In a controlled, randomized study, we tested the hypothesis that the combination of angiotensin-converting enzyme inhibitors (ACEi) plus angiotensin II receptor blocker (ARB) can be more effective in decreasing hypertrophy than a largely employed association such as ACEi plus ß-blockers in PPM patients., Methods: We enrolled a total of 72 patients with aortic valve replacement and evidence of PPM (effective orifice area <0.85 cm(2)/m(2)) at postoperative echocardiography. At discharge, they were randomly assigned to ramipril plus candesartan (n = 36) or ramipril plus metoprolol (n = 36)., Results: At baseline, age, 24-hour blood pressure, left ventricular measurements, and transprosthetic gradients were similar between the two groups. After 12 months, the extent of 24-hour systolic and diastolic blood pressure decrease was similar between the two groups (-13.3% and 16.3% versus -12.3% and 15.8%, respectively; p = 0.7 and 0.8, respectively). Left ventricular mass index significantly decreased in both groups (ACEi plus ARB 165 ± 19 g/m(2) to 117 ± 17 g/m(2); p < 0.0001; ACEi plus β-blockers 161 ± 15 g/m(2) to 128 ± 20 g/m(2); p < 0.0001). However, patients receiving ACEi plus ARB had a higher decrease of left ventricular mass (-46 ± 15 g/m(2) versus -35 ± 12 g/m(2); p = 0.001) and a lower rate of residual left ventricular hypertrophy (22% versus 47%; p = 0.04)., Conclusions: This study shows that in patients with PPM, the association ACEi and ARB has a greater antiremodeling effect compared with ACEi and β-blockers, and is independent of blood pressure., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background and Aim of the Study: It has been shown previously that elevated plasma levels of B-type natriuretic peptide (BNP) and its N-terminal fragment (NT-pro-BNP) are related to the degree and progression of native aortic valve disease. In addition, NT-pro-BNP levels have been shown to decrease after successful aortic valve replacement (AVR). The presence of a valve prosthesis-patient mismatch (PPM) may affect the beneficial effects of AVR, however. The study aim was to investigate the relationship between PPM and NT-pro-BNP plasma levels late after AVR., Methods: A series of consecutive patients (42 males, 31 females; mean age 66 +/- 13 years) who had undergone isolated AVR between May 2004 and July 2007 was enrolled into the study. Patients with preoperative moderate to severe mitral regurgitation, coronary artery disease, left ventricular (LV) dysfunction (ejection fraction <45%) and serum creatinine >150 mmol/l were excluded. PPM was defined severe as an indexed effective orifice area (EOAi) < or = 0.65 cm2/m2, or moderate when the EOAi was 0.66-0.85 cm2/m2. Plasma NT-pro-BNP levels and echocardiographic assessments were performed in all patients during routine follow up after surgery., Results: The patients received either a biological (n = 42) or mechanical (n = 31) prosthesis. Among the patients, 21 had no PPM, 27 moderate PPM, and 25 severe PPM. At a median follow up of 18 months, the mean NT-pro-BNP plasma level was 532 pg/ml (95% CI: 393.1-671.6), and the mean LV mass index (LVMI) 120 +/- 4 g/m2, the LVEF 60 +/- 1%, the peak aortic prosthesis gradient 28 +/- 2 mmHg, and the EOAi 0.74 +/- 0.02 cm2/m2. Multivariate statistical analysis showed that NT-pro-BNP level correlated with age (beta = 0.57, p<0.0001), LVMI (beta = 0.32, p = 0.02), NYHA class (beta = 0.50, p = 0.003) and EOAi (beta = -0.38, p = 0.02)., Conclusion: The study results showed that NT-pro-BNP levels were independently related to PPM late after isolated AVR in patients with preserved LV function. However, further investigations are required to confirm these findings and to identify their clinical implications.

Objectives: The aims of this study were to compare long-term results after homograft versus Freestyle (Medtronic Inc., Minneapolis, Minnesota) aortic root replacement., Background: The ideal substitute for aortic root replacement remains undetermined., Methods: Between 1997 and 2005, 166 patients (age 65 +/- 8 years) undergoing total aortic root replacement were randomized to receive a homograft (n = 76) or a Freestyle bioprosthesis (n = 90). Six patients randomly assigned to homograft crossed over to Freestyle because of unavailability of suitably sized homografts. Median follow-up was 7.6 years (maximum 11 years; 1,035 patient-years). "Evolving" aortic valve dysfunction was defined as aortic regurgitation >/=2/4 and/or peak gradient >20 mm Hg., Results: Patient characteristics were comparable between groups. Concomitant procedures were performed in 44% and 47% of Freestyle and homograft patients, respectively (p = 0.5). Overall hospital mortality was 4.8% (1% for isolated root replacement). Eight-year survival was 80 +/- 5% in the Freestyle group versus 77 +/- 6% in the homograft group (p = 0.9). Freedom from need for reoperation at 8 years was significantly higher after Freestyle root replacement (100 +/- 0% vs. 90 +/- 5% after homograft replacement; p = 0.02). All reoperations were secondary to structural valve deterioration (n = 6). At last echocardiographic follow-up, actuarial freedom from evolving aortic valve dysfunction was 86 +/- 5% for Freestyle bioprostheses versus 37 +/- 7% for homografts (p < 0.001). Clinically, freedom from New York Heart Association functional class III to IV and freedom from valve-related complications were similar between groups (p = 0.7 and p = 0.9, respectively)., Conclusions: In this patient group, late survival is similar after homograft versus Freestyle root replacement. However, Freestyle aortic root replacement is associated with significantly less progressive aortic valve dysfunction and a lower need for reoperations., (Copyright (c) 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: This article describes a novel interactive method for quantitative evaluation of calcium deposits in the aortic valve by means of electron beam tomography data fusion technique., Methods: The technique relied on the use of hierarchic 3-dimensional free-form volume registration with fast global optimization between normally acquired and contrast-enhanced electron beam tomographic volume. A total of 66 contrast-enhanced electron beam tomographic scans of the aortic root were performed in 27 patients, 10 with native aortic valve disease (group A) and 17 from a prospective randomized trial of aortic root replacement (group B, 9 Freestyle grafts [Medtronic, Inc, Minneapolis, Minn] and 8 homografts). To validate the in vivo electron beam tomographic measurements, 5 patients from group A underwent electron beam tomographic scans before the operation and then had their own valves, explanted at the time of surgery, analyzed for calcium quantification by ex vivo electron beam tomography., Results: In group A, the mean (+/- SE) calcification score was 6560 +/- 2388, which correlated with peak gradients measured at echocardiography ( r = 0.93, P = .02). In group B, the mean (+/- SE) calcification score was 168 +/- 27, showing a tendency toward a lower calcification for Freestyle valves than for homografts at 2 years after implantation ( P = .052). A mean variability of 6% was found between in vivo electron beam tomographic scores of calcification and those measured on valve specimens after explantation., Conclusion: We describe a novel method to characterize the degree and location of calcification in both native valves and postoperative valve implants. The technique may be useful in the management of patients with aortic valve disease and has potential as a screening tool for high-risk patients to diagnose early valve calcification and possibly institute corrective measures.

Background and Aim of the Study: The full homograft root replacement has been regarded as the 'gold standard' for aortic valve replacement (AVR). Xenograft full root AVR may offer similar theoretical advantages, but no prospective randomized trials to compare the two valve substitutes have been reported to date., Methods: A total of 147 patients (mean age 66.2 years; range: 40-82 years) was randomized to undergo either Medtronic Freestyle (group F; n = 80) or homograft (group H; n = 67) root AVR. Coronary artery bypass grafting was associated with root AVR in 55 patients (37.4%). Follow up included routine clinical and echocardiographic assessments., Results: Overall, there were seven early deaths (4.8%). The early mortality rate for isolated root AVR was 2.1% in group F (1/47) and 2.2% in group H (1/45) (p = NS). There were four late deaths in group F, and two in group H. Actuarial survival was 83+/-5% and 84+/-4% (p = NS) at five years, in groups F and H, respectively. No patient required reoperation on the aortic valve. Overall, there were eight thromboembolic events and six anticoagulant-related bleeding events; these were equally divided between the two groups. After a median follow up of 45 months, most patients in both groups were in NYHA class I, and the mean trans-aortic gradient was 6+/-1 mmHg in group F and 5+/-2 mmHg in group H (p = NS). Mild aortic regurgitation was recorded in 1/26 patients (4%) of group F, and in 1/16 (6%) of group H., Conclusion: The Medtronic Freestyle porcine xenograft appears to be a good alternative to homografts for full aortic root replacement, at least in the mid term.

Background and Aim of the Study: Unstented bioprostheses offer better hemodynamics after aortic valve replacement. It has been reported recently that subcoronary implantation of the Freestyle valve may result in increased transvalvular velocities. In a prospective randomized trial, transvalvular velocities were investigated after implantation of a homograft or a Medtronic Freestyle bioprosthesis as a full root., Methods: A total of 137 patients was randomized to receive either a homograft (group H, n = 64) or a Freestyle (group F, n = 73) root replacement. Echocardiographic investigations were performed at six weeks, six months, and then yearly after surgery. Transvalvular and subvalvular velocities were recorded from each echocardiogram., Results: At follow up, none of the patients showed high transvalvular or subvalvular velocities (>2 m/s). At six weeks after surgery the transvalvular velocity was 1.5+/-0.3 m/s in group H (n = 51) and 1.7+/-0.3 m/s in group F (n = 56) (p = NS), while subvalvular velocities were 0.9+/-0.3 and 1.0+/-0.3 m/s, respectively (p = NS). These findings remained constant up to the three-year follow up, when transvalvular velocity was 1.6+/-0.4 m/s in group H (n = 10) and 1.6+/-0.2 m/s in group F (n = 15) (p = NS). Subvalvular velocities were 0.9+/-0.1 and 0.9+/-0.1 m/s, respectively (p = NS)., Conclusion: Full aortic root replacement and reimplantation of the coronary arteries either with the Medtronic Freestyle or the homograft valve produces near-normal transvalvular velocities less than were reported for the Freestyle in the subcoronary implantation.

Background and Aim of the Study: The changes in geometry of the aortic root during the cardiac cycle are thought to be essential for optimal valve function, both in terms of leaflet stress and dynamic behavior. Using cardiac magnetic resonance (CMR), the study aim was to determine aortic root distensibility of the homograft (group H) and the Medtronic Freestyle xenograft (group F) after aortic root replacement, from a prospective randomized trial., Methods: CMR was performed in 15 patients (six homografts, nine Freestyle) at six months and one year after surgery. Percentage change in aortic radius (PCR) and pressure strain elastic modulus (PSEM) were measured as indices of distensibility, and results related to left ventricular mass (LVM)., Results: At six months after surgery, mean PCR was 12+/-2.5 in group H and 12.9+/-6.1 in group F (p = NS), and PSEM was 428.5+/-69.8 and 493.5+/-72.7 g/cm2, respectively (p = NS). PCR was reduced to 10+/-1.7% in group H, and by 8.5+/-2.8% in group F (p = NS), while PSEM was increased to 520.5+/-87.3 and 825+/-420.4, respectively (p = NS) at the one-year follow up. Regression analysis showed a correlation between PCR and LVM (r = 0.52, p = 0.08) and LVM index (r = 0.46, p = 0.14), respectively. In addition, there was a relationship between PSEM, LVM and LVM index, suggesting that the stiffer the root wall, the higher the postoperative LVM., Conclusion: Up to one year after aortic root replacement, the wall of both the allogenic and xenogenic valves retained near-normal distensibility. For the first time, a correlation was demonstrated between the elastic properties of the aortic root and LVM. The longer-term behavior and clinical implications of these findings require further investigation.

Background and Aim of the Study: Regression of left ventricular hypertrophy (LVH) after aortic valve replacement has traditionally been measured by echocardiography. However, cardiovascular magnetic resonance (CMR) can be used to measure left ventricular function and mass more accurately and reproducibly. This translates into fewer patients being needed to demonstrate significant changes. The study aim was to demonstrate the feasibility of using CMR to measure left ventricular mass index (LVMI) and function in patients from a prospective randomized trial, and to compare homografts with the Medtronic Freestyle root replacement., Methods: Among 23 patients recruited, 17 had LVMI and function (end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF)) measured pre- and postoperatively using CMR (eight homograft, nine Freestyle)., Results: Significant regression of LVH was seen in both groups one year postoperatively (homograft LVMI 145+/-44 g/m2 preoperative versus 83+/-23 g/m2 one year postoperatively; Freestyle LVMI 140+/-28 g/m2 versus 93+/-21 g/m2, respectively). At six months there was significant regression in the xenograft group (from 140+/-28 to 106+/-22 g/m2; p <0.05) and a trend towards regression in the homograft group (from 145+/-44 to 103+/-25 g/m2; p = NS). There was also a trend towards a reduction in EDV, ESV and SV, and an increase in EF over one year in both groups., Conclusion: Regression of LVH was measured using CMR in patients after aortic root replacement and coronary implantation with the homograft and Medtronic Freestyle root replacement. Despite the small number of patients studied, it was possible to demonstrate the extent and pattern of regression of left ventricular mass in the two groups.

Background: We have previously shown, by means of electron beam tomography, the pattern of calcification of the aortic root wall of homografts and porcine xenografts after aortic root replacement. However, application of similar methods for cusp calcification raises specific problems that have not been addressed before., Methods: A new method for localizing and quantifying calcification of the aortic valve cusps has been evolved. Intravenous contrast-enhanced electron beam tomography was introduced to visualize the aortic cusps. This technique was applied to quantify cusp calcification in 37 patients after aortic root replacement with a homograft (group H) or a Medtronic Freestyle valve (group F) at set intervals between 6 months and 2 years. A calcification score in Hounsfield units (HU) and a calcified volume score in cubic millimeters were calculated., Results: The aortic leaflets were clearly visualized in all patients. The mean calcium score in the cusps was 28.8+/-64.4 HU in group F and 62.4+/-66.9 HU in group H (p = not significant). The mean calcified volume score was 327.0+/-425.9 mm3 in group F and 642.0+/-443.0 mm3 in group H (p = not significant)., Conclusions: Contrast enhancement electron beam tomography is a useful tool for quantification of calcium in the aortic valve leaflets. Our preliminary results show a tendency toward more calcification in the homografts. This needs to be studied further in a bigger cohort of patients followed up for longer periods.

Background and Aim of the Study: Unstented aortic valve substitutes offer many of the theoretical advantages of homografts such as superior hemodynamic performance and enhanced durability, particularly when inserted as a root. Many of these depend on the maintained flexibility of the valve components. Calcification of the aortic wall may adversely affect these phenomena. Electron beam computed tomography has been used to evaluate aortic wall calcification in patients undergoing aortic root replacement in a prospective randomized trial designed to compare the Medtronic Freestyle valve with the homograft valve replacement., Methods: Patients were followed with electron beam computed tomography scans of the aortic root at six-monthly intervals after surgery. A calcification score (Hounsfield units) and a calcified volume score (mm3) were obtained from each scan using a new modified technique. Results were related to hemodynamic data from echocardiography. The prevalence of calcification was also related to the homograft donor age., Results: Seventy-six patients (age range: 40-79 years) were randomized to root replacement with either homograft (n = 31) or Freestyle (n = 45) valves. Fifty-three scans of the aortic root were performed postoperatively in 37 patients. No statistical difference between the two groups was found at six and 12 months after surgery. However, after 18 months the calcified volume score was 5903.8+/-2356.8 mm3 in the homograft versus 2725.6+/-1500.5 mm3 in the Freestyle group (p = 0.017). There was a correlation between calcification score, calcified volume score and left ventricular mass (r = 0.323, p = 0.093 and r = 0.350, p = 0.068, respectively) on the one hand, and calcification score, calcified volume score and valve size on the other hand (r = 0.178, p = 0.466 and r = 0.068, p = 0.780, respectively)., Conclusions: Electron beam computed tomography provides a powerful tool for the detection of calcium in the aortic wall of valve grafts. There is a low rate of calcification during the first 18 months in the Medtronic Freestyle valve, and this appears to be lower than that observed in homografts. Longer-term follow up of the aortic root in these patients is required. This is an ongoing study.