Hemodynamic and clinical impact of prosthesis-patient mismatch in the aortic valve position and its prevention

Full-root Aortic Valve Replacement by Stentless Aortic Xenografts in Patients with Small Aortic Roots

In patients with small aortic roots who need an aortic valve replacement with biological valve substitutes, the implantation of the stented pericardial valve might not meet the functional needs. The implantation of a too-small stented pericardial valve, leading to an effective orifice area indexed to a body surface area less than 0.85 cm²/m², is regarded as prosthesis-patient mismatch (PPM). A PPM negatively affects the regression of left ventricular hypertrophy and thus the normalization of left ventricular function and the alleviation of symptoms. Persistent left ventricular hypertrophy is associated with an increased risk of arrhythmias and sudden cardiac death. In the case of predictable PPM, there are three options: 1) accept the PPM resulting from the implantation of a stented pericardial valve when comorbidities of the patient forbid the more technically demanding operative technique of implanting a larger prosthesis, 2) enlarge the aortic root to accommodate a larger stented valve substitute, or 3) implant a stentless biological valve or a homograft. Compared to classical aortic valve replacement with stented pericardial valves, the full-root implantation of stentless aortic xenografts offers the possibility of implanting a 3-4 mm larger valve in a given patient, thus allowing significant reduction in transvalvular gradients. However, a number of cardiac surgeons are reluctant to transform a classical aortic valve replacement with stented pericardial valves into the more technically challenging full-root implantation of stentless aortic xenografts. Given the potential hemodynamic advantages of stentless aortic xenografts, we have adopted full-root implantation to avoid PPM in patients with small aortic roots necessitating an aortic valve replacement. Here, we describe in detail a technique for the full-root implantation of stentless aortic xenografts, with emphasis on the management of the proximal suture line and coronary anastomoses. Limitations of this technique and alternative options are discussed.

Early and Mid-term Outcome of the St. Jude Medical Regent 19-mm Aortic Valve Mechanical Prosthesis. Functional and Haemodynamic Evaluation

BACKGROUND AND OBJECTIVES

The aim of the present study is to report the early and mid-term clinical and haemodynamic results of the St Jude Medical Regent 19-mm aortic mechanical prothesis (SJMR-19).

MATERIALS AND METHODS

Between January 2002 and January 2012, 265 patients with aortic valve disease underwent AVR (Aortic Valve Replacement) with a SJMR-19 (St Jude Medical Regent Nr.19). There were 51 males. Mean age was 67.5±12.72years and mean body surface area (BSA) was 1.67±0.14m2. Thirty-six patients required annulus enlargement. The mean follow-up was 34.5±18.8months (range 6-60 months). All patients underwent echocardiographic examination at discharge and within 1 year after surgery.

RESULTS

There were 14 (5.3%) hospital deaths. Six of the hospital deaths were identified in patients undergoing reoperation, significantly higher than patients undergoing first time operation (p=0.0001). Also the postoperative mortality was significantly higher in patients undergoing annulus enlargement versus patients not requiring annulus enlargement (p=0.02). The mean transprosthesis gradient at discharge was 19±9mmHg. At 6 months follow-up the mean NYHA FC class was 1.6±0.5 significantly lower than preoperatively 2.4±0.75 (p <0.0001). The M-TPG was 15.2±6.5mmHg within 1 year after surgery. Left ventricular mass (LVM) and indexed left ventricular mass (LVM_i) were significantly lower than preoperatively The actuarial survival and cumulative freedom from reoperation at 1, 2 and 3 years follow-up were 99.5%, 97.5%, 96.7% and 99.2%, 96.5%, 94.5% respectively. The cumulative actuarial free-events survival at 4 years was 92%. The Cox model identified age (p=0.015), LVEF≤35% (p=0.043), reoperation (p=0.031), combined surgery (p=0.00002), and annulus enlargement (p=0.015) as strong predictors for poor actuarial free-major events survival.

CONCLUSIONS

The SJMR-19 offers excellent postoperative clinical, haemodynamic outcome and LVM_i reduction in patients with small aortic annulus. These data demonstrate that the modern St Jude small mechanical protheses do not influence the intermediate free-reoperation survival.

Performance of the Labcor Dokimos Plus pericardial aortic prosthesis: a single-centre experience

Objectives

In patients with a small aortic annulus, aortic valve replacement (AVR) is frequently associated with high residual pressure gradients. Supra-annular pericardial aortic prostheses are gaining popularity due to the increased effective orifice areas (EOA) and resulting lower gradients. This study reports the clinical and echocardiographic results following implantation of the new supra-annular pericardial aortic prosthesis Dokimos Plus (Labcor, Belo Horizonte, Brazil).

Methods

Between October 2013 and July 2015, 137 patients (41% women, mean age: 74 years) underwent supra-annular AVR with or without concomitant procedures using the Dokimos Plus prosthesis in our department. Transthoracic echocardiography was performed pre- and postoperatively on all patients to assess haemodynamic parameters (gradients, acceleration time [AT], Doppler velocity indices [DVIs] and indexed EOA [EOAI]) and to detect paravalvular leakage (PVL). Data were collected retrospectively from our hospital databases.

Methods

Patients were grouped by prosthesis size: Most patients received 23-mm (57.6%), followed by 21-mm (19%), 25-mm (15.4%) and 27-mm (8%) prostheses. The mean EOAI in all groups was 1.1 ± 0.26 cm 2 /m 2 . Pressure gradients were low in all groups (mean: 8.9 ± 4.4 mmHg; peak: 18.8 ± 6.8 mmHg); AT and DVI were in the normal range according to American Society of Echocardiography/European Association of Cardiovascular Imaging recommendations (mean AT 73.3 ± 29 ms; mean DVI 0.5 ± 0.2). One patient had severe PVL and one presented with central regurgitation, both requiring re-intervention. The mortality rate was 5.1% ( n  = 7); none of the cases was associated with valve insufficiency.

Conclusions

The Dokimos prosthesis showed a satisfactory overall performance, presenting low gradients and DVIs as well as high EOAI. Further investigations are needed to analyse the cases of regurgitation and monitor long-term performance.

Effect of bioprostheses anti-calcification treatment: comparative follow-up between Mitroflow LX and Magna pericardial xenografts using a propensity score-weighted analysis

Objectives

The efficacy of anti-calcification treatment of bioprosthetic heart valves remains unclear. The aim of this study was to compare the clinical outcomes between Mitroflow LX valve, without anti-calcification treatment, and the Carpentier-Edwards Perimount Magna (P-Magna), with anti-calcification treatment.

Methods

Between 2005 and 2012, 625 consecutive patients underwent aortic valve replacement either with a Mitroflow LX ( n  = 329) or a P-Magna ( n  = 296). Variables regarding patient-related risk factors and operative data were accounted for an inverse probability of treatment weighting analysis. Then, adjusted survival outcomes and the rate of structural valve disease (SVD) were assessed for each group.

Results

Mean follow-up times were 4.1 ± 2.29 years and 3.9 ± 2.63 years, respectively ( P  = 0.34). Adjusted overall survival rate was higher in the P-Magna group than in the Mitroflow LX group at 8 years (69.1% vs 51.9%, respectively) [HR = 1.44, 95% CI: 1.01 to 2.06; P  = 0.0467]. Similarly, the 8-year cardiac-related survival rate was also higher in the P-Magna group [HR = 1.99, 95% CI: 1.19 to 3.32; P  = 0.0083]. One patient (0.8%) with P-Magna and 23 patients (18.5%) with Mitroflow LX group developed SVD (0.24% per patient-year vs 4.5% per patient-year, respectively; P  < 0.001). At 5 and 8 years, valve-related survival rates did not differ significantly between both groups [HR = 1.67, 95% CI: 0.95 to 2.95; P  = 0.075].

Conclusions

The P-Magna prosthesis showed significantly better overall and cardiac-related survival than the Mitroflow LX. The higher early SVD and reoperation rates seen with the Mitroflow LX prosthesis did not impact negatively on valve-related survival.

The modern role of transoesophageal echocardiography in the assessment of valvular pathologies

Despite significant advancements in the field of cardiovascular imaging, transoesophageal echocardiography remains the key imaging modality in the management of valvular pathologies. This paper provides echocardiographers with an overview of the modern role of TOE in the diagnosis and management of valvular disease. We describe how the introduction of 3D techniques has changed the detection and grading of valvular pathologies and concentrate on its role as a monitoring tool in interventional cardiology. In addition, we focus on the echocardiographic and Doppler techniques used in the assessment of prosthetic valves and provide guidance for the evaluation of prosthetic valves. Finally, we summarise quantitative methods used for the assessment of valvular stenosis and regurgitation and highlight the key areas where echocardiography remains superior over other novel imaging modalities.

Is Transesophageal Echocardiography Needed before Hospital Discharge in Patients after Bentall Surgery?

BACKGOUND

Whether transesophageal echocardiography (TEE) should be routinely performed before hospital discharge after Bentall surgery remains unclear. The investigators took advantage of this practice at their institution to evaluate its benefit.

METHODS

All patients who had undergone the Bentall procedure at Bichat Hospital from January 2010 to March 2014 were included. For each patient, transthoracic echocardiographic and transesophageal echocardiographic data and clinical events were retrospectively collected from the various reports.

RESULTS

One hundred ninety-eight patients underwent the Bentall procedure during the study period. Postoperative TEE was performed in 117 patients (59.1%), including nine with abnormalities observed on transthoracic echocardiography (a vibrating element on the new prosthetic valve, suspicion of peritubular complications in two patients, and aortic regurgitation in six patients). In 108 patients, routine TEE was performed (i.e., without clinical indication beyond baseline postoperative imaging). Patients with and those without routine TEE were identical, except for more frequent endocarditis as an indication for surgery in patients with routine TEE. Routine TEE did not reveal any new findings that prior transthoracic echocardiography had not shown. The most frequent finding on transthoracic echocardiography or TEE was periaortic hematoma, which sometimes led to the performance of computed tomography. This imaging did not change the care of the patients in this population.

CONCLUSIONS

This study does not support the performance of TEE after Bentall surgery during the in-hospital course in the absence of a specific indication. Baseline postoperative imaging using TEE or computed tomography should preferably be recommended beyond the early postoperative period after periaortic hematoma has resolved.

Modified versus Standard Mechanical Valved Aortic Conduit

The aim of this study was to compare the hemodynamic characteristics and early clinical results of a commercially available standard aortic conduit with those of a modified valved composite graft, which consists of a mechanical valve prosthesis sewn into a vascular tube and placed in a supraannular position. The modified conduit was placed in 40 patients (group 1) and the standard conduit in another 40 patients (group 2). The early postoperative mortality rates (within 30 days after surgery) were 0% in group 1 and 5% (2 patients) in group 2; the difference was not statistically significant. The mean geometric orifice area of the valve prosthesis was significantly larger in group 1 than in group 2 (3.7 ± 0.7 cm2 versus 2.9 ± 0.5 cm2). Early results showed a hemodynamic advantage of the modified conduit, with significantly lower transvalvular gradients.

Aortic valve replacement and prosthesis-patient mismatch in the era of trans-catheter aortic valve implantation

Objective

The treatment strategy for aortic stenosis (AS) has been changing due to newly developed valvular prostheses and trans-catheter aortic valve implantation (TAVI). To determine the role of new modalities for AS with a small aortic root, papers using the concept of prosthesis-patient mismatch (PPM) were reviewed.

Methods

First, to determine the cut-off value of the indexed effective orifice area (IEOA) for defining PPM, the studies of surgical aortic valve replacement (SAVR) with a follow-up longer than 5 years and a patient number larger than 500 were reviewed. Second, the papers comparing TAVI and SAVR were reviewed. Furthermore, the prevalence of PPM was reviewed, with the addition of papers on aortic root enlargement, sutureless AVR, and aortic valve reconstruction with autologous pericardium.

Results and conclusion

The results of the long-term survival after aortic valve replacement (AVR) have indicated that an IEOA less than 0.65 cm²/m² should be avoided in all cases, whereas the indications for patients with an IEOA between 065 and 0.85 cm²/m² should be determined by considering multiple factors. A large body size and younger age have a significantly negative influence on the long-term survival. In Asian population, the prevalence of PPM was low, despite the fact that the size of the aortic annulus was small. The IEOA after TAVI was larger than after surgical AVR in population-matched studies. To evaluate the role of TAVI and other modalities for a small aortic root, studies with a longer follow-up and larger volume are thus warranted.

Percutaneous transcatheter aortic valve implantation for degenerated surgical bioprostheses: the first case series in Asia with one-year follow-up

INTRODUCTION

Percutaneous transcatheter aortic valve implantation (TAVI) has become an established therapy for inoperable and high-surgical-risk patients with severe aortic stenosis. Although TAVI in patients with degenerated surgical aortic bioprostheses (i.e. valve-in-valve TAVI) is increasingly reported in Western studies, such data is lacking in Asian patients. We describe the initial experience of valve-in-valve TAVI in Asia.

METHODS

Eight patients who underwent valve-in-valve TAVI due to degenerated aortic bioprostheses were enrolled. The mechanism of bioprosthetic valve failure was stenotic, regurgitation or mixed. All procedures were performed via transfemoral arterial access, using the self-expanding CoreValve prosthesis or balloon-expandable SAPIEN XT prosthesis.

RESULTS

The mean age of the patients was 71.6 ± 13.2 years and five were male. Mean duration to surgical bioprosthesis degeneration was 10.2 ± 4.1 years. Valve-in-valve TAVI was successfully performed in all patients. CoreValve and SAPIEN XT prostheses were used in six and two patients, respectively. There were no deaths, strokes or permanent pacemaker requirement at 30 days, with one noncardiac mortality at one year. All patients experienced New York Heart Association functional class improvement. Post-procedure mean pressure gradients were 20 ± 11 mmHg and 22 ± 8 mmHg at 30 days and one year, respectively. Residual aortic regurgitation (AR) of more than mild severity occurred in one patient at 30 days. At one year, only one patient had mild residual AR.

CONCLUSION

In our experience of valve-in-valve TAVI, procedural success was achieved in all patients without adverse events at 30 days. Good clinical and haemodynamic outcomes were sustained at one year.

No clinical effect of prosthesis-patient mismatch after transcatheter versus surgical aortic valve replacement in intermediate- and low-risk patients with severe aortic valve stenosis at mid-term follow-up: an analysis from the NOTION trial

OBJECTIVES

Prosthesis-patient mismatch (PPM) after surgical aortic valve replacement (SAVR) for severe aortic valve stenosis (AVS) is common, but less common after transcatheter aortic valve replacement (TAVR) in patients considered at high risk for death after surgery. The objectives of this study were to determine incidence and clinical effect of PPM after SAVR and TAVR in a primarily low-risk patient group.

METHODS

Patients 70 years or older with severe isolated AVS, regardless of predicted operative mortality risk, were consecutively randomized 1:1 to TAVR using a self-expandable bioprosthesis (n = 145) or SAVR (n = 135). Post-procedure PPM was graded after 3 months as follows: Not present-mild, if indexed effective orifice area (iEOA) >0.85 cm²/m², moderate, if 0.65 cm²/m² < iEOA ≤ 0.85 cm²/m² and severe, if iEOA ≤0.65 cm²/m². Outcomes were major adverse cardiac and cerebrovascular events (MACCE, e.g. composite rate of all-cause death, stroke, myocardial infarction or valve reintervention), cardiac-related hospitalizations and New York Heart Association (NYHA) functional class after 2 years.

RESULTS

The incidence and the severity of PPM were significantly lower after TAVR compared with SAVR (severe, moderate, none-mild 14.0, 35.5, 50.4 vs 33.9, 36.7, 29.4%; P<0.001). PPM resulted in similar higher mean valve gradients at 3 months for both groups. Baseline characteristics related to severe PPM were younger age, absence of diabetes mellitus, lower mortality-risk score for TAVR, and younger age and higher body mass index for SAVR. At 2 years, there were numerical but no statistically significant differences between both TAVR and SAVR patients with severe and no severe PPM for MACCE (0.0 vs 12.8% for TAVR; P = 0.13, and 13.5 vs 7.0% for SAVR; P = 0.27), number of cardiac-related hospitalizations (mean ± standard deviation 0.4 ± 0.6 vs 0.6 ± 0.8; P = 0.23, and 0.4 ± 0.8 vs 0.5 ± 0.9; P = 0.70) and NYHA functional class (Class I/II/III/IV: 64.7/29.4/5.9/0.0 vs 62.1/34.7/3.2/0.0%, respectively; P = 0.91, and 71.4/25.7/2.9/0.0 vs 72.9/22.9/4.3/0.0%, respectively; P = 0.92).

CONCLUSIONS

The incidence of PPM was lower and less severe after TAVR compared with SAVR in intermediate- and low-risk patients with severe AVS. There were no significant differences in MACCE, cardiac-related hospitalizations or NYHA class after 2 years for patients with versus those without severe PPM.

Multicentre, propensity-matched study to evaluate long-term impact of implantation technique in isolated aortic valve replacement on mortality and incidence of redo surgery

OBJECTIVES

Studies suggest that the use of semicontinuous suture (SC) technique increases the risk of redo valve surgery after aortic valve replacement (AVR). The objective of this study was to identify 30-day mortality, rate of redo operation and long-term outcomes after AVR using either a semicontinuous suture or interrupted suture (IS) technique.

METHODS

A total of 1617 patients from 2 cardiothoracic centres, undergoing isolated AVR between April 2005 and August 2013 were included. AVR was performed using SC technique in 765 patients and IS technique in 852 patients. Data were collected prospectively and follow-up was obtained to date for all patients. We compared 30-day mortality, rate of redo operation and long-term mortality in SC and IS groups. One-to-one propensity-matching analysis was performed using IBM SPSS version 22 to evaluate outcomes.

RESULTS

Four hundred and eleven patients in the SC group were matched to 411 patients in the IS group (total of 822 patients) using propensity-score matching. The baseline characteristics were similar between SC and IS groups after matching. There were no statistically significant differences in 30-day mortality (3.9 vs 2.7%; P = 0.328), long-term mortality at 9-year follow-up (14.4 vs 15.3%; log-rank = 0.524) or rate of redo surgery (2.9 vs 2.0%; P = 0.320) between SC and IS, respectively. However, shorter cross-clamp time (51.9 ± 15.2 vs 60.9 ± 17.6 min; P < 0.001), bypass time (71.3 ± 23.0 vs 81.3 ± 37.8 min; P < 0.001) and the use of larger valve sizes (23.4 ± 2.1 vs 21.9 ± 2.2 mm; P < 0.001) were observed in SC patients compared with IS patients. Multivariate analysis did not show the suture technique as a significant determinant of redo valve surgery.

CONCLUSIONS

This multicentre study demonstrates that neither mortality nor the risk of redo surgery was influenced by the choice of implantation technique using semicontinuous vs interrupted suture techniques. The SC technique allowed shorter operations and larger size valves to be utilized.

Aortic Valve Replacement With Carpentier-Edwards: Hemodynamic Outcomes for the 19-mm Valve

BACKGROUND

To compare hemodynamic performance and clinical outcomes after aortic valve replacement for aortic stenosis with the 19-mm Carpentier-Edwards pericardial bioprosthesis versus larger valves.

METHODS

Between January 1998 and December 2013, 447 consecutive patients underwent aortic valve replacement for aortic stenosis with the Carpentier-Edwards Perimount (n = 61) or Magna bioprostheses (n = 386). Based on the implanted valve size, the patients were classified into three groups: a 19-mm group (n = 54), a 21-mm group (n = 154), and a 23-mm to 27-mm group (n = 239). The in vivo effective orifice area index was measured by transthoracic echocardiography 12 months after operation (n = 331). The mean follow-up time was 4.9 ± 3.5 (maximum 15.4) years.

RESULTS

There were three early deaths (0.7%). At 10 years, overall survival (84.1%) was unaffected by patient-prosthesis mismatch (18.7%, 62 patients), and freedom from structural valve deterioration and endocarditis was 100% and 97.1%, respectively. Although the 19-mm group was significantly older and had a higher incidence of patient-prosthesis mismatch (n = 14, 30.4%), there were no significant differences in early outcomes, overall survival, cardiac-related mortality, or serial reduction of left ventricular mass index in comparison with patients with a larger bioprostheses. Independent risk factors for all-cause mortality were age, male gender, combined coronary artery bypass graft, and low hemoglobin level.

CONCLUSION

The Carpentier-Edwards pericardial bioprosthesis appears to be associated with acceptable clinical outcomes and hemodynamic profile.

Early and mid-term outcome in terms of functional and hemodynamic performance of the st. Jude regent 19-mm aortic mechanical prosthesis versus 19-mm carpentier edwards aortic biological prosthesis

BACKGROUND

The aim of the present study is to compare the early and mid-term clinical and hemodynamic results of the aortic valve replacement (AVR) with a St Jude Medical Regent 19-mm prosthesis (SJMR-19) versus Carpentied-Edwars bovine pericardial 19-mm valve (CE-19).

METHODS

Between January 2002 and January 2012, 265 patients (Group I) and 58 patients (Group II) with underwent AVR with a SJMR-19 and CE-19 respectively. There were no significant differences between groups regarding the demographic and preoperative echocardiographic data. Thirty-six patients in Group I and 4 in Group II required annulus enlargement in association or not with septal myectomy. The mean follow-up was 34 ± 18.5 months (range 5-60 months).

RESULTS

There were 14 (5.3 %) hospital deaths in Group I versus 4 (6.8 %) in Group II (p = 0.86). The multivariate logistic regression analysis identified the LVEF ≤ 35 % (p = 0.001), combined operation (p = 0.0005), CPB (p = 0.033), age (p = 0.011), annulus enlargement (p = 0.0009), reoperation (p = 0.039) and chronic renal failure (p = 0.011) as strong predictors for early postoperative death. Within 1 year after surgery peak pulmonary artery pressure, interventricular septal and left ventricular posterior wall thickness decreased significantly in both groups. The M-TPG was 15.7 ± 6.5 mmHg in Group I versus 17 ± 7 mmHg in Group II (p = 0.19). The multivariate regression analysis revealed the annulus enlargement (p = 0.018), small EOAi (p = 0.00004), postoperative LVMi (p = 0.0001) and BSA (p = 0.019) as strong predictors for higher M-TPG. The postoperative LVMi was 119 ± 22.5 gm/m(2) in Group I and 122 ± 22 gm/m(2) in Group II (p = 0.37), significantly lower than the respective preoperative values 162.5 ± 34 gm/m(2) (Group I) and 168 ± 30 gm/m(2) (Group II). The actuarial survival and cumulative free-reoperation actuarial survival at 5 years follow-up were 96.7 and 94.5 % respectively in Group I and 97 and 91 % in Group II.. There were non significant differences between groups regarding the actuarial survival and cumulative free-reoperation survival. The Cox model identified the older age (p = 0.022), LVEF ≤ 35 % (p = 0.009), reoperation (p = 0.018), combined surgery (p = 0.00075) and annulus enlargement (p = 0.033) as strong predictors for poor actuarial free-reoperation survival.

CONCLUSIONS

Both the SJMR-19 and CE-19 offers excellent postoperative clinical and hemodynamic outcome in patients with small aortic annulus. The LV hypertrophy and transvalvular gradients are reduced significantly indenpendently of the employed SJMR-19 or CE-19 prosthesis. Our data support recent suggestions that small valve size does not influence intermediate free-reoperation survival. The CE-19 is an excellent alternative to SJMR-19 in old patients.

Does the St. Jude Regent 17-mm Offer Better Outcomes Than the Hemodynamic Plus 17-mm Aortic Valve Mechanical Prothesis?

OBJECTIVE

The aim of the present study is to report the early and mid-term clinical and hemodynamic results of a prospective trial investigating the clinical performance of the St. Jude Medical Regent 17 mm (SJMR-17) versus St. Jude Medical Hemodynamic Plus 17 mm (SJMHP-17).

MATERIALS AND METHODS

Between January 2000 and August 2013, 20 patients (Group I) with aortic valve (AV) stenosis underwent first time AV replacement with a SJMR-17 and nine patients (Group II) underwent AV replacement with a SJMHP-17. The mean follow-up was 58 ± 31 months.

RESULTS

There was one death in Group I. The end-diastolic IVS thickness and end-systolic posterior left ventricle (LV) wall thickness was reduced significantly in boths groups (p = 0.001 and p = 0.006 in Group I and p = 0.007 and p = 0.011 in Group II). The peak and mean transprosthesis gradients (P-TPG and M-TPG) were 29 ± 6.8 mmHg and 17.5 ± 4.5 mmHg in Group I, significantly lower than in Group II (55.2 ± 19.7 mmHg and 28.8 ± 7.7 mmHg). The postoperative left ventricular mass (LVM) and indexed left ventricular mass (LVMi) were reduced significantly in both groups versus the preoperative values. The postoperative LVMi was 114.5 ± 10.6 g/m(2) in Group I versus 127 ± 8 g/m(2) in Group II (p = 0.01). With dobutamine, heart rate, left ventricular ejection fraction, cardiac output, transprosthesis peak, and mean gradients increased significantly in both groups, however, the P-TPG and M-TPG were significantly higher in Group II (p = 0.026 and p = 0.022) despite a non-significant increase of the indexed effective orifice area.

CONCLUSIONS

The SJMR-17 can be employed with satisfactory postoperative clinical and hemodynamic outcomes in patients with small aortic annulus, especially in elderly patients offering better outcome than SJMHP-17.

Hemodynamics of 17-mm vs. 19-mm St. Jude Medical Regent and annulus enlargement

OBJECTIVE

We aimed to compare early and midterm clinical and hemodynamic outcomes of 17-mm vs. 19-mm St. Jude Medical Regent valves with concomitant aortic annulus enlargement.

METHODS

Between 1999 and 2012, 20 patients (group 1) underwent first-time aortic valve replacement with a 17-mm St. Jude Medical Regent valve, and 35 patients (group 2) had a 19-mm valve and concomitant aortic annulus enlargement. The mean follow-up was 81 ± 37 months (range 20-110 months).

RESULTS

There was one death in group 1 vs. 4 in group 2 (p > 0.05). The mean postoperative transprosthetic gradient was 17.5 ± 4.5 in group 1 and 17 ± 6.4 mm Hg in group 2 (p = 0.83), and 37 ± 10.7 and 32 ± 13 mm Hg, respectively, under stress (p = 0.17). Left ventricular mass and left ventricular mass index were reduced and similar in both groups. Postoperative effective orifice area index was higher in group 2 (0.85 ± 0.17 cm(2 )m(-2)) than group 1 (0.76 ± 0.2 cm(2 )m(-2); p > 0.05). A multivariate Cox model identified a 19-mm valve with aortic annulus enlargement (p = 0.032), functional class (p = 0.025), reoperation (p = 0.04), ejection fraction < 35% (p = 0.042), and combined surgery (p = 0.04) as strong predictors of poorer overall event-free survival.

CONCLUSIONS

The 17-mm St. Jude Medical Regent valve may be employed with satisfactory postoperative clinical and hemodynamic outcomes in patients with a small aortic annulus, as an alternative to a larger prothesis with aortic annulus enlargement.

Comparison of outcomes of patients with left ventricular ejection fractions ≤30% versus ≥30% having transcatheter aortic valve implantation (from the German Transcatheter Aortic Valve Interventions Registry)

Transcatheter aortic valve implantation (TAVI) is rapidly evolving in Germany. Especially severe reduced left ventricular ejection fraction (LVEF) is known as a prominent risk factor for adverse outcome in open heart surgery. Thus, the data of the prospective multicenter German Transcatheter Aortic Valve Interventions Registry were analyzed for outcomes in patients with severe depressed LVEF. Data of 1,432 patients were consecutively collected after transcatheter aortic valve implantation. Patients were divided into 2 groups (A: LVEF ≤30%, n = 169, age 79.9 ± 6.7 years, logES 34.2 ± 17.8%; B: LVEF >30%, n = 1,263, age 82.0 ± 6.1 years, logES 18.9 ± 12.0%), and procedural success rates, New York Heart Association classification, and quality of life were compared at 30 days and 1 year, respectively. Technical success was achieved in 95.9% (A) and 97.6% (B). Survival and the New York Heart Association classification at 30 days demonstrated an excellent outcome in both groups. There was a significant improvement according to the self-assessment in health condition (0 to 100 scale) with a much larger gain in group A (28 vs 19 patients, p <0.0001). Nevertheless, low cardiac output syndrome (12.3% vs 5.9%, p <0.01) and resuscitation (10.4% vs 5.6%, p <0.05) were more frequently seen in group A, contributing to a higher mortality at 30 days (14.3% vs 7.2%) and 1 year (33.7% vs 18.1%, p <0.001). In conclusion, this real-world registry demonstrated a comparably high success rate for patients with severe reduced LVEF and an early improvement in functional status as demonstrated by substantial benefit, despite a doubled postprocedural mortality.

Full-root aortic valve replacement with stentless xenograft achieves superior regression of left ventricular hypertrophy compared to pericardial stented aortic valves

BACKGROUND

Full-root aortic valve replacement with stentless xenografts has potentially superior hemodynamic performance compared to stented valves. However, a number of cardiac surgeons are reluctant to transform a classical stented aortic valve replacement into a technically more demanding full-root stentless aortic valve replacement. Here we describe our technique of full-root stentless aortic xenograft implantation and compare the early clinical and midterm hemodynamic outcomes to those after aortic valve replacement with stented valves.

METHODS

We retrospectively compared the pre-operative characteristics of 180 consecutive patients who underwent full-root replacement with stentless aortic xenografts with those of 80 patients undergoing aortic valve replacement with stented valves. In subgroups presenting with aortic stenosis, we further analyzed the intra-operative data, early postoperative outcomes and mid-term regression of left ventricular mass index.

RESULTS

Patients in the stentless group were younger (62.6 ± 13 vs. 70.3 ± 11.8 years, p < 0.0001) but had a higher Euroscore (9.14 ± 3.39 vs.6.83 ± 2.54, p < 0.0001) than those in the stented group. In the subgroups operated for aortic stenosis, the ischemic (84.3 ± 9.8 vs. 62.3 ± 9.4 min, p < 0.0001) and operative times (246.3 ± 53.6 vs. 191.7 ± 53.2 min, p < 0.0001) were longer for stentless versus stented valve implantation. Nevertheless, early mortality (0% vs. 3%, p < 0.25), re-exploration for bleeding (0% vs. 3%, p < 0.25) and stroke (1.8% vs. 3%, p < 0.77) did not differ between stentless and stented groups. One year after the operation, the mean transvalvular gradient was lower in the stentless versus stented group (5.8 ± 2.9 vs. 13.9 ± 5.3 mmHg, p < 0.0001), associated with a significant regression of the left ventricular mass index in the stentless (p < 0.0001) but not in the stented group (p = 0.2).

CONCLUSION

Our data support that full-root stentless aortic valve replacement can be performed without adversely affecting the early morbidity or mortality in patients operated on for aortic valve stenosis provided that the coronary ostia are not heavily calcified. The additional time necessary for the full-root stentless compared to the classical stented aortic valve replacement is therefore not detrimental to the early clinical outcomes and is largely rewarded in patients with aortic stenosis by lower transvalvular gradients at mid-term and a better regression of their left ventricular mass index.

Emerging trends in heart valve engineering: Part III. Novel technologies for mitral valve repair and replacement

In this portion of an extensive review of heart valve engineering, we focus on the current and emerging technologies and techniques to repair or replace the mitral valve. We begin with a discussion of the currently available mechanical and bioprosthetic mitral valves followed by the rationale and limitations of current surgical mitral annuloplasty methods; a discussion of the technique of neo-chordae fabrication and implantation; a review the procedures and clinical results for catheter-based mitral leaflet repair; a highlight of the motivation for and limitations of catheter-based annular reduction therapies; and introduce the early generation devices for catheter-based mitral valve replacement.

Determinants of clinical improvement after surgical replacement or transcatheter aortic valve implantation for isolated aortic stenosis

Background

Transcatheter aortic valve implantation (TAVI) is an alternative to surgical aortic valve replacement (SAVR) in patients with aortic stenosis (AS) and high surgical risk. Hemodynamic performance after TAVI is superior, but the impact of reverse remodeling on clinical improvement is controversial. We aim to address the differences in hemodynamic changes between SAVR and TAVI, and its correlation with LV remodeling and clinical improvement at 6 months follow-up.

Methods

Forty-two patients treated by TAVI were compared with 45 SAVR patients with a stented bioprosthesis. Clinical, 2D and 3D echocardiographic data were prospectively obtained before and six months after intervention.

Results

Patients had similar distribution for sex, body surface area and AS severity. TAVI patients were older, more symptomatic and had more comorbidities. They also had higher LV filling pressures, larger 3D indexed left atrium volume, but similar 3D indexed LV mass. At 6 months, TAVI patients had greater clinical improvement and higher effective orifice area index (EAOI), but only SAVR patients already had a significant decrease in 3D indexed LV mass and diastolic volume. In univariate analysis older age, NYHA class ≥ III, increase in EAOI and TAVI were related with functional class improvement. After multivariate analysis only NYHA class ≥ III (OR 8.81, CI:2.13-36.52; p = 0.003) and an increase in EAOI ≥ 105% (OR 3.87, CI:1.02-14.70; p = 0.04) were predictors of clinical improvement.

Conclusions

At 6 months, functional class improvement was greater after TAVI. Higher initial NYHA class and an increase in EAOI ≥ 105% were independently associated with functional enhancement. It is debatable if left ventricular remodeling is determinant for functional class improvement.

Electronic supplementary material

The online version of this article (doi:10.1186/1476-7120-12-41) contains supplementary material, which is available to authorized users.

Echocardiographic Assessment of Heart Valve Prostheses

Patients submitted to valve replacement with mechanical or biological prosthesis, may present symptoms related either to valvular malfunction or ventricular dysfunction from other causes. Because a clinical examination is not sufficient to evaluate a prosthetic valve, several diagnostic methods have been proposed to assess the functional status of a prosthetic valve. This review provides an overview of echocardiographic and Doppler techniques useful in evaluation of prosthetic heart valves. Compared to native valves, echocardiographic evaluation of prosthetic valves is certainly more complex, both for the examination and the interpretation. Echocardiography also allows discriminating between intra- and/or peri-prosthetic regurgitation, present in the majority of mechanical valves. Transthoracic echocardiography (TTE) requires different angles of the probe with unconventional views. Transesophageal echocardiography (TEE) is the method of choice in presence of technical difficulties. Three-dimensional (3D)-TEE seems to be superior to 2D-TEE, especially in the assessment of paravalvular leak regurgitation (PVL) that it provides improved localization and analysis of the PVL size and shape.

Age-related changes in biomechanical properties of transgenic porcine pulmonary and aortic conduits

The limitations associated with conventional valve prosthesis have led to a search for alternatives. One potential approach is tissue engineering. Most tissue engineering studies have described the biomechanical properties of heart valves derived from adult pigs. However, because one of the factors affecting the function of valve prosthesis after implantation is appropriate sizing for a given patient, it is important to evaluate the usefulness of a heart valve given the donor animal's weight and age. The aim of this study was to evaluate how the age of a pig can influence the biomechanical and hemodynamical properties of porcine heart valve prosthesis after acellularization. Acellular porcine aortic and pulmonary valve conduits were used. Hearts were harvested from animals differing in weight and age. The biomechanical properties of the valves were then characterized using a uniaxial tensile test. Moreover, computer simulations based on the finite element method (FEM) were used to study the influence of biomechanical properties on the hemodynamic conditions. Studying biomechanical and morphological changes in porcine heart valve conduits according to the weight and age of the animals can be valuable for developing age-targeted therapy using tissue engineering techniques.

Prosthesis-patient mismatch after transcatheter aortic valve implantation: impact of 2D-transthoracic echocardiography versus 3D-transesophageal echocardiography

To investigate the role of 2D-transthoracic echocardiography (2D-TTE) and 3D-transesophageal echocardiography (3D-TEE) in the determination of aortic annulus size prior transcatheter aortic valve implantation (TAVI) and its' impact on the prevalence of patient prosthesis mismatch (PPM). Echocardiography plays an important role in measuring aortic annulus dimension in patients undergoing TAVI. This has great importance since it determines both eligibility for TAVI and selection of prosthesis type and size, and can be potentially important in preventing an inadequate ratio between the prosthetic valvular orifice and the patient's body surface area, concept known as prosthesis-patient mismatch (PPM). A total of 45 patients were studied pre-TAVI: 20 underwent 3D-TEE (men/women 12/8, age 84.8 ± 5.6) and 25 2D-TTE (men/women 9/16, age 84.4 ± 5.4) in order to measure aortic annulus diameter. The presence of PPM was assessed before hospital discharge and after a mean period of 3 months. Moderate PPM was defined as indexed aortic valve area (AVAi) ≤ 0.85 cm(2)/m(2) and severe PPM as AVAi < 0.65 cm(2)/m(2). Immediately post-TAVI, moderate PPM was present in 25 and 28 % of patients worked up using 3D-TEE and 2D-TTE respectively p value = n.s) and severe PPM occurred in 10 % of the patients who underwent 3D-TEE and in 20 % in those with 2D-TTE (p value = n.s). The echocardiographic evaluation 3 months post-TAVI showed 25 % moderate PPM in the 3D-TEE group compared with 24 % in the 2D-TTE group (p value = n.s) and no cases of severe PPM in the 3DTEE group comparing to 20 % in the 2D-TTE group (p = 0.032). Our results indicate a higher incidence of severe PPM in patients who performed 2DTTE compared to those performing 3DTEE prior TAVI. This suggests that the 3D technique should replace the 2DTTE analysis when investigating the aortic annulus diameter in patients undergoing TAVI.

Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis

Background

Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm2 m−2, has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus.

Methods

Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m2) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery.

Results

Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm2 m−2. Moderate mismatch, defined as effective orifice area index ≤0.85 cm2 m−2, developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe.

Conclusions

Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients.

Hemodynamic outcomes of transcatheter aortic valve implantation with the CoreValve system: an early assessment

BACKGROUND AND AIMS

Transcatheter aortic valve implantation (TAVI) is an established method for the treatment of high-risk patients with aortic stenosis (AS). The beneficial effects of TAVI in cardiac hemodynamics have been described in recent studies, but those investigations were mostly performed after an interval of more than 6 months following aortic valve implantation. The aim of this study is to investigate the acute and short-term alterations in hemodynamic conditions using the echocardiography outcomes in patients undergoing TAVI.

METHODS AND RESULTS

A total of 60 patients (26 males, 34 females; age 84·7 ± 5·8) who underwent TAVI with CoreValve system were included in the study. Echocardiography was performed before hospital discharge and at 3 months follow-up. As expected, TAVI was associated with an immediate significant improvement in aortic valve area (AVA) (from 0·64 ± 0·16 cm(2) to 1·67 ± 0·41 cm(2) , P-value<0·001) and mean gradient (from 51·9 ± 15·4 mmHg to 8·8 ± 3·8 mmHg, P-value<0·001). At 3-month follow-up, systolic LV function was augmented (EF: 50 ± 14% to 54 ± 11%, P-value = 0·024). Left ventricle (LV) mass and left atrium (LA) volume were significantly reduced (LV mass index from 126·5 ± 30·5 g m(-2) to 102·4 ± 32·4 g m(-2) ; LA index from 42·9 ± 17·3 ml m(-2) to 33·6 ± 10·6 ml m(-2) ; P-value<0·001 for both). Furthermore, a decrement in systolic pulmonary artery pressure (SPAP) from 47·5 ± 13·5 mmHg to 42·5 ± 11·2 mmHg, P-value = 0·02 was also observed. Despite the high incidence of paravalvular regurgitation (PVR) (80%), most of the patients presented mild or trace PVR and no significant progress of the regurgitation grade was seen after 3 months.

CONCLUSION

This study demonstrates that the beneficial effects of TAVI in cardiac function and hemodynamics occur already after a short period following aortic valve implantation.