Impact of Suture Techniques for Aortic Valve Replacement on Prosthesis-Patient Mismatch

Continuous or interrupted pledgeted suture technique in stented bioprosthetic aortic valve replacement: a comparison of in-hospital outcomes

BACKGROUND

There is ambiguity in the literature regarding the continuous suture technique (CST) for aortic valve replacement (AVR). At our center, there has been a gradual shift towards CST over the interrupted pledgeted technique (IPT). This study aims at comparing outcomes for both techniques.

METHODS

We performed a retrospective analysis of a single-center study of patients undergoing AVR between January 2011 and July 2020. Patients were divided into two groups: Continuous suture technique and interrupted pledget-reinforced sutures. The pre-operative and In-hospital clinical characteristics and echocardiographic hemodynamics (i.e. transvalvular gradients and paravalvular leakage) were compared between CST and IPT.

RESULTS

We compared 791 patients with CST to 568 patients with IPT (median age: 73 and 74 years, respectively, p = 0.02). In CST there were 35% concomitant procedure vs. 31% in IPT (p = 0.16). Early mortality was 3.2% in CST versus 4.8% in IPT (p = 0.15), and a second cross-clamp due to a paravalvular-leak in 0.5% vs. 1.2%, respectively (p = 0.22). The CST was not associated with new-onset conduction-blocks mandating pacemaker implants(OR 1.07, 95% CI 0.54-2.14; P = 0.85). The postoperative gradients on echocardiography were lower in CST compared to IPT, especially in smaller annuli (peak gradients: 15.7mmHg vs. 20.5mmHg, in valve size < 23 mm, p < 0.001).

CONCLUSIONS

The continuous suture technique was associated with lower postoperative gradients and shorter cross-clamp time compared to interrupted pledgeted technique. Differences in paravalvular leaks were non-significant, although slightly less in the continuous suture technique. There were no further differences in valve-related complications. Hence, continues suture technique is safe, with better hemodynamics compared to the interrupted pledgeted technique. This may be of clinical importance, especially in smaller size annular size.

Figure of eight suture technique in aortic valve replacement decreases prosthesis-patient mismatch

BACKGROUND

While the pledget suture technique has been the standard for surgical aortic. valve replacement (AVR), discussion continues regarding the possibility of the nonpledget suture technique to produce superior structural and hemodynamic parameters. This study aims to assess the effectiveness of the figure-of-eight suture technique in AVR, as determined by the incidence of prosthesis-patient mismatch (PPM).

METHODS

We reviewed records of patients (N = 629) who underwent a surgical AVR procedure between January 2011 and July 2018 at a single institution. Indexed effective orifice area values and PPM incidence were calculated from implanted valve size and patient body surface area. Incidence of none, moderate, and severe PPM was compared across AVR suture techniques.

RESULTS

A total of 570 pledget and 59 figure-of-eight patients were compared for incidence of PPM. Patients who received AVR with the pledget suture technique had significantly lower echocardiographic measurements of baseline ejection fraction than patients who had received AVR with the figure-of-eight suture technique (p = 0.003). Patients who received the figure-of eight suture had a 14% decrease in moderate PPM compared to patients who received the pledget suture (p = 0.022). Patients who received the figure-of-eight suture also had a significantly higher rate of no PPM (p = 0.044).

CONCLUSIONS

The use of the figure-of-eight suture technique in AVR can reduce the incidence of moderate PPM. While the pledget suture is the standard technique in AVR, the figure-of-eight suture technique may offer better structural and hemodynamic outcomes, especially for patients with a smaller aortic annulus.

Pledgeted versus nonpledgeted sutures in aortic valve replacement: Insights from a prospective multicenter trial

Objective

The objective of this study was to compare short- and midterm clinical and echocardiographic outcomes according to the use of pledgeted sutures during aortic valve replacement.

Methods

Patients with aortic stenosis or regurgitation requiring aortic valve replacement were enrolled in a prospective cohort study to evaluate the safety of a new stented bioprosthesis. Outcomes were analyzed according to the use of pledgets (pledgeted group) or no pledgets (nonpledgeted group). The primary outcome was a composite of thromboembolism, endocarditis, and major paravalvular leak at 5 years of follow-up. Secondary outcomes included multiple clinical endpoints and hemodynamic outcomes. Propensity score matching was performed to adjust for prognostic factors, and subanalyses with small valve sizes (<23 mm) and suturing techniques were performed.

Results

The pledgeted group comprised 640 patients (59%), and the nonpledgeted group 442 (41%), with baseline discrepancies in demographic characteristics, comorbidities, and stenosis severity. There were no differences between groups in any outcome. After propensity score matching, the primary outcome occurred in 41 (11.7%) patients in the pledgeted and 36 (9.8%) in the nonpledgeted group (P = .51). The effective orifice area was smaller in the pledgeted group (P = .045), whereas no difference was observed for the mean or peak pressure gradient. Separate subanalyses with small valve sizes and suturing techniques did not show relevant differences.

Conclusions

In this large propensity score-matched cohort, comprehensive clinical outcomes were comparable between patients who underwent aortic valve replacement with pledgeted and nonpledgeted sutures up to 5 years of follow-up, but pledgets might lead to a slightly smaller effective orifice area in the long run.

Bioprosthetic Aortic Valve Hemodynamics: Definitions, Outcomes, and Evidence Gaps: JACC State-of-the-Art Review

A virtual workshop was organized by the Heart Valve Collaboratory to identify areas of expert consensus, areas of disagreement, and evidence gaps related to bioprosthetic aortic valve hemodynamics. Impaired functional performance of bioprosthetic aortic valve replacement is associated with adverse patient outcomes; however, this assessment is complicated by the lack of standardization for labelling, definitions, and measurement techniques, both after surgical and transcatheter valve replacement. Echocardiography remains the standard assessment methodology because of its ease of performance, widespread availability, ability to do serial measurements over time, and correlation with outcomes. Management of a high gradient after replacement requires integration of the patient's clinical status, physical examination, and multimodality imaging in addition to shared patient decisions regarding treatment options. Future priorities that are underway include efforts to standardize prosthesis sizing and labelling for both surgical and transcatheter valves as well as trials to characterize the consequences of adverse hemodynamics.

Early outcomes of patient-prosthesis mismatch following aortic valve replacement

INTRODUCTION

Patient-prosthesis mismatch (PPM) has been associated with numerous short- and long-term adverse events. This study aimed to evaluate the effect of PPM on early postoperative results after aortic valve replacement (AVR) in daily practice.

METHODS

In this single-centre retrospective study, 150 non-consecutive patients from March 2019 to January 2020 with clinically indicated AVR with/without concomitant surgery were analysed. The study protocol included operative mortality, complication rate, and pre- and postoperative echocardiographic data. PPM was considered severe with indexed effective orifice area at <0.65 cm²/m², moderate at 0.65-0.85 cm²/m² and none at >0.85 cm²/m².

RESULTS

Moderate PPM was observed in 16 patients (10.6%). No patient had severe PPM. PPM was not related to early mortality (r = 0.40, p = 0.630), intra- (r = -0.076, p = 0.352) and postoperative (r = -0.0134, p = 0.102) events.

CONCLUSION

In this study, moderate PPM was a frequent finding after AVR, whereas severe PPM was not observed. PPM did not affect the early results after AVR. A long-term follow-up study in a large patient population is required to assess the actual influence of residual PPM.

Surgical aortic valve replacement in small aortic annulus

BACKGROUND

Although aortic valve replacement (AVR) has been the standard of treatment for severe aortic stenosis, a small aortic annulus (SAA) poses significant challenges. Improvements in valve designs and evolution in surgical techniques have led to improved outcomes, however, the ideal prosthetic valve remains elusive.

METHODS

We performed a comprehensive literature review to discuss the surgical management of aortic stenosis, with a special focus on patients with SAA.

RESULTS

Stentless valves and root replacement techniques have been shown to overcome the hemodynamic challenges associated with conventional stented bioprostheses, but are technically challenging and require longer cross-clamp times. Sutureless and rapid deployment valves mitigate the long operative time while maintaining the hemodynamic advantages. The use of transcatheter AVR has emerged as another reasonable alternative and has shown promise among patients with SAA, however, long-term outcomes are awaited.

CONCLUSION

There is no consensus regarding the type of valve prosthesis or replacement technique among patients with SAA. Consideration of patient comorbidities and valvular anatomy is paramount in planning the optimal strategy for AVR. Further long-term clinical trials are necessary to assess outcomes and achieve progress toward the development of the ideal prosthesis.

Non-pledget commissural suture technique to avoid atrioventricular block

Here, we report our unique "non-pledget commissural suture technique" to avoid complete atrioventricular block during surgical aortic valve replacement, whereby all commissural stiches are made in a figure-of-eight fashion without a pledget. Then, standard stiches in a non-everting fashion are made using pledget sutures and a prosthetic valve is implanted at the supra-annular position. Among 152 evaluated patients, only five patients experienced complications, including three left bundle branch blocks, one postoperative pacemaker implantation, and one moderate paravalvular leak. Based on the high success rate, our technique may be a reasonable alternative for surgical aortic valve replacement.

Aortic Annular Enlargement in the Elderly: Short and Long-Term Outcomes in the United States

BACKGROUND

Patient prosthesis mismatch is associated with significant long-term morbidity and mortality after aortic valve replacement, but the role and outcomes of annular enlargement (AE) remain poorly defined. We hypothesized that increasing rates of AE may lead to improved outcomes for patients at risk for severe patient prosthesis mismatch.

METHODS

Patients over age 65 years undergoing surgical aortic valve replacement with or without coronary artery bypass grafting from 2008-2016 in The Society of Thoracic Surgeons Adult Cardiac Surgery Database with matching Centers for Medicare & Medicaid Services data were included (n=189,268). Univariate, multivariate, and time-to-event analysis was used to evaluate the association between AE and early and late outcomes. Patients were stratified by projected degree of patient prosthesis mismatch based on calculated effective orifice area index.

RESULTS

A total of 5412 (2.9%) patients underwent AE. The Society of Thoracic Surgeons Adult Cardiac Surgery Database-predicted mortality was similar between AE and non-AE groups (2.97% vs 2.99%, P = .052). Patients undergoing AE had higher risk-adjusted rates of 30-day complications and death (5.4% vs 3.4%, P < .0001), but no differences in long-term rates of stroke, heart failure re-hospitalization,s or aortic valve reoperation. Survival analysis demonstrated a higher risk of mortality with AE during the first 3 years, after which the survival curves cross, favoring AE.

CONCLUSIONS

These data suggest that annular enlargement during surgical aortic valve replacement is associated with increased short-term risk in a Medicare population. Survival curves crossed after 3 years, which may portend a benefit in select patients. However, annular enlargement is still only performed in the minority of patients who are at risk for patient prosthesis mismatch.

Simple Interrupted Suturing for Aortic Valve Replacement in Patients with Severe Aortic Stenosis

Background

Attaining an adequate effective orifice area (EOA) is definitive goal in aortic valve replacement (AVR). The simple interrupted suture (SIS) technique could be a solution to achieve this goal, but limited data are available in the literature. This study aimed to compare hemodynamic differences between the SIS and non-everting mattress suture (NMS) techniques.

Methods

From our database, 215 patients who underwent AVR for severe aortic stenosis were extracted to form the overall cohort. From March 2015 to November 2016, the SIS technique was used in 79 patients, while the NMS technique was used in 136 patients. Hemodynamic outcomes were evaluated, as detected by transthoracic echocardiography and computed tomography.

Results

There were no significant differences in baseline characteristics between the 2 groups. On immediate postoperative echocardiography, the SIS group showed a significantly wider EOA (1.6±0.4 vs. 1.4±0.5 cm², p=0.007) and a lower mean pressure gradient (PG) (13.3±5.4 vs. 17.0±6.0 mm Hg, p<0.001) than the NMS group. On follow-up echocardiography, the SIS group continued to have a wider EOA (1.6±0.4 vs. 1.4±0.3 cm², p<0.001) and a lower mean PG (11.0±5.1 vs. 14.1±5.5 mm Hg, p<0.001). There was no significant difference in paravalvular leakage.

Conclusion

The SIS technique for AVR was associated with a wider EOA and a lower mean PG. The SIS technique could be a reasonable option for AVR.

Determinants of effective orifice area in aortic valve replacement: anatomic and clinical factors

Background

Obtaining adequate effective orifice area (EOA) in surgical aortic valve replacement (SAVR) is important to minimize pressure gradients across the prosthetic aortic valve (AV) and improve clinical outcomes. However, the predictors of EOA are unclear.

Methods

From July 2011 to March 2016, patients undergoing SAVR who were preoperatively evaluated using a computed tomography (CT) on the aortic root were enrolled. Indexed EOA (iEOA) was used as an indicator of prosthetic AV opening area. The aortic root parameters investigated were the annular diameter (max and min), annular perimeter, annular area, and maximal dimensions of the proximal ascending aorta. These variables were evaluated as predictors of EOA, and an individual surgeon was incorporated in analysis for verifying surgeon dependent factors.

Results

Among the 710 patients included in this study [age: 64.9±10.8 years; females: n=285 (40.1%)], 370 (52.1%) were implanted with bio-prosthesis. Mean prosthetic iEOA was 1.1±0.3 cm²/m². Univariable linear regression analysis showed that all indexed aortic root parameters (maximal and minimal annular diameters, annular perimeter, annular area, and sinus dimensions) were significantly associated with iEOA (P<0.001). Multivariable analysis showed that indexed aortic annular area, indexed maximal diameter of the Valsalva sinus, female sex, and bio-prosthesis, supra-annular type prosthesis and surgeon were significant and independent determinants of iEOA (adjusted R²=0.513, P<0.001).

Conclusions

Aortic annular area and Valsalva sinus diameter are independent determinants for iEOA measured by preoperative CT; surgeon-dependent factors are also significant determinants in SAVR.