Redo Valve Surgery—Current Status and Future Perspectives

Clinical and Surgical Evaluations of Reoperation After Mechanical Mitral Valve Replacement Due to Different Etiologies

Background:

This study aimed to evaluate the clinical and surgical characteristics of patients who required reoperation after mechanical mitral valve replacement (MVR).

Methods:

We retrospectively identified 204 consecutive patients who underwent reoperation after mechanical MVR between 2009 and 2018. Patients were categorized according the reason for reoperation (perivalvular leakage, thrombus formation, or pannus formation). The patients' medical and surgical records were studied carefully and the rates of in-hospital complications were calculated.

Results:

The mean age was 51±12 years and 44% of the patients were male. The reasons for reoperation were perivalvular leakage (117 patients), thrombus formation (35 patients), and pannus formation (52 patients). The most common positions for perivalvular leakage were at the 6–10 o'clock positions (proportions of ≥25% for each hour position). Most patients had an interval of >10 years between the original MVR and reoperation. The most common reoperation procedure was re-do MVR (157 patients), and 155 of these patients underwent concomitant cardiac procedures. There were 10 in-hospital deaths and 32 patients experienced complications. The 10-year survival rate was 82.2 ± 3.9% in general, and the group of lowest rate was patients with PVL (77.5 ± 5.2%). The independent risk factors were “male” (4.62, 95% CI 1.57–13.58, P = 0.005) and “Hb <9g/dL before redo MV operation” (3.45, 95% CI 1.13–10.49, P = 0.029).

Conclusion:

Perivalvular leakage was the most common reason for reoperation after mechanical MVR, with a low survival rate in long term follow-up relatively.

Sutureless Valve in Repeated Aortic Valve Replacement: Results from an International Prospective Registry

OBJECTIVE

To report early and midterm results registry of patients undergoing repeated aortic valve replacement (RAVR) with sutureless prostheses from an international prospective registry (SURE-AVR).

METHODS

Between March 2011 and June 2019, 69 patients underwent RAVR with self-expandable sutureless aortic bioprostheses at 22 international cardiac centers.

RESULTS

Overall mortality was 2.9% with a predicted logistic EuroSCORE II of 10.7%. Indications for RAVR were structural valve dysfunction (84.1%) and infective prosthetic endocarditis (15.9%) and were performed in patients with previously implanted bioprostheses (79.7%), mechanical valves (15.9%), and transcatheter valves (4.3%). Minimally invasive approach was performed in 15.9% of patients. Rate of stroke was 1.4% and rate of early valve-related reintervention was 1.4%. Overall survival rate at 1 and 5 years was 97% and 91%, respectively. No major paravalvular leak occurred. Rate of pacemaker implantation was 5.8% and 0.9% per patient-year early and at follow-up, respectively. The mean transvalvular gradient at 1-year and 5-year follow-up was 10.5 mm Hg and 11.5 mm Hg with a median effective orifice area of 1.8 cm²and 1.8 cm², respectively.

CONCLUSIONS

RAVR with sutureless valves is a safe and effective approach and provides excellent clinical and hemodynamic results up to 5 years.

A Systolic Murmur Late after Infective Endocarditis: Looking for the Guilty

Aortic location of infective endocarditis is a risk factor for perivalvular extension of infection, even when a native valve is involved. We report the case of a 50-year-old man with a systolic murmur and a history of previous aortic valve infective endocarditis requiring cardiac surgery. A thorough echocardiographic assessment, including three-dimensional transesophageal echocardiography, clearly demonstrated the presence of two distinct postinfective complications, i.e., a fistula of the mitral-aortic intervalvular curtain communicating in systole with the left atrium and an acquired Gerbode-type ventricular septal defect. Our case highlights the pivotal role of echocardiography for a correct and comprehensive diagnostic assessment in the complex scenarios frequently encountered after infective endocarditis.

How to treat severe symptomatic structural valve deterioration of aortic surgical bioprosthesis: transcatheter valve-in-valve implantation or redo valve surgery?

The optimal management of aortic surgical bioprosthesis presenting with severe symptomatic structural valve deterioration is currently a matter of debate. Over the past 20 years, the number of implanted bioprostheses worldwide has been rapidly increasing at the expense of mechanical prostheses. A large proportion of patients, however, will require intervention for bioprosthesis structural valve deterioration. Current options for older patients who often have severe comorbidities include either transcatheter valve-in-valve (TVIV) implantation or redo valve surgery. The emergence of TVIV implantation, which is perceived to be less invasive than redo valve surgery, offers an effective alternative to surgery for these patients with proven safety and efficacy in high-risk patient groups including elderly and frail patients. A potential caveat to this strategy is that results of long-term follow-up after TVIV implantation are limited. Redo surgery is sometimes preferable, especially for young patients with a smaller-sized aortic bioprosthesis. With the emergence of TVIV implantation and the long experience of redo valve surgery, we currently have 2 complementary treatment modalities, allowing a tailor-made and patient-orientated intervention. In the heart team, the decision-making should be based on several factors including type of bioprosthesis failure, age, comorbidities, operative risk, anatomical factors, anticipated risks and benefits of each alternative, patient's choice and local experience. The aim of this review is to provide a framework for individualized optimal treatment strategies in patients with failed aortic surgical bioprosthesis.

Right mini-thoracotomy approach reduces hospital stay and transfusion of mitral or tricuspid valve reoperation with non-inferior efficacy: evidence from propensity-matched study

Background

There is limited evidence about the efficacy and cost difference between minimally invasive and conventional valve reoperation. This study intended to compare the short-term efficacy and cost between right mini-thoracotomy approach and median sternotomy approach in valve reoperation.

Methods

From Feb 2011 to Sep 2017, 156 patients underwent valve reoperation including 68 cases of minimally invasive approach and 88 cases of traditional median sternotomy approach in our hospital. A propensity scoring was used to match patients with similar demographic characteristics. A total of 42 pairs of patients were left and divided into the conventional sternotomy group (CS group) and the right mini-thoracotomy group (RT group). A retrospective study of efficacy and cost was conducted between two groups.

Results

There was no statistical difference between two groups in demographical characteristics after propensity-scoring match (P>0.05). In-hospital mortality was 11.9% (5/42) for CS group and 7.1% (3/42) for the RT group (P=0.687). No significant disparity was found in the incidence of complications between two groups (P>0.05). CPB time (P=0.012), bypass time (P=0.006) and operation time (P=0.003) of CS group were significantly higher than RT group. Blood loss (P=0.014) and transfusion volume (P=0.003) of RT group was less than CS group. Shorter ICU and hospital stay was seen in RT group compared with CS group (P<0.001). Though the materials cost of RT group was higher than CS group (P<0.001), no significant disparity was found in total cost between CS group and RT group (P=0.790).

Conclusions

The right mini-thoracotomy approach can achieve equivalent efficacy with conventional median approach, and doesn't necessarily increase the total cost. Moreover, the minimally invasive approach can decrease the operation time, hospital stay and blood product transfusion.

Does the type of cardioplegia used during valve surgery influence operative nadir hematocrit and transfusion requirements?

INTRODUCTION

Myocardial protection is performed using diverse cardioplegic (CP) solutions with various combinations of chemical and blood constituents. Newer CP formulations that extend ischemic intervals may require greater asanguineous volume, contributing to hemodilution.

METHODS

We evaluated intraoperative hemodilution and red blood cell (RBC) transfusion rates among three common CP solutions during cardiac valve surgery. Data from 5,830 adult cardiac primary valve procedures where either four-to-one blood CP (4:1), del Nido solution (DN) or microplegia (MP) was used at 173 United States surgical centers. The primary outcome was the nadir hematocrit (Hct) during cardiopulmonary bypass (CPB), with a secondary outcome of total units of RBC transfused intraoperatively. Outcomes were assessed using mixed-effects regression, with controls for patient size, age, first Hct in the operating room, ultrafiltration volume, net bypass circuit priming volume, anesthesia and perfusion asanguineous volumes, cross-clamp and total procedure times, procedure type, reoperation, hospital, surgeon and twelve other patient and procedural variables.

RESULTS

A total of 2,641 patients received 4:1 (45.3%), 1,864 received DN (32.0%) and 1,325 received MP (22.7%). There were only slight differences in the central tendency (mean (SD)) for crude nadir Hct on CPB: 4:1, 25.5 (4.5), DN, 26.0 (4.6) and MP, 26.5 (4.7). After controlling for numerous operative and patient characteristics, the regression-adjusted estimate of the nadir Hct on CPB for MP was 26.2%, compared to 25.7% for 4:1 and 25.7% for DN; differences between MP and the other methods were statistically significant (p<0.01). Unadjusted mean RBC units transfused per patient was very similar across the groups (4:1, 2.2; MP, 2.3; DN, 2.4). Regression-adjusted estimates for the number of units of RBC transfused intraoperatively showed no statistically significant differences between CP methods.

CONCLUSIONS

In patients undergoing cardiac valve surgery, the type of CP did not have a strong clinical impact on hemodilution or transfusion. Choice of a myocardial preservation solution can be made independently of its effect on intraoperative Hct.

Repeated valve replacement surgery: technical tips and pitfalls

For successful repeated valve replacement surgery, it is essential issue that the preoperative evaluation includes an assessment of the previous operation record, computed tomography (CT: including 3D-CT), ultrasound cardiography, coronary artery angiography, and so on. Although it is especially needed for repeated valve replacement surgery, setting up of the external defibrillation pads is the most important preparation just prior to the surgery. In regard to the approach, re-sternotomy is frequently employed as a standard fashion because it allows us to re-entry any part of the heart. As alternative approaches, partial sternotomy, right thoracotomy for minimally invasive cardiac surgery approach have also been highlighted recently. Myocardial protection is another important consideration in repeated valve replacement surgery, especially in post-coronary artery bypass grafting cases with a patent internal thoracic artery. In repeated valve replacement surgery, special and unique techniques are required both for taking the affected prosthetic valve out and for implanting a new valve, which is dependent on the types of the previous prosthetic valve and the condition of the affected prosthetic valve. Therefore, for performing repeated valve replacement surgeries, surgeons should be highly skilled in these special techniques.