Reoperative minimal access aortic valve surgery: Minimal mediastinal dissection and minimal injury risk

Minimal Access Aortic Valve Surgery

Minimally invasive approaches to the aortic valve have been described since 1993, with great hopes that they would become universal and facilitate day-case cardiac surgery. The literature has shown that these procedures can be undertaken with equivalent mortality rates, similar operative times, comparable costs, and some benefits regarding hospital length of stay. The competing efforts of transcatheter aortic valve implantation for these same outcomes have provided an excellent range of treatment options for patients from cardiology teams. We describe the current state of the art, including technical considerations, caveats, and complications of minimal access aortic surgery and predict future directions in this space.

Aortic valve replacement via a right parasternal approach in a patient with a history of coronary artery bypass surgery and pericardiectomy: a case report

Background

The number of patients who require aortic valve replacement after coronary artery bypass grafting continues to increase. Re-operative cardiovascular surgery after coronary artery bypass grafting has various risk factors related to median re-sternotomy. It is particularly essential to avoid damage to the living graft. We successfully performed aortic valve replacement via right parasternal thoracotomy in a patient who had undergone coronary artery bypass grafting.

Case presentation

An 80-year-old man who had undergone coronary artery bypass grafting was referred to our hospital for syncope caused by severe aortic valve stenosis. He also had a history of pericardiotomy for constrictive pericarditis. His left internal thoracic artery bypass graft was patent. Aortic valve replacement was performed through a small right parasternal thoracotomy during cardiac arrest following cardiopulmonary bypass under moderate hypothermia and hyperkalemia by intermittent selective antegrade cardioplegia. His postoperative course was uneventful.

Conclusion

Aortic valve replacement via right parasternal thoracotomy with moderate hypothermia and hyperkalemia was safe and effective for avoidance of re-sternotomy-related complications.

Efficacy of Aortic Valve Replacement through Full Sternotomy and Minimal Invasion (Ministernotomy)

Background: new minimally invasive sternotomy (mini-sternotomy) procedures have improved the treatment outcome and reduced the incidence of perioperative complications leading to improved patient satisfaction and a reduced cost of aortic valve replacement in comparison to the conventional median sternotomy (full sternotomy). The aim of this study is to compare and gain new insights into operative and early postoperative outcomes, long-term postoperative results, and 5-year survival rates after aortic valve replacement through a ministernotomy and full sternotomy. Methods: This is a retrospective study of patients who underwent an isolated replacement of the aortic valve via a full sternotomy or ministernotomy from 2011 to 2016. From 2011 to 2016, 426 cardiac interventions were performed, 70 of which (16.4%) were of the ministernotomy and 356 (83.6%) of the full sternotomy. Through propensity score matching, 70 patients who underwent the ministernotomy (ministernotomy group) were compared with 70 patients who underwent the full sternotomy (control group). Results: in the propensity matching cohort, no statistical difference in operative time was noted (p = 0.856). The ministernotomy had longer cross clamp (88.7 ± 20.7 vs. 80.3 ± 24.6 min, p = 0.007) and bypass (144.0 ± 29.9 vs. 132.9 ± 44.9 min, p = 0.049) times, less ventilation time (9.7 ± 1.7 vs. 11.7 ± 1.4 h, p < 0.001), shorter hospital stay (18.3 ± 1.9 vs. 21.9 ± 1.9 days, p = 0.012), less 24-h chest tube drainage (256.2 ± 28.6 vs. 407.3 ± 40.37 mL, p < 0.001), fewer corrections of coagulopathy (p < 0.001), fewer patients receiving catecholamine (5.71 vs. 30.0%, p < 0.001) and better cosmetic results (p < 0.001). Moreover, the number of patients without complaints at 1 year after the operation was significantly greater in the ministernotomy group (p = 0.002), and no significant differences in the 5-year survival between the groups were observed. In the overall cohort, the ministernotomy had longer cross clamp times (88.7 ± 20.7 vs. 79.9 ± 24.8 min, p < 0.001), longer operative times (263.5 ± 62.0 vs. 246.7 ± 74.2 min, p = 0.037) and bypass times (144.0 ± 29.9 vs. 132.7 ± 44.5 min, p = 0.026), lower incidence of 30-day mortality (1(1.4) vs. 13(3.7), p = 0.022), shorter hospital stays post-surgery p = 0.025, less 24-h chest tube drainage, p < 0.001, and fewer corrections of coagulopathy (p < 0.001). Conclusions: the ministernotomy has a number of advantages compared with the full sternotomy and thus could be a better approach for aortic valve replacement.

Minimally invasive aortic valve replacement in high risk patient groups

Minimally invasive aortic valve replacement (AVR) aims to preserve the sternal integrity and improve postoperative outcomes. In low risk patients, this technique can be achieved with comparable mortality to the conventional approach and there is evidence of possible reduction in intensive care and hospital length of stay, transfusion requirement, renal dysfunction, improved respiratory function and increased patient satisfaction. In this review, we aim to asses if these benefits can be transferred to the high risk patient groups. We therefore, discuss the available evidence for the following high risk groups: elderly patients, re-operative surgery, poor lung function, pulmonary hypertension, obesity, concomitant procedures and high risk score cohorts.

A Contemporary Approach to Reoperative Aortic Valve Surgery: When is Less, More?

OBJECTIVE

Although the benefits of minimally invasive valvular surgery are well established, the applicability of extending these techniques to reoperative aortic valve surgery is unknown. We evaluated our experience with a minimally invasive approach to this patient population.

METHODS

From January 2010 to September 2015, 21 patients underwent reoperative isolated aortic valve replacement via a minimally invasive approach by a single surgeon. All patients had preoperative evaluation with computerized tomography and coronary catheterization. Surgical approaches were right anterior thoracotomy (6/21) or upper hemisternotomy (15/21). Central aortic cannulation was preferred with femoral artery cannulation used in four patients (19%). In patients with left internal mammary artery (LIMA) grafts, no attempt to dissect or occlude the graft was made. Cold blood cardioplegia was administered antegrade (12/21) or retrograde (9/21); systemic cooling with a mean low temperature of 27.5 °C was employed.

RESULTS

Mean age was 75.1 years with a range from 33 to 92 years, and 67% (14/21) were male. All procedures were completed with a minimally invasive approach. Mean ± SD cross-clamp time was 51.5 ± 9.2 minutes. Fourteen patients had patent LIMA grafts. No aortic, LIMA, or cardiac injuries occurred. There were no hospital deaths nor occurrences of perioperative myocardial infarction, stroke, wound infection, renal failure, or endocarditis/sepsis. One patient required a reoperation for bleeding. Sixty-two percent of patients were discharged to home; mean ± SD length of stay was 6 ± 3 days.

CONCLUSIONS

With appropriate preoperative evaluation and careful surgical planning, a minimally invasive approach to reoperative aortic valve surgery can be performed in a safe and effective manner.

Minimally Invasive Aortic Valve Replacement

With the advent of transcatheter aortic valve replacement and the emergence of rapid deployment aortic valves, there is a resurgent interest in minimizing the trauma of surgical aortic valve replacement (AVR). The present review summarizes the history of minimal access AVR and attempts to collate the existing evidence regarding minimal access AVR.

Minimally invasive aortic valve replacement: Comparison of long-term outcomes

Background

Minimally invasive aortic valve replacement tends to be performed in specialist centers. Little data exists with regard to long-term outcomes of the upper hemi-sternotomy technique. We sought to evaluate the short- and long-term outcomes of this procedure in our institution.

Methods

Data were collected from our cardiac surgical database. We compared the outcomes of all patients who underwent minimally invasive aortic valve replacement with all who underwent conventional aortic valve replacement between July 1999 and December 2013. Propensity-matching analysis was performed to evaluate hospital outcomes.

Results

There were 125 patients who underwent minimally invasive aortic valve replacement and 1446 who had conventional surgery. After propensity score matching, there were no differences in postoperative mortality or complications between the 2 groups. The only significant differences were longer bypass (62.69 ± 10.12 vs. 68.94 ± 14.79 min, p = 0.002) and crossclamp times (45.48 ± 8.08 vs. 52.30 ± 16.29 min, p < 0.001) in conventional surgery. Long-term survival after minimally invasive aortic valve replacement at 2, 6, and 10 years was 88% ± 3.0%, 79% ± 4.0%, and 66% ± 6.0%, respectively. Predictors of long-term survival were age, peripheral vascular disease, and low ejection fraction ( p < 0.005).

Conclusion

Minimally invasive aortic valve replacement has similar hospital outcomes compared to conventional aortic valve replacement. The operation is quicker and does not confer any significant increase in complications or length of hospital stay. The long-term outcomes are favorable and justify its continued use by specialist surgeons in the United Kingdom.

Minimally invasive aortic valve replacement versus aortic valve replacement through full sternotomy: the Brigham and Women's Hospital experience

BACKGROUND

Minimally invasive aortic valve surgery (mini AVR) is a safe and effective treatment option at many hospital centers, but there has not been widespread adoption of the procedure. Critics of mini AVR have called for additional evidence with direct comparison to aortic valve replacement (AVR) via full sternotomy (FS).

METHODS

Our mini AVR approach is through a hemi-sternotomy (HS). We performed a propensity-score matched analysis of all patients undergoing isolated AVR via FS or HS at our institution since 2002, resulting in 552 matched pairs. Baseline characteristics were similar. Operative characteristics, transfusion rates, in-hospital outcomes as well as short and long term survival were compared between groups.

RESULTS

Median cardiopulmonary bypass and cross clamp times were shorter in the HS group: 106 minutes [inter-quartile ranges (IQR) 87-135] vs. 124 minutes (IQR 90-169), P≤0.001, and 76 minutes (IQR 63-97) vs. 80 minutes (IQR 62-114), P≤0.005, respectively. HS patients had shorter ventilation times (median 5.7 hours, IQR 3.5-10.3 vs. 6.3 hours, IQR 3.9-11.2, P≤0.022), shorter intensive care unit stay (median 42 hours, IQR 24-71 vs. 45 hours, IQR 24-87, P≤0.039), and shorter hospital length of stay (median 6 days, IQR 5-8 vs. 7 days, IQR 5-10, P≤0.001) compared with the FS group. Intraoperative transfusions were more common in FS group: 27.9% vs. 20.0%, P≤0.003. No differences were seen in short or long term survival, or time to aortic valve re-intervention.

CONCLUSIONS

Our study confirms the clinical benefits of minimally invasive AVR via HS, which includes decreased transfusion requirements, ventilation times, intensive care unit and hospital length of stay without compromising short and long term survival compared to conventional AVR via FS.

A 16-year experience in minimally invasive aortic valve replacement: context for the changing management of aortic valve disease

OBJECTIVE

The aim of this study was to evaluate short- and long-term morbidity and mortality in patients with aortic valve disease who had minimally invasive aortic valve replacement (AVR) through upper hemisternotomy.

METHODS

From July 1996 to June 2012, a total of 1639 patients underwent minimally invasive aortic valve surgery (AVR). Patient data were extracted from hospital electronic records after institutional review board approval. Outcomes of interest included postoperative complication rates, perioperative mortality, and long-term survival.

RESULTS

The mean age was 67 years (SD, 14 years; range, 22-95 years). Of the total cohort, 211 (13%) underwent reoperative AVR. Postoperatively, 2.3% (37/1639) had reoperations to correct bleeding, 2.7% (44/1639) had strokes, 20.4% (334/1639) had new-onset atrial fibrillation, and 1.5% (24/1639) required permanent pacemakers. Only 34% (571/1639) of the patients received packed red blood cells. The median discharge was on day 6 (5-8), and 72.2% of the patients (1184/1639) were discharged home. Operative mortality was 2.9% (48/1639), and long-term survival at 1, 5, 10, and 15 years was 96%, 93%, 92%, and 92%, respectively. Operative mortality was 5.7% (12/208) for the reoperative patients.

CONCLUSIONS

The upper hemisternotomy approach for AVR is safe and reliable, especially for patients undergoing reoperations and those older than 80 years.

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.

Aortic valve replacement through J-shaped partial upper sternotomy

The introduction of minimally invasive techniques in general surgery, in the late 1980s, influenced cardiac surgery as well. This led to the emergence of several minimal access approaches for aortic valve replacement (AVR). Currently, the upper partial sternotomy with unilateral J-shaped extension to the right through the fourth intercostal space is the most popular minimal access approach. This approach offers the comfort factor of sternotomy, improved cosmetic result, preserved respiratory mechanics, and last but not the least cost saving as no new equipment is required. On the other hand, inability to visualize the whole heart, adequately de-air the left heart, and failure to apply epicardial pacing wires are some of the perceived disadvantages of this approach. This article provides a comprehensive review of the indications, contraindications, technical aspects, outcomes, advantages and disadvantages of AVR through J-shaped partial upper sternotomy.

First-time, isolated surgical aortic valve replacement after prior coronary artery bypass surgery: results from the RECORD multicenter registry

BACKGROUND

This multicenter study was undertaken to determine the immediate and long-term outcomes in patients undergoing a primary surgical aortic valve replacement (AVR) who had a previous coronary artery bypass graft surgery with patent grafts.

METHODS

One hundred and thirteen consecutive patients (mean EuroSCORE II, 10.3 ± 7.7%, median 8.0%) who underwent first-time isolated AVR after coronary artery bypass grafting (CABG) were the subjects of this multicenter study. The procedure was performed through a full sternotomy in 95.7% of cases, a patent internal mammary artery graft was clamped in 76.6% of patients. The temperature of cardioplegia was ≤12 °C in 62.8% of patients and systemic temperature was <32 °C in 23.9% of patients.

RESULTS

Thirty-day mortality was 4.4%. Stroke was observed in 8.0% of patients, low cardiac output syndrome in 14.1%, prolonged tracheal intubation in 20.8%, and intensive care unit stay was longer than five days in 19.5% of patients. Among patients with a patent internal mammary graft (91 patients), clamping of this graft (5.7% vs. 0%, p = 0.57) was associated with a nonsignificant trend toward increased 30-day mortality. One-, three- and five-year survival rates were 91.5%, 90.4%, and 88.4%, respectively.

CONCLUSIONS

Patients undergoing isolated AVR after prior CABG have a good immediate and late survival. A history of prior CABG should not be considered an absolute indication for transcatheter AVR.

Reoperative minimal access aortic valve replacement

Reoperative minimal access aortic valve replacement (AVR) is performed through an upper hemisternotomy with peripheral cannulation. This approach limits dissection of mediastinum and especially the left internal mammary artery (LIMA) graft in patients with previous coronary artery bypass grafting (CABG) thus minimizing trauma to the patient. This approach is safe and feasible and may have some benefit over conventional full sternotomy in terms of mortality and morbidity.

Aortic valve replacement after previous coronary artery bypass grafting: a case report

We experienced a case of aortic valve replacement after previous coronary artery bypass grafting with patent bypass grafts. Based on the retrosternal anatomy assessed by preoperative angiography and thoracic computed tomography, aortic valve replacement was performed through a median resternotomy. After careful dissection of the right side of the heart and the ascending aorta, cardiopulmonary bypass was established with cannulation of the ascending aorta and bicaval venous cannulation. The patent bypass grafts were dissected only as required for clamping and were clamped during cardiac arrest. After aortic valve replacement, the patient was uneventfully weaned from cardiopulmonary bypass and had a good postoperative recovery. It is important that surgeons have a meticulous strategy for reducing the risks associated with operating on patients with patent bypass grafts. We report on the surgical management of patients undergoing aortic valve replacement after previous coronary artery bypass grafting, including careful planning during the first operation.

Minimal-access aortic valve replacement with concomitant aortic procedure: a 9-year experience

OBJECTIVE

Minimal-access approaches through upper hemisternotomy is an established technique for aortic valve replacement (AVR) and aortic surgery in our institution. We assessed the outcome of undergoing AVR with concomitant aortic surgery through upper hemisternotomy.

METHODS

We retrospectively reviewed 109 patients from January 2002 to May 2011 who had AVR with concomitant aortic surgery through upper hemisternotomy. Aortic valve replacement with supracoronary ascending aortic replacement was performed in 65 patients; AVR with ascending and proximal arch replacement, in 8 patients; AVR with aortoplasty, in 11 patients; Bentall procedure, in 8 patients; and AVR with root enlargement, in 13 patients. In-hospital outcomes and 1- and 5-year survival were examined.

RESULTS

The mean age was 58.5 years (range, 23-89 years); 41.3% of patients had bicuspid aortic valve (n = 45). Of the patients, 82.6% had true aneurysm (n = 90), 2.8% had calcified aorta (n = 3), 8.3% had small annulus (n = 9), and 3.7% had calcified annulus (n = 4). There were 6 (5.5%) reoperations and 15 (13.8%) urgent cases. Mean perfusion time was 152 ± 61 minutes, and cross-clamp time was 108 ± 47 minutes. Nine cases were performed with deep hypothermic circulatory arrest (8.3%). Operative mortality was 2.8% (n = 3). There were 4 (3.7%) cases with reoperation for bleeding, 2 (1.8%) myocardial infarctions, and 2 (1.8%) new-onset renal failure. Mean length of stay was 7.1 ± 5.6 days. Kaplan-Meier analysis showed that 1-year postoperative survival was 96.2% and 5-year survival was 92.4%.

CONCLUSIONS

An upper hemisternotomy approach is safe and feasible for AVR and concomitant aortic surgery with good early and midterm outcomes. This approach is also associated with low morbidity rate and short length of stay.

Clinical results of minimally invasive mitral valve surgery: endoaortic clamp versus external aortic clamp techniques

OBJECTIVE

: This study was carried out with the aim of presenting our experience with minimally invasive mitral surgery and compare the endoaortic clamp with the external aortic clamp (EAC) techniques.

METHODS

: Between December 2002 and May 2009, 139 patients (75 men, aged 63 ± 11 years) underwent video-assisted mitral valve surgery through right thoracotomy. Twelve (9%) patients were operated without clamping the aorta, 32 (23%) patients (group A) were operated on by using the endoaortic clamp, and 95 (68%) patients were operated on by using the EAC (group B). There was no significant difference between groups A and B regarding preoperative variables.

RESULTS

: Intraoperative procedure-associated problems were experienced in three group A patients (9.3%, two aortic dissections with conversion to sternotomy; one conversion due to bad exposure) and in two group B patients (2%, one conversion to sternotomy for bleeding and one for ascending aorta hematoma). At a mean follow-up of 32 months, 121 patients (97%) were in New York Heart Association class I-II, with satisfactory echocardiographic results. There was one in-hospital and six late deaths (three noncardiac, two cardiac, and one valve related). Five-year actuarial survival was 88% ± 8%. There were three reoperations, one early (<30 days) after complex mitral valve repair, with a 5-year freedom from reoperation of 97% ± 2%. Postoperative levels of myocardial cytonecrosis enzymes as well as the extracorporeal circulation time were significantly lower in group B patients (P < 0.05).

CONCLUSIONS

: Intraoperative procedure-associated complications with endoclamping combined with an apparently better myocardial protection forced us to change our practice to the more simple and economic EAC technique.

Is a minimally invasive approach for re-operative aortic valve replacement superior to standard full resternotomy?

A best-evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'is a minimally invasive approach for re-operative aortic valve replacement (AVR) superior to standard full resternotomy?' A total of 193 papers were found using the reported search of which 13 represented the best evidence to answer the clinical question. The authors, country, journal and date of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that minimally invasive re-operative AVR can be performed with an operative morbidity and mortality at least similar to the standard full sternotomy approach. A shorter hospital length of stay and less blood product requirements are the main advantages of this technique. The incidence of prolonged ventilation, bleeding requiring re-operation, sternal wound infections and in-hospital mortality may be reduced with a minimally invasive approach. Prospective studies are required to confirm the potential benefits of minimally invasive surgery and, up to date, conventional full re-sternotomy is still the standard approach for re-operative AVR.

Minimally invasive surgery for aortic stenosis in the geriatric patient: where are we now?

Minimally invasive aortic valve surgery has evolved with time and become the routine approach for aortic surgery in select surgical centers. The success of these procedures in the nonelderly has led some to embark on using minimal access techniques in the geriatric population as well. With the geriatric community often inflicted with the greatest disease burden, suffering not only from a valvular process but also cumulative comorbidities, geriatric patients may be the patients most likely to derive benefit from a minimally invasive approach. Alternative therapies for symptomatic aortic stenosis include conventional full-sternotomy aortic valve replacement in addition to transcatheter aortic valve implantation. Each option has its advantages and disadvantages. The role of minimal access aortic valve surgery and its impact on the progressively aging population in the face of conventional surgery and transcatheter technology is discussed.

Surgical Approaches to Aortic Valve Replacement and Repair-Insights and Challenges

Since 1960, surgical aortic valve replacement (sAVR) had been the only effective treatment for symptomatic severe aortic stenosis until the recent development of transcatheter aortic valve replacement (TAVR). TAVR has offered an alternative, minimally invasive treatment approach particularly for patients whose age or co-morbidities make them unsuitable for sAVR. The rapid and enthusiastic utilization of this new technique has triggered some speculation about the imminent demise of sAVR. We believe that despite the recent advances in TAVR, surgical approach to aortic valve replacement has continued to develop and will continue to be highly relevant in the future. This article will discuss the recent developments and current approaches for sAVR, and how these approaches will keep pace with catheter-based technologies.

Systemic hyperkalemia and mild hypothermia for valve surgery in patients with patent internal mammary artery graft

Myocardial protection is compromised in patients with a patent internal mammary artery (IMA) graft. We assessed the advantages of systemic hyperkalemia with mild hypothermia for valve surgery in patients with a patent IMA graft. Nine patients (mean age 71.5+/-7.0 years) with a patent IMA graft underwent valve surgery from May 2004 to July 2009. Of those, eight underwent aortic valve replacement and one mitral repair, with two double-valve surgery. Antegrade and retrograde blood cardioplegia were performed intermittently, and systemic potassium was given to all. The lowest bladder temperature was 27.2+/-2.4 degrees C, and the initial and peak systemic potassium levels were 6.8+/-1.4 and 8.0+/-1.6 mEq/l, respectively, while potassium at the end of the cardiopulmonary bypass procedure after sufficient modified ultrafiltration was reduced to 5.5+/-0.6 mEq/l. There was one hospital death due to ischemic colitis. Cardiac arrest was easily achieved in each patient without IMA or aortocoronary graft injury. The postoperative peak creatine kinase-MB level was 33+/-17 IU/l, with no ST changes seen in electrocardiogram findings or new asynergy seen in echocardiogram findings. Systemic hyperkalemia and mild hypothermia for valve surgery in patients with a patent IMA graft is a good option to reduce graft and myocardial injuries.

Outcomes of reoperative aortic valve replacement after previous sternotomy

OBJECTIVE

Increasingly, patients with previous sternotomy require aortic valve replacement. We compared outcomes of reoperative aortic valve replacement after previous sternotomy and primary aortic valve replacement by surgical era. Effect of initial cardiac operation on reoperative aortic valve replacement was also investigated.

METHODS

Between January 1996 and December 2007, a total of 1603 patients undergoing elective aortic valve replacement were entered prospectively into our clinical database. Patients were divided into eras A (1996-1999), B (2000-2003), and C (2004-2007). A total of 191 patients (12%) had previous sternotomy for coronary artery bypass grafting (n = 88), coronary artery bypass grafting with aortic valve replacement (n = 16), aortic valve replacement with or without other aortic procedure (n = 70), and other cardiac procedures (n = 17). Mean ages were 66.5 +/- 13.1 years in reoperative group and 65.5 +/- 14.9 years in primary group.

RESULTS

Mortality in reoperative group decreased significantly with time (A 15.4% vs B 15.1% vs C 2.0%, P = .004) and was equivalent to primary group in era C (3.5% vs 2.0%, P = .65). Major complications also significantly decreased with time in reoperative group (A 25.6% vs B 17.0% vs C 6.1%, P = .006). Importantly, patients had more comorbidities with time and increased preoperative risk in era C. There were no differences in outcome by initial cardiac operation in reoperative group.

CONCLUSIONS

Reoperative aortic valve replacement now carries similar morbidity and mortality to primary replacement. Risk of reoperation is not affected by primary operation.