Decade of aortic valve sparing reimplantation: are we pushing the limits too far?

Treatment of the aortic root in acute aortic dissection type A: insights from the German Registry for Acute Aortic Dissection Type A

OBJECTIVES

Surgery of the aortic root in acute aortic dissection type A (AADA) remains a topic of vague evidence since the extend of dissection and surgeons' capability and interpretation of the disease vary remarkably. We aimed to interpret root operation strategies in the German Registry for Acute Aortic Dissection cohort.

METHODS

German Registry for Acute Aortic Dissection collected the data of 56 centres between July 2006 and June 2015. A total of 3382 patients undergoing operations for AADA were included and divided into 3 groups according to aortic root procedure types: supracommissural replacement (SCR), conduit replacement (CR) and valve sparing root replacement (VSRR).

RESULTS

Patients in SCR (2425, 71.7%) were significantly older than CR (681, 20.1%) and VSRR (276, 8.2%) (63.4 vs 57.5 vs 54.2 years; P < 0.001), more female (38.9% vs 32.0% vs 26.1%; P < 0.001) and presented with less aortic regurgitation (26.3% vs 57.1% vs 56.5%; P < 0.001). VSRR presented with slightly less multiple organ malperfusion (11.6% vs 12.0% vs 10.9%; P = 0.045) and were more often diagnosed for Marfan syndrome (2.4% vs 5.1% vs 9.1%; P < 0.001). Thirty-day mortality was lower for VSRR (11.6%) compared to SCR (16.1%) and CR (19.8%; P = 0.010). Despite longer procedural times, multivariable regression showed no influence of total arch replacement for VSRR on mortality compared to CR (odds ratio 0.264; 95% confidence interval, 0.033-2.117; P = 0.21).

CONCLUSIONS

SCR remains the procedure of choice in elderly and compromised patients. Extended root preservation techniques may be applied even in combination with extended aortic arch surgery for selected patients for AADA with promising early outcomes.

Early and long-term results of aortic valve sparing aortic root reimplantation surgery for bicuspid and tricuspid aortic valves

Introduction:

To evaluate early and long-term clinical outcomes following aortic valve sparing aortic root reimplantation surgery in patients with leaking bicuspid and tricuspid aortic valves.

Methods:

The study consisted of 92 consecutive adult patients (tricuspid aortic valve group = 63 and bicuspid aortic valve group = 29) who underwent aortic valve sparing aortic root reimplantation surgery with or without aortic cusp repair for dilatation of the aortic root and/or aortic valve regurgitation at our institution from April 2004 to October 2016. Clinical outcomes were investigated using Kaplan–Meier and log-rank tests between groups.

Results:

The follow-up was 100% complete with a mean time of 5.3 ± 3.3 years. The 30-day in-hospital mortality was 3.1% in tricuspid aortic valve group and 3.4% in bicuspid aortic valve group patients. The overall survival rates at 10 years did not differ between bicuspid aortic valve and tricuspid aortic valve patient groups (96.6 ± 3.3% vs. 90.3 ± 4.2%, p = 0.3). Freedom from recurrent aortic valve regurgitation (>2+) at 10 years was 90.5 ± 4.1% in tricuspid aortic valve group and 75.7 ± 8.7% in bicuspid aortic valve group (p = 0.06). Freedom from aortic valve reoperation at 10 years was 100% in tricuspid aortic valve group and 83.9 ± 7.4% in bicuspid aortic valve group (p = 0.002).

Conclusion:

Aortic valve sparing aortic root reimplantation surgery is a safe and efficient technique, providing acceptable long-term survival with low rates of valve-related complications in both tricuspid aortic valve and bicuspid aortic valve patient groups. However, aortic valve reoperation rates at 10 years follow-up were higher in bicuspid aortic valve group patients compared to tricuspid aortic valve group patients.

Biological solutions to aortic root replacement: valve-sparing versus bioprosthetic conduit‡

OBJECTIVES

Valve-sparing operations and root replacement with a biologic composite conduit are viable options in aortic root aneurysm. This study was conceived to compare the early and mid-term results of these 2 procedures.

METHODS

From September 2002 to November 2015, 749 consecutive patients underwent either a valve-sparing operation or a root replacement with a biologic composite conduit at 2 institutions. Propensity score matching was used to compare similar cohorts of patients in the overall population and in the ≤ 55 and ≥ 65-year age groups.

RESULTS

Overall operative mortality was 0.4%, mean age 57.4 ± 14.3 years, 84.6% were male. Individuals in the biologic composite conduit group were older and had worse preoperative risk profiles [chronic pulmonary disease (5.5% vs 0.9%; P  = 0.001), diabetes (6.4% vs 1.5%; P  = 0.001) and NYHA > 2 (25.2% vs 5.2%; P  < 0.001)]. Mean follow-up was 27.5 ± 28.4 months. In the unmatched population, there was no difference in in-hospital deaths (0 in the valve-sparing versus 3 in the biologic composite conduit group; P  = 0.12). These findings were confirmed in the propensity-matched populations. During follow-up, more patients in the biologic composite conduit group underwent reoperation on the aortic valve (2.6% vs 1.5%; P  = 0.026) resulting in a freedom from reoperation of 97.4% vs 98.5%, respectively. Separate analysis for patients stratified by age revealed no difference in outcomes.

CONCLUSIONS

In case of aortic root aneurysm, both valve-sparing operations and root replacement with a biologic composite conduit provide excellent outcomes. However, at mid-term follow-up the use of biologic composite conduit is associated with a higher risk of reoperation.

Surgical Treatment of Annuloaortic Ectasia - Replace or Repair?

Background

Patients with annuloaortic ectasia may be surgically treated with modified Bentall or David I valve-sparing procedures. Here, we compared the long-term results of these procedures.

Methods

A total of 181 patients with annuloaortic ectasia underwent modified Bentall (102 patients, Group 1) or David I (79 patients, Group 2) procedures from 1994 to 2015. Mean age was 62 ± 11 years in Group 1 and 64 ± 16 years in Group 2. Group 1 patients were in poorer health, with a lower ejection fraction and higher functional class.

Results

Early mortality was 3% in Group 1 and 2.5% in Group 2. Patients undergoing a modified Bentall procedure had a higher incidence of thromboembolism and hemorrhage, whereas those undergoing a David I procedure had a higher incidence of endocarditis. Actuarial survival was 70 ± 6% at 15 years in Group 1 and 84 ± 7% at 10 years in Group 2. Actuarial freedom from reoperation was 97 ± 2% at 15 years in Group 1 and 84 ± 7% at 10 years in Group 2. In Group 2, freedom from procedure-related reoperations was 98 ± 2% at 10 years. At last follow-up, no cases of moderate or severe aortic regurgitation were observed.

Conclusions

The modified Bentall and David I procedures showed excellent early and late results. The modified Bentall procedure with a mechanical conduit was associated with thromboembolic and hemorrhagic complications, whereas the David I procedure was associated with unexplained occurrences of endocarditis. Thus, the David I procedure appears to be safe, reproducible, and capable of achieving stable aortic valve repair and is therefore our currently preferred solution for patients with annuloaortic ectasia. However, the much shorter follow-up for David I patients limits the strength of our comparison between the two techniques.

The influence of Marfans and bicuspid valves on outcomes following aortic valve reimplantation

BACKGROUND

We analyzed our early and midterm results with aortic valve reimplantation surgery to determine the influence of Marfan syndrome and bicuspid valves on outcomes with this technique.

METHODS

Between March 2004 and December 2015, 267 patients underwent aortic valve reimplantation operations. The mean diameter of the sinuses of Valsalva was 50 ± 3 mm and moderate/severe aortic regurgitation was present in 34.4% of these patients. A bicuspid aortic valve was present in 21% and 40% had Marfan syndrome.

RESULTS

Overall 30-day mortality was 0.37% (1/267). Mean follow-up was 59.7 ± 38.7 months. Overall survival at 1, 3, and 5 years was 98 ± 8%, 98 ± 1%, and 94 ± 2%, respectively. Freedom from reoperation and aortic regurgitation >II was 99 ± 5%, 98 ± 8%, 96.7 ± 8%, and 99 ± 6%, 98 ± 1%, 98 ± 1%, respectively at 1, 3, and 5 years follow-up, with no differences between Marfan and bicuspid aortic valve groups. (p = 0.94 and p = 0.96, respectively). No endocarditis or thromboembolic complications were documented, and 93.6% of the patients did not receive any anticoagulation therapy.

CONCLUSIONS

The reimplantation technique for aortic root aneurysms is associated with excellent clinical and functional outcomes at short and mid-term follow-up.

AP-1 Oligodeoxynucleotides Reduce Aortic Elastolysis in a Murine Model of Marfan Syndrome

Marfan syndrome is characterized by high expression of matrix metalloproteinases (MMPs) in aortic smooth muscle cells (AoSMCs) associated with medial elastolysis and aortic root aneurysm. We aimed to reduce aortic elastolysis through decrease of MMP expression with decoy oligodeoxynucleotides (dODNs) neutralizing the transcription factor activating factor-1 (AP-1). AP-1 abundance in nuclear extracts as well as MMP-2 and MMP-9 expression were significantly increased in isolated mAoSMC of mgR/mgR Marfan mice compared to wild-type cells. Exposure to AP-1 neutralizing dODNs resulted in a significant reduction of basal and interleukin-1β-stimulated MMP expression and activity in mAoSMCs. Moreover, increased migration and formation of superoxide radical anions was substantially decreased in mAoSMCs by AP-1 dODN treatment. Aortic grafts from donor Marfan mice were treated with AP-1- dODN ex vivo and implanted as infrarenal aortic interposition grafts in mgR/mgR mice. Pretreatment of aortic grafts with AP-1 dODN led to reduced elastolysis, macrophage infiltration, and MMP activity. Permeability of the endothelial monolayer was increased for dODN in mgR/mgR aortae with observed loss of tight junction proteins ZO-1 and occludin, enabling dODN to reach the tunica media. Targeting AP-1 activity offers a new potential strategy to treat the vascular phenotype associated with Marfan syndrome.

Partial aortic root remodeling for root reconstruction in patients with acute type A dissection

In the present study, we reported our experience with partial aortic root remodeling for root reconstruction in patients with acute type A dissection, which involves in non-coronary sinus and/or the right coronary sinus with just one trimmed Dacron graft. Between February 2001 and May 2010, we performed partial aortic root remodeling in 40 patients, who underwent emergency surgical intervention. The dissected sinuses were excised leaving a 3-5 mm rim of the aortic wall from the attached aortic valve cusps. A short piece (4-5 cm) of collagen coated woven polyester vascular prosthesis was trimmed with one or two “tongues” to reconstruct the non-coronary sinus and/or the right coronary sinus, but without using separated patches. Additional procedures were including hemi-arch replacement in 11 patients, and total arch replacement plus stent-elephant trunk in 20 patients. The mean follow-up time was 36.4±3.6 months. In-hospital mortality was only 5.0% (2/40); furthermore, 3 (8.6%) patients underwent re-operation of the aortic valve and 2 (5.7%) patients died during follow-up. At the end of follow-up, trivial or no aortic regurgitation was found in 33 patients, but mild aortic regurgitation was found in 2 patients. Our data suggest that the early and mid-term results of partial aortic root remodeling were favorable, and it restored valve durability and function. Thus, the use of technique for root reconstruction in patients with acute type A dissection should be vigorously encouraged.

Minimally invasive valve sparing aortic root replacement (David procedure) is safe

OBJECTIVE

Even though minimally invasive cardiac surgery may reduce morbidity, this approach is not routinely performed for aortic root replacements. The purpose of this pilot study was to assess the safety and feasibility of valve sparing aortic root replacement via an upper mini-sternotomy up to the 3(rd) intercostal space.

METHODS

Between April 2011 and March 2014, 26 patients (22 males, age 47.6±13 years) underwent elective minimally invasive aortic valve sparing root replacement (David procedure, group A). Twelve patients underwent additional leaflet repair. Concomitant procedures were: four proximal aortic arch replacements and one coronary artery bypass grafting (CABG) to the proximal right coronary artery (RCA). During the same time period, 14 patients (ten males, age 64.2±9.5 years) underwent elective David procedure via median full sternotomy (group B). Concomitant procedures included six proximal aortic arch replacements. Although the patient cohorts were small, the results of these two groups were compared.

RESULTS

In group A, there were no intra-operative conversions to full sternotomy. The aortic cross-clamp and cardiopulmonary bypass (CPB) times were 115.6±30.3 and 175.8±41.9 min, respectively. One patient was re-opened (via same access) due to post-operative bleeding. The post-operative ventilation time and hospital stay were 0.5±0.3 and 10.4±6.8 days, respectively. There was no 30-day mortality. The patient questionnaire showed that the convalescence time was approximately two weeks. In group B: the cross-clamp and CPB times were 114.1±19.9 and 163.0±24.5 min, respectively. One patient was re-opened (7.1%) due to post-operative bleeding. The post-operative ventilation time and hospital stay were 0.6±0.7 and 14.2±16.7 days, respectively. There was no 30-day mortality.

CONCLUSIONS

Minimally invasive valve sparing aortic root replacement can be safely performed in selected patients. The results are comparable to those operated via a full sternotomy. The key to success is a 'step by step' technique of moving from minimally invasive aortic valve replacements (AVR) to more demanding aortic root replacements. Meticulous hemostasis & attention to surgical details is of utmost importance to prevent perioperative complications.

The ascending aortic aneurysm: When to intervene?

Background

Thoracic ascending aorta aneurysms (TAA) are an important cause of mortality in adults but are a relatively less studied subject compared to abdominal aortic aneurysms (AAA). The purpose of this review is to explain the main aspects (etiology, pathophysiology, diagnosis) of this disease and to summarize the most recent developments in its management.

Methodology

Literature was obtained through online health related search engines (PubMed, MEDLINE) by including the following keywords: ascending aorta aneurysm, thoracic aneurysms, Marfan syndrome, bicuspid aortic valve, familial thoracic syndrome, aortic dissection, aorta imaging and aortic aneurysm guidelines. We included articles dating from 1980 to 2014.

Findings

Literature revealed how lethal this disease can be and how simple steps such as follow-up and prophylactic surgery can significantly reduce morbidity and mortality. This review also allowed us to realize the many developments that have been made in recent years in the understanding of pathologic mechanisms of this disease.

Conclusion

TAA is a silent disease that needs to be recognized early in its course and followed closely in order to recommend appropriate preventive and prophylactic therapy in a timely manner.

Systematic review of aortic valve preservation and repair

BACKGROUND

Aortic valve repair has emerged as a feasible alternative to replacement in the surgical treatment of selected patients with aortic valve (AV) pathology. In order to provide a synopsis of the current literature, we preformed a systematic review with a focus on valve-related events following AV repair.

METHODS

Structured keyword searches of Embase and PubMed were performed in January 2012. A study was eligible for inclusion if it reported early mortality, late mortality, or valve-related morbidity in the adult population.

RESULTS

Initial search results identified 3,507 unique studies. After applying inclusion and exclusion criteria, 111 studies remained for full-text review. Of these, 17 studies involving 2,891 patients were included for quantitative assessment. No randomized trials were identified. Tricuspid and bicuspid AV pathologies were present in 65% (range, 21-100%) and 13.5% (range, 5-100%) of the population, respectively. Cusp repair techniques were applied in a median of 46% (range, 5-100%) of patients. The median requirement for early reoperation for post-operative bleeding and early reintervention for primary AV repair failure was 3% (range, 0-10%) and 2% (range, 0-16%), respectively. Pooled early mortality was 2.6% (95% CI: 1.4-4.4%, I(2) =0%). Late mortality and valve-related events were linearized [(number of events/number of patient-years) ×100] (%/pt-yr) for each study. Late operated valve endocarditis was reported at median event rate of 0.23%/pt-yr (range, 0-0.78%/pt-yr), while a composite outcome of neurological events and thromboembolism occurred at a median rate of 0.52%/pt-yr (0-0.95%/pt-yr). Late AV re-intervention requiring AV replacement or re-repair occurred at a rate of 2.4%/pt-yr (range, 0-4.2%/pt-yr). The median 5-year freedom from AV re-intervention and late recurrent aortic insufficiency >2+ estimated from survival curves was 92% (range, 87-98%) and 88% (range, 87-100%), respectively. Pooled late mortality produced summary estimate of 1.3%/pt-yr (95% CI: 0.9-2.1%, I(2) =0%).

CONCLUSIONS

The present systematic review confirmed the low operative risk of patients who underwent aortic valve preservation and repair. There is a need for long-term follow-up studies with meticulous reporting of outcomes following AV repair, as well as comparative studies with aortic valve replacement.

David valve-sparing aortic root replacement: equivalent mid-term outcome for different valve types with or without connective tissue disorder

OBJECTIVE

Although implicitly accepted by many that the durability of valve-sparing aortic root replacement in patients with bicuspid aortic valve disease and connective tissue disorders will be inferior, this hypothesis has not been rigorously investigated.

METHODS

From 1993 to 2009, 233 patients (27% bicuspid aortic valve, 40% Marfan syndrome) underwent Tirone David valve-sparing aortic root replacement. Follow-up averaged 4.7 ± 3.3 years (1102 patient-years). Freedom from adverse outcomes was determined using log-rank calculations.

RESULTS

Survival at 5 and 10 years was 98.7% ± 0.7% and 93.5% ± 5.1%, respectively. Freedom from reoperation (all causes) on the aortic root was 92.2% ± 3.6% at 10 years; 3 reoperations were aortic valve replacement owing to structural valve deterioration. Freedom from structural valve deterioration at 10 years was 96.1% ± 2.1%. No significant differences were found in survival (P = .805, P = .793, respectively), reoperation (P = .179, P = .973, respectively), structural valve deterioration (P = .639, P = .982, respectively), or any other functional or clinical endpoints when patients were stratified by valve type (tricuspid aortic valve vs bicuspid aortic valve) or associated connective tissue disorder. At the latest echocardiographic follow-up (95% complete), 202 patients (94.8%) had none or trace aortic regurgitation, 10 (4.7%) mild, 0 had moderate to severe, and 1 (0.5%) had severe aortic regurgitation. Freedom from greater than 2+ aortic regurgitation at 10 years was 95.3% ± 2.5%. Six patients sustained acute type B aortic dissection (freedom at 10 years, 90.4% ± 5.0%).

CONCLUSIONS

Tirone David reimplantation valve-sparing aortic root replacement in carefully selected young patients was associated with excellent clinical and echocardiographic outcome in patients with either a tricuspid aortic valve or bicuspid aortic valve. No demonstrable adverse influence was found for Marfan syndrome or connective tissue disorder on durability, clinical outcome, or echocardiographic results.

Long-term results after aortic valve-sparing operation (David I)

OBJECTIVE

Aortic valve-sparing David procedure has gained broad acceptance. However, few long-term results have been published. We present our results.

METHODS

More than 450 David procedures have been performed in our institution so far. Of these, 126 patients were operated between July 1993 and December 2000. Median age was 57 (8-83) years and 46 (36.5%) were female. As many as 26 (20.6%) had Marfan syndrome, 21 (16.7%) had acute aortic dissection type A (AADA) and 67 (53.2%) had additional procedures.

RESULTS

There were six (4.8%) deaths in 30 post-operative period (POD), four of whom had AADA. In the follow-up, there were 32 (25.4%) late deaths, 11 (34.4%) of these were caused by cardiac or underlying disease or op-related. As many as 15 (11.9%) patients were re-operated; six (40%) were Marfan patients and two (13.3%) had early endocarditis. Follow-up echocardiography of 76 (60.3%) event-free patients showed valve insufficiency (AI)≤AI I° in 68 (89.5%) and grade II in 7 (9.2%) patients. Leaflet degeneration due to proposed leaflet contact with the straight Dacron graft was not observed. A total of 36 (47.4%) patients were in New York Heart Association (NYHA) class I, 33 (43.4%) in NYHA II, and five (6.6%) were in class III. During the entire follow-up of 790 patient-years, there was no stroke or major bleeding. Survival at 1, 5 and 10 years was 93%, 85% and 70%, respectively. Freedom from valve replacement at 1, 5 and 10 years was 96%, 91% and 87%, respectively.

CONCLUSIONS

Regardless of the underlying pathology, valve-sparing David I procedure has acceptable long-term results. Valve-related complications such as stroke or major bleeding is exceedingly low.

[Modern aortic surgery in Marfan syndrome--2011]

Marfan syndrome is a hereditary disease with a prevalence of 2-3 in 10,000 births, leading to a fibrillin connective tissue disorder with manifestations in the skeleton, eye, skin, dura mater and in particular the cardiovascular system. Since other syndromes demonstrate similar vascular manifestations, but therapy may differ significantly, diagnosis should be established using the revised Ghent nosology in combination with genotypic analysis in specialized Marfan centres. The formation of aortic root aneurysms with the subsequent risk of acute aortic dissection type A (AADA) or aortic rupture limits life expectancy in patients with Marfan syndrome. Therefore, prophylactic replacement of the aortic root needs to be performed before the catastrophic event of AADA can occur. The goal of surgery is the complete resection of pathological aortic tissue. This can be achieved with excellent results by using a (mechanically) valved conduit that replaces both the aortic valve and the aortic root (Bentall operation). However, the need for lifelong anticoagulation with Coumadin can be avoided using the aortic valve sparing reimplantation technique according to David. The long-term durability of the reconstructed valve is favourable, and further technical improvements may improve longevity. Although results of prospective randomised long-term studies comparing surgical techniques are lacking, the David operation has become the surgical method of choice for aortic root aneurysms, not only at the Heidelberg Marfan Centre. Replacement of the aneurysmal dilated aortic arch is performed under moderate hypothermic circulatory arrest combined with antegrade cerebral perfusion using a heart-lung machine, which we also use in thoracic or thoracoabdominal aneurysms. Close post-operative follow-up in a Marfan centre is pivotal for the early detection of pathological changes on the diseased aorta.

Bicuspidy does not affect reoperation risk following aortic valve reimplantation

Aortic valve reimplantation has been shown to be a safe procedure. However, evidences of durability in bicuspid aortic valves (BAVs) are limited in the literature. Between 2002 and 2011, 132 patients (mean age 61 ± 12 years) underwent aortic valve reimplantation. In 24 patients (18%), aortic valve was bicuspid. Mean follow-up was 50 ± 26 months (range 1-102 months) and was 99% complete. In-hospital mortality was 0.8% (1 patient). Survival at 1 and 5 years was 99 and 94%, respectively. Overall freedom from aortic valve reoperation at 1 and 5 years was 96 and 90%, respectively, without significant difference between patients with bicuspid and tricuspid aortic valve. Freedom from aortic valve regurgitation >2+/4+, excluding patients reoperated, was at 1 and 5 years of 100 and 99%, respectively. Patients with valve cusp repair showed a higher rate of aortic valve reoperation; however, only postoperative aortic regurgitation >2+/4+ was significant risk factor for redo procedure at multivariate analysis. Aortic valve reimplantation in BAV without cusp repair provides excellent mid-term results. Further observations and longer follow-up are necessary to determine if BAV sparing, even in the presence of cusps alterations, could allow satisfying durability.

Expanding the indications for the David V aortic root replacement: early results

OBJECTIVE

To examine the early results of the David V valve-sparing aortic root replacement procedure in expanded, higher risk clinical scenarios with appropriately selected patients.

METHODS

From 2005 to 2011, 150 David V valve-sparing aortic root replacements were performed within Emory Healthcare. A total of 78 patients (expanded group) had undergone the David V in expanded, difficult clinical settings such as emergent type A dissection (n = 29), grade 3+ or greater aortic insufficiency (AI) (n = 53), or reoperative cardiac surgery (n = 14). These patients were evaluated and compared with a group of 72 patients (traditional group) with less than grade 3+ AI who underwent a David V in a traditional, elective setting. The mean follow-up was 19 months (range, 1-72), and the follow-up data were 88% complete.

RESULTS

There were 3 operative deaths (2.2%), all occurring in the expanded group. The overall patient survival at 6 years was 95%. Three patients required aortic valve replacement: two for severe AI and one for fungal endocarditis. Both groups had concomitant cusp repairs performed in conjunction with the David V (traditional, n = 10; and expanded, n = 16; P = .27). At follow-up, freedom from moderate AI was 93%, and the freedom from aortic valve replacement was 98%. No significant difference was observed in the freedom from moderate AI between the expanded and traditional groups (91% vs 95%, respectively; P = .16).

CONCLUSIONS

In selected patients possessing appropriate aortic cusp anatomy, the David V can be safely and effectively performed for the expanded indications of aortic dissection, severe AI, and reoperative cardiac surgery with low operative risk. Valve function has remained excellent in the short term, providing evidence of durability and a low rate of valve-related complications.

Aortic root surgery in septuagenarians: impact of different surgical techniques

Background

To evaluate the impact and safety of different surgical techniques for aortic root replacement (ARR) on early and late morbidity and mortality in septuagenarians undergoing ARR.

Methods

Ninety-five patients (73.8 ± 3.2 years) were operated and divided into three groups according to the aortic root procedure; MECH-group (n = 51) patients with a mechanical composite graft, BIO-group (n = 22) patients with a customized biological composite graft, and REIMPL-group (n = 22) patients with a valve sparing aortic root reimplantation (David I). In 42.1% (40/95) of these patients the aortic arch was replaced. Follow-up was completed in 95.2% (79/83) of in-hospital survivors.

Results

Hospital mortality was 12.6% (12/95) in the entire population (MECH. 15.7% (8/51), BIO 19.7% (4/22), REIMPL 0% (0/22); p = 0.004). Two patients died intraoperatively. The most frequent postoperative complications were prolonged mechanical ventilation ((>48 h) in 16.8% (16/93) (MECH. 7% (7/51), BIO 36.4% (8/22), REIMPL 4.5% (1/22); p = 0.013) and rethoracotomy for postoperative bleeding in 12.6% (12/95) (MECH. 12% (6/51), BIO 22.7% (5/22), REIMPL 4.5% (1/22); p = 0.19). Nineteen late deaths (22.9%) (19/83) (MECH 34.8% (15/43), BIO 16.7% (3/18), REIMPL 4.5% (1/22); p = 0.012) occurred during a mean follow-up of 41 ± 42 months (MECH 48 ± 48 months, BIO 25 ± 37 months, REIMPL 40 ± 28 months, p = 0.028). Postoperative NYHA class decreased significantly (p = 0.017) and performance status (p = 0.027) increased for the entire group compared to preoperative values.

Conclusion

Our data indicate that valve sparing aortic root reimplantation is safe and effective in septuagenarians, and is associated with low early and late morbidity and mortality.

[Thoracic aortic surgery with circulatory arrest and cold cerebral perfusion]

BACKGROUND

This study was undertaken to identify pre- and perioperative risk factors to mortality and permanent neurological dysfunction (PND) and temporary neurological dysfunction (TND) in a large patient cohort, all operated under moderate hypothermic circulatory arrest (HCA) and selective antegrade cerebral perfusion (SACP) in a single centre.

PATIENT AND METHODS

Between November 1999 and March 2006, 319 patients at a median age of 65 years (range 21-86, 201 male) underwent elective aortic arch surgery with moderate HCA at 25 degrees C and additional SACP at 14 degrees C. Sixty-nine had additional coronary artery bypass grafts or valve procedures. Ninety-four (29%) had total arch repair. Statistical analysis was carried out to determine the risk factors for 30-day mortality as well as for TND and PND.

RESULTS

Overall mortality was 7.8% (15% in cases with repeat surgery vs 4.8% in nonrepeats, P=0.002). Twenty-seven (8.5%) suffered from PND, and six (22%) died during hospital stay (P=0.004). There was TND detected in 32 patients (10%). Stepwise logistic regression revealed age (P=0.001, OR 1.09/year), repeat surgery (P=0.008, OR 5.04), preoperative neurological events (P=0.004, OR 3.44), CAD (P=0.051, OR 3.58), and cardiopulmonary bypass duration (P<0.001, OR 1.01/min) as risk factors for mortality. The PND was associated with preoperative renal insufficiency (P=0.026, OR 3.34) and operation duration (P<0.001, OR 1.01/min), whereas TND occurred in patients with coronary artery disease (P=0.04, OR 2.41), and prolonged cardiopulmonary bypass duration (P=0.05, OR 1.01/min).

CONCLUSION

Thoracic aortic surgery including aortic arch using HCA and SACP can be performed with excellent results in elective patients, especially those without previous surgery. Nevertheless PND is associated with high hospital mortality. Neurological complications seem to be strongly associated with general atherosclerotic changes as well as the extent of surgery.

Valve-Sparing Aortic Root Stabilization in Acute Type a Aortic Dissection

Composite replacement is the standard approach for repair of acute type A aortic dissection involving the aortic root. Reimplantation or remodeling procedures have become valve-sparing alternatives. We developed a new and simple technique to stabilize the aortic root. A Dacron graft is attached outside the native aortic cylinder, and incised twice vertically to create openings corresponding to the right and left coronary ostia. Thus the entire graft covers the native aortic root cylinder from the outside, and the native aortic valve and coronary ostia do not need to be reimplanted. From 2002 to 2007, this technique was applied in 14 patients (8 male) with a mean age of 71 years (range, 34-83 years). Four patients died within 30 days; 3 had been hemodynamically unstable with ventilator and inotropic support preoperatively. Echocardiography showed normal function of the preserved aortic valve, without regurgitation, in all patients. This technique is an alternative valve-sparing method for stabilization of the aortic root in patients with acute type A aortic dissection.

Simulation of the fluid dynamics in artificial aortic roots: comparison of two different types of prostheses

As a consequence of the growing number of elderly people, the incidence of degenerative aortic diseases continues to increase. Often, artificial aortic roots are needed to replace the native tissue. Some physical characteristics of the artificial aortic root, however, are quite different from native aorta and need to be optimized. The supposed benefit of a prosthesis with artificial sinuses of Valsalva could first be checked by numerical calculations. Two simplified base geometries were used for simulating the flow and pressure distributions, especially in the coronary arteries. One model approximates the ascending aorta as a tube, and the other uses a design with toroidal dilation of the aortic root to approximate the native geometry of the sinuses of Valsalva. The flow and pressure distributions in both models were compared in the ascending aorta as well as in the right and the left coronary arteries. Both the pressure and the velocity distribution in the coronary artery region were not significantly higher in the model with the sinus design compared to the tube model. The sinus design only slightly increased the mean pressures and the velocities in both the ascending aorta and in the coronary arteries. Higher pressure in the coronary arteries should improve the blood circulation and decrease the risk of a surgery-related coronary incident. The sinus design did not show the hoped-for benefits, and therefore it is only a minor factor in optimizing future aortic root prostheses.

Single-stage surgical repair of type II acute aortic dissection associated with coarctation of the aorta

A 36-year-old man, who was referred for severe chest pains, was found to have acute type II aortic dissection associated with a dilated ascending aorta, aortic coarctation, and congenitally bicuspid valve. A single-stage surgical repair consisting of valve-sparing aortic root implantation and graft replacement of the ascending aorta, arch, and the coarctation segment was successful.

Current Perspective on Aortic Valve Repair and Valve-Sparing Aortic Root Replacement

Aortic valve repair and valve-sparing aortic root replacement are attractive concepts because they offer the possibility of valve competence without structural deterioration due to nonviability and they preclude the need for anticoagulation. Enthusiasm for aortic valve repair has waxed and waned over the past 45 years due in part to the inherent technical difficulties and poor mid-term results. Renewed interest in the concept of aortic valve repair has paralleled the development of valve-sparing aortic root replacement over the last 20 years. A current perspective on aortic valve repair and valve-sparing aortic root replacement is presented in the following review. Historical background, indications for repair, technical considerations, and outcomes data are discussed.