Aortic root enlargement for aortic valve replacement in an achondroplastic dwarf

We present a case of aortic valve replacement combined with aortic root enlargement, performed on an achondroplastic dwarf with severe calcific aortic stenosis. There are no data about the incidence of valvular diseases in achondroplastic patients. To our knowledge, this is the 1st time that an aortic valve replacement associated with an aortic root enlarging procedure has been performed in this kind of patient. The aim of this report is to show that achondroplasia, in and of itself, is not a contraindication to aortic valve replacement.     

Aortic valve replacement by bioprosthesis with enlargement of the aortic ring

Small diameter aortic valve bioprostheses are associated with resting ventriculo-aortic pressure gradients of 10 to 35 mmHg. In order to avoid this factor favouring degradation of left ventricular function and early deterioration of the bioprosthesis, we enlarged the aortic ring when the diameter was less than 23 mm in patients considered unsuitable for long-term anticoagulation. The surgical technique involved incising the annulus from the postero-lateral commissure to the anterior mitral leaflet and implanting a Dacron patch lined with pericardium. Nine patients aged from 10 to 70 years (average 22 years) underwent aortic valve replacement with a Carpentier-Edwards bioprosthesis associated with enlargement of the aortic ring, between June 1979 and December 1981. The mean follow-up period is now 18 months (range 9 to 39 months). One patient has been lost to follow-up. Before surgery, 6 patients were in Stage III and 3 patients in Stage IV of the NYHA classification. There were 4 patients with pure aortic regurgitation with valve prolapse, 1 patient with aortic regurgitation due to endocarditis, and 4 patients with mixed aortic valve disease. The underlying disease was rheumatic in 6 cases, congenital in 2 cases and infective endocarditis in 1 case. The mean diameter of the aortic ring before enlargement was 19 mm. After the procedure, it increased to 23,8 mm, so enabling the implantation of no 23 and no 25 bioprostheses. Three patients had associated mitral regurgitation, 3 patients had mixed mitral valve disease, 1 patient had a membranous VSD with infundibular stenosis, and 1 patient had subvalvular aortic stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

小瓣环主动脉瓣置换并主动脉瓣环扩大术的近中期结果

目的:评价主动脉瓣环扩大成形术,在小主动脉瓣环的主动脉瓣置换术(AVR)中临床应用的近中期结果。方法:2002年1月至2007年5月,共25例小主动脉瓣环患者行AVR术,男性22例,女性3例,年龄7～64岁,平均(45±12.5)岁。术前主动脉瓣环径(18.12±1.93)mm,跨瓣压差(82±12)mmHg(1mmHg=0.133kPa)。心功能(HYHA分级):Ⅱ级20例、Ⅲ级4例及Ⅳ级1例。采用中、低温体外循环下行主动脉瓣环扩大并AVR术。Nicks法20例,Manouguian法5例。置换机械瓣18例,生物瓣5例,自体肺动脉瓣移植至主动脉瓣(Ross手术)2例。结果:死亡1例,为Ross手术后出现低心排出量综合征,出现病死率4%。其余24例住院(10±2)d。主动脉瓣环径扩大至(23.7±1.5)mm,跨瓣压差为(22±7)mmHg,与术前相比P<0.05。出院患者随访平均(24±10)个月,人工瓣和自体肺动脉瓣功能良好。心功能(HYHA分级):Ⅰ～Ⅱ级。结论:小瓣环主动脉瓣置换加瓣环扩大术近中期结果良好,远期结果有待进一步随访。     

Aortic valve replacement with autogenous aortic wall

A new operation for replacement of the severely diseased aortic valve is described. The replacement material, obtained by removing a “cylindrical” section from the ascending aorta of the same patient, is fashioned into three cusps which are sutured into proper position to form the valve. The deficiency of the ascending aorta is then replaced by a plastic sleeve graft.Also presented is the history of the first patient on whom this operation was performed. He was a 40 year old accountant with severe aortic stenosis and left ventricular failure. Following operation he improved remarkably and was able to return to work. At times, however, he suffered from episodes of fever and chest pain. During three hospital admissions, repeated unsuccessful attempts were made to identify the organism causing the irregular fever. Despite cardiac and antibiotic therapy, death occurred seven months after operation. Necropsy showed the cause of death to be a recent myocardial infarct, possibly due to an embolus from an acute ulcerating bacterial (Klebsiella pneumoniae?) endocarditis which had developed upon the autologous grafted aortic valve.A remarkable transformation in the microscopic structure of the transplanted aortic wall then functioning as cusp tissue was observed. Speculation as to its possible significance raises exciting considerations. Is it degenerative or is it a metaplastic attempt to adjust to new functional requirements?The postoperative course in this case provides diagnostic and therapeutic clues that may prove valuable in preventing such an untoward outcome in future cases.     

Results of replacement of cardiac valves by homologous dura mater valves.

Homologous dura mater valve was employed in a series of 533 patients in the period between January 1971 and May 1974. The dura mater was sterilized and preserved in 98 percent glycerol solution at room temperature. Important data were the following (1) no significant pressure gradient through the vale at rest; (2) no bacterial endocarditis; (3) two cases of fungal endocarditis; (4) no degeneration or retraction of the leaflets; (5) no thrombus formation in the valve; and (6) no anticoagulants were used in this series.     

Aortic valve replacement with sutureless and rapid deployment aortic valve prostheses

Aortic valve stenosis is the most common valve disease in the western world. Over the past few years the number of aortic valve re-placement (AVR) interventions has increased with outcomes that have been improved despite increasing age of patients and increasing burden of comorbidities. However, despite such excellent results and its well-established position, conventional AVR has undergone great development over the previous two decades. Such progress, by way of less invasive incisions and use of new technologies, including transcatheter aortic valve implantation and sutureless valve prostheses, is intended to reduce the traumatic impact of the surgical procedure, thus fulfilling lower risk patients’ expectations on the one hand, and extending the operability toward increasingly high-risk patients on the other. Sutureless and rapid deployment aortic valves are biological, pericardial prostheses that anchor within the aortic annulus with no more than three sutures. The sutureless prostheses, by avoiding the passage and the tying of the sutures, significantly reduce operative times and may improve outcomes. However, there is still a paucity of robust, evidence-based data on the role and performance of sutureless AVR. Therefore, strongest long-term data, randomized studies and registry data are required to adequately assess the durability and long-term outcomes of sutureless aortic valve replacement.     

Successful management of dissection of the aortic root during aortic valve replacement

We present a case of intraoperative dissection of the aortic root in a patient with non-calcified aortic valve incompetence. This complication led to life-threatening bleeding from the dissection line into the layers of the left ventricle as well as the aortic wall with formation of an increasing subadventitial hematoma. The only possible management was to remove the valve prosthesis and to close the entry site of the dissection when reinserting the valve implant. The mechanism of this complication is discussed.     

同种异体带瓣主动脉行主动脉根部置换的临床效果

目的 :探讨应用低温保存的同种异体带瓣主动脉行主动脉根部重建手术的临床效果。方法 :85例主动脉瓣膜病变患者行同种主动脉根部置换手术 ,术后随访观察临床结果。结果 :随访 39± 13（1.5～ 91）个月。早期手术死亡率 1% （1/ 85 ） ,远期手术死亡率 6 % （5 / 85 ） ;与术前比较心功能明显改善 （P<0 .0 5 ） ;术后随访心内膜炎发生率占2 % （2 / 85 ） ;生存者中瓣膜无或有轻度返流 84 % （6 6 / 79） ,中度返流 16 % （13/ 79）。结论 :同种异体带瓣主动脉根部重建手术效果可靠 ,且并发症少。     

Allograft aortic root replacement for aortic valve endocarditis with aortopulmonary fistula

Acute infective endocarditis affecting the aortic root and valve associated with development of a fistulous communication between the aorta and pulmonary artery was presented in a young Turkish girl. Emergency surgery was required. Operation consisted initially of closure of the defect on the main pulmonary artery with a pericardial patch. This was followed by allograft aortic root replacement.     

Aortic valve leaflet disruption techniques in transcatheter aortic valve replacement

With continued technological advancement and technical improvement of transcatheter aortic valve replacement (TAVR), it has become a desirable treatment option for aortic valve stenosis. Its minimally invasive approach compared to surgical aortic valve replacement offers the treatment to a broader patient population, mainly non-surgical candidates. A feared complication of TAVR is the occlusion of coronary artery ostium by the native aortic valve leaflet due to its displacement by the expanded transcatheter valve. Bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction (BASILICA) is a technique developed to mitigate this risk by creating a lengthwise laceration of the left and/or right aortic valve leaflets prior to TAVR. Patient outcomes following TAVR with BASILICA have been promising. Meticulous preoperative examination, patient selection, and hemodynamic management are imperative. With continued refinement, BASILICA may further expand the application of TAVR to patients at high risk for coronary occlusion associated with the procedure.

Since the very first human transcatheter aortic valve replacement (TAVR) procedure in 2002, more than 200,000 TAVRs have been performed worldwide.^[1] Though it was reserved for select non-surgical candidates in the early stages of development, its application is expanding considerably in recent years. Large randomized controlled studies have compared outcomes of TAVR versus surgical aortic valve replacement (SAVR) for intermediate and high-risk patients and found no significant difference in primary outcome of morbidity from major stroke or mortality at one year and two years, respectively.^[2,3] Furthermore, a study of similar design involving low-risk patients found that TAVR patients had significantly lower rate of death, stroke, or rehospitalization at one year.^[4] Another evolving application of TAVR is to salvage a failing bioprosthetic valve, known as valve-in-valve (ViV) procedure.^[5] Minimally invasive aspect of TAVR confers a major advantage over SAVR, and the patient outcomes have been promising thus far. Despite its advantages, TAVR is associated with several notable risks. Firstly, without follow-up data from past six years, the durability of TAVR valves is uncertain. Therefore, current recommendations still favor SAVR for younger patients with longer life expectancy.^[6,7] However, one of the most consequential intraoperative complications of TAVR is the occlusion of coronary artery. With the placement of the prosthetic valve, an existing aortic valve leaflet may displace outward and directly occlude the adjacent coronary ostium or block the entire sinus of Valsalva, resulting clinically significant coronary obstruction. The left coronary ostium is much more frequently affected than the right coronary ostium, likely due to its lower height of the ostium in relation to the leaflet.^[8] Most cases of coronary obstruction manifest as severe hypotension immediately following the deployment of the prosthetic valve.^[8–10] The incidence is less than 1% in TAVR performed on native aortic valves, but it increases over 3-fold in ViV TAVR procedures.^[11,12] Majority of patients with TAVR-related coronary obstruction in the past have received emergent percutaneous coronary intervention and a much smaller number received coronary artery bypass grafting.^[8] Despite these measures, the 30-day mortality of coronary obstruction in patients undergoing ViV TAVR is reported to be 48.6%, which is likely much higher than in patients with coronary obstruction during native valve TAVR.^[8,11]Given the high rate of catastrophic outcomes associated with coronary obstruction, efforts must be devoted to preventive strategies. Several factors have been identified which include pre-existing surgical bioprosthetic aortic valve, older age, female gender, no history of coronary artery bypass grafting, and higher risk profile according to the logistic European System for Cardiac Operative Risk Evaluation (logEuroSCORE).^[10] The patient characteristics are likely significant due to the anatomic variability associated with them which include significantly smaller aortic annulus areas, sinus of Valsalva diameters, sino-tubular junction diameters, and lower left coronary artery heights as.^[10] In ViV patients, the prior surgical valve location, manipulation of the aortic root, and implantation of coronary grafts may affect these parameters considerably.^[12] With knowledge of these factors contributing to the risk of coronary obstruction, meticulous protocols are applied to stratify patient risk, as well as to plan the procedure appropriately.^[13,14]Bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction (BASILICA) is a novel technique developed to create a lengthwise laceration down the middle of an aortic valve leaflet from the base to the tip.^[15] The goal of this technique is to prevent coronary obstruction by creating a separation in the existing valve leaflet through which the coronary artery can remain open and perfused when the leaflet is displaced outward by the transcatheter valve and the details have been previously described.^[14,15] Briefly, this is accomplished by traversing an electrified guidewire through the mid-base of the valve leaflet of interest. The guidewire is then captured by a ring snare pre-positioned at the aortic outflow tract through a separate catheter. Then the guidewire and snare are both manipulated to position the cutting segment of the electrified guidewire in contact with the valve leaflet, which creates the valve laceration with electrocautery (Figure 1).Open in a separate windowFigure 1Schematic illustration (A) and transesophageal echocardiography (B) of mid-esophageal long axis view showing the electrocautery apparatus (arrow) in place for BASILICA.BASILICA: bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction.Initial testing of BASILICA in swine revealed successful laceration of the aortic valve leaflet without collateral injury on necropsy, except in the first trial while refining the technique.^[15] Clinical trial was subsequently performed and showed promising results.^[16] Of 30 patients, all subjects were free of coronary obstruction, despite being categorized as high risk based on preoperative evaluation.^[16] Due to the relatively small sample size, several questions remained unanswered regarding the safety of BASILICA, such as the risk of stroke and major vascular complications. However, many centers began to perform BASICILA over the recent years, including here at UC Davis Medical Center. As a result, the multicenter international BASILICA registry has accumulated data on 214 patients who underwent the procedure at 25 centers in North America and Europe.^[17] Analysis of the registry revealed that leaflet laceration was performed successfully in 94.4% of the patients and among those patients, 4.7% of patients experienced partial or complete coronary occlusion.^[17] The patients with coronary obstruction were successfully treated with coronary stents, but one patient died from cardiogenic shock despite the interventions. Considering the previously established mortality ranging between 40% and 50% in patients who experience coronary obstruction due to TAVR without BASILICA, the mortality of 10% in patients who experience coronary obstruction with BASILICA bolsters the benefits of this procedure.^[18] The authors’ explanation for this finding is that the obstruction resulting after BASILICA is not flow-limiting and the space created by BASILICA often allows placement of coronary stents through the struts of the transcatheter valve, instead of the traditional “snorkel” stent.^[17] Overall, the 30-day mortality and incidence of stroke reported through this registry were 2.8% and 2.8%, respectively.^[18] This is similar to the data of all patients undergoing TAVR reported by the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry.^[18] Considering that patients who underwent BASILICA are at higher risk than the average TAVR patients, this result supports the implementation of BASILICA for this subset of patients.BASILICA requires meticulous planning and certain patient factors make the procedure less feasible. A large portion of the failed BASILICA were attributed to failure to traverse the electrified guidewire through the leaflet due to the extensive calcification. Hence, it may be a relative contraindication for the procedure. Anesthetic planning is also an important component in taking care of these hemodynamically fragile TAVR patients. This is highlighted by the authors of the BASILICA registry analysis, who attributed one of the deaths to cardiogenic shock resulting from the anesthesia induction.^[18] Although moderate sedation may be considered, there is a strong preference for general anesthesia (GA) with endotracheal intubation. In case of severe hemodynamic compromise that requires emergent surgical intervention or mechanical circulatory support, GA with a secure airway is necessary. Furthermore, transesophageal echocardiogram (TEE) can be performed much more safely with a secured airway with an endotracheal tube. Particularly in this patient population, critical intraoperative complications, such as wall motion abnormalities can be detected early using TEE to direct clinical management.

Aortic valve repair versus replacement in bicuspid aortic valve disease

BACKGROUND AND AIM OF THE STUDY: The study aim was to compare the results of aortic valve repair and replacement with biological valves in adult patients with aortic insufficiency (AI) caused by congenital bicuspid aortic valve (BAV) METHODS: Forty-four patients who had aortic valve repair were matched for age and left ventricular function to 44 patients who had aortic valve replacement (AVR) with biological valves. Patients were followed annually using echocardiography. The mean follow up was 2.6 +/- 2.1 years for the repair group, and 3.5 +/- 2.1 years for the replacement group. Follow up was complete. RESULTS: There was no operative or late death in either group. Early postoperative echocardiography showed trace or no AI in 35 patients and mild AI in nine who had repair, and trace or no AI in 38 patients and mild AI in five who had AVR. The mean peak systolic gradient was 16.2 +/- 7.6 mmHg for repair and 13.2 +/- 7.2 mmHg for AVR. Four patients who had valve repair and two who had AVR, needed repeat aortic valve surgery because of progressive AI or endocarditis. Freedom from reoperation at five years was 91 +/- 5% for repair and 94 +/- 6% for replacement (p = 0.2), while freedom from moderate or severe AI at five years was 79 +/- 8% for repair and 94 +/- 6% for replacement (p = 0.024). The peak systolic gradient at follow up was 11.7 +/- 6.8 mmHg after repair and 13.3 +/- 9.6 mmHg after AVR (p = 0.4). There were no thromboembolic complications in either group. CONCLUSION: Repair of BAV is feasible in certain patients with AI, but the hemodynamics and clinical outcomes do not appear to be superior to AVR with biological valves during the first five years of follow up.     

Aortic valve replacement for aortic stenosis in nonagenarians

We reviewed certain clinical and morphologic findings in 9 patients who had aortic valve replacement (AVR) for aortic stenosis (AS) when >or=90 years of age. All had AVR from February 2000 to April 2006. The aortic valve areas ranged from 0.41 to 1.00 cm2, and the transvalvular peak systolic gradients ranged from 20 to 110 mm Hg. The left ventricular ejection fractions were >or=50% in 6 of the 9 patients. The aortic valve was congenitally bicuspid in 3 patients, and the operatively excised valves in them weighed 4.20, 5.73, and 9.75 g, respectively (mean 6.56). The other 6 patients had 3-cuspid valves without commissural fusion, and the operatively excised valves in them weighed 0.43, 0.94, 1.08, 1.51, 1.98, and 4.43 g, respectively (median 1.30, mean 1.73). Coronary artery bypass grafting (CABG) was performed at the time of AVR in 8 of the patients. One patient died a day postoperatively and 2 others died 874 and 1,011 days, respectively, after operation. Two were in skilled nursing units postoperatively for several weeks. In conclusion, AS can be severe in nonagenarians and may be superimposed on a congenitally bicuspid aortic valve.     

Aortic valve sparing in 120 patients with aortic root aneurysms

Introduction and objectives

Several aortic valve sparing techniques have been described for the treatment of aortic root aneurysms. We report our experience using the reimplantation technique in 120 patients.

Methods

Between March 2004 and October 2010, 120 patients with aortic root aneurysms underwent David operations. Of these, 51 were diagnosed with Marfan syndrome. Mean patient age was 31 ± 12 years. The mean diameter of the sinuses of Valsalva was 51 ± 5 mm and moderate/severe aortic regurgitation was present in 16% of these patients. In the other 69 patients mean age was 56 ± 14 years, the mean diameter of the sinuses of Valsalva was 53 ± 7 mm and moderate/severe aortic regurgitation was present in 66%. A bicuspid aortic valve was presented in 14 cases.

Results

Hospital mortality was 1.7%. Mean follow-up was 37 ± 21 months; 94% of the patients survived and 96% had an aortic regurgitation below grade II during 5 years of follow-up. One patient required re-operation because of severe aortic regurgitation. No endocarditis or thromboembolic complications have been documented, and 96% of the patients did not receive any anticoagulation therapy.

Conclusions

Short- and mid-term results with the reimplantation technique for aortic root aneurysms are excellent. This technique prevents the need for chronic anticoagulation treatment as well as the complications arising from mechanical prostheses, and it should be the treatment of choice for young patients.Full English text available from: www.revespcardiol.org     

Valve-sparing root replacement after prior Starr-Edwards aortic valve replacement

Historically, patients with prior aortic valve replacements who subsequently present with an ascending aortic aneurysm require placement of a valve conduit. However, if the patient has a functional mechanical valve with proven long-term durability, an attempt can be made to preserve the intact valve and to graft the aneurysmal aortic root. The case is described of a patient with a previously placed Starr-Edwards aortic valve who subsequently developed a 6-cm ascending aortic aneurysm. By removing the valve ball and using the existing sewing ring, a proximal graft anastomosis was created with ease, eliminating valve excision.