Mechanical Aortic Valve Replacement Research Articles

Massive aortic regurgitation in the background of a quadricuspid aortic valve

A 52-year-old woman, with a previous history of hypertension, was admitted to our institution presenting exertional dyspnea. A comprehensive study was performed including a cardiology examination and echocardiography. Transesophageal echocardiography detected a quadricuspid aortic valve with a central severe aortic valve insufficiency. Moreover, a discrete dilation of the aortic root was seen. Left ventricular ejection fraction was in normal range. A computed tomography scan was performed especially to recognize any displacement of the coronary ostia and evaluate the aortic valve (Fig. A). No abnormality of coronary artery origin was confirmed. Surgical treatment was proposed, and the patient underwent open-heart surgery. Quadricuspid valve was confirmed (Fig. B). An aortoplasty to reduce the ascending aorta and a mechanical aortic valve replacement were performed. The postoperative course was favorable, and the patient had an uneventful recovery. Postoperative echocardiography assessment confirmed normal prosthetic aortic valve function and left ventricular ejection fraction. Quadricuspid aortic valve is a rare congenital abnormality, with an estimated incidence of 0.04%. In approximately 80-90% of cases, it is related to an aortic valve dysfunction. Quadricuspid aortic valve is usually associated with additional malformations, mainly related to the origin of coronary arteries. Due to the presence of an additional leaflet, absence or displacement of coronary ostia has been found in 10% of cases. It is of utmost importance to prevent coronary ostia obstruction with valve prosthesis implantation, and to plan myocardial protection during cardiopulmonary bypass. In the presence of prior surgery for congenital aortic valve abnormalities and regardless of patient age, we highlight the necessity to perform a careful evaluation of the coronary anatomy. 780

131: Long-term outcomes following isolated mechanical aortic valve repalcement in young adults

The ideal aortic valve substitute for young adults (<65 years) undergoing isolated aortic valve replacement (AVR) remains unknown. This is partly due to the lack of data on long-term outcomes in this specific patient population. The aim of this study was to determine long-term outcomes (survival and valve-related complications) in a contemporary series of consecutive young adults undergoing isolated mechanical AVR. Between 1997 and 2006, 1159 patients underwent AVR at our institution. All patients undergoing concomittant or redo procedures were excluded. Of those, 470 patients <65 years of age undergoing isolated mechanical AVR were identified. Mean age of the patients was 53.2±9.2 years (303 male and 167 female). Long term follow-up data were prospectively collected through a dedicated valve clinic. Additional information was obtained retrospectively from medical records. Lifetable analyses were used to determine age- and gender-matched general population survival in the province. Mean follow up was 4.7±4.7 years. Overall actuarial survival at 1, 5 and 10 years was respectively 98±2%, 93±2% and 80±3%, which is lower than the age- and gender-matched general population in the province (Figure). Actuarial freedom from prosthetic valve dysfunction was 99±1%, 92±2% and 88±8% at 1, 5 and 10 years respectively. Actuarial freedom from valve reintervention was 98±1%, 93±1% and 89±2% at 1, 5 and 10 years respectively. Actuarial freedom from thrombo-embolism was 96±1%, 90±2% and 87±2% at 1, 5 and 10 years respectively. In young adults undergoing isolated mechanical AVR, survival is lower than expected in an age- and gender-matched general population. Furthermore, there is a low but constant hazard of prosthetic valve reintervention following mechanical AVR. Further studies are required to determine the ideal valve substitute in young adults undergoing AVR.

Diagnosis of tertiary treponema pallidum infection using pola polymerase chain reaction (PCR)

<h3>Background</h3> Syphilis is primarily diagnosed serologically. Poly-merase chain reaction (PCR) is increasingly used as an adjunct in diagnosis. We describe the first case of using polA syphilis-specific PCR to make the diagnosis of syphilis aortitis. <h3>Case</h3> A 36-year-old Indian male had a 2 day history of fever and back pain. Examination revealed severe aortic regurgitation. Transoesophageal echocardiography demonstrated coronary cusp destruction with severe aortic regurgitation. Multiple blood cultures and investigations for ‘culture-negative endocarditis' were unhelpful. Computed tomography of the thorax revealed normal thickness aorta. An empiric endocarditis antibiotics regimen was initiated and the patient had a mechanical St Jude's aortic valve replacement. Histology of aortic intima and aortic valve revealed acute on chronic inflammation and prominent plasma cells. 16S rRNA PCR didn't yield a bacterial sequence. Syphilis serology revealed positive Syphilis TP (Architect), <i>Treponema pallidum</i> particle agglutination (TPPA), total antibody enzyme immunoassay (EIA) and IgM EIA; whilst rapid plasma reagin (RPR) reactive, titre 1:64. <i>Treponemal pallidum</i> polA PCR was retrospectively performed on aortic intima and returned positive. The patient had his empiric antibiotics ceased and completed 15 days of IV penicillin. <h3>Conclusion</h3> The correct use of organism-specific targets in PCR can be considered to aid diagnosis. This is a proof of concept testing that may help certain cases of syphilis diagnosis in the future.

Type A aortic dissection presenting as superior vena cava syndrome

A 51-year-old man presented with a 5-day history of progressive facial swelling, sensation of head fullness, increasing shortness of breath and paroxysmal nocturnal dyspnea. He denied chest pain, syncope or presyncope. Past medical history included mechanical aortic valve replacement 7 years prior and atrial fibrillation treated with warfarin. A clinical diagnosis of acute superior vena cava (SVC) syndrome was made. Portable chest radiograph showed a widened superior mediastinum. Computed tomography scan of the thorax demonstrated a large type A aortic dissection almost completely effacing the SVC. Acute type A aortic dissection (AD) is an emergency requiring prompt diagnosis and treatment. Patients typically present with acute onset of chest and/or back pain, classically described as "ripping" or "tearing." SVC syndrome is rarely, if ever, mentioned as a presentation, as it is usually due to more chronic conditions. This case illustrates a rare incidence of type A AD actually presenting as SVC syndrome.

Transatrial Antegrade Approach for Double Mitral and Tricuspid “Valve-in-Ring” Implantation

Within the last 5 years, the number of transcatheter aortic valve implantation (TAVI) procedures has increased continuously and, in parallel, the indications for TAVI have expanded (eg, failing surgical valves and rings). Furthermore, alternative TAVI access routes such as transaxillary and transaortic have been applied successfully. We report on, to our knowledge, the first-in-human case of a combined off-pump antegrade transatrial implantation of a transcatheter valve within a mitral and tricuspid annuloplasty ring through an anterolateral minithoracotomy. The patient showed severe mitral valve and tricuspid valve stenosis and regurgitation 15 years after mitral valve repair and 7 years after aortic valve replacement and tricuspid valve repair.

Thromboelastography to monitor the intra‐operative effects of low‐molecular weight heparin following bridging anticoagulation in a child with normal renal function*

Paediatric patients who require anticoagulation with therapeutic doses of low-molecular weight heparin are at risk of having a residual anticoagulant effect at the time of surgery, even if managed according to current peri-operative guidelines. Testing for residual effect is not currently recommended in such circumstances. A 15-year-old child with a mechanical aortic valve replacement requiring long-term warfarin treatment, as well as underlying coagulation defects, was administered low-molecular weight heparin for bridging anticoagulation before kyphoscoliosis surgery. Thromboelastography was used intra-operatively to diagnose residual heparinisation, which was demonstrated by a prolonged reaction (R) time of 16.0 min in the plain cup, compared with 9.2 min in the heparinase cup. Subsequently, thromboelastography was also used to monitor haemostatic therapy, which consisted of protamine 2 mg.kg(-1) and 500 IU cryoprecipitate. Thromboelastography was used intra-operatively to allow rapid testing of coagulation status and guide therapy, thereby minimising use of blood products and reducing complications.

141 Long-Term Outcomes Following Isolated Mechanical Aortic Valve Replacement In Young Adults

141 Long-Term Outcomes Following Isolated Mechanical Aortic Valve Replacement In Young Adults

Successful catheter ablation of ventricular tachycardia at a site with manifest entrainment and a long postpacing interval: What is the mechanism?

A 66-year-old man, with a long history of rheumatic heart disease, valvular cardiomyopathy, and congestive heart failure, underwent a mechanical mitral and aortic valve replacement in 1995. In 2005, an implantable cardioverter defibrillator (ICD) was implanted because of nonsustained ventricular tachycardia (VT) and a reduced left ventricular function (left ventricular ejection fraction, 30%). In 2010, the patient developed a VT storm refractory to amiodarone, sotalol, lidocaine and beta-blockers, and received multiple ICD shocks. There were at least 3 clinical VTs. VT1 exhibited a right bundle-branch block (RBBB) morphology, northwest axis, and a cycle length (CL) of 560 ms; VT2 exhibited an RBBB morphology, right-axis deviation, and CL of 490 ms; and VT3 had a left bundle-branch block (LBBB) morphology, right-axis deviation, and CL of 430 ms. During the electrophysiological study, the VTs were induced by programmed ventricular stimulation, hence bundle branch reentry was ruled out. Mapping in the coronary veins during VT suggested an epicardial circuit of the tachycardia. Electroanatomical mapping in the epicardium using a NaviStar catheter (Biosense-Webster, Diamond Bar, California) revealed the presence of a wide low-voltage area in the apical region. During the induced VT1 a presystolic potential (PP) was recorded from this area, which preceded the onset of the QRS by 60 ms (Fig. 1A). Entrainment pacing with a 9.9 V output (1.0 ms width) was performed from this site at a CL of 500 ms. The surface ECG during entrainment pacing showed some degree of fusion. The interval between the pacing stimulus and onset of the QRS complex (S-QRS) was 160 ms, whilst the interval from the electrogram recorded at the pacing site to the QRS onset during the VT (Eg-QRS) was just 60 ms. The post-pacing interval (PPI) was 680 ms (120 ms longer than the VT–CL). A radiofrequency (RF) energy application using open irrigation (30 ml/min, 35 W)

080 Safety of LMWH for bridging anticoagulation before full warfarinisation in mechanical valves

ObjectiveEarly following mechanical heart valve replacement, patients are at high risk of valve thrombosis and bleeding complications. There are no published guidelines on the use of specific bridging therapies until...

Staphylococcus Aureus Endocarditis Complicated by Aortic Root Abscess, Coronary Fistula, and Mitral Valve Perforation

![Figure][1] [![Graphic][3] ][3][![Graphic][4] ][4][![Graphic][5] ][5][![Graphic][6] ][6] A 62-year-old man with recurrent Staphylococcus aureus endocarditis in the setting of previous mechanical aortic valve replacement, coronary artery bypass graft, and multiple

Redo Autograft Operations After the Ross Procedure

Autograft dilatation after the Ross procedure is the most common cause of late autograft failure. We looked at results after reoperation for autograft dysfunction using autograft sparing and composite root replacement techniques. Data were abstracted from our prospectively collected Ross registry for 160 consecutive patients who underwent a Ross procedure by a single surgeon between 1994 and 2008. Follow-up records were obtained, and the last echocardiographic report after reoperation was analyzed. Autograft reoperation was necessary in 17 patients, at a median interval of 6.9 years after the original procedure. Indications for reoperation were insufficiency with autograft dilatation in 16 patients, and without dilatation in 1 patient. Surgical procedures used at reoperation included autograft reimplantation in 6 patients (35.3%), autograft remodeling procedure in 1 patient (5.9%), composite root replacement with mechanical valved conduit in 5 patients (29.4%), composite root replacement with biologic valved conduit in 3 patients (17.6%), and mechanical aortic valve replacement in 2 patients (11.8%). At a median follow-up of 5.0 years after reoperation, freedom from greater than 2+ aortic insufficiency was 100% (17 of 17 patients) in both reimplantation and replacement groups. There was 1 death after reoperation (at >14 years) related to complications from systemic lupus erythematosus. There have been no strokes after autograft reimplantation. Autograft valve reimplantation and composite aortic root replacement are effective treatments for aortic root dilatation and aortic insufficiency after the Ross procedure. Echocardiographic follow-up demonstrates reasonable short-term function after autograft preservation procedures.

What do you do with the antiplatelet agents in patients with drug eluting stents who then receive a mechanical valve?

Dual antiplatelet therapy (DAT) with aspirin and clopidogrel is a cornerstone of treatment during and after percutaneous coronary interventions with drug-eluting stent (DES) implantation. Oral anticoagulation (OAC) is the recommended treatment for patients with mechanical heart valves. When patients with DES need a mechanical heart valve or vice versa, we face the difficult choice of their antithrombotic therapy. Different institutions empirically follow a combination of OAC and single or DAT, the so-called triple antithrombotic therapy (TT) aiming to find the best balance between the thrombotic and bleeding risk for this subset of patients. A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether there is an optimal antithrombotic management for patients with DES undergoing mechanical heart valve or vice versa. Altogether, more than 148 papers were found using the reported search, of which 16 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that DES implantation in patients who could potentially need valve surgery in the future should be discouraged and bare-metal stent or an aortic bioprosthesis preferred. However, in high-risk patients with DES, the recommendation is to postpone elective surgery for 1 year and, if surgery cannot be deferred, continue aspirin during the perioperative period. Moreover, when OAC is given in combination with clopidogrel and/or low-dose aspirin, the target INR should be 2.0-2.5 (Class IIb, level of evidence C). As per the long-term management, antithrombotic management with DAT alone in mechanical aortic valve replacement might be possible, but there is not enough evidence to support it. The available evidence suggests that triple anticoagulation (OAC+DAT) is associated with the best clinical outcome compared with all the other possible strategies. The duration of TT should be 3 months after sirolimus DES implantation, and 6 months after paclitaxel DES implantation, followed by long-term therapy with OAC plus clopidogrel or aspirin with either PPIs, or H2-receptor antagonists (Class IIa Level of Evidence C).

Mechanical Aortic Valve Replacement in Young Women Planning on Pregnancy: Maternal and Fetal Outcomes Under Low Oral Anticoagulation, a Pilot Observational Study on a Comprehensive Pre-Operative Counseling Protocol

This pilot prospective observational study aimed to evaluate the maternal and fetal outcomes of pregnancies under low-dose oral anticoagulation therapy after aortic mechanical replacement. Need for valve replacement is still an issue for young women with native valve disease who are planning on future pregnancy. Choice of replacement device is a challenging clinical task. A comprehensive pre-operative counseling protocol to guide choice of replacement device was developed. The pre-operative anticoagulation trial to determine the warfarin daily dosage needed to reach target international normalized ratio (INR) represented the main stem of such protocol. Pregnancies on low-dose anticoagulation therapy (target INR: 1.5 to 2.5) were allowed in a highly selected subset of mechanical aortic valve recipients. Twenty-two patients of 40 originally referred for native valve disease surgery requiring valve replacement, safely underwent the pre-operative anticoagulation challenge. No maternal or fetal complications were detected in 16 pregnancies under low oral anticoagulation. Patterns of warfarin daily dosage and induced INRs were characterized during pregnancy. In this small sample observational study, a pre-operative anticoagulation therapy trial helped young women scheduled for valve replacement to acquire complete information as to the choice of prosthetic device. In selected third-generation mechanical aortic prosthesis recipients, low-dose anticoagulation therapy seems safe and feasible for both mother and fetus. Further studies are needed to validate this approach.

Ten-year comparison of pericardial tissue valves versus mechanical prostheses for aortic valve replacement in patients younger than 60 years of age

Aortic valve replacement using a tissue valve is controversial for patients younger than 60 years old. The long-term survival in this age group, the expected event rates during long-term follow-up, and valve-related complications are not clearly determined. From January 2000 to December 2009, overall survival, valve-related events, and echocardiographic outcomes were analyzed in all patients younger than 60 years of age, who underwent biologic aortic valve replacement. Patients who received a Perimount Carpentier-Edwards pericardial tissue valve (n = 103) were selected and compared with a propensity matched group of 103 patients who received aortic valve replacement using a mechanical bileaflet valve. The mean follow-up was 33 ± 24 months (range, 2-120), and the mean age at implantation was 50.6 ± 8.8 years (bioprosthesis, 55 ± 8.9 years; mechanical valve, 50 ± 8.6 years; P = .03). Survival was significantly reduced in patients after biologic aortic valve replacement (90.3% vs 98%; P = .038). Freedom from all valve-related complications (bioprosthesis, 54.5%; mechanical valve, 51.6%; P = NS) and freedom from reoperation (bioprostheses, 100%; mechanical valve, 98%; P = NS) were comparable in both groups. The average transvalvular mean (11.2 ± 4.2 mm Hg vs 10.5 ± 6.0 mm Hg, P = .05) and peak (19.9 ± 6.7 mm Hg vs 16.7 ± 8.0 mm Hg, P = .03) gradients were greater after biologic aortic valve replacement. Regression of the left ventricular mass index was more pronounced after mechanical valve replacement (118.5 ± 24.9 g/m(2) vs 126.5 ± 38.5 g/m(2); P = NS). The echocardiographic patient-prosthesis mismatch was greater at follow-up after biological aortic valve replacement (0.876 ± 0.2 cm(2)/m(2) vs 1.11 ± 0.4 cm(2)/m(2); P = .01). Oral anticoagulation was a protective factor for survival among the bioprosthetic valve patients (P = .024). In the present limited cohort of patients younger than 60 years old, biologic aortic valve replacement was associated with reduced mid-term survival compared with survival after mechanical aortic valve replacement. Despite similar valve-related event rates in both groups, the better hemodynamic performance of the mechanical valves and/or protective effect of oral anticoagulation seemed to improve the outcome. The transcatheter valve-in-valve intervention as potential treatment of tissue valve degeneration should not be considered the sole bailout strategy for younger patients because no evidence is available that this would improve the outcome.

Ross Procedure versus mechanical aortic valve replacement at 10 years? A prospective randomized trial

Objectives: The objective of this study was to compare long term performance of pulmonary autografts with mechanical aortic valves, in the treatment of aortic valve stenosis.

Aortic Prosthetic Valve Endocarditis Caused by an Unusual Microorganism, Gemella sanguinis

IntroductionWe report the first case of prosthetic valve endocarditis caused by Gemella sanguinis.CaseA 27-year-old woman with a history of rheumatic heart disease with mechanical aortic and mitral valve replacements reported a recent toothache treated with amoxicillin, with improvement. Several day

Aortic valve replacement surgery for a case of infantile Takayasu arteritis

Takayasu arteritis is a chronic inflammatory disease of unknown etiology primarily affecting the aorta and its major branches and usually occurring in the second or third decade of life. Here, we report a case of Takayasu arteritis in a 10-month-old patient. The infant presented with signs of congestive heart failure and severe aortic regurgitation. Echocardiography and computed tomography angiography showed an abnormally dilated thoracic and abdominal aorta. The infant was initially treated with prednisolone, followed by commissuroplasty of the aortic valve but neither approach ameliorated the heart failure. The patient was eventually treated with a mechanical aortic valve replacement surgery at the age of 12 months, and her condition stabilized. Although unusual, this case indicates that the diagnosis of Takayasu arteritis should be considered in children with unexplained systemic symptoms, aortic valve regurgitation, and heart failure. Because severe aortic regurgitation may be a fatal complication of Takayasu arteritis, early aortic valve replacement surgery should be considered, even in very young children.

Six uneventful years with a pacing lead in the left ventricle

A 61-year-old asymptomatic man was referred to our institution for surgical repair of an aortic root aneurysm. His medical history was significant for mechanical aortic valve replacement 9 years ago, subsequent long-term anticoagulation, and dual-chamber pacemaker implantation for heart block 6 years ago. A preoperative electrocardiogram (Figure 1A) showed a right bundle branch block pattern of paced beats that raised the suspicion of lead malposition in the left ventricle (LV). Lateral (Figure 1B) and posteroanterior (Figure 1C) chest radiography further suggested the diagnosis. On the lateral chest radiography, the ventricular lead (arrow) appeared to

Ventricular Pacing via the Coronary Sinus in a Patient with a Mechanical Tricuspid Valve Prosthesis

Implantation of a transvenous endocardial pacing lead in the right ventricle is contra‐indicated after mechanical tricuspid valve replacement; therefore a surgical approach to the epicardium is usually required. This case report describes ventricular pacing via a branch of the coronary sinus in a patient with mechanical mitral, aortic and tricuspid valve replacements. In conclusion, this approach is minimally invasive, provides effective ventricular stimulation with low pacing threshold and stable lead position, and is a feasible option when transvenous right ventricular pacing is not possible.

Prospective Randomised Study to Determine the Clinical Outcomes After Tissue and Mechanical Aortic Valve Replacement in Patients Aged 55–70 Years

Prospective Randomised Study to Determine the Clinical Outcomes After Tissue and Mechanical Aortic Valve Replacement in Patients Aged 55–70 Years