Patient-prosthesis mismatch in the context of surgical aortic valve replacement with the Trifecta bioprosthesis

Surgical aortic valve replacement (SAVR) is widely used for the treatment of aortic valve diseases. Each valve prosthesis has individual hemodynamic characteristics, which may have implications in the clinical outcome of patients. This review considers the hemodynamic performance of the St. Jude Medical Trifecta biological aortic valve prosthesis early after surgery. An essential method to determine hemodynamic parameters after SAVR is transthoracic echocardiography (TTE) that can be used to measure transvalvular flow velocities and pressure gradients. Patient-prosthesis mismatch (PPM) occurs when the orifice of the implanted prosthesis is too narrow relative to the patient’s body surface area. Postoperative PPM is thought to have a negative effect on the outcome after SAVR. The aim of this review is to summarise the current hemodynamic data of the Trifecta biological prosthesis in the aortic position. A systematic review of the literature was conducted through Pubmed, Scopus, Science Direct and Google Scholar with terms ‘‘effective orifice area”, “hemodynamic”, “gradient” combined with “Trifecta” or “Perimount”. This yielded 276 articles, 18 of which were included into a recently conducted meta-analysis. Out of those studies, ten evaluated the hemodynamics and outcome of more than 100 patients with the Trifecta prosthesis. Each of the studies showed excellent early hemodynamic results with relatively small incidence of PPM for the aortic bioprosthesis Trifecta. Moreover, the hemodynamic parameters of the Trifecta bioprosthesis seemed favourable when compared to other widely used biological valves

CORONARY PERFUSION:IMPACT OF FLOW DYNAMICS AND GEOMETRIC DESIGN OF TWO DIFFERENT AORTIC PROSTHESES OF SIMILAR SIZE

BackgroundAortic valve replacement leads to improvement of coronary flow but not to complete normalization. Coronary hypoperfusion contributes to higher left ventricular mass persistence, arrhythmias, congestive heart failure and sudden death. This prospective study compares 2 similarly sized aortic prostheses (mechanical and porcine) regarding coronary flow and hemodynamic performances in patients who underwent surgery for pure aortic stenosis.MethodsSixty patients having undergone aortic valve replacement for pure aortic stenosis with Medtronic Mosaic Ultra bioprosthesis 21 mm (n = 30) or St Jude Regent mechanical valve 19 mm (n = 30) were evaluated preoperatively and 12 months postoperatively comparing the coronary flow and the hemodynamic behavior. Echocardiography and cardiac positron emission tomography were performed at rest and during exercise or adenosine maximal stimulation, respectively.ResultsThe St Jude Regent mechanical valve, compared with the Medtronic Mosaic Ultra bioprosthesis, had reduced coronary flow reserve (2.1 ± 0.3 vs 2.3 ± 0.2; P = .003), less favorable systolic/diastolic time ratio (0.87 ± 0.02 vs 0.78 ± 0.03; P < .001), and higher mean transprosthetic gradient (46 ± 11 vs 38 ± 9; P = .003) during exercise. Multivariate analysis of impaired coronary reserve related indexed effective orifice area less than 0.65 cm/m2 (risk ratio [RR], 1.9; 95% confidence intervals [CI], 1.5-2.8; P < .001), mechanical valve (RR, 2.5; 95% CI, 1.7-3.3; P < .001), and systolic/diastolic time ratio greater than 0.75 (RR, 2.6; 95% CI, 1.8-3.8; P < .001), as well as high transprosthetic gradient (RR, 1.7; 95% CI, 1.3-2.4; P < .001) ) during exercise with coronary reserve less than 2.2.ConclusionsImprovement of coronary flow and reserve was more evident for bioprostheses than for mechanical valves. The bioprostheses demonstrated superior hemodynamics during exercise, which may have some impact on exercise capability during normal daily life

Guided Tissue Regeneration in Heart Valve Replacement: From Preclinical Research to First-in-Human Trials

Heart valve tissue-guided regeneration aims to offer a functional and viable alternative to current prosthetic replacements. Not requiring previous cell seeding and conditioning in bioreactors, such exceptional tissue engineering approach is a very fascinating translational regenerative strategy. After in vivo implantation, decellularized heart valve scaffolds drive their same repopulation by recipient’s cells for a prospective autologous-like tissue reconstruction, remodeling, and adaptation to the somatic growth of the patient. With such a viability, tissue-guided regenerated conduits can be delivered as off-the-shelf biodevices and possess all the potentialities for a long-lasting resolution of the dramatic inconvenience of heart valve diseases, both in children and in the elderly. A review on preclinical and clinical investigations of this therapeutic concept is provided with evaluation of the issues still to be well deliberated for an effective and safe in-human application

Clinical outcome and hemodynamic behavior of the Labcor Dokimos Plus aortic valve

Die Labcor Dokimos Plus Bioprothese zeigte intraoperativ keine Komplikationen und postoperativ zufriedenstellende klinische Ergebnisse mit niedriger Morbidität und Mortalität. Die hämodynamischen Eigenschaften der Prothese waren ebenfalls zufriedenstellend.The Labcor Dokimos Plus bioprosthesis showed operatively no peculiarities and a satisfactory clinical outcome with low perioperative morbidity and mortality. The hemodynamic performance of the implanted valve sizes was satisfactory

A 10-year institutional review of surgery for structural valve dysfunction in the developing world.

Masters Degree. University of KwaZulu-Natal, Durban.Background Prosthetic heart valves do not fulfil the requirements for an ideal valve, resulting in the development of prosthetic dysfunction or complications over time. Structural valve dysfunction may be influenced by multiple components which include patient’s factors, valve related factors and intraoperative factors. The inter-relation of these factors has a significant impact on morbidity and mortality associated with reoperative surgery for prosthetic valve dysfunction, particularly in a developing world where a large burden of communicable diseases together with lack of health care resources affect surgical outcome. In this study we examined the clinical records of the patients who underwent reoperative valve surgery to evaluate the clinical profile and factors that affect the surgical outcome after reoperation at a large tertiary referral center in a developing country. Objectives 1) To describe the demographic profile of patients with malfunctioning prosthetic heart valves and define their clinical presentation 2) To describe the clinical presentation of valve dysfunction 3) To determine the possible mechanisms of mechanical and bioprosthetic valve failure 4) To determine the factors affecting the immediate surgical outcomes in subjects undergoing redo cardiac prosthetic valve surgery. Materials and methods A retrospective analysis of the clinical, perioperative and follow-up data of patients who underwent redo cardiac valve surgery for structural valve dysfunction between January 2005 and December 2014 at Inkosi Albert Luthuli Central Hospital, Durban, South Africa was undertaken. Patients were identified using the Speedminer software program which is a Data Warehouse software package used to store data collected on the hospital Medicom database. The file of each of patient who underwent redo cardiac prosthetic valve replacement for structural valve dysfunction was accessed and data were extracted on age, gender, potential risk factors for valve thrombosis, symptomatology, investigations including International normalized Ratio (INR) status and follow up. All patients were evaluated preoperatively by the cardiologist and the cardiothoracic surgical team and submitted for either an elective or emergency valve replacement. Excluded from the study were those patients who underwent cardiothoracic surgery for nonvalvular reasons, i.e. coronary artery bypass surgery and congenital heart disease. Results During the ten year period (2005 to 2014) 2618 valve replacement operations were performed. During the same period 128 reoperations (4.9%) were performed in 113 patients (mean age 35.59 (SD±16.66) years). The majority of the patients were Black (72.6%) and female (75%). Fifteen patients (13.3%) were HIV infected and nine were pregnant. Acute dyspnoea (NYHA class III 34.37% and class IV 21.88%) was the presenting feature in 72 patients (56.25%). Clinical presenting features of an obstructed valve (flash pulmonary oedema with or without clinically audible prosthetic valve clicks) were documented in the clinical records of 44 of the 128 (34.4%) reoperations. In seventeen instances subjects presented with acute onset of cardiac failure (13.3%) and in eleven the presentation was characterised by signs of low cardiac output state (5.3%). There were no clinical indicators of an obstructed valve in the remaining 56 (43.8%). Of these 56 patients: 38 presented with change in effort tolerance and 18 where asymptomatic. Valve dysfunction was detected by echocardiography and confirmed fluoroscopically in 71/128 cases (55.47%). In the remaining patients the diagnosis was made either at fluoroscopy (11.72%) or on echocardiography (32.81%). The ejection fraction (EF) was severely impaired (EF<40%) in 7.08% of patients. The mean left atrial size was 52.28mm and mean pulmonary systolic pressure 45mmHg (range 26-104). Mechanical valve dysfunction was documented in 110/128 reoperations (obstructed valve (100) and prosthetic infective endocarditis (10). In almost two thirds of instances with obstructed mechanical prostheses levels of anticoagulation achieved were poor (INR4.0. HIV status did not influence the outcome of surgery and did not appear to be the main mechanism of valve obstruction. The bioprosthetic valve group comprised the remaining 18 of 128 reoperations. In this group 13/18 patients had structural valve deterioration with periprosthetic leaks, and remaining 5 had prosthetic infective endocarditis (aortic root abscess (1) and annular dehiscence (4).Emergency surgery was performed in 54.7% of the study population, of which 60.2% were in the mitral position. There was a total of 13 early in-hospital deaths (11.5%) of which one “on table” death was due to a low cardiac output state (LCOS). Postoperative mortality was related to prosthetic endocarditis (5/13) and high grade dyspnoea at presentation (7/13). Multivariate analysis revealed that bypass time >3.5 hours (HR 5.58, 95%CI 1.24-24.95), cross clamp time >120 minutes (HR 4.48, 95%CI 1.25-18.73), and third time redo operations (HR 4.26, 95%CI 1.23-14.75) were the independent predictors for early in-hospital mortality. Conclusion Our study shows a 4.9% reoperation rate after the previous valve replacement surgery with 11.5% perioperative mortality. Our results confirm that reoperative surgery is associated with significant morbidity and mortality. More than half the patients presented acutely for mechanical valve obstruction which was due to inadequate levels of anticoagulation and required emergency surgery. Early mortality was related to poor NYHA class at presentation and to the presence of infective endocarditis. An important finding of this study was the high rate of valve obstruction associated with poor anticoagulation in patients who received the Cryolife On–X valve. They had a shorter interval to valve obstruction requiring redo valve replacement compared to the other mechanical prostheses.The supervisor's name has been omitted from this research