Prosthesis Dysfunction Research Articles

Artificial aortic valve dysfunction due to pannus and thrombus - different methods of cardiac surgical management.

IntroductionApproximately 60 000 prosthetic valves are implanted annually in the USA. The risk of prosthesis dysfunction ranges from 0.1% to 4% per year. Prosthesis valve dysfunction is usually caused by a thrombus obstructing the prosthetic discs. However, 10% of prosthetic valves are dysfunctional due to pannus formation, and 12% of prostheses are damaged by both fibrinous and thrombotic components. The authors present two patients with dysfunctional aortic prostheses who were referred for cardiac surgery. Different surgical solutions were used in the treatment of each case.Case study 1The first patient was a 71-year-old woman whose medical history included arterial hypertension, stable coronary artery disease, diabetes mellitus, chronic obstructive pulmonary disease (COPD), and hypercholesterolemia; she had previously undergone left-sided mastectomy and radiotherapy. The patient was admitted to the Cardiac Surgery Department due to aortic prosthesis dysfunction. Transthoracic echocardiography revealed complete obstruction of one disc and a severe reduction in the mobility of the second. The mean transvalvular gradient was very high. During the operation, pannus covering the discs’ surface was found. A biological aortic prosthesis was reimplanted without complications.Case study 2The second patient was an 87-year-old woman with arterial hypertension, persistent atrial fibrillation, and COPD, whose past medical history included gastric ulcer disease and ischemic stroke. As in the case of the first patient, she was admitted due to valvular prosthesis dysfunction. Preoperative transthoracic echocardiography revealed an obstruction of the posterior prosthetic disc and significant aortic regurgitation. Transesophageal echocardiography and fluoroscopy confirmed the prosthetic dysfunction. During the operation, a thrombus growing around a minor pannus was found. The thrombus and pannus were removed, and normal functionality of the prosthetic valve was restored.ConclusionsPrecise and modern diagnostic methods facilitated selection of the treatment method. However, the intraoperative view also seems to be crucial in individualizing the surgical approach.

Beyond PARTNER: appraising the evolving trends and outcomes in transcatheter aortic valve replacement.

Transcatheter aortic valve replacement (TAVR) has become the preferred treatment in patients with symptomatic severe aortic stenosis deemed to be at prohibitive or high risk for surgical aortic valve replacement. With evolving technology, improving practices and patient selection, outcomes in TAVR have improved. In the not so distant future, TAVR may become an alternative to surgical aortic valve replacement even for patients who are not at high risk for open surgery. However, issues such as stroke, paravalvular leak and pacemaker need remain, and the unknown limitations of TAVR, including durability and undefined options for reintervention for prosthesis dysfunction, must be addressed before this therapy can be extended to younger, lower risk patients.

Unsuspected Aortic Dissection in Patient with Diagnosis of Prosthesis Aortic Valve Dysfunction

or thrombus was seen on the prosthesis but an intimal flap on the aortic wall was found. So the diagnosis of chronic Stanford type A aortic dissection was done. The Aortic dissection involved only the ascending aorta and the proximal part of the aortic arch. We found two tears in this part of the ascending aorta and the descending was free of dissection. In the light of that we suppose Abstract On March 2012 a 74-year-old woman was admitted to our hospital for acute pulmonary oedema. In 1994 she had undergone aortic valve replacement with a Bicarbon 23A and mitral valve repair (commissurotomy) for mitral valve stenosis Auscultation revealed normal prosthetic valve opening and closing clicks and a grade 2/6 ejection systolic murmur. TTE showed an intermittent aortic prosthesis dysfunction with mean (24 mm Hg) and peak (100 mm Hg) aortic gradients. They were higher than previous values recorded one month before. While the diagnosis of an intermittent aortic prosthesis valve dysfunction was done, the patient was admitted to the operating theatre where she had an aortic and mitral valve replacement. An aortotomy was done and an intimal flap on the aortic wall was found. After the operation the patient had an uncomplicated recovery and she was discharged on her 7th postoperative day. Ten months later, on follow up, she was in good condition with no valve dysfunction.

LONG-TERM Results FOLLOWING SURGICAL TREATMENT OF PARAVALVULAR LEAK IN THE AORTIC AND MITRAL POSITION

Periprosthetic leak (PPL) is the most common non-structural prosthesis dysfunction following heart valve replacement. Symptomatic PPL requires reintervention. However, there is a paucity of data regarding outcomes after surgical treatment of PPL. The aim of this study was to determine immediate results and long-term outcomes following surgical management of aortic and/or mitral PPL. Between 1995 and 2012, 214 patients underwent primary surgical repair (n=148) or valve replacement (n=66) for an aortic and/or mitral PPL at our institution. Of these, 128 (60%) had PPL in the mitral position, 77 (36%) had PPL in the aortic position and 9 (4%) had PPL on both valves. Mean follow-up was 5.3 ± 4.6 years. Seventeen (8%) patients were lost to follow-up after surgery. Mean age at surgery was 62 ± 12 years and 128 (60%) patients were male. Primary indication for surgery was congestive heart failure in 91 (71%) patients with mitral PPL, 65 (84%) patients with aortic PPL and 5 (56%) patients with double valve PPL. Other indications included severe hemolysis in 34 (16%) patients and endocarditis in 4 (2%) patients. The most frequent site of mitral PPL was at the posteromedian commissure and the most common site for aortic PPL was the non-coronary sinus. Operative mortality occurred in 9 (4%) patients (6 [5%] in mitral, 2 [3%] in aortic and 1 [14%] in double valve repairs). Survival at 1, 5 and 10 years was 88 ± 2%, 74 ± 3% and 60 ± 5%, respectively. Freedom from NYHA ≥ III was 93 ± 3%, 79 ± 6 % and 58 ± 8% at 1, 5 and 10 years, respectively. Freedom from PPL recurrence was 98 ± 2 %, 86 ± 4% and 66 ± 6% at 1, 5 and 10 years respectively. There was a trend towards better freedom from PPL recurrence in patients who underwent primary repair compared to valve replacement, but this difference was not statistically significant (p=0.17). In patients who suffered from PPL recurrence, the new leak occurred in the same location as the previous surgery in 11 (39%) patients. Life expectancy after surgical treatment of PPL is suboptimal. However, the freedom from PPL is acceptable and there is a trend towards better durability with primary repair. This study highlights the need for clearer guidelines for the management of PPL.

Need for a standardized protocol for stress echocardiography in provoking subaortic and valvular gradient in various cardiac conditions.

(Semi) supine exercise testing has an established role in the evaluation of patients with valvular heart disease and can help clinical decision making. Stress echocardiography has the advantages of its wide availability, low cost, and versatility for the assessment of disease severity. However, exercise-induced changes in valve hemodynamics, left ventricular outflow obstruction and pulmonary artery pressure depended on load variation. Changing position from supine to upright rapidly decreases load conditions for the ventricles. Therefore several cardiac centers have proposed exercise stress echocardiography in the upright position with gradient monitoring sometimes also in post-exercise recovery. Doppler measurement of subaortic gradient has been a very helpful and informative examination in several heart diseases (especially in hypertrophic cardiomyopathy, valve heart diseases, prosthesis dysfunction).

Simultaneous transapical aortic and mitral valve‐in‐valve implantation for double prostheses dysfunction: Case report and technical insights

Transcatheter "Valve-in-Valve" implantation (ViV) has shown promising results in high-risk patients suffering from structural valve deterioration (SVD) of a previously implanted heart valve bioprosthesis. We present a case of a 68-year-old woman with a history of three previous cardiac operations on the aortic and mitral valve. At the time of admission she was severely symptomatic due to a simultaneous SVD of a 23 mm aortic and of a 29 mm mitral St. Jude Biocor bioprosthesis. Because of the history of several cardiac operations and to her comorbidities, the patient was considered with an extremely high surgical risk profile and was therefore scheduled for double concomitant mitral and aortic ViV. Through a trans-apical approach, the patient underwent 23 and 29 mm Edwards Sapien XT implantation in the aortic and mitral bioprosthesis, respectively. The procedure was uneventful as well as the following hospital stay. At 6-months follow-up the patient is in NYHA class I. Echocardiography shows that the aortic bioprosthesis has no leak and the mean gradient is 20 mm Hg while the mitral valve has mild leak and maximum and mean gradients are 21 and 10 mm Hg, respectively. The three main technical aspects that should be carefully considered in double concomitant ViV are: sequence of valve deployment (whether to implant the mitral or the aortic valve first), choice of access and valve sizing. In conclusion, double simultaneous trans-apical mitral and aortic ViV is technically feasible. © 2014 Wiley Periodicals, Inc.

The Odyssey of TAVR from concept to clinical reality.

On 16 April 2002, my colleagues and I performed, in an inoperable and desperately ill man with critical calcific aortic stenosis (AS), the first clinical percutaneous implantation of an aortic valve bioprosthesis. As of 2013, more than 80,000 patients have been treated; and transcatheter aortic valve replacement (TAVR), so strongly criticized by all the experts throughout the early years, continues to grow in parallel with its constant technological improvements. Transcatheter aortic valve replacement can now be recognized as a medical breakthrough. It is a revolutionary technology that meets an unfulfilled clinical need for a common disease, is validated by rigorous evidence-based studies, and is applicable worldwide. We report here the main phases of this 20-year odyssey and briefly consider the prospects of TAVR, which remains in continuous development.

0076: Atrial fibrillation an uncommon cause of acute coronary syndrom due to coronary embolism: About 12 cases

Atrial fibrillation is a common entity and can be associated with thromboembolic complications as many as 18% of patients per year. A coronary thromboembolus with subsequent myocardial infarction, however, is rare. We conducted a retrospective descriptive study of 12 patients hospitalized for myocardial infarction with angiographically normal coronary arteries and atrial fibrillation. This study aims to investigate the epidemiological, clinical, and prognostic factors. We conclude that the prevalence of these ACS was 0.56%. The average age was 57 years with a female predominance. Family history of early coronaropathy was the most frequently risk factor (33%), followed by Smoking (16%), dyslipidemia (16%), obesity (16%) and hypertension (8%). Diabetes was not found in any patient. These patients had an ST elevation myocardial infarction (STEMI) in 16% of cases vs 84% without ST elevation MI. The lateral location was the most prevalent in 41% of cases. The mean peak of troponin was 8.6ng/ml. The left ventricular dysfunction was detected in 5 cases. The echocardiography showed a case of mitral valve prosthesis dysfunction, a case of hypertrophic cardiomyopathy. Aortic and mitral valvulopathy was detected in 5 cases and an excellent hemodynamic profile was found in two cases. The trans esophageal echocardiography showed 5 cases of left intra auricular thrombus. The coronarography was normal in all patients. They received the basic treatment of acute coronary syndrom. Atrial fibrillation wasn’t tolerate in one case requiring pharmacologic cardioversion with good evolution. Hyperthyroidism was detected in two patients and required antithyroid therapy. Coronary artery thromboembolism as a nonatherosclerotic cause of acute coronary syndrom is a rare finding with unknown prevalence. The cardiologist should be aware of possible coronary artery embolism when the angiographic images are typical together with important thromboembolic risk factors.

A rare case of two mechanisms of prosthetic valve dysfunction in the same patient

Prosthetic valve dysfunction is a significant clinical event. Determining its etiological mechanism and severity can be difficult. The authors present the case of a 50-year-old man, with two mechanical valve prostheses in aortic and mitral positions, hospitalized for decompensated heart failure. He had a long history of rheumatic multivalvular disease and had undergone three heart surgeries.On admission, investigation led to a diagnosis of severe dysfunction of both mechanical prostheses with different etiologies and mechanisms: pannus formation in the prosthetic aortic valve and intermittent dysfunction of the mitral prosthesis due to interference of a ruptured chorda tendinea in closure of the disks. The patient was reoperated, leading to significant improvement in functional class.

Invited Commentary

It would be easy to dismiss the study by Ellensen and colleagues [1Ellensen V.S. Andersen K.S. Vitale N. Davidsen E.S. Segadal L. Haaverstad R. Acute obstruction by pannus in patients with aortic Medtronic-Hall valves: 30 years of experience.Ann Thorac Surg. 2013; 96: 2123-2128Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar] as one of only historical interest, given that the Medtronic-Hall valve is no longer in use. The valve itself is an elegant design but is not relevant in today's “bileaflet world.” This comprehensive data set, however, gives us insight into a complication of mechanical valves common to all in character, albeit uncommon in occurrence: pannus formation.The incidence of pannus causing acute dysfunction in this study was 0.7/1,000 patient-years. This may be something of an underestimate, given that some pannus might occur causing stenosis without overt valve failure, even given a single-disc design. It is also conceivable that differences in the composition of the sewing rings could impact its development. Still, these data give us a reasonable estimate of the risk of pannus formation in the setting of a mechanical valve, a complication I always mention to a patient choosing a prosthesis but one for which I have not had handy number.The findings in this study also alert us to the serious nature of this complication, with one-quarter of individuals dying before surgical intervention could be accomplished and 2 dying during the reoperative procedure, for an overall mortality rate of 33%. It is unfortunate that the only risk factor identified is an unmodifiable one: female gender.Unfortunately, the details of suture technique, including use or nonuse of pledgets, were incomplete as was information on supraannular vs intraannular implantation, so the authors cannot give us technical advice for prevention. This leaves us with only the admonition to proceed without delay to definitive diagnostic and therapeutic measures when the diagnosis is suspected. Surely, that is of value to us all. It would be easy to dismiss the study by Ellensen and colleagues [1Ellensen V.S. Andersen K.S. Vitale N. Davidsen E.S. Segadal L. Haaverstad R. Acute obstruction by pannus in patients with aortic Medtronic-Hall valves: 30 years of experience.Ann Thorac Surg. 2013; 96: 2123-2128Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar] as one of only historical interest, given that the Medtronic-Hall valve is no longer in use. The valve itself is an elegant design but is not relevant in today's “bileaflet world.” This comprehensive data set, however, gives us insight into a complication of mechanical valves common to all in character, albeit uncommon in occurrence: pannus formation. The incidence of pannus causing acute dysfunction in this study was 0.7/1,000 patient-years. This may be something of an underestimate, given that some pannus might occur causing stenosis without overt valve failure, even given a single-disc design. It is also conceivable that differences in the composition of the sewing rings could impact its development. Still, these data give us a reasonable estimate of the risk of pannus formation in the setting of a mechanical valve, a complication I always mention to a patient choosing a prosthesis but one for which I have not had handy number. The findings in this study also alert us to the serious nature of this complication, with one-quarter of individuals dying before surgical intervention could be accomplished and 2 dying during the reoperative procedure, for an overall mortality rate of 33%. It is unfortunate that the only risk factor identified is an unmodifiable one: female gender. Unfortunately, the details of suture technique, including use or nonuse of pledgets, were incomplete as was information on supraannular vs intraannular implantation, so the authors cannot give us technical advice for prevention. This leaves us with only the admonition to proceed without delay to definitive diagnostic and therapeutic measures when the diagnosis is suspected. Surely, that is of value to us all. Acute Obstruction by Pannus in Patients With Aortic Medtronic-Hall Valves: 30 years of ExperienceThe Annals of Thoracic SurgeryVol. 96Issue 6PreviewAcute dysfunction of mechanical aortic valve prostheses is a life-threatening adverse event. Pannus overgrowth, which is fibroelastic hyperplasia originating from the periannular area, is one cause of dysfunction. The aim of this study was to determine the annual incidence of readmittance resulting from acute obstruction caused by pannus during 30 years of observation in patients with Medtronic-Hall aortic valve prostheses and to analyze the risk factors associated with pannus development. Full-Text PDF

Um caso raro de dois mecanismos de disfunção protésica no mesmo doente

Prosthetic valve dysfunction is a significant clinical event. Determining its etiological mechanism and severity can be difficult. The authors present the case of a 50-year-old man, with two mechanical valve prostheses in aortic and mitral positions, hospitalized for decompensated heart failure. He had a long history of rheumatic multivalvular disease and had undergone three heart surgeries. On admission, investigation led to a diagnosis of severe dysfunction of both mechanical prostheses with different etiologies and mechanisms: pannus formation in the prosthetic aortic valve and intermittent dysfunction of the mitral prosthesis due to interference of a ruptured chorda tendinea in closure of the disks. The patient was reoperated, leading to significant improvement in functional class.

Long-term follow-up of stentless prosthesis

BackgroundStentless prostheses have an interesting hemodynamic performance when compared to stented prostheses and are recommended in cases of small aortic annulus. Materials and methodsFrom January 1996 to January 2004, 138 patients suffering from aortic disease, underwent aortic valve replacement.•Group A: 93 patients underwent stentless aortic valve implantation [stentless Biocor (Biocor Industria e Pesguisa Ltda, Belo Horizonte, Brazil) and stentless Sorin (Sorin Group, Saluggia, Italy)].•Group B: 45 patients underwent stented aortic valve implantation (stented Biocor). Patients were assessed by clinical evaluation and echocardiography after a mean follow up of 124.5±58.2 months. ResultsThere was a significant difference in terms of time of extracorporeal circulation and aortic cross clamp. The actuarial survival at 4, 8, 12, and 15 years is 77%, 50%, 21%, and 18%, respectively. Freedom from reoperation at 4, 8, 12, and 14 years was 92%, 83%, 73%, and 63%, respectively. Freedom from all events, death, and reoperation at 4, 8, 12, and 14 years was 70%, 39%, 13%, and 8%, respectively. There is no statistical difference among the two groups in terms of actuarial survival, freedom from reoperation, and freedom from re-hospitalization for prosthesis-related causes. DiscussionThere was a significantly higher incidence of pacemaker implantation in Group A and the causes are not known. The rate of freedom from reoperation is high in both groups for the patients who remained alive. There was no statistical difference about prosthesis dysfunction between the two groups. The higher incidence of death in Group A cannot be explained by causes related to the prosthesis because there is no difference in terms of causes of death. Rates of reoperation did not differ between the two groups. ConclusionsThe results obtained with stentless prostheses are encouraging even in long-term follow-up.

Outcomes of Patients Undergoing Third-Time Aortic or Mitral Valve Replacement

Third-time valve surgery is rare and to date little is known about the surgical outcome. We reviewed our experience with third-time aortic valve replacement (AVR) and third-time mitral valve replacement (MVR) during an eight-year period. From 2001 to 2013, 32 patients were referred for third-time AVR or third-time MVR to our institution. In this retrospective analysis, patients were evaluated for postoperative morbidity including: hemodialysis, cerebrovascular event, pacemaker implantation, and 30-day and mid-term mortality. Third-time replacement was for failed aortic valves in 20 (62.5%) patients and for failed mitral valves in 12 (37.5%) patients. Patients' mean age at the time of surgery was 56.3 ± 19 years. The mean interval between the first and the second procedure was 10 ± 7.8 years and between second and third replacement 7.3 ± 5.6 years. The failed prostheses included nine (28%) bioprostheses and 23 (72%) mechanical prostheses. The reasons for replacement were: infective valve endocarditis (31.3%), prosthesis dysfunction (37.3%), and paravalvular leakage (26%). The 30-day mortality was 18.8% and during follow-up was 31.3%. Hemodialysis was needed for eight patients (25.8%), pacemaker implantation for eight patients (25.8%), and cerebrovascular event occurred in four patients (13.3%). In patients with prosthetic valve endocarditis (n = 10), 30-day and overall mortality were 11.1% and 30%, respectively. Third-time aortic or mitral valve replacement is a rare procedure but accompanied with high morbidity and mortality, especially in patients with prosthetic valve endocarditis.

Acute Obstruction by Pannus in Patients With Aortic Medtronic-Hall Valves: 30 years of Experience

Acute dysfunction of mechanical aorticvalve prostheses is a life-threatening adverse event. Pannus overgrowth, which is fibroelastic hyperplasia originating from the periannular area, is one cause of dysfunction. The aim of this study was to determine the annual incidence of readmittance resulting from acute obstruction caused by pannus during 30 years of observation in patients with Medtronic-Hall aortic valve prostheses and to analyzethe risk factors associated with pannus development. From 1982 to 2004, 1,187 patients in our department underwent aortic valve replacement with Medtronic-Hall mechanical monoleaflet valve prostheses. As of December 31, 2012, 27 of these patients (2.3%) had presented with acute valve dysfunction caused by pannus obstruction. The annual incidence of pannus was 0.7 per 1,000. The median time from the primary operation to prosthetic dysfunction was 11.1 years (range, 1.2 to 26.8 years). Of the 20 patients who underwent reoperation, 2 died. Seven patients died before reoperation. Women had a higher risk for the development of obstructing pannus, and patients with pannus obstruction were younger. Valve size was not an independent risk factor. Women and younger patients are at higher risk for pannus development. When acute dysfunction by pannus is suspected in a mechanical aortic valve, an immediate echocardiogram and an emergency aortic valve replacement should be carried out because of the potential of a fatal outcome.

Freestyle root replacement for complex destructive aortic valve endocarditis

In destructive aortic valve endocarditis with abscess formation in the root, homografts are used more often than xenografts. Because we had reliable perioperative results with Freestyle (Medtronic Inc, Minneapolis, Minn) xenograft root replacement in these complex patients, we analyzed the long-term outcome in this high-risk indication. Of 126 consecutive patients with aortic valve endocarditis treated by surgery from 1997 to 2012, 32 (25.4%) received a Freestyle aortic root replacement for severe, destructive valve endocarditis and were studied retrospectively with approval of the local ethical committee. Perioperative complications, recurrence of endocarditis, and long-term morbidity and mortality were analyzed. The follow-up period was 3 months to 11.5 years. Indication for surgery was native (n=9) and prosthetic valve endocarditis (n=23). In 18 patients, concomitant procedures were performed: coronary bypass (n=9), additional valve surgery (n=6), and ascending aortic surgery (n=7). Thirty-day mortality was 19.4% (n=6). There were no instances of technical failure requiring modification of the surgical strategy or reoperation for anastomotic bleeding. Actuarial survival at 5 and 10 years was 61.9% and 54.2%, respectively. Freedom from death, reoperation for prostheses dysfunction, and recurrence of endocarditis as the composite end point at 5 and 10 years was 56.3% and 53.1%, respectively. The Freestyle root was used successfully with no technical complications in all patients with most severe destructive aortic root endocarditis. In view of this complex patient population, short- and long-term results make this conduit a reliable choice for treatment of this condition.

Carpentier-Edwards Pericardial Valve in the Aortic Position: 25-Years Experience

The Carpentier-Edwards pericardial valve was designed to minimize structural valve deterioration. Excellent durability and low incidence of valve-related complications have been reported. The objective of the present study was to analyze clinical results after 25 years of experience with this valve implanted in the aortic position. The effect of patient age at the time of surgery was also evaluated. This is a retrospective cohort study of 2,405 patients from November 1981 to March 2011. Primary outcomes of interest were survival and freedom from major adverse effects such as thromboembolic, endocarditis, and reoperation. Sixty percent were male, with a mean age of 71 ± 9 years old. Actuarial survival rates including early deaths averaged 78% ± 2%, 55% ± 2%, and 16 % ± 2% after 5, 10, and 20 years of follow-up, respectively. The freedom rate of valve reoperation for prosthesis dysfunction and all other causes averaged 98 % ± 0.2%, 96% ± 1%, and 67% ± 4% at 5, 10, and 20 years. Patients younger than 60 years of age had a 15-year survival averaging 54% ± 5% compared with patients aged between 60 and 70 years of age averaging 46% ± 3% and with patients older than 70 years of age averaging 28% ± 3% (p = 0.001). Survival at 5, 10, and 20 years for patients who had concomitant CABG [coronary artery bypass grafting] were 78% ± 1%, 55% ± 2%, and 9% ± 3% compared with no concomitant CABG (84% ± 1%, 62% ± 2%, and 22% ± 3% (p < 0.001)). Carpentier-Edwards pericardial valve implantation in the aortic position is secure and durable. The effects of age influence reoperation rate and survival as well as a concomitant coronary artery bypass procedure.

Minimally invasive tricuspid valve surgery in patients at high risk

Reports of minimally invasive tricuspid valve operations are rare, and results are often contradictory. This study analyzes our 5-year experience with minimally invasive tricuspid valve operations in high-risk patients. Between November 2005 and December 2011, tricuspid valve surgery using a nonsternotomy minimally invasive technique was performed in 64 patients (19 male, 45 female; mean age, 63.2±12.8years). Mean preoperative European System for Cardiac Operative Risk Evaluation was 7.3±2.9, and predicted mortality was 11.6%±11.7%. Tricuspid valve regurgitation cause was functional in 36 patients (56.2%), endocarditis in 2 patients (3.1%), and rheumatic in 24 patients (37.5%). Two patients (3.1%) showed prosthesis dysfunction. Forty patients (62.5%) had undergone previous cardiac surgery. Tricuspid valve repair was performed in 35 patients (54.7%). Tricuspid valve replacement with bioprosthesis was performed in 27 patients (42.2%), and the remaining 2 patients (3.1%) underwent bioprosthetic replacement. Concomitant procedures (48) included mitral valve surgery (42 patients), atrial septal defect closure (5 patients), and myxoma exeresis (1 patient). Conversion to sternotomy occurred in 1 patient (1.6%). Overall hospital mortality was 7.9%. Stroke occurred in 1 patient (1.6%), and 5 patients underwent reoperation for bleeding (7.8%). Mean follow-up time was 21±16months (range, 1-59months) and 100% completed. Cumulative Kaplan-Meier estimated 5-year survival was 81.3%, and 5-year freedom from reoperation was 100%. The heart-port-based minimally invasive approach seems to be safe, feasible, and reproducible in case of tricuspid valve operations. It ensures low perioperative morbidity, moderate to low rates of tricuspid regurgitation recurrence, and low late mortality. It also seems to have an added value in case of reoperative procedures.

Localized Transvalvular Pressure Gradients in Mitral Bileaflet Mechanical Heart Valves and Impact on Gradient Overestimation by Doppler

It has been reported that localized high velocity may be recorded by continuous-wave Doppler interrogation through the smaller central orifices of bileaflet mechanical heart valves (BMHV) and that this may result in overestimation of the transvalvular pressure gradient (TPG). However, the prevalence and clinical relevance of this phenomenon remain unclear, particularly for BMHVs in the mitral position. The objective of this in vitro study was to assess the presence and magnitude of localized high velocity in mitral BMHVs as well as its impact on TPG overestimation by Doppler. Nine BMHVs were tested under nine different flow conditions (volumes and flow waveforms) in a simulator specifically designed to assess mitral valve hemodynamics. Flow velocity was measured at three different locations (leading edge, midleaflets, and trailing edge) within the central and lateral orifices of the BMHVs using pulsed-wave Doppler. TPG was measured by pulsed-wave and continuous-wave Doppler and by catheterization. The maximum flow velocity occurred within the central orifice of the BMHV in 61% of the 81 tested conditions. This locally higher velocity within the central orifice predominantly occurred at the leading edge of the prosthesis. Doppler overestimated mean TPG by an average of 5% to 10% compared with catheterization. The magnitude of the localized high velocity and ensuing overestimation of TPG by Doppler was more important at higher mitral flow volumes (P < .0001) as well as in BMHVs with smaller internal ring diameters (P < .0001). This study shows that the flow velocity distribution within the three orifices of mitral BMHVs is not uniform and that higher velocity occurs more frequently, but not always, within the inflow aspect of the central orifice. In most mitral BMHVs and flow conditions, this localized high-velocity phenomenon causes small overestimation of TPGs (<2 mm Hg and <10%) by Doppler and is thus not clinically relevant. However, in small mitral BMHVs exposed to high flow rates, the overestimation of TPG due to localized high velocity could become more important and overlap with the range of gradients found in patients with prosthesis dysfunction or prosthesis-patient mismatch.

CryoLife O'Brien aortic stentless prosthesis reoperations: clinical results and morphologic findings

The CryoLife O'Brien (CLOB) stentless porcine aortic prosthesis has shown limited long-term durability, but its deterioration mechanisms have not yet been identified. The aim of this study was to review our experience with CLOB reoperations and to investigate the pathobiology of structural valve deterioration (SVD). Between March 1996 and December 2010, 35 patients underwent reoperation 82 ± 43 months after a CLOB implant. Patient records were retrospectively reviewed and follow-up was 100% complete. Nine valves explanted for SVD underwent pathological study. Nineteen patients (54%) were operated on urgently for prosthetic valve replacement. No intraoperative technical complications occurred, and only one patient underwent aortic root replacement. One patient (3%) died in-hospital. Prosthesis dysfunction was due to SVD in 27 patients, caused by cusp commissural tearing in 22. All the nine explanted valves submitted to pathological examination showed calcifications and lipid insudation. At histology, eight prostheses disclosed cholesterol clefts and all showed a chronic inflammatory infiltrate. Transmission electron microscopy disclosed the presence of calcific deposits on cell debris and collagen fibres and confirmed the presence of cholesterol clefts. After a mean follow-up of 50 ± 33 months, survivals at 1, 5 and 7 years were 91 ± 5, 56 ± 9 and 38 ± 13%, respectively. The CLOB reoperation is a feasible procedure, with satisfactory postoperative and mid-term survival results. Cusp tears, due to lipid and calcium deposits mostly targeting the commissures, seem to be the most important mechanism of SVD, resulting even in acute prosthetic incompetence and urgent reoperation.

Comprehensive Hemodynamic Assessment of 368 Normal St. Jude Medical Mechanical Mitral Valve Prostheses Based on Early Postimplantation Echocardiographic Studies

Two-dimensional and Doppler-derived echocardiographic data on normal St. Jude Medical mechanical mitral valve prosthesis function have been reported but remain limited. Comprehensive retrospective two-dimensional and Doppler echocardiographic assessment of 368 normal St. Jude Medical mechanical mitral valve prostheses was performed early after implantation. The early postimplantation hemodynamic profiles of 98 patients were compared with profiles obtained by follow-up transthoracic echocardiography performed <13 months after implantation. Using mean ± 2 SDs to define the normal distribution of values for Doppler-derived hemodynamic variables, the calculated normal ranges of values were as follows: mean gradient, 2 to 7 mm Hg; peak early mitral diastolic velocity (E velocity), 1.1 to 2.4 m/sec; time-velocity integral of the mitral valve prosthesis (TVIMVP) 20 to 50 cm; ratio of the TVIMVP to the time-velocity integral of the left ventricular outflow tract (TVILVOT), 0.9 to 2.5; pressure half-time, 35 to 99 msec; and effective orifice area, 1.12 to 3.24 cm(2). Patients with severe prosthesis-patient mismatch (ie, indexed effective orifice area ≤ 0.9 cm(2)/m(2)) had significantly higher mean gradients, E velocity, TVIMVP, and TVIMVP/TVILVOT. There was a trend for longer pressure half-times for patients with severe prosthesis-patient mismatch than for patients without severe prosthesis-patient mismatch, but none of these patients had pressure half-times > 130 msec. Among the 98 patients with follow-up transthoracic echocardiography <1 year after implantation, no significant differences were observed between early postimplantation findings and follow-up hemodynamic profiles. This study establishes parameters (mean ± 2 SDs) defining the distribution of values for Doppler-derived hemodynamic data with normal St. Jude Medical mechanical mitral valve prostheses. Prostheses with hemodynamic values outside these parameters are likely dysfunctional; however, prosthesis dysfunction may be present even when hemodynamic values are within these ranges.