Aortic valve hydrodynamics: considerations on the absence of sinuses of Valsalva.

BACKGROUND AND AIM OF THE STUDY: The study aim was to compare the hydrodynamics of the Carpentier-Edwards Magna 21 (CEM) and St. Jude Medical Biocor-Epic-Supra 21 (SJME) valves at increasing stroke volume and pulse rate in two different aortic conduits, namely straight and with sinuses of Valsalva present. METHODS: Both valve types were tested in the aortic chamber of the Sheffield pulse duplicator, at rates of 70, 80 and 90 beats/min, and stroke volumes of 50 and 60 ml. The systolic and diastolic performances were each recorded. The leaflet coaptation time, ventricle isovolumetric time and maximum instantaneous flow rate were also recorded. RESULTS: Regardless of the aortic conduit, CEM valves showed a significantly lower gradient than SJME valves (p < 0.05), and a significantly larger effective orifice area (EOA) (p < 0.05); the latter parameter was unaffected for both valves, at an increasing pulse rate (p > 0.05). The maximum transvalvular flow velocity was significantly higher in the straight conduit for both valves (p < 0.05). With regards to diastole, the SJME valve showed the lowest regurgitant volume (p < 0.05). The leaflet coaptation time was significantly shorter for the SJME valve than for the CEM valve (p < 0.05), but when tested in a straight conduit it was shortened significantly for both valves (p < 0.05). CONCLUSION: An absence of the sinuses of Valsalva may modify the diastolic and systolic behaviors of the tissue valve leaflets by reducing the time required for leaflet coaptation, and increasing the valve closing volume and maximum transvalvular flow velocity. It is speculated that these hydrodynamic changes may increase the working stress on the valve tissue, leading to possible premature structural valve deterioration.

Carpentier-Edwards Magna ease versus Magna valves: a comparison of in-vitro valve hydrodynamic performance.

BACKGROUND AND AIM OF THE STUDY: Previous studies have shown that the Carpentier-Edwards Magna (CEM) valve is an excellent bioprosthesis in terms of its systolic performance; indeed, it has been described as 'a stented valve with stentless performance'. However, valve performance is not only a matter of gradients; it is also necessary to evaluate the diastolic-phase performance. Previous in-vitro studies have shown that the CEM has an excessive total regurgitant volume. Hence, the study aim was to compare the hydrodynamics of the CEM, with the newly evolved version of this valve, the CEM Ease (CEME). METHODS: The CEM and CEME valves (both 21 mm) were tested in the aortic chamber (23 mm diameter) of the Sheffield pulse duplicator. The tests were carried out at increasing pulse rates (PR; 70-100 beats/min), and at each pulse rate the valve was tested at different stroke volumes (SVs; 45-65 ml). The forward-flow pressure drop, closing leakage volumes and effective orifice area (EOA) were recorded. RESULTS: The CEM and CEME valves showed a comparable systolic-phase performance, there being no significant differences in terms of transvalvular gradient, EOA and stroke work loss, regardless of the PR and SV. In fact, the new CEME exhibited a significantly improved diastolic performance, with the total regurgitant volume being significantly lower, due especially to a reduced leakage volume and, to a lesser extent, a reduced closing volume. CONCLUSION: The study results indicated that the new CEME valve would maintain the excellent systolic performance of the previous CEM model, but with a significantly improved diastolic performance.

The changing hydrodynamic performance of the decellularized intact porcine aortic root: considerations on in-vitro testing.

BACKGROUND AND AIM OF THE STUDY: The most effective method for decellularization of the intact porcine aortic root remains controversial. Additionally, the hydrodynamic effect that such treatment may have on aortic roots has never been previously investigated. The study aim was to compare the in-vitro hydrodynamic performances of intact porcine aortic roots, both before and after decellularization treatment. METHODS: Fifteen fresh porcine aortic roots were tested in the aortic chamber of the Sheffield pulse duplicator (SPD). For study purposes, the roots were first sutured to a silicone aortic root and then hydrodynamically tested. After in-vitro testing, the fresh porcine aortic roots, while still fixed within the silicone root, were decellularized according to various protocols (TRI-COL, TRI-DOC, sodium dodecyl sulfate (SDS) 0.03%, and SDS 0.1%). After decellularization, the valve roots were re-tested, adopting identical testing conditions. Forward flow pressure drop, closing leakage volumes, effective orifice area (EOA), and stroke work loss were each monitored. Three roots, used as a control group, were tested in identical fashion before and after storage (without decellularization) for comparative purposes. RESULTS: The TRI-COL- and TRI-DOC-treated porcine aortic roots showed significantly lower transvalvular gradients, lower stroke work loss, lower valve resistance, and higher EOA than fresh intact porcine roots. In contrast, SDS 0.1%-treated porcine aortic roots showed opposing results, with the transvalvular gradients, stroke work loss and valve resistance each higher, and the EOA lower, than pre-treatment values. SDS 0.03% treatment had no significant effect on the hydrodynamic performance. After decellularization in all treatment groups, the diastolic parameters, total regurgitant volume and valve closing volume were each non-significantly increased. The aortic roots used as a control group showed similar results before and after storage. CONCLUSION: Based on these results using the SPD, all treatments except for SDS 0.03% modified the systolic and diastolic functions of intact porcine aortic roots.

In-vitro testing of three totally supra-annular bileaflet mechanical valves: hydrodynamics in the Sheffield pulse duplicator.

BACKGROUND AND AIM OF THE STUDY: In-vivo echocardiographic studies are limited by several confounding factors and technical pitfalls, and consequently the hypothetical differential hydraulic behavior between different prosthetic heart valves has not been identified. However, for surgeons it is essential to know the functional and geometric characteristics of the prostheses to be used. Herein, the in-vitro performance of two new supra-annular bileaflet prostheses--the Medtronic Advantage Supra and Sorin Bicarbon Overline--was compared with that of the 21-mm St. Jude Medical (SJM) Regent valve. METHODS: Three high-performance, production-quality prostheses, including the sewing-ring cuffs, were tested in the aortic chamber of a Sheffield pulse duplicator. The sizes of the prostheses which fitted the 21-mm valve holder were: 21 mm Advantage Supra Medtronic; 19 mm SJM Regent, and 18 mm Sorin Bicarbon Overline. The tests were carried out at a fixed pulse rate (70 beats/min), and at increasing cardiac output (CO) of 2, 4, 5, and 7 l/min. Forward-flow pressure drop, total regurgitant volume, closing and leakage volumes, effective orifice area (EOA) and stroke work loss (SWL) were recorded while the valve was operated at each CO. RESULTS: The SJM Regent and Sorin Bicarbon Overline valves each showed, at increasing CO, significantly lower mean and peak gradients. The calculated EOA and SWL were significantly better with the SJM Regent and Sorin Bicarbon Overline prostheses. The Medtronic Advantage Supra valve showed comparable results only while performing at 2 l/min CO. With regards to the regurgitant fraction, lowest values were observed with the Medtronic Advantage Supra valve. CONCLUSION: This hydrodynamic evaluation model allowed a comparison to be made of the efficiency of recently commercialized bileaflet prostheses, among which the older SJM Regent and the newer Sorin Bicarbon Overline valves demonstrated the best performances.

Infective endocarditis in bicuspid aortic valve: atrioventricular block as sign of perivalvular abscess.

A 46-year-old man presenting with fever, peripheral edema, and chest pain was admitted to the emergency department. Electrocardiogram showed sinus tachycardia and first-degree atrioventricular block. Transesophageal echocardiogram showed infective endocarditis in bicuspid aortic valve, complicated with severe aortic regurgitation, ring abscess, and sinus-of-Valsalva aneurysm extending to mitroaortic fibrous continuity. The patient, who was unaware of his bicuspid aortic valve condition, reported having undergone an orthodontic procedure complicated with dental abscess 1 month prior, which was treated with combined clavulanate-amoxicillin antibiotic therapy. Blood cultures were positive for Bacteroides fragilis resistant to metronidazole. Intravenous antibiotic therapy was undertaken, with rapid resolution of fever. He eventually underwent successful aortic homograft implantation and mitral valve repair with residual first-degree atrioventricular block.

Impact of Changes in Left Ventricular Ejection Fraction on Survival After Transapical Aortic Valve Implantation.

BACKGROUND: This single-center retrospective study assessed the variation of left ventricular ejection fraction (LVEF) after transapical transcatheter aortic valve implantation and its effect on survival. We also evaluated the effect of sheath diameter on LVEF. METHODS: We analyzed data of all consecutive patients who underwent transapical transcatheter aortic valve implantation with the Sapien (Edwards Lifesciences, Irvine, CA) device (and its evolutions) between 2009 and 2015. We analyzed the difference between preoperative LVEF and LVEF at discharge (ΔEF = LVEFpost-op - LVEFpre-op) and considered its interquartile range (±5%) as the cutoff. Patients were divided in three groups: (1) improved LVEF (ΔEF ≥ +5%); (2) unchanged LVEF (ΔEF -5% to +5%), and (3) worsened LVEF (ΔEF ≤ -5%). Survival was evaluated with Kaplan-Meier analysis, and logistic regression multivariable analysis was used to determine independent predictors of LVEF improvement. RESULTS: Data of 122 patients were analyzed. Patients in the three groups were distributed as follows: (group 1) 27 patients (22.1%), (group 2) 69 (56.6%), and (group 3) 26 (21.3%). The mean ΔEF was 12.7% ± 4.7% in group 1 and -10.8% ± 3.9% in group 3. The ΔEF was more likely to improve in patients with preoperative LVEF of less than 0.35 (p = 0.014). There were no significant differences in survival (p = 0.41), rehospitalization (p = 0.472), and New York Heart Association Functional Classification (p = 0.307) among the groups. The use of the smallest available sheath (18F) was not associated with a significant change of ΔEF. CONCLUSIONS: LVEF worsened in a small number of patients after transapical transcatheter aortic valve implantation, but this change was not associated with worse postoperative outcomes. Patients with a low LVEF showed better improvement. The progressive reduction of sheath diameter does not have a significant effect on LVEF changes.

A pilot study on the efficacy and safety of a minimally invasive surgical and anesthetic approach for ventricular assist device implantation.

BACKGROUND: The aim of our study was to compare 2 surgical and anesthetic approaches during ventricular assist device implantation. METHODS: 68 patients (50.4 ± 17.1 years old) were supported with the HeartWare® HVAD (32 patients) and the Jarvik 2000 VAD (36 patients) between January 2010 and August 2016. Two surgical techniques were applied: a minimally invasive approach with the aid of paravertebral-block (mini-invasive group, 41 patients) and a standard-surgical-approach with the aid of general anesthesia (27 patients). RESULTS: The minimally invasive approach allowed faster postoperative recovery by significantly reducing the duration of surgery (p<0.05), anesthesia (p<0.05), mechanical ventilation (p<0.05), inotropic support (p<0.05), ICU and in-hospital stay (p<0.05), and time to first mobilization (p<0.05). No case of epidural hematoma was observed. Eleven patients died (16%) at 30 days, 3 in the mini-invasive group (7.3%) and 8 in the invasive group (29.6%). CONCLUSIONS: Minimally invasive approaches play a substantial role in VAD surgery by facilitating faster recovery, which is important for patients at very high risk.

Early and Midterm Clinical and Hemodynamic Outcomes of Transcatheter Valve-in-Valve Implantation: Results From a Multicenter Experience.

BACKGROUND: Transcatheter valve-in-valve (VIV) implantation is an alternative option in inoperable or high-risk patients with prosthetic valve dysfunction. Aim of this retrospective multicenter study was to evaluate early and midterm clinical and hemodynamic outcomes of patients undergoing aortic (VIV-A) and mitral VIV (VIV-M). METHODS: We analyzed data of 66 procedures performed in 65 patients who underwent VIV procedures in the VIV-A and VIV-M position at 5 Italian institutions from January 2008 to May 2015. VIV-A and VIV-M were 44 (68%) and 22 (32%), respectively; 1 patient underwent combined mitroaortic VIV. Study devices were both balloon-expandable and self-expandable. Outcomes were defined according to the updated Valve Academic Research Consortium definitions. RESULTS: Overall all-cause 30-day mortality was 6% (4 patients), and it was 4.5% and 9% in VIV-A and VIV-M, respectively (2 patients in each group). Mean follow-up was 14 ± 14 months. Kaplan-Meier survival of the entire cohort at 1, 2, 3, and 4 years was 84.4% ± 4.9%, 80.5% ± 6%, 74.3 ± 8.1%, and 62% ± 13.2%, respectively. Age (hazard ratio: 1.1; 95% confidence interval: 1.0 to 1.3; p = 0.035) and diabetes (hazard ratio: 7.2, 95% confidence interval: 2.1 to 23.7; p = 0.001) were identified as independent predictors of mortality. Degenerated surgical aortic prostheses with an internal diameter (ID) less than 20 mm had significantly higher gradients if compared to prostheses with ID 21 to 23 mm and greater than 23 mm. After VIV-A, a severe stenosis (mean gradient greater than 35 mm Hg) was detected in 3 (6.8%) cases, all with ID less than 20 mm. CONCLUSIONS: VIV provides good early and midterm results in high-risk or inoperable patients with mitral or aortic bioprosthesis dysfunction. Age and diabetes are independently associated with mortality. Size of bioprosthesis ID has a significant impact on postoperative gradients.

Does sports activity enhance the risk of sudden death in adolescents and young adults?

OBJECTIVES: We sought to assess the risk of sudden death (SD) in both male and female athletes age 12 to 35 years. BACKGROUND: Little is known about the risk of SD in adolescents and young adults engaged in sports. METHODS: We did a 21-year prospective cohort study of all young people of the Veneto Region of Italy. From 1979 to 1999, the total population of adolescents and young adults averaged 1,386,600 (692,100 males and 694,500 females), of which 112,790 (90,690 males and 22,100 females) were competitive athletes. An analysis by gender of risk of SD and underlying pathologic substrates was performed in the athletic and non-athletic populations. RESULTS: There were 300 cases of SD, producing an overall cohort incidence rate of 1 in 100,000 persons per year. Fifty-five SDs occurred among athletes (2.3 in 100,000 per year) and 245 among non-athletes (0.9 in 100,000 per year), with an estimated relative risk (RR) of 2.5 (95% confidence interval [CI] 1.8 to 3.4; p < 0.0001). The RR of SD among athletes versus non-athletes was 1.95 (CI 1.3 to 2.6; p = 0.0001) for males and 2.00 (CI 0.6 to 4.9; p = 0.15) for females. The higher risk of SD in athletes was strongly related to underlying cardiovascular diseases such as congenital coronary artery anomaly (RR 79, CI 10 to 3,564; p < 0.0001), arrhythmogenic right ventricular cardiomyopathy (RR 5.4, CI 2.5 to 11.2; p < 0.0001), and premature coronary artery disease (RR 2.6, CI 1.2 to 5.1; p = 0.008). CONCLUSIONS: Sports activity in adolescents and young adults was associated with an increased risk of SD, both in males and females. Sports, per se, was not a cause of the enhanced mortality, but it triggered SD in those athletes who were affected by cardiovascular conditions predisposing to life-threatening ventricular arrhythmias during physical exercise.

Intermediate results of isolated mitral valve replacement with a Biocor porcine valve.

BACKGROUND: We analyzed the intermediate experience, survival, and prosthetic complications of patients who received the Biocor valve, a new-generation porcine valve, in the mitral position. METHODS: At the University of Padua, between May 1992 and January 2004, 154 consecutive patients (102 female and 52 male patients; mean age, 72.3 +/- 6 years; age range, 37-86 years) received 158 mitral Biocor prostheses (Biocor Industria e Pesguisa Ltda, Belo Horizonte, Brazil). Thirty-five percent of the patients had previous mitral operations, 24% had coronary artery bypass grafting, and 34.6% had other procedures. Median preoperative New York Heart Association class was III. Echocardiography was performed in 75% of the long-term survivors. Follow-up included 609.4 patient-years and was 100% complete, with a median time of 4 patient-years (range, 0.02-11.3 years). At 8 years, 20 (14%) of 142 operative survivors were still at risk. RESULTS: Early mortality was 13.6%. According to univariate analysis, New York Heart Association class III to IV, ejection fraction of less than 40%, urgency, male sex, and coronary artery bypass grafting were significant perioperative risk factors. Eight- and 10-year actuarial survival was 51.1% +/- 5.6% (40 deaths). Eight-year actuarial freedom from valve-related death, thromboembolism, anticoagulant-related hemorrhage, endocarditis, paravalvular leak, and valve-related complications were 85.2% +/- 5%, 85.7% +/- 4.4%, 92.6% +/- 3.7%, 94.1% +/- 3%, 91.8% +/- 3%, and 70.2% +/- 5.7%, respectively. Freedom from structural valve deterioration was 100%. Actual freedom from reoperation was 93.2% +/- 2.2%. By Doppler echocardiography, the peak and mean transprosthetic gradients were 15 +/- 5 mm Hg and 6.3 +/- 3 mm Hg, respectively (mean follow-up, 4.2 +/- 2.7 years). CONCLUSION: At intermediate follow-up, the Biocor prosthesis in the mitral position showed excellent results in terms of valve durability when compared with other second-generation tissue valves.

Biological versus mechanical aortic prosthesis? A nineteen-year comparison in a propensity-matched population.

BACKGROUND AND AIM OF THE STUDY: The choice of aortic valve substitutes remains controversial. Malfunction and systemic valve complications affect the results of mechanical and tissue valves. Two devices--the Sorin Monocast (tilting disk) valve and the Hancock Standard valve were compared, the study aim being to determine whether the valve model is a marker or a causal influence of poor outcome after aortic valve replacement (AVR). METHODS: Between January 1970 and January 1984, patients aged < 70 years and operated on for aortic valve disease were selected. A total of 379 patients received either Sorin (group S) valves (n = 213; median age 51 years) or Hancock Standard (group HcK) valves (n = 192; median age 50 years) (p = NS). Total follow up was 2,471 patient-years (pt-yr) for group S and 2,368 pt-yr for group HcK. Follow up was 98% complete; median duration was 15 pt-yr for group S and 13.2 pt-yr for group HcK. Propensity matching for available patient intrinsic and operative risk factors was ultimately used to investigate whether biological or mechanical valve models impact upon outcome after aortic valve surgery. Patient survival was analyzed according to the 'intention to treat' principle. RESULTS: The 30-day mortality was 7.5% for group S and 10.9% for group HcK (p = NS). The 19-year Kaplan-Meier freedom from valve-related mortality was 84% (group S) and 82% (group HcK) (p = NS), while overall survival was 42% (group S) and 35% (group HcK) (p = NS). Structural valve deterioration (SVD) was the major cause of reoperation in the HcK group. The 19-year freedom from all valve-related complications was 43% (group S) versus 19% (group HcK) (p = 0.0001). By propensity score, 61% of the valve replacements (247/405) were perfectly matched for available risk factors, with an equal distribution of risk covariates. When SVD and reoperation due to SVD were excluded, survival and freedom from all valve-related complications of the matched patients were identical between the prostheses under comparison. CONCLUSION: In this relatively young population, the Sorin valve showed a significantly lower valve-related complication rate than the Hancock Standard valve. The latter valve showed a significantly increasing rate of reoperation due to SVD, and thereby a relative inadequacy for use in younger patients. When analyzed according to an 'intention to treat' principle, the 19-year survival and freedom from valve-related complications of patients with the same propensity score for selection of either valve type were similar.

Single vs double antiplatelet therapy in acute coronary syndrome: Predictors of bleeding after coronary artery bypass grafting.

AIM: To investigate the contribution of anti-platelet therapy and derangements of pre-operative classical coagulation and thromboelastometry parameters to major bleeding post-coronary artery bypass grafting (CABG). METHODS: Two groups of CABG patients were studied: Group A, treated with aspirin alone (n = 50), and Group B treated with aspirin and clopidogrel (n = 50). Both had similar preoperative, clinical, biologic characteristics and operative management. Classic coagulation parameters and rotational thromboelastometry (ROTEM) profiles were determined preoperatively for both groups and the same heparin treatment was administered. ROTEM profiles (INTEM and EXTEM assays) were analyzed, both for traditional parameters, and thrombin generation potential, expressed by area-under-curve (AUC). RESULTS: There was no significant difference between rates of major bleeding between patients treated with aspirin alone, compared with those treated with aspirin and clopidogrel (12% vs 16%, P = 0.77). In the 14 cases of major bleeding, pre-operative classic coagulation and traditional ROTEM parameters were comparable. Conversely we observed that the AUC in the EXTEM test was significantly lower in bleeders (5030 ± 1115 Ohm*min) than non-bleeders (6568 ± 548 Ohm*min) (P < 0.0001). CONCLUSION: We observed that patients with a low AUC value were at a significantly higher risk of bleeding compared to patients with higher AUC, regardless of antiplatelet treatment. This suggests that thrombin generation potential, irrespective of the degree of platelet inhibition, correlates with surgical bleeding.

Double crisscross sternal wiring and chest wound infections: a prospective randomized study.

OBJECTIVE: We sought to assess the efficiency of 2 different sternal wiring techniques in preventing deep sternal wound infection or sternal instability. METHODS: Seven hundred patients were randomized to 2 different groups according to chest-closure techniques. Three hundred fifty patients who underwent a peristernal double crisscross wire closure were included in group X, whereas 350 patients who underwent a standard transsternal closure were included in group T. After sternal closure, the technique for wound suturing was the same for both groups, namely triple-layer sutures up to the intracutaneous skin. All data were prospectively collected and entered in our institute database. RESULTS: The 2 groups of patients were comparable for sex, age, preoperative risk factors, and operative procedures. The overall mortality rate was 4.3% in group X and 4.6% in group T. Postoperative morbidity and mortality were comparable between the 2 groups, unlike for sternal wound complications. None of the patients included in group X had superficial or deep wound complications, whereas in group T 7 (2%) patients presented with a superficial sternal wound infection, 6 (1.7%) presented with a deep chest wound infection with sternal instability requiring re-exploration (P <.05), and 3 presented with a sternal instability caused by sternum disruption without infection. Among patients with deep wound infection and sternal instability, 1 patient died, resulting in a mortality rate of 16.7%. CONCLUSIONS: The peristernal double crisscross wiring technique achieved a greater sternal stability, resulting in a lower incidence of wound infection in association with triple-layer closure of suprasternal tissues.

Long-term durability of the Hancock II porcine bioprosthesis.

BACKGROUND: Survival and prosthetic complications of patients receiving the Hancock II second-generation bioprosthesis (Medtronic, Inc, Minneapolis, Minn) in the aortic, mitral, mitral-aortic, and tricuspid positions were analyzed at 15 years' follow-up. METHODS: Between May 1983 and December 1993, 212 patients (104 men and 108 women; mean age, 63 +/- 9 years; age range, 29-81 years) received 66 aortic, 114 mitral, 26 mitral-aortic, and 6 tricuspid Hancock II valves. Thirty-one percent of patients had previous valve operations, 15% had concomitant cardiac procedures, and 87% were in New York Heart Association class III or IV. Follow-up included 1704 patient-years and was 98% complete, with a median of 9 patient-years (range, 0.013-17.4 years). Forty-six patients were at risk at 14 to 15 years, and 30 were at risk after 15 years. RESULTS: One hundred twenty-two (57%) of 212 patients died, 20 of them perioperatively. Fifteen-year actuarial Kaplan-Meier survival was 35.2% +/- 3.8%, and freedom from valve-related mortality was 84% +/- 3.5%, with no difference on the basis of position or age (<65 or >or=65 years). Percentages for freedom from thromboembolism, anticoagulant-related hemorrhage, endocarditis, and paravalvular leak were, respectively, 78.2% +/- 4%, 83.5% +/- 3.6%, 95.7% +/- 2%, and 97.3% +/- 1.4%, with no significant difference between the aortic and mitral positions. Freedom from structural valve deterioration was 71.8% +/- 5.6%: 88.9% +/- 6.2% in the aortic position versus 59.5% +/- 3.9% in the mitral position (P =.01) and 64.3% +/- 3% in the mitral-aortic position. In patients younger than 65 years, actual freedom from structural valve deterioration was less than that seen in older patients (84.5% +/- 3.5% vs 95% +/- 3.0%) and was better in the aortic versus the mitral position (92% +/- 4.5% vs 82% +/- 4.2%). CONCLUSION: The Hancock II porcine valve showed excellent 15-year durability. We recommend its use in patients 65 years of age, as well as in younger patients undergoing aortic replacement.

Hemodynamic and clinical outcomes with the Biocor valve in the aortic position: an 8-year experience.

OBJECTIVES: The aim of this study was to analyze the 8-year experience, survival, prosthetic complications, and hemodynamics of patients who received the Biocor valve, a new-generation tissue valve, in the aortic position. METHODS: From May 1992 through May 2001, 257 consecutive patients (129 women and 128 men; mean age, 75 +/- 6 years; age range, 45-91 years) received 258 aortic Biocor porcine prostheses. One female patient who received 2 Biocor valves in the aortic position during 2 consecutive operations was entered twice in the statistical analysis. Twelve (4.6%) patients had previous aortic valve operations. Preoperatively, 82 (32%) patients were in New York Heart Association functional class III or IV. Associated surgical procedures included coronary artery bypass grafting in 56 (21.7%) patients, aortic annular enlargement or aortoplasty in 20 (8%) patients, and others in 8 (3%) patients. Echocardiography was performed in the majority of long-term survivors (91.6%). Follow-up included 1215 patient-years and was 100% complete, with a median time of 5 patient-years (range, 0.4-10.5 years). RESULTS: There were 16 (6.2%) early deaths. According to a univariate analysis, New York Heart Association functional class III or IV, concomitant procedures, ejection fractions of less than 40%, and urgent operations were identified as significant perioperative risk factors. At follow-up, 75 patients died; 8-year actuarial Kaplan-Meier survival was 48% +/- 5%. At 8 years, the actuarial freedom from valve-related death was 92% +/- 2.6%, the freedom from thromboembolism was 93% +/- 2%, the freedom from anticoagulant-related hemorrhage was 95% +/- 2%, the freedom from endocarditis was 99% +/- 0.6%, the freedom from paravalvular leak was 96% +/- 1.5%, the freedom from all valve-related complications was 78% +/- 4.5%, and the freedom from structural valve deterioration was 95% +/- 3.7%. At 8 years, the actuarial freedom from structural valve deterioration was 89% +/- 10% and 95.8% +/- 4% in patients younger and older than 65 years, respectively. At 10 years, in patients older than 65 years, the actual freedom from structural valve deterioration was 97.9% +/- 2.1%, and the freedom from reoperation was 97% +/- 1.3%. New York Heart Association status was I or II in 90% of patients at the end of follow-up. The mean echocardiographic follow-up time was 4.6 +/- 2 years. By using Doppler echocardiography, the peak and mean transprosthetic gradients were determined to be 30.8 +/- 9.3 mm Hg and 16.6 +/- 5.3 mm Hg, respectively. Mean mass/volume ratio and left ventricular end-diastolic volume were 1.37 +/- 0.17 g/mL and 63.4 +/- 22.6 mL/m(2), respectively. The majority of patients showed a persistent left ventricular hypertrophy. CONCLUSION: The Biocor is an effective bioprosthesis with a low incidence of valve-related complications comparable with that of other second-generation bioprostheses. This stented porcine prosthesis provides satisfactory results in terms of hemodynamics, valve durability, and freedom from reoperation.

Hancock II bioprosthesis: a glance at the microscope in mid-long-term explants.

BACKGROUND AND OBJECTIVES: The Hancock II bioprosthesis is a second-generation porcine valve xenograft treated with the detergent sodium dodecyl sulphate (T6) to retard calcification. The aim of this investigation was to study the gross and microscopic features in Hancock II explants to assess the structural changes occurring with time. METHODS: Among 1382 Hancock II bioprostheses (701 isolated aortic, 421 isolated mitral, 130 double) implanted from 1983 to 1997 in 1252 patients, 22 (16 mitral, 6 aortic) were removed at reoperation until 1999 and were available for pathological investigation: infective endocarditis occurred in 5 and structural deterioration in 8, whereas in the remaining 9 xenografts reoperation was performed for nonstructural valve deterioration (paravalvular leak in 4 and prophylactic replacement in 5). Morphological investigation consisted of gross examination and x-ray, histologic, immunohistochemistry, electron microscopic, and atomic absorption spectroscopic examination. RESULTS: The cause of structural valve deterioration was dystrophic calcification in 4 cases (1 aortic, 3 mitral; range of time graft was in place, 101 to 144 months), non-calcium-related tears in 3 cases (all mitral, range 121 to 163 months), and commissural dehiscence in 1 (aortic, range 156 months). Five of the nonstructural valve deterioration explants (range 42 to 122 months) showed only pinpoint mineralization at the commissures. Mean calcium content in nonstructural deterioration explants was 14.70 +/- 22.33 versus 99.11 +/- 81.52 mg/g in explants with structural valve deterioration. Electron microscopic examination showed early nuclei of mineralization mostly consisting of calcospherulae upon cell debris. Local or diffuse lipid insudation was observed in all but 2 explants and consisted of cholesterol clefts, lipid droplets, and lipid-laden macrophages featuring foam cells. The lipid insudation was the most plausible cause of tearing in 2 explants. CONCLUSIONS: These pathologic findings support the clinical results of a delayed occurrence of structural failure of Hancock II bioprostheses and a mitigation of mineralization by the anti-calcification treatment. However, other factors such as lipid insudation may come into play in the long term.

Prosthesis size and long-term survival after aortic valve replacement.

OBJECTIVE: This study was undertaken to quantify the relationship between prosthesis size adjusted for patient size (prosthesis-patient size) and long-term survival after aortic valve replacement. METHODS: Data from nine representative sources on 13,258 aortic valve replacements provided 69,780 patient-years of follow-up (mean 5.3 +/- 4.7 years), with reliable survival estimates to 15 years. Prostheses included 5757 stented porcine xenografts, 3198 stented bovine pericardial xenografts, 3583 mechanical valves, and 720 allografts. Manufacturers' labeled prosthesis size was 19 mm or smaller in 1109 patients. Expressions of prosthesis-patient size assessed were indexed internal prosthesis orifice area (in centimeters squared per square meter of body surface area) and standardized internal prosthesis orifice size (Z, the number of SDs from mean normal native aortic valve size). Multivariable hazard domain analysis with balancing score and risk factor adjustment quantified the association of prosthesis-patient size with survival. RESULTS: Prosthesis-patient size down to at least 1.1 cm(2)/m(2) or -3 Z did not adversely affect intermediate- or long-term survival (P >.2). However, 30-day mortality increased 1% to 2% when indexed orifice area fell below 1.2 cm(2)/m(2) (P =.002) or standardized orifice size fell below -2.5 Z (P =.0003). The increased early risk affected fewer than 1% of patients receiving bioprostheses but about 25% of those receiving mechanical devices. CONCLUSIONS: Aortic prosthesis-patient size down to 1.1 cm(2)/m(2) or -3 Z did not reduce intermediate- or long-term survival after aortic valve replacement. However, patient-prosthesis size under 1.2 cm(2)/m(2) or -2.5 Z was associated with a 1% to 2% increase in 30-day mortality. Prosthesis-patient sizes this small or smaller were rarely implanted in patients receiving bioprostheses.

Biological or mechanical prostheses in tricuspid position? A meta-analysis of intra-institutional results.

BACKGROUND: Tricuspid valve replacement (TVR) is an uncommon procedure. The use of biological vs mechanical prostheses in TVR has pros and cons. Therefore, we debate the choice between the different types of valves by means of a meta-analysis of studies of the last decade. METHODS: The heading "tricuspid valve replacement and (bio* or mec*)" was used to retrieve studies from Medline, Current Contents, and Embase. Eight out of 11 studies met the preset strict criteria: intra-institutional comparison of results of biological or mechanical TVR. Survival of hospital-discharged patients was recalculated to reduce the effect of unbalanced perioperative risk factors on overall survival. Hazard ratio was obtained from actuarial survival graphics comparison and at-risk groups, according to the method described by Parmar. If missing, the number of patients at risk was approximated assuming constant and noninformative censoring. Hazard pooling was done according to study heterogeneity. Bioprostheses were assumed as the gold standard and mechanical prostheses assumed as the challenging device. Therefore, a hazard more than 1 pointed to a higher risk of mechanical prostheses. Our 1998 study was updated for this analysis. RESULTS: In this study, 1,160 prostheses and 6,046 follow-up years were analyzed. The pooled survival hazard ratio of mechanical prostheses versus bioprostheses was 1.07 (0.84 to 1.35, p = 0.60). The pooled freedom from reoperation hazard ratio was 1.24 (0.67 to 2.31, p = 0.67). Pooled survival differences were trivial, favoring mechanical prostheses at 1 (-0.04%) and 15 years (-1.1%) and favoring bioprostheses (+1.8%) at 10 years. CONCLUSIONS: There is not a gold standard in tricuspid prostheses replacement. Prosthetic choice is left to the surgeon's clinical judgment, taking into consideration each patient's characteristics and needs.

Case report: fibroelastoma of the papillary muscle of the mitral valve: diagnostic implications and review of the literature.

A 77-year-old woman was found accidentally to be in atrial fibrillation. Two-dimensional echocardiography revealed the presence of a mass attached to the anterior papillary muscle of the mitral valve. She was mildly symptomatic for dyspnea and asthenia. The patient was successfully operated on to excise the left ventricular mass and preserve the mitral valve apparatus. Morphological examination of the excised tissue led to a diagnosis of papillary fibroelastoma. Surgical treatment must be considered when such a tumor is diagnosed, even though asymptomatic, and especially if left-sided because of the high risk of systemic embolization.

Does the use of bilateral internal mammary artery (IMA) grafts provide incremental benefit relative to the use of a single IMA graft? A meta-analysis approach.

OBJECTIVES: Does the use of bilateral internal mammary artery (IMA) grafts provide incremental benefit relative to the use of a single IMA graft? METHODS: Meta-analysis by qualitative and quantitative protocol of the studies published in the literature in the last 15 years. Only eight, out of 149 observational studies found, met our criteria: surgical results of bilateral versus single IMA, patient age range from 20 to 89 years, exclusion of emergency and diabetic patients, study group larger than 100 patients, minimal follow-up time. The final sample size included 16362 patients. RESULTS: Late survival was evaluated at 5 and 10 years. The hazard ratio (HR) was calculated from seven studies, the difference of survival was from six and five studies, respectively. The effect size was summarized using a random effect model, suggested by the results of statistical test for homogeneity of the HR (P < 0.05) and of the survival difference at 5 (P < 0.05) and at 10 years (P < 0.05). The bilateral IMA estimate of combined HR was 0.79 (95% confidence limits, C.L. = 0.66/0.91). The combined difference of survival probability at 5 years was 0.014 (95% C.L. = -0.03/0.06) and at 10 years was 0.07 (95% C.L. = 0.003/0.170). CONCLUSION: There is significant evidence in favor of decreasing death risk of bilateral versus single IMA procedure.