Thrombocytopenia after implantation of the Perceval S aortic bioprosthesis.

OBJECTIVE: The Perceval S bioprosthesis (LivaNova PLC, London, United Kingdom) is based on the Freedom Solo aortic bioprosthesis (LivaNova PLC), which has been reported to be associated with perioperative thrombocytopenia. We compared platelet counts after aortic valve replacement with the Perceval S with those with other aortic valve bioprostheses. METHODS: A total of 87 patients receiving aortic valve replacement were included in this retrospective study; 25 patients received the Perceval S, 23 patients received the Labcor TLPB-A (Labcor, Belo Horizonte, Brazil), and 39 patients received the Hancock II bioprosthesis (Medtronic, Minneapolis, Minn). Thrombocyte count was corrected for hematocrit. Multivariable analyses were performed to assess the potential effect of other variables. RESULTS: Preoperatively, there were no differences in platelet counts comparing the Perceval S group (median 200/nl, interquartile range, 157-252) and the control group (Labcor: median 213/nl, interquartile range, 160-246, Hancock: median 227/nl, interquartile range, 183-280, P = .23). Postoperatively, there was significant evidence that the minimum platelet count (median, Perceval: 47, interquartile range, 38-66; Labcor: 76, interquartile range, 61-110; Hancock: 78, interquartile range, 61-111/nl; P = .001), both absolute and corrected, was lower for the Perceval S, even after allowing for other variables. The significant difference in absolute platelet counts persisted until discharge or death. However, there were no significant differences regarding blood loss, transfusion requirements, or rates of reoperation for bleeding. CONCLUSIONS: After aortic valve replacement, platelet counts in patients with the Perceval S decrease more severely compared with other bioprostheses, but in our small study we found no evidence of a detrimental clinical effect of this phenomenon. Future studies have to confirm our findings and investigate a cause for this phenomenon.

Leukocyte depletion during cardiopulmonary bypass in routine adult cardiac surgery.

OBJECTIVES: Cardiopulmonary bypass (CPB) elicits an inflammatory response which is potentially harmful and that is partly caused by activation of leukocytes. Despite promise from earlier studies, however, the value of intraoperative leukocyte-depletion (LD) remains equivocal. We studied the effect of LD during routine cardiac surgery. METHODS: For a short period (2.5 months), all operations at our institution were performed with leukocyte filters (Pall, East Hills, NY, USA) in the arterial and cardioplegia lines of the CPB. Those patients operated immediately before and after this period served as controls. RESULTS: In each group, 266 predominantly male (70%) patients were studied. A broad spectrum of operations including emergency surgery was evaluated, which was comparable between the groups (P=0.41). There were no significant differences regarding the preoperative data, but the preoperative leukocyte count tended to be lower in the leukodepletion-group (7961±2415 vs. 8444±2951, P=0.050). Despite this, no difference between the groups regarding the postoperative leukocyte count was observed. Significantly more LD-patients were extubated within 12 h postoperatively (69% vs. 60% in the control-group, P=0.029), but there were no significant differences regarding 30-day mortality (0.4% vs. 1.1%, P=0.37), transfusion requirements or major morbidity. CONCLUSIONS: In a retrospective study on adding LD filters to all cardiac operations with CPB in adults, we did not observe a clear benefit of intraoperative LD with the strategy used (continuous filtration plus filtration of cardioplegia).

Major adverse cardiac and cerebrovascular events after the Ross procedure: a report from the German-Dutch Ross Registry.

BACKGROUND: The purpose of the study is to report major cardiac and cerebrovascular events after the Ross procedure in the large adult and pediatric population of the German-Dutch Ross registry. These data could provide an additional basis for discussions among physicians and a source of information for patients. METHODS AND RESULTS: One thousand six hundred twenty patients (1420 adults; 1211 male; mean age, 39.2±16.2 years) underwent a Ross procedure between 1988 and 2008. Follow-up was performed on an annual basis (median, 6.2 years; 10 747 patient-years). Early and late mortality were 1.2% (n=19) and 3.6% (n=58; 0.54%/patient-year), respectively. Ninety-three patients underwent 99 reinterventions on the autograft (0.92%/patient-year); 78 reinterventions in 63 patients on the pulmonary conduit were performed (0.73%/patient-year). Freedom from autograft or pulmonary conduit reoperation was 98.2%, 95.1%, and 89% at 1, 5, and 10 years, respectively. Preoperative aortic regurgitation and the root replacement technique without surgical autograft reinforcement were associated with a greater hazard for autograft reoperation. Major internal or external bleeding occurred in 17 (0.15%/patient-year), and a total of 38 patients had composite end point of thrombosis, embolism, or bleeding (0.35%/patient-year). Late endocarditis with medical (n=16) or surgical treatment (n=29) was observed in 38 patients (0.38%/patient-year). Freedom from any valve-related event was 94.9% at 1 year, 90.7% at 5 years, and 82.5% at 10 years. CONCLUSIONS: Although longer follow-up of patients who undergo Ross operation is needed, the present series confirms that the autograft procedure is a valid option to treat aortic valve disease in selected patients. The nonreinforced full root technique and preoperative aortic regurgitation are predictors for autograft failure and warrant further consideration. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00708409.

Anti-HLA antibodies and pulmonary valve allograft function after the Ross procedure.

BACKGROUND AND AIM OF THE STUDY: Rejection is a plausible cause of failure of allograft valves, but has not been demonstrated unequivocally in humans. A cross-sectional study has been conducted on the frequency of anti-human leukocyte antigen (HLA) antibodies in order to identify any correlation with allograft function in adult patients, following the Ross procedure. METHODS: Anti-HLA antibodies were determined during regular follow up (median 1.1 years postoperatively) in a random sample of 197 patients (151 males, 46 females; mean age 46 +/- 13 years). Panel-reactive antibodies (PRA) were determined by cytotoxicity testing; anti-HLA class 2 antibodies (HLA2AB) were determined by ELISA in a subgroup of 94 patients. Echocardiographic examinations were performed during the first visit and at a median of 6.8 years postoperatively. RESULTS: The prevalence of positive antibody tests was 47% for PRA and 52% for HLA2AB. A slight deterioration of allograft valve function occurred between the two examinations (median maximal pressure gradient increased from 9 mmHg to 13 mmHg, p < 0.001; median degree of regurgitation increased from zero to trivial, p = 0.020). The degree of regurgitation was slightly, but significantly, higher in PRA-positive patients at both examinations (p = 0.008 and p = 0.038). No relationship was observed between PRA status and pressure gradients, nor between HLA2AB status and allograft valve function. Neither were any other risk factors for allograft valve deterioration identified. CONCLUSION: Subtle, clinically irrelevant and temporally stable differences with regard to regurgitation across the allograft were observed between PRA-positive and -negative patients. These findings neither proved nor disproved rejection, but rather suggested that a slow deterioration of allograft valve function was complex, and most likely multifactorial.

Fifty-two months' mean follow up of decellularized SynerGraft-treated pulmonary valve allografts.

BACKGROUND AND AIM OF THE STUDY: It has been reported previously that the use of a decellularized pulmonary allograft (SynerGraft; CryoLife Inc.) for right ventricular outflow tract reconstruction in adults is associated with reduced immunization. The implantation appeared to be safe, but was not associated with any detectable clinical or echocardiographic advantage. The study aim was to follow further the outcome of SynerGraft patients. METHODS: Twenty-three adult patients (19 males, four females) each received a SynerGraft-allograft during a Ross procedure. A further 49 patients (37 males, 12 females) who underwent a Ross procedure using a conventional pulmonary allograft during the same period served as controls. Follow up examinations using transthoracic echocardiography in standard views was performed on a regular basis. The latest follow up was performed after a mean of 52 months. RESULTS: Directly after implantation, there were no echocardiographic differences between the two groups, but with time the pressure gradients increased significantly (p <0.001) in both groups. At the latest follow up, pressure gradients were slightly higher across the SynerGraft-allograft valves than across conventional allografts (Pmax 18.2 +/- 9.0 versus 14.0 +/- 6.9 mmHg, respectively; p = 0.049). On regression analysis (considering pre- and intraoperative variables), 'SynerGraft-allograft' was the only variable predicting the increase in pressure gradient from its postoperative value to that at follow up. However, no clinical differences were observed between the groups. CONCLUSION: The present results relate to the longest follow up on decellularized pulmonary SynerGraft-allografts conducted to date. No reoperations were required after a mean follow up of 52 months, and the echocardiographic results were stable after the first postoperative year. Based on these data, the use of pulmonary SynerGraft-allograft valves in adults appears not to provide any advantage over conventional allografts, although further follow up is warranted before any final judgment is made regarding this new technology.

Cardiac surgery in patients on dialysis: decreased 30-day mortality, unchanged overall survival.

BACKGROUND: The risk of cardiac surgery in dialysis-dependent patients is high, but little is known about the determinants of survival. We initiated a retrospective multicenter study to overcome this limitation. METHODS: Nine centers provided data on 522 patients (70% male, aged 61 +/- 11 years) who had chronic dialysis-dependent renal failure. A 14-year period was covered. Most patients had coronary artery bypass grafting, either with (n = 103) or without (n = 326) valve surgery. Multivariable analysis of survival was explored using Cox models. RESULTS: The proportion of patients with diabetes mellitus increased significantly (from 17%, 1989 to 1993, to 32%, 2000 to 2003; p = 0.021) and was independently associated with 30-day mortality (odds ratio = 3.30, p = 0.001) The mean 30-day mortality was 12% (n = 60), but declined significantly during the study period (from 28%, 1989 to 1993, to 7%, 2000 to 2003; p = 0.003). The 5-year survival probability was 42% (95% confidence interval: 36% to 47%). Patients who had renal transplantation during follow-up (n = 17) had the best survival probability (hazard ratio [HR] = 0.14, p = 0.007). Sinus rhythm (HR = 0.48, p < 0.001) and use of internal thoracic artery grafts (HR = 0.67, p = 0.006) proved beneficial for long-term survival. Predictors of death during long-term follow-up were emergency surgery (HR = 2.25, p = 0.001), diabetes mellitus (HR = 1.46, p = 0.020), number of allogenic transfusions (HR = 1.03/unit, p = 0.015), and age (HR = 1.04/year, p < 0.001). CONCLUSIONS: In dialysis-dependent patients, cardiac surgery has become significantly safer in recent years, but the overall prognosis of the patients remains poor. The observed improvements in the perioperative survival do not necessarily translate into an improved long-term prognosis. Diabetes mellitus is an important independent risk factor for perioperative mortality and death during follow-up.

Autograft regurgitation and aortic root dimensions after the Ross procedure: the German Ross Registry experience.

BACKGROUND: Autograft regurgitation and root dilatation after the Ross procedure is of major concern. We reviewed data from the German Ross Registry to document the development of autograft regurgitation and root dilatation with time and also to compare 2 different techniques of autograft implantation. METHODS AND RESULTS: Between 1990 and 2006 1014 patients (786 men, 228 women; mean age 41.2+/-15.3 years) underwent the Ross procedure using 2 different implantation techniques (subcoronary, n=521; root replacement, n=493). Clinical and serial echocardiographic follow up was performed preoperatively and thereafter annually (mean follow up 4.41+/-3.11 years, median 3.93 years, range 0 to 16.04 years; 5012 patient-years). For statistical analysis of serial echocardiograms, a hierarchical multilevel modeling technique was applied. Eight early and 28 late deaths were observed. Pulmonary autograft reoperations were required in 35 patients. Initial autograft regurgitation grade was 0.49 (root replacement 0.73, subcoronary 0.38) with an annual increase of grade 0.034 (root replacement 0.0259, subcoronary 0.0231). Annulus and sinus dimensions did not exhibit an essential increase over time in both techniques, whereas sinotubular junction diameter increased essentially by 0.5 mm per year in patients with root replacement. Patients with the subcoronary implantation technique showed nearly unchanged dimensions. Bicuspid aortic valve morphology did not have any consistent impact on root dimensions with time irrespective of the performed surgical technique. CONCLUSIONS: The present Ross series from the German Ross Registry showed favorable clinical and hemodynamic results. Development of autograft regurgitation for both techniques was small and the annual progression thereof is currently not substantial. Use of the subcoronary technique and aortic root interventions with stabilizing measures in root replacement patients seem to prevent autograft regurgitation and dilatation of the aortic root within the timeframe studied.

Remodeling or reimplantation for valve-sparing aortic root surgery?

BACKGROUND: Valve-sparing operations are gaining increasing acceptance; however, there is an ongoing discussion about the technique-specific indications. We present our experience with a follow-up of 123 months. METHODS: Between July 1993 and July 2005, 164 consecutive patients were operated on using the remodeling (group A, n = 96) or reimplantation technique (group B, n = 68). Fifty-seven patients presented with acute type A dissection. Aortic regurgitation was present in 84%. Follow-up was 54.7 +/- 28 in group A and 48.4 +/- 37.3 months in group B. RESULTS: After urgent operations, 4 patients died in each group, but none died after elective surgery. Late mortality was 8% in group A and 4% in group B. Seven patients of group A and 1 in group B required reoperation. Echocardiographic follow-up of reoperation-free survivors showed that 3 patients (all group A, 1.3%) had aortic regurgitation of more than grade II. Root diameter, valve pressure gradient, and valve orifice area were comparable. No gross thromboembolic or bleeding events occurred. CONCLUSIONS: Aortic valve-sparing operations can provide acceptable long-term results in both techniques. Particular care to the annulus in the remodeling technique and different prosthesis designs in the reimplantation technique may overcome the intrinsic problems of each procedure.

[Reconstructive surgery of the aortic valve: the Ross, David, and Yacoub procedures]. / Rekonstruktive Aortenklappenchirurgie: Ross-, David- und Yacoub-Verfahren.

The aortic valve consists of three cusps attached to the wall of the aortic root. During the cardiac cycle, the aortic root undergoes complex movements that precede and aid opening and closing of the aortic valve. The aortic valve cusps themselves form thin-walled pocket-like structures, made from specialized tissue with fibrous, elastic, nervous, and muscular properties. The complex interactions of this tissue with the aortic root and within the cardiac cycle are only incompletely understood yet. In summary, the aortic valve is a complex structure which shows a perfect function in systole and diastole and under a wide range of hemodynamic conditions. No valve prosthesis (so far) can keep up with the function of the native aortic valve. Therefore, surgical techniques have been invented that aim at sparing the aortic valve or replacing it with very similar autologous tissue. Besides the resulting (near) normal valve function, one appealing advantage of these techniques is that oral anticoagulation can be abandoned completely. If the valve cusps themselves are normal, but the aortic root is aneurysmatic or dissected (with or without resulting secondary aortic insufficiency), the aortic valve can be spared by resecting the aortic root tissue and replacing it by a vascular graft. The aortic valve can then be implanted into the vascular graft in a way described by David, or can be remodeled into it (Yacoub technique) - in this case, the graft first needs to be incised at its base so that the three commissures of the valve can be sewn into the three incisions. This way pseudosinuses within the vascular graft are created. The sinuses within the aortic root are considered important for aortic valve function and coronary perfusion. On the other hand, incisions at the base of the vascular graft harbor the potential for redilatation of the aortic root because of a missing circular fixation. Such a fixation is achieved by the David technique. Therefore, there is a great debate in the surgical community which valve-sparing technique is the best and numerous modifications of the original techniques exist. A clear clinical advantage of one technique over the other could not be demonstrated so far, but many authorities advise that the David technique is to be used preferentially in patients with Marfan's syndrome (or other connective tissue disorders) and those with a very wide basal aortic root. If the aortic valve cusps themselves are diseased and cannot be reconstructed, the autologous pulmonary valve is the most physiological substitute. Replacing the aortic valve with the autologous pulmonary valve is named Ross procedure. The defect in the right ventricular outflow tract that is created while harvesting the autograft must be reconstructed during the same procedure; usually, a pulmonary valve allograft is used for this purpose. With all reconstructive surgical techniques and with all autologous replacements there is a risk of reoperation, mainly (besides technical issues) because it is feared that leaving autologous tissue in place leads to recurrence of the original illness. The published results, however, with aortic valve-sparing surgery and with the Ross procedure show that the risk of reoperation appears to be very acceptable. This statement is especially true for the Ross procedure for which more and longer experience exists worldwide. Echocardiographic studies show that the aortic valve function after valve-sparing techniques and - especially - after the Ross procedure is indeed excellent. Therefore, patients with aortic root pathologies or aortic valve diseases should be informed about valve-sparing aortic root reconstructive techniques or the Ross procedure. The choice of technique should be made in close contact between patient, cardiologist, and cardiac surgeon. However, the described techniques require extensive experience within the surgical team.

The Na+/H+ exchange inhibitor cariporide is washed out of the myocardium by crystalloid cardioplegia.

BACKGROUND: Inhibition of the Na (+)/H (+) exchanger (NHE) is cardioprotective, but dosage and timing of NHE-inhibitors are critical for their efficacy. We studied the effect of a new dosing regime of the NHE-inhibitor cariporide on myocardial function and damage after cardioplegic arrest (CPA) and determined its myocardial and serum concentrations. METHODS: 3 pigs received a bolus of 180 mg cariporide intravenously (i. v.) and were sacrificed shortly thereafter to allow measurement of the myocardial concentrations of cariporide. Subsequently, 10 pigs were randomized to receive either i. v. cariporide (bolus followed by an infusion of 40 mg/h) or placebo. Cardiopulmonary bypass was initiated, and the heart was arrested for 60 minutes by infusion of St. Thomas Hospital solution. Left ventricular (LV) function was studied using microsonometry. Myocardial damage was assessed by troponin T. Serum concentrations of cariporide were measured throughout the study, and myocardial concentrations were measured before the end of CPA and 180 minutes thereafter. RESULTS: Cariporide was present in all myocardial specimens (median: 1.4 ng/mg) studied previously. In the main study, LV function or myocardial damage did not differ significantly between the groups at any time point. Stable serum cariporide concentrations were achieved (3.4 +/- 0.5 microg/ml). Cariporide was detectable in only one of the myocardial biopsies obtained before the end of CPA, but 180 minutes thereafter, the myocardial cariporide concentration was 2.5 +/- 0.3 ng/mg. CONCLUSION: We observed no effect of i. v. cariporide on LV function or myocardial damage after cardioplegic arrest. Our data suggest that cariporide is washed out of the myocardium by repeated application of crystalloid cardioplegia. Thus, the mode of delivery also appears to be critical for cardioprotection with NHE-inhibitors.

Optimal size of a monocusp patch for reconstruction of a hypoplastic pulmonary root: an experimental study in pigs.

BACKGROUND: Transannular patching is often performed to relieve congenital pulmonary stenosis, especially in tetralogy of Fallot. Theoretically, a monocusp patch can reduce patch-related pulmonary regurgitation, but the optimal size relation between the implant and the native hypoplastic pulmonary root is not well defined. METHODS: In 11 pigs, peak pressure gradient and regurgitation fraction across the pulmonary root were measured. During cardiopulmonary bypass, two cusps including the pulmonary artery wall were resected and the midpoint of the free margin of the remaining cusp was sutured to the sinus wall to imitate a hypoplastic pulmonary root. Transannular patching was performed using a noncoronary segment of a porcine aortic root. After discontinuation of cardiopulmonary bypass, all measurements were repeated. Thereafter, the cusp of the patch was resected, and all measurements again repeated. Anatomic dimensions were determined after the pigs had been sacrificed. RESULTS: Regurgitation fraction increased from 0.2% +/- 3.4% at baseline to 15.5% +/- 6.2% after reconstruction with a monocusp patch and to 60.0 +/- 18.6% after the cusp of the monocusp patch had been resected (p < 0.001). The median peak pressure gradient increased from 0 to 1 to 6 mm Hg (p = 0.013), respectively. The regurgitation fraction negatively correlated with the ratio of the length of the monocusp patch to that of the hypoplastic pulmonary root (r = -0.63, p = 0.037). CONCLUSIONS: A monocusp patch for reconstruction of a hypoplastic pulmonary root results in significantly less regurgitation than a nonvalved patch of the same size, while the peak pressure gradient remains normal. The lowest regurgitation fraction was observed with a monocusp patch two-times the length of the circumference of the hypoplastic pulmonary root.

[Aortic valve operation in young adults]. / Aortenklappenoperationen bei jungen Erwachsenen.

Young adults who have to undergo aortic valve surgery will frequently have (relative) contraindications to oral anticoagulation therapy because either pregnancy is planned or their life-style is very active. This review focuses on the surgical options available and assesses the literature focusing on the experience with each option obtained in young adults. There are no randomized studies in this age group which compare mechanical aortic valve replacement with any alternative option with regard to survival, need for reoperation, or quality of life. Among the alternative techniques, the Ross-procedure (pulmonary autograft) and aortic valve repair are of special interest. With the Ross-procedure, there is a rather large experience in young adults, and the results up to 10 years postoperatively are excellent. Unfortunately, there is only limited experience with this technique beyond that time.

Mid-term findings on echocardiography and computed tomography after RVOT-reconstruction: comparison of decellularized (SynerGraft) and conventional allografts.

OBJECTIVE: The immune response against human-leucocyte-antigens on donor-cells may be an important factor contributing to the degeneration of allograft-valves. We have previously reported that the use of the decellularized allograft SynerGraft (CryoLife) reduces the immunologic response of the allograft-recipient. In this study we compare the echocardiographic and computed tomography angiographic (CTA) findings of SynerGrafts with conventional cryopreserved allografts. METHODS: 22 patients who received a pulmonary SynerGraft (SG-group) (21 during a Ross-procedure) underwent CTA and resting echocardiography (median: 10 months postoperatively). 47 randomly chosen patients who underwent a Ross-procedure served as controls (C-group) (median: 32 months postoperatively). RESULTS: Neither the pressure gradients (mean: SG=9+/-4 vs C=10+/-4mmHg; P=0.64) across the allograft, nor the effective orifice area (EOAI) (SG=0.93+/-0.80 vs C=0.93+/-0.42cm(2)/m(2); P=0.96) differed between the groups. The EOAI showed a significant correlation with the smallest allograft-conduit-area measured on CTA (r=0.81; P<0.001) which was most frequently (n=34) found in the proximal postvalvular tubular part of the conduit. Calcifications (n=11) or a fibroproliferative reaction (n=15) were rarely observed. Overall, there were no radiologic differences between the groups. On CTA, the smallest diameter of the allograft-conduits was significantly smaller than the diameter given on the cryopreservation protocol (SG=16+/-3 and C=17+/-3mm vs 25mm in both groups; P<0.001 each) whereas the diameter of the distal part of the allograft was not (SG=24+/-2, P=0.066, and C=25+/-3mm, P=0.82). CONCLUSIONS: Despite a significant shorter follow-up in the SynerGraft-group, no functional or radiologic differences were observed as compared to control-patients. The smallest diameter is located almost exclusively at the proximal level of allograft-conduits.

The extent of akinesis is predictive of the in-hospital mortality from endoaneurysmorrhaphy.

Endoaneurysmorrhaphy (EAR) has become an important therapeutic option in the treatment of patients with left ventricular (LV) aneurysm and congestive heart failure. Today, more and more patients are referred for EAR with a dilated akinetic LV rather than a classic dyskinetic LV aneurysm. Little is known about the contribution of the extent of akinesis to perioperative mortality. We reviewed the data of 147 patients with anterior left ventricular aneurysms undergoing EAR. Seventy percent of the patients were male; mean age was 62+/-9 years. Demographic, hemodynamic, angiographic and surgical variables were analyzed using univariate statistic tests in order to determine risk factors for in-hospital mortality.Eighty-two percent of the LV aneurysms had at least some dyskinesia, but 70% were mainly akinetic. 133 patients had additional bypass surgery, one had additional mitral valve replacement. In-hospital mortality was 4.1% (n=6). Risk factors for in-hospital mortality were the total extent of akinetic myocardium (p=0.027) in the 30 degrees RAO view and the duration of cardiopulmonary bypass (CPB, p=0.0068) which was itself dependent on the LV ejection fraction (p=0.001), the number of stenosed coronary arteries (p=0.004), and the extent of akinesis (p=0.023). The extent of dyskinesia was not associated with either perioperative mortality (p=0.36) or CPB duration. EAR can be performed with acceptable perioperative results. Because akinesis increases in many patients with time, and because the duration of ECC was dependent on variables reflecting the severity of the underlying heart disease, our findings underscore the importance of optimal timing for the surgical intervention.