Subcoronary Implantation Technique Research Articles

Long-term outcome of cryopreserved allograft for aortic valve replacement

ObjectiveThe most efficient surgical approach to severe aortic valve disease in the young adult is still debated: cryopreserved aortic allograft offers excellent hemodynamic and avoid anticoagulation, but long-term durability is influenced by structural valve deterioration (SVD). This study aimed to describe long-term results of aortic allografts and to identify factors influencing long-term durability. MethodsFrom January 1993 to August 2010, 210 patients underwent aortic allograft replacement via the free-hand subcoronary implantation technique (N = 55) or root replacement with coronary reimplantation (N = 155). Clinic and echocardiographic follow-up was updated to April 2016. ResultsOverall mortality and cardiac mortality occurred in 80 (38.1%) and 64 (30.5%) patients, respectively. Reoperation was required in 69 cases (32.8%), whereas SVD required reoperation in 57 cases (27.1%). No early endocarditis occurred, whereas late endocarditis occurred in 4 patients. The free-hand technique seems to be associated with improved left ventricular remodeling compared with the root-replacement technique, and smaller allograft size represents a predictor of reoperation independently on the surgical technique used. In the overall population, there were 44 women of childbearing age, and 37 patients remained pregnant during the follow-up of the study. No differences were found in the clinical outcomes among women who had children and who did not. ConclusionsCryopreserved allograft is a valid option, especially in complex infective endocarditis and in women of childbearing age. A careful choice of allograft size and implantation technique can reduce the risk of SVD.

Modified Ross-Konno procedure in children: subcoronary implantation technique with Konno incision for annular and subannular hypoplasia.

The technique of subcoronary autograft implantation for the Ross procedure has shown excellent durability of aortic valve function in adults. However, its use in children with hypoplastic aortic annulus or multilevel left ventricular outflow tract obstruction (LVOTO) was traditionally precluded. We combined this technique with a Konno incision and evaluated LVOTO relief and durability of the autograft function in growing patients. Between January 2012 and January 2017, 13 patients with severe LVOTO and hypoplastic aortic annulus underwent Ross-Konno procedure with subcoronary autograft implantation. The median age at operation was 14 months. Six were infants. Concomitant procedures included resection of endocardial fibroelastosis (n = 9), mitral valvuloplasty (n = 2) and aortic arch repair (n = 1). The Konno incision was enlarged with a patch. The autograft was implanted beneath the ostia of the coronary arteries, retaining external support by the native aortic annulus. A newborn with hypoplastic left heart complex and Turner syndrome died in hospital: early mortality of 7.7%. No residual LVOTO or autograft regurgitation was observed at discharge. At a median follow-up of 20 months, no death had occurred. No catheter or surgical reintervention on the aortic valve or any LVOT site was needed. All peak pressure gradients across the LVOT were <10 mmHg. No autograft regurgitation was detected. The Ross procedure using subcoronary implantation technique combined with LVOT Konno enlargement is feasible even in patients with multilevel LVOTO and marked size discrepancy between the autograft and native aortic annulus. Longer follow-up is indicated to confirm the expected durability of the autograft function.

The Freedom SOLO bovine pericardial stentless valve

The Freedom SOLO bovine pericardial stentless valve Olaf Stanger, Hendrik Tevaearai, Thierry Carrel Clinic for Cardiovascular Surgery, University Hospital Berne, Switzerland Abstract: The third-generation bovine pericardium Freedom SOLO (FS) stentless valve emerged in 2004 as a modified version of the Pericarbon Freedom stentless valve and as a very attractive alternative to stented bioprostheses. The design, choice of tissue, and anticalcification treatment fulfill most, if not all, requirements for an ideal valve substitute. The FS combines the single-suture, subcoronary implantation technique with the latest-generation bovine pericardial tissue and novel anticalcification treatment. The design allows imitation of the native healthy valve through unrestricted adaption to the patient&#39;s anatomy, reproducing a normal valve/root complex. However, despite hemodynamic performance superior to stented valves, we are approaching a critical observation period as superior durability, freedom from structural valve deterioration, and nonstructural failure has not been proven as expected. However, optimal performance and freedom from structural valve deterioration depend on correct sizing and perfect symmetric implantation, to ensure low leaflet stress. Any malpositioning can lead to tissue fatigue over time. Furthermore, the potential for better outcomes depends on optimal patient selection and observance of the limitations for the use of stentless valves, particularly for the FS. Clearly, stentless valve implantation techniques are less reproducible and standardized, and require surgeon-dependent experience and skill. Regardless of whether or not stentless valve durability surpasses third-generation stented bioprostheses, they will continue to play a role in the surgical repertoire. This review intends to help practitioners avoid pitfalls, observe limitations, and improve patient selection for optimal long-term outcome with the attractive FS stentless valve. Keywords: aortic valve, bioprosthesis, cardiac surgery, aortic valve replacement, tissue valve, stentless aortic valve, hemodynamics, long-term results

Ross procedure: is the root replacement technique superior to the sub-coronary implantation technique? Long-term results.

There is controversy over the use of the Ross procedure with regard to the sub-coronary and root replacement technique and its long-term durability. A systematic review of the literature may provide insight into the outcomes of these two surgical subvariants. A systematic review of reports between 1967 and February 2013 on sub-coronary and root replacement Ross procedures was undertaken. Twenty-four articles were included and divided into (i) sub-coronary technique and (ii) root replacement technique. The 10-year survival rate for a mixed-patient population in the sub-coronary procedure was 87.3% with a 95% confidence interval (CI) of 79.7-93.4 and 89.1% (95% CI, 85.3-92.1) in the root replacement technique category. For adults, it was 94 vs 95.3% (CI, 88.9-98.1) and in the paediatric series it was 90 vs 92.7% (CI, 86.9-96.0), respectively. Freedom from reoperation at 10 years was, in the mixed population, 83.3% (95% CI, 69.9-93.4) and 93.3% (95% CI, 89.4-95.9) for sub-coronary versus root replacement technique, respectively. In adults, it was 98 vs 91.2% (95% CI, 82.4-295.8), and in the paediatric series 93.3 vs 92.0% (95% CI, 86.1-96.5) for sub-coronary versus root replacement technique, respectively. The Ross procedure arguably has satisfactory results over 5 and 10 years for both adults and children. The results do not support the advantages of the sub-coronary technique over the root replacement technique. Root replacement was of benefit to patients undergoing reoperations on neoaorta and for long-term survival in mixed series.

Capturing echocardiographic allograft valve function over time after allograft aortic valve or root replacement

This study describes echocardiographic allograft valve function over time in a cohort of patients who were prospectively followed after allograft aortic valve or root replacement, illustrating the use of longitudinal data analysis for assessing valve function over time. Serial, standardized echocardiographic measurements of aortic regurgitation, aortic gradient, annulus diameter, left ventricular outflow tract diameter, and aortic diameter in 301 hospital survivors (mean age, 46 years; range, 16-83 years) after allograft aortic valve (N=77) or root (N=224) replacement were analyzed using nonlinear longitudinal models. Aortic regurgitation increased over time. At 15 years, 41% of patients had at least moderate aortic regurgitation. Younger patient age and subcoronary implantation technique were associated with increased aortic regurgitation. Aortic gradient increased over time (from 9.4 mm Hg at 6 months to 21.3 mm Hg at 15 years); both initial and increase in aortic gradient were greater in younger patients and after subcoronary implantation technique. Annulus diameter slightly increased (from 21.9 mm at 6 months to 22.4 mm at 15 years), whereas aortic diameter slightly decreased over time (from 34.3 mm at 6 months to 32.7 mm at 15 years). Left ventricular outflow tract diameter remained constant at 22 mm. Younger patients in the subcoronary implantation group had a larger annulus diameter. Both aortic regurgitation and stenosis increase over time after allograft aortic valve or root replacement. Younger patient age and use of the subcoronary implantation technique are associated with increased regurgitation and stenosis. The use of nonlinear longitudinal models allows for an insightful analysis of allograft valve function over time.

The Ross procedure: suitable for everyone?

In 1967, Donald Ross transferred the patient’s own pulmonary valve into the aortic root. Although results of this technique were encouraging, the Ross procedure did not gain widespread popularity until the late 1980s when surgeons started to implant the pulmonary autograft as a freestanding full root replacement with reimplantation of the coronary arteries. However, frequent dilatation of the pulmonary autograft was observed using the freestanding full root replacement technique. In contrast, the original subcoronary implantation technique and aortic root inclusion technique prevented dilatation in the long-term. Through advancing know-how in aortic root surgery and confidence, the Ross procedure has also been used in combined procedures and complex clinical presentations with good long-term results, which encourage continual use. However, the Ross procedure is a complex operation; careful patient selection and experience of the surgeon are mandatory requirements to achieve satisfactory results.

Surgical Repair of Atrio-Oesophageal Fistula Secondary to Transcatheter Ablation for Atrial Fibrillation: A Case Report and Literature Review

other prosthesis types. Over 6000 individual patients were included in the selected case series’. Mean patient age ranged from 64.0 to 76.0 years. 48.1% of patients were in New York Heart Association class 3–4 pre-operatively; the majority (75.7%) of cases used the subcoronary implantation technique. Operativemortality ranged from 1.8% to 9.6%, and five-year actuarial survival ranged from 71 3.0% to greater than 90.0%. Post-operative neurological event and prosthetic endocarditis rates ranged from 0% to 6.5% and 0.7% to 2.0% (respectively). Discussion: Despite a lack of randomised studies, in those identified the FSB performed comparably against alternative prosthesis options regarding inhospital mortality, long-term survival and reduction in left ventricular mass index. Included case series demonstrated robust post-operative outcomes in both the short and long-term also.With longer-term clinical and echocardiographic follow-up of the FSB, additional outcomes will assist in confirming its place in aortic valve and root surgery.

An alternative subcoronary implantation technique decreases the risk of complete heart block after stentless aortic valve replacement

Context:Stentless aortic valve prostheses have excellent hemodynamic profiles, but may be associated with an increased postoperative heart block when compared to conventional prostheses.Aims:To assess the effect of an alternative subcoronary implantation technique on postoperative complete heart block (CHB) and permanent pacemaker implantation (PPI) following aortic valve replacement (AVR) with stentless tissue valves.Settings and Design:A total of 130 consecutive patients undergoing AVR with stentless tissue valves by a single surgeon were studied retrospectively.Materials and Methods:A stentless tissue valve was implanted into 80 patients using the conventional modified subcoronary implantation technique, and 50 patients received a stentless tissue valve by an alternative subcoronary technique in which the inflow suture line is raised at the level of right-non coronary commissure. Data were collected at the time of hospital discharge and at 6–12 months postoperatively.Statistical Analysis Used:Independent samples t-test was used to compare continuous variables, and categorical variables were compared with the chi-square test.Results:Use of this new method reduced postoperative CHB (4.0% vs. 16.3%, P = 0.033), with fewer patients requiring PPI in the early postoperative period (6.0% vs. 18.8%, P = 0.041). Echocardiographic examination showed no differences in the effective orifice area, peak and mean aortic valve gradients, or left ventricular mass index between groups. Trivial or mild aortic regurgitation was found in 3.9% of patients with the conventional modified technique and 4.0% of patients undergoing the alternative technique, during follow-up (P > 0.05).Conclusions:Compared to the conventional subcoronary implantation technique, the alternative subcoronary implantation technique reduces the incidence of new CHB and the requirement of PPI following AVR with stentless tissue valves while preserving mid-term hemodynamic function.

Letter by Mokhles et al Regarding Article, “Prosthetic Heart Valve”

To the Editor: Drs Huang and Rahimtoola1 presented an interesting clinician update discussing several factors that have to be taken into consideration in choosing a prosthetic heart valve. However, the authors' considerations for prosthetic heart valve selection are, in our opinion, not complete, and deserve further discussion. With respect to the section on biological valves that need additional aortic root replacement, the Ross procedure and stentless xenograft valve implantation can also be performed successfully and durably by using the subcoronary implantation technique, which does not necessitate root replacement. These techniques can also provide patients with a hemodynamically superior valve substitute.2, …

Propensity analysis of survival after subcoronary or root replacement techniques for homograft aortic valve replacement

Homograft aortic valve replacement is associated with excellent clinical and hemodynamic outcomes. Valves are implanted predominantly by using 2 techniques: the freehand subcoronary technique or as an aortic root replacement. Our aim was to identify any difference in survival, durability, and clinical performance. Demographic, operative, and clinical data were obtained retrospectively through case-note review. All operations were performed by a single surgeon. Propensity score-adjusted analysis was used by developing a nonparsimonious logistic regression model for implantation with subcoronary versus root replacement. Actuarial survival and freedom from valve-related events were compared with Kaplan-Meier curves and multivariable proportional hazard Cox regression. Between January 1, 1991, and January 1, 2001, 215 patients underwent aortic valve replacement with a homograft. The subcoronary technique was used in 131 (61%) patients. Eighty-four (39%) patients underwent free-standing aortic root replacement. After propensity risk adjustment, the subcoronary implantation technique was associated with a decreased risk of 30-day death (adjusted odds ratio, 0.18; 95% confidence interval, 0.06-0.34; P = .03). Technique of insertion was not an independent predictor of overall mortality during follow-up after adjustment (propensity adjusted hazard ratio, 0.35; 95% confidence interval, 0.09-1.41; P = .18). There were no significant differences in 1- and 5-year actuarial survival, freedom from structural valve disease, endocarditis, or reoperation. Both the subcoronary and root replacement techniques for homograft aortic valve replacement are associated with excellent midterm survival and clinical performance. Root replacement was associated with an increased risk of perioperative death after adjustment for covariates by using propensity analysis.

Subcoronary Implantation of a Stentless Valve in Patients with Aortic Aneurysms

Experience with a new operation for patients with aortic valve disease and aneurysm or dissection of the ascending aorta is described. Twenty-four patients aged 66-87 years were operated on using a subcoronary implantation technique with a stentless aortic valve bioprosthesis and an extension using a vascular tube prosthesis. No major adverse cardiac events were observed in the postoperative period. This operation offers a safe alternative to the technically more demanding procedures of composite bioprosthetic ascending aortic replacement or full root replacement.

Ten-Year Experience With Stentless Aortic Valves: Full-Root Versus Subcoronary Implantation

We compared the midterm outcome after aortic valve replacement with the Freestyle stentless bioprosthesis for the full-root or subcoronary implantation technique, while adjusting for patient and disease characteristics by a propensity score. Between 1996 and 2005, 1,014 patients underwent aortic valve replacement with the stentless Medtronic Freestyle bioprosthesis, 168 using full-root technique. Based on a saturated propensity score, 148 matched pairs were created. Mean age of the 296 patients was 73 +/- 3 years. Mean follow-up time was 32 +/- 30 months (maximum, 116 months). Operative mortality was 4.7% and 2.7% (p = 0.36) in the full-root and subcoronary groups, respectively. Freedom from reoperation, prosthetic valve endocarditis, major bleeding, and thromboembolism after 9 years was 98% +/- 1% and 90% +/- 7% (p = 0.38), 95% +/- 3% and 92% +/- 7% (p = 0.76), 72% +/- 21% and 98% +/- 2% (p = 0.12), and 75% +/- 8% and 84% +/- 7% (p = 0.28), for full-root and subcoronary groups, respectively. Survival rates after 9 years were 34% +/- 24% and 33% +/- 11% (p = 0.46), for the full-root and subcoronary groups, respectively. Patients in the full-root group received larger valve sizes (p = 0.03), and the mean transprosthetic gradients at discharge were significantly lower for each valve size. Nevertheless, during follow-up, peak gradients decreased to a greater extent in patients presenting high peak gradients (>36 mm Hg) at discharge. As risk-adjusted comparison of both implantation techniques did not reveal any differences regarding operative and midterm outcomes, full-root replacement can be liberally performed in patients with small aortic roots, annuloaortic ectasia, or requiring replacement of ascending aorta.

Abstract 2069: Aortic Valve Replacement In Patients With Bicuspid Aortic Valve Disease Is Not Followed By Progressive Aortic Dilatation: A 15-year Study

Objectives A bicuspid aortic valve may be associated with an aortopathy, this may lead to progressive aortic dilatation over time. It is uncertain whether the ascending aorta should be replaced prophylactically during AVR in these patients. We analyzed change in ascending aortic diameter following AVR, to determine whether a clinically important aortic pathology exists in patients with bicuspid aortic valve disease. Methods Demographic, operative and clinical data were obtained retrospectively through casenote review. AVR was performed using a homograft or porcine stentless valve using the subcoronary implantation technique. Patients were grouped according to whether their native aortic valve was identified as tricuspid (TC) or bicuspid (BC) at operation. Serial transthoracic echocardiograms were analyzed to measure pre-operative and post-operative ascending aortic diameter. Results 217 patients underwent AVR between 1 st January 1991 and 1 st January 2001. Ninety patients had a bicuspid aortic valve, in the remaining 127 the valve was tricuspid. The bicuspid group was younger ( BC 62yr +/− 15, TC 71yr +/− 12 yrs; p &lt; 0.001). Follow-up echocardiography was performed 6.0 +/− 4.3 years post-operatively. Pre-operative ascending aortic diameter was similar (BC 3.2 +/− 0.5, TC 3.2 +/− 0.5 cm; p = 0.56) There was no difference in the increase in ascending aortic diameter over follow-up (BC 0.1 +/− 0.5, TC 0.0 +/− 0.5 cm; p = 0.34) Conclusion The clinical importance of “bicuspid aortopathy” in an older age group appears to be minimal. Additional aortic procedures designed to protect against progressive aortic aneurysmal disease in this setting are not justified.

Effect of surgeon on transprosthetic gradients after aortic valve replacement with Freestyle® stentless bioprosthesis and its consequences: A follow-up study in 587 patients

BackgroundThe implantation of stentless valves is technically demanding and the outcome may depend on the performance of surgeons. We studied systematically the role of surgeons and other possible determinants for mid-term survival, postoperative gradients and Quality of Life (QoL) after aortic valve replacement (AVR) with Freestyle® stentless bioprostheses.MethodsBetween 1996 and 2003, 587 patients (mean 75 years) underwent AVR with stentless Medtronic Freestyle® bioprostheses. Follow-up was 99% complete. Determinants of morbidity, mortality, survival time and QoL were evaluated by multiple, time-related, regression analysis. Risk models were built for all sections of the Nottingham Health Profile (NHP): energy, pain, emotional reaction, sleep, social isolation and physical mobilityResultsActuarial freedom from aortic valve re-operation, structural valve deterioration, non-structural valve dysfunction, prosthetic valve endocarditis and thromboembolic events at 6 years were 95.9 ± 2.1%, 100%, 98.7 ± 0.5%, 97.0 ± 1.5%, 79.6 ± 4.3%, respectively. The actuarial freedom from bleeding events at 6 years was 93.1 ± 1.9%. Estimated survival at 6 years was similar to the age-matched German population (61.4 ± 3.8 %). Predictors of survival time were: diabetes mellitus, atrial fibrillation, peripheral vascular disease, renal dysfunction, female gender > 80 years and patients < 165 cm with BMI < 24. Predictive models showed characteristic profiles and good discriminative powers (c-indexes > 0.7) for each of the 6 QoL sections. Early transvalvular gradients were identified as independent risk factors for impaired physical mobility (c-index 0.77, p < 0.002). A saturated propensity score identified besides patient related factors (e.g. preoperative gradients, ejection fraction, haematological factors) indexed geometric orifice area, subcoronary implantation technique and individual surgeons as predictors of high gradients.ConclusionIn addition to the valve size (in relation to body size), subcoronary technique (versus total root) and various patient-related factors the risk of elevated gradients after stentless valve implantation depends, considerably on the individual surgeon.Although there was no effect on survival time and most aspects of QoL, higher postoperative transvalvular gradients affect physical mobility after AVR.

Autograft Regurgitation and Aortic Root Dimensions After the Ross Procedure

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. 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. 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.

Late Disruption of a Freestyle Stentless Bioprosthesis Used for Repair of Sinus of Valsalva Aneurysm of Noncoronary Cusp

We present a case of disruption of the porcine aortic wall of the 27-mm Freestyle stentless bioprosthesis 5 years after the subcoronary implantation to exclude the sinus of Valsalva aneurysm of the noncoronary cusp. At the urgent reoperation, the inflow suture line was found to be intact, and therefore a new stented valve was sutured with the inflow Dacron cuff after removal of ruptured valve. The subcoronary implantation technique creates a cavity between the prosthetic and native aortic walls filled with hematoma. The outflow suture line dehiscence caused blood flow into the cavity, porcine aortic wall rupture, and leaflet destruction.

In-vitro study on the relationship between progressive sinotubular junction dilatation and aortic regurgitation for several stentless aortic valve substitutes

Stentless aortic valves are widely used due to their excellent hemodynamic properties. However, if the subcoronary implantation technique is used later dilatation of the sinotubular junction (STJ) can cause regurgitation. The aim of the study was to determine the dilatation tolerance of two commercially available stentless xenografts and fresh aortic and pulmonary roots against such dilatation. Four groups each comprising five specimens of fresh porcine aortic roots, pulmonary roots, Medtronic freestyle or Toronto SPV Xenografts were tested in a mock circulation using a special device for gradually increasing the diameter of the sinotubular junction. The smallest diameter D(r) where regurgitation occurs was measured and correlated with the starting diameter D(a) and expressed as per cent values. Opening and closing patterns were obtained by a high speed camera and flow characteristics were determined. The highest dilatation tolerance of STJ was found in the fresh porcine aortic roots (165%+/-10) followed by fresh pulmonary roots (146%+/-12), the Freestyle (143%+/-4) and the SPV (132%+/-5) bioprostheses. All differences were significant with P< or =0.05 except that between the fresh pulmonary roots and the two commercial available bioprostheses. Our results indicate that aortic homografts provide higher resistance against regurgitation induced by dilatation of the STJ than an autograft or the stentless xenografts, Freestyle xenograft followed by the Toronto SPV. The use of the full-root technique should be considered if aortic dilatation seems to be likely.

Use of stentless xenografts in the aortic position: determinants of early and late outcome

Background. Whether to perform a stentless aortic valve replacement (AVR) is not well established. Our aim was to determine the outcome after AVR with stentless xenograft valves. Methods. Between 1996 and 2001, a total of 404 patients (mean age 70.4 years) underwent a stentless AVR by one surgeon in our unit. Concomitant procedures were performed in 132 patients (33%). Twenty patients (6.4%) had undergone previous AVR. Eleven types of stentless xenograft valves were implanted: Medtronic Freestyle in 221 patients (55%), Shelhigh in 55 (14%), Shelhigh composite conduit in 33 (8%), Sorin in 26 (6%), Cryolife O‘Brien in 25 (6%), Aortech-Elan in 17 (4%), Edwards Prima in 14 (4%), Toronto SPV in 7 (2%), and other valves in 6 (1%). A subcoronary implantation technique was used in 302 cases (76%), complete root replacement in 62 (15%), and a modified Bentall-De Bono procedure in 33 (8%). Mean follow-up was 19.4 months (range, 1.2 to 60.6 months). Results. Overall hospital mortality was 4.2%. This was 2.4% for isolated AVR, 3.6% for AVR and coronary artery bypass grafting, 5.5% for replacement of two or more valves, and 12% for the modified Bentall procedure. On multiple logistic regression redo cardiac operation ( p = 0.0006), cardiogenic shock ( p = 0.001), left ventricular ejection fraction less than 0.30 ( p = 0.01), modified Bentall procedure ( p = 0.03), and endocarditis ( p = 0.04) were predictors of in-hospital death. Five-year freedom from thromboembolism, hemorrhage, prosthetic endocarditis, structural valve deterioration, and reoperation was 97%, 99%, 99%, 98%, and 96%, respectively. Kaplan-Meier survival at 5 years was 88%. On Cox regression, cardiogenic shock ( p = 0.001) and older age ( p = 0.03) were adverse predictors of survival. At echocardiographic examination within 6 months from the operation, mean aortic valve gradients were 15 ± 6 mm Hg, 12.8 ± 3 mm Hg, 10.8 ± 4 mm Hg, 9.3 ± 3 mm Hg, 9.1 ± 4 mm Hg, and 8.2 ± 3 mm Hg for valve sizes of 19, 21, 23, 25, 27, and 29 mm, respectively. Conclusions. The availability of several stentless valve designs facilitates the surgical treatment of diverse aortic valve or root diseases with encouraging early and midterm results. Patients requiring concomitant procedures may also benefit from the excellent hemodynamic characteristics of a stentless valve. We consider stentless AVR the treatment of choice for patients older than 60 years and those having small aortic roots.

Geometric mismatch between homograft (allograft) and native aortic root: a 14-year clinical experience.

We evaluated the effect of homograft/native aortic root geometric matching and mismatching on valve survival and myocardial remodeling. Between January 1, 1987 and March 2000, a total of 292 patients, aged 1.5-78 years (mean, 46.2 years), underwent freehand subcoronary aortic valve (AVR; n=207) and root (ARR; n=85) replacement with matched and mismatched cryopreserved homografts. All patients had pre- and postoperative two-dimensional Doppler echocardiographic studies. Two-hundred and forty-three survivors, excluding children with complete data on sizing, were followed at a total follow-up time of 1269 patient-years. Seventy percent received matched and 30% received mismatched aortic homografts. The homograft valve sizes ranged from 19 to 28 mm. Hospital death for elective first operation was 2.3%, and late death after a mean follow-up of 52 months was 7.9%. The patient survival at 14 years was 92+/-2%. By linear regression analysis, matched homografts were equal to or 1-2 mm less than the native aortic annulus (r(2)=0.73). The valve survival in patients with AVR and ARR was 72+/-4 and 80+/-8% at 14 years, respectively. The freedom from reoperation was 92+/-5, 77+/-4 and 48+/-10% at 14 years for matched, oversized and undersized homografts, respectively (P=0.001). The postoperative cardiac index of patients with 22 and 24 mm homografts was 3.8-4.1 l/m(2), and there was a regression of the left ventricular mass and end-diastolic diameter (P=0.001). The aortic homograft offers an excellent long-term clinical result. A mismatched homograft is a risk factor for postoperative aortic incompetence, reinfection with pseudoaneurysmal formation and reoperation for the freehand subcoronary implantation technique during the first 7 years of the postoperative period. It is prudent therefore to avoid mismatched homografts and use rather a properly sized stentless xenograft if a root replacement is not indicated.

Aortic valve replacement with the freestyle stentless bioprosthesis with respect to spacial orientation of patient coronary ostia

Objective: This study evaluates our results for safety and efficacy of aortic valve replacement using the Freestyle bioprosthesis (Medtronic, Inc, Minneapolis, Minn) with a new modified subcoronary implantation technique. This technique takes into account the spacial orientation of the stentless bioprosthesis in the aortic root with respect to the patient’s coronary ostia rather than the native commissures. Methods: Fifty-two consecutive patients with predominant aortic valve stenosis underwent aortic valve replacement with a Freestyle bioprosthesis by means of the described modified subcoronary technique over a 15-month period. Fifty of them were followed up by means of echocardiography at discharge, 6 months, and 1 year. There were 19 men and 31 women, with a mean age of 76 ± 7 years (range, 58-87 years). Valve size ranged from 21 to 27 mm. Results: Patients with bicuspid aortic valves had a significantly larger angle between both coronary ostia than patients with tricuspid aortic valves ( P = .0001). The peak and mean systolic gradients decreased significantly during the first postoperative year for each valve size ( P ≤ .001), and the effective valve areas increased significantly during this time interval for each valve size ( P ≤ .01). Only 13 patients had aortic insufficiency at discharge, which was trivial in 9 and mild in 4 patients. The prevalence of trivial aortic insufficiency decreased during the first postoperative year, and that of mild aortic insufficiency remained unchanged. The sinotubular junction diameter was significantly greater than that of the aortic anulus for each valve size before operation ( P < .001). The sinotubular junction diameter decreased significantly after aortic valve replacement and remained unchanged during the first postoperative year for each valve size ( P < .001). Conclusions: Aortic valve replacement with the Freestyle bioprosthesis using the modified subcoronary technique, which takes into account the spacial orientation of the patient’s coronary ostia, has hemodynamic results similar to those of other series with different subcoronary implantation techniques. This technique is reproducible, safe at the coronary ostial level, and effective in accommodating variability in angles between human coronary ostia, ranging from 130° to 170°. Moreover, the great preoperative discrepancies between aortic anulus and sinotubular junction diameters are corrected immediately after operation. (J Thorac Cardiovasc Surg 2000;119:1185-93)