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Division of Thoracic and Cardiovascular Surgery, University of Florida, College of Medicine, Gainesville, Florida
Accepted for publication January 7, 2009.
* Address correspondence to Dr Hess, Jr, Division of Thoracic and Cardiovascular Surgery, University of Florida, PO Box 100286, Gainesville, FL 32610 (Email: hesspj{at}surgery.ufl.edu).
Presented at the Fifty-fifth Annual Meeting of the Southern Thoracic Surgical Association, Austin, TX, Nov 5–8, 2008.
| Drs Martin and Hess disclose that they have received a speaker's honoraria from Terumo Cardiovascular Systems. No author has stock ownership or a financial conflict of interest.
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Abstract |
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Methods: The study included all patients undergoing the Florida sleeve procedure who had at least 2 years of postoperative echocardiographic follow-up. Data were acquired preoperatively and postoperatively at 1 week and 1, 2, and 3 years. Measurements analyzed included left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), and degree of aortic insufficiency.
Results: Complete echocardiographic data for a mean 32 ± 6.3 months after repair were available for 18 patients. Mean LVEDD decreased from 51.6 ± 7.4 to 49.7 ± 6.3 mm at 1 week (p = 0.05) and 47.1 ± 6.3 mm at 1 year (p = 0.008), and remained unchanged at 47.2 ± 6.6 and 47.1 ± 5.0 mm at 2 and 3 years. Mean LVESD decreased from 35.2 ± 7.6 to 32.9 ± 7.0 mm at 1 week (p = 0.002) and 30.7 ± 5.6 mm at 1 year (p < 0.001), and remained unchanged at 30.9 ± 6.2 and 31.7 ± 4.9 mm after 2 and 3 years. The mean grade of aortic insufficiency decreased from 2.61 ± 0.78 to 1.39 ± 0.85 mm at 1 week (p < 0.001) and remained 1.39 ± 0.84 mm at 1 year. Aortic insufficiency increased to 1.72 ± 0.89 (p = 0.03) at 2 years and decreased to 1.67 ± 0.50 (p = 0.59, from 1 week postoperatively) at 3 years.
Conclusions: The sustained reduction of left ventricular dimensions 3 years after operation suggests the Florida sleeve procedure is a durable valve repair. A minor increase in the degree of aortic insufficiency warrants close follow-up, but the absence of an increase of LVEDD supports continued use of the procedure in closely studied series.
Aortic insufficiency (AI) associated with root aneurysms is usually caused by simple lateral displacement of the leaflets. When root dilatation pulls otherwise normal leaflets from the luminal midpoint, central jet AI ensues and the functional classification is type I. The diagnostic accuracy of echocardiography for type I regurgitant lesions exceeds 90%, and repairability of the functional type I regurgitant valve associated with root aneurysms approaches 100% [1]. The excellent midterm to long-term durability of repairs of the type I valve leak during root aneurysm resection is well documented [1–5].
The measurements for assessment of long-term durability after repair of incompetent aortic valves are similar to the preoperative evaluation, and ideally include echocardiographic determination of left ventricular dimensions as well as systolic function and degree of AI [6, 7]. Modern valve-sparing procedures for AI associated with root enlargement require resection of the dilated sinuses, followed by remodeling of the aortic root or reimplantation of the aortic valve inside a Dacron (Dupont, Wilmington, DE) tube graft. Cautionary reports of progressive sinus enlargement in some patients after root remodeling procedures have encouraged more interest in valve reimplantation techniques where circumferential support of the root is assured [8, 9].
We previously described a simplified reimplantation technique in which the sinuses are not resected and the coronary artery origins are left intact [10]. Stability of the annulus, sinuses, and sinotubular junction is accomplished using a periaortic Dacron tube conduit as a sleeve. Reasonable concerns about this external tube or sleeve repair include long-term durability of the valve and dimensional stability of the reinforced root. To assess these concerns, we retrospectively reviewed preoperative and postoperative echocardiographic measurements customarily used to monitor AI; specifically, left ventricular and aortic dimensions, grade of AI, and left ventricular ejection fraction (LVEF).
The purpose of the study was to evaluate the durability of the aortic valve and dimensional stability of the root after the Florida sleeve repair for functional type I AI associated with aortic root aneurysms.
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Patients and Methods |
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TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
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Valves with normal or mildly attenuated leaflets were accepted for the sleeve procedure, but valves with prolapsed, fenestrated, or otherwise damaged leaflets underwent valve replacement and were not included in the study. Some reports of successful valve repair during root aneurysm resections have included valves with leaflet prolapse or fenestration (type 2 lesion) [11, 12], but during this developmental stage of the sleeve procedure, valves with type 2 leaflet pathology were specifically excluded. All incompetent valves repaired in this series were functional type 1; that is, aortic insufficiency due to enlargement of the aortic root with normal leaflets [1, 13].
Mathematic models to predict the ideal diameter of the annuloplasty have been exhaustively pursued by others [14], but with the sleeve procedure, the final annular diameter is determined almost exclusively by the point of reduction at which good leaflet coaptation occurs [10]. This is a visual, qualitative judgment, and we have not developed a formula for graft size related to ideal annulus size. Sleeve graft diameter is not based on cusp height, but rather the observation of suitable free edge contact of the leaflets. The sleeve graft size is usually about 7 to 10 mm larger than the diameter of the reduced annulus. The dilated sinuses occasionally had to be "stuffed" into the original style tube grafts, but conversion to the Valsalva graft (Vascutek Ltd, Renfrewshire, United Kingdom) has minimized this problem.
Procedure
Typically, after placement of the subannular horizontal mattress sutures, an annulus reduction suitable for leaflet coaptation and valve competence is estimated. A cylindrical Hegar dilator (Jarit Instruments, Hawthorne, NY) is placed through the valve to maintain the same annulus size reduction as the sleeve graft is then sized and seated. The subannular anchor sutures are delivered outward through the sleeve graft. The presized dilator prevents annular narrowing while the sutures are tied. Tying each subannular mattress suture produces about 1 mm of additional annulus reduction. With the original technique using 10 to 12 subannular sutures, annulus constriction was a major concern and the indwelling dilator was paramount. The modification using a total of only 3 to 4 subannular sutures greatly decreases the likelihood of annular constriction, but it is still imperative to avoid annular narrowing (Fig 1). In smaller roots, a Hegar dilator is placed intermittently through the distal suture line to avoid narrowing the repair at the sinotubular junction (STJ).
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The proximal repair is firmly anchored by these 4 subannular sutures, and no evidence of sinus bulging below the graft has been observed on echo, computed tomography (CT) scan, or magnetic resonance imaging. No graft migration has occurred, and no coronary artery kinking, distortion, or aneurysm formation has been observed at the coronary keyholes in the graft. With bicuspid valves, a subannular suture is placed under each of the 2 commissures, and 2 additional subannular sutures are placed roughly opposite each other half way between the commissure sutures. Few bicuspid valves were used for this procedure, having only trace or mild insufficiency, and no prolapse occurred after annulus reduction.
Only 2 patients in this consecutive series received Valsalva grafts, although we now use this graft almost exclusively. Anatomic and theoretic factors involved in the change to the Valsalva graft are discussed in the "Comment" section.
Echocardiographic Measurements
All patients had typical echocardiographic central jet AI. Echo measurements included grade of aortic valve insufficiency on a scale of 0 to 4 (0 = none, 1 = trace, 2 = mild, 3 = moderate, 4 = severe), LVEF, LV end-systolic (LVESD) and end-diastolic diameter (LVEDD), and STJ diameter. The maximum aortic root size at the sinuses was typically 15 to 25 mm larger than the STJ diameter on preoperative CT scan, but the TTE measurement of the root diameter at the sinuses was often problematic due to an inadequate ultrasound window or inability to obtain satisfactory transverse root orientation. Therefore, root diameter at the sinuses was not considered a reproducible or reliable dimension and STJ was measured instead.
TTEs were performed or evaluated by University of Florida cardiology faculty members not involved in the study. All patients underwent TTE a mean of 13 days (range, 0 to 34 days) preoperatively and 6.8 days (range, 4 to 9 days) postoperatively. The timing of annual TTE examinations was defined as annually ± 45 days from the date of the operation. New York Heart Association functional class is a late and subjective indicator of worsening AI, consistently lagging changes in LV dimensions, and was not used in this study.
Statistical Analysis
Echocardiographic data were retrieved preoperatively and at 1 week and 1, 2, and 3 years postoperatively. Analysis of each data point for statistical significance was made against the immediately preceding time point, except where otherwise stated. A paired t test was used to separate means between the respective data points, significance was set at p 
0.05. Categoric data were expressed as percentages, and the Fisher exact or 
2 test was used as appropriate for comparison of groups. All statistical analyses were done using SAS 9.1.3 software (SAS Institute; Cary, NC) and reported as mean and standard deviation.
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Results |
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TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
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LV dimensions and AI are expressed in Figure 4.
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The 4 late deaths were not caused by valve failure, ascending aortic disruption, or proximal coronary artery distortion. No patient has required reoperation or reintervention on the aortic valve, proximal coronary arteries, or ascending aorta. Two patients in the cohort were unavailable for follow-up after 12 and 13 months respectively. Records show that both are alive, but additional data could not be obtained. No study group patient has been lost to follow-up. Of 18 patients in the study group, 18 were at risk at 2 years and 10 at 3 years. Kaplan-Meier curves were not constructed because the follow-up period was too short to be meaningful.
Antithrombotic management was aspirin 81 mg daily in all patients. Anticoagulation with unfractionated heparin, enoxaparin, or warfarin was not used, including patients with temporary in-hospital postoperative atrial fibrillation.
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Comment |
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TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
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Historically, the bioprosthetic valve conduit has been a widely used solution for avoiding anticoagulation while effecting a reliable reconstruction of the root and ascending aorta. The predictable durability of modern bioprosthetic valves compared with repaired aortic valves is attractive, but the inevitable valve redo operation may be formidable. For this reason, the tissue valve conduit reconstruction has been largely replaced by aortic root remodeling or valve reimplantation procedures [3, 4]. Growing evidence of sinus expansion after root remodeling procedures has made valve reimplantation the more appealing repair, particularly after de Oliveira and colleagues [8] observed in Marfan patients that 96% remained free of AI exceeding 2+ a mean of 8 years after a reimplantation valve-sparing procedure, but only 71% were free of AI exceeding 2+ after root remodeling.
Expansion of the residual sinus wall may be unique to the Marfan population, but the sinuses rather than the leaflets appear to be the more unpredictable component in root remodeling procedures. Like other reimplantation techniques, with the sleeve repair the entire root resides within an unyielding conduit, avoiding unpredictable sinus expansion or speculation about the expression of a patient's genotype for connective tissue disorders. Dimensional stability of the sleeved root is confirmed by the unchanged STJ diameter from 1 week to 3 years (p = 0.70). Further, the sleeve accomplishes a stable repair of the aortic root and also avoids the need for radical sinus resection and coronary artery transfer. Aortic valve reoperations after some root reconstruction techniques may be complicated by numerous suture lines from the Dacron graft to the aorta, but although no Florida sleeve patients have undergone reoperation yet, the dissection inside the root should not be hampered by exposed Dacron, and the annulus should be large and fully intact.
Reduction of AI grade from a mean of 2.61 ± 0.78 preoperatively to 1.39 ± 0.85 postoperatively was observed after repair, and AI remained unchanged at 1.39 ± 0.84 after 1 year (p = 0.82). AI increased significantly to 1.72 ± 0.89 at 2 years (p = 0.03) and then decreased to 1.66 ± 0.50 at 3 years (p = 0.34). The AI grade at 3 years was not statistically different from 1 week postoperatively (p = 0.59), but the trend toward increasing AI is concerning and not easily explained by factors such as minor increases in blood pressure with increased age or decreased pulse rate after β-blocker manipulation related to the former.
LVEDD is the a well accepted early indicator of worsening AI [6, 19], and the sustained reduction of LVEDD for 32 ± 6.3 months supports the durability of the valve repair. LVESD also remained stable 32 months after the sleeve repair, and although not a dimension affected early in the course of worsening AI, it is a sensitive indicator of LV systolic dysfunction and good corroborating evidence of acceptable aortic valve competence [6, 19].
Technical Considerations
David and colleagues [20] have described the preservation of leaflets from roots up to 50 mm using sinus resection and reimplantation techniques. We have found the native leaflets of roots up to 65 mm to be predictably suitable for sleeve repair. The sleeve repair in larger roots requires considerable patient selection, because the leaflets may be attenuated and less suitable for salvage using simple annulus and STJ reduction.
Significant transverse expansion of the sleeve grafts was not observed after the first postoperative week in this series, but early dilation remains a concern. The expansion of woven Dacron tube grafts after thoracic aortic replacement has been extensively studied and recently reported by Etz and colleagues [21] in a retrospective review of CT scans of 547 patients in whom thoracic aortic grafts were placed during a 20-year period at a single institution. In the ascending aorta, rapid expansion averaging 17% occurred within 7 days of implantation, but thereafter, expansion averaged 2.8% per year for 18 months and decreased to 0.9% each year after. The authors speculated that graft expansion may contribute to recurrent AI after aortic valve reimplantation procedures, and choice of graft size may need to be reduced accordingly.
The behavior of grafts external to the arterial blood flow is not as well studied. Grafts exterior to the circulation have been used as preventive wraps around small aneurysms [15]. In one large series in which Dacron mesh was used to band ascending aortic aneurysms, the mean increase in diameter was 2.6 mm, or 8%, over 5.7 years [22]. Mesh is probably more prone to stretching than tube grafts, and the extent of expansion of periaortic Dacron tube grafts in extravascular locations remains unknown. The present sleeve series used as baseline the aortic diameter measured by TTE at mean 6.8 ± 1.2 days postoperatively and would have missed the initial rapid expansion that was observed [21]. The mean manufacturer's recorded size for the 18 grafts used in the study group was 32.3 mm compared with the sinotubular junction size of 36.9 ± 5.9 mm measured by ultrasound 1 week postoperatively, an expansion of about 4.6 mm or 14%. Ultrasound measurements of large abdominal aortic aneurysms have been shown to overestimate aortic diameter by as much as 5 mm [23], but it is equally likely our measurements just confirm the Etz and colleagues' [21] finding of the early 17% expansion of Dacron tubes within 7 days of implantation in the thoracic aorta. Similar to this study, Etz and colleagues used the manufacturer's listed graft size as the baseline for comparison over time.
Although the degree of expansion of the sleeve graft that resides outside of the central circulation is not known, the possibility of worsening AI due to lateral displacement of the leaflets from graft expansion requires close follow-up. Postoperative AI after the sleeve repair is uniformly central jet, and this may reflect simple graft expansion as has been speculated [21]. If early graft expansion is found to cause the mild trend toward increasing AI at 3 years in this series, it may be necessary to downsize the sleeve graft to equalize the observed 14% initial expansion in this series. The absence of an increase of LVEDD suggests this low-grade postoperative AI is not physiologically detrimental, but a completely competent valve should be obtainable.
A few isolated cases are reported in which the aortic wall inside a tightly wrapped external Dacron graft has become thin and attenuated [24] or ruptured [25], but large, long-term follow-up studies of external Dacron wraps for aneurysms have not found this to be a problem [15].
Use of the Valsalva-design graft appears to be a prudent modification to our original Florida sleeve article [10]; theoretically promoting sinus expansion, improving coronary blood flow, and decreasing leaflet stresses [13, 26, 27]. The results of clinical reports after root remodeling and valve reimplantation procedures have been extensively reviewed [28], and surgeons and engineers have developed models demonstrating increased stresses on aortic leaflets when physiologic sinus and ascending aortic pulsatile expansion is decreased or eliminated [29, 30]. It is generally accepted that the Windkessel effect of the ascending aorta and the natural expansion of the sinuses absorbs some of the force placed on the aortic leaflets during diastole, functionally providing recoil like an elastic reservoir [31]. The sleeve procedure retains the aortic sinuses, but the rigid Dacron sleeve may minimize the benefit of sinus expansion.
Limitations
A major consideration in the interpretation of postoperative echocardiographic dimensions in this series is the unknown contribution of pharmacologic unloading after valve repair. Long-term data about patient medications were not sufficiently available to assess the possible contribution of vasodilators and sympathetic suppression on the improvement of LV geometry in this study. Vasodilators may be immediately effective for the reduction of pulmonary congestion in acute AI, but considerable evidence shows that common vasodilators such as nifedipine, enalapril, or hydralazine are no more effective than placebo in preventing the chronic progression of LV failure in patients with isolated AI [32]. Carabello [33] has also emphasized the lack of data supporting vasodilators in the prevention of LV dysfunction in chronic aortic regurgitation, and no drug combination has been proved to delay the need for valve replacement or to affect morbidity or mortality in chronic AI [34]. The benefit of β-blockers in isolated AI is even less well confirmed [35]. It is probably reasonable to assume the improvement and maintenance of LV dimensions in the sleeve study group is due mainly to a durable valve repair.
Conclusion
The Florida sleeve procedure for valve-sparing correction of functional type I AI associated with aortic root aneurysms is dimensionally stable for at least 2 years. A minor increase in AI between the first and second postoperative years warrants continued close follow-up. The preservation of LVEDD for 3 years after repair is encouraging and supports the continued use of this procedure in closely monitored series. The lesser complexity of the Florida sleeve repair compared with other reimplantation procedures remains an incentive for continued clinical investigation.
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Discussion |
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TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
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Aortic valve repair and replacement of the aortic sinuses in patients with aortic root aneurysms is a challenging and gratifying procedure. The technical demands of these repairs have challenged many surgeons and, as a result, many times a perfectly good aortic valve is thrown away and a valved conduit is put in place despite a normal aortic valve. A technically simpler approach with predictable results would make valve-sparing procedures more popular and thus the reason that, Tom, you developed the Florida sleeve operation.
Preservation of the native aortic valve requires predictable reduction of the aortic annulus, the sinuses of Valsalva, and, of course, the sinotubular junction. Reduction of each of these structures has to result in a sufficient zone of coaptation for the leaflets, and you appear to be accomplishing that.
Myself, to accomplish these stable reductions, I have used the Stanford modification of the David V operation with good reproducible results. To me, the advantages include fabulous exposure of all of these structures that you have to reduce, the ability to rebuild the aortic root as you go, and, most importantly, the impressive normal 4D [four-dimensional] MRI [magnetic resonance imaging] profiles demonstrated by Dr Miller at Stanford.
I have a few questions for you. First, have you tried other methods of aortic valve repair when fixing aortic root aneurysms? Did you encounter difficulties? Specifically, what were they and what made you think to develop this particular procedure?
I looked at your manuscript and you had a picture of the operation, and you use only 4 sutures in the aortic annulus. And the concept that many aortic root surgeons have is that it is the fibrous portion of the aortic annulus that dilates and not the muscular portion, and therefore, you can selectively reduce the fibrous portion for what we would hope would be a good long-term result. Tell me what you think about that and your opinion.
Also, handling the coronary arteries, I have mobilized a lot of aortic roots and always do it with the coronaries mobilized and then the root beneath mobilized, and it seems difficult to me conceptually to have the area between, for instance, the left coronary artery and the annulus sufficiently mobilized to get the graft around there well. So could you tell us some of the tricks of that.
And finally, to follow on a theme that Dr Cameron started, I quibble with the name, Florida sleeve. I am from the University of Florida, I don't live in Florida anymore, and I am part of the Gator Nation. Now, gator is a way better name for this because a gator goes from the ears to the shoulders, it is circular, and it looks a lot more like an aortic root than a sleeve. So how about considering changing the name?
DR MARTIN: Thank you for your discussion, Dr Kon. The first question is have we tried other methods? Yes. We did about 50 David procedures. We did David Is and David IIs. We never made it to the David V. And, yes, we did find that somewhat of a daunting task. We had good results. I am an Aggie. I am from Texas, I am from Texas A and M. I found that I was measuring, getting my ruler out and doing all those measurements and calculations, and then I would always listen to Kevin Accola, who is standing back there, and I would throw out those numbers and I would get a 30 graft, and then we were putting in a straight tube. It was actually, we thought, a rather difficult procedure, and the whole reason that we tried to come up with something different was to hopefully create something a little bit easier for the surgeon to be able to do, that maybe everyone in this room could do, and more valves would be salvaged. The David procedures were outstanding procedures. If you know how to do them and you get good results, by all means, keep doing them. Our pediatric surgeon at the University of Florida still does Davids, and I have gotten him to do one sleeve, only because he had to. So, yes, we did try those and that is why we did it.
As to the number of sutures, we began in the beginning using 10–12 sutures, I mean, circumferential sutures just like a David because that is what we were used to doing. What we rapidly realized was that we really didn't need those. A large percentage of the patients we were doing these operations on did not have dilated annuluses. We certainly didn't need them on the muscular portion. In trying to maintain that circumferential suture line at the bottom, we actually had a fairly high rate of heart block, which is purely technical. And so we began using less and less sutures. If we have a normal annulus, and I consider a normal annulus to be 26 mm or under, then we may narrow that annulus only about 1 to 2 mm, somewhere in the 24-mm range, with a Hagar dilator in the middle. We use typically 4 to 6 sutures, and if the annulus is dilated at all, we put more sutures along the fibrous portion in order to narrow the fibrous portion. Again, the majority of these patients do not have dilated annuluses and really don't need a whole lot except to anchor the graft.
In terms of the coronary mobilization, I think if you tried it you would find it is really not difficult. You mobilize underneath there, you start on each side, you start and then just dissect down, all the way down, and in the left coronary it is particularly easy. You come around between the aorta and the cava and the dome in the left atrium. You mobilize that area, and you come right to the left main and you can get underneath it. You then come between the aorta and the pulmonary artery, and you dissect down to that aortopulmonary artery fibrous continuity, follow that inferiorly, and it gets right underneath there, put a little right angle underneath there; it works really well, and the right is really pretty easy, very similar.
As to the name, you know, Florida sleeve came up somewhere. I don't know where it came up, but there it is.
DR KEVIN D. ACCOLA (Orlando, FL): Tom, very nice presentation as you all do such a great job up there with all your aortic work. Two questions real quick. One, is there any sinotubular junction size or sinus of Valsalva aneurysm size or is there discrepancy of the sinus of Valsalva that would be prohibitive to do this procedure? In other words, any anatomy that would make you do something different?
Two, you didn't mention anything about the bicuspid valve, which we have had numerous discussions about before, but I am curious if this has changed or altered your management of the bicuspid valve? Thank you.
DR MARTIN: We have been asked those questions, particularly about the size of the sinuses, and can you really stuff a 6-cm or a 7-cm root into a 32- or 34-mm Valsalva graft? And, yes, you can do it. It doesn't look that pretty when you are doing it, but when you get done, the echos all look good and they look good in the long-term. The only anatomic problems we have had in terms of doing this operation have been patients that have had abnormal coronaries and where the coronaries sit up high. Sometimes the coronaries may ride up, particularly in the Marfans, all the way up above the sinotubular junction, and if they really get high, then we have had to do some modification. In a couple of patients, we have actually reverted back to a David in those procedures.
As to the bicuspid aortic valve, we save bicuspid aortic valves only if the valve leaflets are completely normal and there is no prolapse. I know there are a lot of things you can do, but this is just what we do. We don't save anything other than that. I think in a bicuspid valve you have to remember in many of those the suspension mechanism is completely different than a tricuspid valve, and you can't really pull that sinotubular junction back in and you have to try and maintain a little bit larger sinotubular junction.
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This article has been cited by other articles:
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  T. E. David, M. Maganti, and S. Armstrong Aortic root aneurysm: Principles of repair and long-term follow-up J. Thorac. Cardiovasc. Surg., December 1, 2010; 140(6_suppl): S14 - S19. [Abstract] [Full Text] [PDF]
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 L. G. Svensson, M. Cooper, L. H. Batizy, and E. R. Nowicki Simplified David Reimplantation With Reduction of Anular Size and Creation of Artificial Sinuses Ann. Thorac. Surg., May 1, 2010; 89(5): 1443 - 1447. [Abstract] [Full Text] [PDF]
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R. Hetzer, T. Komoda, S. Komoda, F. Berger, and M. Huebler New Aortic Root Remodeling Surgery in Aortic Root Aneurysm Ann. Thorac. Surg., April 1, 2010; 89(4): 1260 - 1264. [Abstract] [Full Text] [PDF]
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H. Izumoto The Florida Sleeve Repair: Letter 2 Ann. Thorac. Surg., January 1, 2010; 89(1): 343 - 343. [Full Text] [PDF]
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A. Gamba, M. Merlo, and M. Triggiani Promising Early Results of Periaortic Root Remodeling With the Valsalva Graft: Letter 1 Ann. Thorac. Surg., January 1, 2010; 89(1): 342 - 343. [Full Text] [PDF]
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P. J. Hess Jr, P. K. Harman, C. T. Klodell, T. M. Beaver, C. G. Tribble, and T. D. Martin Reply Ann. Thorac. Surg., January 1, 2010; 89(1): 343 - 344. [Full Text] [PDF]
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LVEDD: preoperatively to 1 week [p = 0.05] and 1 week to 1 year [p = 0.008]. 
LVESD: preoperatively to 1 week [p = 0.002] and 1 week to 1 year [p < 0.001]. 
AI: preoperatively to 1 week [p < 0.001], and 1 year to 2 years [p = 0.03]. One week to 3 years [p = 0.594].)