Functional aortic annulus 3-dimensional remodelling during bicuspid aortic valve repair: complete external and internal annuloplasty

The internal geometric ring provides full three-dimensional annular stability while minimizing the dissection of the aortic root, pulmonary artery and right ventricle and avoids reimplanting the coronaries. The external annuloplasty provides a secondary stabilization of the easily accessed fibrous portion of the annulus using the sutures for the internal annuloplasty device and minimizes the sutures above the leaflets. Together they form a complete remodelling of the ventriculo-aortic junction following its exact course. The junction together with stabilization of the subcommissural triangles defines functional aortic annulus remodelling. External annuloplasty supports the virtual basal ring.

Bicuspid aortic valve repair: outcomes after 17 years of experience

OBJECTIVES

This study presents the results of 17 years of experience with bicuspid aortic valve (BAV) repair and the analysis of factors associated with repair failure and early echocardiographic outcome.

METHODS

Between 2003 and 2020, a total of 206 patients [mean age: 44.5 ± 15.2 years; 152 males (74%)] with BAV insufficiency with or without aortic dilatation underwent elective aortic valve repair performed by a single surgeon with a mean follow-up of 5 ± 3.5 years. The transthoracic echocardiography examinations were reported.

RESULTS

There were no deaths during the hospital stay, and all but 1 patient survived the follow-up period (99.5%). Overall, 10 patients (5%) developed severe insufficiency and 2 (1%) developed aortic dilatation requiring reoperation. Freedom from reoperation at 7 years reached 91.8%. Type 2 BAV configuration [hazard ratio (HR) 3.9; 95% confidence interval (CI): 1.01-60; P = 0.049], no sinotubular junction remodelling (HR 7; 95% CI: 1.7-23; P = 0.005), no circumferential annuloplasty (HR 3.9; 95% CI: 1.01-64; P = 0.047) and leaflet resection (HR 5.7; 95% CI 1.2-13. P = 0.017) have been identified as a risk factor of redo operation. Parameters of the postoperative left ventricle reverse remodelling improved significantly early after the operation and later at 2 years evaluation.

CONCLUSIONS

The repair of BAV offers good short- and mid-term results providing a significant reverse left ventricular remodelling. Type 0 BAV preoperative configuration, circumferential annuloplasty and sinotubular junction remodelling are associated with better repair durability.

Leaflet Dimensions as a Guide to Remodeling Annuloplasty During Aortic Valve Repair

OBJECTIVE

In chronic aortic insufficiency (AI), the method and degree of annular downsizing required to achieve durable coaptation in aortic valve repair (AVr) remains poorly defined. This study evaluated the relationship between leaflet size and annular diameter to predict adequate annular sizing in remodeling AVr.

METHODS

Under regulatory supervision, 74 patients with chronic tri-leaflet AI underwent AVr using ring annuloplasty and leaflet reconstruction. Fifty-four (73%) had ascending aortic (n = 25) and/or root (n = 29) aneurysms, and aortic grafts were sized 5 to 7 mm larger than the rings. Intraoperatively, leaflet free-edge length (FEL) was measured with special ball sizers positioned in the coronary sinus, and "normal" annular diameter was predicted from the validated formula: Required "normal" diameter = FEL/1.5. "Normal" annular diameters predicted from FEL were compared with pathologic diameters measured intraoperatively with Hegar dilators, and both were correlated with gender, age, and BSA.

RESULTS

Average age was 62.1 ± 13.3 years (mean ± SD), 73% (54/74) were male, and 96% (71/74) had moderate-to-severe AI. All patients had annular dilatation, with a pathologic diameter 26.6 ± 2.3 mm before repair, and a predicted "normal" diameter of 21.7 ± 1.7 mm (P < 0.001). Both predicted and pathologic annular diameters were larger in men (P < 0.001), but no relationship existed with age. BSA correlated with both predicted and pathologic diameters, although variability was large.

CONCLUSIONS

Based on a simple validated method to predict "normal" annular diameter, all patients with chronic AI have some degree of annular dilatation. This finding implies that most AVr should include annuloplasty, with adequate and precise annular reduction based on leaflet size.

The evaluation of annuloplasty in bicuspid aortic valve repair using cardiac magnetic resonance

Background

The incompetent bicuspid aortic valve (BAV) can be replaced or repaired using various surgical techniques. This study sought to assess the efficacy of external annuloplasty and postoperative reverse remodelling using cardiac magnetic resonance (CMR) and compare the results of external and subcommissural annuloplasty.

Methods

Out of a total of 200 BAV repair performed between 2004 and 2018, 21 consecutive patients (median age 54 years) with regurgitation requiring valve repair with annuloplasty without concomitant aortic root surgery were prospectively referred for CMR and transthoracic echocardiography (TTE) one year after the operation. Two aortic annulus stabilization techniques were used: external, circumferential annuloplasty (EA), and subcommissural annuloplasty (SCA).

Results

11 patients received EA and 10 patients were treated using SCA. There was no in-hospital mortality and all patients survived the follow-up period (median: 12.6 months (first quartile: 6.6; third quartile: 14.1). CMR showed strong correlation between postoperative aortic recurrent regurgitant fraction and left ventricular end-diastolic volume (r = 0.62; p = 0.003) as well as left ventricular ejection fraction (r = -0.53; p = 0.01). Patients treated with EA as compared with SCA had larger anatomic aortic valve area measured by CMR (3.5 (2.5; 4.0) vs. 2.5 cm² (2.0; 3.4); p = 0.04). In both EA and SCA group, aortic valve area below 3.5 cm² correlated with no regurgitation recurrency. EA (vs. SCA) was associated with lower peak transvalvular aortic gradients (10 (6; 17) vs. 21 mmHg (15; 27); p = 0.04).

Conclusions

The repair of the bicuspid aortic valve provides significant postoperative reverse remodelling, provided no recurrent regurgitation and durable reduction annuloplasty can be achieved. EA is associated with lower transvalvular gradients and higher aortic valve area assessed by CMR, compared to SCA.

Different techniques for aortic valve repair and the associated root reconstruction - prospective long-term follow-up of the first 100 patients

INTRODUCTION

The advantages of aortic valve and aortic root reconstructive surgery include the provision of natural postoperative valve hemodynamics and the avoidance of prosthetic valve-related complications. A systematic approach based on functional classification of aortic regurgitation allows standardization and reproducibility. Its potential applicability, however, is limited by the relative lack of long-term follow-up data.

AIM

To achieve the long term results of aortic valve and root repair in prospectively recruited group of 100 patients operated on during first seven years.

MATERIAL AND METHODS

Between the years 2003 and 2013, 225 consecutive patients (175 male, 50 female, mean age 51.3 years) with severe aortic regurgitation and aortic root enlargement underwent aortic valve repair or sparing surgery. The first 100 patients operated between 2003 and 2009 were prospectively enrolled in the study in order to achieve a 105-month follow-up. They underwent aortic valve repair and associated aortic root reconstruction. This prospective study is aimed at assessing the major endpoints of overall survival and freedom from reoperation. Additionally, log-rank testing for the risk factors associated with overall mortality, reoperation, and aortic valve repair failure was performed.

RESULTS

Among 225 patients, early mortality occurred in the case of 5 patients (2.2%), while 6 (2.5%) patients experienced early valve failure. In a prospective analysis performed on the first 100 patients, long-term results achieved with Kaplan-Meier analysis showed a survival rate of 93% and freedom from reoperation at the level of 91.3%. The risk factors for overall mortality included NYHA class, creatinine level, and perioperative root replacement as reimplantation. Redo operation was associated with bicuspid aortic valve and perioperative leaflet resection with pericardial patch repair.

CONCLUSIONS

One hundred and five month follow-up data from this prospectively analyzed cohort of patients prove that aortic valve repair associated with aortic root reconstruction can be performed with satisfactory results.

Long-term outcomes after aortic valve repair and associated aortic root reconstruction

BACKGROUND AND AIM OF THE STUDY

The advantages of aortic valve repair and root reconstruction include the maintenance of natural valve hemodynamics and an avoidance of prosthetic valve-related complications. However, the general acceptance of valve reconstruction currently may be limited by a paucity of long-term follow up data from only a few centers. The study aim was to supplement existing outcome information for aortic valve repair.

METHODS

Between 2003 and 2012, a total of 150 consecutive patients (119 males, 31 females; mean age 51.1 years) with significant aortic regurgitation and aortic root enlargement underwent aortic valve repair and associated root reconstruction. The same prospective selection criteria and systematic valve repair approaches were followed throughout the study. Root management consisted of either root remodeling or reimplantation with Dacron prostheses. Kaplan-Meier techniques were used to assess major end-points of all-cause mortality, reoperation, and repair failure. Univariable log-rank testing identified any associations between risk factors and major events.

RESULTS

The early mortality rate was 2.7% (n = 4), and early repair failure rate 3.3% (n = 5). At a mean follow up of 43.6 months (1st, 3rd percentile, 17.8, 78.0 months), the survival rate was 93% and freedom from reoperation 91%. Univariable risk factors for mortality included advanced preoperative NYHA class and a requirement for root replacement. Repair failure and reoperation were associated with bicuspid valve anatomy, subcommissural annuloplasty, leaflet resection with pericardial patching, and Gore-Tex leaflet reinforcement.

CONCLUSION

The present data, acquired from a prospective cohort of patients undergoing aortic valve repair and root reconstruction, reinforced the satisfactory late results obtained with valve reconstruction. These findings also support a broader application of aortic valve repair in future patients.

Early Regional Assessment of LV Mass Regression and Function after Stentless Valve Replacement: Comparative Randomized Study

Early regional performance and hypertrophy regression after stentless aortic valve replacement are still incompletely characterized. We compared early postoperative changes of segmental thickness and function after stentless and stented aortic valve replacement as assessed by cardiac magnetic resonance (CMR). In 16 patients randomly assigned to stented (Mosaic, 8 patients) and stentless (Freestyle, 8 patients) groups, 4 parallel short-axis images at the level of the apex (slice 4), midventricle (slices 2-3), and mitral valve (slice 1) were obtained with a 1.5 T CMR scanner (Magnetom Sonata, Siemens) before and 1 month after surgery. Cine images were obtained using an echo gradient sequence. Left ventricle mass was calculated as the difference between the left ventricular end-diastolic volume at the epicardial and endocardial borders multiplied by a myocardium density factor (1.05). Each slice was divided into 8 segments (octants) from anterior (octant I-II) to septal (octant V-VIII). A total of 32 segments encompassed the entire heart. From each of these elements end diastolic thickness and systolic function (fractional thickening) were calculated. In stentless valves significant reduction of septal octant thickness on the midventricular slice was noted. There was no difference in regional systolic function-segment thickening. In stented valves no segmental thickness changes were observed. In stentless valves there was early postoperative thickness reduction of septal segments at the midventricular level. However, this finding did not coincide with changes in segmental function.

Primary OPCAB as a strategy for acute coronary syndrome and acute myocardial infarction

BACKGROUND

Conventional coronary artery bypass graft (CABG) surgery using cardiopulmonary bypass (CPB) carries higher mortality and morbidity for patients undergoing surgery during acute coronary syndrome (ACS). The aim of this retrospective study was to evaluate potential benefits of avoiding CPB by instead performing off-pump CAB (OPCAB) during surgery on patients in ACS.

METHODS

Among 624 patients who underwent OPCAB between January 1999 and June 2001, 143 underwent surgery during ACS (group 1). The ACS patients in group 1 were divided into 2 subgroups: 66 underwent surgery during acute myocardial infarction (AMI group) and 77 during unstable angina classified as class III or IV according to the Braumwald classification (unstable coronary artery disease [CAD] group). Group 2 (the elective CAD group) consisted of 481 patients who underwent isolated elective OPCAB during the same time period.

RESULTS

Overall 30-day mortality was 4.9% (n = 7) for the ACS group and 0.83% (n = 4) for the elective CAD group (P < .0001). Differences between groups were found in use of inotropes, intraaortic balloon pump, and subsequent conversion of OPCAB to CPB (P < .0001, P < .01, and P < .03, respectively), as well as use of blood transfusion (P < .0003). Multivariate logistic regression analysis for 641 patients revealed ACS (P < .015), AMI (P < .019), renal failure (P < .017), and left ventricle aneurysm (P < .028) as independent risk factors for 30-day mortality in ACS reoperation (P = .02), whereas in AMI renal failure (P = .02) appeared to be an independent risk factor.

CONCLUSIONS

OPCAB is a valuable treatment strategy in ACS patients; however, it carries significant mortality and morbidity. Careful preselection and timing of intervention are required in order for patients to fully benefit from the OPCAB strategy.

Dysfunction of left ventricle as an indication for off-pump coronary artery bypass grafting

BACKGROUND

Coronary artery bypass grafting (CABG) with cardiopulmonary bypass carries significant risk for patients with severe left ventricular (LV) dysfunction.

METHODS

Between 1997 and 2000, 240 patients underwent OPCAB. The patients were retrospectively divided into 2 groups with regard to LV function. Group 1 consisted of 90 patients with ejection fraction (EF) <35% and grou p 2 of 150 patients without severe LV impairment and EF >35%. Patients were compared for preoperative risk factors, perioperative mortality, and postoperative complications.

RESULTS

Preoperative expected mortality according to EuroSCORE was higher in group 1, 5.95, compared with group 2, 2.66 (P =.0005). A few preoperative risk factors were more common in group 1: urgent operation (P =.00001), unstable angina (P =.0018), Canadian Cardiovascular Society class (P =.001), myocardial infarction (P =.0001), and peripheral arteriopathy (P =.0006). Mean number of grafts was 1.51 in group 1 and 1.55 in group 2 with the same internal thoracic artery utilization. Perioperative drainage, anesthesia and intubation time, transfusion rate, and use of inotropes were comparable. Actual, nonadjusted mortality was 2.5% in group 1 and 1.4% in group 2 (P = not significant). Overall rates of postoperative complications were comparable; only use of an intraoperative balloon pump was more frequent in group 1 (P =.006). Postoperative stay was shorter in group 1 (P equals).

CONCLUSIONS

Off-pump CABG for patients with LV impairment is associated with surgical outcome similar to that among patients with normal LV function, in spite of the presence of unfavorable risk factors. Off-pump surgery with selective anterior (including right main) arterial revascularization can be indicated in the presence of poor LV function.

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 mid-term 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.

Hemodynamic performance after stented vs stentless aortic valve replacement

BACKGROUND

Stentless bioprostheses are anticipated to cause improved hemodynamics and increased longevity over stented bioprosthesis. We have compared echocardiographic analysis of stented bioprosthesis "Freestyle" with stented "Mosaic" bioprosthesis. Because of similar technology (0 pressure fixation, anticalcification) any differences may relate to stent.

METHODS

Twenty-eight patients undergoing AVR were randomly assigned to receive either stented or stentless. Echocardiograms, by means of M-mode and Doppler were performed early, 3-6 months and 1 year postoperatively.

RESULTS

The peak flow velocity was significantly lower in the stentless group, especially 1 week and 6 months after surgery. Mean transvalvular gradient dropped significantly in stentless group and did not change in stented group. EOA did not change significantly in either of groups. AoV velocity time integral was increasing in stentless group. LV mass had fallen significantly in both groups but degree of mass reduction was comparable.

CONCLUSIONS

There are marked improvements of stentless valves hemodynamics. However it is not necessary equal to higher degree of LV mass reduction during 1 year follow-up.

Does simultaneous antegrade and retrograde cardioplegia improve functional recovery and myocardial homeostasis?

BACKGROUND

The purpose of our research was to evaluate the functional recovery and homeostasis of myocardium during simultaneous continuous retrograde and antegrade cardioplegia versus continuous retrograde cardioplegia.

METHODS

Forty patients who underwent elective coronary artery bypass grafting (CABG) were prospectively assigned to two clinically matched groups and analyzed in respect to cardioplegia protocol. Group I consisted of 24 patients who received continuous retrograde blood cardioplegia; Group II consisted of 16 patients who received simultaneous continuous ante- and retrograde cardioplegia. Hydrogen ion release, carbon dioxide, lactate concentration oxygen content, and oxygen extraction were measured from coronary sinus effluent and from the arterial line before and after cross-clamping of the aorta. Median changes of these parameters were reported. Cardiac output was measured and left and right ventricle stroke works were calculated. Incidence of low cardiac output, ventricular fibrillation, raised cardiac enzymes, and ischemic changes on electrocardiogram (ECG) were noted.

RESULTS

In the simultaneous group, oxygen content and oxygen extraction recovered well after cross-clamping. The same parameters did not recover to the same extent in the retrograde group. These changes were notable between groups. Hydrogen ion, carbon dioxide, and lactate releases were comparable between groups. Trend toward better recovery of left ventricle stroke work index was encountered in the simultaneous group.

CONCLUSIONS

Viability of myocardium measured with oxygen utilization and functional recovery is better preserved with simultaneous antegrade and retrograde cardioplegia. However, there is no difference in anaerobic metabolism markers. Thus simultaneous ante- and retrograde cardioplegia is probably advantageous over retrograde alone.

"Mosaic" medtronic bioprosthetic valve replacement clinical results and hemodynamical performance

BACKGROUND

We report the mid-term results of a prospective trial of a new bioprosthetic valve. The Mosaic bioprosthesis consists of porcine aortic valve that has been cross linked ed in glutaraldehyde solution under zero-pressure fixation and treated with alpha amino oleic acid to reduce the potential for calcification.

METHODS

Mosaic bioprosthetic valve replacement was performed in 67 consecutive patients between January 1995 and August 1998. There were 37 patients having aortic valve replacement (AVR) and 30 having mitral valve replacement (MVR) who entered this study. The patients age ranged 56 to 86 years (mean 74.9); 38 were female and 29 were male; 44 were in NYHA grade 3 and 21 were NYHA grade 4. All mitral valve replacements were performed with total preservation of subvalvular apparatus. Echocardiographic assessment of valve and LV function were performed on 7th day, 6 months 1,2 and 3 years.

RESULTS

There was no hospital mortality. 3 year survival was 85.9+/-5.9% for AVR and 100% for MVR. Freedom from antithromboembolic related haemorrhage has been 96.7% for MVR and 91.9% for AVR. Freedom from the transient neurological event was 96.7+/-3.3% for MVR and 100% for AVR Freedom from structural valve failure, permanent thromboembolism, thrombosis or endocarditis has been 100% for both AVR and MVR. In AVR group left ventricle mass, left ventricle mass index significantly decreased, when cardiac index and effective orifice area increased significantly during study period. Transvalvular gradient did not change. In MVR group transvalvular gradient, effective orifice area and cardiac index did not change.

CONCLUSIONS

The valve was user friendly. The early results are very satisfactory. Echocardiography measurements after aortic valve replacement are showing very marked late postoperative remodelling of left ventricle. After mitral valve replacement there were exceptionally low transvalvular gradients, no left ventricle outflow tract obstruction.