Native Aortic Valve Disease Research Articles

Implanted size and structural valve deterioration in the Edwards Magna bioprosthesis.

The desire of patients to avoid anticoagulation, together with the potential of valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR), have resulted in the increasing use of bioprosthetic valves for aortic valve replacement (AVR). While patient-prosthesis mismatch (PPM) is known to be an adverse risk after AVR, few studies have addressed the effect of PPM on valve durability. This study evaluates the role of valve size and hemodynamics on long term durability after AVR with a Magna bioprosthesis. We performed a retrospective, single-center evaluation of patients who underwent a surgical AVR procedure between June 2004 through December 2022 using the Magna bioprosthesis. Perioperative information and long-term follow-up data were sourced from the institution's Society for Thoracic Surgeons Adult Cardiac Surgery Registry and outcomes database. Cumulative incidence of freedom from reintervention were estimated accounting for competing events. Group comparisons used Gray's test. Among 2,100 patients, the mean patient age was 69 years (range, 22-95 years), of whom 98% had native aortic valve disease, 32.5% had concomitant coronary bypass grafting, and 19% had mitral valve surgery. Median follow-up was 5.8 (1.9-9.4) years, during which 116 reinterventions were performed, including 74 explants and 42 VIV procedures. Nine hundred and twenty-eight patients died prior to reintervention. Incidence of all cause reintervention was 1.2%, 4.5%, and 11.7% at 5, 10, and 15 years, respectively. Smaller valve size was associated with worse survival (P<0.001), but not with reintervention. Higher mean gradient at implant was associated with increased late reintervention [sub-distribution hazard ratio: 1.016; 95% confidence interval (CI): 1.005 to 1.028; P=0.0047, n=1,661]. While reintervention rates are low for the Magna prosthesis at 15 years, the analysis is confounded by the competing risk of death. PPM, as reflected physiologically by elevated post-operative valve gradients, portends an increased risk of intervention. Further study is necessary to elucidate the mechanism of early stenosis in patients who progress to reintervention.

Evolving technology: the TRIFLO tri-leaflet mechanical valve without oral anticoagulation: a potential major innovation in valve surgery.

The aortic valve is the most frequently diseased valve and aortic stenosis (AS) is the most prevalent valvular heart disease in developed countries. The diseased native aortic valve can be replaced by either a biological or mechanical valve prosthesis. The main concerns relate to durability, the need for oral anticoagulants and the incidence of complications related to this medication. Experimental, computational and biomolecular blood flow studies have demonstrated that the systolic forward flow but also the reverse flow phase at the end of the systole and leakage during the diastolic phase is mainly responsible for platelet activation and thrombosis. Better design of mechanical prosthetic heart valves must ensure smooth closing during flow deceleration and must eliminate high-shear hinge flow during diastole to prevent life-threatening thrombosis. A novel tri-leaflet valve should combine the favorable hemodynamics and the durability of existing mechanical heart valves and eliminate the less favorable characteristics, including the extremely rapid closing. In this paper, we discuss some issues of current mechanical heart valve prostheses and present a new valve design with the potential for significant innovation in the field. The TRIFLO Heart Valve, is a rigid, three-leaflet central flow heart valve prosthesis consisting of an alloyed titanium housing, and three rigid polymer (PEEK) cusps. This valve has a physiological operating mode. During the forward flow phase, the intraventricular pressure opens the leaflets so that blood can freely flow through with little obstruction, and with the deceleration of the blood flow, the leaflets close early and smoothly, minimizing blood flow regurgitation, blood cell damage, and activation of the coagulation cascade. Pre-clinical studies have shown pretty favorable results and a first-in-man study should start very soon.

Native Aortic Valve Disease Progression and Bioprosthetic Valve Degeneration in Patients With Transcatheter Aortic Valve Implantation.

Major uncertainties remain regarding disease activity within the retained native aortic valve, and regarding bioprosthetic valve durability, after transcatheter aortic valve implantation (TAVI). We aimed to assess native aortic valve disease activity and bioprosthetic valve durability in patients with TAVI in comparison with subjects with bioprosthetic surgical aortic valve replacement (SAVR). In a multicenter cross-sectional observational cohort study, patients with TAVI or bioprosthetic SAVR underwent baseline echocardiography, computed tomography angiography, and 18F-sodium fluoride (18F-NaF) positron emission tomography. Participants (n=47) were imaged once with 18F-NaF positron emission tomography/computed tomography either at 1 month (n=9, 19%), 2 years (n=22, 47%), or 5 years (16, 34%) after valve implantation. Patients subsequently underwent serial echocardiography to assess for changes in valve hemodynamic performance (change in peak aortic velocity) and evidence of structural valve dysfunction. Comparisons were made with matched patients with bioprosthetic SAVR (n=51) who had undergone the same imaging protocol. In patients with TAVI, native aortic valves demonstrated 18F-NaF uptake around the outside of the bioprostheses that showed a modest correlation with the time from TAVI (r=0.36, P=0.023). 18F-NaF uptake in the bioprosthetic leaflets was comparable between the SAVR and TAVI groups (target-to-background ratio, 1.3 [1.2-1.7] versus 1.3 [1.2-1.5], respectively; P=0.27). The frequencies of imaging evidence of bioprosthetic valve degeneration at baseline were similar on echocardiography (6% versus 8%, respectively; P=0.78), computed tomography (15% versus 14%, respectively; P=0.87), and positron emission tomography (15% versus 29%, respectively; P=0.09). Baseline 18F-NaF uptake was associated with a subsequent change in peak aortic velocity for both TAVI (r=0.7, P<0.001) and SAVR (r=0.7, P<0.001). On multivariable analysis, 18F-NaF uptake was the only predictor of peak velocity progression (P<0.001). In patients with TAVI, native aortic valves demonstrate evidence of ongoing active disease. Across imaging modalities, TAVI degeneration is of similar magnitude to bioprosthetic SAVR, suggesting comparable midterm durability. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02304276.

Comparing quality of life and postoperative pain after limited access and conventional aortic valve replacement: Design and rationale of the LImited access aortic valve replacement (LIAR) trial

BackgroundSurgical aortic valve replacement (SAVR) via limited access approaches (‘mini-AVR’) have proven to be safe alternative for the surgical treatment of aortic valve disease. However, it remains unclear whether these less invasive approaches are associated with improved quality of life and/or reduced postoperative pain when compared to conventional SAVR via full median sternotomy (FMS). Study designThe LImited access Aortic valve Replacement (LIAR) trial is a single-center, single blind randomized controlled clinical trial comparing 2 arms of 80 patients undergoing limited access SAVR via J-shaped upper hemi-sternotomy (UHS) or conventional SAVR through FMS. In all randomized patients, the diseased native aortic valve is planned to be replaced with a rapid deployment stented bioprosthesis. Patients unwilling or unable to participate in the randomized trial will be treated conventionally via SAVR via FMS and with implantation of a sutured valve prosthesis. These patients will participate in a prospective registry. Study methodsPrimary outcome is improvement in cardiac-specific quality of life, measured by two domains of the Kansas City Cardiomyopathy Questionnaire up to one year after surgery. Secondary outcomes include, but are not limited to: generic quality of life measured with the Short Form-36, postoperative pain, perioperative (technical success rate, operating time) and postoperative outcomes (30-day and one-year mortality), complication rate and hospital length of stay. ConclusionThe LIAR trial is designed to determine whether a limited access approach for SAVR (‘mini-AVR’) is associated with improved quality of life and/or reduced postoperative pain compared with conventional SAVR through FMS.The study is registered at ClinicalTrials.gov, number NCT04012060.

The Gift of Double Mentoring

The Gift of Double Mentoring

Best Practices of Aortic Valve Replacement With the Edwards Intuity Elite Valve

The Edwards Intuity Elite (EIE; Edwards Lifesciences, Irvine, CA) valve system is a recent surgical aortic valve designed to expedite implantation, facilitate minimally invasive approaches, and provide low gradients, particularly in smaller valve sizes. The report reviews various best practices learned through experience with the EIE valve system. With its sealing frame designed to anchor and seal the valve after resection of the diseased native aortic valve, EIE use differs from that of conventional sutured valves. Critical technical aspects include patient selection, aortotomy and debridement, valve sizing, guiding suture technique and valve seating and deployment. In addition, special anatomic and pathologic conditions are considered, as well as intraoperative transesophageal echocardiography and postimplantation cardiac rhythm monitoring. These best practices simplify and standardize the use of the EIE valve system and may benefit surgeons adopting this valve.

The hospital results and 1-year outcomes of transcatheter aortic valve-in-valve procedures and transcatheter aortic valve implantations in the native valves: the results from the Swiss-TAVI Registry.

The SwissTAVI Registry includes all consecutive patients undergoing transcatheter aortic valve implantation (TAVI) and valve-in-valve (VinV) procedures for a failed bioprosthesis in Switzerland. We report the real world, all-comers, 30-day and 1-year outcomes of patients undergoing VinV and standard TAVI procedures. Prospectively collected data from the 2 groups (VinV and standard TAVI patients) were retrospectively analysed. In an adjusted analysis, in-hospital and 1-year outcomes of VinV patients were compared with those of patients undergoing TAVI for native aortic valve disease in the same registry. A subanalysis of VinV procedures in stenotic or regurgitant bioprosthesis was also performed. Between February 2011 and December 2016, 4599 and 157 consecutive patients underwent TAVI in native aortic valves and VinV procedures in degenerate bioprosthesis, respectively. VinV patients were younger (78 ± 9.1 years vs 82.2 ± 6.3 years; P < 0.001) but at a higher risk for surgery (the logistic EuroSCORE: 28.48 ± 15.3% vs 18.2 ± 13.6%; P < 0.001; the Society of Thoracic Surgery (STS) score: 6.4 ± 5% vs 5.5 ± 4.3%; P = 0.008). Valve predilatation was less frequently performed during VinV procedures (22.9% vs 69.1%; P < 0.001), and the hospital stay was shorter after VinV procedure (8.46 ± 4.2 days vs 9.83 ± 6 days; P = 0.005). VinV patients showed higher predischarge transvalvular mean gradients (14.14 ± 7.9 mmHg vs 8.42 ± 5.0 mmHg; P < 0.001), smaller mean valve surface area (1.54 ± 0.7 cm2 vs 1.83 ± 0.5 cm2; P < 0.001) and a lower risk of moderate/severe paravalvular leak (1.3% vs 5%). Post-procedural kidney injury (1.3% vs 4.8%; P = 0.06) and new pacemakers for conduction abnormalities (3.3% vs 18.5%; P < 0.001) were higher after TAVI. All-cause mortality and cardiovascular mortality at 30 days were similar between the 2 groups (1.9% vs 3.8%; P = 0.242 and 1.9% vs 3.4%; P = 0.321), whereas after 1 year, all-cause mortality was lower for VinV patients (6.8% vs 13%; P = 0.035). The bioprosthetic valve size correlated inversely with postoperative gradients after VinV procedures. VinV aortic procedures showed favourable 30-day and 1-year clinical outcomes compared with TAVI procedures for the native aortic valve disease. Despite higher transvalvular mean gradients following VinV implants, this appears not to impact the early clinical outcomes.

Direct Oral Anticoagulant Use in Valvular Heart Disease

Direct oral anticoagulants (DOACs) are indicated by the European Medicines Agency and US Food and Drug Administration for stroke prevention in patients with nonvalvular atrial fibrillation (AF). The role of DOACs in patients with AF and concomitant valvular heart disease (VHD) is less clear. Recent subanalyses of randomized controlled trials and meta-analyses have evaluated the role of DOACs in patients with AF and VHD. Patients with native aortic valve disease, tricuspid valve disease, or mitral regurgitation will be the primary focus as these represent the majority of VHD represented in the DOAC AF trials. Limited data exist on the role in patients with rheumatic mitral stenosis, mechanical heart valves, and mitral valve repair. This review provides the current clinical and scientific data pertaining to the safety and efficacy of DOAC use in patients with VHD.

Clinical Implication of Transaortic Mitral Pannus Removal During Repeat Cardiac Surgery for Patients With Mechanical Mitral Valve.

This study aimed to evaluate the safety and feasibility of transaortic mitral pannus removal (TMPR).Methods and Results:Between 2004 and 2016, 34 patients (median age, 57 years; 30 women) with rheumatic disease underwent pannus removal on the ventricular side of a mechanical mitral valve through the aortic valve during reoperation. The median time interval from the previous surgery was 14 years. TMPR was performed after removal of the mechanical aortic valve (n=21) or diseased native aortic valve (n=11). TMPR was performed in 2 patients through a normal aortic valve. The mitral transprosthetic mean pressure gradient (TMPG) was ≥5 mmHg in 11 patients, including 3 with prosthetic valve malfunction. Prophylactic TMPR was performed in 23 patients. There were no early deaths. Concomitant operations included 22 tricuspid valve surgeries (13 replacements, 15 repairs) and 32 aortic valve replacements (24 repeats, 8 primary). The mean gradient in patients who had mitral TMPG ≥5 mmHg was significantly decreased from 6.46±1.1 to 4.37±1.17 mmHg at discharge (P<0.001). No mechanical valve malfunction was apparent on last echocardiography. TMPR is a safe and effective procedure for patients with malfunction or stenosis of a mechanical mitral valve and may be considered an alternative approach in patients with pannus overgrowth in such valves.

An In Vitro Model of Aortic Stenosis for the Assessment of Transcatheter Aortic Valve Implantation

A significant number of elderly patients with severe symptomatic aortic stenosis are denied surgical aortic valve replacement (SAVR) because of high operative risk. Transcatheter aortic valve implantation (TAVI) has emerged as a valid alternative to SAVR in these patients. One of the main characteristics of TAVI, when compared to SAVR, is that the diseased native aortic valve remains in place. For hemodynamic testing of new percutaneous valves and clinical training, one should rely on animal models. However, the development of an appropriate animal model of severe aortic stenosis is not straightforward. This work aims at developing and testing an elastic model of the ascending aorta including a severe aortic stenosis. The physical model was built based on a previous silicone model and tested experimentally in this study. Experimental results showed that the error between the computer-aided design (CAD) file and the physical elastic model was &lt;5%, the compliance of the ascending aorta was 1.15 ml/mm Hg, the effective orifice area (EOA) of the stenotic valve was 0.86 cm2, the peak jet velocity was 4.9 m/s and mean transvalvular pressure gradient was 50 mm Hg, consistent with as severe. An EDWARDS-SAPIEN 26 mm valve was then implanted in the model leading to a significant increase in EOA (2.22 cm2) and a significant decrease in both peak jet velocity (1.29 m/s) and mean transvalvular pressure gradient (3.1 mm Hg). This model can be useful for preliminary in vitro testing of percutaneous valves before more extensive animal and in vivo tests.

Transcatheter aortic valve replacement in elderly patients

Aortic stenosis is the most common native valve disease, affecting up to 5% of the elderly population. Surgical aortic valve replacement reduces symptoms and improves survival, and is the definitive therapy in patients with symptomatic severe aortic stenosis. However, despite the good results of classic surgery, risk is markedly increased in elderly patients with co-morbidities. Transcatheter aortic valve replacement (TAVR) allows implantation of a prosthetic heart valve within the diseased native aortic valve without the need for open heart surgery and cardiopulmonary bypass, offering a new therapeutic option to elderly patients considered at high surgical risk or with contraindications to surgery. To date, several multicenter registries and a randomized trial have confirmed the safety and efficacy of TAVR in those patients. In this chapter, we review the background and clinical applications of TAVR in elderly patients.

Robot-Assisted Aortic Valve Replacement Using a Novel Sutureless Bovine Pericardial Prosthesis Proof of Concept as an Alternative to Percutaneous Implantation

: Percutaneous aortic valve implantation within native valve calcium has progressed to clinical use despite the absence of data proving equivalence to complete surgical excision and prosthetic valve replacement. A novel self-expanding sutureless bovine pericardial prosthesis (Sorin Perceval) derived from a proven stented valve has been successfully used in humans recently through an open transaortic approach. We sought to develop a minimally invasive technique for native aortic valve excision and sutureless prosthetic aortic valve replacement using robot assistance. : The da Vinci S-HD system was used to open and suspend the pericardium anterior to the phrenic nerve in cadavers. A transthoracic cross-clamp was placed across the midascending aorta, following which a transverse aortotomy was made. The native aortic valve cusps were excised, and annular calcium was removed with robotic instruments. After placement of three guide sutures, the Perceval self-expanding pericardial prosthesis mounted on a flexible delivery system was inserted through a working port and lowered into the aortic annulus. : Successful implantation of all valves was possible using a 3-cm right second intercostal space working port, along with two additional 1-cm instrument ports. A standard transverse aortotomy was sufficient for examination/debridement of the native aortic valve cusps, sizing of the annulus, and deployment of the nitinol-stented, bovine pericardial prosthesis. Delivery, seating, and stability of the device were easily confirmed above and below the aortic valve annulus using the robotic camera. : Complete excision of diseased native aortic valve cusps with robot assistance facilitates accurate and reproducible aortic valve replacement using a novel self-expanding sutureless version of a proven bovine pericardial prosthesis. This approach is comparable to the current surgical gold standard and is ready for clinical use as an alternative to percutaneous aortic valve implantation.

Robot-assisted aortic valve replacement using a novel sutureless bovine pericardial prosthesis: proof of concept as an alternative to percutaneous implantation.

: Percutaneous aortic valve implantation within native valve calcium has progressed to clinical use despite the absence of data proving equivalence to complete surgical excision and prosthetic valve replacement. A novel self-expanding sutureless bovine pericardial prosthesis (Sorin Perceval) derived from a proven stented valve has been successfully used in humans recently through an open transaortic approach. We sought to develop a minimally invasive technique for native aortic valve excision and sutureless prosthetic aortic valve replacement using robot assistance. : The da Vinci S-HD system was used to open and suspend the pericardium anterior to the phrenic nerve in cadavers. A transthoracic cross-clamp was placed across the midascending aorta, following which a transverse aortotomy was made. The native aortic valve cusps were excised, and annular calcium was removed with robotic instruments. After placement of three guide sutures, the Perceval self-expanding pericardial prosthesis mounted on a flexible delivery system was inserted through a working port and lowered into the aortic annulus. : Successful implantation of all valves was possible using a 3-cm right second intercostal space working port, along with two additional 1-cm instrument ports. A standard transverse aortotomy was sufficient for examination/debridement of the native aortic valve cusps, sizing of the annulus, and deployment of the nitinol-stented, bovine pericardial prosthesis. Delivery, seating, and stability of the device were easily confirmed above and below the aortic valve annulus using the robotic camera. : Complete excision of diseased native aortic valve cusps with robot assistance facilitates accurate and reproducible aortic valve replacement using a novel self-expanding sutureless version of a proven bovine pericardial prosthesis. This approach is comparable to the current surgical gold standard and is ready for clinical use as an alternative to percutaneous aortic valve implantation.

Technique of Transcatheter Aortic Valve Implantation with the Edwards-Sapien® Heart Valve Using the Transfemoral Approach

Transcatheter aortic valve implantation (TAVI) using a balloon-expandable valve has been developed by the authors' group 7 years ago to offer a therapeutic solution to nonoperable or surgical high-risk patients with degenerative aortic stenosis. The technique and the devices used have rapidly evolved thereafter and TAVI has become a clinical reality with more than 3,500 patients implanted worldwide with this device. The currently used Edwards-Sapien Transcatheter Heart Valve (THV) consists of a balloon-expandable stent with an integrated bovine pericardial valve. It can be implanted within the diseased native aortic valve using either the retrograde transfemoral or antegrade transapical routes. This article is aimed at describing the updated transfemoral technique. Appropriate patient selection is crucial for a successful procedure including close evaluation of the arterial characteristics. After predilatation of the native valve with a balloon catheter, the THV with its delivery system is introduced within the femoral artery, advanced to the native aortic valve under X-ray control, positioned across the aortic annulus, and delivered by balloon inflation under rapid heart pacing. The acute procedural success is 96% and the technique leads to an immediate and lasting improvement of hemodynamics and clinical status. Complications are rare and the mortality rate is 6.3% at 1 month in this cohort of very sick patients. Procedural complications are headed by vascular injury related to the large size of the arterial introducers. An upcoming lower- profile Edwards THV should improve this issue and increase the indication for this less invasive approach in the near future. At the present time, the indications should be restricted to nonoperable or surgical high-risk patients and the procedure performed by experienced and formally trained physicians working in an optimal multidisciplinary environment.

Human Minimally Invasive Off-Pump Valve-in-a-Valve Implantation

Reoperative heart valve replacement for degenerated xenografts is associated with an increased surgical risk. We used our experience with transcatheter transapical aortic valve implantation to perform a transapical off-pump aortic valve-in-a-valve implantation. Hemodynamic function was excellent and the patient had a fast and uneventful recovery.

Prospects for Percutaneous Valve Therapies

Developmental efforts to achieve percutaneous catheter-based therapies for cardiac valve repair and replacement have advanced rapidly over the past several years. A variety of methods to treat mitral regurgitation (MR) and to replace aortic and pulmonic valves have already been successfully employed in patients. These innovative clinical transcatheter valve therapies were anticipated more than a decade ago by creative experimentalists who helped develop predicate techniques in animal models. For example, in 1992, a catheter-delivered ball-in-cage prosthetic aortic valve was implanted in a canine model by Pavcnik1 and a stent-mounted bioprosthetic valve was placed by Andersen, who used a retrograde transarterial approach in a swine model.2 Clearly, the catheter-based technologies used in clinical studies today in patients with aortic stenosis were derived from the fusion of known successful aortic valve replacement (AVR) surgical devices and adaptive interventional modalities, first studied in experimental animal models. Similarly, approaches for transcatheter treatment of MR have also borrowed heavily from preexisting and accepted surgical techniques, such as the edge-to-edge leaflet coaptation technique and reduction ring mitral annuloplasty.3 Importantly, recognition that the coronary sinus parallels the mitral annulus has spurred unique catheter-based transvenous approaches to treat MR by indirectly reducing mitral annular dimensions.4 Because many of the new percutaneous approaches to valve therapy have been developed by surgeons, a collaboration has emerged between thoughtful surgeons and interventionalists, combining skill sets and experiences to accelerate the developmental pathways of less-invasive transcatheter valve therapies. Growing recognition exists that percutaneous alternatives to surgical therapies are required in some patient subgroups with valvular heart disease. Among patients with either mitral and/or aortic valve disease, an expanding population of elderly patients with significant comorbidities may benefit from traditional surgical methods, but these methods are associated with unacceptable perioperative mortality or prolonged postoperative recoveries. In the EuroHeart Survey …

Three-dimensional in vivo characterization of calcification in native valves and in Freestyle versus homograft aortic valves

This article describes a novel interactive method for quantitative evaluation of calcium deposits in the aortic valve by means of electron beam tomography data fusion technique. The technique relied on the use of hierarchic 3-dimensional free-form volume registration with fast global optimization between normally acquired and contrast-enhanced electron beam tomographic volume. A total of 66 contrast-enhanced electron beam tomographic scans of the aortic root were performed in 27 patients, 10 with native aortic valve disease (group A) and 17 from a prospective randomized trial of aortic root replacement (group B, 9 Freestyle grafts [Medtronic, Inc, Minneapolis, Minn] and 8 homografts). To validate the in vivo electron beam tomographic measurements, 5 patients from group A underwent electron beam tomographic scans before the operation and then had their own valves, explanted at the time of surgery, analyzed for calcium quantification by ex vivo electron beam tomography. In group A, the mean (+/- SE) calcification score was 6560 +/- 2388, which correlated with peak gradients measured at echocardiography ( r = 0.93, P = .02). In group B, the mean (+/- SE) calcification score was 168 +/- 27, showing a tendency toward a lower calcification for Freestyle valves than for homografts at 2 years after implantation ( P = .052). A mean variability of 6% was found between in vivo electron beam tomographic scores of calcification and those measured on valve specimens after explantation. We describe a novel method to characterize the degree and location of calcification in both native valves and postoperative valve implants. The technique may be useful in the management of patients with aortic valve disease and has potential as a screening tool for high-risk patients to diagnose early valve calcification and possibly institute corrective measures.

Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis

Background— The design of a percutaneous implantable prosthetic heart valve has become an important area for investigation. A percutaneously implanted heart valve (PHV) composed of 3 bovine pericardial leaflets mounted within a balloon-expandable stent was developed. After ex vivo testing and animal implantation studies, the first human implantation was performed in a 57-year-old man with calcific aortic stenosis, cardiogenic shock, subacute leg ischemia, and other associated noncardiac diseases. Valve replacement had been declined for this patient, and balloon valvuloplasty had been performed with nonsustained results. Methods and Results— With the use of an antegrade transseptal approach, the PHV was successfully implanted within the diseased native aortic valve, with accurate and stable PHV positioning, no impairment of the coronary artery blood flow or of the mitral valve function, and a mild paravalvular aortic regurgitation. Immediately and at 48 hours after implantation, valve function was excellen...

Medium-term determinants of left ventricular mass index after stentless aortic valve replacement

Background. This study aimed to investigate the risk factors for elevated left ventricular mass index 3 to 5 years after stentless aortic valve replacement, and to elucidate the underlying physiologic mechanisms. Methods. Eighty-nine patients (age, 76 ± 6 years, 51 males) having a stentless porcine valve for aortic stenosis (n = 76) or regurgitation (n = 13) were prospectively studied by Doppler echocardiography 3 to 5 years after operation. Left ventricular systolic function, mass index, blood pressure, cardiac rhythm, and New York Heart Association function class were all determined. Stentless valve effective orifice area, mean pressure drop, and the presence and degree of aortic regurgitation were quantified. Results. The mean stentless aortic valve size was 24 ± 2 mm. At follow-up time of 45 ± 9 months, effective orifice area index was 1.2 ± 0.35 cm 2 · m −2, and mean pressure drop was 5.7 ± 3.8 mm Hg. Left ventricular mass index was 128 ± 47 g · m −2, and ejection fraction was 63% ± 14%. Multivariant analysis showed a greater left ventricular mass index to be associated with nonsinus rhythm (versus sinus) (163 ± 8 versus 131 ± 7 g · m −2), greater pulse pressure (> 84 mm Hg) (161 ± 7 versus 133 ± 7 g · m −2), New York Heart Association class II or III (versus class I) (166 ± 10 versus 128 ± 5 g · m −2), and male sex (versus female) (160 ± 7 versus 134 ± 8 g · m −2), all p < 0.01. Mean pressure drop (> 8 mm Hg), effective orifice area index (< 1.0 cm 2 · m −2), the presence of mild regurgitation of the stentless valve, or the type of previous valve disease were insignificant determinants of left ventricular mass index. Conclusions. Three to five years after the implantation, stentless aortic valve hemodynamics remain excellent. Left ventricular hypertrophy caused by previous native aortic valve disease had largely regressed. However, patient-related factors, particularly systemic blood pressure, cardiac rhythm, and function, are significant causes of late residual left ventricular hypertrophy. Thus, continued medical care and earlier surgical intervention may further improve the outlook for these patients.

Transesophageal echocardiography in the evaluation of prosthetic and native aortic valves

Transesophageal echocardiography (TEE) has gained relatively slow acceptance in North America despite its widespread popularity in Europe and Japan. 1,2 Through this new acoustic window high-quality images of certain posteriorly located cardiovascular structures such as the interatrial septum, the left atrial appendage and the thoracic aorta, which often prove difficult to evaluate in detail from the precordium, can be readily obtained. The improved miniaturization and sophistication of esophageal transducers, which incorporate simultaneous Doppler and color flow imaging, has precipitated application of the technique both in the intraoperative and outpatient setting. Transesophageal studies of dysfunctional native mitral valves have been found extremely helpful in defining the cause and quantifying the degree of regurgitation. 3 The advantage of TEE in assessing prosthetic mitral valves is even greater because the prosthetic material, which frequently attenuates the signal and masks the presence and extent of a regurgitant jet on surface echocardiography (echo), 4 is no longer a problem. The same advantage of TEE over surface echo has been described to a limited extent in native aortic valve disease, 5,6 but this has not been demonstrated in patients with prosthetic valves in whom signal quality from within the prosthesis is said to be poor and visualization of the leaflets incomplete. 7 These factors prompted us to review our initial experience with TEE in evaluating aortic valve dysfunction in both native and prosthetic valves.