Heart valve sound of various mechanical composite grafts, and the impact on patients' quality of life

The closing sounds of mechanical heart valves can be disturbing for patients and their closest relatives. Although some investigations into mechanical heart valve sounds have been performed, the particularities of the valve sound when it is attached to a vascular prosthesis to replace the aortic root and the ascending aorta has not been studied to date. The study aim was to compare the closing sounds of three various mechanical composite graft prostheses, and to analyze the impact of such sounds on the patients' quality of life.

Effect of comprehensive cardiac rehabilitation after heart valve surgery (CopenHeartVR): study protocol for a randomised clinical trial

Background Heart valve diseases are common with an estimated prevalence of 2.5% in the Western world. The number is rising due to an ageing population. Once symptomatic, heart valve diseases are potentially lethal, and heavily influence daily living and quality of life. Surgical treatment, either valve replacement or repair, remains the treatment of choice. However, post surgery, the transition to daily living may become a physical, mental and social challenge. We hypothesise that a comprehensive cardiac rehabilitation programme can improve physical capacity and self-assessed mental health and reduce hospitalisation and healthcare costs after heart valve surgery. Methods A randomised clinical trial, CopenHeartVR, aims to investigate whether cardiac rehabilitation in addition to usual care is superior to treatment as usual after heart valve surgery. The trial will randomly allocate 210 patients, 1:1 intervention to control group, using central randomisation, and blinded outcome assessment and statistical analyses. The intervention consists of 12 weeks of physical exercise, and a psycho-educational intervention comprising five consultations. Primary outcome is peak oxygen uptake (VO2 peak) measured by cardiopulmonary exercise testing with ventilatory gas analysis. Secondary outcome is self-assessed mental health measured by the standardised questionnaire Short Form 36. Also, long-term healthcare utilisation and mortality as well as biochemistry, echocardiography and cost-benefit will be assessed. A mixed-method design is used to evaluate qualitative and quantitative findings encompassing a survey-based study before the trial and a qualitative pre- and post-intervention study. Discussion The study is approved by the local regional Research Ethics Committee (H-1-2011-157), and the Danish Data Protection Agency (j.nr. 2007-58-0015).

European experience with the second-generation Edwards SAPIEN XT transcatheter heart valve in patients with severe aortic stenosis: 1-year outcomes from the SOURCE XT Registry

OBJECTIVES The SOURCE XT Registry (Edwards SAPIEN XT Aortic Bioprosthesis Multi-Region Outcome Registry) assessed the use and clinical outcomes with the SAPIEN XT (Edwards Lifesciences, Irvine, California) valve in the real-world setting. BACKGROUND Transcatheter aortic valve replacement is an established treatment for high-risk/inoperable patients with severe aortic stenosis. The SAPIEN XT is a balloon-expandable valve with enhanced features allowing delivery via a lower profile sheath. METHODS The SOURCE XT Registry is a prospective, multicenter, post-approval study. Data from 2,688 patients at 99 sites were analyzed. The main outcome measures were all-cause mortality, stroke, major vascular complications, bleeding, and pacemaker implantations at 30-days and 1 year post-procedure. RESULTS The mean age was 81.4 ± 6.6 years, 42.3% were male, and the mean logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 20.4 ± 12.4%. Patients had a high burden of coronary disease (44.2%), diabetes (29.4%), renal insufficiency (28.9%), atrial fibrillation (25.6%), and peripheral vascular disease (21.2%). Survival was 93.7% at 30 days and 80.6% at 1 year. At 30-day follow-up, the stroke rate was 3.6%, the rate of major vascular complications was 6.5%, the rate of life-threatening bleeding was 5.5%, the rate of new pacemakers was 9.5%, and the rate of moderate/severe paravalvular leak was 5.5%. Multivariable analysis identified nontransfemoral approach (hazard ratio [HR]: 1.84; p < 0.0001), renal insufficiency (HR: 1.53; p < 0.0001), liver disease (HR: 1.67; p = 0.0453), moderate/severe tricuspid regurgitation (HR: 1.47; p = 0.0019), porcelain aorta (HR: 1.47; p = 0.0352), and atrial fibrillation (HR: 1.41; p = 0.0014), with the highest HRs for 1-year mortality. Major vascular complications and major/life-threatening bleeding were the most frequently seen complications associated with a significant increase in 1-year mortality. CONCLUSIONS The SOURCE XT Registry demonstrated appropriate use of the SAPIEN XT THV in the first year post-commercialization in Europe. The safety profile is sustained, and clinical benefits have been established in the real-world setting. (SOURCE XT Registry; NCT01238497).

Tomographic PIV behind a prosthetic heart valve

The instantaneous three-dimensional velocity field past a bioprosthetic heart valve was measured using tomographic particle image velocimetry (PIV). Two digital cameras were used together with a mirror setup to record PIV images from four different angles. Measurements were conducted in a transparent silicone phantom with a simplified geometry of the aortic root. The refraction indices of the silicone phantom and the working fluid were matched to minimize optical distortion from the flow field to the cameras. The silicone phantom of the aorta was integrated in a flow loop driven by a piston pump. Measurements were conducted for steady and pulsatile flow conditions. Results of the instantaneous, ensemble and phase averaged flow field are presented. The three-dimensional velocity field reveals a flow topology, which can be related to features of the aortic valve prosthesis.

Time-Resolved Micro PIV in the Pivoting Area of the Triflo Mechanical Heart Valve

The Lapeyre-Triflo FURTIVA valve aims at combining the favorable hemodynamics of bioprosthetic heart valves with the durability of mechanical heart valves (MHVs). The pivoting region of MHVs is hemodynamically of special interest as it may be a region of high shear stresses, combined with areas of flow stagnation. Here, platelets can be activated and may form a thrombus which in the most severe case can compromise leaflet mobility. In this study we set up an experiment to replicate the pulsatile flow in the aortic root and to study the flow in the pivoting region under physiological hemodynamic conditions (CO = 4.5 L/min / CO = 3.0 L/min, f = 60 BPM). It was found that the flow velocity in the pivoting region could reach values close to that of the bulk flow during systole. At the onset of diastole the three valve leaflets closed in a very synchronous manner within an average closing time of 55 ms which is much slower than what has been measured for traditional bileaflet MHVs. Hot spots for elevated viscous shear stresses were found at the flanges of the housing and the tips of the leaflet ears. Systolic VSS was maximal during mid-systole and reached levels of up to 40 Pa.

Transapical implantation of a novel self-expanding sutureless aortic valve prosthesis

To date, transapical aortic valve implantation has required a balloon-expandable stented valve prosthesis. More recently, a novel self-expanding sutureless stented bovine pericardial prosthesis has been developed which allows rapid aortic valve replacement via an open transaortic approach in humans. The aim of this animal study was to develop a reliable protocol to facilitate the transapical implantation of this self-expanding valve in a porcine model.

Transapical valve-in-valve implantation for regurgitant stented aortic bioprostheses

Transcatheter aortic valve implantation (TAVI) is rapidly evolving as an alternative treatment option for elderly patients with severe symptomatic aortic stenosis and excessive risk for surgical intervention. Transcatheter valve-in-valve implantation is an alternative approach to redo-surgery for patients with degeneration of a bioprosthetic valve. Herein are reported three cases of successful transcatheter aortic valve-in-valve implantation for severely regurgitant bioprosthetic valves with a clinical follow up of more than 12 months.

Transcatheter aortic valve implantation: the procedure

Transcatheter aortic valve implantation (TAVI) for the treatment of symptomatic severe aortic stenosis has emerged as an effective treatment for high risk patients. In 2002 TAVI was performed for the first time in a human by Alain Cribier, using an antegrade access approach via the femoral vein, crossing the intra-atrial septum after puncture and passing the native aortic valve in the direction of blood flow. This technically demanding approach was subsequently replaced by retrograde transfemoral arterial access. For patients with severe peripheral vascular disease or inadequately sized femoral arteries, the transapical route provides an alternative route with antegrade access to the aortic valve via puncture of the anterolateral wall of the left ventricle. The transsubclavian access approach using most frequently the left subclavian artery and direct transaortic access have been introduced more recently and attest to the versatility of TAVI in terms of access site. This article will focus on the different access site options available to operators, provide a step-by-step guide through the procedure, and a detailed description of the technological evolution of transcatheter heart valve systems.

Resuspension of the aortic valve in acute type A dissection: long-term results

BACKGROUND AND AIM OF THE STUDY: Preservation of the aortic valve during the repair of acute type A aortic dissection (AADA) is a viable option to prevent lifelong oral anticoagulation. The study aim was to assess aortic valve function following resuspension and supracoronary ascending aortic grafting. METHODS: Among a collective of 210 consecutive patients undergoing surgery for AADA, 140 (66.7%) with resuspension of the aortic valve and supracoronary ascending graft were analyzed. Of these patients, 83 (59.3%) had a complete follow up (mean 61.2 +/- 40.8 months), with 65 of the subgroup (78.3%) being followed by computed tomography scanning and echocardiography. RESULTS: Reoperation due to severe aortic valve regurgitation was required in seven patients (10.8%). The perioperative characteristics were similar in these patients; notably, no significant difference was evident with regards to the aortic annulus diameter and the severity of regurgitation at the time of surgery. The left ventricular mass index was significantly higher in patients requiring reoperation due to aortic valve regurgitation (219.3 +/- 146.6 versus 123.9 +/- 146.6 g/m2; p <0.05). None of the patients died as a result of reoperation. CONCLUSION: The long-term functional results following resuspension of the aortic valve in AADA were very good. A close echocardiographic follow up was necessary, as reoperation of the aortic valve was required in more than 10% of the collective, with an average follow up of five years. Reoperation was mainly related to secondary dilatation of the aortic root.

Transcatheter Aortic Valve Replacement in Bicuspid Aortic Valve Disease.

BACKGROUND Limited information exists describing the results of transcatheter aortic valve (TAV) replacement in patients with bicuspid aortic valve (BAV) disease (TAV-in-BAV). OBJECTIVES This study sought to evaluate clinical outcomes of a large cohort of patients undergoing TAV-in-BAV. METHODS We retrospectively collected baseline characteristics, procedural data, and clinical follow-up findings from 12 centers in Europe and Canada that had performed TAV-in-BAV. RESULTS A total of 139 patients underwent TAV-in-BAV with the balloon-expandable transcatheter heart valve (THV) (n = 48) or self-expandable THV (n = 91) systems. Patient mean age and Society of Thoracic Surgeons predicted risk of mortality scores were 78.0 ± 8.9 years and 4.9 ± 3.4%, respectively. BAV stenosis occurred in 65.5%, regurgitation in 0.7%, and mixed disease in 33.8% of patients. Incidence of type 0 BAV was 26.7%; type 1 BAV was 68.3%; and type 2 BAV was 5.0%. Multislice computed tomography (MSCT)-based TAV sizing was used in 63.5% of patients (77.1% balloon-expandable THV vs. 56.0% self-expandable THV, p = 0.02). Procedural mortality was 3.6%, with TAV embolization in 2.2% and conversion to surgery in 2.2%. The mean aortic gradient decreased from 48.7 ± 16.5 mm Hg to 11.4 ± 9.9 mm Hg (p < 0.0001). Post-implantation aortic regurgitation (AR) grade ≥2 occurred in 28.4% (19.6% balloon-expandable THV vs. 32.2% self-expandable THV, p = 0.11) but was prevalent in only 17.4% when MSCT-based TAV sizing was performed (16.7% balloon-expandable THV vs. 17.6% self-expandable THV, p = 0.99). MSCT sizing was associated with reduced AR on multivariate analysis (odds ratio [OR]: 0.19, 95% confidence intervals [CI]: 0.08 to 0.45; p < 0.0001). Thirty-day device safety, success, and efficacy were noted in 79.1%, 89.9%, and 84.9% of patients, respectively. One-year mortality was 17.5%. Major vascular complications were associated with increased 1-year mortality (OR: 5.66, 95% CI: 1.21 to 26.43; p = 0.03). CONCLUSIONS TAV-in-BAV is feasible with encouraging short- and intermediate-term clinical outcomes. Importantly, a high incidence of post-implantation AR is observed, which appears to be mitigated by MSCT-based TAV sizing. Given the suboptimal echocardiographic results, further study is required to evaluate long-term efficacy.

Expanding Indications of Transcatheter Heart Valve Interventions.

Transcatheter aortic valve replacement (TAVR) has been established as a less invasive alternative to open-heart surgery in inoperable or high-risk patients presenting with symptomatic severe aortic valve stenosis. The feasibility and efficacy of valve-in-valve implantation in degenerated surgical aortic bioprostheses have also been described and can currently be considered a valuable treatment option in patients deemed unsuitable for repeat cardiac surgery. However, the clinical use of TAVR devices is not limited to the treatment of the tricuspid stenotic aortic valve. Several additional indications including treatment of the bicuspid stenotic aortic valve, aortic regurgitation, and valve-in-valve or valve-in-ring implantation in the mitral or tricuspid position as well as treatment of pure mitral, tricuspid, or pulmonary regurgitation have been described. The purpose of the present review is to summarize the available evidence concerning the emerging off-label use of TAVR devices in current clinical practice. Case examples have been selected to highlight the main procedural steps of each particular intervention.

[Neuromonitoring and neuroprotection in cardiac anaesthesia. Nationwide survey conducted by the Cardiac Anaesthesia Working Group of the German Society of Anaesthesiology and Intensive Care Medicine]

OBJECTIVE: The primary objective of this nationwide survey carried out in department of cardiac anesthesia in Germany was to identify current practice with regard to neuromonitoring und neuroprotection. METHODOLOGY: The data are based on a questionnaire sent out to all departments of cardiac anesthesia in Germany between October 2007 und January 2008. The anonymized questionnaire contained 26 questions about the practice of preoperative evaluation of cerebral vessels, intra-operative use of neuromonitoring, the nature und application of cerebral protective measures, perfusion management during cardiopulmonary bypass, postoperative evaluation of neurological status, and training in the field of cerebral monitoring. RESULTS: Of the 80 mailed questionnaires 55% were returned and 90% of department evaluated cerebral vessels preoperatively with duplex ultrasound. The methods used for intra-operative neuromonitoring are electroencephalography (EEG, 60%) for type A dissections (38.1%), for elective surgery on the thoracic and thoraco-abdominal aorta (34.1% and 31.6%, respectively) and in carotid surgery (43.2%) near infrared spectroscopy (40%), evoked potentials (30%) and transcranial Doppler sonography (17.5%), with some centers using combined methods. In most departments the central nervous system is not subjected to monitoring during bypass surgery, heart valve surgery, or minimally invasive surgery. Cerebral protective measures used comprise patient cooling on cardio-pulmonary bypass (CPB 100%), extracorporeal cooling of the head (65%) and the administration of corticosteroids (58%), barbiturates (50%) and antiepileptic drugs (10%). Neuroprotective anesthesia consists of administering inhalation anesthetics (32.5%; sevoflurane 76.5%) and intravenous anesthesia (20%; propofol and barbiturates each accounting for 46.2%). Of the departments 72.5% cool patients as a standard procedure for surgery involving cardiovascular arrest and 37.5% during all surgery using CPB. In 84.6% of department CPB flow equals calculated cardiac output (CO) under normothermia, while the desired mean arterial pressure (MAP) varies between 60 and 70 mmHg (43.9%) and between 50 and 60 mmHg (41.5%), respectively. At body temperatures less than 18 degrees C CPB flow is reduced below the calculated CO (70%) while 27% of departments use normothermic flow rates. The preferred MAP under hypothermia is between 50 and 60 mmHg (59%). The results of intra-operative neuromonitoring are documented on the anesthesia record (77%). In 42.5% of the departments postoperative neurological function is estimated by the anesthesiologist. Continuing education sessions pertaining to neuromonitoring are organized on a regular basis in 32.5% of the departments and in 37.5% individual physicians are responsible for their own neuromonitoring education. CONCLUSION: The present survey data indicate that neuromonitoring and neuroprotective therapy during CPB is not standardized in cardiac anesthesiology departments in Germany. The systemic use of available methods to implement multimodal neuromonitoring would be desirable.

The role of the sinuses of Valsalva in aortic root flow dynamics and aortic root surgery: evaluation by magnetic resonance imaging

BACKGROUND AND AIM OF THE STUDY: Combined replacement of the aortic valve and ascending aorta using a composite graft represents the standard treatment for dilated aortic root with concomitant structural damage of the aortic valve, especially when the aortic valve cannot be preserved. Unfortunately, hemodynamic changes associated with prosthetic replacement of the aortic root have not been fully elucidated. The study aim was to compare hemodynamics within the replaced aortic root using either a prosthetic vascular graft with bulges mimicking the sinuses of Valsalva and including a stented pericardial valve, or a straight xenopericardial conduit and a stentless porcine valve. METHODS: Between July 2004 and March 2006, a total of 35 patients (mean age 65.2 years: range: 32-80 years) was enrolled into the present study. Aortic root replacement was performed in nine patients with a Valsalva graft (Gelweave Valsalva; Vascutek, Renfrewshire, UK) including a stented pericardial valve, and in 19 patients with a xenopericardial conduit containing a stentless porcine valve. All patients underwent postoperative magnetic resonance imaging (MRI). A control group of seven patients allowed for comparison with native aortic root hemodynamics. RESULTS: Maximum flow-velocity above the aortic valve as one marker of compliance of the aortic root was slightly higher in patients with a Valsalva graft compared to native aortic roots (1.9 m/s versus 1.3 m/s, p = 0.001), but was significantly lower than in patients with the xenopericardial graft without neo-sinuses (1.3 m/s versus 2.4 m/s, p < 0.001). CONCLUSION: The pre-shaped bulges in the prosthetic Valsalva graft effectively mimic the native sinuses of Valsalva, improve compliance of the aortic root, and result in a more physiologic flow pattern, as demonstrated by postoperative MRI.

Valve-in-valve transcatheter aortic valve implantation for degenerated bioprosthetic heart valves

We sought to analyze outcomes of patients with degenerated surgically implanted bioprosthetic heart valves undergoing valve-in-valve (viv) transcatheter aortic valve implantation (TAVI).