Jane Hancock

Effects of aging on left atrial reservoir, conduit, and booster pump function: a multi-institution acoustic quantification study

OBJECTIVE To assess the feasibility of measuring left atrial (LA) function with acoustic quantification (AQ) and then assess the effects of age and sex on LA reservoir, conduit, and booster pump function. PATIENTS AND SETTING 165 subjects without cardiovascular disease, 3–79 years old, were enrolled by six tertiary hospital centres. INTERVENTIONS Continuous LA AQ area data were acquired and signal averaged to form composite waveforms which were analysed off-line. MAIN OUTCOME MEASURES Parameters of LA performance according to age and sex. RESULTS Signal averaged LA waveforms were sufficiently stable and detailed to allow automated analysis in all cases. An age related increase in LA area was noted. LA reservoir function did not vary with age or sex. All parameters of LA passive and active emptying revealed a significant age dependency. Overall, the passive emptying phase accounted for 66% of total LA emptying ranging from 76% in the youngest to 44% in the oldest decade. LA contraction accounted for 34% of atrial emptying in all subjects combined with the older subjects being more dependent on atrial booster pump function. When adjusted for atrial size, there were no sex related differences in LA function. CONCLUSIONS LA reservoir, conduit, and booster pump function can be assessed with automated analysis of signal averaged LA area waveforms. As LA performance varies with age, establishment of normal values should enhance the evaluation of pathologic states in which LA function is important.

Registration of 3D trans-esophageal echocardiography to x-ray fluoroscopy using image-based probe tracking

Two-dimensional (2D) X-ray imaging is the dominant imaging modality for cardiac interventions. However, the use of X-ray fluoroscopy alone is inadequate for the guidance of procedures that require soft-tissue information, for example, the treatment of structural heart disease. The recent availability of three-dimensional (3D) trans-esophageal echocardiography (TEE) provides cardiologists with real-time 3D imaging of cardiac anatomy. Increasingly X-ray imaging is now supported by using intra-procedure 3D TEE imaging. We hypothesize that the real-time co-registration and visualization of 3D TEE and X-ray fluoroscopy data will provide a powerful guidance tool for cardiologists. In this paper, we propose a novel, robust and efficient method for performing this registration. The major advantage of our method is that it does not rely on any additional tracking hardware and therefore can be deployed straightforwardly into any interventional laboratory. Our method consists of an image-based TEE probe localization algorithm and a calibration procedure. While the calibration needs to be done only once, the GPU-accelerated registration takes approximately from 2 to 15s to complete depending on the number of X-ray images used in the registration and the image resolution. The accuracy of our method was assessed using a realistic heart phantom. The target registration error (TRE) for the heart phantom was less than 2mm. In addition, we assess the accuracy and the clinical feasibility of our method using five patient datasets, two of which were acquired from cardiac electrophysiology procedures and three from trans-catheter aortic valve implantation procedures. The registration results showed our technique had mean registration errors of 1.5-4.2mm and 95% capture range of 8.7-11.4mm in terms of TRE.

Real-Time Three-Dimensional Transesophageal Echocardiography Adds Value to Transcatheter Aortic Valve Implantation

BACKGROUND Successful transcatheter aortic valve implantation (TAVI) mandates comprehensive, accurate multimodality imaging. Echocardiography is involved at all key stages and, with the advent of real-time three-dimensional (3D) transesophageal echocardiography, is uniquely placed to enable periprocedural monitoring. The investigators describe a comprehensive two-dimensional (2D) and 3D echocardiographic protocol, and the additional benefits of 3D TEE, within a high-volume TAVI program. METHODS TAVI was performed with 2D and 3D transesophageal echocardiographic and fluoroscopic guidance in consecutive high-risk patients with symptomatic severe aortic stenosis. The role of TEE, including the additive value of 3D TEE, was examined, and procedural and echocardiographic outcomes were evaluated. A 3D sizing transcatheter heart valve (THV) strategy was used, except as mandated by study protocol. RESULTS Procedural success was achieved in 99% of 256 patients (mean age, 82.9 ± 7.1 years, mean logistic European System for Cardiac Operative Risk Evaluation score, 21.6 ± 11.2%; mean aortic valve area, 0.63 ± 0.19 cm(2)), with no procedural deaths. Acceptable 2D and 3D transesophageal echocardiographic images were achieved in all patients. Aortic valve annular dimensions by 2D transthoracic echocardiography, 2D TEE, and 3D TEE were 21.6 ± 1.9 mm, 22.5 ± 2.2 mm (P < .001), and 23.0 ± 2.0 mm (P = .004 vs 2D TEE), respectively. The 2D THV sizing strategy would have changed THV selection in 23% of patients, downsizing in most. Three-dimensional TEE provided superior spatial visualization and anatomic orientation and optimized procedural performance. Postprocedural mild, moderate, and severe paravalvular aortic regurgitation was observed in 24%, 3%, and 0% of patients, respectively, with no or trace transvalvular aortic regurgitation in 95%. A second valve was successfully deployed in five patients, and TEE detected five other periprocedural complications. CONCLUSIONS A systematic, comprehensive echocardiographic protocol, incorporating the additional benefits of 3D TEE, has a vital role within a TAVI program and, combined with a 3D THV sizing strategy, contributes to excellent outcomes.

Use of transcatheter heart valves for a valve-in-valve implantation in patients with degenerated aortic bioprosthesis: Technical considerations and results

OBJECTIVE Transcatheter aortic valve implantation has been used to treat high-risk patients with bioprosthetic valve degeneration (valve-in-valve). We report our experience with transcatheter aortic valve implantation in the treatment of degenerated biologic aortic valve prostheses and discuss factors that can influence the outcome. METHODS From February 2009 to October 2011, 278 patients underwent transcatheter aortic valve implantation, of whom 23 underwent a valve-in-valve procedure with the Edwards Sapien valve to treat a failing bioprostheses in the aortic position. Eight of these valves were stentless bioprostheses. Thirteen patients had valve failure resulting predominantly from stenosis, and the remaining resulting from regurgitation. RESULTS Mean age was 76.9 ± 14.4 years. The mean logistic EuroSCORE was 31.8% ± 20.3% and the Society of Thoracic Surgeons score was 7.6% ± 5.4%. All patients were New York Heart Association class III or IV. The majority of the operations (21/23) were performed via the transapical route. Procedural success was 100%, although 1 patient with a degenerated homograft needed immediate placement of a second valve because of low placement of the first. The reduction in the mean gradient was 31.2 ± 17.06 mm Hg to 9.13 ± 4.9 mm Hg. In those patients with predominant aortic regurgitation (9/23), reduction in aortic regurgitation was achieved in all. The median length of stay was 11.7 days (range, 3-44 days). In-hospital and/or 30-day mortality was 0%. CONCLUSIONS Valve-in-valve is a safe and feasible alternative to treat high-risk patients with failing aortic bioprostheses. The early results are excellent, with improvement seen in hemodynamics.

First successful trans-catheter aortic valve implantation through ascending aorta using Edwards SAPIEN THV system

Trans-catheter aortic valve implantation is rapidly becoming an established modality of treatment for patients with critical aortic stenosis who are high risk for conventional aortic valve replacement. This approach also has its limitations; however, with growing experience and improvements in the delivery system, it may be possible to overcome these limitations. We describe a case where conventional trans-catheter approaches, that is, transfemoral or trans-apical using the Edwards THV system, were not possible but successful implantation was achieved through the trans-aortic route.

Transcatheter mitral valve implantation (TMVI) using the Edwards FORTIS device.

Transcatheter aortic valve implantation (TAVI) has demonstrated the feasibility of treating valvular heart disease with transcatheter therapy. On the back of this success, various transcatheter concepts are being evaluated to treat other valvular disease, especially mitral regurgitation (MR). The concepts currently approved to treat MR replicate surgical mitral valve repair. However, most of them cannot eliminate MR completely. Similar to TAVI, a transcatheter mitral valve implantation may provide a valuable alternative. The FORTIS transcatheter mitral valve (Edwards Lifesciences, Irvine, CA, USA) is a self-expanding device implanted via a transapical approach. We describe our experience and early results in the first five patients treated on compassionate grounds. We also describe the details of the device, selection criteria and technical details of implantation.

The effects of VARC-defined acute kidney injury after transcatheter aortic valve implantation (TAVI) using the Edwards bioprosthesis

AIMS The aim of this study was to identify the incidence and risk factors for acute kidney injury (AKI) after TAVI, a potentially serious complication of transcatheter aortic valve implantation (TAVI) that has been redefined by the Valve Academic Research Consortium (VARC). METHODS AND RESULTS We performed a retrospective analysis of 248 patients undergoing TAVI. AKI was defined as a VARC-modified Risk, Injury, Failure, Loss, and End-stage (RIFLE) kidney disease score ≥ 2. Eighty-nine patients suffered AKI (35.9%) and demonstrated increased mortality at 30 days (13.5% vs. 3.8%) and one year (31.5% vs. 15.0%) (p<0.001). Multivariate regression analysis identified diabetes mellitus (p<0.001), peripheral vascular disease (p=0.007), chronic kidney disease stage (p=0.010) as independently associated risk factors for AKI. CONCLUSIONS More than one third of patients sustain AKI after TAVI using the Edwards bioprosthesis, as defined by the VARC-modified RIFLE score. AKI increased the mortality at both 30 days and at one year. A history of diabetes mellitus, peripheral vascular disease and higher chronic kidney disease stage had the strongest independent associations with post-TAVI AKI.

Transcatheter aortic valve implantation for severe aortic stenosis—a new paradigm for multidisciplinary intervention: A prospective cohort study

BACKGROUND Transcatheter aortic valve implantation (TAVI) is an alternative treatment option for patients with aortic stenosis deemed high risk or unsuitable for aortic valve replacement. The aim of this study was to assess the feasibility of TAVI in elderly patients, the delivery of this technology with a multidisciplinary approach, and the use of traditional surgical scoring systems. METHODS One hundred fifty-one consecutive patients (mean age 82.6 +/- 7.3 years) with severe aortic stenosis underwent TAVI with the Edwards Lifesciences (Irvine, CA) Sapien bioprosthesis using the transapical (n = 84; 56%) or transfemoral (n = 67; 44%) approach from August 2007 to September 2009 at Kings Health Partners, London, United Kingdom. We analyzed procedural outcome, complications, functional status, and midterm outcome of patients. RESULTS The multidisciplinary team comprised interventional cardiologists, cardiothoracic surgeons, imaging specialists, cardiac anesthetists, and specialist nurses. Seventy percent of patients were in New York Heart Association class III/IV, and logistic EuroSCORE was 21.6 +/- 11.9. Procedural success was achieved in 98%. Postoperative complications included stroke (6%), complete atrioventricular block (5.3%), renal failure requiring hemofiltration (9.3%), and vascular injury (8.6%). Overall 30-day mortality was 9.9% (n = 15). The logistic EuroSCORE was a predictor of short-term mortality (logistic regression model, P < .05). Thirty-day mortality post-TAVI for patients with logistic EuroSCORE <20, 20 to 40, and >40 was 5.4%, 13.2%, and 22.2%, respectively. CONCLUSIONS Transcatheter aortic valve implantation is a feasible treatment option in this patient group with promising short/medium-term results. Renal failure is the commonest short-term complication, and the incidence of vascular complications remains high. Risk prediction/case selection remains challenging, and a multidisciplinary team approach appears to be helpful in appropriate patient selection.

Evaluation of myocardial, hepatic, and renal perfusion in a variety of clinical conditions using an intravenous ultrasound contrast agent (Optison) and second harmonic imaging

OBJECTIVE To assess the potential of intravenous Optison, a second generation ultrasound contrast agent, and various ultrasound imaging modes to determine myocardial, kidney, and liver perfusion in normal subjects and patients with left ventricular dysfunction or chronic pulmonary disease together with renal or hepatic dysfunction. METHODS Five normal subjects and 20 patients underwent grey scale echocardiographic imaging of myocardium, kidney, and liver during 505 intravenous injections of Optison. Images were assessed qualitatively by two independent observers and quantitatively using video densitometry to determine the peak contrast enhancement effect. RESULTS Qualitative analysis showed that intermittent harmonic imaging was superior to either conventional fundamental or continuous harmonic imaging for all organs. Quantitative analysis showed that the peak change in echocardiographic intensity v baseline during continuous harmonic imaging was 11 units for myocardium (p < 0.03), 7 units for kidney (NS), and 14 units for liver (p < 0.05). During intermittent harmonic imaging the peak change was significantly greater, being 33 units for myocardium (p < 0.0001), 24 units for kidney (p < 0.0002), and 16 units for liver (p < 0.001). CONCLUSIONS Organ tissue perfusion can be demonstrated following intravenous injection of Optison, particularly when used in combination with intermittent harmonic imaging techniques. This contrast agent is effective in a variety of clinical conditions.

Randomised trial of elective stenting after successful percutaneous transluminal coronary angioplasty of occluded coronary arteries

Background The value of angioplasty in occluded coronary arteries is limited by a restenosis/reocclusion rate of 50–70%. In patients with subtotal occlusion, stent implantation has been shown to reduce clinical and angiographic restenosis. Retrospective observational studies have suggested that stenting could reduce restenosis in total occlusions. The value of sustained coronary patency on global and regional left ventricular function in this clinical setting has not been defined clearly. Objectives To assess the medium term effect of elective intracoronary stent deployment after successful percutaneous transluminal coronary angioplasty (PTCA) of an occluded coronary artery. Methods Sixty patients with a total coronary occlusion successfully treated by PTCA were randomised to receive an intracoronary stent or no stent. Patients underwent clinical and angiographic follow up at six months. Results Thirty patients received a stent (group A) and 30 were treated by angioplasty alone (group B), all with initial success. One patient in group B required repeat angioplasty with stenting at 24 hours and one patient died after 10 days. Angiographic follow up was available for 57 patients. This showed a significantly reduced reocclusion rate in group A compared with group B (7% v 29%, p < 0.01) and a tendency to a reduced restenosis rate (22% v 40%, p = 0.105) in patients with no reocclusion. Left ventricular function, both global and regional, improved in group A. Only the regional left ventricular function in the area supplied by the target coronary artery improved in group B. Recurrence of symptoms and clinical events such as repeat angioplasty, coronary artery bypass grafting, death or myocardial infarction tended to be reduced in group A (4 (13%) v 9 (30%)). Conclusions Intracoronary stent insertion is effective in reducing the rate of reocclusion and shows a trend towards reduced restenosis after opening of a total coronary occlusion by balloon angioplasty. Sustained patency of the target coronary artery is associated with improvement in global and regional left ventricular function.