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Aims A living heart valve with regeneration capacity based on autologous cells and minimally invasive implantation technology would represent a substantial improvement upon contemporary heart valve prostheses. This study investigates the feasibility of injectable, marrow stromal cell-based, autologous, living tissue engineered heart valves (TEHV) generated and implanted in a one-step intervention in non-human primates. Methods and results Trileaflet heart valves were fabricated from non-woven biodegradable synthetic composite scaffolds and integrated into self-expanding nitinol stents. During the same intervention autologous bone marrow-derived mononuclear cells were harvested, seeded onto the scaffold matrix, and implanted transapically as pulmonary valve replacements into non-human primates (n = 6). The transapical implantations were successful in all animals and the overall procedure time from cell harvest to TEHV implantation was 118 ± 17 min. In vivo functionality assessed by echocardiography revealed preserved valvular structures and adequate functionality up to 4 weeks post implantation. Substantial cellular remodelling and in-growth into the scaffold materials resulted in layered, endothelialized tissues as visualized by histology and immunohistochemistry. Biomechanical analysis showed non-linear stress-strain curves of the leaflets, indicating replacement of the initial biodegradable matrix by living tissue. Conclusion Here, we provide a novel concept demonstrating that heart valve tissue engineering based on a minimally invasive technique for both cell harvest and valve delivery as a one-step intervention is feasible in non-human primates. This innovative approach may overcome the limitations of contemporary surgical and interventional bioprosthetic heart valve prostheses.

Objective: Diabetic patients often present with diffuse coronary disease than nondiabetic patients posing a greater surgical challenge during off-pump revascularization. In this study, the safety, feasibility, and completeness of revascularization for this subset of patients was assessed. Methods: From 2002 to 2008, 1015 diabetic patients underwent myocardial revascularization. Patients received either off-pump coronary artery bypass (OPCAB; n=540; 53%) or coronary artery bypass grafting (CABG; n=475; 47%). Data collection was performed prospectively and data analysis was done by propensity-score (PS)-adjusted regression analysis. Primary endpoints were mortality, major adverse cardiac and cerebrovascular events (MACCEs), and a composite endpoint including major noncardiac adverse events (MNCAEs) such as respiratory failure, renal failure, and rethoracotomy for bleeding was applied. An index of complete revascularization (ICOR) was defined to assess complete revascularization by dividing the total number of distal anastomoses by the number of diseased vessels. Complete revascularization was assumed when ICOR was >1. Results: OPCAB patients had a significantly lower mortality-rate (1.1% vs 3.8%; propensity-adjusted odds ratio (PAOR)=0.11; p=0.018) and displayed less frequent MACCE (8.3% vs 17.9%; PAOR=0.66; p=0.07) including myocardial infarction (1.3% vs 3.2%; PAOR=0.33; p=0.06) and stroke (0.7% vs 2.3%; PAOR=0.28; p=0.13). Similarly, a significantly lower occurrence of the noncardiac composite endpoint (MNCAE) (PAOR=0.46; confidence interval (CI) 95% 0.35-0.91; p<0.001) was detected. In particular, lesser respiratory failure (0.9% vs 4.3%; PAOR=0.24; p=0.63) and pleural effusions (3.3% vs 7.5%; PAOR=0.45; p=0.04) occurred, so that fast extubation (≤12h postoperative) was more frequently possible (58.3% vs 34.2%; PAOR=1.64; p=0.007). The number of arterial grafts was significantly higher among OPCAB patients (1.54±0.89 vs 1.33±0.81; p=0.006) due to a more frequent u

Lead extraction, a demanding task: Every year approximately 1 0 000–15 000 pacemakerand ICD-leads are extracted worldwide with numbers continuing to rise. The increasing need for lead extractions may be explained by the evolution of pacemakerand ICD-implants during the last decade as well as by the widened spectrum of extraction devices and techniques. Last but not least, in 2009 the indications for transvenous lead extractions were broadened by the Heart Rhythm Society. Lead extraction are not simple operations at all, but instead can be very challenging with a recognisable risk profile. When carried out by specialised centres lead extractions may be performed with high success rates (>95%), and low complication rates (<2%) and mortality (<0.5%).

Transcatheter aortic valve implantation (T-AVI) has shown good results in high-risk patients with severe aortic stenosis. Throughout the whole process of T-AVI, different imaging modalities are indispensable. Preoperatively, multislice computed tomography, angiography and transesophageal echo (TEE) are utilized for patient selection, valve selection, approach selection and the planning of implant placement. Intraoperatively, angiography and TEE are used for controlling placement of the guidewire and valve positioning. Quality control and follow-up require TEE imaging and can require additional CT or angiography studies. In the first half of this paper, we discuss the applicability of different imaging modalities for T-AVI in the light of the current best practice. In the second half of this paper, we present an overview on research projects in medical engineering which aim at development of image-based methods for increasing patient safety during T-AVI. Template-based implantation planning, as it is applied in dental, orthopedic and other surgical disciplines, is proposed as an aid during implant selection in order to help reduce the incidence of complications such as atrioventricular node block and paravalvular leaks. Current research tries to apply state-of-the-art engineering techniques, such as computational fluid dynamics to optimize valve selection and positioning. For intraoperative assistance during valve positioning, real-time image processing methods are proposed to track target landmarks and the stented valve.

We studied the diagnostic accuracy of computed tomography coronary angiography (CTCA) for the diagnosis of significant coronary artery disease (CAD) compared to conventional coronary angiography (CCA) in patients with primary cardiac tumors. Thirty-eight consecutive patients with primary cardiac tumors (27 females, 11 males; mean age 56+/-6 years, range 32-86 years) underwent dual-source CTCA and CCA. Significant stenosis was defined as diameter reduction >50%. CCA served as the standard of reference. The prevalence of significant CAD in the study population was 8% (3/38 patients). Five of 544 segments (0.9%) in 1/38 patients (2.6%) was considered of non-diagnostic image quality on CTCA because of motion artifacts. In a segment-based analysis taking not-evaluative segments as false-positive, sensitivity, specificity, positive and negative predictive value of CT was 100%, 99%, 70%, and 100%, respectively. Preoperative CCA could have been avoided in 95% (36/38) of the patients and CCA would have confirmed the CTCA diagnosis in 5% (2/38) of the patients. Our results indicate that CTCA provides a high diagnostic performance for diagnosing significant CAD in patients with primary cardiac tumors. CTCA may thus be used as a filter test prior to surgery. Keywords: Primary cardiac tumors; Coronary artery disease; Computed tomography; Conventional coronary angiography.

Background: This study assesses the accuracy of the new dual-source computed tomography (DSCT) for detection of coronary artery disease (CAD) compared with invasive coronary angiography (ICA) with a specifically designed data presentation protocol for cardiac surgeons. Methods: Forty patients (30 males/10 females) underwent ICA and DSCT. Best-quality images were prepared by radiologists. Evaluation of 12 segments of significant coronary stenosis was done by two cardiac surgeons with a data presentation protocol including different coronary views in two-/three-dimensional (2D/3D) images. No beta-blockers were administered prior to DSCT. Results: ICA revealed CAD in 21 patients and valvular disease but no CAD in 19 patients. In DSCT, 20/21 patients were diagnosed with CAD (at least one significant stenosis per patient). In 11/21 patients, all 12 segments were assessed correctly; in 7/21 patients one segment and in 3/21 patients two segments were evaluated incorrectly. Of all 21 patients with CAD, 239/252 segments (95%) were correctly evaluated. In 18/19 patients without CAD, DSCT correctly ruled-out the ICA results in 226/228 segments (99%). In total, 465/480 segments were correctly assessed (97%). Of 480 segments, only six were considered not assessable. DSCT assessments of the segments showed a sensitivity of 91%, specificity of 99%, a positive predictive value of 92% and a negative predictive value of 99%. Conclusions: The accuracy of DSCT coronary angiography especially for exclusion of CAD is promising. The introduced data presentation protocol allows for the independent evaluation by cardiac surgeons after pre-arrangement from the radiologists.

INTRODUCTION: Latest techniques enable positioning of devices into the coronary sinus (CS) for mitral valve (MV) annuloplasty. We evaluate the feasibility of non-invasive assessment to determine CS anatomy and its relation to MV annulus and coronary arteries by multi-slice CT (MSCT) in normal and insufficient MV. METHODS: Fifty patients (33 males, 17 females, age 67+/-11 years) were studied retrospectively by 64-MSCT scans for anatomical criteria regarding CS and its relation to MV annulus and circumflex artery (CX). We included 24 patients with severe mitral insufficiency and 26 with no MV disease. Diameter of MV, of proximal and distal ostium of CS, length and volume of CS, angle between anterior interventricular vein (AIV) and CS, caliber change of CX before, under/over and after CS were analysed. Different anatomical correlations were demonstrated: distance of MV annulus to CS, CX to CS. RESULTS: Diameter of proximal CS ostium was significantly larger in insufficient MV compared to normal MV (11+/-2.8 mm vs 9.9+/-2.5 mm; p<0.024). CS was significantly longer in patients with insufficient MV (125.4+/-17 mm vs 108.9+/-18 mm; p<0.003) with also significant differences in volume of CS (p<0.039). Significant difference in annulus diameter, 46.1+/-6mm (insufficient MV) versus 39.5+/-7.5 mm, p<0.004 was observed. Angle CS-AIV was 103.5+/-29 degrees (range 52 degrees -144 degrees ) in insufficient valves versus 118.2+/-24.5 degrees (range 73 degrees -166 degrees ) in normal valves with a tendency to higher angles in normal valves (p=0.06). Distance of MV annulus to CS measured 16+/-4.1/14.2+/-3.6 mm (insufficient/normal MV) without significant difference between groups. In 15 patients CX ran under CS. Eighty-four percent of these patients (13/15) show a decrease in CS caliber in the area of intersection. In 14 patients CS ran over and in one patient the diameter of the CS at intersecting region was smaller. In 16 patients no direct point of contact was visible, in five

In a 13-year-old boy a correction of an atrioventricular septal defect (AVSD) was performed at the age of one year and a mitral valve reconstruction at the age of two years. The patient developed, after two median sternotomies, a massive sternal deformity. At the age of 12 years another mitral valve reconstruction had to be performed. At this time titanium plates were used for sternal closure and correction of the deformity. Six months later, and after a CT-follow-up, the plates could be removed with a very satisfying result. Sternal plate osteosynthesis represents an excellent alternative for the correction of difficult sternal closures and deformities in adults as well as in children.

The aim of this study was to assess the diagnostic accuracy of dual-source computed tomography (DSCT) for evaluation of coronary artery disease (CAD) in a population with extensive coronary calcifications without heart rate control. Thirty patients (24 male, 6 female, mean age 63.1+/-11.3 years) with a high pre-test probability of CAD underwent DSCT coronary angiography and invasive coronary angiography (ICA) within 14+/-9 days. No beta-blockers were administered prior to the scan. Two readers independently assessed image quality of all coronary segments with a diameter > or =1.5 mm using a four-point score (1: excellent to 4: not assessable) and qualitatively assessed significant stenoses as narrowing of the luminal diameter >50%. Causes of false-positive (FP) and false-negative (FN) ratings were assigned to calcifications or motion artifacts. ICA was considered the standard of reference. Mean body mass index was 28.3+/-3.9 kg/m2 (range 22.4-36.3 kg/m2), mean heart rate during CT was 70.3+/-14.2 bpm (range 47-102 bpm), and mean Agatston score was 821+/-904 (range 0-3,110). Image quality was diagnostic (scores 1-3) in 98.6% (414/420) of segments (mean image quality score 1.68+/-0.75); six segments in three patients were considered not assessable (1.4%). DSCT correctly identified 54 of 56 significant coronary stenoses. Severe calcifications accounted for false ratings in nine segments (eight FP/one FN) and motion artifacts in two segments (one FP/one FN). Overall sensitivity, specificity, positive and negative predictive value for evaluating CAD were 96.4, 97.5, 85.7, and 99.4%, respectively. First experience indicates that DSCT coronary angiography provides high diagnostic accuracy for assessment of CAD in a high pre-test probability population with extensive coronary calcifications and without heart rate control.