Recent developments for surgical aortic valve replacement: the concept of sutureless valve technology

Aortic stenosis has become the most frequent type of valvular heart disease in Europe and North America and presents in the large majority of patients as calcified aortic stenosis in adults of advanced age. Surgical aortic valve replacement has been recognized to be the definitive therapy which improves considerably survival for severe aortic stenosis since more than 40 years. In the most recent period, operative mortality of isolated aortic valve replacement for aortic stenosis varies between 1–3% in low-risk patients younger than 70 years and between 4 and 8% in selected older adults. Long-term survival following aortic valve replacement is close to that observed in a control population of similar age. Numerous observational studies have consistently demonstrated that corrective surgery in symptomatic patients is invariably followed by a subjective improvement in quality of life and a substantial increase in survival rates. More recently, transcatheter aortic valve implantation (TAVI) has been demonstrated to be feasible in patients with high surgical risk using either a retrograde transfemoral or transsubclavian approach or an antegrade, transapical access. Reported 30-day mortality ranges between 5 and 15%) and is acceptable when compared to the risk predicted by the logistic EuroSCORE (varying between 20 and 35%) and the STS Score, although the EuroScore has been shown to markedly overestimate the effective operative risk. One major concern remains the high rate of paravalvular regurgitation which is observed in up to 85% of the patients and which requires further follow-up and critical evaluation. In addition, long-term durability of these valves with a focus on the effects of crimping remains to be addressed, although 3-5 year results are promising. Sutureless biological valves were designed to simplify and significantly accelerate the surgical replacement of a diseased valve and allow complete excision of the calcified native valve. Until now, there are 3 different sutureless prostheses that have been approved. The 3f Enable valve from ATS-Medtronic received CE market approval in 2010, the Perceval S from Sorin during Q1 of 2011 and the intuity sutureless prosthesis from Edwards in 2012. All these devices aim to facilitate valve surgery and therefore have the potential to decrease the invasivness and to shorten the conventional procedure without compromise in term of excision of the diseased valve. This review summarizes the history and the current knowledge of sutureless valve technology.

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.

Costs of transcatheter versus surgical aortic valve replacement in intermediate-risk patients

Transcatheter aortic valve replacement (TAVR) offers a new treatment option for patients with aortic stenosis, but costs may play a decisive role in decision making. Current studies are evaluating TAVR in an intermediate-risk population. We assessed the in-hospital and 1-year follow-up costs of patients undergoing TAVR and surgical aortic valve replacement (SAVR) at intermediate operative risk and identified important cost components.

Improvement of physical and mental health after transfemoral transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has emerged as a treatment alternative to surgical aortic valve replacement in elderly high-risk patients with symptomatic severe aortic stenosis. In this patient population, rapid improvement or restoration of quality of life (QoL) is at least as important as improved clinical outcomes. The purpose of the present study was to assess changes in QoL in response to TAVI.

Accidental closure of the left upper pulmonary vein with an Amplatzer atrial septal defect occluder

We report the clinical outcome of a 46-year-old man referred for percutaneous closure of an atrial septal defect under transthoracic echocardiographic and fluoroscopic guidance, whose upper left pulmonary vein was erroneously obliterated using an Amplatzer atrial septal defect occluder. Various medical conditions have been associated with pulmonary vein stenosis including dyspnea on exertion or at rest, cough, and hemoptysis. However, there were no short- or long-term symptoms in this patient.

Transcatheter aortic valve implantation: prevention and management of complications

Assessment of elderly patients with severe aortic stenosis and decisions in terms of management strategy (conservative with or without balloon aortic valvuloplasty, transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement) are complex and warrant a multidisciplinary approach involving collaboration between experienced cardiac surgeons, interventional cardiologists, cardiac imaging specialists, anaesthesiologists, geriatricians and a specialised nursing staff. Patient history, comorbid conditions, perioperative risk stratification as well as anatomical and procedural considerations require careful review on an individual, case-by-case basis and have a major impact on treatment allocation. The aims of this article are to provide insights into the fundamental role of appropriate patient screening and selection, and to review the nature, management and prevention of the most important procedural complications associated with the TAVI procedure.

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.

Comparison of contrast-enhanced multi-station MR angiography and digital subtraction angiography of the lower extremity arterial disease

PURPOSE: To compare diagnostic accuracy of multi-station, high-spatial resolution contrast-enhanced MR angiography (CE-MRA) of the lower extremities with digital subtraction angiography (DSA) as the reference standard in patients with symptomatic peripheral arterial occlusive disease. MATERIALS AND METHODS: Of 485 consecutive patients undergoing a run-off CE-MRA, 152 patients (86 male, 66 female; mean age, 71.6 years) with suspected peripheral arterial occlusive disease were included into our Institutional Review Board approved study. All patients underwent MRA and DSA of the lower extremities within 30 days. MRA was performed at 1.5 Tesla with a single bolus of 0.1 mmol/kg body weight of gadobutrol administered at a rate of 2.0 mL/s at three stations. Two readers evaluated the MRA images independently for stenosis grade and image quality. Sensitivity and specificity were derived. RESULTS: Sensitivity and specificity ranged from 73% to 93% and 64% to 89% and were highest in the thigh area. Both readers showed comparable results. Evaluation of good and better quality MRAs resulted in a considerable improvement in diagnostic accuracy. CONCLUSION: Contrast-enhanced MRA demonstrates good sensitivity and specificity in the investigation of the vasculature of the lower extremities. While a minor investigator experience dependence remains, it is standardizable and shows good inter-observer agreement. Our results confirm that the administration of Gadobutrol at a standard dose of 0.1 mmol/kg for contrast-enhanced runoff MRA is able to detect hemodynamically relevant stenoses. Use of contrast-enhanced MRA as an alternative to intra-arterial DSA in the evaluation and therapeutic planning of patients with suspected peripheral arterial occlusive disease is well justified. J. Magn. Reson. Imaging 2013;37:1427-1435. © 2012 Wiley Periodicals, Inc.

Urogenital manifestations in Wegener granulomatosis: a study of 11 cases and review of the literature

We describe the main characteristics and treatment of urogenital manifestations in patients with Wegener granulomatosis (WG). We conducted a retrospective review of the charts of 11 patients with WG. All patients were men, and their median age at WG diagnosis was 53 years (range, 21-70 yr). Urogenital involvement was present at onset of WG in 9 cases (81%), it was the first clinical evidence of WG in 2 cases (18%), and was a symptom of WG relapse in 6 cases (54%). Symptomatic urogenital involvement included prostatitis (n = 4) (with suspicion of an abscess in 1 case), orchitis (n = 4), epididymitis (n = 1), a renal pseudotumor (n = 2), ureteral stenosis (n = 1), and penile ulceration (n = 1). Urogenital symptoms rapidly resolved after therapy with glucocorticoids and immunosuppressive agents. Several patients underwent a surgical procedure, either at the time of diagnosis (n = 3) (consisting of an open nephrectomy and radical prostatectomy for suspicion of carcinoma, suprapubic cystostomy for acute urinary retention), or during follow-up (n = 3) (consisting of ureteral double J stents for ureteral stenosis, and prostate transurethral resection because of dysuria). After a mean follow-up of 56 months, urogenital relapse occurred in 4 patients (36%). Urogenital involvement can be the first clinical evidence of WG. Some presentations, such as a renal or prostate mass that mimics cancer or an abscess, should be assessed to avoid unnecessary radical surgery. Urogenital symptoms can be promptly resolved with glucocorticoids and immunosuppressive agents. However, surgical procedures, such as prostatic transurethral resection, may be mandatory in patients with persistent symptoms.

Three-dimensional printing of models for preoperative planning and simulation of transcatheter valve replacement

In this study, we show the use of three-dimensional printing models for preoperative planning of transcatheter valve replacement in a patient with an extreme porcelain aorta. A 70-year-old man with severe aortic stenosis and a porcelain aorta was referred to our center for transcatheter aortic valve replacement. Unfortunately, the patient died after the procedure because of a potential ischemic event. Therefore, we decided to fabricate three-dimensional models to evaluate the potential effects of these constructs for previous surgical planning and simulation of the transcatheter valve replacement.

Endovascular stenting of a renal transplant vein

We describe successful endovascular stenting of a high-grade stenosis of a renal transplant vein in a 53-year old patient. Kidney transplantation had been performed due to IgA nephropathy and the patient had become symptomatic two months after uneventful recovery from operation.

A modified calculation of ankle-brachial pressure index is far more sensitive in the detection of peripheral arterial disease

BACKGROUND: Ankle-brachial pressure index (ABI) is a simple, inexpensive, and useful tool in the detection of peripheral arterial occlusive disease (PAD). The current guidelines published by the American Heart Association define ABI as the quotient of the higher of the systolic blood pressures (SBPs) of the two ankle arteries of that limb (either the anterior tibial artery or the posterior tibial artery) and the higher of the two brachial SBPs of the upper limbs. We hypothesized that considering the lower of the two ankle arterial SBPs of a side as the numerator and the higher of the brachial SBPs as the denominator would increase its diagnostic yield. METHODS: The former method of eliciting ABI was termed as high ankle pressure (HAP) and the latter low ankle pressure (LAP). ABI was assessed in 216 subjects and calculated according to the HAP and the LAP method. ABI findings were confirmed by arterial duplex ultrasonography. A significant arterial stenosis was assumed if ABI was <0.9. RESULTS: LAP had a sensitivity of 0.89 and a specificity of 0.93. The HAP method had a sensitivity of 0.68 and a specificity of 0.99. McNemar's test to compare the results of both methods demonstrated a two-tailed P < .0001, indicating a highly significant difference between both measurement methods. CONCLUSIONS: LAP is the superior method of calculating ABI to identify PAD. This result is of great interest for epidemiologic studies applying ABI measurements to detect PAD and assessing patients' cardiovascular risk.

Contrast-enhanced 3-D MRA in decision making for carotid endarterectomy: a 6-year experience

BACKGROUND: Systematic need for angiography in diagnosis of carotid artery stenosis and indication of surgical therapy is still debated. Noninvasive imaging techniques such as MR angiography (MRA) or CT angiography (CTA) offer an alternative to digital subtraction angiography (DSA) and are increasingly used in clinical practice. In this study, we present the radiological characteristics and clinical results of a series of patients operated on the basis of combined ultrasonography (US)/MRA. METHODS: This observational study included all the patients consecutively operated for a carotid stenosis in our Department from October 1998 to December 2004. The applied MRA protocol had previously been established in a large correlation study with DSA. DSA was used only in case of discordance between US and MRA. The preoperative radiological information furnished by MRA was compared with intraoperative findings. The outcome of the operation was assessed according to ECST criteria. RESULTS: Among 327 patients, preoperative MRA was performed in 278 (85%), DSA in 44 (13.5%) and CT angiography in 5 (1.5%). Most of DSA studies were performed as emergency for preparation of endovascular therapy or for reasons other than carotid stenosis. Eleven additional DSA (3.3%) complemented US/MRA, mostly because diverging diagnosis of subocclusion of ICA. No direct morbidity or intraoperative difficulty was related to preoperative MRA. Combined mortality/major morbidity rate was 0.9% (3 patients) and minor morbidity rate 5.5% (18 patients). CONCLUSIONS: This observational study describes a well-established practice of carotid surgery and supports the exclusive use of non invasive diagnostic imaging for indicating and deciding the operation.

Long-term results and complications following uvulopalatopharyngoplasty in 116 consecutive patients

A modified uvulopalatopharyngoplasty (UPPP) was carried out between January 1992 and December 2003 at the ENT Department of the Inselspital in Bern in 146 patients with habitual or complicated rhonchopathy. The operation consisted of a classical tonsillectomy or residual tonsil resection and additional shortening of the uvula. The natural mucosal fold between the uvula and the upper pole of the tonsils was carefully preserved. A wide opening to the rhinopharynx was created by asymmetric suturing of the glossopalantine and pharyngopalatine arches. A retrospective questionnaire with regard to rhonchopathy, phases of apnea, daytime drowsiness, obstruction of nasal breathing, long-term complications and patient satisfaction was used to evaluate the short-term and long-term effectiveness of the modified UPPP as well as the incidence of adverse side effects. Complete postoperative courses were evaluated in 116 patients. Surgical complications were restricted to one case with postoperative hemorrhage. A velum insufficiency or postoperative rhinopharyngeal stenosis did not occur. Eighty-three patients (72%) confirmed a persistent suppression or substantial improvement of the rhonchopathy. Disappearance or decrease of sleep apnea was confirmed in 12 (63%) out of 19 postoperative polysomnographic follow-up investigations. Long-term complications occurred in a total of 27 (23%) of 116 patients. They were confined to minor problems such as dryness of the mouth (n = 12), slight difficulty in swallowing (n = 7), discrete speech disturbances (n = 1), and slight pharyngeal dysesthesias (n = 7) with feeling of a lump in the throat and compulsive clearing of the throat. Eighty-five patients (73%) reported that they were satisfied with the postoperative result even several years after the operation. Looking back, 31 patients (27%) would no longer have the operation performed. The inadequate result of the rhonchopathy was specified as the reason by 21 patients. Ten patients had unpleasant memories of the operation because of intensive postoperative pain. Snoring and apneic phases are suppressed or improved by non-traumatic UPPP in the majority of patients. This effect persisted even years after the operation.

Improved neo-endothelialization of small diameter ePTFEgrafts with titanium coating

BACKGROUND: Patency of small synthetic bypass grafts is inferior compared to autologous grafts for revascularization procedures. Titanium coating of foreign surfaces has shown to decrease thrombogenicity, enhance biocompatibility and promote adhesion of endothelial cells. The aim of this study was to test the effect of titanium coating of small diameter ePTFE grafts on short term patency, neo-endothelialization and neointimal proliferation. METHODS: Bilateral carotid graft interposition was performed in 5 pigs with uncoated (n=5) and titanium-coated (n=5) ePTFE grafts (internal diameter=4 mm, length=5 cm), thus each pig served as its own control. At the end of the study (30 +/- 3 days), patency and stenosis severity was assessed by carotid angiography. Animals were sacrificed and grafts were excised for histology and scanning electron microscopy. Morphometry of histologic sections was carried out to determine neointimal proliferation and percentage of neo-endothelial coverage. RESULTS: Patency rate was 80% for uncoated and titanium-coated grafts. Quantitative angiography did not show any significant difference in lumen size between two groups. Morphometry revealed a significantly higher cellular coverage with CD31 positive endothelial cells for titanium-coated (84 +/- 19%) than uncoated grafts (48 +/- 26%, p<0.001). There was a non significant trend (p=0.112) towards increased neointimal proliferation in titanium-coated (94 +/- 61 micron2/micron) compared to uncoated grafts (60 +/- 57 micron2/micron). CONCLUSIONS: Patency rate in uncoated and titanium-coated ePTFE grafts is similar at one month. However, titanium coated grafts show a significant improvement in neo-endothelialization compared to uncoated grafts.