Outcomes of transcatheter aortic valve implantation compared to surgical aortic valve replacement following previous surgery.

BACKGROUND AND AIM OF THE STUDY: Surgical aortic valve replacement remains the 'gold standard' treatment for aortic valve disease. An increasing number of elderly patients with multiple comorbidities are referred for transcatheter aortic valve implantation (TAVI), partly due to the perceived high risks of surgery. These include in particular patients who have had previous cardiac surgery. The study aim was to compare the outcomes of patients with aortic valve disease and previous cardiac surgery who underwent TAVI, with those who had redo surgery. METHODS: Patients were identified with aortic valve disease and previous cardiac surgery referred to the authors' multidisciplinary meeting. Patient characteristics were noted, together with their allocation to either re-do surgery or TAVI. A total of 20 patients who had undergone previous cardiac surgery was allocated to TAVI; these were matched to 20 patients who had undergone previous surgery and subsequently had redo surgery. Treatment modalities were chosen for individual patients according to their EuroSCORE, together with other factors not accounted for in traditional scoring systems. RESULTS: Between June 2008 and March 2010, a total of 191 patients was discussed; of these patients, 63 underwent TAVI, 20 of whom had undergone previous cardiac surgery. There was no significant difference in the EuroSCORE between groups (18 +/- 2 versus 19 +/- 3.0, p = 0.91). TAVI patients had a higher body mass index (27.1 +/- 3.9 versus 21.8 +/- 0.5 kg/m2, p = 0.0001). There were no deaths at 30 days in either group. One patient (5%) in the TAVI group had a transient ischemic attack following the procedure, and one (5%) had a hematoma at the site of arterial puncture. There were more pacemaker implantations in the TAVI group than in the redo group (25% versus 0%, p = 0.02). CONCLUSION: Improved risk stratification and its understanding in patients with aortic valve disease and previous cardiac surgery is required. Despite the perceived high risks in the surgically treated group, there were no deaths and redo surgery patients had lower rates of stroke and pacemaker implantation than did those who underwent TAVI.

Spontaneous Coronary Artery Dissection: The Phantom Menace.

We present a case of a 66-year-old lady with chest pain, without dynamic 12-lead electrocardiographic (ECG) changes and normal serial troponin. Coronary angiography revealed a linear filing defect in the first obtuse marginal branch of the circumflex artery indicating coronary artery dissection, with superadded thrombus. She was managed medically with dual antiplatelet therapy and has responded well. Spontaneous coronary artery dissection (SCAD) is a rare cause of cardiac chest pain, which can be missed without coronary angiography. Unlike most other lesions in patients with unstable symptoms, where coronary intervention with stenting is recommended, patients with SCAD generally fare better with conservative measures than with intervention, unless there is hemodynamic instability.

Bicuspid aortic valve aortopathy: genetics, pathophysiology and medical therapy.

The association between ascending aortic aneurysm (AA) and bicuspid aortic valve (BAV) has been well established. Different genetic, haemodynamic and cardiovascular risk factors have been implicated in the development and progression of AA. However, to date, definite conclusions cannot be drawn regarding the exact molecular, cellular and haemodynamic mechanisms causing BAV-associated aortopathy. For this study, we performed a thorough electronic systematic review of the literature using MEDLINE (1960-2012) and EMBASE databases. MeSH terms included: 'bicuspid aortic valve and ascending aorta', 'bicommissural aortic valve and aneurysm', 'bicuspid aortopathy', 'bicuspid aortic valve pathophysiology', 'bicuspid aortic valve and genetics' and 'bicuspid aortic valve and treatment'. We aim in this review to discuss the mechanisms, pathophysiology, genetics and modern drug therapy in the context of BAV-associated aortopathy.

Proteomics in aortic aneurysm--what have we learnt so far?

Aortic aneurysm is a deceptively indolent disease that can cause severe complications such as aortic rupture and dissection. In the normal aorta, vascular smooth muscle cells within the medial layer produce and sustain the extracellular matrix (ECM) that provides structural support but also retains soluble growth factors and regulates their distribution. Although the ECM is an obvious target to identify molecular processes leading to structural failure within the vessel wall, an in-depth proteomics analysis of this important sub-proteome has not been performed. Most proteomics analyses of the vasculature to date used homogenized tissue devoid of spatial information. In such homogenates, quantitative proteomics comparisons are hampered by the heterogeneity of clinical samples (i.e. cellular composition) and the dynamic range limitations stemming from highly abundant cellular proteins. An unbiased proteomics discovery approach targeting the ECM instead of the cellular proteome may decipher the complex, multivalent signals that are presented to cells during aortic remodelling. A better understanding of the ECM in healthy and diseased vessels will provide important pathogenic insights and has potential to reveal novel biomarkers.

Dilatation of the remaining aorta after aortic valve or aortic root replacement in patients with bicuspid aortic valve: a 5-year follow-up.

BACKGROUND: The natural history and management of ascending aorta (AA) and arch dilatation in patients with bicuspid aortic valve (BAV) after aortic valve replacement (AVR) or aortic root replacement (ARR) remains controversial. Our aim is to identify dilatation of the remaining aorta after AVR or ARR in patients with BAV compared with patients with tricuspid aortic valve (TAV). METHODS: Three hundred ninety-five patients who underwent AVR or ARR between 2002 and 2009 were studied. Preoperative computed tomography (CT) and echocardiography were performed in 192 patients with BAV, and the results were compared with those of 203 patients with TAV. An AA diameter 4.5 cm or greater was regarded as aneurysmal. Postoperative echocardiograms, computed tomographic scans, and magnetic resonance images were compared with subsequent imaging at a median follow-up of 4.6 years (2.2-9.8 years). RESULT: Median ages of patients with BAV and patients with TAV were 57 ± 14 and 65 ± 16 years, respectively (p < 0.05). Preoperative diameter of AA in the BAV group with no aneurysm (3.5 cm; range, 3.0-4.0 cm; n = 143) was significantly higher than in the TAV group (3.3 cm; range, 3.1-3.8 cm; n = 129) (p < 0.001). In both BAV and TAV groups with nonaneurysmal aortas who underwent AVR, there was no significant expansion of the AA and arch at 5 years' follow-up. In patients with aneurysmal aorta (BAV group, n = 49; TAV group, n = 74) who underwent ARR, there was also no significant difference in growth of the remaining aorta at 3 and 5 years' follow-up. CONCLUSIONS: No significant dilatation of the AA or arch was observed after AVR or ARR, respectively, in patients when a cut-off diameter of 4.5 cm or greater was considered for replacement in patients with BAV compared with patients with TAV up to 5 years after operation. The need for aortic replacement at smaller diameters was not found.

High-Volume Practice by a Single Specialized Team Reduces Mortality and Morbidity of Elective and Urgent Aortic Root Replacement.

BACKGROUND: Elective aortic root replacement (ARR), or the Bentall procedure, is associated with significant mortality and complications. Recent studies have shown that high procedure volume has an inverse association with postoperative mortality. The outcomes of patients undergoing elective/urgent ARR by a single, high-volume surgical team were assessed in this study. METHODS: Patients undergoing nonemergency, elective/urgent ARR for non-Marfan aortic root dilatation, from October 2005 to March 2011, were studied. Valve-preserving procedures, extra-anatomic bypass, and arch and descending aortic repairs were excluded. Patient demographics, operative details, and postoperative outcomes were collected prospectively. Surgical techniques included central cannulation and cardiopulmonary bypass (CPB) at 35°C. Following aneurysm excision, a composite valve-conduit reconstruction with coronary button reimplantation was performed. Tissue glue, Teflon pledgets, and blood products were seldom used. Patients were followed locally at 8 weeks, 6 months, and annually thereafter with echocardiography and computed tomographic (CT) scanning. RESULTS: From October 2005 to March 2011, 163 ARRs were performed. Of these, 131 (80%) were isolated first time procedures (four in pregnant women), six were redo (4%), and in 26 (16%) ARR was combined with concomitant valve or coronary artery revascularization procedures. Median age was 63 years (range 19-84). Median cross-clamp and CPB times were 73 (range 69-87) and 86 minutes (range 85-126), respectively. There was one in-hospital death (mortality = 0.6%), one patient underwent resternotomy for bleeding, two required hemofiltration, and there were no strokes. Median hospital stay was 6 days (range 5-11). Median follow-up was 2.9 years (range 6 months-4.3 years) with 100% freedom from reoperation. There was no late distal ascending aorta/arch dilatation. There were two late deaths (1.2%) due to pneumonia and stroke. CONCLUSIONS: High-volume surgery, with minimal use of hemostatic adjuncts and sustained follow-up, leads to excellent outcomes, with low morbidity and mortality following ARR.

Acute kidney injury after transcatheter aortic valve implantation: incidence, risk factors, and prognostic effects.

OBJECTIVE: Acute kidney injury (AKI) is a common complication after surgical aortic valve replacement and is associated with increased mortality. Transcatheter aortic valve implantation (TAVI) is now considered the criterion standard treatment of patients with severe symptomatic aortic stenosis ineligible for surgery. The aim of this study was to establish the incidence, risk factors, and prognostic consequences of AKI after TAVI and at 1-year follow-up in a single center. METHODS: Between December 2007 and March 2011, a total of 79 patients with severe aortic stenosis who underwent 81 TAVI procedures with the Medtronic CoreValve System or the Edwards SAPIEN heart valve were included. Baseline characteristics and procedural complications were recorded. Acute kidney injury was defined according to the Valve Academic Research Consortium criteria (modified risk, injury, failure, loss, and end-stage kidney disease criteria). RESULTS: The mean age was 84 (78-87) years; 49 were men. After TAVI, 10 patients (12.3%) developed AKI, which had completely resolved in 9 patients before hospital discharge. Nine patients (10%) had mild AKI (stage 1) and only one patient (10%) experienced moderate AKI (stage 2) according to Valve Academic Research Consortium definitions. The predictive factors of AKI were diabetes (odds ratio, 6.722; P = 0.004) and preoperative creatinine level greater than 104 µmol/L (odds ratio, 1.024; P = 0.02). Thirteen patients (16.4%) died within 1 year after TAVI. Three of the nonsurvivors (3.7%) developed AKI postoperatively. Acute kidney injury was, however, not a predictive factor of 1-year mortality after TAVI. CONCLUSIONS: Acute kidney injury occurred in 12.3% of the patients after TAVI and persisted in only one patient before hospital discharge. Diabetes and preoperative creatinine level were found to be the main predictive factors of AKI after TAVI. Acute kidney injury was not associated with increased 1-year mortality.

Outcome of patients with aortic stenosis referred to a multidisciplinary meeting for transcatheter valve.

BACKGROUND: Until recently, many elderly patients with symptomatic aortic stenosis and multiple risk factors were untreated due to perceived risks of surgery. With the advent of transcatheter aortic valve implantation there has been a surge in referral for treatment. We present the outcome of patients referred to a multidisciplinary meeting. METHODS: A total of 175 patients were reviewed between January 2008 and March 2010. Patients' characteristics, investigations, and their outcome designated for transcatheter aortic valve implantation, surgical aortic valve replacement, and medical therapy were studied. The decision making process was a combination of known risk factors accounted for in the European system for cardiac operative risk evaluation and factors unaccounted for in traditional scoring systems. RESULTS: Sixty-three patients underwent transcatheter implantation, 74 underwent surgical valve replacement, and 38 were treated medically. There were no deaths at 30 days in the transcatheter or surgical group. There were more strokes (6.3% vs 1.4%, p = 0.057) and pacemaker implantations (25% vs 0, p = 0.0001) in the transcatheter group compared with the surgical group. The patients in the transcatheter group had shorter ventilation and intensive care stays. Similar numbers were discharged home or to their original residence. At median follow-up of 466 days, more patients had paravalvular and central aortic valve regurgitation in the transcatheter group. At one year there were more deaths in the medically managed group (30%), compared with the transcatheter (17%) or surgical groups (4%). CONCLUSIONS: Symptomatic high-risk aortic valve patients have a good outcome after transcatheter aortic valve implantation or surgery. Forty-two percent of patients referred for transcatheter aortic valve implantation had surgery and did well. The medically managed group have a poor outcome.