Malin Johansson

Transapical Versus Transfemoral Aortic Valve Implantation: A Comparison of Survival and Safety

BACKGROUND Transcatheter aortic valve implantation (TAVI) is a therapeutic option for high-risk patients with aortic stenosis. Procedural mortality remains high in comparison with conventional aortic valve replacement (AVR) because patients determined for TAVI are commonly denied conventional surgery. We aimed to evaluate access-related complications between the transfemoral (TF) and the transapical (TA) approach and to compare survival between TAVI and conventional AVR in propensity-score-matched patients. METHODS Between January 2008 and November 2009, 40 patients underwent TAVI (TF, n=10; TA, n=30) with the Edwards Sapien bioprosthesis (Edwards Lifesciences, Irvine, CA). Survival and postoperative complications were evaluated between the TF and the TA approach. A comparison of survival was made between the TAVI patients and propensity-score-matched patients undergoing conventional AVR. RESULTS Successful implantation rate was 92.5% (37 of 40). Thirty-day mortality was 5.0% (2 of 40), and the overall in-hospital mortality was 10.0% (4 of 40). Survival after TAVI was 77% at both 6 months and 1 year. Major vascular complications occurred in 3 of 10 patients (all in the TF group), and 3 of 40 patients (7.5%) suffered cerebrovascular events. A comparison of survival between TAVI and propensity score-matched conventional AVR patients showed no significant difference in either the TA group (p=0.73) or the TF group (p=0.59). CONCLUSIONS The vascular complications occurring when using the TF approach were probably related to a combination of a wide introducer sheath and heavily calcified femoral arteries in a high-risk population. No serious complications were encountered when using the TA approach. After propensity-score matching, survival with both the TA and TF approaches is similar to that after AVR.

Acute Kidney Injury Assessed by Cystatin C after Transcatheter Aortic Valve Implantation and Late Renal Dysfunction.

OBJECTIVE The aim of the present study was to evaluate acute kidney injury (AKI) with cystatin C following transcatheter aortic valve implantation (TAVI) and to assess the impact of postoperative AKI on outcome and late renal function. DESIGN A prospective study. SETTING Single, tertiary referral center. PARTICIPANTS Sixty-eight consecutive patients with severe aortic stenosis and advanced comorbidity. INTERVENTIONS Blood samples were collected on 4 occasions pre- and postoperatively to determine levels of s-creatinine and cystatin C. Additionally, a sample was collected at followup 12 months postoperatively for the determination of s-creatinine. MEASUREMENTS AND MAIN RESULTS The mean preoperative eGFR (s-creatinine) was 67±24 mL/min/1.73 m² compared to 45±21 mL/min/1.73 m² with eGFR (cystatin C) (p<0.001). Postoperative AKI was diagnosed in 25 patients (39%) with eGFR (cystatin C), compared to 21 patients (33%) with GFR (s-creatinine) and the RIFLE criteria. The 90-day mortality was 14.3% for the AKI+group and 2.3% for the AKI-group (p = 0.099). At 12 months followup, renal function remained impaired in patients with postoperative AKI and deteriorated in patients without. CONCLUSIONS The risk of postoperative AKI is considerable following TAVI, with an increased risk of early mortality for AKI+patients. Cystatin C may be a valuable adjunct to the established biomarker s-creatinine for preoperative risk assessment and for early postoperative diagnosis of AKI. The acute postoperative renal impairment in patients with AKI does not fully recover in the long term. There is a progressive renal impairment in both groups postoperatively, the etiology probably being multifactorial.

Fondaparinux or enoxaparin: A comparative study of postoperative bleeding in coronary artery bypass grafting surgery.

Abstract Objectives. Preoperative treatment with anti-coagulants for patients with non-ST-elevation acute coronary syndromes (NSTE-ACS) exposes patients undergoing surgical revascularization to a higher risk of perioperative bleeding. The aim of this study was to compare the effect on bleeding and transfusion needs during cardiac surgery for patients treated with enoxaparin or fondaparinux. Design. Using a combined retrospective and prospective approach, we studied the outcome of 147 patients with NSTE-ACS referred to coronary artery bypass grafting in terms of bleeding, blood transfusions and other complications. Results. Eighty patients were treated preoperatively with enoxaparin, and 67 patients with fondaparinux. There was no significant difference in postoperative bleeding (532 ± 355 for enoxaparin group vs. 580 ± 300 ml for fondaparinux group, p = ns) or transfusion needs for the two groups. A subgroup analysis of the fondaparinux group showed a significantly higher amount of postoperative bleeding after 12 h for patients when preoperative treatment with fondaparinux was discontinued less than 36 h prior to surgery compared to more than 36 h. Discussion. This study suggests that preoperative treatment with fondaparinux for NSTE-ACS is as safe as enoxaparin in terms of postoperative bleeding and transfusion needs. Findings support discontinuation of fondaparinux at 36 h prior to surgery.

Biocompatible sample pretreatment for immunochemical techniques using micellar liquid chromatography for separation of corticosteroids

Micellar liquid chromatography (MLC) using Tween 20 as surfactant was evaluated as a biocompatible sample pretreatment preceding immunoassay in order to obtain an increased selectivity of the assay and a simplification of the sample pretreatment procedure. Different stationary phases and chromatographic conditions were studied for the separation of budesonide and cortisol and some steroids known to interfere in immunoassay of these compounds. The separation was dependent on several parameters, for example, temperature, the concentration of Tween 20, pH and ionic strength of the mobile phase, and nature of the stationary phase. A precolumn venting system was used, which allowed for 140 direct injections of 25 microliters of human blood plasma, without loss of chromatographic performance. Results obtained from the coupling of MLC to an immunoassay for cortisol illustrates the selectivity which can be obtained, and that simplification of the sample pretreatment is possible using this technique.

Late survival and heart failure after transcatheter aortic valve implantation.

Background Short-term survival in patients undergoing transcatheter aortic valve implantation is favorable. Our aim was to evaluate late survival and composite clinical endpoints specified by the Valve Academic Research Consortium-2, including rehospitalization for congestive heart failure. Methods Between January 2008 and April 2014, 166 consecutive patients with severe symptomatic aortic stenosis underwent 168 transcatheter aortic valve implantation procedures at our facility. This cohort was compared with propensity score-matched aortic valve replacement patients. Event rates were estimated by the Kaplan-Meier method and compared using the log-rank test. Cox regression analysis was performed to determine predictors of outcome. Results Although 30-day mortality rates following both procedures were similar (4.2% and 4.8%; p = 0.81), significant differences were seen in corresponding rates of survival (51.7% ± 5.8% vs. 72.3% ± 4.3%; p < 0.001) and cumulative rehospitalization for congestive heart failure (41.3% ± 7.2% vs. 23% ± 4.3%; p = 0.006). New York Heart Association functional class IV preoperative status was an independent risk factor for rehospitalization due to congestive heart failure (p = 0.015). Conclusions This study confirms the merit of transcatheter aortic valve implantation in high-risk patients with aortic stenosis, although late survival proved inferior to that of aortic valve replacement in propensity score-matched subjects. Early safety was excellent for both treatment groups, however, patients undergoing transcatheter aortic valve implantation had a higher incidence of rehospitalization for congestive heart failure and myocardial infarction during follow-up. Patients with severe congestive heart failure should be carefully monitored and aggressively treated to improve outcomes.

Myocardial topical negative pressure increases blood flow in hypothermic, ischemic myocardium

Objectives. Hypothermia protects the myocardium from oxidative injury during ischemic stress and reperfusion. We have previously shown that topical negative pressure (TNP) of −50 mmHg significantly increases microvascular blood flow in the underlying myocardium in normal, ischemic, and reperfused porcine myocardium. The present study was designed to elucidate the effect of TNP between −50 mmHg and −150 mmHg on microvascular blood flow in ischemic myocardium during hypothermia. Design. The microvascular blood flow in the myocardium was recorded, in seven pigs, using laser Doppler velocimetry. Analyses were performed in the epicardium and in the myocardium, after 40 minutes of occlusion of the LAD followed by cooling to 31°C. Results. A TNP of −50 mmHg applied to the epicardium, from 23.3±3.8 PU to 104.2±31.3 PU (*p<0.05), and in the myocardium, from 35.0±7.2 PU to 74.2±21.8 PU (*p<0.05). Conclusions. Only a TNP level of −50 mmHg significantly increased the microvascular blood flow in both the epicardium and in the myocardium during hypothermia.

Manufacturing relocation through offshoring and backshoring : The case of Sweden

Purpose The purpose of this paper is to present recent empirical results concerning offshoring and backshoring of manufacturing from and to Sweden, to increase the understanding of manufacturing relocation in an international context. In particular, extent, geographies, type of production, drivers, and benefits of moving manufacturing in both directions are investigated. Design/methodology/approach The study is based on survey data from 373 manufacturing plants. The same set of questions is used for both offshoring and backshoring between 2010 and 2015, which allows similarities and differences in decision-making and results between the two relocation directions to be identified. Findings There are many significant differences between offshoring and backshoring projects. Labour cost is the dominating factor in offshoring, as driver and benefit, while backshoring is related to many drivers and benefits, such as quality, lead-time, flexibility, access to skills and knowledge, access to technology, and proximity to RD labour-intensive production is offshored and complex production is backshored. Research limitations/implications Plants that have both offshored and backshored think and act differently than plants that have only offshored or backshored, which is why it is important to distinguish between these plant types in the context of manufacturing relocations. Practical implications The experience of Swedish manufacturing plants reported here can be used as a point of reference for internal manufacturing operations. Originality/value The survey design allows a unique comparison between offshoring and backshoring activity. Since Swedish firms in general have been quite active in rearranging their manufacturing footprint and have experience from movements in both directions, it is an appropriate geographical area to study in this context.