Mobile PCR-based surveillance for SARS-CoV-2 to reduce visiting restrictions in nursing homes during the COVID-19 pandemic: a pilot study.

PURPOSE: Residents in nursing homes for the elderly (NH) are at high risk for death from COVID-19. We investigated whether repeated non-mandatory RT-PCR SARS-CoV-2 surveillance of NH staff and visitors reduces COVID-19 incidence rates in NH residents and allows to reduce visiting restrictions. METHODS: This pilot study at the beginning of the COVID-19 pandemic compared a surveillance approach of regular, twice-weekly voluntary PCR testing of health-care workers (HCW) and visitors in interventional NH (INH) with a setting without regular testing in control NH (CNH). Residents were not tested routinely within this study. Testing was performed in a mobile testing site with same-day result reporting. SARS-CoV-2 incidence among residents in both INH and CNH was the primary endpoint; secondary endpoints being SARS-CoV-2 infection among visitors and HCW in INH. RESULTS: Two INH and two CNH participated between October and December, 2020. At INH1, 787 tests of HCW and 350 tests of visitors were performed, accounting for 18.1% (n = 1930) of visits. At INH2, 78 tests of HCW and 372 tests of visitors were done, i.e., 30.5% (n = 1220) of visits. At the two INH 23 HCW and three visitors tested positive for SARS-CoV-2. COVID-19 outbreaks occurred among residents in INH1 (identified through study testing) and in CNH1. Utilization of voluntary testing was low. CONCLUSION: In a real-world setting without available rapid testing, voluntary RT-PCR SARS-CoV-2 testing of HCW and visitors does not prevent COVID-19 outbreaks in NH. Complete, non-selective testing for these groups should be instituted before visiting restrictions can be reduced. TRIAL REGISTRATION: The study has been registered at ClinicalTrials.gov with the identifier: NCT04933981.

Web-based, rapid and contactless management of ambulatory patients for SARS-CoV-2-testing.

BACKGROUND: During the SARS-CoV-2 pandemic a mass casualty incident of ambulatory patients occurred at the COVID-19 rapid response infrastructure (CRRI) facility at the University Hospital of Cologne (UHC). We report the development of a patient-centred mobile-device solution to support efficient management of the facility, triage of patients and rapid delivery of test results. METHODS: The UHC-Corona Web Tool (CWT) was developed as a web-based software useable on each patient's smartphone. It provides, among others, a self-reported medical history including type and duration of symptoms and potential risk contacts and links all retrieved information to the digital patient chart via a QR code. It provides scheduling of outpatient appointments and automated transmission of SARS-CoV-2 test results. RESULTS: The UHC-CWT was launched on 9 April 2020. It was used by 28,652 patients until 31 August 2020. Of those, 15,245 (53,2%) consulted the CRRI, representing 43,1% of all CRRI patients during the observed period. There were 8304 (29,0%) specifications concerning travel history and 17,145 (59,8%) indications of ≥1 symptom of SARS-CoV-2 infection. The most frequently indicated symptoms were sore throat (60,0%), headache (50,7%), common cold (45,1%) and cough (42,6%) while 11,057 (40,2%) patients did not report any symptoms. After implementation of the UHC-CWT, the amount of patient contacts per physician rose from 38 to 98,7 per day. The personnel for communication of test results were reduced from four on seven days to one on five days. CONCLUSION: The UHC-CWT is an effective digital solution for management of large numbers of outpatients for SARS-CoV-2 testing.

Rapid response infrastructure for pandemic preparedness in a tertiary care hospital: lessons learned from the COVID-19 outbreak in Cologne, Germany, February to March 2020.

The coronavirus disease (COVID-19) pandemic has caused tremendous pressure on hospital infrastructures such as emergency rooms (ER) and outpatient departments. To avoid malfunctioning of critical services because of large numbers of potentially infected patients seeking consultation, we established a COVID-19 rapid response infrastructure (CRRI), which instantly restored ER functionality. The CRRI was also used for testing of hospital personnel, provided epidemiological data and was a highly effective response to increasing numbers of suspected COVID-19 cases.

Control measures following a case of imported Lassa fever from Togo, North Rhine Westphalia, Germany, 2016.

In a patient transferred from Togo to Cologne, Germany, Lassa fever was diagnosed 12 days post mortem. Sixty-two contacts in Cologne were categorised according to the level of exposure, and gradual infection control measures were applied. No clinical signs of Lassa virus infection or Lassa specific antibodies were observed in the 62 contacts. Thirty-three individuals had direct contact to blood, other body fluids or tissue of the patients. Notably, with standard precautions, no transmission occurred between the index patient and healthcare workers. However, one secondary infection occurred in an undertaker exposed to the corpse in Rhineland-Palatinate, who was treated on the isolation unit at the University Hospital of Frankfurt. After German authorities raised an alert regarding the imported Lassa fever case, an American healthcare worker who had cared for the index patient in Togo, and who presented with diarrhoea, vomiting and fever, was placed in isolation and medevacked to the United States. The event and the transmission of Lassa virus infection outside of Africa underlines the need for early diagnosis and use of adequate personal protection equipment (PPE), when highly contagious infections cannot be excluded. It also demonstrates that larger outbreaks can be prevented by infection control measures, including standard PPE.

Preoperative intra-aortic counterpulsation in high-risk patients undergoing cardiac surgery: a meta-analysis of randomized controlled trials†.

In contrast to the results of previous studies, recent randomized controlled trials (RCTs) failed to show a benefit of prophylactic aortic counterpulsation in high-risk patients undergoing cardiac surgery. The present analysis aims to redefine the effects of this treatment modality in the light of this new evidence. MEDLINE, EMBASE, CENTRAL/CCTR, Google Scholar and reference lists of relevant articles were searched for full-text articles of RCTs in English or German. Assessments for eligibility, relevance, study validity and data extraction were performed by two reviewers independently using prespecified criteria. The primary outcome was hospital mortality. A total of nine eligible RCTs with 1171 patients were identified: 577 patients were treated preoperatively with intra-aortic balloon pump (IABP) and 594 patients served as controls. The pooled odds ratio (OR) for hospital mortality (22 hospital deaths in the intervention arm, 54 in the control group) was 0.381 (95% CI 0.230-0.629; P < 0.001). The pooled analyses of five RCTs including only patients undergoing isolated on-pump coronary artery bypass grafting (n[IABP] = 348, n[control] = 347) also showed a statistically significant improvement in mortality for preoperative IABP implantation (fixed-effects model: OR 0.267, 95% CI 0.129-0.552, P < 0.001). The pooled OR for hospital mortality from two randomized off-pump trials was 0.556 (fixed-effects model, 95% CI 0.207-1.493, P = 0.226). Preoperative aortic counterpulsation was associated with a significant reduction in low cardiac output syndrome (LCOS) in the total population (fixed-effects model: OR 0.330, 95% CI 0.214-0.508, P < 0.001) as well as in the subgroup of CAGB patients (fixed-effects model: OR 0.113, 95% CI 0.056-0.226, P < 0.001), whereas there was no benefit in the off-pump population (fixed-effects model: OR 0.555, 95% CI 0.209-1.474, P = 0.238). Preoperative IABP implantation was associated with a reduction of intensive care unit (ICU) stay in all investigated populations with a greater effect in the total population [fixed-effects model: standard mean difference (SMD) -0.931 ± 0.198, P < 0.001] as well as in the subgroup of CAGB patients (fixed-effects model: SMD -1.240 ± 0.156, P < 0.001), compared with the off-pump group (fixed-effects model: SMD -0.723 ± 0.128, P < 0.001). Despite contradictory results from recent trials, the present study confirms the findings of previous meta-analyses that prophylactic aortic counterpulsation reduces hospital mortality, incidence of LCOS and ICU requirement in high-risk patients undergoing on-pump cardiac surgery. However, owing to small sample sizes and the lack of a clear-cut definition of high-risk patients, an adequately powered, prospective RCT is necessary to find a definite answer to the question, if certain groups of patients undergoing cardiac surgery benefit from a prophylactic IABP insertion.

Comparison of the Avalon Dual-Lumen Cannula with Conventional Cannulation Technique for Venovenous Extracorporeal Membrane Oxygenation.

BACKGROUND: Comparison of two kinds of cannulation (double-lumen cannula [DLC, Avalon Elite Bicaval Dual Lumen Catheter] and conventional cannulation with two cannulas) for venovenous extracorporeal membrane oxygenation (ECMO) therapy in terms of effectiveness, usage complexity, and costs. METHODS: Retrospective case series of 17 patients who received venovenous ECMO therapy due to acute respiratory distress syndrome (ARDS) between January 2010 and March 2012. Nine patients were treated with the DLC and eight patients with conventional cannulation. We analyzed the outcome data, ECMO values, respirator settings, blood gas values, realized prone positioning, and costs, and compared both methods. RESULTS: Both kinds of cannulation are efficient regarding oxygenation and decarboxylation. There is no significant difference in mortality, hospitalization time (intensive care unit [ICU] and hospital) and complications during ECMO therapy between both groups. Cannula implantation is much more complex in the DLC group and requires more experience in TEE (transesophageal echocardiography) diagnostics and cannulation technique. In addition, the costs for the Avalon (MAQUET Cardiopulmonary AG, Germany) cannula are significantly higher than for conventional cannulation. Furthermore, prone positioning could be easier achieved in the DLC group. CONCLUSION: In summary, double-lumen cannulation allows sufficient gas exchange with more effort (material, technical, and physicians' experience) and higher costs but better mobilization possibilities (particularly prone position) and potential avoidance of deep sedation and mechanical ventilation. From the current point of view, the DLC should be reserved for special cases.

[S3-Guideline: Recommendations for intra-aortic balloon pumping in cardiac surgery]. / S3-Leitlinie "Einsatz der intraaortalen Ballongegenpulsation in der Herzchirurgie".

Although intra-aortic balloon pumping (IABP) is the most frequently used mechanical cardiac assist device in cardiothoracic surgery, there are only guidelines for substantive sections of aortic counterpulsation including prophylactic and postoperative use. In contrast, evidence-based recommendations are still lacking concerning intraoperative use, management, contraindication and other relevant issues. According to international surveys, important aspects of IABP usage show a wide variation in clinical practice. The results of a national questionnaire performed before initiation of this guideline confirmed these findings and demonstrated a clear need for the development of a consensus-based guideline. Therefore, the presented multidisciplinary S-3-guideline was developed under the direction of the German Society for Thoracic and Cardiovascular Surgery (Deutsche Gesellschaft für Thorax-, Herz- und Gefäßchirurgie, DGTHG) to make evidence-based recommendations for the usage of aortic counterpulsation after cardiothoracic surgery according to the requirements of the Association of the Scientific Medical Societies in Germany (AWMF) and the Medical Centre for Quality (Ärztliches Zentrum für Qualität - (ÄZQ)). Main topics discussed in this guideline involve IABP support in the prophylactic, preoperative, intraoperative and postoperative setting as well as the treatment of right heart failure, contraindications, anticoagulation, monitoring, weaning, and limitations of IABP therapy. The presented 15 key messages of the guideline were approved after two consensus meetings under moderation of the AWMF with participation of the German Society of Cardiology (DGK), German Society of Anaesthesiology and Intensive Care Medicine (DGAI), German Interdisciplinary Association for Intensive Care (DIVI) and the German Society for Cardiovascular Engineering (DGfK).

A novel treatment strategy of new onset atrial fibrillation after cardiac surgery: an observational prospective study.

OBJECTIVE: The aim of this prospective observational study was to evaluate the efficiency of a new escalating treatment strategy with vernakalant, flecainide and electrical cardioversion (EC) in patients with new onset atrial fibrillation (AF) after cardiac surgery. MATERIAL AND METHODS: 24 patients with new onset AF after aortic valve surgery, coronary artery bypass surgery or combined procedures were evaluated in this study. Additional including criteria were age between 18 and 80, duration of AF less than four days, body weight less than 100 kg and no previous treatment with class I or III antiarrhythmic drugs. Exclusion criteria were poor left ventricular ejection fraction (LVEF < 40%) and history of myocardial infarction within 30 days. The patients were divided into converters and non-converters according to their response to combination treatment with vernakalant and flecainide, and the groups were compared. RESULTS: The mean age of the population was 69.6 ± 6.3 years and 26.1% of patients were female. There were no statistically significant differences between the two groups in terms of height, weight, gender distribution, comorbidities, preoperative medication, left ventricular function and left atrium diameter. Interventricular septum (IVS) in the non-converted group was significantly thicker compared to the converted group: 14.0 ± 1.00 vs. 10.40 ± 2.59 mm (p = 0.036). While 14 patients (60.9%) were successfully converted into stable sinus rhythm by pharmacological treatment with vernakalant and flecainide, 9 patients (39.1%, non-converted group) remained in AF. However, seven of them could be converted after additional EC. CONCLUSION: The combination of vernakalant and flecainide improves the conversion rate into a stable sinus rhythm in postcardiotomy patients with new onset AF compared to single drug therapy. Furthermore it might be an excellent precondition for successful EC in patients who are not converted after using both antiarrhtythmic drugs. Furthermore, left ventricular hypertrophy might be a potential negative predictor of successful pharmacological cardioversion.

In vivo application of tissue-engineered blood vessels of bacterial cellulose as small arterial substitutes: proof of concept?

BACKGROUND: Tissue-engineered blood vessels (TEBVs) represent an innovative approach for overcoming reconstructive problems associated with vascular diseases by providing small-caliber vascular grafts. This study aimed to evaluate a novel biomaterial of bacterially synthesized cellulose (BC) as a potential scaffold for small-diameter TEBV. METHODS: Small-diameter blood vessels with a supramolecular fiber network structure consisting of tubular hydrogels from biodesigned cellulose were created using Gluconacetobacter strains and Matrix reservoir technology. BC tubes (length: 100 mm, inner diameter: 4.0-5.0 mm) were applied to replace the carotid arteries of 10 sheep for a period of 3 mo to gain further insights into (a) functional (in vivo) performance, (b) ability of providing a scaffold for the neoformation of a vascular wall and (c) their proinflammatory potential, and the (d) technical feasibility of the procedure. RESULTS: Preoperative analysis revealed a bursting strength of the grafts of approximately 800 mm Hg and suture retention strength of 4-5 N. Postexplantation analysis showed a patency rate of 50% (n = 5) and physiological performance of the patent grafts at 4, 8, and 12 wk postoperatively, compared with native arteries. Histologic analysis revealed a neoformation of a vascular wall-like structure along the BC scaffold consisting of immigrated vascular smooth muscle cells and a homogeneous endothelialization of the inner graft surface without signs of prothrombogenic or inflammatory potential. Scanning electron microscopy revealed a confluent luminal endothelial cell layer and the immigration of vascular smooth muscle cells into the BC matrix. CONCLUSIONS: BC grafts provide a scaffold for the neoformation of a three-layered vascular wall exhibit attractive properties for their use in future TEBV programs for cardiovascular surgery.

Impact of major non-cardiac complications on outcome following cardiac surgery procedures: logistic regression analysis in a very recent patient cohort.

OBJECTIVES: In this study, we sought to analyse the incidence of major non-cardiac complications and their impact on survival following cardiac surgery procedures in a contemporary patient cohort. We further determined independent predictors of perioperative mortality and created a logistic regression model for prediction of outcome after the occurrence of these complications. METHODS: Prospectively collected data of 5318 consecutive adult patients (mean age 68.9±11.0 years; 29.3% [n=1559] female) undergoing cardiac surgery from January 2009 to May 2012 were retrospectively analysed. Outcome measures were six major non-cardiac complications including respiratory failure, dialysis-dependent renal failure, deep sternal wound infection (DSWI), cerebrovascular accident (CVA), gastrointestinal complications (GIC) and sepsis and their impact on perioperative mortality and hospital length of stay using multivariate regression models. The discriminatory power was evaluated by calculating the area under the receiver operating characteristic curves (C statistic). RESULTS: A total of 1321 complications were observed in 846 (15.9%) patients: respiratory failure (n=432; 8.1%), dialysis-dependent renal failure (n=295; 5.5%), GIC (n=154; 2.9%), CVA (n=151; 2.8%), DSWI (n=146; 2.7%) and sepsis (n=143; 2.7%). Perioperative mortality was 17.0% in patients with at least one major non-cardiac complication and correlated with the number of complications (single, 9.7%; n=53/549; double, 24.0%; n=44/183; ≥3, 41.2%; n=47/114, P<0.001). Six preoperative and four postoperative independent predictors of operative mortality were identified (age (odds ratio [OR] 1.8; 95% confidence interval [CI] 1.3-2.4), peripheral vascular disease (OR 2.6; 95% CI 1.6-4.2), pulmonary hypertension (OR 2.7; 95% CI 1.5-4.9), atrial fibrillation (OR 1.5; 95% CI 1.0-2.3), emergency (OR 5.0; 95% CI 3.4-7.2), other procedures than CABG (OR 1.5; 95% CI 1.0-2.1), postoperative dialysis (OR 4.0; 95% CI 2.6-6.1), sepsis (OR 3.4; 95% CI 2.0-5.6), respiratory failure (OR 3.2; 95% CI 2.2-4.9), GIC (OR 3.2; 95% CI 1.9-5.3)) and included in the logistic model, which accurately predicted outcome (C statistic, 0.892; 95% CI 0.868-0.916). Length of hospital stay was significantly increased according to the number of complications (single: median 15 (IQR 10-24) days, double: 16 (IQR 8-28) days, ≥3: 20 (IQR 13-39) days, P<0.001). CONCLUSIONS: With a worsening in the risk profile of patients undergoing cardiac surgery, an increasing number of patients develop major complications leading to increased length of stay and mortality, which is correlated to the number and severity of these complications. Our predictive model based on preoperative and postoperative variables allowed us to determine with accuracy the perioperative mortality in critically ill patients after cardiac surgery.

Recurrent left atrial and left ventricular thrombosis due to heparin-induced thrombocytopenia: case report and short review.

The combination of heparin-induced thrombocytopenia (HIT) II, left ventricular failure with extracorporeal membrane oxygenation (ECMO) therapy, and recurrent left ventricular thrombosis is rare and predicts a poor outcome. In this case, HIT II occurred after an ischemic cardiogenic shock. We initiated ECMO and intra-aortic balloon pump therapy during coronary artery bypass grafting and ventricular thrombectomy. Despite continued therapeutic therapy with heparin and later argatroban, the patient developed solid and recurrent thrombotic masses in the left atrium and left ventricle.

Coagulation disorders do not increase the risk for bleeding during percutaneous dilatational tracheotomy.

BACKGROUND: Percutaneous dilatational tracheotomy (PDT) is a common procedure. Coagulation disorders represent a relative contraindication for PDT and, therefore, normalization of hemostasis parameters is recommended. Especially patients undergoing cardiac surgery after valve replacement and with any kind of assist device need to require an adequate anticoagulation. This study investigated the impact of impaired hemostasis as a risk factor for bleeding complications retrospectively. METHODS: Patients who underwent PDT (November 2007 to November 2010) were stratified into a high-risk (HR) and low-risk (LR) group in regard to bleeding complications. The following determining factors activated partial thromboplastin time (aPTT > 50 seconds, prothrombin time (PT < 50%), international normalized ratio (INR > 1.4), and platelet count (< 50,000/µL) were assessed. RESULTS: A total of 213 patients underwent PDT (HR = 5/85; LR = 8/128). There was no difference in demographics or intraoperative data. Patients of both groups showed mild bleeding without the need for surgical intervention or transfusion (p = 0.957). There were no severe bleeding nor other procedure-related complications. CONCLUSION: Percutaneous tracheotomy is a safe and feasible procedure in patients with coagulation disorders. Therefore, discontinuation of anticoagulation treatment or normalization of hemostasis prior to the procedure is not necessary.

Transapical aortic valve implantation: experiences and survival analysis up to three years.

BACKGROUND: We determined our 30-day results after transapical aortic valve implantation (TA-AVI) according to Valve Academic Research Consortium criteria, analyzed midterm outcome, and summarize our institutional learning experience. METHODS: From February 2008 to July 2011, 150 high-risk patients underwent TA-AVI. Endpoints of this retrospective analysis were safety as indicated by morbidity and 30-day mortality and midterm survival with a follow-up period up to 3.4 years (mean follow-up 14.1 months). In addition we analyzed our institutional learning curve by comparing the outcome of our first 50 patients (group 1) to the following 100 patients (group 2). RESULTS: Procedural success was 98% (147 patients). All-cause and cardiovascular cause 30-day mortality was 11.3% (n = 17) and 7.3% (n = 11), respectively. The cumulative survival rates were 78.7% at one year, 62.8% at two years, and 50.8% at three years. As compared to group 1, there was a significantly reduced incidence of relevant bleeding complications (0% vs. 14%[n = 7]; p < 0.001) and a reduced incidence of acute kidney injury (35%[n = 35] versus 56% (n = 28); p < 0.05) in group 2, resulting in a combined safety endpoint at 30 days of 22% in group 2 versus 40% in group 1 (p < 0.05). One-year mortality (group 2, n = 20 [20%] versus group 1, n = 10 [20%]; p = 1) and midterm survival (p = 0.998; Hazard ratio 1.001; 95% CI 0.5141 to 1.949) did not differ significantly. CONCLUSIONS: Although the incidence of technical complications decreased significantly over time, 30-day and midterm mortality were unaltered, most likely due to patients' comorbidities. The development of more accurate risk scores may improve future outcome.

Logistic risk model predicting postoperative renal failure requiring dialysis in cardiac surgery patients.

OBJECTIVE: Renal failure requiring dialysis represents a serious complication following cardiac surgery. This study was designed to determine the incidence and predictors of renal failure requiring dialysis in a contemporary patient population. We also aimed to create a model based on these risk factors that could serve as a tool for the prediction of renal failure requiring dialysis. METHODS: Between October 2007 and June 2009, 2511 consecutive patients (mean age 69 ± 12 years, 68% male) underwent on-pump cardiac surgery at our institution. The main outcome investigated was postoperative renal failure requiring temporary or permanent dialysis. Other postoperative parameters included in the analysis were hospital mortality, major morbidity, length of hospital stay, and discharge condition. Predictors of renal failure requiring dialysis were determined using multivariate regression models. The discriminatory power was evaluated by calculating the area under the receiver-operating-characteristic (ROC) curves (c-statistic). RESULTS: Renal failure requiring dialysis occurred in 3.9% (n = 98) of patients. Hospital mortality among patients with dialysis-dependent renal failure was 37.8% compared with a mortality rate of 1.3% in patients without this complication (p<0.001). Multivariate analysis revealed pulmonary hypertension (odds ratio (OR) = 8.1), preoperative renal dysfunction (creatinine >2.0 mg dl⁻¹) (OR=4.6), cardiopulmonary bypass (CPB) time >120 min (OR=3.9), peripheral vascular disease (OR = 3.1), previous myocardial infarction (OR=3.0), atrial fibrillation (OR = 2.8), age > 75 years (OR = 2.6), New York Heart Association (NYHA) class IV (OR = 2.5), and diabetes (OR = 2.0) as independent predictors for postoperative renal failure requiring dialysis. A logistic equation including the coefficients of the regression analysis accurately predicted individual patient's risk for the occurrence of renal failure requiring dialysis (area under the ROC curve: 0.829, 95% confidence interval 0.78-0.86). CONCLUSIONS: Renal failure requiring dialysis remains a serious complication, particularly in patients with pulmonary hypertension and previous renal dysfunction. Our logistic risk model allows the prediction of renal failure requiring dialysis, based on the individual presentation of risk factors and, therefore, helps to determine the perioperative risk in cardiac surgery patients.

Comparison of the Carpentier-Edwards Perimount and St. Jude Medical Epic bioprostheses for aortic valve replacement--a retrospective echocardiographic short-term study.

OBJECTIVE: Stented biological prostheses show different performance related to their design and ultrastructure. Therefore, we compared the Carpentier-Edwards Perimount (Edwards Lifesciences, Irvine, CA, USA) and the St. Jude Medical Epic (SJM Epic; St. Jude Medical Inc., St. Paul, MN, USA) prostheses with respect to their hemodynamic features. METHODS: Eighty-six patients underwent aortic valve replacement for severe aortic stenosis (50 patients), aortic regurgitation (seven patients), or mixed lesion (29 patients) with these randomly assigned bioprostheses (Perimount: 39 patients; SJM Epic: 47 patients). Following informed consent, patients were examined postoperatively (mean 9.7 +/- 4 months after surgery) with a detailed echocardiographic study, quality of life was determined by a standardized questionnaire. RESULTS: Comparing the indexed effective orifice area (0.77 cm(2)/m(2) vs. 0.64 cm(2)/m(2); p = 0.019), the mean pressure gradient (11.15 mmHg vs. 14.80 mmHg; p = 0.004) and the stroke-work loss (6.95% vs. 8.49%; p = 0.025), the Carpentier-Edwards Perimount demonstrated significantly better hemodynamic features than the SJM Epic prosthesis. These effects were more pronounced in the smaller prosthetic sizes. CONCLUSION: The Carpentier-Edwards Perimount prosthesis was less obstructive than the SJM Epic in echocardiographic controls. Patient-prosthesis mismatch as determined by indexed effective orifice area showed no impact on functional recovery.

Lower serum calcium levels are associated with greater calcium hydroxyapatite deposition in native aortic valves of male patients with severe calcific aortic stenosis.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the relationship between serum calcium levels and the degree of calcification found in stenotic aortic valves. METHODS: Using atomic absorption spectroscopy, the hydroxyapatite content of 228 excised human stenotic aortic valves was determined and expressed as a percentage of valve mass. Left heart catheterization preceded valve replacement. In addition, serum levels of calcium and creatinine were determined before native calcific aortic valve excision. RESULTS: Valves from male patients contained more hydroxyapatite than those of female patients (26 +/- 9 versus 22 +/- 9 mass%; p < 0.001). Patients presenting with lower serum calcium levels showed a slight trend towards higher levels of valve calcification (r = -0.15, p = 0.026), but this association appeared only within the subgroup of male patients. Male patients with lowest serum calcium levels displayed greatest valvular hydroxyapatite deposition (1st calcium tertiary: 29.5 +/- 8.9 mass% versus 2nd calcium tertiary 26.4 +/- 7.8 mass% versus 3rd calcium tertiary 21.4 +/- 8.9 mass%; n = 122; p = 0.001; r = -0.25; p = 0.006). This association was even more distinct in male patients with normal serum creatinine levels. Furthermore, serum calcium was inversely and significantly associated with serum C-reactive protein in male patients (r = - 0.34; p < 0.001). CONCLUSION: Serum calcium levels appear to be inversely related to valve calcification in patients with severe calcific aortic stenosis (AS). This finding indicates the importance of systemic calcium metabolism in calcific AS, independent of manifest disorders of calcium metabolism or renal function. Interestingly, this association was evident only in male patients, suggesting a gender-dependent pathogenesis.

Obesity is associated with a slower response to initial phenprocoumon therapy whereas CYP2C9 genotypes are not.

BACKGROUND: Initiation of phenprocoumon therapy is associated with a variable individual response. The CYP2C9 genotype has been shown to influence the response to warfarin therapy, but such an effect on phenprocoumon therapy remains uncertain. METHOD: Two hundred sixty hospital patients started on phenprocoumon were recruited for this study. Body mass index (BMI), waist and hip circumference, dietary habits, comorbidity, and comedication were initially assessed. A 5' exonuclease assay (TaqManR) was used to analyze the presence of five polymorphisms of the CYP2C9 gene in each of the study patients. Study endpoints included the time necessary to achieve the international normalized ratio (INR) target (INR >2) and the total drug amount required to attain target INR. For 250 of 260 patients, the subsequent required daily maintenance dose of phenprocoumon was also recorded. RESULTS: Both the necessary time and total dose required to attain target INR correlated significantly with BMI. The leaner the patient, the shorter the required time interval [BMI <22 (n=31), 5.48+/-2.49 days; BMI 22-25 (n=70), 6.09+/-2.40; BMI 25-30 (n=113), 6.76+/-3.61; BMI >30 (n=46), 8.50+/-5.75; p=0.001] and the lower the required dosage until the therapeutic range was achieved [BMI <22 (n=31), 23.8+/-12.1 mg; BMI 22-25 (n=70), 25.9+/-11.4 mg; BMI 25-30 (n=113), 29.6+/-25.2; BMI >30 (n=46), 35.8+/-19.7; p=0.027]. Overweight and waist circumference as a surrogate marker for abdominal fat were also associated significantly with these two parameters. Moreover, obesity was associated with a lower body-weight-adjusted maintenance dosage. All CYP2C9 genotypes that were tested failed to reveal an association with individual response variability. CONCLUSION: Patient obesity appears to directly correspond to the amount of phenprocoumon required during initiation of therapy. The CYP2C9 genotype was not shown to influence the necessary therapeutic dosage.

Quantification of aortic valve calcification using multislice spiral computed tomography: comparison with atomic absorption spectroscopy.

OBJECTIVES: Multislice spiral computed tomography (MSCT) allows the in vivo detection of valvular calcification. The aim of this study was to validate the quantification of aortic valve calcification (AVC) by MSCT with in vitro measurements by atomic absorption spectroscopy. METHODS: In 18 patients with severe aortic stenosis, 16 detector row MSCT (SOMATOM Sensation 16, Siemens, Forchheim, Germany with scan parameters as follows: 420 milliseconds tube rotation time, 12 x 0.75 mm collimation, tube voltage 120 KV) was performed before aortic valve replacement. Images were reconstructed at 60% of the RR interval with an effective slice thickness of 3 mm and a reconstruction increment of 2 mm. AVC was assessed using Agatston AVC score, mass AVC score, and volumetric AVC score. After valve replacement, the calcium content of the excised human stenotic aortic valves was determined in vitro using atomic absorption spectroscopy. RESULTS: The mean Agatston AVC score was 3,842 +/- 1,790, the mean volumetric AVC score was 3,061 +/- 1,406, and mass AVC score was 888 +/- 492 as quantified by MSCT. Atomic absorption spectroscopy showed a mean true calcification mass (Ca5(PO4)3OH) of 19 +/- 8 mass%. There was a significant correlation between in vivo AVC scores determined by MSCT and in vitro mean true calcification mass (r = 0.74, P = 0.0004 for mass AVC score, r = 0.79, P = 0.0001 for volumetric AVC score and r = 0.80, P = 0.0001 for Agatston AVC score) determined by atomic absorption spectroscopy. Linear regression analysis showed a significant association between the degree of hydroxyapatite (given in mass%) in the aortic valve and the degree of AVC (R = 0.74, F = 19.6, P = 0.0004 for mass AVC score, R = 0.80, F = 29.3, P = 0.0001 for Agatston AVC score and R = 0.79, F = 27.3, P = 0.0001 for volumetric AVC score) assessed by MSCT. CONCLUSION: MSCT allows accurate in vivo quantification of aortic valve calcifications.