Hans Joachim Schäfers

Aortic root numeric model: Annulus diameter prediction of effective height and coaptation in post–aortic valve repair

OBJECTIVEnThe aim of the present study was to determine the influence of the aortic annulus (AA) diameter in order to examine the performance metrics, such as maximum principal stress, strain energy density, coaptation area, and effective height in the aortic valve.nnnMETHODSnSix cases of aortic roots with an AA diameter of 20 and 30 mm were numerically modeled. The coaptation height and area were calculated from 3-dimensional fluid structure interaction models of the aortic valve and root. The structural model included flexible cusps in a compliant aortic root with material properties similar to the physiologic values. The fluid dynamics model included blood hemodynamics under physiologic diastolic pressures of the left ventricle and ascending aorta. Furthermore, zero flow was assumed for effective height calculations, similar to clinical measurements. In these no-flow models, the cusps were loaded with a transvalvular pressure decrease. All other parameters were identical to the fluid structure interaction models.nnnRESULTSnThe aortic valve models with an AA diameter range of 20 to 26 mm were fully closed, and those with an AA diameter range of 28 to 30 mm were only partially closed. Increasing the AA diameter from 20 to 30 mm decreased the averaged coaptation height and normalized cusp coaptation area from 3.3 to 0.3 mm and from 27% to 2.8%, respectively. Increasing the AA diameter from 20 to 30 mm decreased the effective height from 10.9 to 8.0 mm.nnnCONCLUSIONSnA decreased AA diameter increased the coaptation height and area, thereby improving the effective height during procedures, which could lead to increased coaptation and better valve performance.

Recurrence of obliterative bronchiolitis and determinants of outcome in 139 pulmonary retransplant recipients

An international series of pulmonary retransplantation was updated to identify the predictors of outcome and the prevalence and recurrence rate of obliterative bronchiolitis after operation. The study cohort included 139 patients who underwent retransplantation in 34 institutions in North America and Europe between 1985 and 1994. Eighty patients underwent retransplantation because of obliterative bronchiolitis, 34 because of acute graft failure, 13 because of intractable airway complications, 8 because of acute rejection, and 4 because of other indications. Survivors were followed up for a median of 630 days, with 48 patients alive at 1 year, 30 at 2 years, and 16 at 3 years after retransplantation. Actuarial survival was 65% +/- 4% at 1 month, 54% +/- 4% at 3 months, 45% +/- 4% at 1 year, 38% +/- 5% at 2 years, and 36% +/- 5% at 3 years; nonetheless, of 90-day postoperative survivors, 65% +/- 6% were alive 3 years after retransplantation. Life-table and univariate Cox analysis revealed that more recent year of retransplantation (p = 0.009), identical match of ABO blood group (p = 0.01), absence of a donor-recipient cytomegalovirus mismatch (p = 0.04), and being ambulatory immediately before retransplantation (p = 0.04) were associated with survival. By multivariate Cox analysis, being ambulatory before retransplantation was the most significant predictor of survival (p = 0.008), followed by reoperation in Europe (p = 0.044). Complete pulmonary function tests were done yearly in every survivor of retransplantation and bronchiolitis obliterans syndrome stages were assigned. Eleven percent of patients were in stage 3 at 1 year, 20% at 2 years, and 25% at 3 years after retransplantation. Values of forced expiratory volume in 1 second decreased from 1.89 +/- 0.13 L early after retransplantation to 1.80 +/- 0.15 L at 1 year and 1.54 +/- 0.16 L at 2 years (p = 0.006, year 2 versus baseline postoperative value). Most of this decrease occurred in patients who underwent retransplantation because of obliterative bronchiolitis, whereas the pulmonary function of patients who underwent retransplantation because of other conditions did not significantly change. We conclude that survival after pulmonary retransplantation is improving. Optimal results can be obtained in patients who are ambulatory before retransplantation. Compared with recent data after primary lung transplantation, bronchiolitis obliterans syndrome does not appear to recur in an accelerated manner after retransplantation. As long as early mortality as a result of infection can be minimized, pulmonary retransplantation appears to offer a reasonable option in highly selected patients.

Challenges in Infective Endocarditis

Infective endocarditis is defined by a focus of infection within the heart and is a feared disease across the field of cardiology. It is frequently acquired in the health care setting, and more than one-half of cases now occur in patients without known heart disease. Despite optimal care, mortality approaches 30% at 1 year. The challenges posed by infective endocarditis are significant. It is heterogeneous in etiology, clinical manifestations, and course. Staphylococcus aureus, which has become the predominant causative organism in the developed world, leads to an aggressive form ofxa0the disease, often in vulnerable or elderly patient populations. There is a lack of research infrastructure and funding, with few randomized controlled trials to guide practice. Longstanding controversies such as the timing of surgery or thexa0rolexa0ofxa0antibiotic prophylaxis have not been resolved. The present article reviews the challenges posed by infectivexa0endocarditis and outlines current and future strategies to limit its impact.

Linee guida per il trattamento delle valvulopatie (versione 2012). Task force congiunta per il trattamento delle valvulopatie della società europea di cardiologia (ESC) e dell'associazione europea di chirurgia cardiotoracica (EACTS)

Guidelines on the management of valvular heart disease (version 2012). The Joint Task Force on the Management of Valvular Heart Disease of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS)Authors/Task Force Members: Alec Vahanian (Chairperson) (France)*, Ottavio Alfieri (Chairperson)* (Italy), Felicita Andreotti (Italy), Manuel J. Antunes (Portugal), Gonzalo Barón-Esquivias (Spain), Helmut Baumgartner (Germany), Michael Andrew Borger (Germany), Thierry P. Carrel (Switzerland), Michele De Bonis (Italy), Arturo Evangelista (Spain), Volkmar Falk (Switzerland), Bernard Iung (France), Patrizio Lancellotti (Belgium), Luc Pierard (Belgium), Susanna Price (UK), Hans-Joachim Schäfers (Germany), Gerhard Schuler (Germany), Janina Stepinska (Poland), Karl Swedberg (Sweden), Johanna Takkenberg (The Netherlands), Ulrich Otto Von Oppell (UK), Stephan Windecker (Switzerland), Jose Luis Zamorano (Spain), Marian Zembala (Poland)

A Scoring-System for Angiographic Findings in Nonocclusive Mesenteric Ischemia (NOMI): Correlation with Clinical Risk Factors and its Predictive Value

AbstractPurposeThis study was designed to evaluate the clinical value of a standardized angiographic scoring system in patients with nonocclusive mesenteric ischemia (NOMI).nMethodsSixty-three consecutive patients (mean age: 73xa0±xa08xa0years) with suspect of NOMI after cardiac or major thoracic vessel surgery underwent catheter angiography of the superior mesenteric artery. Images were assessed by two experienced radiologists on consensus basis using a scoring system consisting of five categories, namely vessel morphology, reflux of contrast medium into the aorta, contrasting and distension of the intestine, as well as the time to portal vein filling. These were correlated to previously published risk factors of NOMI and outcome data.ResultsThe most significant correlation was found between the vessel morphology and death (pxa0<xa00.001) as well as reflux of contrast medium into the aorta and death (pxa0=xa00.005). Significant correlation was found between delayed portal vein filling and preoperative statin administration (pxa0=xa00.011), previous stroke (pxa0=xa00.033), and renal insufficiency (pxa0=xa00.043). Reflux of contrast medium correlated significantly with serum lactate >10xa0mmol/L (pxa0=xa00.046). The overall angiographic score correlated with death (pxa0=xa00.017) and renal insufficiency (pxa0=xa00.02). The ROC-analysis revealed that a score of ≥3.5 allows for identifying patients with increased perioperative mortality with a sensitivity of 85.7xa0% and a specificity of 49xa0%. With the use of a simplified score (vessel morphology, reflux of contrast medium into the aorta, and time to portal vein filling), specificity was increased to 71.4xa0%.ConclusionsThe applied scoring system allows standardized interpretation of angiographic findings in NOMI patients. Beyond that the score seems to correlate well with risk factors of NOMI and outcome.

Aortic root numeric model: Correlation between intraoperative effective height and diastolic coaptation

Effective height (hE) is a geometric parameter that can be measured during procedures and has been suggested as a predictor of valve performance. Few studies have suggested that the hE can be increased only by cusp intervention. In a previous study, we used 3dimensional numeric models of compliant aortic valves and roots and studied the influence of aortic annulus diameter. Although we found a correlation between the hE and the coaptation height (hC), we did not check the influence of the cusp size on this correlation. In this communication, we expand on our previous study and determine the correlation between hE and hC on the ba-

The Novel Two-Dimensional Strain Reflects Improvement and Remodeling of Left-Ventricular Function Better Than Conventional Echocardiographic Parameters After Aortic Valve Repair in Pediatric Patients

We aimed to evaluate the outcome and regional and global left-ventricular (LV) function after aortic valve repair in children with congenital aortic valve disease. Thirty-two consecutive patients with a mean age of 12.62xa0years (4xa0months to 18xa0years) undergoing aortic valve repair due to valve stenosis (AS group, nxa0=xa021) or aortic regurgitation (AR group, nxa0=xa011) were studied during a follow-up period of 12xa0months regarding change and adaptation of myocardial function using conventional and novel echocardiographic methods, including two-dimensional (2D) strain echocardiogram. Conventional and 2D strain echocardiographic studies were performed and analyzed off-line using commercially available software (EchoPac 6.1.0, GE). Peak aortic valve gradient decreased from 62.04xa0±xa030.34xa0mmHg before surgery to 22.80xa0±xa014.13xa0mmHg 2xa0weeks after surgery and to 35.73xa0±xa022.11xa0mmHg 12xa0months after surgery (pxa0=xa00.01). The degree of AR decreased significantly to grade 0 in 20 children and to grade I in 12. There was a significant decrease of thickness of the interventricular septum (IVS) and posterior wall resulting in improvement of LV mass index (pxa0=xa00.007, pxa0=xa00.043, and pxa0=xa00.001, respectively). Significant decrease of myocardial thickness was found, especially in the IVS, in the AS group (pxa0=xa00.008), and a significant decrease in LV end-diastolic dimension (EDD) was found in the AR group (pxa0=xa00.007). 2D strain analysis showed that global peak strain, global systolic strain rate, and global early diastolic strain rates improved significantly for all patients during the study period after aortic valve repair (pxa0<xa00.001, pxa0=xa00.037, and pxa0=xa00.018, respectively). The global strain and strain rates correlated significantly to IVS thickness (rxa0=xa00.002 and rxa0=xa00.003, respectively), LV mass index (rxa0=xa00.02 and rxa0=xa00.015, respectively), and EDD (rxa0=xa00.26 and rxa0=xa00.005, respectively). Aortic valve repair surgery in pediatric patients results in improvement of global and regional systolic and diastolic LV parameters, which was better shown by 2D strain parameters rather than conventional echocardiographic parameters.

Presepsin (sCD14-ST) Is a Novel Marker for Risk Stratification in Cardiac Surgery Patients

Background: Presepsin (soluble cluster-of-differentiation 14 subtype [sCD14-ST]) is a humoral risk stratification marker for systemic inflammatory response syndrome and sepsis. It remains unknown whether presepsin can be used to stratify risk in elective cardiac surgery. The authors therefore determined the usefulness of presepsin for risk stratification in patients having elective cardiac surgery. Methods: Eight hundred fifty-six cardiac surgical patients were prospectively studied. Preoperative plasma concentrations of presepsin, procalcitonin, N-terminal pro–hormone natriuretic peptide, cystatin C, and the additive European System of Cardiac Operative Risk Evaluation 2 were compared to mortality at 30 days (primary outcome), 6 months, and 2 yr. Discrimination was assessed with C statistic. Logistic regression analysis was used to calculate univariable and multivariable odds ratios. Results: Thirty-day mortality was 3.2%, 6-month mortality was 6.1%, and 2-yr mortality was 10.4% across the population. Median preoperative presepsin concentrations were significantly greater in 30-day nonsurvivors than in survivors: 842 pg/ml (interquartile range, 306 to 1,246) versus 160 pg/ml (interquartile range, 122 to 234); difference, 167 pg/ml (interquartile range, 92 to 301; P < 0.001). The results were similar for 6-month and 2-yr mortality. Compared to the European System of Cardiac Operative Risk Evaluation 2, presepsin concentration provided better discrimination for postoperative mortality at all follow-up periods, including 30 days (C statistic 0.88 vs. 0.74), 6 months (0.87 vs. 0.76), and 2 yr (0.81 vs. 0.74). Presepsin also provided better discrimination than cystatin C, N-terminal pro–hormone natriuretic peptide, or procalcitonin. Elevated presepsin remained an independent risk predictor after adjustment for potential confounding factors. Conclusions: Elevated preoperative plasma presepsin concentration is an independent predictor of postoperative mortality in elective cardiac surgery patients and is a stronger predictor than several other commonly used assessments.

Use of argatroban: experiences in continuous renal replacement therapy in critically ill patients after cardiac surgery.

OBJECTIVESnAcute kidney injury requiring renal replacement therapy (RRT) is a common complication after cardiac surgery, complicated by suspected or proven heparin-induced thrombocytopenia (type II). The present study evaluated the use of argatroban as an anticoagulant during continuous RRT in the early period after cardiac surgery. Argatroban was compared with unfractionated heparin (UH) with respect to bleeding complications and the effectiveness of anticoagulation.nnnMETHODSnPatients requiring RRT after cardiac surgery from March 2007 to June 2009 were identified. The effectiveness of anticoagulation was measured indirectly by the duration of dialysis filter use. Bleeding was defined as clinical signs of blood loss or the need for transfusion.nnnRESULTSnOf 94 patients, 41 received argatroban, 27 UH, and 26 required conversion from UH to argatroban. In all 3 subgroups, RRT was begun within a median postoperative period of 2.0 days. Similar levels of anticoagulation were achieved with the duration of the circuit and filter changed an average of 1.1 times daily during RRT. Liver function was comparable in all patients. Neither clinically relevant signs of bleeding nor significant differences in the hemoglobin levels or a requirement for transfusion were noted. However, the Simplified Acute Physiology Score II values during dialysis and mortality were significantly greater in the patients initially receiving argatroban compared with those who received UH alone (54 ± 2 vs 43 ± 3, P < .001; 71% vs 44%, P = .04).nnnCONCLUSIONSnArgatroban can provide effective anticoagulation in postoperative cardiac patients receiving continuous RRT. Close monitoring and dose titration resulted in a comparable risk of bleeding for anticoagulation with both argatroban and heparin, regardless of the disease severity or impaired hepatic function.

Aortic annuloplasty: The panacea of valve-preserving aortic replacement?

From the Department of Thoracic and Cardiovascular Surgery, Saarland University Medical Center, Homburg/ Saar, Germany. Disclosures: Author has nothing to disclose with regard to commercial support. Received for publication Jan 10, 2017; accepted for publication Jan 12, 2017. Address for reprints: Hans-Joachim Sch€afers, MD, Department of Thoracic and Cardiovascular Surgery, Saarland University Medical Center, Homburg/Saar, Germany (E-mail: h-j.schaefers@uks.eu). J Thorac Cardiovasc Surg 2017;-:1-2 0022-5223/