Left ventricular support adjustment to aortic valve opening with analysis of exercise capacity

Background LVAD speed adjustment according to a functioning aortic valve has hypothetic advantages but could lead to submaximal support. The consequences of an open aortic valve policy on exercise capacity and hemodynamics have not yet been investigated systematically. Methods Ambulatory patients under LVAD support (INCOR®, Berlin Heart, mean support time 465 ± 257 days, average flow 4.0 ± 0.3 L/min) adjusted to maintain a near normal aortic valve function underwent maximal cardiopulmonary exercise testing (CPET) and right heart catheterization (RHC) at rest and during constant work rate exercise (20 Watt). Results Although patients (n = 8, mean age 45 ± 13 years) were in NYHA class 2, maximum work-load and peak oxygen uptake on CPET were markedly reduced with 69 ± 13 Watts (35% predicted) and 12 ± 2 mL/min/kg (38% predicted), respectively. All patients showed a typical cardiac limitation pattern and severe ventilatory inefficiency with a slope of ventilation to carbon dioxide output of 42 ± 12. On RHC, patients showed an exercise-induced increase of mean pulmonary artery pressure (from 16 ± 2.4 to 27 ± 2.8 mmHg, p < 0.001), pulmonary artery wedge pressure (from 9 ± 3.3 to 17 ± 5.3 mmHg, p = 0.01), and cardiac output (from 4.7 ± 0.5 to 6.2 ± 1.0 L/min, p = 0.008) with a corresponding slight increase of pulmonary vascular resistance (from 117 ± 35.4 to 125 ± 35.1 dyn*sec*cm−5, p = 0.58) and a decrease of mixed venous oxygen saturation (from 58 ± 6 to 32 ± 9%, p < 0.001). Conclusion An open aortic valve strategy leads to impaired exercise capacity and hemodynamics, which is not reflected by NYHA-class. Unknown compensatory mechanisms can be suspected. Further studies comparing higher vs. lower support are needed for optimization of LVAD adjustment strategies

Enhanced Cardiac CaMKII Oxidation and CaMKII-Dependent SR Ca Leak in Patients with Sleep-Disordered Breathing

Background: Sleep-disordered breathing (SDB) is associated with increased oxidant generation. Oxidized Ca/calmodulin kinase II (CaMKII) can contribute to atrial arrhythmias by the stimulation of sarcoplasmic reticulum Ca release events, i.e., Ca sparks. Methods: We prospectively enrolled 39 patients undergoing cardiac surgery to screen for SDB and collected right atrial appendage biopsies. Results: SDB was diagnosed in 14 patients (36%). SDB patients had significantly increased levels of oxidized and activated CaMKII (assessed by Western blotting/specific pulldown). Moreover, SDB patients showed a significant increase in Ca spark frequency (CaSpF measured by confocal microscopy) compared with control subjects. CaSpF was 3.58 ± 0.75 (SDB) vs. 2.49 ± 0.84 (no SDB) 1/100 µm−1s−1 (p < 0.05). In linear multivariable regression models, SDB severity was independently associated with increased CaSpF (B [95%CI]: 0.05 [0.03; 0.07], p < 0.001) after adjusting for important comorbidities. Interestingly, 30 min exposure to the CaMKII inhibitor autocamtide-2 related autoinhibitory peptide normalized the increased CaSpF and eliminated the association between SDB and CaSpF (B [95%CI]: 0.01 [−0.1; 0.03], p = 0.387). Conclusions: Patients with SDB have increased CaMKII oxidation/activation and increased CaMKII-dependent CaSpF in the atrial myocardium, independent of major clinical confounders, which may be a novel target for treatment of atrial arrhythmias in SDB

Influence of hydroxy-methylglutharyl-coA-reductase-inhibitor atorvastatine on chronic renal allograft rejection in rats

Tierexperimentelle Untersuchung bezüglich chronische Transplantatnephropathie beziehungsweise deren fragliche Verminderung durch Gabe des Hydroxy-Methylglutharyl-Coenzym-A-Inhibitors Atorvastatin nach Nierentransplantation bei Ratten(Fisher344/Lewis); Vergleich von drei Versuchsgruppen-jeweils acht Versuchstiere-bezüglich Gewicht, Diuresevolumen, Serum-Kreatinin, Serum-Harnstoff, Kreatinin-Clearance und Proteinurie nach 30, 60, 90 und 120 Tagen Versuchslaufzeit; akute/chronische Abstoßungsreaktion, antigen-abhängige/-unabhängige Faktoren, direkte/indirekte T-Lymphozyten-Aktivierung und Kostimulation durch Zelloberflächen-Proteine, mikrochirurgischer Eingriff der Nierentranplantation bei Ratten.Study about chronic renal allograft rejection and attenuation by hydroxy-methylglutharyl-coA-inhibitor atorvastatine in rats (fisher344/lewis). comparing of three study groups-eight animals each group-in weight, diuresis volume, creatinine, urea, creatinine-clearance and proteinuria 30, 60, 90 and 120 days after surgery. acute/chronic allograft rejection, immunologic/non-immunologic factors, mediate/immediate T-cell-activation and co-stimulation by cell surface proteins, microsurgical kidney transplantation in rats

Pericardiectomy for Constrictive Pericarditis: An Institution's 21 Years Experience

Background The aim of this retrospective study was to evaluate our experience with the surgical pericardiectomy procedure for patients suffering from isolated severe constrictive pericarditis. Methods From 1995 to 2016, 39 patients underwent isolated pericardiectomy for constrictive pericarditis. Fifteen patients were excluded because of concomitant surgery. There were 31 male ( 79.5%) patients and 8 female ( 20.5%) patients, 28 to 76 years old ( mean, 56.6 13.6 years). The underlying etiologies were idiopathic pericarditis ( 74.5%), infection ( 10%), rheumatic disorders ( 8%), status post cardiac surgery ( 2.5%), tuberculosis ( 2.5%), and status post mediastinal irradiation ( 2.5%). Results Pericardiectomy was performed through midline sternotomy in all cases. Sixteen patients ( 41%) underwent pericardiectomy electively employing cardiopulmonary bypass with the heart beating, and 23 patients ( 59%) had surgery without extracorporeal circulation ( ECC). The overall 30- day mortality rate was 50% if cardiopulmonary bypass was used ( 13.8% since 2007). If surgery was performed without a heart- lung machine, mortality was 0%. On- pump patients had a significantly longer intensive care unit ( ICU) stay ( 12 9 vs. 4 4 days, p 1/4 0.013). Likewise, the duration of mechanical ventilation was much longer ( 171 246 vs. 21 40 hours, p 1/4 0.04). The hospital stay was comparable with 28 10 and 24 18 days ( p 1/4 0.21). Conclusion The present study demonstrates that pericardiectomy, without the use of cardiopulmonary bypass as treatment for constrictive pericarditis, is a safe procedure with an excellent outcome in critically ill patients

Impact of coronary angiography early after CABG for suspected postoperative myocardial ischemia

Abstract Background The incidence of perioperative myocardial infarction is reported to 2–8%. The aim of the study (retrospectively registered) was to evaluate whether control coronary angiography after surgery is useful in case of suspected postoperative myocardial ischemia. Methods All patients who demonstrated signs of myocardial ischemia post CABG and underwent coronary angiography from 6/2008 to 06/2015 were retrospectively analyzed. Myocardial ischemia post CABG was defined as an increase of CK/CK-MB, occasionally associated with arrhythmias or low output syndrome. Results Overall, 108 patients (age 66 ± 9 years) demonstrated signs of myocardial ischemia post CABG and underwent coronary angiography corresponding to an incidence of 2.2%. Of them, 70 patients (65%) demonstrated graft pathologies. A therapeutic consequence was drawn in 62 Patients (57%), which consisted of redo surgery in 10 patients (9%) and PCI with stent placement in 52 patients (48%). Of the remaining 46 patients, 29 patients showed intact bypass grafts (27%), whereas 17 patients had minor pathologies (16%). Demographic data including the extent of the coronary artery disease, urgency of operation, comorbidities, EuroScore, surgical technique, postoperative lab tests and transfusion requirements were comparable among the groups. Redo surgery patients had prior PCI in 33% of patients, which was much higher than in the other groups. Patients with reintervention had a 30d-mortality rate of 13%, conservatively treated patients only 2.2%. Mortality was highest after redo surgery with 25%. Conclusions Postoperative coronary angiography is a useful tool with a significant therapeutic value. Pathological findings mandate further revascularization therapy in roughly half of the patients. PCI is a safe choice in the majority of patients, redo surgery is much less indicated

Postoperative acute respiratory dysfunction and the influence of antibiotics after acute type A aortic dissection surgery: A retrospective analysis

Objectives Surgery for acute type A aortic dissection is associated with several perioperative complications, such as acute respiratory dysfunction (ARD). The aim of this study was to investigate perioperative risk factors involved in the development of ARD and whether antibiotic treatment has an impact. Methods 243 patients underwent surgery for acute type A aortic dissection between 2008 and 2017. The patients were retrospectively divided into the ARD and NON-ARD group. ARD was defined as PaO2/FiO2 ≤ 200 mmHg (PF ratio) within 48 hours after surgery. All patients received either narrow- or broad-spectrum antibiotics. Results After the exclusion of 42 patients, 201 patients were analyzed. The PF ratio of the ARD group was significantly lower than of the NON-ARD group within the first 7 days. ARD patients (n = 111) were significantly older (p = .031) and had a higher body mass index (BMI) (p = .017). ARD patients required longer postoperative ventilation (2493 vs. 4695 [min], p = .006) and spent more days in the intensive care unit (7.0 vs. 8.9 [days], p = .043) compared to NON-ARD. The mortality was significantly lower for ARD than for NON-ARD patients (p = .030). The incidence of pneumonia was independent of the antibiotic treatment regime (p = .391). Renal and neurological complication rate was higher in patients treated with broad-spectrum antibiotic. Conclusion ARD is the main complication (55%) that occurs approximately 24 hours after surgery for acute type A aortic dissection. The preoperative risk factors for ARD were higher age and increased BMI. Patients on broad-spectrum antibiotics did not show an improved postoperative outcome compared to patients with narrow-spectrum antibiotics

Patients under Psychiatric Medication Undergoing Cardiac Surgery Have a Higher Risk for Adverse Events

Objective The percentage of patients undergoing cardiac surgery under some sort of psychiatric medication (PM) is not negligible. Thus, this study aimed to evaluate a possible impact of preoperative PM on the outcome after cardiac surgery. Methods A matched case-control study was conducted by including all patients who underwent myocardial revascularization and/or surgical valve operation in our institution from December 2008 till February 2011 by chart review and institutional quality assurance database (QS) analysis. Results Out of 1,949 patients included, 184 patients (9%) were identified with PM medication (group A). A control group matched for logistic EuroSCORE II, ejection fraction and age was generated (group C). Patients with PM were in mean significantly longer on the intensive care unit (A: 4.94 days; 95% confidence interval (CI), 3.9-5.9 days vs. C: 3.24 days; CI, 2.84-3.64 days; p = 0.003), had longermechanical ventilation times (A: 36.70 hours; CI, 19.81-53.59 hours vs. C: 20.14 hours; CI, 14.61-25.68 hours; p = 0.258), and significantly more episodes of respiratory insufficiencies (A: 31 episodes [17%] vs. C: 17 episodes [9%]; p = 0.002). Regression analysis revealed preoperative PM as a significant risk factor for respiratory insufficiency (odds ratio: 1.99, CI: 1.0-3.74; p = 0.04). Chest tube drainage (A: 690 mL, CI: 571-808 mL vs. C: 690 mL; CI: 496-884 mL, p = 0.53) and the total amount of red blood cell transfusion units were similar (A: 1.69 units; CI: 1.21-2.18 units vs. C: 1.50 units; CI: 1.04-1.96 units; p = 0.37). Sternal dehiscence requiring sternal refixation was significantly more frequent in A (12 patients [7%] vs. C: 2 patients [1%]; odds ratio: 6.3, CI: 1.4-28.7; p = 0.01). The 30-day mortality was similar in both groups (A: 6 patients [3%] vs. C: 4 patients [2%]; odds ratio: 1.5; CI: 0.4-5.4; p = 0.5); however, the 100-daymortality was near significantly higher in group A (A: 14 patients (8%) vs. C: 6 patients (3%); odds ratio: 2.4, CI: 0.9-6.5, p =0.057). Conclusion Patients with preoperative PM developed complications more frequently compared with a matched control group. The underlying multifactorial mechanisms remain unclear. Patients under PM need to be identified and particular care including optimal pre-and postoperative psychiatric assistance is recommended

Brain Death Induction in Mice Using Intra-Arterial Blood Pressure Monitoring and Ventilation via Tracheostomy

While both living donation and donation after circulatory death provide alternative opportunities for organ transplantation, donation after donor brain death (BD) still represents the major source for solid transplants. Unfortunately, the irreversible loss of brain function is known to induce multiple pathophysiological changes, including hemodynamic as well as hormonal modifications, finally leading to a systemic inflammatory response. Models that allow a systematic investigation of these effects in vivo are scarce. We present a murine model of BD induction, which could aid investigations into the devastating effects of BD on allograft quality. After implementing intra-arterial blood pressure measurement via the common carotid artery and reliable ventilation via a tracheostomy, BD is induced by steadily increasing intracranial pressure using a balloon catheter. Four hours after BD induction, organs may be harvested for analysis or for further transplantation procedures. Our strategy enables the comprehensive analysis of donor BD in a murine model, therefore allowing an in-depth understanding of BD-related effects in solid organ transplantation and potentially paving the way to optimized organ preconditioning

Sleep-disordered breathing is associated with disturbed cardiac repolarization in patients with a coronary artery bypass graft surgery

Background: The development of malignant ventricular arrhythmias due to abnormal cardiac repolarization is a major complication after coronary artery bypass graft surgery (CABG). Sleep-disordered breathing (SDB) is linked to prolonged cardiac repolarization in non-surgical patients. This study evaluates cardiac repolarization in patients with and without SDB who underwent CABG. Methods: 100 patients who had received CABG (84% men, age 68 +/- 10 years, body-mass-index [BMI] 28.7 +/- 4.2 kg/m(2)) were retrospectively evaluated. Polygraphy was recorded the night before CABG. SDB was defined as an apnea-hypopnea index (AHI) of >= 15/h and differentiated into central (CSA) and obstructive (OSA) sleep apnea. Cardiac repolarizationwas assessed by means of T-peak-to-end (TpTe) and QTc-intervals and TpTe/QT-ratios derived from 12-lead electrocardiography (ECG). Results: 37% of patients had SDB, 14% CSA and 23% OSA. Before CABG, patients with CSA and OSA had longer TpTe intervals than those without SDB (TpTe: CSA 100 +/- 26 vs. OSA 97 +/- 19 vs. no SDB 85 +/- 14 ms, p = 0.013). QTc intervals and TpTe/QT ratios differed between the two groups (QTc: 444 +/- 54 vs. 462 +/- 36 vs. 421 +/- 32 ms, p < 0.001; TpTe/QT ratio: 0.24 +/- 0.04 vs. 0.23 +/- 0.05 vs. 0.21 +/- 0.03, p = 0.045). SDB was associated with abnormal cardiac repolarization independent of known risk factors for cardiac arrhythmias, such as age, sex, BMI, N-terminal-pro-brain-natriuretic-peptide (NT-proBNP), and heart failure (TpTe: B-coefficient [95%-CI]: 16.0, [7.6-24.3], p < 0.001; QTc: 27.2 [9.3-45.1], p = 0.003; TpTe/QT ratio: 2.9 [1.2-4.6], p < 0.001). Conclusion: Independent of known risk factors for cardiac arrhythmias, SDB was significantly associated with abnormal cardiac repolarization before CABG. Data suggest that SDB may contribute to an increased risk of ventricular arrhythmias after CABG. (c) 2018 Elsevier B.V. All rights reserved