Primary hemostatic disorders drive early and late major bleedings of patients with atrial fibrillation after transcatheter aortic valve replacement

Introduction

Patients with atrial fibrillation (AF) are likely to have multiple co-morbidities and receive anticoagulants after TAVR, which lead to a poor prognosis including bleeding events. Closure time adenosine diphosphate (CT-ADP) is a primary hemostasis point-of-care test used as a surrogate marker of high molecular weight (HMW) multimers defect of Von Willebrand factor (VWF). Our prior studies suggest that prolongation of CT-ADP (>180 seconds) after TAVR is a major determinant of early and late major/life-threatening bleeding complications (MLBCs).

Purpose

To evaluate the impact of post-procedural CT-ADP >180sec on bleeding events in AF patients.

Methods

We included 878 patients from our prospective TAVR registry between 2010 and 2019. Bleeding complications were assessed according to the VARC-2 (Valve Academic Research Consortium-2) criteria. Major adverse cardiac and cerebrovascular events (MACCE) was defined as a composite of all-cause death, myocardial infarction, stroke, and heart failure hospitalization within 1-year after TAVR. Ongoing primary haemostasis disorder was defined by post-procedure CT-ADP >180sec. Primary endpoint was the occurrence of MLBCs during the first year and the second endpoint was 1-year MACCE.

Results

Patients with AF had a higher incidence of all-cause mortality (15% vs. 8%, p=0.002), MACCE (29% vs. 20%, p=0.002), and MLBCs (20% vs. 12%, p=0.001) within 1-year compared to non-AF patients. When the cohort was split into 4 subgroups according to AF and CT-ADP >180sec, patients with AF and CT-ADP >180sec had the highest risk of MLBCs (log-rank test; p<0.001) (Figure). Multivariate Cox regression analysis confirmed that the patients with AF and CT-ADP >180sec had 4.6-fold higher risk of MLBCs within 1 year compared to non-AF patients with CT-ADP ≤180sec (hazard ratio: 4.60; 95% confidence interval: 2.18 - 9.68; p<0.001).

Conclusion

Among TAVR patients, AF with post-procedural CT-ADP >180 sec was identified as a strong independent predictor of MLBCs at 1-year follow-up. Our study suggest that persistent primary haemostasis disorders contribute to a higher risk of bleeding events particularly in AF patients and may be considered for a tailored and risk-adjusted antithrombotic therapy after TAVR.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Dr Matsushita received a grant from Edwards Lifesciences.

[Comparison of the Outcomes of Revision Anterior Cruciate Ligament Reconstruction Using Cadaverous BTB Graft with the Outcomes of Primary ACL Reconstruction with Filtering out the Effects of Age and Sex]

PURPOSE OF THE STUDY Evaluation of the success rate of revision ACL reconstruction using the cadaverous BTB allogeneic graft and comparison of the outcomes achieved with the data of patients after the primary ACL reconstruction using the autologous BTB graft with filtering out the potential effect of diversity of the groups of patients as concerns sex and age. MATERIAL AND METHODS The evaluated outcomes of 34 patients operated in the period 2004-2017, i.e. with the minimum follow-up period of three years, were compared with the outcomes of 34 patients selected individually so that in pairs the age and sex are identical - 10 women and 24 men in the range of age from 20 to 44 years, with the median of 29 years at the time of surgery. The assessment and comparison of the outcomes achieved are done according to the Lysholm and Tegner scores. RESULTS The mean Lysholm score of the patients after the revision ACL reconstruction using the cadaverous BTB allograft achieved 54.7 points preoperatively, 72.3 points at the 1-year follow-up and 77.4 points at the 3-year follow-up. The Tegner score at the time of full performance before the injury was 7.7 points, whereas it was 5.8 points after the injury and 6.5 points three years after the surgery. In the group of patients after the primary ACL reconstruction using the autologous BTB graft, the Lysholm score was 64.4 points preoperatively, 85.1 points one year postoperatively and 88.2 points three years postoperatively. The results according to the Tegner score achieved by the primary control group at respective follow-up periods were 6.7 points, 5.1 points and 6.2 points respectively. DISCUSSION The increase in the number of performed ACL reconstructions leads also to an increase in the number of revision surgeries. This trend is also fuelled by the change in the lifestyle, the shift in age-related indication criteria for surgery, and other factors. The realistic expectations regarding the outcome of the revision ACL reconstruction shall take into account the effect of multiple insults that the knee must withstand. Even though subjective improvement of the knee condition is usually experienced postoperatively, the achieved outcomes tend to be less positive than in primary reconstructions. The return to the original pre-injury level of sports activities is achieved less frequently after revision surgeries. CONCLUSIONS The revision surgery of ACL rupture using the cadaverous BTB graft is a safe and reliable technique. It has a potential to improve the subjective satisfaction of the patient, nonetheless the mean postoperative Lysholm score is not so high as that achieved in patients after primary ACL reconstruction. Key words: anterior cruciate ligament, revision ACL reconstruction, cadaverous BTB graft, ACL graft rerupture.

P2Y12 inhibition by clopidogrel increases adverse clinical outcomes in patients undergoing transcatheter aortic valve replacement

Introduction

Current recommendations support short-term dual antiplatelet therapy (DAPT) for patients undergoing transcatheter aortic valve replacement (TAVR) despite no relevant study exploring the extent of platelet inhibition by clopidogrel.

Purpose

To assess whether P2Y12 inhibition by clopidogrel as evaluated by vasodilator-stimulated phosphoprotein flow cytometry test (VASP-FCT) impacts 1-year clinical outcomes in patients undergoing TAVR.

Methods

Patients were included in a prospective registry between February 2010 and May 2019. VASP-FCT was assessed 24h after the procedure. Responder to clopidogrel was defined by a platelet reactivity index ≤50%.

Results

Of 640 patients who underwent TAVR with preprocedural clopidogrel therapy, we enrolled 491 patients for whom VASP data were available. Responders were identified in 22% (n=110) of patients and low responders were 78% (n=381) of patients. Low body mass index, active cancer, and clopidogrel on admission were found to be independent predictors of responder. Mean transaortic pressure gradient was lower in the responder group at 1-month post-TAVR (9.9±4.4 mmHg vs. 11.2±5.8 mmHg, p=0.03) but was similar at 1-year (11.5±6.2 mmHg vs. 11.9±7.4 mmHg, p=0.74). By multivariate Cox regression analysis, patients responding to clopidogrel (hazard ratio [HR]: 2.19; 95% confidence interval [CI]: 1.04 to 3.64; p=0.04), prior PCI (HR: 2.12; 95% CI: 1.07 to 4.37; p=0.03), and mean transaortic pressure gradient at baseline (HR: 0.07; 95% CI: 0.01 to 0.70; p=0.02) were identified as independent predictors of 1-year adverse clinical outcomes, including all-cause death, myocardial infarction, stroke, and heart failure hospitalization.

Conclusions

Appropriate P2Y12 inhibition by clopidogrel is a major determinant of adverse clinical events after TAVR. In sum, the present data challenges the need of DAPT as a standard therapy during TAVR.

Figure 1

Funding Acknowledgement

Type of funding source: None

Predictive impact of PVL assessments on clinical outcomes in patients undergoing TAVR

Introduction

Paravalvular leakage (PVL) following transcatheter aortic valve replacement (TAVR) is associated with greater mortality. In clinical practice, determining PVL severity after TAVR remains challenging and often requires multiparametric assessment.

Purpose

This study sought to evaluate the respective value of various modalities of PVL assessments, including transthoracic echocardiography (TTE), cine-angiography, aortic regurgitation index (ARI), and closure time with adenosine diphosphate (CT-ADP), in the prediction of adverse clinical outcomes.

Methods

We included 1044 patients from our prospective TAVR registry between February 2010 and May 2019. Major adverse cardiac and cerebrovascular events (MACCE) was defined as a composite of all-cause death, myocardial infarction, stroke, and heart failure hospitalization within 1-year. Established cutoff values of ARI (<25) and CT-ADP (>180 sec) were used to assess the presence of PVL after TAVR.

Results

Moderate to severe PVL occurred in 14.2% and 5.2% of patients as measured by TTE and angiography. The rate of patients with ARI <25 and CT-ADP >180 sec were 36.5% and 24.9%, respectively. Among the four modalities, PVL evaluated by angiography predicted poorer clinical outcomes (Log rank test; p=0.001), whereas TTE, ARI <25, and CT-ADP >180 sec were not associated with 1-year MACCE. By multivariate Cox regression analysis, moderate to severe PVL by angiography was an independent predictor of 1-year MACCE (hazard ratio: 1.96; 95% confidence interval: 1.22–3.00; p=0.007).

Conclusions

Paravalvular leakage measured by angiography was evidenced as the most meaningful modality in the prediction of adverse clinical outcomes. Future multicenter studies are warranted to ensure these findings in the current TAVR era.

Figure 1

Funding Acknowledgement

Type of funding source: None

Incomplete recovery of takotsubo cardiomyopathy is a major determinant of cardiovascular mortality

Introduction

Although there is an apparent rapid and spontaneous recovery of left ventricular ejection fraction (LVEF) in patients with takotsubo cardiomyopathy, recent studies have demonstrated the long-lasting functional impairment in those patients.

Purpose

We sought to evaluate the predictors of incomplete recovery in chronic phase and its impact on cardiovascular mortality after takotsubo cardiomyopathy.

Methods

Patients with takotsubo cardiomyopathy between 2008 and 2018 were retrospectively enrolled in three different institutions. Takotsubo cardiomyopathy was diagnosed according to the European Society of Cardiology Heart Failure Association criteria. After exclusion of in-hospital deaths, 407 patients were split into 2 subgroups according whether their LVEF were >50% (recovery group; n=333), or ≤50% (incomplete recovery group; n=74) at follow-up. The primary endpoint was the impact of incomplete recovery on cardiovascular mortality.

Results

Patients with incomplete recovery were more likely to be male, to have dementia, pacemaker, and supraventricular arrhythmia. C-reactive protein (CRP) levels on admission, at peak, and at discharge were significantly higher in patients with incomplete recovery. By multivariate logistic regression analysis, lower EF at discharge (odds ratio [OR]: 0.91; 95% confidence interval [CI]: 0.88 to 0.95; p<0.001) and higher CRP levels (OR: 5.56; 95% CI: 1.86 to 16.61; p<0.001) were independent predictors of incomplete recovery at follow-up. The cumulative event-free survival rate according to cardiovascular death was significantly lower in the incomplete recovery group (p<0.001; log-rank test).

Conclusions

We demonstrate that incomplete recovery after takotsubo cardiomyopathy is characterized by a residual systemic inflammation and an increased cardiac mortality at follow-up. Altogether, our findings underline patients with persistent inflammation as a high-risk subgroup, to target in future clinical trials with specific therapies to attenuate inflammation.

Funding Acknowledgement

Type of funding source: None

P5441Ventricular dysfunction and fibrosis precedes atrial conduction defects in JDP2 overexpression mice

Introduction

JDP2 (Jun Dimerization Protein 2) was recently characterized as potential prognostic marker for progression of heart failure after myocardial infarction. Furthermore, persistent cardiac-specific JDP2 overexpression provokes ventricular dysfunction, atrial dilatation and atrial fibrillation.

Purpose

In this study we investigated, if ventricular dysfunction is predisposed to atrial fibrillation. Therefore, we analyzed ventricular function in mice with 1 and 5 weeks of JDP2 overexpression and compared gene expression in ventricular and atrial tissues at these time points.

Methods

JDP2 expression was under control of a Tet-off system. Therefore, JDP2 overexpression was started by withdrawal of doxycycline diet in 4-week-old mice. After 1 or 5 weeks, cardiac function was determined by echocardiography and ECG. mRNA expression was analyzed by real-time RT-PCR and protein expression in western blots.

Results

After 1 or 5 weeks, JDP2 mRNA levels were increased in ventricular and atrial tissues of JDP2 mice. Already after 1 week ventricular dysfunction emerged in JDP2 mice: Ejection fraction decreased from 64.6±10.4% in WT to 58.8±9.3% in JDP2 mice, fractional shortening from 38.3±7.9% in WT to 27.4±4.8% in JDP -mice, and cardiac output from 23.0±4.7 ml/min in WT to 19.4±3.3 ml/min in JDP2 mice (n=11–16, p<0.05). In ventricular tissues, elastin mRNA expression increased, and the calcium handling protein SERCA decreased within one week of JDP2 overexpression (n=6, p<0.05 vs. WT). After 5 weeks of JDP2 overexpression ventricular dysfunction became even stronger with a cardiac output of 13.6±2.5 ml/min (n=11, p<0.05 vs. WT). Still reduction in SERCA protein was observed, and increased mRNA levels of fibrotic marker genes were detected, as well as contractile function of isolated cardiomyocytes of JDP2 mice continued to decline. In atrial tissue, besides the 3.6 times increase of JDP2 mRNA, no changes could be detected within one week. In addition, ECG recordings over 30 minutes on awake mice did not show any abnormalities after one week of JDP2-overexpression. Atrial dilatation became evident only after 5 weeks of JDP2 overexpression. ECG-recordings revealed prolonged PR-intervals (34.6±3.9 ms in JDP2-mice vs. 30.2±7.0 ms in WT) and broadened QRS-complexes (15.8±2.8 ms in JDP2 mice vs. 13.9±1.7 ms in WT, n=10–12, p<0.05). At the same time point, mRNA of the calcium-handling proteins PLB, NCX and SERCA, and of the fibrotic marker genes collagen I, fibronectin and elastin were dramatically reduced in atrial tissue of JDP2 compared to WT mice (n=6, p<0.05), and may be functionally involved in atrial conduction defects.

Conclusion

Enhanced expression of JDP2 provokes ventricular dysfunction and fibrosis within one week, whereas changes in the atrial tissue and conduction defects occur later and seem to be a secondary effect that is provoked by the pre-existing ventricular dysfunction.

P6485Incremental prognostic value of electrocardiographic strain after transcatheter aortic valve replacement for aortic stenosis

Background

Electrocardiographic (ECG) strain pattern has recently been associated with increased adverse outcome in aortic stenosis (AS) and after surgical aortic valve replacement (AVR). However, the relation linking ECG strain and cardiovascular MACE in patients with transcatheter aortic valve replacement (TAVR) has not been yet described.

Objectives

The aim of our study was to determine the impact and incremental value of ECG Strain pattern in predicting adverse outcome after TAVR.

Methods

585 patients with severe AS (mean age: 83±7 male 39.8%) were enrolled from November 2012 to May 2018. ECG strain pattern was defined as ≥1 mm concave down-sloping ST-segment depression and asymmetrical T-wave inversion in the lateral leads. Patients with baseline left bundle branch block (LBBB), right bundle branch block (RBBB) or ventricular paced rhythm were excluded. All patients underwent transthoracic echocardiography (TTE) before TAVR and at 30 days follow up. The primary endpoints of the study were the overall all-cause mortality after TAVR, rehospitalization for Hearth failure (HF), myocardial infarction and stroke.

Results

178 (30.4%) patients were excluded from analyses owing to the presence of either LBBB (n=103) or RBBB (n=75). Among the 407 remaining patients, 106 had ECG strain pattern (26.04%). Patients with ECG strain were significantly younger (81.6±8 years vs 83.5±6.8 years; p=0.022), had lower BMI (23±4.5 kg.m2 vs 27.9±6.8 kg.m2; p=0.02) more severe AS (mean gradient 52.3±15.2 mmHg vs 47.9±11.8 mmHg; p=0.003), significant lower LVEF (51.8±15% vs 58.4±10.7%; p<0.001). Left ventricular hypertrophy (LVH) was more frequent in patients with ECG Strain (indexed left ventricular mass (135.9±33.4 g.m2 vs 123.6±31.9 g.m2; p=0.002)). Death from any cause (22 (20.8%) vs 61 (20.3%); p=0.508) did not differ significantly between groups. Major adverse cardiovascular events (MACE) including death, stroke and heart failure at 1 month showed similar incidence (7 (6.6%) vs 17 (5.6%), p=0.439). Rehospitalization for hearth failure (HF) was significantly higher (33 (31.1%) vs 33 (11%); p<0.001) in patients with ECG strain pattern. In univariate model, ECG Strain was a strong predictor of rehospitalization for HF (HR 2.621 95% CI (1.607–4.277), p=0.001), independently of LVH assessed either by ECG criteria (HR 1.181 95% CI (0.698–1.997; p=0.536) or TTE (HR 1.557 95% (CI 0.701–3.458; p=0.277). ECG Strain remained associated with a higher risk of rehospitalization for hearth failure in multivariate analyses (HR 2.747 95% (CI 1.614- 4.674); p<0.001)

Conclusion

In patients with AS eligible for TAVR, ECG Strain Pattern is frequent and associated with an increased risk of post interventional heart failure regardless of preoperative LVH. ECG Strain pattern represents an easy, objective, reliable and low-cost tool to identify patients who may benefit from an extend and intensified post-interventional follow-up.

[S2 Alar-Iliac Screws in Fixation and Correction of Combined Neuromuscular Spinal and Pelvic Deformities]

PURPOSE OF THE STUDY Neuromuscular deformities of the spine represent surgically uneasy to solve problems as well as serious handicaps causing sitting instability, pressure ulcers as well as pain. The aim of our study is to conduct a retrospective clinical analysis of the results of surgical correction of these deformities. This paper presents the use of a recent technique of sacral-alar-iliac (S2AI) screws and its comparison with other techniques of pelvic stabilisation. MATERIAL AND METHODS The group of 41 patients treated surgically with S2AI screws technique and transpedicular or hybrid instrumentation of the spine consisted of patients with the primary diagnosis of muscular dysthrophy, spinal muscular atrophy, cerebral palsy and some other neuromuscular diseases. The results of pelvic obliquity correction and scoliotic correction in combined neuromuscular deformities of the spine and pelvis were analysed. The technique of S2AI screws implantation and the possibility of their free-hand technique implementation were presented. RESULTS In the followed-up group of patients an average correction of pelvic obliquity by 81% (from 29.1 degrees before the operation to 5.6 degrees after the operation) was reported. On average, 74% correction of scoliotic spine deformity was achieved (from 83.3 degrees before the operation to 22.5 degrees after the operation). In both the cases neither a significant loss of correction at the minimum one-year follow-up nor any serious complications associated with grappling of pelvic fixation were observed. DISCUSSION The S2AI screws offer at least the same stability and ability of correction as iliac screws and at the same time they provide significantly better results compared with the older methods of pelvic fixation such as the Galvestone technique. With a good knowledge of the surgical technique and anatomical aspects this technique can be applied in the form of a free-hand technique. Navigation as well as robotic techniques can help with the accurate positioning of the S2AI screw. Transfixation of sacroiliacal syndesmosis in patients with a neuromuscular handicap does not lead to deterioration of their mobility. CONCLUSIONS Simultaneous stabilisation of spine and pelvis makes it possible to achieve a good quality correction of the deformity and good clinical results over a long period of time. It allows for stability of the sitting position of the patients and improves the quality of their lives. Nowadays, the S2AI screws are considered to be biomechanically the best quality pelvic fixation, eliminating subcutaneous prominence of the instrumentation and reducing the risk of skin decubitus. Key words:neuromuscular deformity, sacral-alar-iliac screw, pelvic obliquity, stabilization, scoliosis.

The effect of the dietary protein restriction and re-feeding on the content of leptin, IGF-I and urea nitrogen in the blood plasma and growth performance in pigs

The aim of the present study was to examine the effect of the dietary protein restriction on the plasma concentrations of leptin, insulin-like growth factor (IGF-I), blood urea nitrogen (BUN) and growth performance in growing pigs. A total of 12 gilts were divided into experimental (ET) and control (CT) treatments. After the 14-day dietary restriction period during which the ET fed a low-protein diet (LPD, 5% of crude protein) and the CT fed a standard diet (SD, 16% of crude protein) the second 14-day re-feeding period followed, in which LPD was replaced by a SD that was fed by the both treatments. During the dietary protein restriction reduced (P < 0.05) N intake, average daily gain (ADG), concentration of BUN and tendency (P = 0.084) to the lower IGF-I in ET compared with CT were observed. Feed to gain ratio was greater (P < 0.05) in ET. During the subsequent re-feeding period, there was a tendency to the greater daily feed intake (P = 0.068) and N intake (P = 0.070), greater (P < 0.05) ADG, BUN and plasma leptin but no IGF-I in ET. These observations suggest that dietary protein restriction promotes body growth in pigs, which is associated with increase in blood leptin and BUN level in ET during the re-feeding, indicating that the increased ADG can be due to increased fat deposition but not of protein synthesis.

Chromic oxide and acid-insoluble ash as markers in digestibility studies with growing pigs and sows

The results of three experiments, focused on the determination of endogenous ileal flow (EIF) of amino acids (AA) and nitrogen (N) (Exp. 1), apparent ileal digestibility (AID) of AA and N (Exp. 2), and apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), N, calcium (Ca) and phosphorus (P) (Exps. 2 and 3), were used to compare chromic oxide (Cr₂ O₃ ) and acid-insoluble ash (AIA) as digestibility markers. In Exps. 1 and 2, a total of six gilts fitted with T-cannula in terminal ileum, and in Exp. 3, a total of 24 pregnant sows were used. In Exps. 1 and 2, the pigs were assigned into four dietary treatments according to 4 × 6 crossover design (Exp. 1; diets with 0%, 4%, 8% and 12% of casein; Exp. 2 basal diet with different levels of phytase). In Exp. 3, the sows were assigned to four dietary treatments (basal diet with different levels of phytase) of six sows. In Exps. 1 and 2 ileal digesta and in Exps. 2 and 3 faeces were collected for the determination of EIF, AID and ATTD. Differences in EIF of AA determined by Cr₂ O₃ and AIA ranged (p ˃ 0.05) from -4.62 to 4.54%. The lowest EIF was for methionine and the greatest one for proline, determined by both markers. Apparent ileal digestibility determined by Cr₂ O₃ was slightly greater (p ˃ 0.05) in comparison with AIA. Differences ranged from 1.88% (Arg) to 7.08% (Gly). The greatest AID was for arginine and the lowest one for glycine, determined by both Cr₂ O₃ and AIA. Similarly for ATTD of DM, OM, N, Ca and P, there were no differences in digestibility determined by Cr₂ O₃ and AIA. Both, Cr₂ O₃ and AIA, are suitable and comparable markers for digestibility studies in pigs.

Molecular switches under TGFβ signalling during progression from cardiac hypertrophy to heart failure

Cardiac hypertrophy is a mechanism to compensate for increased cardiac work load, that is, after myocardial infarction or upon pressure overload. However, in the long run cardiac hypertrophy is a prevailing risk factor for the development of heart failure. During pathological remodelling processes leading to heart failure, decompensated hypertrophy, death of cardiomyocytes by apoptosis or necroptosis and fibrosis as well as a progressive dysfunction of cardiomyocytes are apparent. Interestingly, the induction of hypertrophy, cell death or fibrosis is mediated by similar signalling pathways. Therefore, tiny changes in the signalling cascade are able to switch physiological cardiac remodelling to the development of heart failure. In the present review, we will describe examples of these molecular switches that change compensated hypertrophy to the development of heart failure and will focus on the importance of the signalling cascades of the TGFβ superfamily in this process. In this context, potential therapeutic targets for pharmacological interventions that could attenuate the progression of heart failure will be discussed.

Cafedrine/theodrenaline in anaesthesia: influencing factors in restoring arterial blood pressure

Background

Hypotensive states that require fast stabilisation of blood pressure can occur during anaesthesia. In 1963, the 20:1 mixture of cafedrine/theodrenaline (Akrinor^®) was introduced in Germany for use in anaesthesia and emergency medicine in the first-line management of hypotensive states. Though on the market for many years, few pharmacodynamic data are available on this combination net beta-mimetic agent.

Aim

This study aimed to examine the drug combination in real-life clinical practice and recorded time to 10 % mean arterial blood pressure (MAP) increase and heart rate. Furthermore, potential factors that influence drug effectiveness under anaesthesia were assessed.

Methods

Data were collected within a standardised anaesthesia protocol. A total of 353 consecutive patients (female/male = 149/204) who received cafedrine/theodrenaline after a drop in MAP ≥ 5 % were included in the study. The time to 10 % increase in MAP, dosage of cafedrine/theodrenaline, volume loading, blood pressure and heart rate were monitored over time.

Results

Patients were a mean (standard deviation) of 64.4 ± 15.1 years old with a baseline MAP of 82 ± 14 mmHg, which dropped to a mean of 63 ± 10 mmHg during anaesthesia without gender differences. Cafedrine/theodrenaline (1.27 ± 1.0 mg/kg; 64 ± 50 µg/kg) significantly increased MAP (p < 0.001) by 11 ± 16 mmHg within 5 min, reaching peak values within 17.4 ± 9.0 min. Heart rate was not affected in a clinically significant manner. Cafedrine/theodrenaline induced a 10 % MAP increase after 7.2 ± 4.6 min (women) and after 8.6 ± 6.3 min (men) (p = 0.018). Independent of gender, the dose of cafedrine/theodrenaline required to achieve the observed MAP increase of 14 ± 16 mmHg at 15 min was significantly different in patients with heart failure [1.78 ± 1.67 mg/kg (cafedrine)/89.0 ± 83.5 µg/kg (theodrenaline)] compared with healthy patients [1.16 ± 0.77 mg/kg (cafedrine)/58.0 ± 38.5 µg/kg (theodrenaline)] (p = 0.005). Concomitant medication with beta-blocking agents significantly prolonged the time to 10 % MAP increase [9.0 ± 7.0 vs. 7.3 ± 4.3 min (p = 0.008)].

Conclusion

Cafedrine/theodrenaline quickly restores MAP during anaesthesia. Female gender is associated with higher effectiveness, while heart failure and beta-blocker administration lower the anti-hypotonic effect. Prospective studies in defined patient populations are warranted to further characterise the effect of cafedrine/theodrenaline.

Effect of dietary fiber and crude protein content in feed on nitrogen retention in pigs

Eight gilts (29.9 ± 1.7 kg initial BW) were used to evaluate effects of dietary (crude) fiber on N excretion via feces and urine at 2 levels of dietary CP. Pigs were fed 4 dietary treatments according to a double 4 × 4 Latin square. Treatments were low (14%) CP and low (3.25%) (crude) fiber (LPAA), low CP and high (4.46%) fiber (LPAABP), high (18.8%) CP and low fiber (HP), and high CP and high fiber (HPBP). Diets were based on soybean (Glycine max) meal, wheat (Triticum aestivum), and maize (Zea mays) and were supplemented with crystalline AA. High fiber diets contained 15% dried beet (Beta vulgaris) pulp. Pigs were housed in metabolic cages and fed 2 equal meals at 0700 and 1700 h at a daily rate of 90 g/kg BW(0.75). Water was offered ad libitum. Each experimental period consisted of a 6-d adaptation followed by a 4-d collection of feces and urine (bladder catheters). Data were analyzed using ANOVA. Differences between means (P < 0.05) were assessed using Fisher's LSD procedure. The N intake, fecal N excretion and absorption, and N retention increased (P < 0.05) in pigs fed high-CP diets with added fiber (HP vs. HPBR). With added fiber, urinary N excretion (g/d) was reduced (P < 0.02) only for the low-CP diet. Urinary N as a percentage of N intake was reduced (P < 0.01) in both groups fed high-fiber diets irrespective of dietary CP content. Dietary fiber level did not affect DMI. Fecal DM excretion (g/d) was higher (P < 0.02) in pigs fed diets with high CP and high fiber content than in pigs fed diets with high CP and low fiber content. In conclusion, beet pulp fiber added to diets increased fecal N and reduced urinary N and in diets with higher CP content increased overall N retention.

Nutritional characteristics of by-products originating from the Central European ethanol fuel industry for pigs

Chemical composition and nutrient and energy digestibilities were determined in 4 samples of dried distillers grains with solubles (DDGS) and 1 sample of wet distillers grains (WDG) from 4 ethanol fuel manufacturers. The cereal sources used for ethanol production were wheat (Triticum aestivum; 1 sample), wheat + barley (Hordeum vulgare; 2 samples), and maize (Zea mays; 2 samples). The nutrient contents (expressed as % of DM) were variable, ranging from 30.5 to 39.5 CP, 4.4 to 12.3 fat, 7.5 to 12.9 crude fiber, 2.7 to 7.8 ash, and 0.4 to 0.9 total P. The concentration of Lys ranged from 2.05 to 5.20 g/kg DM. The diets were fed to 6 gilts (39.9 ± 1.9 kg BW) fitted with ileal T-cannulas using a 5 × 6 Youden square. Each experimental period comprised a 5-d adaptation followed by a 2-d collection of urine and feces and 1-d (24 h) collection of ileal digesta. Using acid-insoluble ash as a marker, apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients and energy and AID of AA were calculated. The ATTD of N ranged from 55.7 to 83.7%. The N retention expressed as percentage of N intake ranged from 10.2 to 32.0. Except for wheat-based DDGS, the AID of N was 66.8%. The ATTD and AID values of NDF were 52.8 and 24.4%, respectively. The concentration of total P in WDG was half of values in DDGS, which likely caused its very low ATTD (1.4%). The ATTD and AID of energy ranged from 58.8 to 73.9% and from 40.6 to 54.1%, respectively. The AID of AA was greatest (P < 0.001) in WDG (71.8%) and lowest (P < 0.001) in DDGS from wheat (44.8%). In conclusion, nutrient variability among DDGS samples varies greatly, and source of origin is an important determinant of quality.

Growth differentiation factor 15 acts anti-apoptotic and pro-hypertrophic in adult cardiomyocytes

Growth differentiation factor 15 (GDF15) is induced during heart failure development, and may influence different processes in cardiac remodeling. While its anti-apoptotic action under conditions of ischemia-reperfusion have been shown, it remained unclear if this is a broadly protective effect applicable to other apoptotic stimuli. Furthermore, effects on cardiac hypertrophy remained obscure. Therefore, we investigated the effects of GDF15 on induction of hypertrophy and apoptosis in ventricular cardiomyocytes. GDF15 (3 ng/ml) enhanced hypertrophic growth of cardiomyocytes as determined by an increase in cell size by 27 +/- 5% and rate of protein synthesis by 47 +/- 15%. In addition, a time and dose-dependent increase in SMAD-binding affinity was found, as well as enhanced phosphorylation of R-SMAD1. Inhibition of SMADs by transformation of cardiomyocytes with SMAD-decoy oligonucleotides abolished the hypertrophic growth effect. Specific inhibitors of PI3K (10 microM LY290042 or 10 nM wortmannin) or ERK (10 microM PD98059) also blocked GDF15-induced hypertrophy and SMAD activation. Apoptosis induction by three different agents, 100 nM angiotensin II, 1 ng/ml TGFbeta(1), or the NO-donor SNAP (100 microM) was blocked by addition of GDF15 (3 ng/ml). Scavenging of SMADs by transformation of cardiomyocytes with SMAD-decoy oligonucleotides abolished the anti-apoptotic effect of GDF15. In conclusion, GDF15 protects ventricular cardiomyocytes against different apoptotic stimuli and enhances hypertrophic growth. Hypertrophic signaling is thereby mediated via the kinases PI3K and ERK and the transcription factor R-SMAD1. Thus, GDF15 may influence cardiac remodeling via two different mechanisms, apoptosis protection and induction of hypertrophy.

Individual response of growing pigs to sulphur amino acid intake

Two N balance experiments were conducted to study the individual response of growing pigs to limiting amino acid (AA) intake. Series of fifteen diets with increasing concentration of sulphur amino acids (SAA, Expt 1) or methionine in the presence of excess cystine (Expt 2) were fed sequentially to nine pigs during a 15-day experimental period. The concentration of the AA under test ranged from 50% to 140% of the requirement while other essential AA were given in a 25% excess relative to the limiting AA. N retention was related to the limiting AA intake using rectilinear and curvilinear models. In Expt 1, the quadratic-plateau model fitted the individual data significantly better (p = 0.01) than the linear-plateau model. No difference was found between the two models in Expt. 2, presumably due to the sparing effect of excess cystine on methionine utilization. Exponential, saturation kinetics or four-parameter logistic models fitted to data for all pigs showed that their goodness of fit was similar to those of quadratic-plateau or linear-plateau models. Significant differences (p < 0.05) were found between individual plateau values for N retention within each experiment while the slopes of the regression lines did not significantly differ either in Expt 1 (p = 0.07) or Expt 2 (p = 0.45). There was a positive correlation between the slope and plateau values of the linear-plateau model in Expt 1 (r = 0.74, p = 0.02) but no significant correlation was found in Expt 2 (r = -0.48, p = 0.13). Marginal efficiencies of SAA and methionine utilization derived from the linear-plateau model were 0.43 and 0.65 respectively. Based on linear-plateau and quadratic-plateau models, daily requirements of SAA and methionine for a 50 kg pig were estimated to be 13.0 and 5.9 g and 14.3 and 6.1 g respectively.

Direct effects of the angiotensin-converting enzyme inhibitor ramiprilat on adult rat ventricular cardiomyocytes

AIM

Angiotensin-converting enzyme (ACE) inhibitors like ramiprilat bind to ACE expressed on the cell surface of endothelial cells and induce cell-specific signalling including the activation of activator protein (AP)-1. The present study addressed the question whether ramiprilat exerts a similar effect on adult ventricular cardiomyocytes, i.e. activates the AP-1 or modifies contractile performance. It was further aimed to decide whether such effects depend on bradykinin receptors or whether they are directly mediated via ACE.

METHODS

Adult rat ventricular cardiomyocytes were isolated and cultured. mRNA expression of ACE was investigated by RT-PCR, AP-1 activation by gel mobility shift assays, and cardiac contractile performance by electrical pacing of isolated cells and analysis of cell shortening via a line-camera.

RESULTS

Cardiomyocytes stably express ACE. Ramiprilat increased maximal contraction velocity and shortened the time-to-peak of contraction. In contrast to effects evoked by bradykinin, such effects caused by ramiprilat were not attenuated by HOE 140, a bradykinin-receptor antagonist. These effects were also not attenuated in the presence of l-nitro-arginine, used to mimic bradykinin-dependent signalling. In cardiomyocytes, bradykinin but not ramiprilat activated AP-1. Ramiprilat activates AP-1 in endothelial cells that are known to respond to ramiprilat in this way.

CONCLUSION

Ramiprilat exerts direct, bradykinin-receptor independent effects on cardiomyocytes that improve cellular function without a corresponding effect on AP-1 activation or induction of AP-1 dependent effects. This newly described effect of ramiprilat may contribute to the protective effects seen by application of ACE inhibitors.

Repression of anti-apoptotic genes via AP-1 as a mechanism of apoptosis induction in ventricular cardiomyocytes

Nitric oxide (NO) is increased under several pathophysiological, mainly inflammatory processes in the heart and has been characterized as an inducer of apoptosis in cardiomyocytes. The transcription factor activating protein-1 (AP-1) has been identified as a mediator of NO-induced apoptosis. Genes that are regulated by AP-1 under apoptotic conditions have not been identified yet. Therefore, we performed a microarray analysis with subsequent real-time polymerase chain reaction (PCR) to identify genes regulated by AP-1 in NO-induced ventricular cardiomyocytes of rats and tested the functional role of these genes in apoptosis. Cardiomyocytes were transformed with AP-1 decoy oligonucleotides for inhibition of AP-1 activity. These, as well as non-transformed control cells, were stimulated with the NO donor (+/-)-S-nitroso-N-acetylpenicillamine (SNAP, 100 microM) for 2 h. Some of the genes with differential gene expression on microarrays were further analysed by real-time PCR. Genes that are induced by SNAP were not identified. However, four genes, pyridoxal kinase, heat shock protein 10 (Hsp10), antigen identified by monoclonal antibodies 4F2 (4F2) and myosin light chain 2, were downregulated by SNAP in presence of AP-1. Pyridoxal kinase, Hsp10 and 4F2 have anti-apoptotic effects in unstimulated cells because downregulation of their expression by antisense oligos induced apoptosis in cardiomyocytes. An involvement of these genes in NO-induced apoptosis could only be proven for pyridoxal kinase. In conclusion, using microarray technology, we identified three anti-apoptotic genes (Hsp10, 4F2 and pyridoxal kinase) in ventricular cardiomyocytes, which may help the cells to resist some apoptotic stimuli. The downregulation of these genes results in cardiomyocyte apoptosis. Prevention of their downregulation may protect cardiomyocytes against apoptotic stimuli, and this may be of therapeutic benefit.

Angiotensin II stimulates apoptosis via TGF-beta1 signaling in ventricular cardiomyocytes of rat

Elevations in angiotensin II (AngII) and transforming growth factor (TGF-beta1) levels are often found under conditions leading to progression of heart failure. From several studies, it is evident that AngII enhances TGF-beta1 expression via activator protein 1 (AP-1) activation, and that this pathway is involved in hypertrophic growth of the heart muscle and in the development of cardiac fibrosis. We now continued characterization of the signaling pathway stimulated by AngII in ventricular cardiomyocytes of rat and analyzed if the enhancement of TGF-beta1 expression by AngII may also contribute to apoptosis induction, which is another predictor of heart failure progression. Stimulation of cardiomyocytes with 100 nM AngII for 2 h activated the transcription factors AP-1 and GATA by 68.6+/-23.9 or 70.7+/-9.8%. Induction of both factors was mediated by p38 mitogen-activated protein kinase (MAPK) because it was totally blocked using a specific inhibitor of the kinase (SB202190). When GATA was inhibited by transformation of cardiomyocytes with decoy oligonucleotides, AngII could not enhance TGF-beta1 expression. This inhibition was observed on the mRNA level in real-time polymerase chain reaction and on the protein level in Western blots. As a consequence, upon AngII stimulation for 24 h, release of TGF-beta1 from cardiomyocytes was also reduced from 240.5+/-50.4 to 130.5+/-22.1% (p<0.05). In contrast to the early induction of GATA and AP-1, the transcription factor similar to mothers against decapentaplegic homolog (SMAD) was induced by AngII after 24 h. This stimulation was dependent on TGF-beta1 because it was blocked by antibodies specific for TGF-beta1. Twenty-four hours after AngII addition, the number of apoptotic cardiomyocytes increased by 6.5+/-1.2%, and this apoptosis induction was blocked when SMAD activity was inhibited by transformation of cardiomyocytes with SMAD decoy oligonucleotides. In conclusion, the transcription factors AP-1 and GATA are activated by p38 MAPK upon AngII stimulation, and both are needed to enhance TGF-beta1 expression in ventricular cardiomyocytes. TGF-beta1 acts in an autocrine loop on the cells to induce apoptosis via SMAD signaling. Thus, the often-found correlation between AngII, TGF-beta1, AP-1, and SMAD in pathogenesis of heart disease reflects the proapoptotic signaling pathway induced by AngII in cardiomyocytes.

[Slovak nomenclature of organic chemistry]

The paper describes the beginnings of Slovak nomenclature of organic compounds and the application of CNOC IUPAC rules in the Slovak language, comparing the different conditions of the origin of national nomenclature in the Czech and Slovak parts of former Czechoslovakia.

Efficiency of amino acid utilization in the growing pig at suboptimal levels of intake: branched-chain amino acids, histidine and phenylalanine + tyrosine

Five balance experiments on growing pigs were carried out to study the marginal efficiency of utilization of isoleucine, leucine, valine, histidine and phenylalanine + tyrosine and to estimate their requirements for maintenance. Purified diets based on casein and crystalline amino acids as the sole source of N contained graded levels of each amino acid, corresponding to protein accretion rates of 0, 33, 66, 99 and 132 g/day, respectively. All other essential amino acids were given in a 30% excess. N retention increased linearly (p < 0.01) as the dietary concentration of the limiting amino acid increased. Based on linear regression equations relating amino acid deposition in body protein to amino acid intake, marginal efficiencies of ileal digestible amino acid utilization were calculated to be isoleucine - 0.81, leucine - 0.81, valine - 0.82, histidine - 1.17 and phenylalanine + tyrosine - 0.67. Extrapolating the regression equations to zero N retention, the daily requirements of amino acids for N equilibrium were estimated to be (mg/kg0.75) isoleucine - 18, leucine - 33, valine - 23, histidine - 14 and phenylalanine + tyrosine - 43.