Inez Rodrigus

Sevoflurane but not propofol preserves myocardial function in coronary surgery patients

Background Sevoflurane has been shown to protect against myocardial ischemia and reperfusion injury in animals. The present study investigated whether these effects were clinically relevant and would protect left ventricular (LV) function during coronary surgery. Methods Twenty coronary surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with sevoflurane. Except for this, anesthetic and surgical management was the same in all patients. A high-fidelity pressure catheter was positioned in the left ventricle and the left atrium. LV response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dtmax. Effects on relaxation were assessed by analysis of the load dependence of myocardial relaxation (R = slope of the relation between time constant &tgr; of isovolumic relaxation and end-systolic pressure). Postoperative concentrations of cardiac troponin I were followed during 36 h. Results Before CPB, leg elevation slightly increased dP/dtmax in the sevoflurane group (5 ± 3%), whereas it remained unchanged in the propofol group (1 ± 6%). After CPB, leg elevation resulted in a decrease in dP/dtmax in the propofol group (−5 ± 4%), whereas the response in the sevoflurane group was comparable to the response before CPB (5 ± 4%). Load dependence of LV pressure fall (R) was similar in both groups before CPB. After CPB, R was increased in the propofol group but not in the sevoflurane group. Troponin I concentrations were significantly lower in the sevoflurane than in the propofol group. Conclusions Sevoflurane preserved LV function after CPB with less evidence of myocardial damage in the first 36 h postoperatively. These data suggest a cardioprotective effect of sevoflurane during coronary artery surgery.

Effects of Propofol, Desflurane, and Sevoflurane on Recovery of Myocardial Function after Coronary Surgery in Elderly High-risk Patients

Background The present study investigated the effects of propofol, desflurane, and sevoflurane on recovery of myocardial function in high-risk coronary surgery patients. High-risk patients were defined as those older than 70 yr with three-vessel disease and an ejection fraction less than 50% with impaired length-dependent regulation of myocardial function. Methods Coronary surgery patients (n = 45) were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with desflurane or sevoflurane. Cardiac function was assessed perioperatively and during 24 h postoperatively using a Swan-Ganz catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left and right atrium and ventricle. Response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dtmax. Effects on relaxation were assessed by analysis of the load-dependence of myocardial relaxation. Postoperative levels of cardiac troponin I were followed for 36 h. Results After CPB, cardiac index and dP/dtmax were significantly lower in patients under propofol anesthesia. Post-CPB, leg elevation resulted in a significantly greater decrease in dP/dtmax in the propofol group, whereas the responses in the desflurane and sevoflurane groups were comparable with the responses before CPB. After CPB, load dependence of left ventricular pressure drop was significantly higher in the propofol group than in the desflurane and sevoflurane group. Troponin I levels were significantly higher in the propofol group. Conclusions Sevoflurane and desflurane but not propofol preserved left ventricular function after CPB in high-risk coronary surgery patients with less evidence of myocardial damage postoperatively.

Procedural, 30-day and one year outcome following CoreValve or Edwards transcatheter aortic valve implantation: results of the Belgian national registry

We report clinical outcomes following transcatheter aortic valve implantation (TAVI), using the CoreValve revalving system (18 Fr transfemoral or subclavian) or the Edwards Sapien valve (22 Fr transfemoral or 24 Fr transapical) as part of a Belgian prospective non-randomized multicentre registry. All 15 Belgian centres performing TAVI participated to this registry (seven exclusively Edwards Sapien, eight exclusively CoreValve). All consecutive high-risk symptomatic patients with severe aortic stenosis were evaluated by a heart team and screened for eligibility for TAVI. Three hundred and twenty-eight patients underwent TAVI with CoreValve (n = 141; eight subclavian and 133 transfemoral) or Edwards Sapien (n = 187; 99 transfemoral and 88 transapical) up to April 2010. Procedural success was 97%. One-month survival was 88% for the Edwards and 89% for the CoreValve treated patients. One-month mortality was both related to cardiac and non-cardiac reasons. Overall one-year survival was 78% in the CoreValve transfemoral treated patients, 100% in the CoreValve subclavian treated patients, 82% in the Edwards transfemoral treated patients and 63% in the Edwards transapical treated patients. This mid-term mortality was mainly related to age-related, non-cardiac complications.

Hydroxyethyl starch 130/0.4 versus modified fluid gelatin for volume expansion in cardiac surgery patients: The effects on perioperative bleeding and transfusion needs

In this prospective, randomized, open controlled study we compared the effects on net red blood cell loss of 6% hydroxyethyl starch 130/0.4 (HES: n = 64) and 3% modified fluid gelatin (GEL: n = 68) administered for intravascular volume management in patients undergoing coronary surgery. Blood losses were calculated from determination of circulating blood volume and measurement of preoperative and postoperative hematocrit. Amount of colloids that could be administered was limited to 50 mL/kg. If additional fluids were required, balanced crystalloid solution was used. Anesthetic and surgical techniques were standardized. Both groups were similar with regard to demographic and intraoperative variables. Total study drug was 48.9 ± 17.2 mL/kg in the HES group and 48.9 ± 14.6 mL/kg in the GEL group. Total red blood cell loss was 544 ± 305 mL in the HES group and 504 ± 327 mL the GEL group. Measured blood losses were also similar in both groups (HES, 19.4 ± 12.3 mL/kg; GEL, 19.2 ± 14.5 mL/kg). Exposure to allogeneic blood product was comparable in both groups. In the conditions of the present study, HES 130/0.4 up to 50 mL/kg is a valuable alternative to modified fluid gelatin for plasma volume expansion during and after cardiac surgery.

Mutations in a TGF-β Ligand, TGFB3, Cause Syndromic Aortic Aneurysms and Dissections

Background Aneurysms affecting the aorta are a common condition associated with high mortality as a result of aortic dissection or rupture. Investigations of the pathogenic mechanisms involved in syndromic types of thoracic aortic aneurysms, such as Marfan and Loeys-Dietz syndromes, have revealed an important contribution of disturbed transforming growth factor (TGF)-β signaling. Objectives This study sought to discover a novel gene causing syndromic aortic aneurysms in order to unravel the underlying pathogenesis. Methods We combined genome-wide linkage analysis, exome sequencing, and candidate gene Sanger sequencing in a total of 470 index cases with thoracic aortic aneurysms. Extensive cardiological examination, including physical examination, electrocardiography, and transthoracic echocardiography was performed. In adults, imaging of the entire aorta using computed tomography or magnetic resonance imaging was done. Results Here, we report on 43 patients from 11 families with syndromic presentations of aortic aneurysms caused by TGFB3 mutations. We demonstrate that TGFB3 mutations are associated with significant cardiovascular involvement, including thoracic/abdominal aortic aneurysm and dissection, and mitral valve disease. Other systemic features overlap clinically with Loeys-Dietz, Shprintzen-Goldberg, and Marfan syndromes, including cleft palate, bifid uvula, skeletal overgrowth, cervical spine instability and clubfoot deformity. In line with previous observations in aortic wall tissues of patients with mutations in effectors of TGF-β signaling (TGFBR1/2, SMAD3, and TGFB2), we confirm a paradoxical up-regulation of both canonical and noncanonical TGF-β signaling in association with up-regulation of the expression of TGF-β ligands. Conclusions Our findings emphasize the broad clinical variability associated with TGFB3 mutations and highlight the importance of early recognition of the disease because of high cardiovascular risk.

Cardioprotective properties of sevoflurane in patients undergoing aortic valve replacement with cardiopulmonary bypass.

In coronary surgery patients the use of a volatile anesthetic regimen with sevoflurane was associated with a better recovery of myocardial function and less postoperative release of troponin I. In the present study we investigated whether these cardioprotective properties were also apparent in the cardiac surgical setting of aortic valve replacement (AVR) surgery for the correction of aortic stenosis. Thirty AVR surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhaled anesthesia with sevoflurane. Cardiac function was assessed perioperatively using a pulmonary artery catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left ventricle. Postoperative concentrations of cardiac troponin I were followed for 48 h. After cardiopulmonary bypass (CPB), stroke volume and dP/dtmax were significantly higher in the patients with sevoflurane. Post-CPB, the effects of an increase in cardiac load on dP/dtmax were similar to pre-CPB in the sevoflurane group (1.0 % ± 5.4% post-CPB versus 1.3% ± 8.6% pre-CPB) but more depressed in the propofol group (−8.2% ± 4.4% post-CPB versus 0.1% ± 4.9% pre-CPB). The rate of relaxation was significantly slower post-CPB in the propofol group. Postoperative levels of troponin I were significantly lower in the sevoflurane group. Our data indicate that the use of a volatile anesthetic regimen in AVR surgery was associated with better preservation of myocardial function and a reduced postoperative release of troponin I.

Contraction-relaxation coupling and impaired left ventricular performance in coronary surgery patients

BACKGROUND Dependence of left ventricular (LV) relaxation on cardiac systolic load is a function of myocardial contractility. The authors hypothesized that, if a tight coupling would exist between LV contraction and relaxation, the changes in relaxation rate with an increase in cardiac systolic load would be related to the changes in LV contraction. METHODS Coronary surgery patients (n = 120) with preoperative ejection fraction >40% were included. High-fidelity LV pressure tracings (n = 120) and transgastric transesophageal echocardiographic data (n = 40) were obtained. Hearts were paced at a fixed rate of 90 beats/min. Effects on contraction were evaluated by analysis of changes in dP/dt(max) and stroke area. Effects on relaxation were assessed by analysis of R (slope of the relation between tau and end-systolic pressure). Correlations were calculated with linear regression analysis using Pearsons coefficient r. RESULTS Baseline LV end-diastolic pressure was 10+/-3 mm Hg (mean +/- SD). During leg raising, systolic LV pressure increased from 93+/-9 to 107+/-11 mm Hg. The change in dP/dt(max) was variable and ranged from -181 to +254 mm Hg/s. A similar variability was observed with the changes in stroke area, which ranged from -2.0 to +5.5 cm2. Changes in dP/dt(max) and in stroke area were closely related to individual R values (r = 0.87, P<0.001; and r = 0.81, P<0.001, respectively) and to corresponding changes in LV end-diastolic pressure (r = 0.81, P< 0.001; and r = 0.74, P<0.001, respectively). CONCLUSIONS A tight coupling was observed between contraction and relaxation. Leg raising identified patients who developed a load-dependent impairment of LV performance and increased load dependence of LV relaxation.

Comparison of Magnetic Resonance Imaging of Aortic Valve Stenosis and Aortic Root to Multimodality Imaging for Selection of Transcatheter Aortic Valve Implantation Candidates

The purpose of the present study was to compare the aortic valve area, aortic valve annulus, and aortic root dimensions measured using magnetic resonance imaging (MRI) with catheterization, transthoracic echocardiography (TTE), and transesophageal echocardiography (TEE). An optimal prosthesis--aortic root match is an essential goal when evaluating patients for transcatheter aortic valve implantation. Comparisons between MRI and the other imaging techniques are rare and need validation. In 24 consecutive, high-risk, symptomatic patients with severe aortic stenosis, aortic valve area was prospectively determined using MRI and direct planimetry using three-dimensional TTE and calculated by catheterization using the Gorlin equation and by Doppler echocardiography using the continuity equation. Aortic valve annulus and the aortic root dimensions were prospectively measured using MRI, 2-dimensional TTE, and invasive aortography. In addition, aortic valve annulus was measured using TEE. No differences in aortic valve area were found among MRI, Doppler echocardiography, and 3-dimensional TTE compared with catheterization (p = NS). Invasive angiography underestimated aortic valve annulus compared with MRI (p <0.001), TEE (p <0.001), and 2-dimensional TTE (p <0.001). Two-dimensional TTE tended to underestimate the aortic valve annulus diameters compared to TEE and MRI. In contrast to 2-dimensional TTE, 3 patients had aortic valve annulus beyond the transcatheter aortic valve implantation range using TEE and MRI. In conclusion, MRI planimetry, Doppler, and 3-dimensional TTE provided an accurate estimate of the aortic valve area compared to catheterization. MRI and TEE provided similar and essential assessment of the aortic valve annulus dimensions, especially at the limits of the transcatheter aortic valve implantation range.

Is EuroSCORE useful in the prediction of extended intensive care unit stay after cardiac surgery

OBJECTIVE Risk stratification allows preoperative assessment of cardiac surgical risk faced by individual patients and permits retrospective analysis of postoperative complications in the intensive care unit (ICU). The aim of this single-center study was to investigate the prediction of extended ICU stay after cardiac surgery using both the additive and logistic model of the European System for Cardiac Operative Risk Evaluation (EuroSCORE). METHODS A retrospective observational study was conducted. We collected clinical data of 1562 consecutive patients undergoing cardiac surgery over a 2-year period at the Antwerp University Hospital, Belgium. EuroSCORE values of all patients were obtained. The outcome measure was the duration of ICU stay in days. The predictive performance of EuroSCORE was analyzed by the discriminatory power of a receiver operating characteristic (ROC) curve. Each EuroSCORE value was used as a theoretical cut-off point to predict duration of ICU stay. Three subsequent ICU stays were defined as prolonged: more than 2, 5 and 7 days. ROC curves were constructed for both the additive and logistic model. RESULTS Patients had a median ICU stay of 2 days and a mean ICU stay of 5.5 days. Median additive EuroSCORE was 5 (range, 0-22) and logistic EuroSCORE was 3.94% (range, 0.00-87.00). In the additive EuroSCORE model, a predictive value of 0.76 for an ICU stay of >7 days, 0.72 for >5 days and 0.67 for >2 days was found. The logistic EuroSCORE model yielded an area under the ROC curve of 0.77, 0.75 and 0.68 for each ICU length of stay, respectively. CONCLUSIONS In our patient database, prolonged length of stay in the ICU correlated positively with EuroSCORE. The logistic model was more discriminatory than the additive in tracing extended ICU stay. The overall predictive performance of EuroSCORE is acceptable and most likely based on the presence of variables that are risk factors for both mortality and extended ICU stay. Hence, EuroSCORE is a useful predicting tool and provides both surgeons and intensivists with a good estimate of patient risk in terms of ICU stay.

Extracellular nucleoside diphosphate kinase NM23/NDPK modulates normal hematopoietic differentiation

OBJECTIVE We previously demonstrated the presence of nucleoside diphosphate kinase NDPK/NM23 in normal human plasma. It also was reported that extracellular NM23 could inhibit differentiation of certain hematopoietic cell lines. We further investigated the extracellular effect of NM23 on hematopoiesis by adding recombinant NM23-H1, NM23-H2, and NM23-H3 proteins to in vitro differentiation assays of normal human hematopoietic progenitors. MATERIALS AND METHODS To study the effect on the earlier stages of hematopoietic maturation, NM23 was added to serum-free pre-colony-forming unit (pre-CFU) assays starting from immature CD34++CD38- bone marrow cells. Serum-free CFU assays starting from CD34+ CD38+ bone marrow cells were used as a model for terminal hematopoietic differentiation. RESULTS In pre-CFU assays, none of the NM23 isoforms used significantly changed the expansion of CD34++CD38- cells, nor did NM23 alter the CD34++ CD38- cell lineage commitment. In contrast, terminal differentiation of CD34+CD38+ progenitor cells in CFU assays was significantly altered by addition of NM23 protein. More erythroid burst-forming units and fewer macrophage colonies were observed in cultures containing any of the NM23 isoforms examined. Similar effects were observed using the enzymatically inactive H118N mutant of NM23-H1, strongly suggesting that the observed effect is independent of the nucleoside diphosphate kinase activity of NM23. CONCLUSION We demonstrated a modulating effect of extracellular NM23 proteins on the terminal stages of normal hematopoietic differentiation. Therefore, the fairly high concentrations of NM23 constitutively present in plasma could have a physiologic role in supporting erythropoiesis and inhibiting excessive macrophage formation.