Mathias Kubik

Radial Artery Applanation Tonometry for Continuous Noninvasive Cardiac Output Measurement: A Comparison With Intermittent Pulmonary Artery Thermodilution in Patients After Cardiothoracic Surgery.

Objectives:Radial artery applanation tonometry allows completely noninvasive continuous cardiac output estimation. The aim of the present study was to compare cardiac output measurements obtained with applanation tonometry (AT-CO) using the T-Line system (Tensys Medical, San Diego, CA) with cardiac output measured by intermittent pulmonary artery thermodilution using a pulmonary artery catheter (PAC-CO) with regard to accuracy, precision of agreement, and trending ability. Design:A prospective method comparison study. Setting:The study was conducted in a cardiosurgical ICU of a German university hospital. Patients:We performed cardiac output measurements in 50 patients after cardiothoracic surgery. Interventions:None. Measurements and Main Results:Three independent sets of three consecutive thermodilution measurements (i.e., PAC-CO) each were performed per patient, and AT-CO was measured simultaneously. The average of the three thermodilution cardiac output measurements was compared with the average of the corresponding three AT-CO values resulting in 150 paired cardiac output measurements. In 13 patients, cardiac output–modifying maneuvers performed for clinical reasons additionally allowed to evaluate trending ability. For statistical analysis, we used Bland-Altman analysis, the percentage error, four-quadrant plot, and concordance analysis. Mean PAC-CO was 4.7u2009±u20091.2u2009L/min and mean AT-CO was 4.9u2009±u20091.1u2009L/min. The mean of differences was –0.2u2009L/min with 95% limits of agreement of –1.8 to + 1.4u2009L/min. The percentage error was 34%. The concordance rate was 95%. Conclusions:Continuous cardiac output measurement using the noninvasive applanation tonometry technology is basically feasible in ICU patients after cardiothoracic surgery. The applanation tonometry technology provides cardiac output values with reasonable accuracy and precision of agreement compared with intermittent pulmonary artery thermodilution measurements in a clinical study setting and is able to reliably track cardiac output changes induced by cardiac output–modifying maneuvers.

Isolated Permanent Right Ventricular Assistance Using the HVAD Continuous-Flow Pump

Acute isolated right ventricular (RV) failure from myocardial infarction is a rare scenario. To date, there are no assist devices developed or approved for permanent isolated right heart support. We report on the successful implantation of a HeartWare HVAD as an isolated RV assist in a patient who suffered extended RV myocardial infarction after iatrogenic dissection of the right coronary artery. No manipulations of the system were required to adapt the assist device to the pulmonary circulation.

Percutaneous mitral valve repair as a bail-out strategy for patients with severe mitral regurgitation after cardiac surgery

From the Departments of General and Interventional Cardiology, and Cardiovascular Surgery, University Heart Center Hamburg, Germany. Disclosures: Dr Franzen received funding for proctoring from E-Valve Inc, Menlo Park, California, and Abbott Laboratories, Abbott Park, Illinois. Drs Franzen and Seiffert contributed equally to this work. Received for publication May 18, 2010; accepted for publication Oct 23, 2010; available ahead of print Jan 19, 2011. Address for reprints: Moritz Seiffert, MD, Department of Cardiovascular Surgery, University Heart Center Hamburg, Martinistrasse 52, 20246 Hamburg, Germany (E-mail: m.seiffert@uke.de). J Thorac Cardiovasc Surg 2011;142:227-30 0022-5223/

Efficacy of prophylactic intra-aortic balloon pump therapy in chronic heart failure patients undergoing cardiac surgery.

36.00 Copyright 2011 by The American Association for Thoracic Surgery doi:10.1016/j.jtcvs.2010.10.037

Outcomes of Minimally Invasive Temporary Right Ventricular Assist Device Support for Acute Right Ventricular Failure During Minimally Invasive Left Ventricular Assist Device Implantation

This study investigated the efficacy of prophylactic intraoperative intra-aortic balloon pump (IABP) usage in chronic heart failure patients with severely reduced left ventricular function undergoing elective cardiac surgery. Between January 2008 and December 2012, 107 patients with severely reduced left ventricular ejection fraction (LVEF <35%) received prophylactic intraoperative IABP implantation during open-heart surgery. Surgical procedures performed were isolated coronary artery bypass grafting (CABG) in 35 patients (32.7%), aortic valve replacement in 12 (11.2%), mitral valve repair or replacement in 15 (14.0%), combined valve and CABG procedures in 27 (25.2%), and other surgical procedures in 18 (16.8%). Results and outcomes were compared with those in a propensity score-matched cohort of 107 patients who underwent cardiac surgery without intraoperative IABP implantation. Matching criteria were age, gender, LVEF, and surgical procedure. Duration of intensive care unit (ICU) stay, duration of hospital stay, and 30-day mortality were markers of outcome. In the IABP group, mean patient age was 69.1 ± 13.7 years; 66.4% (70) were male. All IABPs were placed intraoperatively. Mean duration of IABP application time was 42.4 ± 8.7 h. IABP-related complications occurred in five patients (4.7%), including one case of inguinal bleeding, one case of mesenteric ischemia, and ischemia of the lower limb in three patients. No stroke or major bleeding occurred during IABP support. Mean durations of ICU and hospital stay were 3.38 ± 2.15 days and 7.69 ± 2.02 days, respectively, in the IABP group, and 4.20 ± 3.14 days and 8.57 ± 3.26 days in the control group, showing statistically significant reductions in duration of ICU and hospital stay in the IABP group (ICU stay, P = 0.036; hospital stay, P = 0.015). Thirty-day survival rates were 92.5 and 94.4% in the IABP and control group, respectively, showing no statistically significant difference (P = 0.75). IABP usage in chronic heart failure patients with severely reduced LVEF undergoing cardiac surgery was safe and resulted in shorter ICU and hospital stay but did not influence 7- and 30-day survival rates.

A comparison of volume clamp method-based continuous noninvasive cardiac output (CNCO) measurement versus intermittent pulmonary artery thermodilution in postoperative cardiothoracic surgery patients

Right ventricular failure (RVF) may still occur despite the benefits of minimally invasive left ventricular assist device (MI-LVAD) implantation. Our center strategy aims to avoid aggressive postoperative inotrope use by using mechanical support to facilitate right ventricle recovery and adaptation. We herein report first outcomes of patients with minimally invasive temporary right ventricular assist device (MI-t-RVAD) support for RVF during MI-LVAD implantation. Right ventricular failure was defined as requiring more than moderate inotopic support after weaning from cardiopulmonary bypass according to Interagency Registry for Mechanically Assisted Circulatory Support adverse event definitions. All patients requiring MI-t-RVAD support for RVF during MI-LVAD implantation between January, 2012 and April, 2016 were retrospectively reviewed. Clinical endpoints were death or unsuccessful RVAD weaning. Overall 10 patients (90% male, mean age 49.6u2009±u200914.8 years) underwent MI-t-RVAD implantation. Duration of MI-t-RVAD support was 16.2u2009±u200911.6 days. Right ventricular assist device weaning and subsequent uneventful awake device explantation was successful in all cases. The 30 day survival was 80%. Our results confirm safety and feasibility of MI-t-RVAD support for acute RVF in the setting of MI-LVAD implantation. The potential benefits of this strategy are more stable hemodynamics in the first postoperative days that usually are crucial for LVAD patients and reduced inotrope requirement.

Preoperative Ticagrelor administration leads to a higher risk of bleeding during and after coronary bypass surgery in a case-matched analysis

The CNAP technology (CNSystems Medizintechnik AG, Graz, Austria) allows continuous noninvasive arterial pressure waveform recording based on the volume clamp method and estimation of cardiac output (CO) by pulse contour analysis. We compared CNAP-derived CO measurements (CNCO) with intermittent invasive CO measurements (pulmonary artery catheter; PAC-CO) in postoperative cardiothoracic surgery patients. In 51 intensive care unit patients after cardiothoracic surgery, we measured PAC-CO (criterion standard) and CNCO at three different time points. We conducted two separate comparative analyses: (1) CNCO auto-calibrated to biometric patient data (CNCObio) versus PAC-CO and (2) CNCO calibrated to the first simultaneously measured PAC-CO value (CNCOcal) versus PAC-CO. The agreement between the two methods was statistically assessed by Bland–Altman analysis and the percentage error. In a subgroup of patients, a passive leg raising maneuver was performed for clinical indications and we present the changes in PAC-CO and CNCO in four-quadrant plots (exclusion zone 0.5xa0L/min) in order to evaluate the trending ability of CNCO. The mean difference between CNCObio and PAC-CO was +0.5xa0L/min (standard deviationu2009±u20091.3xa0L/min; 95% limits of agreement −1.9 to +3.0xa0L/min). The percentage error was 49%. The concordance rate was 100%. For CNCOcal, the mean difference was −0.3xa0L/min (±0.5xa0L/min; −1.2 to +0.7xa0L/min) with a percentage error of 19%. In this clinical study in cardiothoracic surgery patients, CNCOcal showed good agreement when compared with PAC-CO. For CNCObio, we observed a higher percentage error and good trending ability (concordance rate 100%).

Base excess is superior to lactate-levels in prediction of ICU mortality after cardiac surgery

OBJECTIVESnTo evaluate the effect of Ticagrelor on intra- and postoperative bleeding complications in patients undergoing coronary bypass surgery.nnnMETHODSnFor this study, patients who underwent on-pump or off-pump coronary bypass surgery with preoperative acetylsalicylic acid (ASA) and Ticagrelor administration, between January 2014 and December 2014, were included. In the matched control group, continued dual antiplatelet therapy (DAPT) consisted of Clopidogrel and ASA. A total of 28 consecutive patients (24 males; 73 ± 6.6 years) with preoperative Ticagrelor intake underwent elective (n = 22), urgent (n = 2) or emergency (n = 4) cardiac bypass surgery. The postoperative blood loss, red blood cell units given and intra- and postoperative bleeding complications were documented. To evaluate the effect of Ticagrelor treatment on bleeding during and after coronary bypass surgery in a non-randomized study, we used a case-matched analysis.nnnRESULTSnBaseline parameters showed no important differences between the study group and the control group regarding the matching variables, left ventricular function, preoperative clinical status and risk stratification. The preoperative laboratory analysis showed no important differences regarding coagulation and blood cell count parameters. Overall blood loss was significantly higher in the study group with a mean loss of 1028.8 ± 735.5 ml (P = 0.0002). Accordingly, units of red blood cells administered were also significantly higher in the study group (P = 0.0002). In the Ticagrelor group, there were six rethoracotomies due to postoperative bleeding with a blood loss of more than 1200 ml in the first 3 h. With no rethoracotomies in the Clopidogrel group, this also showed statistical significance for the postoperative course (P = 0.02). There were no differences found regarding ICU stay and ventilation time. Comparing the mean hospital stay, the study group presented a significantly longer stay than the control group (P = 0.001).nnnCONCLUSIONSnRecent studies about bleeding complications in patients with Ticagrelor intake undergoing CABG in a real-life scenario presented inconsistent data. We were able to show in a case-matched analysis that Ticagrelor administration leads to significantly higher blood loss, more red blood cell units transfused and a higher rate of rethoracotomies. The data also present a longer hospital stay to the disadvantage of the study group. Consequently, Ticagrelor intake before CABG procedures should be avoided or at least discontinued 3 days before cardiac surgery.

Percutaneous dilatation tracheostomy in patients with left ventricular assist device and established phenprocoumon therapy.

Introduction Cardiac surgery with the use of cardiopulmonary bypass is known to induce distinct metabolic changes. Respective changes in acid-base status including increased systemic lactate levels were previously related to clinical outcomes, but data remain controversial. Therefore, we aim to investigate the relevance of lactate and base excess (BE) levels on ICU-mortality in patients admitted to the ICU after cardiac surgery. Materials and methods Perioperative data of patients treated in a tertiary care academic center admitted to the ICU after on-pump surgery were analyzed in a retrospective fashion. Receiver operation characteristic (ROC) curves were constructed for admission lactate-levels and BE with calculation of optimal cut-off values to predict ICU mortality. Univariate followed by multivariate regression models were constructed to identify potential outcome-relevant indices. Results Data from 1,058 patients were included in the analysis. Area under the curves for prediction of ICU mortality were 0.79 for lactate levels at ICU admission (sensitivity 61.9%/ specificity 87.5%; optimal cut-off level 3.9mmol/l), and 0.7 for BE (sensitivity 52.4%/ specificity 93.8%, optimal cut-off level -6.7), respectively. Multivariate regression identified BE < -6.7 as the single metabolic predictor of ICU-mortality (HR 4.78, 95%-CI 1.4–16.33, p = 0.01). Explorative subgroup analyses revealed that the combination of lactate ≤3.9mmol/l and BE ≤ -6.7 has stronger impact on mortality than a combination of lactate of >3.9mmol/l and BE > -6.7 (HR 2.56, 95%-CI 0.18–37.17). Conclusions At ICU-admission, severely reduced BE appears superior to hyperlactatemia with regard to prediction of ICU-mortality in patients after cardiac surgery.

First successful use of the new ab5000 portable circulatory support console as bridge to recovery in a case of dilated cardiomyopathy

Over the last decade, the number of heart transplantations declined, and the number of implanted left ventricular assist devices (LVADs) markedly increased. Accordingly, common intensive care interventions rise and present their own challenges, especially because of the necessary anticoagulation regimen. One of these procedures is percutaneous dilatation tracheostomy (PDT). We herein report our experience with 34 patients with LVAD and established phenprocoumon therapy (International normalized ratio 2.1 ± 0.9, partial thromboplastin time 68.9 ± 19.0 seconds) who underwent PDT between 2006 and 2015 at our specialized cardiac surgery intensive care unit. Intraprocedural success was achieved in all cases (34/34 patients) with sufficient placement of the tracheal tube and adequate mechanical ventilation. No retained secretions or tracheostomy tube obstructions were observed during follow-up. In no case, conversion to surgical tracheostomy was necessary. No serious bleeding complications that required urgent or emergent reoperation occurred during or after the PDT procedure. A total of 16 patients (47.1%) died within the first 30 days after LVAD implantation. This is the first report describing outcomes of patients with LVAD under established phenprocoumon therapy and postoperative implemented PDT. PDT is a safe procedure for those patients. It is not connected with bleeding complications and shows a good procedural outcome.