Lachmandath Tewarie

EuroScore 2 for identification of patients for transapical aortic valve replacement - a single center retrospective in 206 patients

BackgroundOperative risk scoring algorithms identify patients with severe AS for transcatheter valve implantation in whom the anticipated operative mortality for conventional surgery would be considered prohibitive. We compared the three risk scores EuroScore 1 (LES), society of thoracic surgeons’ (STS) score and ACEF (age-creatinine-ejection fraction score) to the readjusted EuroScore 2 recently presented.MethodsWe reviewed all consecutive patients receiving either isolated conventional aortic valve replacement (cAVR) or transapical aortic valve implantation (TA-TAVI) in a two-year period (n = 206). 30-days mortality was considered as primary endpoint.ResultsTA-TAVI was performed in 76 patients, isolated cAVR in 130 patients. Overall mortality was 4.4% (TA-TAVI: 7.9%; cAVR: 2.3%). EuroScore 2 showed a good estimation for the entire population as well as within the subgroups: 4,02 ± 5,36% (TA-TAVI: 6.16 ± 7.14%, cAVR: 2.77 ± 3.42%). Predicted mortalities as assessed by LES were largely overestimated (TA-TAVI: 27.4 ± 20.9% cAVR: 10.6 ± 10.6%, sensitivity: 0.89, specificity: 0.71). STS predicted mortality was 6.3 ± 4.4% for TA-TAVI patients as to 3.2 ± 3.1% for cAVR patients (sens.: 0.22, spec.: 0.96) and ACEF predicted a mortality of 1.16 ± 0.36% for cAVR and 1.58 ± 0.59% for TA-TAVI patients (sens.: 0.78, spec.: 0.89).ConclusionThe newly refined EuroScore 2 showed a good correlation within the studied population. For the individual patient, new cut-offs will have to be defined to triage patients for TAVI procedure. A drawback for complex score systems such as EuroScore and STS is the lack of recalibration to smaller populations as encountered in even large single centers.

Special Treatment and Wound Care of the Driveline Exit Site after Left Ventricular Assist Device Implantation.

OBJECTIVE Despite good results following implantation of left ventricular assist devices (LVADs), infections of the driveline and device pocket remain a major problem for patients on long-term support. We present the data from heart failure patients treated with a Thoratec HeartMate-II LVAD (Thoratec Corporation, Pleasanton, California, United States). METHODS From January 2008 to April 2011, in our institution, 40 heart failure patients (NYHA IV) were supported with a HeartMate-II LVAD. The driveline maintenance of 17 patients consisted of the use of Octenidine for the wound dressing, whereas merbromin was additionally used for local irrigation in 31 patients. The data concerning driveline infections were analyzed retrospectively. RESULTS In our study, 95% of the entire cohort was free from infections of the system. Two patients in the conventional group (11.8%) developed a driveline infection at a mean of 130.5 days during 3,416 patient-days (0.21 infection/patient-years). In the Merbromid group (Co. New FaDem SRL Farmaceutici & Chimici, Giugliano, Campania, Italy), all patients were free from any driveline infections during the observation period. In a log-rank comparison, the difference reached statistical significance (p = 0.043). CONCLUSION During our observation period, fewer infections were noted with merbromin treatment. A multicenter setting in a larger cohort should be performed to confirm these findings, although a (double-) blinded setting might be difficult to achieve.

A personalized approach to interventional treatment of tricuspid regurgitation: experiences from an acute animal study

OBJECTIVES Interventional treatment of tricuspid valve disease has so far received little attention due to the anatomical challenges in a thrombogenic surrounding. In the present study, we present an imaging-based, personalized interventional approach to the therapy of tricuspid regurgitation. METHODS In our porcine model, we used rapid prototyping to build a matrix reproducing the geometry of the right atrium that was previously derived from computer tomography (CT) scans. Over this matrix, a braided nitinol device fitting almost completely the right atrium was crafted. An additional tubular stent component was developed to carry a tissue valve prosthesis. This part was designed to be connectable to the annular portion of the main device. In our feasibility study, the crimped device was implanted via jugular access into the right atrium of 12 pigs and expanded subsequently. Following isolated implantation of the device without the valve-carrying component, further procedures included implantation of the whole composite device, including the mentioned tissue valve. Representing a only feasibility study, all implantations were performed under full bypass and direct sight. On-site visualization was performed by both echocardiography and fluoroscopy. Additional imaging was realized by postoperative CT scans. RESULTS Following implantation, 9 of 12 animals were weaned from cardiopulmonary bypass. Correct positioning of the device and orthodromic blood flow as maintained by the valve prosthesis were demonstrated by echocardiography and fluoroscopy. Postoperative contrast CT evaluation demonstrated proper fitting of the device into the right-sided heart cavities without obstruction of the outflow tract. Autopsy additionally confirmed its correct positioning without major trauma to surrounding structures. CONCLUSIONS We demonstrated the feasibility in principle of a personalized interventional treatment for tricuspid regurgitation using a braided stent, based on individual cardiac imaging, with anchoring forces mainly exerted on the venae cavae and on the inner surface of the right atrium. The design process of this device is a good indicator of the growing potential of an imaging-based personalized simulation and production approach for the treatment of tricuspid valve disease.

Ultrasound-assisted treatment of sternocutaneous fistula in post-sternotomy cardiac surgery patients

OBJECTIVES Using an ultrasonic debridement system (low frequency, 25 kHz), we aimed to completely remove bacterial biofilms and preserve vital sternal tissue and to compare this procedure with conventional surgical therapy. METHODS In this retrospective study, we evaluated 37 consecutive patients (25 males) between April 2011 and June 2013 in whom sternocutaneous fistula (SCF) was treated with the ultrasound-assisted wound (UAW) system (Group A, n = 18) or with conventional surgical therapy (Group B, n = 19). Treatment in Group A consisted of a complete dissection of the SCF followed by a multistep UAW debridement session after an interval of 3 days. Our final step in both groups was secondary wound closure with a musculocutaneous flap. RESULTS Patients in both groups were categorized as high risk with respect to several of the known SCF risk factors. In both groups, a similar variety of bacteria were isolated: 61% were gram-positive species, 16.5% were gram-negative species and 10.5% were Candida albicans. Time to secondary wound closure following eradication was significantly shorter in Group A (10 ± 5.4 vs 15 ± 7.1 days in Group B, P = 0.012). Postoperative antibiotic treatment time (16 ± 9.3 vs 22 ± 10.7 days in Group B, P = 0.078) showed a trend in favour of Group A, but the mean hospitalization time (22 ± 12.0 vs 26 ± 14.3 days in Group B, P = 0.34) did not differ between groups. Recurrence of SCF tended to be less frequent in Group A (6 vs 21% in Group B, P = 0.46). In Group B, one infection-related death was noted. The mean follow-up time was 8 ± 2.7 (Group A) and 10 ± 5.7 (Group B) months. CONCLUSIONS Ultrasonic debridement is a promising adjunct to SCF treatment. In combination with adequate surgical and antimicrobial therapy, we documented good mid-term results in our trial group.

Prevention of sternal dehiscence with the Sternum External Fixation (Stern-E-Fix) corset – a randomized trial in 750 patients

BackgroundThe main objective of this study will be to determine the effects of a new advanced sternum external fixation (Stern-E-Fix) corset on prevention of sternal instability and mediastinitis in high-risk patients.MethodsThis prospective, randomized study (January 2009 – June 2011) comprised 750 male patients undergoing standard median sternotomy for cardiac procedures (78% CABG). Patients were divided in two randomized groups (A, n = 380: received a Stern-E-Fix corset postoperatively for 6 weeks and B, n = 370: control group received a standard elastic thorax bandage). In both groups, risk factors for sternal dehiscence and preoperative preparations were similar.ResultsWound infections occurred in n = 13 (3.42%) pts. in group A vs. n = 35 (9.46%) in group B. In group A, only 1 patient presented with sternal dehiscence vs. 22 pts. in group B. In all 22 patients, sternal rewiring followed by antibiotic therapy was needed. Mediastinitis related mortality was none in A versus two in B. Treatment failure in group B was more than five times higher than in A (p = 0.01); the mean length of stay in hospital was 12.5 ± 7.4 days (A) versus 18 ± 15.1 days (B) (p=0.002). Re-operation for sternal infection was 4 times higher in group B. Mean ventilation time was relatively longer in B (2.5 vs. 1.28 days) (p = 0.01). The mean follow-up period was 8 weeks (range 6 – 12 weeks).ConclusionsWe demonstrated that using an external supportive sternal corset (Stern-E-Fix) yields a significantly better and effective prevention against development of sternal dehiscence and secondary sternal infection in high-risk poststernotomy patients.

Perioperative onset of acquired von Willebrand syndrome: Comparison between HVAD, HeartMate II and on-pump coronary bypass surgery

Objectives Acquired von Willebrand syndrome (AvWS) is associated with postoperative bleeding complications in patients with continuous flow left ventricular assist devices (CF-LVADs). The aim of this study is to analyze the perioperative vWF profile comparing an axial pump (HMII) to a centrifugal pump (HVAD) regarding the correlation between perioperative occurrence of AvWS, early- and late-postoperative bleeding events. Methods From July 2013 until March 2015 blood samples of 33 patients (12 HMII/ 8 HVAD/ 13 controls) were prospectively collected at 12 different time points and analyzed for the vWF antigen (vWF:Ag), its activity (vWF:Ac) and the vWF:Ac/vWF:Ag-ratio (vWF:ratio). The follow up period for postoperative bleeding events was from July 2013 until July 2016. Results Postoperatively, there was no difference in the vWF-profile between HVAD and HMII groups. However, a subgroup of patients already had significantly lower vWF:ratios preoperatively. Postoperatively, both CF-LVAD groups presented significantly lower vWF:ratios compared to the control group. Bleeding events per patient-year did not differ between the two groups (HMII vs. HVAD: 0.67 vs. 0.85, p = 0.685). We detected a correlation between vWF:ratio <0.7at LVAD-start (r = -0.583, p = 0.006) or at the end of surgery (r = -0.461, p = 0.035) and the occurrence of pericardial tamponade. In the control group, the drop in both vWF:Ag and vWF:Ac recovered immediately postoperatively above preoperative values. Conclusion A subgroup of patients with end-stage heart failure already suffers AvWS preoperatively. In both CF-LVAD groups, AvWS begins immediately after surgery. Intraoperative vWF:ratios <0.7 correlate with higher incidences of pericardial tamponade and re-operation. The presumably dilutive effect of the heart lung machine on vWF vanishes immediately at the end of surgery, possibly as part of an acute-phase response.

Risk factors for the development of right ventricular failure after left ventricular assist device implantation—a single-centre retrospective with focus on deformation imaging

OBJECTIVES Right heart failure (RHF) after the implantation of a left ventricular assist device (LVAD) remains a dreaded postoperative complication. Using 2D speckle-tracking echocardiography, it is possible to acquire right ventricular global and regional function. The aim of our study was to assess whether speckle-tracking echocardiography values will better predict the RHF post-continuous-flow LVAD implantation. METHODS From January 2014 to January 2016, 54 patients who underwent LVAD implantation were included and retrospectively analysed. Clinical, invasive haemodynamic (right and left heart catheterization), laboratory and transthoracic echocardiography data were reviewed. Multivariable logistic regression was performed using RHF as dependent variable. RESULTS Thirteen patients (24%) developed RHF. These patients had significantly elevated procalcitonin (P = 0.011), elevated central venous pressure (CVP) pre- and post-LVAD implantation (P = 0.002 and 0.031, respectively), higher right ventricular (RV) and pulmonary systolic pressure (P = 0.016 and 0.013, respectively), higher Michigan Risk Score (P = 0.001) and a lower peak systolic longitudinal strain of the basal RV free wall (P = 0.032). Haemoglobin, procalcitonin, RV systolic pressure, basal right ventricular free wall and pre-CVP entered the final multivariable analysis, only basal right ventricular free wall (P < 0.001) and pre-CVP (P < 0.001) remained significant predictors of RHF. The sensitivity and specificity of the final model were 85.7% and 95.4%, respectively. The negative predictive value reached 94%. CONCLUSIONS 2D strain parameters of the RV free wall seem to be auspicious for RV function and predicting RHF. Moreover, intraoperative CVP should not be neglected since elevated values proved to be highly associated with RHF. Our results represent a valuable supplement to other scores by considering both echocardiography and intraoperative data.

Predictive Value of EuroSCORE II in Patients Undergoing Left Ventricular Assist Device Therapy.

Background Left ventricular assist devices (LVADs) are nowadays a widespread option for the effective treatment of heart failure. We hypothesized that the European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) might be a superior tool in clinical decision making compared with other established score systems. Methods In this retrospective, single-center analysis, between 2008 and 2014, 40 consecutive patients were followed for up to 36 months after LVAD (Thoratec HeartMate II) implantation. Postoperative survival was correlated to the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) levels, Destination Therapy Risk Score (DTRS), HeartMate II Risk Score (HMRS), and EuroSCORE II. Results Overall, a positive outcome (survival, transplantation, or weaning) was reached in 87.5% (30 days), 70% (1 year), and 60% (2 and 3 years) of cases. Patients were categorized as high, medium, and low risk by use of the different scores. Within the created subgroups, the following 1-year positive outcomes were achieved-INTERMACS: high risk 58% versus low risk 68%; EuroSCORE II: high risk 17% versus low risk 89%; DTRS: high risk 44% versus low risk 75%; and HMRS: high risk 60% versus low risk 100%. After 1 year, the EuroSCORE II classifications area under the receiver operating characteristic curve (AUC) was superior (AUC = 0.78) and Fisher exact test revealed a significant predictive value for this classification (p = 0.0037) but not for INTERMACS levels, DTRS, or HMRS classifications. Conclusion These results support the assumption that EuroSCORE II risk classification may be useful to predict survival in LVAD patients. In our observation, it proved to be superior to INTERMACS, DTRS, and HMRS after 1 year.

Inflammatory response in transapical transaortic valve replacement.

OBJECTIVE Transapical aortic valve implantation (TA-AVI) has become a fast growing alternative to conventional aortic valve replacement (cAVR) particularly for patients burdened with serious comorbidities. We investigated whether the inflammatory response triggered by TA-AVI reflects the less invasive nature of this procedure. METHOD In this prospective observational study 25 patients undergoing aortic valve replacement (AVR; 15 cAVR and 10 TA-AVI) were included. Serial plasma cytokine concentrations (IL-6, IL-8, and IL-10) were measured by commercially available enzyme-linked immunosorbent assay kits at six different time points before, during, and after surgery. RESULTS Plasma levels of all three cytokines increased during and after both procedures and returned to baseline before the patients discharge. Peak values of IL-6 were 258 ± 113 pg/mL in AVR patients versus 111 ± 101 pg/mL in TA-AVI patients and were reached 12 hours after surgery. For IL-8, peak values were 51 ± 29 pg/mL 1 hour after surgery in AVR patients versus 15 ± 20 pg/mL on wound closure in TA-AVI patients. Plasma levels of IL-6 and IL-8 were significantly reduced in the TA-AVI group as compared with cAVR. IL-10 is markedly activated in both groups yet its induction is more prominent in AVR patients with peak values of 51 ± 28 pg/mL for AVR versus 24 ± 18 pg/mL for TA-AVI on wound closure. CONCLUSION TA-AVI compared with cAVR results in a significant reduction but not elimination of a systemic inflammatory response, which is attributable to cardiopulmonary bypass-dependent and bypass-independent factors.

Sildenafil Reduces the Risk of Thromboembolic Events in HeartMate II Patients with Low-Level Hemolysis and Significantly Improves the Pulmonary Circulation

Low-level hemolysis (LLH) after left ventricular assist device implantation contributes to thromboembolic events (TE). Free plasma hemoglobin (fHb) scavenges nitric oxide (NO), which causes endothelial dysfunction and activates platelets. fHb also interacts with von Willebrand factor (vWF). We hypothesized that improved hemodynamic and enhanced NO signaling in HeartMate II (HMII) patients with LLH taking the phosphodiesterase-5 inhibitor sildenafil may reduce the risk of TE.From 2011 to 2015, 83 patients underwent HMII implantation. Patients with LLH as defined by elevated lactate dehydrogenase (400 < LDH ≤ 700 U/L) at hospital discharge were identified. Patients were categorized into 4 groups: 1) LLH + sildenafil, 2) LLH no sildenafil, 3) no LLH + sildenafil, and 4) no LLH no sildenafil. Adverse event-free survival was compared between the groups.Thirty-four patients (40.9%) were discharged with LLH and 22 (64.7%) of them took sildenafil. LDH and fHb remained significantly elevated in both LLH groups compared to the no LLH patients (P < 0.0001). Overall incidence of pump thrombosis (PT) was 4.8% and of ischemic stroke (IS) was 8.4%. HMII patients with LLH not on sildenafil had higher risk of TE (hazard ratio (HR): 14.4, 95%-CI: 1.8-117.1, P = 0.001). vWF activity and bleeding incidence did not differ between the LLH and no LLH patients. Mean pulmonary artery pressure and pulmonary vascular resistance decreased significantly in HMII taking sildenafil (P < 0.0001) while cardiac index increased (P < 0.0001).Sildenafil treatment among HMII patients with LLH reduced the risk of thromboembolic events and significantly improved and decompressed the pulmonary circulation during HMII support.