A multicenter evaluation of external outflow graft obstruction with a fully magnetically levitated left ventricular assist device

BACKGROUND

The HeartMate 3 (HM 3; Abbott) left ventricular assist device (LVAD) has improved hemocompatibility-related adverse outcomes. In sporadic cases, external compression of the outflow graft causing obstruction (eOGO) can result from substance accumulation between the outflow graft and its bend relief. We sought to evaluate the prevalence, course, and clinical implications of eOGO in an international study.

METHODS

A multicenter retrospective analysis of HM 3 LVADs implanted between November 2014 and April 2021 (n = 2108) was conducted across 17 cardiac centers in 8 countries. We defined eOGO as obstruction >25% in the cross-sectional area in imaging (percutaneous angiography, computed tomography, or intravascular ultrasound). The prevalence and annual incidence were calculated. Serious adverse events and outcomes (death, transplantation, or device exchange) were analyzed for eOGO cases.

RESULTS

Of 2108 patients, 62 were diagnosed with eOGO at a median LVAD support duration of 953 (interquartile range, 600-1267) days. The prevalence of eOGO was 3.0% and the incidence at 1, 2, 3, 4, and 5 years of support was 0.6%, 2.8%, 4.0%, 5.2%, and 9.1%, respectively. Of 62 patients, 9 were observed, 27 underwent surgical revision, 15 underwent percutaneous stent implantation, 8 received a heart transplant, and 2 died before intervention. One patient underwent surgical revision and later stent implantation. The mortality with therapeutic intervention was 9/53 (17.0%).

CONCLUSIONS

Although uncommon, HM 3 LVAD-supported patients might develop eOGO with an increasing incidence after 1 year of support. Although engineering efforts to reduce this complication are under way, clinicians must maintain a focus on early detection and remain vigilant.

Driveline infections in left ventricular assist devices-Incidence, epidemiology, and staging proposal

BACKGROUND

Driveline infections (DLI) are a serious complication in patients with left ventricular assist devices (LVAD). Apart from the differentiation between superficial and deep DLI, there is no consensus on the classification of the severity of DLI. Little is known about risk factors and typical bacteria causing DLI in centrifugal-flow LVADs.

METHODS

In this single-center study with 245 patients, DLI were classified by their local appearance using a modification of a score suggested by the Sharp Memorial group. The driveline exit site was inspected routinely every 6 months.

RESULTS

Severe DLI were detected in 34 patients (15%) after 6 months and in 24 patients (22%) after 24 months. The proportion of patients with DLI increased significantly during the follow-up (p = 0.0096). The most common bacteria in local smears were Corynebacterium, coagulase-negative Staphylococcus, and Staphylococcus aureus. Fifty-nine patients were hospitalized more than once for DLI. In these patients, S. aureus was the most common bacterium. It was also the most common bacterium in blood cultures. Higher BMI, no partnership, and a HeartMate 3 device were identified as risk factors for DLI in a multivariable cause-specific Cox regression.

CONCLUSION

This study is a standardized analysis of DLI in a large cohort with centrifugal-flow LVADs.

Insights into the daily life of ventricular assist device coordinators: Outcome of an international questionnaire

BACKGROUND

As the incidence of heart failure in developed countries is on the rise, mechanical circulatory support (MCS) often remains the only treatment option for patients with end-stage heart failure and is well established worldwide. Even though VAD coordinators play a key role in VAD programs, their responsibilities and daily duties are not clearly defined and characterized. Recently published data from the first 5-year multicenter clinical trial assessing experience with the HeartMate 3 left ventricular system (Abbott, Abbott Park, IL) show an overall survival of 61% at 5 years. When it comes to possible improvements to these systems, it is necessary for developers not only to know the status quo but also to determine and consider the visions and wishes of those individuals who take care of patients, provide education and deal with possible complications. This would be helpful a meaningful effort towards implementing a standard of care.

METHODS

To fill this knowledge gap, we conducted an online survey using the SurveyMonkey tool, addressing representatives of programs implanting VADs worldwide. Representatives answered a standardized block of 14 questions and were asked to provide responses within 3 months.

RESULTS

A total of 91 VAD coordinators from centers of various regions of the world completed the survey. The majority came from European countries. The numbers of patients followed up by the centers ranged from <20 to 390 patients. The majority of VAD coordinators had a nursing background (68%). Seventy-seven percent of the centers operate a 24-h hotline and 3-monthly visits to the outpatient department are most common. Fifty-nine percent of the centers do not use an infection scoring system for driveline wound care. The majority of the centers indicated that an optimized follow-up concept including wound care, medication, and social care is crucial and the key issue for an improved outcome. Smaller components and intensified psychosocial support ranked highest in questions about how to improve quality of life. Surprisingly, the future prospects of telemetric monitoring were not rated high in significance.

CONCLUSIONS

There is a wide variability in the composition and tasks of VAD programs worldwide. Implementing a standard of care and improving psychosocial care as well as equipment is regarded most important to improve outcomes and quality of life. From the point of view of those responsible, the significance of telemetric monitoring seemed overrated.

Severe pulmonary valve insufficiency caused by transjugular cannulation of pulmonary artery for right ventricular assist device: diagnosis and surgical solution-a case report

Implantation of a temporary percutaneous right ventricular assist device (RVAD) in patients with right heart failure after left ventricular assist device (LVAD) implantation is an established technique that may cause complications. We present a 60-year-old male patient who underwent urgent LVAD implantation. On the second postoperative day the patient developed acute right heart failure. We implanted a temporary percutaneous RVAD with two cannulas via the right internal jugular vein and the right femoral vein. Transesophageal echocardiography revealed severe pulmonary insufficiency. After performing re-sternotomy we anastomosed a prosthetic graft to the pulmonary trunk (PT), performed subxiphoid tunneling of the graft and replaced the transjugular outflow cannula. The pulmonary regurgitation caused by the percutaneous transvalvular cannula disappeared. In such case a direct anastomosis to the PT is the solution.

Results of non-elective withdrawal of continuous-flow left ventricular assist devices in selected patients

BACKGROUND

Protocols have been developed to identify patients for elective withdrawal of continuous-flow left ventricular device (cfLVAD) support. However, little is known about non-elective explantation or decommissioning of cfLVADs.

METHODS

A retrospective analysis of all patients who underwent left ventricular assist device (LVAD) explantation or decommissioning at a single center between 2002 and 2021 was performed.

RESULTS

Sixty-one patients underwent withdrawal of a cfLVAD (HeartMate II [Abbott] n = 17, HeartMate 3 [Abbott] n = 2, HeartWare HVAD [Medtronic] n = 36, INCOR [Berlin Heart] n = 6). The median follow-up after withdrawal was 1,039 days. The survival at 5 years was 76.1% (95% CI: 64.2%-95.2%). Predictors of worse outcomes in univariate regressive analysis were the duration of heart failure and the age at LVAD implantation. Of the 61 patients, 40 underwent elective withdrawal following a specific protocol. The other twenty-one patients underwent non-elective withdrawal of the cfLVAD because of device infection (n = 12), device thrombosis (n = 6), device malfunction (n = 2) or due to acute intracerebral bleeding (n = 1), also with an excellent survival at 5 years of 81.3%. (95% CI: 63.8-1). The withdrawal was performed in these patients even though they did not fulfill established criteria for successful explantation or decommissioning like clinical stability (n = 21), left ventricular end-diastolic diameter ≤ 55 mm (n = 3), performance of right heart catheterization (n = 6), or pulmonary artery wedge pressure ≤ 15 mm Hg (n = 3).

CONCLUSION

Non-elective withdrawal is possible in selected patients after discussion in a team of experienced cardiac surgeons, cardiologists, technicians, and VAD coordinators. The appropriate preoperative assessment before decommissioning or explantation of a cfLVAD warrants further investigation.

Left Ventricular Assist Device Implantation in Cancer-Therapy-Related Heart Failure

Objectives: Cancer-therapy-related heart failure (CTrHF) due to cardiotoxic drugs or radiation is a growing cause of end-stage heart failure. Limited knowledge is available concerning the use of continuous-flow left-ventricular-assist devices (cfLVAD) in this setting. Methods: The files of all 1334 patients who underwent cfLVAD implantation between December 2008 and December 2020 were screened for the cause of heart failure. All patients with CTrHF were included in the analysis. Results: A total of 32 patients with a median age of 58 years (IQR: 46–65) were included in the study; 15 (47%) were male. The median time from the first diagnosis of heart failure (HF) to cfLVAD implantation was 6 months (IQR 2–24), and from cancer treatment to cfLVAD implantation 40 months (IQR 5–144). Malignancies comprised non-Hodgkin lymphoma (n = 12, 37%), breast cancer (n = 9, 28%), sarcoma (n = 5, 16%), leukemia (n = 5, 16%), and others (n = 1, 3%). In 24 patients, chemotherapy included anthracyclines (others n = 2, unknown n = 6). Chest radiation was performed in 13 patients (39%). Moreover, 71% were classified as INTERMACS profile 1 or 2. The 30-day survival rate after LVAD implantation was 88%. Rethoracotomy was necessary in nine (29%), and a temporary right ventricular assist device in seven (21%) patients. The median survival was 29 months. There was no significant difference in survival or right HF between patients with CTrHF and a matched control group. Conclusions: CfLVAD implantation is feasible in high-risk patients with CTrHF with or without prior chest radiation.

Cardiac remodeling in patients with centrifugal left ventricular assist devices assessed by serial echocardiography

AIM

The aim of the study was to characterize the remodeling process in a large cohort of patients supported with a centrifugal left ventricular assist device (cfLVAD) by standardized serial echocardiography.

METHODS AND RESULTS

From 3/2018 all cfLVAD patients underwent transthoracic echocardiography at 6 and 12 months after implantation using a standardized protocol. A total of 512 echocardiograms were reviewed (216 preoperative, 156 at 6 months, 140 at 12 months). While on cfLVAD support, left ventricular (LV) diameter decreased (p < .001). LV ejection fraction (LVEF) and LV fractional area change improved (p < .001). Potential for cfLVAD explantation (as defined by an LVEF ≥45% and opening of the aortic valve [AV]) was seen in nine patients at 6 and 21 patients at 12 months. The tricuspid annular excursion decreased significantly, while the right ventricular fractional area change did not change. Tricuspid regurgitation (TR) and mitral regurgitation (MR) improved significantly during LVAD support. Opening of the AV was seen in >64% of the patients at 6 months and in 66% at 12 months. Moderate aortic regurgitation (AR) was rare with 3.8% at 6 months but increased with the duration of cfLVAD support (8.5% at 12 months). We found no significant difference in echocardiographic parameters between patients supported with a HeartWare HVAD™ or a HeartMate 3™ device.

CONCLUSION

LVAD therapy can lead to reverse LV remodeling and improvement of MR and TR. However, right ventricular function does not improve and prevalence of AR progressively increases during mechanical support.

Comparison of feasibility and results of frailty assessment methods prior to left ventricular assist device implantation

AIMS

Assessing frailty and sarcopenia is considered a valuable cornerstone of perioperative risk stratification in advanced heart failure patients. The lack of an international consensus on a diagnostic standard impedes its implementation in the clinical routine. This study aimed to compare the feasibility and prognostic impact of different assessment tools in patients undergoing continuous-flow left ventricular assist device (cf-LVAD) implantation.

METHODS AND RESULTS

We prospectively compared feasibility and prognostic values of six frailty/sarcopenia assessment methods in 94 patients prior to cf-LVAD implantation: bioelectrical impedance analysis (BIA), computed tomography (CT)-based measurement of two muscle areas/body surface area [erector spinae muscle (TMESA/BSA) and iliopsoas muscle (TPA/BSA)], physical performance tests [grip strength, 6 min walk test (6MWT)] and Rockwood Clinical Frailty Scale (RCFS). Six-month mortality and/or prolonged ventilation time >95 h was defined as the primary endpoint. BIA and CT showed full feasibility (100%); physical performance and RCFS was limited due to patients' clinical status (feasibility: 87% grip strength, 62% 6MWT, 88% RCFS). Phase angle derived by BIA showed the best results regarding the prognostic value for 6 month mortality and/or prolonged ventilation time >95 h (odds ratio (OR) 0.66 [95% confidence interval (CI): 0.46-0.92], P = 0.019; area under the curve (AUC) 0.65). It provided incremental value to the clinical risk assessment of EuroSCORE II: C-index of the combined model was 0.75 [95% CI; 0.651-0.848] compared with C-index of EuroSCORE II alone, which was 0.73 (95% CI: 0.633-0.835). Six-month survival was decreased in patients with reduced body cell mass derived by BIA or reduced muscle area in the CT scan compared with patients with normal values: body cell mass 65% (95% CI: 51.8-81.6%) vs. 83% (95% CI: 74.0-93.9%); P = 0.03, TMESA/BSA 65% (95% CI: 51.2-82.2%) vs. 82% (95% CI: 73.2-93.0%); P = 0.032 and TPA/BSA 66% (95% CI: 53.7-81.0%) vs. 85% (95% CI: 75.0-95.8%); P = 0.035.

CONCLUSIONS

Bioelectrical impedance analysis parameters and CT measurements were shown to be suitable to predict 6-month mortality and/or prolonged ventilation time >95 h in patients with advanced heart failure prior to cf-LVAD implantation. Phase angle had the best predictive capacity and sarcopenia diagnosed by reduced body cell mass in BIA or muscle area in CT was associated with a decreased 6 month survival.

Impact of left ventricular inspection employing cardiopulmonary bypass on outcome after implantation of left ventricular assist device

BACKGROUND

Cardiopulmonary bypass (CPB) during left ventricular assist device (LVAD) implantation provides circulatory support and allows for safe inspection of the left ventricle (LV), whereas circulatory support by veno-arterial extracorporeal life support (va-ECLS) or off-pump implantation may reduce postoperative bleeding and inflammatory response.

METHODS

Retrospective analysis of 616 consecutive adult patients who received an LVAD via median sternotomy between January 1, 2015 and December 31, 2019. All patients undergoing concomitant intracardiac procedures other than closure of persistent foramen ovale or atrial septal defect and redo surgeries were excluded from the analysis. The remaining patients (n = 222) were divided into two groups and 1:1 propensity score-matched regarding preoperative parameters: patients who underwent LVAD implantation with LV inspection employing CPB (CPB group, n = 62) and without LV inspection on va-ECLS or off-pump (non-CPB group, n = 62).

RESULTS

The groups were well balanced with regard to preoperative baseline characteristics (standard difference <0.1). Patients in the CPB group required more blood transfusions (median 2 vs. 0 units, p = 0.031) during surgery and in the first 24 h afterwards. The median intensive care unit stay was longer in the CPB group (18 vs. 11 days, p = 0.021). The CPB group showed an absence of perioperative stroke and a smaller number of events per patient-year for postoperative ischemic stroke (0.02 vs. 0.12, p = 0.003). 30-day survival (87% vs. 87.1%) and 1-year survival (80.3% vs. 74%) were similar in both groups (p = 0.78).

CONCLUSION

Visual LV inspection on CPB may reduce the risk of postoperative ischemic stroke. Despite the negative effects of employing CPB in lieu of other intraoperative strategies, survival was similar in both groups.

Treatment of chronic left ventricular assist device infection with local application of bacteriophages

Left ventricular assist device-associated infections represent a major complication during long-term support. Driveline exit site infections harbour the risk of ascending into the pump, causing deep-seated infections. We report on the successful treatment of a chronic recurrent left ventricular assist device pump-associated infection by the local application of bacteriophages as adjunct to standard surgical and antimicrobial treatment.

Retrospective 1-year outcome follow-up in 200 patients supported with HeartMate 3 and HeartWare left ventricular assist devices in a single centre

OBJECTIVES

Various trials have assessed the outcome and reliability of the HeartWare HVAD (HW) and HeartMate 3 (HM3) left ventricular assist devices. A direct comparison of clinical outcomes and of the complication profile of these 2 left ventricular assist devices is lacking. We present a retrospective analysis of patients supported with HM3 and HW as a left ventricular assist device.

METHODS

Preoperative data, complications and outcomes including a 1-year follow-up of patients supported with the HM3 and HW in a single centre were retrospectively analysed. Both pumps were implanted on- or off-pump, employing standard and minimally invasive techniques. For logistic reasons, the 2 device types were implanted in an alternating manner, thereby reducing the systematic bias for pump selection. We considered this to be an appropriate approach, as no differences in respect of survival or the complication profile of the two device types have been demonstrated. Anticoagulation was similar in patients with both pumps according to our anticoagulation protocol, with a target international normalized ratio of 2.5-3.0, a home monitoring system and blood pressure management with a mean arterial target pressure of 70-80 mmHg.

RESULTS

Between October 2015 and April 2017, 100 patients underwent implantation of the HW and 100 patients underwent implantation of the HM3. The median time on the device was 0.98 years (range 0-2.23 years). The median age was 58.5 (51-65) versus 57 (49-64) years (P = 0.456); the number of male patients was 87 versus 88 (P = 0.831). Of the HW patients, 73% were rated as having an INTERMACS level I or II, compared to 57% of the HM3 patients (P = 0.018). There were no further differences in preoperative data. A total of 14 patients had pre-, intra- or post-pump blood flow obstruction in the HW group versus 4 in the HM3 group [hazard ratio (HR) 2.5 (0.7-8.8), P = 0.103]. There were no differences regarding gastrointestinal bleeding [HR 1.25 (0.56-2.64), P = 0.624] or driveline infection (0.68 vs 0.8 events per patient-year, P = 0.0789). The incidence of ischaemic stroke was similar in both groups [HR 0.72 (0.25-2.09), P = 0.550]. Cerebral bleeding was more frequent in patients supported with HW [HR 6.79 (1.43-32.20), P = 0.016]. The incidence of cerebrovascular accidents, on the other hand, was similar in both groups [HR 1.85 (0.83-4.19), P = 0.13]. The incidence of haemocompatibility-related adverse events, however, was significantly higher in the HW group (113 points corresponding to 1.28 events per patient-year versus 69 points corresponding to 0.7 events per patient-year, P < 0.001). The 1-year survival was similar in both groups [62.2%, 95% confidence interval (CI) (0.53-0.73) vs 66.7%, 95% CI (0.58–0.767) [corrected].

CONCLUSIONS

Our data show that the complication profile differs between the 2 pumps, but that early survival is comparable.

Safety of Contemporary Heart Failure Therapy in Patients with Continuous-Flow Left Ventricular Assist Devices

BACKGROUND

Limited data are available concerning the safety, optimal administration and benefits of contemporary heart failure therapy in patients after left ventricular assist device (LVAD) implantation.

METHODS

Between 2015 and 2019, 257 patients underwent LVAD implantation and were included in this observational study. Oral heart failure therapy was initiated and uptitrated during the further course. After propensity matching and excluding patients with immediate postoperative treatment in an affiliated center with different medical standards, hospitalization rates and mortality within 12 months after LVAD implantation were compared between 83 patients who received medical therapy including an angiotensin receptor neprilysin inhibitor (ARNI) and 83 patients who did not receive an ARNI.

RESULTS

The overall use of heart-failure medications after 12 months was high: prescriptions: beta-blockers, 85%; angiotensin inhibiting drugs, 90% (angiotensin-converting-enzyme inhibitors 30%, angiotensin receptor blockers 23%, ARNI 37%); mineralocorticoid receptor antagonists, 80%. No serious drug-related adverse events occurred. The conditional 1-year survival in the group with ARNIs was 97% (95% CI: 94%-100%) compared to 88% in the group without an ARNI (95% CI: 80%-96%); P = 0.06.

CONCLUSIONS

Contemporary heart failure therapy is safe in patients with LVADs. No increase in serious adverse events was seen in patients receiving ARNIs. No significant difference in the conditional 1-year survival was seen between the ARNI group and the nonARNI group.

Durable mechanical circulatory support in patients with heart failure with preserved ejection fraction

Only few patients with heart failure with preserved ejection fraction undergo durable mechanical circulatory support implantation. We identified three patients with heart failure with preserved ejection fraction who needed durable mechanical circulatory support as bridge-to-transplant therapy. In two patients with hypertrophic cardiomyopathy, the hypertrophic papillary muscles and myocardium were resected to allow for subsequent left ventricular assist device implantation. In one patient, all visible parts of the mitral valve were additionally resected. The third patient with restrictive cardiomyopathy underwent Berlin Heart Excor BVAD implantation with left atrial cannulation.

Development of tricuspid regurgitation and right ventricular performance after implantation of centrifugal left ventricular assist devices

Background

Tricuspid regurgitation (TR) after left ventricular assist device (LVAD) implantation is associated with a poor prognosis. This study evaluates the development of TR and right ventricular (RV) performance after LVAD implantation.

Methods

Retrospective analysis of patients who underwent LVAD implantation between March 2018 and June 2019. Patients who underwent concomitant tricuspid valve surgery and patients with congenital heart disease were excluded.

Results

A total of 155 patients underwent LVAD implantation. Fourteen patients were excluded. Of the remaining patients, thirty-one died during the first six months, six were lost to follow-up and two underwent transplantation. 102 patients presented at 6.3 months (5.8 to 7.0). Patients were supported with HeartWare HVAD (74%) or HeartMate 3 (26%). 50.4% were rated as INTERMACS profile 1 or 2. At six months, systolic pulmonary artery pressure dropped from 36 to 21 mmHg (P<0.001). Tricuspid annular plane systolic excursion decreased from 17.3 to 14.3 mm (P<0.001), RV fractional area change did not change (P=0.839). Twenty-two patients (22%) presented with moderate-to-severe or severe (ms-s) TR pre-operatively. Of these, eighteen (81%) showed improvement to ≤ moderate TR. At follow-up twelve patients presented with ms-s TR. Of these, only four patients (33%) had been diagnosed with ms-s TR pre-operatively. There were no differences in pre-operative echocardiographic or clinical parameters between the twelve patients with ms-s late TR and the other ninety patients in the cohort.

Conclusions

TR can show an impressive improvement with LVAD support. Longitudinal RV function decreases; this appears to be compensated by transverse shortening. Late TR can develop independently from pre-operative parameters including TR.

Experience with a standardized protocol to predict successful explantation of left ventricular assist devices

OBJECTIVE

Patients with a continuous-flow left ventricular assist device may show recovery of myocardial function with unloading. Identifying candidates for and predicting clinical and hemodynamic stability after left ventricular assist device explantation remain challenging.

METHODS

Retrospective analysis of patients who underwent evaluation for left ventricular assist device explantation following a standardized protocol from January 2016 to March 2020. Patients who met screening criteria underwent echocardiography under "baseline," "minimal net flow," and "pump stop" conditions. If the protocol criteria were met, right heart catheterization with left ventricular assist device stoppage and occlusion of the outflow graft with a balloon catheter were performed. In patients with pulmonary capillary wedge pressure less than 16 mm Hg, explantation was performed under "pump stop" conditions.

RESULTS

A total of 544 patients were screened. Of these, 57 (10.5%) underwent a total of 73 echocardiography under "baseline" "minimal net flow" and "pump stop" conditions and 46 underwent left ventricular assist device stoppage and occlusion of the outflow graft with balloon catheter maneuvers. Complications during the procedure were rare. Ultimately, 21 patients (3.9%) underwent explantation. The left ventricular ejection fraction at baseline was 55.5% ± 6.5%. The mean pulmonary capillary wedge pressure was 8.1 ± 2.6 mm Hg and increased to 10.7 ± 2.9 mm Hg under left ventricular assist device stoppage and occlusion of the outflow graft with a balloon catheter. A nonischemic cause of cardiomyopathy was more likely to be found in patients who underwent explantation (20/21 patients [95%], P = .020). The survival 1 year after explantation was 95.2%, with 1 death occurring 222 days after left ventricular assist device explantation. At follow-up (median 24.9 months [interquartile range, 16.4-43.1 months]), patients were in New York Heart Association class 1 (61.9%), 2 (28.6%), and 3 (9.5%).

CONCLUSIONS

Our 4-year experience with a standardized protocol for left ventricular assist device explantation showed a low rate of adverse events. If all criteria are met, explantation can be performed safely and with an excellent survival and functional class.

Safety of bioelectrical impedance analysis in advanced heart failure patients

BACKGROUND

Cardiac cachexia and frailty are major complications of advanced heart failure (AHF). Bioelectrical impedance analysis (BIA) may provide valuable information regarding fluid balance, muscle mass and prognosis. The main concerns regarding the use of BIA in AHF patients remain arrhythmias and electromagnetic interferences with cardiac implantable electronic devices (CIEDs). Reliable data regarding patients on continuous-flow ventricular assist device (cf-VAD) remain scarce. The aim of this study is to evaluate the safety of BIA in AHF patients on pro-arrhythmogenic therapy with an implanted CIED and/or with a cf-VAD.

METHODS

We prospectively performed 217 BIA measurements in 143 AHF patients at risk of severe arrhythmias due to inotropic support/a history of ventricular arrhythmias and/or treated with CIED, including 104 patients with an ICD, CRT or pacemaker and 95 patients with a cf-VAD. All patients were under continuous Electrocardiogram (ECG) monitoring and clinical surveillance for 24 hours.

RESULTS

No adverse events were observed during the 217 BIA measurements: No rhythm disturbances were documented in the telemetric monitoring during or within 30 minutes after the measurement. CIEDs showed no malfunction, regardless of the location measured or the device manufacturer. In particular, no inappropriate shocks were observed. No alarms, flow disturbances, or malfunctions of the cf-VAD occurred during or after the measurements.

CONCLUSION

We consider BIA a safe measurement with major clinical relevance in our cohort of AHF patients, despite an increased arrhythmic potential on inotropic support or the presence of implanted electronic devices (ICD, CRT, pacemaker and cf-VAD).

Temporary mechanical circulatory support for refractory heart failure: the German Heart Center Berlin experience

Background

Temporary mechanical circulatory support (MCS) offers a valuable option for treatment of refractory heart failure. We present our experience with selected MCS devices in cardiogenic shock of different etiologies.

Methods

We retrospectively studied patients who were treated in our institution between 01/2016 and 07/2018. Patients receiving only veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support were excluded. Left ventricular support patients received Impella; right ventricular support was conducted using Levitronix CentriMag.

Results

Thirty-seven patients received an Impella left ventricular assist device (LVAD). Etiology was: acute on chronic ischemic cardiomyopathy (ICMP; n=12), acute myocardial infarction (AMI; n=11), dilated cardiomyopathy (DCMP; n=7) and toxic cardiomyopathy (TCMP; n=2). Two patients presented with postcardiotomy shock and acute myocarditis, respectively. In one case, Takotsubo cardiomyopathy was diagnosed. Impella was used solely in 28 patients (Impella group) with an in-hospital survival of 37%. In nine patients, Impella was used in combination with extracorporeal life support (ECLS) implantation (ECMELLA group)-in-hospital survival was 33%. In the Impella group six patients recovered, six received a long-term VAD and 16 died on device. In the ECMELLA group one patient recovered, three received a long-term VAD and five died. The majority of CentriMag implantations as a right ventricular assist device (RVAD) were necessary after LVAD implantation (n=52); of these patients, 14 recovered, eight received long-term VAD and 30 died. The remaining 17 patients were supported by RVAD due to AMI (n=7); postcardiotomy (n=7); right heart failure after heart transplantation (n=2) and ICMP (n=1). Six of these patients recovered, two required long-term VAD and nine died.

Conclusions

Survival after MCS implantation for left as well as right heart failure in cardiogenic shock remains low, but is superior to that of patients without mechanical support. Short-term MCS remains an option of choice if right, left or biventricular support is needed.

Outcomes from a recovery protocol for patients with continuous-flow left ventricular assist devices

BACKGROUND

In this retrospective analysis we evaluated a standardized echocardiographic assessment and an invasive technique for patient selection for successful continuous-flow left ventricular assist device (CF-LVAD) explantation.

METHODS

Inclusion criteria for LVAD recovery assessment were: clinically stable condition; LVAD support for >6 months; physical activity; normal echocardiography findings; and no more than mild valvular disease and aortic valve opening. In a second step, echocardiography was performed under CF-LVAD reduction and stop conditions (PStopE). In the third step, patients who presented with stable parameters underwent right heart catheterization under CF-LVAD stoppage and occlusion of the outflow graft with a balloon catheter. Criteria for explantation were normal pulmonary artery pressure and pulmonary capillary wedge pressure <16 mmHg.

RESULTS

Thirty-three of 424 patients entered the second step of evaluation and 20 entered the third step. Fourteen presented positive results and the pump was successfully explanted. The PCWP at baseline was 8.5 (2.8) mmHg in the explantation group and 10.6 (2.8) mmHg in the non-explantation group (p = 0.105). It increased to 10.9 (3.0) mmHg vs 20.8 (4.9) mmHg under outflow graft occlusion. The wedge pressure was significantly higher in the non-explantation group (p < 0.001). Median duration of follow-up after explantation was 9.74 (interquartile range 4.3 to 20.60) months, with survival of 93%.

CONCLUSIONS

The protocol presented is feasible and safe. The criteria applied provide good patient selection for sustained mid-term myocardial recovery after LVAD explantation.

The Hydrophobic Mannose Derivative 1B6TM Efficiently Inhibits Borna Disease Virus in Vitro

α-D-Mannnose occupies the terminal position on the N-linked carbohydrate side chain of BDV-specific gp17 (Stoyloff et al., 1994). A hydrophobic derivative of this sugar residue, the 1-0-benzyl-6-0-trityl-α-D-mannnopyranoside (1B6TM), showed a potent and selective inhibition of BDV-replication in vitro, using a range of host-cell/virus systems. When tested in comparison with the unmodified sugar, 1B6TM inhibited the infection in a dose-dependent manner up to 100% without effecting cell viability. After removal of the compound, the antiviral effect remained for several hours. These results suggest that simple modified carbohydrate molecules of BDV-specific sugar residues are able to interfere with virus replication.

Valerenic acid derivatives as novel subunit-selective GABAA receptor ligands - in vitro and in vivo characterization

BACKGROUND AND PURPOSE

Subunit-specific modulators of gamma-aminobutyric acid (GABA) type A (GABA(A)) receptors can help to assess the physiological function of receptors with different subunit composition and also provide the basis for the development of new drugs. Valerenic acid (VA) was recently identified as a beta(2/3) subunit-specific modulator of GABA(A) receptors with anxiolytic potential. The aim of the present study was to generate VA derivatives as novel GABA(A) receptor modulators and to gain insight into the structure-activity relation of this molecule.

EXPERIMENTAL APPROACH

The carboxyl group of VA was substituted by an uncharged amide or amides with different chain length. Modulation of GABA(A) receptors composed of different subunit compositions by the VA derivatives was studied in Xenopus oocytes by means of the two-microelectrode voltage-clamp technique. Half-maximal stimulation of GABA-induced chloride currents (I(GABA)) through GABA(A) receptors (EC(50)) and efficacies (maximal stimulation of I(GABA)) were estimated. Anxiolytic activity of the VA derivatives was studied in mice, applying the elevated plus maze test.

KEY RESULTS

Valerenic acid amide (VA-A) displayed the highest efficacy (more than twofold greater I(GABA) enhancement than VA) and highest potency (EC(50)= 13.7 +/- 2.3 microM) on alpha(1)beta(3) receptors. Higher efficacy and potency of VA-A were also observed on alpha(1)beta(2)gamma(2s) and alpha(3)beta(3)gamma(2s) receptors. Anxiolytic effects were most pronounced for VA-A.

CONCLUSIONS AND IMPLICATIONS

Valerenic acid derivatives with higher efficacy and affinity can be generated. Greater in vitro action of the amide derivative correlated with a more pronounced anxiolytic effect in vivo. The data give further confidence in targeting beta(3) subunit containing GABA(A) receptors for development of anxiolytics.

Advanced anorexia nervosa, associated with pneumomediastinum, pneumothorax, and soft-tissue emphysema without esophageal lesion

OBJECTIVE

We describe the case of a 20-year-old female patient suffering from anorexia nervosa since the age 15 of years. When admitted, she was 168 cm tall with a weight of 35 kg (body mass index [BMI] = 12.4). A week after admission, the patient complained of retrosternal pain, and a few hours later she developed extensive soft-tissue emphysema.

METHODS

The X-ray picture of her thorax showed left-hand supraclavicular and infraclavicular emphysema, extensive emphysema in both sides of the soft tissue of the throat, a left-hand apical pneumothorax (4 mm), and a pneumomediastinum.

RESULTS

We discuss the extent to which these symptoms are interrelated in the sense of a causal nexus.

CONCLUSION

We ruled out any other differential-diagnostic etiopathogenic factors and concluded that the cause of our patient's soft-tissue emphysema, pneumothorax, and pneumomediastinum might well be autodestructive behavior.

Evaluation der Abbildungsqualität unterschiedlicher Befundungsmodalitäten in der digitalen Radiologie

PURPOSE

To evaluate the display quality of digital radiographies on different monitors in comparison to hard-copy films on view boxes.

MATERIALS AND METHODS

Radiographs of different statistical phantoms simulating common pathologies of the chest, such as interstitial pneumonia, pneumothorax and pulmonary nodules, were acquired. Under same ambient light condition, the radiographs were rated as to the presence or absence of a simulated pathological finding using a confidence scale. The evaluation was performed on a grey-scale monitor, a color monitor, two LC displays and two different light boxes by four experienced radiologists. Sensitivity and specificity were determined in a ROC analysis for each viewing modality and phantom. The area under the curve (Az) was acquired cumulatively including the results of all investigators. A total of 4200 rating decisions were included. The chi (2)-test was performed for significance analysis using the a and b parameters of two ROC-curves (alpha = 0.05).

RESULTS

The rating of the included LC displays (Az = 0.7009 - 0.9608) and color monitors (Az = 0.7993 - 0.9591) showed a significant loss of diagnostic validity in comparison to the grey-scale monitor (Az = 0.8435 - 0.9762) and the view boxes (Az = 0.8228 - 0.9891).

CONCLUSION

LC displays and color monitor included in this study cannot be recommended for diagnostic viewing. The loss of diagnostic validity might be attributable to the viewing-angle-dependent contrast of LC displays. However, no loss in diagnostic validity could be assessed for the tested grey-scale monitor.

Synthesis and acetylcholinesterase inhibition of 5-desamino huperzine A derivatives

(E)- and (Z)-5-Desamino huperzine A derivatives have been synthesized using a new synthetic strategy towards the huperzine A skeleton. These derivatives showed AChE inhibition constants in the low micromolar range and thus display better activity than all previously synthesized C5 derivatives.

The 12,13-diol cyclization approach for a truly stereocontrolled total synthesis of epothilone B and the synthesis of a conformationally restrained analogue

A highly convergent and stereocontrolled synthesis of epothilone B (1) has been developed. The epoxide moiety in 1 was generated by regioselective mesylation and base treatment of the 12,13-diol 30 which was formed by a chelate Cram controlled Grignard addition of 14 and methyl ketone 13. Both fragments were synthesized from the chiral carbon pool precursors (S)-citronellol and (S)-lactic acid, respectively. A highly diastereoselective aldol addition of epoxy-aldehyde 7 and the known Southern hemisphere ketone 8 delivered the full carbon skeleton, containing all the stereogenic centers of 1. Functional group manipulation, macrolactonization and removal of two protecting groups then yielded 1. The spatial closeness of the C4-beta-methyl and C6-methyl group in the crystal structure of 1 inspired us to connect them through a methylene bridge to give a cyclohexanone derivative. Thus, the Northern hemisphere aldehyde 7 was added to the enolate of the cyclohexanone 47. Further manipulations and macrolactonization delivered the conformationally restrained epothilone derivative 42.

A novel palladium-catalyzed intramolecular redox reaction

[reaction: see text] A new type of palladium-catalyzed redox reaction is described, forming enones from 2-(2-bromobenzyl)-ketones with an overall loss of HBr. The scope and limitations of the reaction are demonstrated by a series of cyclic and acyclic substrates. The mechanism most probably involves the formation of an intramolecular arylpalladium enolate and is related to the oxidation of silyl enol ethers with palladium acetate.

Total syntheses of epothilones B and D

Total syntheses of the microtubule stabilizing antitumor drugs epothilone B and D are described, starting from optically pure (S)-malic acid and methyl (R)-3-hydroxy-2-methylpropionate. The synthesis is highly convergent by coupling the three fragments C1-C6 (fragment D), C7-C10 (fragment C), and C11-C21 (fragment B). Key steps are two stereoselective Wittig type olefinations to generate the 12,13- and 16,17-double bonds, an enantioselective Mukaiyama aldol addition to synthesize fragment D, and a sulfone anion allyl iodide alkylation to connect fragments B and C. Finally fragment D was attached to the B + C fragment via aldol addition.