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.

Fully magnetically centrifugal left ventricular assist device and long-term outcomes: the ELEVATE registry

BACKGROUND AND AIMS

HeartMate 3 (HM3) is a fully magnetically levitated continuous flow left ventricular assist device, which received CE marking in 2015. The ELEVATE Registry was initiated to collect real-world outcomes in patients treated with HM3 post-CE Mark approval.

METHODS

A total of 540 subjects implanted at 26 centres between March 2015 and February 2017 were included in this registry. Of these, 463 received the device as a primary implant (primary implant cohort, PIC), 19 as a pump exchange (pump exchange cohort), and in 58 patients, only anonymized survival data were collected (anonymized cohort, AC). Patients in the PIC contributed to the baseline demographics, survival, adverse events, quality of life (QoL) (EuroQoL-5 Dimensions-5 Levels visual analogue scale), and functional capacity (6 min walk distance) assessments, while patients in the AC contributed only to survival.

RESULTS

Primary implant cohort patients had a mean age of 56 years and were predominantly male (89%) with 48% ischaemic aetiology. The majority of subjects was designated bridge to transplant (66%) and had INTERMACS Profiles 1-3 (70%). At baseline, the subjects had poor functional capacity (104 ± 140 m) and impaired QoL (35 ± 19 points). The overall survival rate of the PIC was 63.3% and survival free of stroke was 58.1% at 5 years. Significant improvements in functional capacity and QoL were observed and maintained for 5 years (301 ± 131 m and 64 ± 20 points, respectively).

CONCLUSIONS

Real-world data from the ELEVATE registry demonstrate an overall survival rate for primary implants of 63.3%. In the PIC, reductions in adverse events for patients in the extended follow-up and improved QoL and functional capacity were observed at 5 years in this patient population with advanced heart failure.

Driveline infection according to driveline positioning in left ventricular assist device implant recipients

We conducted a prospective, open-labeled, clinical trial, with a two-by-two factorial design, of argon cold plasma application and two different types of driveline positioning for the prevention of driveline infection (DLI) in 80 patients with a left ventricular assist device (LVAD) implant. Here, we present the results of intracorporeal loop positioning (n = 40) versus no intracorporeal loop positioning (n = 40). Patients were followed up for 1 year. According to the Driveline Expert STagINg and carE grading (DESTINE) system, a DLI was considered in case of a stage 2 or higher graded infection. During follow-up, 29 (36%) patients experienced a DLI, 16 in the group with intracorporeal loop positioning and 13 in the group with no intracorporeal loop positioning. Kaplan-Meier estimates of freedom from DLI showed no statistically significant difference between study groups during follow-up (p = 0.33). In detail, 30-day freedom from DLI was for the groups with and without intracorporeal loop positioning 92 and 92%, respectively, and 1-year freedom from DLI was 51 and 62%, respectively. In conclusion, this controlled clinical trial was unable to show a statistically significant difference in freedom from DLI during one year of follow-up in groups with or without intracorporeal loop positioning. However, larger trials have to confirm these results.

Pulmonary Vascular Resistance to Predict Right Heart Failure in Patients Undergoing Left Ventricular Assist Device Implantation

Right heart failure (RHF) is associated with poor outcomes, especially in patients undergoing left ventricular assist device (LVAD) implantation. The aim of this study was to identify predictors of RHF after LVAD implantation. Of 129 consecutive patients (mean age 56 ± 11 years, 89% male) undergoing LVAD implantation, 34 developed RHF. Compared to patients without RHF, those with RHF required longer invasive mechanical ventilation and had longer intensive care unit and hospital stays (p < 0.01). One-year all-cause mortality was significantly higher in patients with versus without RHF after LVAD implantation (29.4% vs. 1.2%; hazard ratio 35.4; 95% confidence interval 4.5-277; p < 0.001). Mortality was highest in patients with delayed RHF after initial LVAD-only implantation (66.7%). Patients who did versus did not develop RHF had significantly higher baseline pulmonary vascular resistance (PVR; 404 ± 375 vs. 234 ± 162 dyn/s/cm5; p = 0.01). PVR > 250 dyn/s/cm5 was a significant predictor of survival in patients with RHF after LVAD implantation. These data confirm the negative impact of RHF on morbidity and mortality after LVAD implantation. Preoperative PVR > 250 dyn/s/cm5 determined using invasive right heart catheterization was an independent predictor of developing RHF after LVAD implantation, and of subsequent mortality, and could be used for risk stratification in the setting for deciding between single or biventricular support strategy.

Argon Cold Plasma Use and Driveline Infection in Left Ventricular Assist Device Implant Recipients

We conducted a prospective open-labeled, clinical trial, with a two-by-two factorial design, of argon cold plasma (ACP) application and two different types of driveline positioning for the prevention of driveline infection (DLI) in patients with a left ventricular assist device (LVAD) implant. Here, we present the results of ACP application versus no ACP application. Eighty patients were allocated to the control group (no preventive ACP use; n = 40) or ACP group (preventive ACP use for 30 days post-LVAD implantation; n = 40). Patients were followed up for 1 year. The secondary endpoint was survival on device. Preventive ACP use improved 30 day freedom from DLI significantly (100% vs. 85%; p = 0.012); results remained significant at 6 months (92% vs. 69%, p = 0.007) and were 55% and 60%, respectively ( p = 0.65) at 1 year follow-up. With respect to survival on device, results in the control and ACP groups did not differ significantly at 30 days (97.5% vs. 100%, respectively; p = 0.32), but tended to be lower in the control group than in the ACP group at 1 year follow-up (74% vs. 90%, respectively; p = 0.09). In conclusion, preventive ACP use was able to significantly reduce DLI both during the application period and up to 6 months after LVAD implantation.

Long-term assist device patients admitted to ICU: Tips and pitfalls

Left ventricular assist device (LVAD) therapy is well-established in the treatment of end-stage cardiac failure. Indications are bridge to transplant (BTT), bridge to candidacy (BTC), bridge to recovery (BTR), and destination therapy (DT). The durability and adverse event (AE) rate of LVADs have improved over the years. However, due to donor shortage, the duration of support in the BTT population has increased tremendously; similarly, DT patients are on the device for a long time. Consequently, the number of readmissions of long-term LVAD patients has increased. In cases of severe AEs, intensive care unit (ICU) treatment can be necessary. Infectious complications are the most common AE. Furthermore, embolic or hemorrhagic strokes can occur due to foreign surfaces, acquired von Willebrand syndrome, and anticoagulation treatment. Another consequence of the coagulative status, in combination with the continuous flow, are gastrointestinal bleeding events. Moreover, in most patients, an isolated LVAD is implanted, and this involves the risk of late right heart failure. Adjustment of pump speed and optimization of the volume status can help solve this issue. Malignant arrhythmias, pre-existing or de novo after LVAD implantation, can be a life-threatening AE. Antiarrhythmic medical therapy or ablation are potential treatment options. As for specific LVADs, the Medtronic HeartWare™ ventricular assist device (HVAD) is not manufactured and distributed currently; however, 4000 patients are still on the device. Pump thrombosis can occur, wherein thrombolytic therapy is the first-line treatment option. Additionally, the HVAD can fail to restart after controller exchange due to technical issues, and precautions must be taken. The Momentum 3 trial showed superior survival without pump exchange or disabling stroke in patients treated with the HeartMate 3^Ⓡ (HM3; Abbott, Abbott Park, IL, USA) device in comparison to the HeartMate II (HMII). However, in a few cases, a twisted graft or bio debris formation between the outflow graft and bend relief could be observed, causing outflow graft obstruction. Patients on LVADs are still heart failure patients, in many cases with comorbidities. Therefore, many situations can occur requiring ICU treatment. Ethical aspects should always be the focus when taking care of these patients.

Vitamin D deficiency and driveline infection in patients with a left ventricular assist device implant

Driveline infection is a frequent complication in recipients of durable left ventricular assist devices (LVAD), but its cause is largely unclear. Since vitamin D supplementation can reduce the risk of infections, we aimed at investigating the association of vitamin D deficiency with driveline infection. In 154 patients with continuous flow LVAD implants, we assessed 2-year risk of driveline infection according to vitamin D status (circulating 25-hydroxyvitamin D < 25 nmol/L or ⩾25 nmol/L). Of the study cohort, 34% (n = 53) had 25-hydroxyvitamin D concentrations <25 nmol/L. Kaplan-Meir estimates of 2-year freedom from driveline infection were in the vitamin D deficient and vitamin D non-deficient groups 49.7% and 74.2%, respectively (p = 0.017). Covariate-adjusted hazard ratio of driveline infection for the vitamin D deficient versus non-deficient group was 2.51 [95% CI: 1.11-5.69; p = 0.028). Circulating concentrations of endocrine regulators of calcium and phosphorus metabolism such as parathyroid hormone, 1,25-dihydroxyvitamin D, and fibroblast growth factor-23 were not significantly associated with the risk of driveline infection (p-values > 0.15). In total, our data indicate that in LVAD recipients deficient vitamin D status is a predictor of driveline infection, but future studies are needed to investigate whether these associations are causal.

Identifying patients at risk: multi-centre comparison of HeartMate 3 and HeartWare left ventricular assist devices

AIMS

Since the withdrawal of HeartWare (HVAD) from the global market, there is an ongoing discussion if and which patients require prophylactically exchange for a HeartMate 3 (HM3). Therefore, it is important to study outcome differences between HVAD and HM3 patients. Because centres differ in patient selection and standard of care, we performed a propensity score (PS)-based study including centres that implanted both devices and aimed to identify which HVAD patients are at highest risk.

METHODS AND RESULTS

We performed an international multi-centre study (n = 1021) including centres that implanted HVAD and HM3. PS-matching was performed using clinical variables and the implanting centre. Survival and complications were compared. As a sensitivity analysis, PS-adjusted Cox regression was performed. Landmark analysis with conditional survival >2 years was conducted to evaluate long-term survival differences. To identify which HVAD patients may benefit from a HM3 upgrade, Cox regression using pre-operative variables and their interaction with device type was performed. Survival was significantly better for HM3 patients (P < 0.01) in 458 matched patients, with a median follow-up of 23 months. Within the matched cohort, HM3 patients had a median age of 58 years, and 83% were male, 80% of the HVAD patients were male, with a median age of 59 years. PS-adjusted Cox regression confirmed a significantly better survival for HM3 patients when compared with HVAD, with a HR of 1.46 (95% confidence interval 1.14-1.85, P < 0.01). Pump thrombosis (P < 0.01) and ischaemic stroke (P < 0.01) occurred less in HM3 patients. No difference was found for haemorrhagic stroke, right heart failure, driveline infection, and major bleeding. Landmark-analysis confirmed a significant difference in conditional survival >2 years after implantation (P = 0.03). None of the pre-operative variable interactions in the Cox regression were significant.

CONCLUSIONS

HM3 patients have a significantly better survival and a lower incidence of ischaemic strokes and pump thrombosis than HVAD patients. This survival difference persisted after 2 years of implantation. Additional research using post-operative variables is warranted to identify which HVAD patients need an upgrade to HM3 or expedited transplantation.

The Role of Daily Implant-Based Multiparametric Telemonitoring in Patients with a Ventricular Assist Device

The telemonitoring of heart failure (HF) patients is becoming increasingly important. This study aimed to evaluate the benefit of telemonitoring in end-stage HF patients with a ventricular-assistance device (VAD). A total of 26 HF-patients (66 ± 11 years, 88% male) on VAD therapy with an implantable cardioverter-defibrillator (ICD) or a cardiac resynchronization defibrillator (CRT-D) including telemonitoring function were enrolled. The long-term follow-up data (4.10 ± 2.58 years) were assessed. All the patients (n = 26, 100%) received daily ICD/CRT-D telemonitoring. In most of the patients (73%, n = 19), the telemedical center had to take action for a mean of three times. An acute alert due to sustained ventricular arrhythmias (VAs) occurred in 12 patients (63%) with 50% of them (n = 6) requiring ICD shock delivery. Eight patients (67%) were hospitalized due to symptomatic VAs. In 11 patients (92%), immediate medication adjustments were recommended. Relevant lead issues were revealed in thirteen patients (50%), with six patients (46%) undergoing consecutive lead revisions. Most of the events (83%) were detected within 24 h. Daily telemonitoring significantly reduced the number of in-hospital device controls by 44% (p < 0.01). The telemonitoring ensured that cardiac arrhythmias and device/lead problems were identified early, allowing pre-emptive and prompt interventions. In addition, the telemonitoring significantly reduced the number of in-hospital device controls in this cohort of HF patients.

Noninvasive evaluation of the hemodynamic status in patients after heart transplantation or left ventricular assist device implantation

INTRODUCTION

Hemodynamic assessment is crucial after heart transplantation (HTX) or left ventricular assist device (LVAD) implantation. Gold-standard is invasive assessment via thermodilution (TD). Noninvasive pulse contour analysis (NPCA) is a new technology that is supposed to determine hemodynamics completely noninvasive. We aimed to validate this technology in HTX and LVAD patients and conducted a prospective single-center cohort study.

METHODS

Patients after HTX or LVAD implantation underwent right heart catheterization including TD. NPCA using the CNAP Monitor (V.5.2.14; CNSystems Medizintechnik AG, Graz, Austria) was performed simultaneously. Three TD measurements were compared with simultaneous NPCA measurements for hemodynamic assessment. To describe the agreement between TD and NPCA, Bland-Altman analysis was done.

RESULTS

In total, 28 patients were prospectively enrolled (HTX: n = 10, LVAD: n = 18). Bland-Altman analysis revealed a mean bias of +1.05 l/min (limits of agreement ± 4.09 l/min, percentage error 62.1%) for cardiac output (CO). In LVAD patients, no adequate NPCA signal could be obtained. In 5 patients (27.8%), any NPCA signal could be detected, but was considered as low signal quality.

CONCLUSION

In conclusion, according to our limited data in a small cohort of HTX and LVAD patients, NPCA using the CNAP Monitor seems not to be suitable for noninvasive evaluation of the hemodynamic status.

Pre-operative risk factors for driveline infection in left ventricular-assist device patients

AIMS

Implantation of left ventricular-assist devices (LVAD) to treat end-stage heart failure is of increasing relevance due to donor shortage. Infections of the driveline are common adverse events. LVAD infections can lead to high urgency listings for transplantation. However, transplantation in patients with infection leads to worse post-transplantation outcomes. This study aims to evaluate specific risk factors for driveline infections at the time of implantation.

METHODS AND RESULTS

Four hundred forty-one patients receiving either Heartmate II or Heartware system from August 2009 to October 2013 were assessed. An expert committee sorted patients into four different groups concerning the likeliness of infection. Twenty-eight (6%) of discussed infection cases were judged as secured, 33 (7%) as likely, 18 (4%) as possible, and 20 (4%) as unlikely. The remaining 342 (78%) subjects showed either no signs of infection at all times (329 [75%]) or developed signs of infection in a second observation period within 1 year after ending of the first observation period (13 [3%]). For a better discriminatory power, cases of secured and likely infections were tested against the group with no infection at all times in a Cox proportional hazard model. Among all variables tested by univariate analysis (significance level P < 0.15), only age (P = 0.07), LVAD-type (P = 0.12), need for another thoracic operation (P = 0.02), and serum creatinine value (P = 0.02) reached statistical significance. These were subsequently subjected to multivariate analysis to calculate the cumulative risk of developing a drive infection. The multivariate analysis showed that of all the potential risk factors tested, only the necessity of re-thoracotomy or secondary thoracic closure had a significant, protective effect (hazard ratio [95% CI] = 0.45 [0.21-0.95]; P = 0.04).

CONCLUSION

This single-centre cohort study shows that driveline infections are common adverse events. The duration of support represents the major risk factor for LVAD driveline infections.

Use of the CytoSorb® filter for elimination of residual therapeutic argatroban concentrations during heparinized cardiopulmonary bypass for heart transplantation

INTRODUCTION

No antidote or established extracorporeal elimination strategy is available for argatroban. Hemadsorption facilitates elimination of smaller drugs.

CASE REPORT

A 34-year-old patient underwent urgent heart transplantation. Because of a history of heparin-induced thrombocytopenia, preoperative anticoagulation was performed with argatroban. Despite ceasing of the continuous infusion of argatroban 2 h before surgery, concentration only declined from 0.60 μg/ml to 0.58 μg/ml before surgery, and the activated clotting time (ACT) value shortly was 223 s. Microvascular bleeding had been observed when starting surgery. A CytoSorb® absorption column was integrated into the system of the heparin-anticoagulated cardiopulmonary bypass (CPB) circuit and a flow of 400 mL/min provided during the 2 h of extracorporeal circulation. The argatroban concentration after weaning from CPB was 0.04 μg/ml and satisfying hemostasis had been achieved after protamine administration.

CONCLUSION

Data indicate that the CytoSorb® absorption column might be an effective tool for quick extracorporeal removal of therapeutic concentrations of argatroban.

Bacteriophage-Enriched Galenic for Intrapericardial Ventricular Assist Device Infection

We report a case of severe outflow graft infection following left ventricular assist device (LVAD) implantation. A 51-year old male LVAD patient was readmitted to our hospital presenting signs of systemic infection. One year previously, LVAD implantation (HeartMate3, Abbott, Chicago, IL, USA) with concomitant patent foramen ovale closure had been performed in the context of end-stage heart failure due to dilative cardiomyopathy (INTERMACS III). The indication for LVAD-therapy was bridge-to-candidacy, since the patient did not instantly fulfill all criteria for cardiac transplantation. At admission, a PET-CT scan unveiled fluid accumulation, encircling the outflow-graft prosthesis (SUVmax 10.5) with contrast-enhancement involving the intrathoracic driveline (SUVmax 11.2). Since cardiac transplantation was not feasible, the patient underwent surgical revision. In the first step, redo sternotomy was performed with local debridement, including jet lavage. Intraoperative swabs confirmed bacterial infection with staphylococcus aureus. Following this, the patient underwent negative pressure wound therapy (NPWT) with instillation using the V.A.C. VERAFLO system (KCI-3M, San Antonio, TX, USA) for a total of 19 days. Due to the severity of infection, local bacteriophage application was performed within the wound closure. In order to concentrate phage therapy at the infection site, phages were applied using a novel semi-fluid galenic. After wound closure, the patient was discharged with an uneventful course. A control PET-CT scan 3 months after discharge showed a significant decrease in infection (outflow graft: SUVmax 7.2, intrathoracic driveline: SUVmax 3.0) correlated with contrast enhancement. Bacterial infection of intrathoracic VAD components represents a severe and potentially life-threatening complication. If cardiac transplantation is not feasible, complex wound management strategies are required. Local bacteriophage therapy might be a promising addition to already established therapeutical options. In order to improve bacteriophage retention at the wound site, application of a viscous galenic might be beneficial.

The HeartWare Ventricular Assist Device (HVAD): A Single Institutional 10-Year Experience

OBJECTIVES

 The aim of this study was to analyze our 10-year experience with the HVAD in a real-world scenario in a high-volume German heart center.

METHODS

 We retrospectively analyzed outcomes of adults (≥18 years) with terminal heart failure (HF), who underwent HVAD implantation for durable LVAD therapy in our center between October 2009 and March 2020. Primary and secondary end points were all-cause death after implantation and LVAD-associated complications, respectively. We focused the distinct analyses on risk profiles at the time of implantation and implant strategies, i.e., bridge-to-transplant (BTT) or destination therapy (DT).

RESULTS

 A total of 510 patients were included, with 229 and 281 individuals in Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level 1 (45%) and 2 to 4, respectively. Median follow-up was 26 months (IQR: 5-54 months). Overall survival at 1, 3, and 5 years after HVAD implantation was 66% (95% CI; 61.7-70%), 49.4% (95% CI; 44.9-53.8%), and 37.4% (95% CI; 32.8-42%), not censored for LVAD exchange, LVAD explantation, or heart transplantation. INTERMACS level 1 and peri-operative temporary right heart assistance were independent risk factors for survival. Survival was best in BTT patients undergoing heart transplantation at any time during follow-up. The INTERMACS level at time of HVAD implantation did not affect survival after heart transplantation. Freedom from the combined end point of any device-associated severe complication and death was 44.5% (95% CI; 40-48.8%) at 1-year after implantation.

CONCLUSION

 The HVAD is a reliable pump for durable mechanical circulatory support even in high-risk patients. Still, heart transplantation outperforms durable MCS therapy for a superior long-term survival.

Left ventricular unloading during extracorporeal life support for myocardial infarction with cardiogenic shock: surgical venting versus Impella device

OBJECTIVES

Patients in cardiogenic shock supported with venoarterial extracorporeal membrane oxygenation (VA-ECMO) may experience severe complications from reduced left ventricular (LV) unloading and increased cardiac afterload. These effects are usually modified by adding a percutaneous direct Impella vent or surgical LV vent on top of VA-ECMO in selected patients. However, direct comparisons between 2 LV unloading strategies in patients with cardiogenic shock due to myocardial infarction are lacking. Therefore, we sought to investigate the impact of these 2 different approaches.

METHODS

We enrolled 112 patients treated with an Impella or surgical LV vent during VA-ECMO support between January 2014 and February 2020. The primary endpoint was 30-day mortality. Secondary endpoints included rates of myocardial recovery or transition to durable mechanical circulatory support. Additionally, we assessed adverse events such as peripheral ischaemic complications requiring intervention, sepsis and ischaemic stroke.

RESULTS

At 30 days, 38 patients in the Impella group (54%) and 26 patients in the surgical LV vent group (63%) had died (relative risk with Impella 0.78, 95% confidence interval 0.47-1.30; P = 0.35). Impella group and the surgical LV vent group differed significantly with respect to the secondary end points including rates of myocardial recovery (24% and 7%, respectively; P = 0.022) and rates of durable mechanical circulatory support (17% and 42%, P = 0.012). Complication rates were not statistically different between the 2 groups.

CONCLUSIONS

The use of Impella device as therapeutic unloading therapy during VA-ECMO did not significantly reduce 30-day mortality compared to surgical LV vent in patients with cardiogenic shock due to acute myocardial infarction.

Donor-recipient risk assessment tools in heart transplant recipients: the Bad Oeynhausen experience

AIMS

Some risk assessment tools have been developed to categorize mortality risk in heart transplant recipients, but it is unclear whether these tools can be used interchangeable in different transplant regions.

METHODS AND RESULTS

We performed a retrospective single-centre study in 1049 adult German heart transplant recipients under jurisdiction of Eurotransplant. Univariable and multivariable Cox regression analysis was used to generate a risk scoring system. C-statistics were used to compare our score with a US score and a French score regarding their ability to discriminate between 1 year survivors and non-survivors within our study cohort. Of 38 parameters assessed, seven recipient-specific parameters [age, height, dilated cardiomyopathy (DCM), ischaemic cardiomyopathy (ICM), total bilirubin, extracorporeal membrane oxygenation (ECMO), and biventricular assist device/total artificial heart (BVAD/TAH) implant], one donor-specific parameter (cold ischaemic time), and one recipient-independent and donor-independent other parameter (late transplant era) were statistically significant in predicting 1 year mortality. The initial score was generated by using the regression coefficients from the multivariable analysis as follows: 1.70 * ln age - 4.0 * ln height - 0.9 * diagnosis (= 1 if diagnosis = DCM) - 0.67 * diagnosis (= 1 if diagnosis = ICM) + 0.33 * ln total bilirubin + 1.74 * ln cold ischaemic time + 0.98 * mechanical circulatory support (MCS) implant (= 1 if MCS implant = ECMO) + 0.47 * MCS implant (= 1 of MCS implant = BVAD/TAH) - 0.66 * transplant era (= 1 if transplant era = 2017-2018). The initial score was converted into the Bad Oeynhausen (BO) score as a positive integer variable by means of the following formula: BO score = (initial score + 8) * 3. In patients scoring 2 to <7 points (n = 112), 7 to <11 points (n = 580), 11 to <15 points (n = 339), and 15 to 20 points (n = 18), 1 year survival was 93.1%, 84.2%, 66.9%, and 27.8%, respectively. The c-index of our score was 0.73 [95% confidence interval (CI): 0.69-0.77]. Values were in our cohort for the US and French scores 0.66 (95% CI: 0.62-0.70) and 0.63 (95% CI: 0.59-0.67), respectively.

CONCLUSIONS

Data indicate that our score, but also risk assessment tools from other transplant regions, may be used as a reliable support for risk-adjusted organ allocation and potentially help to improve outcomes in heart transplantation. Further developments will have to include as yet unaccounted risk factors for even more reliable predictions.

Risk-adjusted analysis of long-term outcomes after on- versus off-pump coronary artery bypass grafting

OBJECTIVES

Recent data suggested that off-pump coronary artery bypass (OPCAB) may carry a higher risk for mortality in the long term when compared to on-pump coronary artery bypass (ONCAB). We, therefore, compared long-term survival and morbidity in patients undergoing ONCAB versus OPCAB in a large single-centre cohort.

METHODS

A total of 8981 patients undergoing isolated elective/urgent coronary artery bypass grafting between January 2009 and December 2019 were analysed. Patients were stratified into 2 groups (OPCAB n = 6649/ONCAB n = 2332). The primary end point was all-cause mortality. Secondary endpoints included repeat revascularization, stroke and myocardial infarction. To adjust for potential selection bias, 1:1 nearest neighbour propensity score (PS) matching was performed resulting in 1857 matched pairs. Moreover, sensitivity analysis was applied in the entire study cohort using multivariable- and PS-adjusted Cox regression analysis.

RESULTS

In the PS-matched cohort, 10-year mortality was similar between study groups [OPCAB 36.4% vs ONCAB 35.8%: hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.87-1.12; P = 0.84]. While 10-year outcomes of secondary endpoints did not differ significantly, risk of stroke (OPCAB 1.50% vs ONCAB 2.8%: HR 0.51, 95% CI 0.32-0.83; P = 0.006) and mortality (OPCAB 3.1% vs ONCAB 4.8%: HR 0.65, 95% CI 0.47-0.91; P = 0.011) at 1 year was lower in the OPCAB group. In the multivariable- and the PS-adjusted model, mortality at 10 years was not significantly different (OPCAB 34.1% vs ONCAB 35.7%: HR 0.97, 95% CI 0.87-1.08; P = 0.59 and HR 1.01, 95% CI 0.90-1.13; P = 0.91, respectively).

CONCLUSIONS

Data do not provide evidence that elective/urgent OPCAB is associated with significantly higher risks of mortality, repeat revascularization, or myocardial infarction during late follow-up when compared to ONCAB. Patients undergoing OPCAB may benefit from reduced risks of stroke and mortality within the first year postoperatively.

Clinical implications of late-onset right ventricular failure after implantation of a continuous-flow left ventricular assist device as bridge to transplantation

OBJECTIVES

The development of late-onset right ventricular failure (LoRVF) that occurs months after a continuous-flow left ventricular assist device (LVAD) is implanted is a clinical problem that warrants investigation. Our goal was to study the incidence, clinical manifestations and prognosis of LoRVF in a population of patients who received an LVAD as bridge to transplantation.

METHODS

Data were analysed from 97 consecutive patients who received an LVAD as bridge to transplantation and underwent a right heart catheterization at least 3 months after receiving an LVAD implantation. LoRVF was defined if both haemodynamic criteria of a central venous pressure >16 mmHg and a cardiac index <2.3 l/min/m2 were present. Clinical and echocardiographic variables, hospitalizations for heart failure and survival were compared between patients with and without LoRVF.

RESULTS

LoRVF was diagnosed in 13% of patients after a median time of 11 months. Patients with LoRVF presented preoperative worse right ventricular (RV) dilatation and severe tricuspid regurgitation. LORVF was also associated with postoperative RV dilatation, moderate to severe tricuspid regurgitation and lower tricuspid annular plane systolic excursion. LoRVF resulted in increased brain natriuretic peptide levels and the need for diuretics, lower haemoglobin levels and a higher rate of atrial fibrillation and gastrointestinal bleeding. The rate of hospitalizations for heart failure in patients with LoRVF was 46%, and 15% required an urgent transplantation due to refractory RV failure. LoRVF decreased global survival and survival free from hospitalizations for heart failure (P < 0.0001).

CONCLUSIONS

LoRVF after the implantation of an LVAD as bridge to transplantation is associated with higher morbidity and lower survival. The results suggest that the routine use of a right heart catheterization and transthoracic echocardiography may contribute to an early diagnosis before further severe complications due to refractory RV failure might occur.

ID NUMBER OF THE IRB APPROVAL

AZ-2019-521 on 10 July 2019.

Five-year outcomes of patients supported with HeartMate 3: a single-centre experience

OBJECTIVES

The HeartMate 3 left ventricular assist device was first implanted in 2014 and received the Conformité Européenne mark in 2015. Since then, several trials demonstrated its high haemocompatibility associated with good survival and low adverse events rates. Herein, we report our institutional experience with patients supported with HeartMate 3 for 5 years.

METHODS

This prospective cohort study included patients receiving a HeartMate 3 implantation in 2014 as part of the HeartMate 3 Conformité Européenne Mark clinical trial. Patients had follow-up visits every 3 months while on left ventricular assist device support, and all patients completed the 5-year follow-up. The primary end point was survival at 5 years. Secondary end points included adverse events, health status and quality of life.

RESULTS

Eight patients (men: 75%) aged 59 years (min-max: 52-66 years) were enrolled. At 5 years, survival was 100%. Patients remained on support for a median time of 1825 days (min-max: 101-1825 days); 2 patients successfully received cardiac transplants. No right heart failure, haemolysis, pump thrombosis, pump malfunction or neurological events occurred in any patients. A driveline infection was observed in 6 patients (0.25 events/patient-year). Compared to baseline, a significant improvement in quality of life and in New York Heart Association functional class was noted after the implant and for the whole follow-up time. A slight decline in kidney function and in the 6-min walk test results occurred after 3 years.

CONCLUSIONS

This study reports the longest single-centre follow-up of the HeartMate 3, showing excellent haemocompatibility over time with high survival and low complication rates at 5 years.

Cardiac recovery following left ventricular assist device therapy: experience of complete device explantation including ventricular patch plasty

OBJECTIVES

Myocardial recovery is a rare phenomenon in left ventricular assist device (LVAD) therapy. Surgical LVAD removal is associated with the risk of cardiac failure, and the individual evaluation of sufficient myocardial recovery is crucial. Thus, complete device explantation is not consistently performed to minimize perioperative risk. However, the remaining ventricular assist device components bear significant risks of infection or thrombosis. Therefore, we developed this study to evaluate a complete LVAD explantation protocol.

METHODS

All patients in our institution who had an LVAD explanted were enrolled in the study. Explant surgery involved removal of the driveline, pump housing, sewing ring and outflow graft. The ventricular wall was reconstructed by double patch plasty. Our analysis focused on surgical and postoperative outcome parameters, including all-cause mortality and major adverse cardiac and cerebrovascular events.

RESULTS

A total of 12 patients (HVAD, n = 5; HeartMate II, n = 3; HeartMate 3, n = 4) had myocardial recovery and qualified for our LVAD explantation study protocol [median age: 40 years, interquartile range (IQR) 33-52 years; 50% men]. Primary heart failure aetiology: myocarditis (n = 5), dilated cardiomyopathy (n = 4), toxic cardiomyopathy (n = 2) and valvular heart failure (n = 1). The median average duration on LVAD was 10 months (25-75%: IQR 8.5-30 months). The median left ventricular ejection fraction was 15% (IQR 13-18%) at LVAD implantation and 50% (IQR 45-50%) before LVAD explantation (P = 0.0025).The 30-day survival was 100%. The 1-year survival was 91.7%. All patients were discharged after a median 13 days (IQR 10-18 days) postoperatively. No patient had major adverse cardiac and cerebrovascular events. The New York Heart Association functional class remained consistent during the follow-up period (median New York Heart Association functional class: II, IQR II-II class) including preservation of ventricular function.

CONCLUSIONS

Complete LVAD explantation with ventricular patch plasty is feasible and has consistent long-term results.

Two-year outcome after implantation of a full magnetically levitated left ventricular assist device: results from the ELEVATE Registry

AIMS

The ELEVATE Registry was designed to study long-term outcomes with the Heartmate 3 (HM3), a fully magnetically levitated centrifugal ventricular assist device, in a real-world population following CE-mark approval.

METHODS AND RESULTS

A total of 540 patients, implanted in Europe and the Middle East were followed in ELEVATE. The registry included 463 patients receiving the HM3 as primary implant (Primary Implant Cohort), 19 patients underwent a pump upgrade from another device (Pump Exchange Cohort) and 58 patients who had experienced an outcome before having the possibility to sign the Informed Consent, for which only outcome data were collected (Anonymized Cohort). Data collection included demographics, survival, adverse events, EQ-5D Visual Analog Score quality of life (EQ-5D VAS QOL) questionnaire, and 6-min walk distance (6MWD). Mean age was 55.6 ± 11.7 years (89% male, 48% ischaemic cardiomyopathy). Seventy per cent of patients were in INTERMACS Profile 1-3 and 12.7% were on temporary mechanical circulatory support. Primary Implant Cohort survival was 83% after 2 years. In the Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation Primary Implant Cohort, strokes were observed in 10.2%, gastrointestinal bleedings in 9.7%, pump thrombosis in 1.5%, and outflow graft twists in 3.5%. Heartmate 3 implantation resulted in a significant and sustained improvement of functional capacity and QOL.

CONCLUSION

In a real-world population, cohort implanted with the HM3 left ventricular assist device we demonstrate good long-term survival, sustained improvement of functional capacity, and low rates of adverse events (including pump thrombosis).

CLINICALTRIALS.GOV IDENTIFIER

NCT02497950.

Exercise capacity in patients implanted with left ventricular assist devices for end-stage heart failure treatment

Funding Acknowledgements

Type of funding sources: None.

Introduction

Left ventricular assist device (LVAD) is an expanding therapy in end-stage heart failure today. Although LVAD therapy bears the potential to normalize cardiac output, a majority of patients show a severely impaired physical condition at the time of LVAD implantation. To date, no validated standardized training protocol is available, and established practices to effectively improve LVAD patients’ exercise tolerance is lacking. This study sought to investigate exercise capacity quantified by cardiopulmonary exercise testing (CPX) and a standardized six-minute walk test (6MWT) in patients after LVAD implantation.

Methods

We enrolled 30 end-stage heart failure patients who had received an LVAD implantation 20.7 ± 7.6 days prior to examination, mean age 54.9 ± 7.8 years, 26 males (87 %). Exercise tolerance was assessed using cardiopulmonary exercise testing (CPX) for maximal and submaximal exercise capacity, followed by a standardized (6MWT).

Results

Patients showed peak oxygen uptake values of 8.3 ± 2.4 ml/min/kg at a mean workload of 46.7 ± 11.3 watts and a mean anaerobic threshold of 6.7 ± 1.7 ml/min/kg at a workload of 32.6 ± 6.9 watts. Mean standardized 6-minute walking distance was at 183.8 ± 71.4 meters. There were no adverse events during exercise testing.

Conclusions

Cardiopulmonary exercise testing (CPX) and standardized 6MWT show severely impaired cardiopulmonary exercise capacity in patients after LVAD implantation, warranting further studies for dedicated training protocols, specifically focusing on LVAD patients to improve exercise tolerance at an acceptable safety profile.

Impact of extra-corporeal life support (ECLS) cannulation strategy on outcome after durable mechanical circulation support system implantation on behalf of durable MCS after ECLS Study Group

Background

The literature on outcomes of patients requiring durable mechanical circulatory support (MCS) after extra-corporeal life support (ECLS) is limited. The aim of this study was to investigate the impact of preoperative ECLS cannulation on postoperative outcome after durable MCS implantation.

Methods

The durable MCS after ECLS registry is a multicenter retrospective study that gathered data on consecutive patients who underwent durable MCS implantation after ECLS between January 2010 and August 2018 in eleven high volume European centers. Patients who underwent the implantation of total artificial heart, pulsatile pumps, or first-generation pumps after ECLS were excluded from the analysis. The remaining patients were divided into two groups; central ECLS group (cECLS) and peripheral ECLS group (pECLS). A 1:1 propensity score analysis was performed to identify two matched groups. The outcome of these two groups was compared.

Results

A total of 531 durable MCS after ECLS were implanted during this period. The ECLS cannulation site was peripheral in 87% (n=462) and central in 13% (n=69) of the patients. After excluding pulsatile pumps and total artificial heart patients, a total of 494 patients remained (pECLS =434 patients, cECLS =60 patients). A 1:1 propensity score analysis resulted in 2 matched groups (each 55 patients) with median age of 54 years (48-60 years) in cECLS group and 54 years (43-60 years) in pECLS group. HeartWare HVAD (Medtronic, Minneapolis, MN) was implanted in the majority of the patients (cECLS =71% vs. pECLS =76%, P=0.67). All postoperative morbidities were comparable between the groups. The thirty-day, one year and long-term survival was comparable between the groups (P=0.73).

Conclusions

The cannulation strategy of ECLS appears to have no impact on the post-operative outcome after durable MCS implantation.

Transition From Temporary to Durable Circulatory Support Systems

BACKGROUND

The decision to implant durable mechanical circulatory systems (MCSs) in patients on extracorporeal life support (ECLS) is challenging due to expected poor outcomes in these patients.

OBJECTIVES

The aim of this study was to identify outcome predictors that may facilitate future patient selection and decision making.

METHODS

The Durable MCS after ECLS registry is a multicenter retrospective study that gathered data on consecutive patients who underwent MCS implantation after ECLS between January 2010 and August 2018 in 11 high-volume European centers. Several perioperative parameters were collected. The primary endpoint was survival at 1 year after durable MCS implantation.

RESULTS

A total of 531 durable MCSs after ECLS were implanted during this period. The average patient age was 53 ± 12 years old. ECLS cannulation was peripheral in 87% of patients and 33% of the patients had history of cardiopulmonary resuscitation before ECLS implantation. The 30-day, 1-year, and 3-year actuarial survival rates were 77%, 53%, and 43%, respectively. The following predictors for 1-year outcome have been observed: age, female sex, lactate value, Model of End-Stage Liver Disease XI score, history of atrial fibrillation, redo surgery, and body mass index >30 kg/m². On the basis of this data, a risk score and an app to estimate 1-year mortality was created.

CONCLUSIONS

The outcome in patients receiving durable MCS after ECLS remains limited, yet preoperative factors may allow differentiating futile patients from those with significant survival benefit.

Secondary aortic valve replacement in continuous flow left ventricular assist device therapy

The purpose of the study was to investigate the outcome of secondary surgical aortic valve replacement (sSAVR) in patients with severe aortic regurgitation (AR) in the context of ventricular assist device (VAD) therapy. From 2009 to 2020, 792 patients underwent cf-LVAD implantation [HVAD (Medtronic, USA), n = 585, and HM 3 (Abbott, USA), n = 207]. All cf-LVAD patients with severe AR requiring secondary AVR were enrolled in this study. A total of six patients (median, 40 years, IQR; 34-61 years, 50% male) underwent secondary surgical aortic valve replacement (sSAVR) after cf-LVAD implantation. Median time of previous LVAD support was 26 months (IQR: 21-29 months). Two patients required additional tricuspid valve repair (TVR) and one patient underwent SAVR after failed TAVR. Four patients needed temporary right ventricular assist device (RVAD) with a median of 30 days (IQR; 29-33 days). Three patients were bridged to urgent heart transplantation due to persevering right heart failure, whereas two destination therapy (DT) candidates survived without any associated complications. An additional DT patient died of pneumonia 1 month after sSAVR. Secondary surgical aortic valve replacement in ongoing LVAD patients is an advanced procedure for a complex cohort. In our series, sSAVR was safely performed and effective, but involved a high-risk for subsequent right heart failure, requiring urgent heart transplantation. In LVAD patients with severe AR requiring treatment where TAVR is not feasible, sSAVR can be evaluated as salvage option for bridge to transplant patients or selected destination therapy candidates.

Impact of a surgical approach for implantation of durable left ventricular assist devices in patients on extracorporeal life support

BACKGROUND

The aim of this study was to evaluate the impact of the surgical approach on the postoperative outcome in patients who underwent left ventricular assist device (LVAD) implantation after having received veno-arterial extracorporeal life support (va-ECLS) using data from a European registry (ECLS-VAD). Five hundred and thirty-one patients were included.

METHODS

A propensity score-adjusted outcome analysis was performed, resulting in 324 patients in the full sternotomy (FS) group and 39 in the less invasive surgery (LIS) group.

RESULTS

The surgery lasted in median 236 min in the FS group versus 263 min in the LIS group (p = 0.289). The median chest tube output during the first 24 h was similar in both groups. Patients who underwent implantation with an FS required more blood products during the first 24 postoperative hours (median 16 vs. 12, p = 0.033). The incidence of revision due to bleeding was also higher (35.5 vs. 15.4%, p = 0.016). A temporary postoperative right ventricular assist device was necessary in 45.1 (FS) versus 23.1% (LIS) of patients, respectively (p = 0.067). No stroke occurred in the LIS group during the first 30 days after surgery (7.4% in the FS group). The incidence of stroke and of renal, hepatic, and respiratory failure during the follow-up was similar in both groups. The 30-day and one-year survival were similar in both groups.

CONCLUSION

LIS for implantation of a durable LVAD in patients on va-ECLS implanted for cardiogenic shock is associated with less revision due to bleeding, less administration of blood products and absence of perioperative stroke, with no impact on survival.

Complications of left ventricular assist devices causing high urgency status on waiting list: impact on outcome after heart transplantation

Aims

Heart transplantation (HTx) represents optimal care for advanced heart failure. Left ventricular assist devices (LVADs) are often needed as a bridge‐to‐transplant (BTT) therapy to support patients during the wait for a donor organ. Prolonged support increases the risk for LVAD complications that may affect the outcome after HTx.

Methods and results

A total of 342 patients undergoing HTx after LVAD as BTT in a 10‐year period in two German high‐volume HTx centres were retrospectively analysed. While 73 patients were transplanted without LVAD complications and with regular waiting list status (T, n = 73), the remaining 269 patients were transplanted with high urgency status (HU) and further divided with regard to the observed leading LVAD complications (infection: HU1, n = 91; thrombosis: HU2, n = 32; stroke: HU3, n = 38; right heart failure: HU4, n = 41; arrhythmia: HU5, n = 23; bleeding: HU6, n = 18; device malfunction: HU7, n = 26). Postoperative hospitalization was prolonged in patients with LVAD complications. Analyses of perioperative morbidity revealed no differences regarding primary graft dysfunction, renal failure, and neurological events except postoperative infections. Short‐term survival, as well as Kaplan–Meier survival analysis, indicated comparable results between the different study groups without disadvantages for patients with LVAD complications.

Conclusions

Left ventricular assist device therapy can impair the outcome after HTx. However, the occurrence of LVAD complications may not impact on outcome after HTx. Thus, we cannot support the prioritization or discrimination of HTx candidates according to distinct mechanical circulatory support‐associated complications. Future allocation strategies have to respect that device‐related complications may define urgency but do not impact on the outcome after HTx.

Identification of characteristics, risk factors, and predictors of recurrent LVAD thrombosis: conditions in HeartWare devices

Background

Redictors of repetitive left-ventricular assist device (LVAD)-thrombosis have not been studied yet.

Methods

We identified predictors of recurrent LVAD thrombosis in HeartWare (HVAD) patients in a long-term study from 2010 until 2020. We included all patients with two or more thrombolysis treatments for repetitive HVAD thrombosis and effectiveness of thrombolytic therapy was defined as freedom from stroke, death, another HVAD thrombosis, or surgical device exchange within 30 days after the event. Study endpoints also include all-cause mortality and heart transplantation.

Results

A total of 534 HVAD implantations have been screened, and 73 patients (13.7%) developed first HVAD thrombosis after a median of 10 months (IQR; 6–21 months). 46 of these patients had effective thrombolysis in 71.7% (n = 33/46). After a median of 14 months (IQR 4–32 months) follow-up, 17 patients (51.5%) had developed a second HVAD thrombosis and all were treated with t-PA therapy again, resulting in effectiveness in 76.5% (n = 13/17). The four patients with ineffective t-PA therapy underwent subsequent surgical HVAD exchange. Multiple Cox regression model analysis revealed time interval between HVAD implantation and first thrombosis as an independent risk factor of recurrent thrombosis (HR, 0.93, 95% CI 0.87–0.99, p = 0.031). Kaplan–Meier analysis at 3 year follow-up showed no significant difference in overall survival for recurrent vs non-recurrent thrombosis groups (log-rank test, p = 0.959).

Conclusion

Recurrent HVAD thrombosis mostly appears within 12 months after first thrombosis. Systemic t-PA therapy for recurrent pump thrombosis seems safe, achieving comparable effectiveness rates to initial t-PA therapy. Survival does not differ between patients with or without recurrent HVAD thrombosis.

Patients with ventricular assist device and cerebral entrapment-Supporting skullcap reimplantation

Effects of cranioplasty (CP) and skullcap reimplantation after decompressive craniectomy (DC) for cerebral hemorrhage or malignant brain infarction in patients with left ventricular assist device (LVAD) support as bridge to transplantation has not been surveyed yet. The aim of this study was to evaluate outcome and management after CP when aiming for transplantation. Data were collected from our prospective institutional database including all patients undergoing LVAD implantation between 2010 and 2019. Six patients needed CP procedures and were included. Our analysis focused on postoperative outcome, survival, and facilitation of heart transplantation. Study endpoints included also all-cause mortality. From a total of 1010 LVAD implantations during analysis period in our center, six bridge-to-transplantation LVAD patients [median age at LVAD implantation: 32.5 years (IQR: 24.8-39.5 years); four male, HVAD, n = 3; HM II, n = 1; HM 3, n = 2] underwent CP with imminent entrapment secondary to cerebral hemorrhage or malignant infarction. Primary heart failure etiology was myocarditis (n = 2), dilated (n = 2), or ischemic (n = 2). Median INTERMACS class was 1.5 (IQR; 1.0-2.8). Median time on LVAD support to DC procedure was 33 months (IQR: 16-48 months). The indication for DC was intraparenchymal hemorrhage (n = 4), subdural hematoma (n = 1), and malignant middle cerebral artery infarction (n = 1). After a median time of 4 months (IQR: 3.3-4.0 months, range; 2.0-10 months) post DC procedure, CP was subsequently performed without profound neurologic disabilities in all patients. After median time of 26 months (IQR: 21-42 months) follow-up, three patients successfully received heart transplantation, one patient could undergo LVAD explantation for myocardial recovery, and the remaining two patients are still on the list awaiting heart transplantation. CP procedure with skullcap reimplantation is feasible and can be safely performed in LVAD patients, which subsequently may even be eligible for heart transplantation with beneficial prognosis.

Mechanical circulatory support as a bridge to candidacy in adults with transposition of the great arteries and a systemic right ventricle

OBJECTIVES

Clinical experience with continuous flow ventricular assist devices (VADs) in patients with transposition of the great arteries (TGA) including dextro-TGA and congenitally corrected TGA is rare, and indications as well as potential benefits or specific hurdles remain unclear. Therefore, our goal was to report on our experience regarding VAD therapy in adult patients with TGA as a bridge to candidacy.

METHODS

We performed a single-centre retrospective study of all adult patients with TGA with systemic right ventricular failure who had continuous flow VAD implants between 2010 and 2018. Study end points were all causes of death, major cardiac and cerebrovascular adverse events or pump thrombosis. Follow-up continued until the time of the heart transplant.

RESULTS

A total of 6 patients (4 men) had a continuous flow VAD implanted in the context of a failing systemic right ventricle (dextro-TGA after the Mustard procedure: n = 3; congenitally corrected TGA: n = 3). Demographics: mean age 32 ± 5.7 years; median Interagency Registry for Mechanically Assisted Circulatory Support: level II (range 1-4), mean pulmonary artery 48 ± 13 mmHg, mean pulmonary vascular resistance 5.6 ± 3.5 Wood units. Postoperative data: intensive care unit stay: 16 ± 9.7 days; in-hospital survival: 100%; no early VAD-related complications occurred. Mean follow-up: 33 ± 18 months; persistent left-side paresis: n = 1; minor (non-disabling) stroke: n = 2. Post-VAD pulmonary artery: 19 ± 3.4 mmHg; P < 0.005; post-VAD pulmonary resistance: 2.2 ± 0.55 Wood units; P = 0.066. Four patients had heart transplants after a mean waiting time of 30 months after the VAD was implanted; 2 patients are still on the waiting list (waiting time: 52 and 24 months).

CONCLUSIONS

Continuous flow VAD therapy is a feasible therapeutic option in adult patients with TGA and a failing systemic right ventricle as a bridge to candidacy and a bridge to a heart transplant.

Mechanical circulatory support does not reduce advanced myocardial fibrosis in patients with end-stage heart failure

AIMS

Mechanical unloading by ventricular assist devices (VADs) has become increasingly important for the therapy of end-stage heart failure during the last decade. However, VAD support was claimed to be associated with partial reverse remodelling. Unfortunately, the literature describes the contradictory effects of VAD systems on cardiac fibrosis, a hallmark of cardiac remodelling. To clarify these inconsistent results, the effects on cardiac fibrosis before and after mechanical unloading in 125 patients were examined.

METHODS AND RESULTS

Left ventricular myocardial tissue from ischaemic or non-ischaemic cardiomyopathy patients undergoing VAD implantation and subsequent cardiac transplantation and non-failing hearts of the control group were analysed for 4-hydroxyproline (4OH-P) content as a marker for collagen protein. In addition, collagen cross-linking and mRNAs of collagens I and III and transforming growth factor beta-1 were measured. 4OH-P content was significantly increased in failing hearts compared with the control group and increased (P < 0.05) after mechanical unloading (nmol/mg tissue, mean ± standard deviation: 16.74 ± 9.68 vs. 7.75 ± 2.39 and 18.57 ± 9.19). However, plotting of the 4OH-P ratios (post/pre-VAD) against the collagen content pre-VAD could be fitted by non-linear regression. Collagen cross-linking correlated strongly with the total collagen content in pre- and post-VAD myocardium (r²  = 0.73 and 0.71, respectively). In contrast to the total collagen content, all three mRNAs of fibrotic genes were significantly down-regulated during VAD support when compared to pre-VAD.

CONCLUSIONS

This investigation of a comparably large patient cohort revealed that cardiac fibrosis was strongly increased in heart failure and increased even after mechanical unloading. The mRNAs of collagens I and III are independently regulated from the collagen protein.

Renal Function in Patients with or without a Left Ventricular Assist Device Implant During Listing for a Heart Transplant

Background

Left ventricular assist device (LVAD) implantation may improve kidney function, but in patients awaiting heart transplantation, the long-term effects of LVAD implantation on renal function and subsequent clinical outcome are unclear.

Material/Methods

We analyzed data in patients with LVAD implants (n=139) and without LVAD implants (n=1038) who were listed for a heart transplant at our institution between 2000 and 2019. The primary endpoint was an impairment in renal function (decrease of creatinine-based estimated glomerular filtration rate [eGFR] by ≥30%) up to a maximum of 2 years after listing. Secondary endpoints were chronic kidney disease stage 4 or 5, heart transplantation, survival during listing, and 1-year survival after transplantation.

Results

Values for eGFR increased after LVAD implantation (P=0.001) and were higher at the time of waitlisting in the LVAD group than in the non-LVAD group (P=0.002), but were similar between groups at the end of waitlisting (P=0.75). Two-year freedom from renal impairment was 50.6% and 66.7% in the LVAD and non-LVAD groups, respectively, with a multivariable-adjusted hazard ratio for the LVAD versus the non-LVAD group of 1.78 (95% confidence interval 1.19–2.68; P=0.005). Two-year freedom from chronic kidney disease stages 4–5 was similar between study groups (LVAD group: 83.5%; non-LVAD group: 80.1%; =0.50). The 2-year probability of transplantation was slightly lower in the LVAD group than in the non-LVAD group (50.0% and 55.8%, respectively, P=0.017). However, 2-year survival on the waiting list and 1-year survival after transplantation did not differ significantly between study groups (P-values >0.20).

Conclusions

Our data indicate a transient improvement in creatinine-based eGFR values by LVAD implantation without influencing survival.

Cardiomyopathy-associated mutations in the RS domain affect nuclear localization of RBM20

Mutations in RBM20 encoding the RNA-binding motif protein 20 (RBM20) are associated with an early onset and clinically severe forms of cardiomyopathies. Transcriptome analyses revealed RBM20 as an important regulator of cardiac alternative splicing. RBM20 mutations are especially localized in exons 9 and 11 including the highly conserved arginine and serine-rich domain (RS domain). Here, we investigated in several cardiomyopathy patients, the previously described RBM20-mutation p.Pro638Leu localized within the RS domain. In addition, we identified in a patient the novel mutation p.Val914Ala localized in the (glutamate-rich) Glu-rich domain of RBM20 encoded by exon 11. Its impact on the disease was investigated with a novel TTN- and RYR2-splicing assay based on the patients' cardiac messenger RNA. Furthermore, we showed in cell culture and in human cardiac tissue that mutant RBM20-p.Pro638Leu is not localized in the nuclei but causes an abnormal cytoplasmic localization of the protein. In contrast the splicing deficient RBM20-p.Val914Ala has no influence on the intracellular localization. These results indicate that disease-associated variants in RBM20 lead to aberrant splicing through different pathomechanisms dependent on the localization of the mutation. This might have an impact on the future development of therapeutic strategies for the treatment of RBM20-induced cardiomyopathies.

Current perspectives on mechanical circulatory support

Mechanical circulatory support gained a significant value in the armamentarium of heart failure therapy because of the increased awareness of the prevalence of heart failure and the tremendous advances in the field of mechanical circulatory support during the last decades. Current device technologies already complement a heart transplant as the gold standard of treatment for patients with end-stage heart failure refractory to conservative medical therapy. This article reviews important aspects of mechanical circulatory support therapy and focuses on currently debated issues.