Propensity score-based analysis of long-term follow-up in patients supported with durable centrifugal left ventricular assist devices: the EUROMACS analysis

Temporal Analysis in Outcomes of Long-Term Mechanical Circulatory Support: Retrospective Study

BACKGROUND

 Mechanical assist device indications have changed in recent years. Reduced incidence of complications, better survival, and the third generation of mechanical support devices contributed to this change. In this single-center study, we focused on two time periods that are characterized by the use of different types of mechanical support devices, different patient characteristics, and change in the indications.

METHODS

 The data were processed from the European Registry for Patients with Mechanical Circulatory Support (EUROMACS). We retrospectively defined two time intervals to reflect changes in ventricular assist device technology (period 1: 2007-2015; period 2: 2016-20222). A total of 181 patients underwent left ventricular assist device implantation. Device utilization was the following: HeartMate II = 52 (76.4%) and HeartWare = 16 (23.6%) in period 1 and HeartMate II = 2 (1.8%), HeartMate 3 = 70 (61:9%), HeartWare = 29 (25.7%), SynCardia TAH = 10 (8.8%), and BerlinHeart EXCOR = 2 (1.8%) in period 2. The outcomes of the time intervals were analyzed and evaluated.

RESULTS

 Survival was significantly higher during the second time period. Multivariate analysis revealed that age and bypass pump time are independent predictors of mortality. Idiopathic cardiomyopathy, bypass time, and the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) score are independent predictors of adverse events. Furthermore, the first period was noted to be at an increased risk of the following adverse events: pump thrombosis, gastrointestinal bleeding, and bleeding events.

CONCLUSION

 Despite the higher risk profile of the patients and persistent challenges, during the second period, there was a significant decrease in mortality and morbidity. The use of the HeartMate 3 device may have contributed to this result.

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.

Surgical Outcomes of Centrifugal Continuous-Flow Implantable Left Ventricular Assist Devices: Heartmate 3 versus Heartware Ventricular Assist Device

Background

Left ventricular assist devices (LVADs) are widely employed as a therapeutic option for end-stage heart failure. We evaluated the outcomes associated with centrifugal-flow LVAD implantation, comparing 2 device models: the Heartmate 3 (HM3) and the Heartware Ventricular Assist Device (HVAD).

Methods

Data were collected from patients who underwent LVAD implantation between June 1, 2015 and December 31, 2022. We analyzed overall survival, first rehospitalization, and early, late, and LVAD-related complications.

Results

In total, 74 patients underwent LVAD implantation, with 42 receiving the HM3 and 32 the HVAD. A mild Interagency Registry for Mechanically Assisted Circulatory Support score was more common among HM3 than HVAD recipients (p=0.006), and patients receiving the HM3 exhibited lower rates of preoperative ventilator use (p=0.010) and extracorporeal membrane oxygenation (p=0.039). The overall early mortality rate was 5.4% (4 of 74 patients), with no significant difference between groups. Regarding early right ventricular (RV) failure, HM3 implantation was associated with a lower rate (13 of 42 [31.0%]) than HVAD implantation (18 of 32 [56.2%], p=0.051). The median rehospitalization-free period was longer for HM3 recipients (16.9 months) than HVAD recipients (5.3 months, p=0.013). Furthermore, HM3 recipients displayed a lower incidence of late hemorrhagic stroke (p=0.016). In the multivariable analysis, preoperative use of continuous renal replacement therapy (odds ratio, 22.31; p=0.002) was the only significant predictor of postoperative RV failure.

Conclusion

The LVAD models (HM3 and HVAD) demonstrated comparable overall survival rates. However, the HM3 was associated with a lower risk of late hemorrhagic stroke.

Soluble Suppression of Tumorigenicity-2 Predicts Mortality and Right Heart Failure in Patients With a Left Ventricular Assist Device

BACKGROUND

Soluble suppression of tumorigenicity-2 (sST2) predicts mortality in patients with heart failure. The predictive value of sST2 in patients with a left ventricular assist device remains unknown. Therefore, we studied the relationship between sST2 and outcome after left ventricular assist device implantation.

METHODS AND RESULTS

sST2 levels of patients with a left ventricular assist device implanted between January 2015 and December 2022 were included in this observational study. The median follow-up was 25 months, during which 1573 postoperative sST2 levels were measured in 199 patients, with a median of 29 ng/mL. Survival of patients with normal and elevated preoperative levels was compared using Kaplan-Meier analysis, which did not differ significantly (P=0.22) between both groups. The relationship between postoperative sST2, survival, and right heart failure was evaluated using a joint model, which showed a significant relationship between the absolute sST2 level and mortality, with a hazard ratio (HR) of 1.20 (95% CI, 1.10-1.130; P<0.01) and an HR of 1.22 (95% CI, 1.07-1.39; P=0.01) for right heart failure, both per 10-unit sST2 increase. The sST2 instantaneous change was not predictive for survival or right heart failure (P=0.99 and P=0.94, respectively). Multivariate joint model analysis showed a significant relationship between sST2 with mortality adjusted for NT-proBNP (N-terminal pro-B-type natriuretic peptide), with an HR of 1.19 (95% CI, 1.00-1.42; P=0.05), whereas the HR of right heart failure was not significant (1.22 [95% CI, 0.94-1.59]; P=0.14), both per 10-unit sST2 increase.

CONCLUSIONS

Time-dependent postoperative sST2 predicts all-cause mortality after left ventricular assist device implantation after adjustment for NT-proBNP. Future research is warranted into possible target interventions and the optimal monitoring frequency.

Efficacy and Complication Profiles of Left Ventricular Assist Devices in Adult Heart Failure Management: A Systematic Review and Meta-Analysis

Left ventricular assist devices (LVADs) have marked a milestone in the evolution of treatment for patients with end-stage heart failure. Their popularity and use are steadily rising. This systematic review and meta-analysis aimed to evaluate the effectiveness of LVADs in improving the survival rate of patients with end-stage heart failure and to identify the complications or adverse events associated with LVAD use. Articles for this systematic review and meta-analysis were sourced from PubMed, Google Scholar, and the Cochrane Library databases. Only studies that met the predefined PICOS eligibility criteria were analyzed. LVADs significantly improved the 6, 12, 18, and 24-month survival rates in patients with end-stage heart failure compared to no LVAD or other therapies: OR 1.87 (95%CI [1.27-2.76]), OR 2.29 (95%CI [1.61-3.26]), OR 2.07 (95%CI [0.61-6.61]), and OR 1.73 (95%CI [0.88-3.41]) for 6, 12, 18, and 24 months, respectively. The incidence of adverse events was significantly higher in the LVAD group than in the non-LVAD treatments: bleeding OR 12.53 (95%CI [2.60-60.41]), infections OR 4.15 (95%CI [1.19-14.45]), stroke OR 2.58 (95%CI [1.38-4.82]), and arrhythmia OR 2.81 (95%CI [1.64-4.80]). Overall, complications were higher in the LVAD group compared to those without LVAD treatment. Hospital readmissions due to adverse events were significantly more frequent in the LVAD group, OR 2.98 (95%CI [1.38-6.43]). Despite the elevated risk of adverse events associated with LVADs, these devices have demonstrated a notable enhancement in the survival outcomes for patients with end-stage heart failure.

When all Else Fails, Try This: The HeartMate III Left Ventricle Assist Device

Heart failure (HF) is a progressive disease. It is estimated that more than 250,000 patients suffer from advanced HF with reduced ejection fraction refractory to medical therapy. With limited donor pool for heart transplant, continue flow left ventricle assist device (LVAD) is a lifesaving treatment option for patients with advanced HF. This review will provide an update on indications, contraindications, and associated adverse events for LVAD support with a summary of the current outcomes data.

Five-Year Outcome After Continuous Flow LVAD With Full-Magnetic (HeartMate 3) Versus Hybrid Levitation System (HeartWare): A Propensity-Score Matched Study From an All-Comers Multicentre Registry

Despite the withdrawal of the HeartWare Ventricular Assist Device (HVAD), hundreds of patients are still supported with this continuous-flow pump, and the long-term management of these patients is still under debate. This study aims to analyse 5 years survival and freedom from major adverse events in patients supported by HVAD and HeartMate3 (HM3). From 2010 to 2022, the MIRAMACS Italian Registry enrolled all-comer patients receiving a LVAD support at seven Cardiac Surgery Centres. Out of 447 LVAD implantation, 214 (47.9%) received HM3 and 233 (52.1%) received HVAD. Cox-regression analysis adjusted for major confounders showed an increased risk for mortality (HR 1.5 [1.2-1.9]; p = 0.031), for both ischemic stroke (HR 2.08 [1.06-4.08]; p = 0.033) and haemorrhagic stroke (HR 2.6 [1.3-4.9]; p = 0.005), and for pump thrombosis (HR 25.7 [3.5-188.9]; p < 0.001) in HVAD patients. The propensity-score matching analysis (130 pairs of HVAD vs. HM3) confirmed a significantly lower 5 years survival (81.25% vs. 64.1%; p 0.02), freedom from haemorrhagic stroke (90.5% vs. 70.1%; p < 0.001) and from pump thrombosis (98.5% vs. 74.7%; p < 0.001) in HVAD cohort. Although similar perioperative outcome, patients implanted with HVAD developed a higher risk for mortality, haemorrhagic stroke and thrombosis during 5 years of follow-up compared to HM3 patients.

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.

Impact of preoperative mitral regurgitation on left ventricular assist device patients: propensity score-matched analysis of the EUROMACS dataset

OBJECTIVES

Mitral regurgitation (MR) is frequently observed in patients undergoing left ventricular assist device implantation. We investigated the impact of preoperative MR on left ventricular assist device patients.

METHODS

A retrospective propensity score-matched analysis of adult patients enrolled in the EUROMACS registry between 1 January 2011 and 30 November 2021 was performed. Patients were divided into 2 groups according to the grade of preoperative MR: none-to-mild (MR 0-II) or moderate-to-severe (MR III-IV).

RESULTS

Following 1:1 propensity score matching, each group consisted of 914 patients. Incidence of postoperative temporary right ventricular support, reoperation for bleeding and dialysis was similar. MR III-IV demonstrated shorter median intensive care unit stay [14 days (6; 27.8) vs 10 days (5; 22), P = 0.004] and ventilation time [72 h (22, 320) vs 31 h (18, 150), P < 0.001]. Mortality was lower for MR III-IV patients [subdistribution hazard ratio: 0.66, 95% confidence interval (CI): 0.59-0.73, P < 0.001]. The 1-year survival was 68.1% (95% CI: 65.1-71.3%) in MR 0-II and 75% (95% CI: 72.1-78%) in MR III-IV. A lower incidence of total complications [odds ratio (OR): 0.93 (0.89-0.98), P = 0.003] and trend towards a lower risk of neurological dysfunction (subdistribution hazard ratio: 0.79; 95% CI: 0.61-1.01, P = 0.063) and sustained ventricular tachycardia [OR: 0.93 (0.54-1.03), P = 0.074] were demonstrated for MR III-IV. The risk of fatal stroke and pump thrombosis was similar.

CONCLUSIONS

Moderate-to-severe MR in patients undergoing left ventricular assist device implantation is associated with better mid-term survival and lower incidence of total major adverse events and complications. The incidence of severe postoperative complications including fatal stroke and device thrombosis was similar.

Bridging to transplant with HeartMate 3 left ventricular assist devices in the new heart organ allocation system: An individualized approach

BACKGROUND

Following the MOMENTUM 3 trial and the discontinuation of the HeartWare HVAD, the HeartMate 3 LVAD (HM 3) has become the main durable device for bridging to transplantation; however, outcome of this strategy in the new heart allocation system is not well understood.

METHODS

The United Network for Organ Sharing (UNOS) registry was queried to include adult patients (≥18 years old) listed for heart transplantation between 2010 and 2020. Trends in durable LVAD utilization and outcomes of patients with HM 3 LVAD were examined in the pre- vs post-heart allocation system.

RESULTS

From 2017 to 2020, there was a 28.3% decline in the number of patients waitlisted with an FDA-approved durable LVAD. Overall, 449 patients were waitlisted with HM 3 in the pre-allocation era compared to 1094 patients in the post-allocation. Cumulative incidence of heart transplantation (53.4% vs 50.7%, p = 0.76) and death or delisting for worsening status (5.0%, vs 4.2%, p = 0.43) at 1-year after listing with HM 3 LVAD was comparable in the pre- vs post-allocation era. Old age (>50), ischemic HF, poor functional status, elevated creatinine (>1.3 mg/dL), pulmonary hypertension (>3 WU), and obesity (body mass index > 33 kg/m²) were predictors of post-transplant graft mortality after bridging with HM 3.

CONCLUSIONS

While the utilization of durable devices as BTT have declined under the new heart allocation system, bridging with HM 3 LVAD remains a safe strategy in carefully selected patients. Bridging decision should be individualized based on patient risk factors.

Ventricular Assist Devices: Challenges of the One-device Era

Heart failure (HF) is linked to to high mortality rates and recurrent hospitalisations despite medical and device-based achievements. The use of left ventricular assist devices (LVADs) has improved survival among patients with advanced HF. Significant progress has been achieved with the new generation of continuous-flow devices, particularly with the fully magnetically levitated HeartMate 3. In June 2021, Medtronic announced the abrupt withdrawal of the HeartWare device from the market. This decision has introduced a new era in which the field of mechanical support for advanced HF patients is dominated by a single device - the HeartMate 3. The direct clinical and economic consequences of this change will necessitate new surgical considerations. Because of the expected need for HeartWare device replacement in small patients, new surgical techniques and device adaptation will be needed. The new single-device era will hopefully encourage scientists and engineers to create innovations in the advanced HF arena. Special considerations should be taken during the COVID-19 pandemic when treating patients with LVADs.

Third-generation continuous-flow left ventricular assist devices: a comparative outcome analysis by device type

AIMS

Continuous-flow left ventricular assist devices (CF-LVADs) have become a standard of care in end-stage heart failure. Limited data exist comparing outcomes of HeartMate3 (HM3) and HeartWare HVAD (HW). We aimed to compare midterm outcomes of these devices.

METHODS AND RESULTS

Investigator-initiated retrospective-observational comparative analysis of all patients who underwent primary LVAD implantation of either HM3 or HW at our centre between January 2010 and December 2020. Data were derived from a prospective registry. Primary endpoints were all-cause mortality and heart transplantation. Secondary endpoints included device-related major adverse cardiac and cerebrovascular events, which included major bleeding, major neurological dysfunction (defined as persisting neurological impairment for ≥24 h), device-related major infection (excluding driveline infections), major device malfunctions leading to re-intervention or partial device exchange (pump failure, outflow-graft twist or failure, controller failure, battery failure, patient cable failure, but excluding pump thrombosis), and pump thrombosis. Further secondary endpoints included right heart failure, gastrointestinal bleeding, driveline infections, and surgical re-interventions. The secondary outcomes were analysed not only for the first event but also for recurrent events. The analysis included competing risks analysis and recurrent event regression analysis, with adjustment for confounders age, gender, body mass index (BMI), and Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level. Out of 106 primary CF-LVAD implantations, 36 (34%) received HM3 and 70 (66%) received HW. Median follow-up was 1.48 years [interquartile range 0.67, 2.41]. HM3 was more often implanted in men (91.7% vs. 72.9%, P = 0.024); patients were older (median 61 years [54, 66.5] vs. 52.5 years [43, 60], P < 0.001), had a higher BMI (median 26.7 kg/m² [23.4, 29.0] vs. 24.3 kg/m² [20.7, 27.4], P = 0.013), had more comorbidities, and were more likely targeted for destination therapy (36.1% vs. 14.3%, P = 0.010). Death occurred in 33.3% of HM3 patients, compared with 22.9% of HW patients, P = 0.247 (probability of survival at 4 years, 54.7% vs. 74.1%, P = 0.296). After adjustment for confounders, we observed a significant six-fold risk increase in device malfunctions for HW [hazard ratio (HR) 6.49, 95% confidence interval (CI) [1.89, 22.32], P = 0.003], but no significant differences in pump thrombosis (P = 0.173) or overall survival (P = 0.801).

CONCLUSIONS

Comparing midterm outcomes between HM3 and HW for LVAD support from a prospective registry, HW patients had a significantly higher risk of device malfunctions. No significant differences were evident between devices in overall survival and in respect to most outcomes.

HVAD to HeartMate 3 Left Ventricular Assist Device Exchange: Best Practices Recommendations

The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices.

Validation of Intrinsic Left Ventricular Assist Device Data Tracking Algorithm for Early Recognition of Centrifugal Flow Pump Thrombosis

Advanced stage heart failure patients can benefit from the unloading effects of an implantable left ventricular assist device. Despite best clinical practice, LVADs are associated with adverse events, such as pump thrombosis (PT). An adaptive algorithm alerting when an individual’s appropriate levels in pump power uptake are exceeded, such as in the case of PT, can improve therapy of patients implanted with a centrifugal LVAD. We retrospectively studied 75 patients implanted with a centrifugal LVAD in a single center. A previously optimized adaptive pump power-tracking algorithm was compared to clinical best practice and clinically available constant threshold algorithms. Algorithm performances were analyzed in a PT group (n = 16 patients with 30 PT events) and a thoroughly selected control group (n = 59 patients, 34.7 patient years of LVAD data). Comparison of the adaptive power-tracking algorithm with the best performing constant threshold algorithm resulted in sensitivity of 83.3% vs. 86.7% and specificity of 98.9% vs. 95.3%, respectively. The power-tracking algorithm produced one false positive detection every 11.6 patient years and early warnings with a median of 3.6 days prior to PT diagnosis. In conclusion, a retrospective single-center validation study with real-world patient data demonstrated advantageous application of a power-tracking algorithm into LVAD systems and clinical practice.

Trends and Outcomes of Left Ventricular Assist Device Therapy: JACC Focus Seminar

As the prevalence of advanced heart failure continues to rise, treatment strategies for select patients include heart transplantation or durable left ventricular assist device (LVAD) support, both of which improve quality of life and extend survival. Recently, the HeartMate 3 has been incorporated into clinical practice, the United Network for Organ Sharing donor heart allocation system was revised, and the management of LVAD-related complications has evolved. Contemporary LVAD recipients have greater preoperative illness severity, but survival is higher and adverse event rates are lower compared with prior eras. This is driven by advances in device design, patient selection, surgical techniques, and long-term management. However, bleeding, infection, neurologic events, and right ventricular failure continue to limit broader implementation of LVAD support. Ongoing efforts to optimize management of patients implanted with current devices and parallel development of next-generation devices are likely to further improve outcomes for patients with advanced heart failure.

When Nothing Goes Right: Risk Factors and Biomarkers of Right Heart Failure after Left Ventricular Assist Device Implantation

Right heart failure (RHF) is a severe complication after left ventricular assist device (LVAD) implantation. The aim of this study was to analyze the incidence, risk factors, and biomarkers for late RHF including the possible superiority of the device and implantation method. This retrospective, single-center study included patients who underwent LVAD implantation between 2014 and 2018. Primary outcome was freedom from RHF over one-year after LVAD implantation; secondary outcomes included pre- and postoperative risk factors and biomarkers for RHF. Of the 145 consecutive patients (HeartMate 3/HVAD: n = 70/75; female: 13.8%), thirty-one patients (21.4%) suffered RHF after a mean LVAD support of median (IQR) 105 (118) days. LVAD implantation method (less invasive: 46.7% vs. 35.1%, p = 0.29) did not differ significantly in patients with or without RHF, whereas the incidence of RHF was lower in HeartMate 3 vs. HVAD patients (12.9% vs. 29.3%, p = 0.016). Multivariate Cox proportional hazard analysis identified HVAD (HR 4.61, 95% CI 1.12–18.98; p = 0.03), early post-op heart rate (HR 0.96, 95% CI 0.93–0.99; p = 0.02), and central venous pressure (CVP) (HR 1.21, 95% CI 1.05–1.39; p = 0.01) as independent risk factors for RHF, but no association of RHF with increased all-cause mortality (HR 1.00, 95% CI 0.99–1.01; p = 0.50) was found. To conclude, HVAD use, lower heart rate, and higher CVP early post-op were independent risk factors for RHF following LVAD implantation.

HVAD to HeartMate 3 left ventricular assist device exchange: Best practices recommendations

The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices.

Comparative analysis of LVAD patients in regard of ischaemic or idiopathic cardiomyopathy: A propensity-score analysis of EUROMACS data

BACKGROUND

Despite recent advances in management of patients with advanced heart failure, mortality remains high. Aim of this study was to compare impact of different aetiology of ischaemic and idiopathic cardiomyopathy on early outcomes and long-term survival of patients after left ventricular assist device implantation.

METHODS

European Registry for Patients with Mechanical Circulatory Support (EUROMACS) gathers clinical data and follow-up parameters of LVAD recipients. Patients enrolled in the EUROMACS registry with primary diagnosis of either ischaemic (n = 1190) or idiopathic (n = 812) cardiomyopathy were included. Primary Endpoints were early mortality as well as long-term survival. Secondary endpoint were major postoperative adverse events, such as need for rethoracotomy. Additionally, a propensity-score matching analysis was performed for patients with ischaemic (n = 509) and idiopathic (n = 509) cardiomyopathy.

RESULTS

In terms of basic demographics and baseline parameters the two groups significantly differed as expected before propensity-score matching due to different aetiology of cardiomyopathy. Seven-day (52 (4.4%) versus 18 (2.2%); p = 0.009), 30-day (153 (12.9%) versus 73 (9.0%); p = 0.008) and in-hospital mortality (253 (19.7%) versus 123 (15.1%); p = 0.009) were significantly lower in the idiopathic cardiomyopathy group compared to the ischaemic cardiomyopathy group, whereas after propensity-score matching 30-day (p = 0.169) was comparable and in-hospital mortality (p = 0.051) was almost significant. Kaplan-Meier survival analysis revealed no significant difference in regard of long-term survival after propensity-score matching (Breslow-test p = 0.161 and LogRank-test p = 0.113).

CONCLUSION

Though patients with ischaemic and idiopathic cardiomyopathy suffer from different cardiomyopathy aetiologies, 30-day-mortality and long-term survival of both groups were similar leading to the conclusion that covariates predominately influence mortality and survival of ischaemic and idiopathic cardiomyopathies.

Physiology of Continuous-Flow Left Ventricular Assist Device Therapy

The expanding use of continuous-flow left ventricular assist devices (CF-LVADs) for end-stage heart failure warrants familiarity with the physiologic interaction of the device with the native circulation. Contemporary devices utilize predominantly centrifugal flow and, to a lesser extent, axial flow rotors that vary with respect to their intrinsic flow characteristics. Flow can be manipulated with adjustments to preload and afterload as in the native heart, and ascertainment of the predicted effects is provided by differential pressure-flow (H-Q) curves or loops. Valvular heart disease, especially aortic regurgitation, may significantly affect adequacy of mechanical support. In contrast, atrioventricular and ventriculoventricular timing is of less certain significance. Although beneficial effects of device therapy are typically seen due to enhanced distal perfusion, unloading of the left ventricle and atrium, and amelioration of secondary pulmonary hypertension, negative effects of CF-LVAD therapy on right ventricular filling and function, through right-sided loading and septal interaction, can make optimization challenging. Additionally, a lack of pulsatile energy provided by CF-LVAD therapy has physiologic consequences for end-organ function and may be responsible for a series of adverse effects. Rheological effects of intravascular pumps, especially shear stress exposure, result in platelet activation and hemolysis, which may result in both thrombotic and hemorrhagic consequences. Development of novel solutions for untoward device-circulatory interactions will facilitate hemodynamic support while mitigating adverse events. © 2021 American Physiological Society. Compr Physiol 12:1-37, 2021.

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.