Long-term Left Ventricular Assist Device Support Research Articles

Percutaneous Stenting of a Stenotic Berlin Heart Outflow Cannula Graft in a 2 Year Old Child.

Left ventricular assist device (LVAD) outflow obstruction is a rare complication of long-term LVAD support. We present the first case of successful percutaneous stent implantation in a pediatric patient with LVAD outflow obstruction.

Mechanical circulatory support for adults in Japan: A 10-year perspective.

Globalization in Asia and consequent strengthening of healthcare economic factors in tandem with an increasing heart failure (HF) population have enhanced potential for development and progress in the fields of HF medicine and mechanical circulatory support (MCS). In Japan, there are unique opportunities to investigate the outcome of acute and chronic MCS and a national registry for percutaneous and implantable left ventricular assist device (LVAD) including Impella pumps has been established. A Peripheral extracorporeal membrane oxygenation (ECMO) for acute MCS has been used in more than 7000 patients annually and Impella usage in more than 4000 patients over the past 4 years was noted. Recently, a novel centrifugal pump with hydrodynamically levitated impeller was developed and approved for mid-term extracorporeal circulatory support. In terms of chronic MCS more than 1200 continuous flow LVADs have been implanted during the past decade, and 2-year survival rate after primary LVAD implantation is 91%. Because of donor organ shortage, more than 70% of heart transplant recipients required LVAD support for more than 3 years and prevention and treatment of complications during long-term LVAD support have become important. Five important topics including hemocompatibility-related complications, LVAD infections, aortic valve insufficiency, right ventricular failure and cardiac recovery during LVAD support are discussed in this review for improving clinical outcomes. Findings from Japan will continue to provide useful information regarding MCS for the Asia-Pacific region and beyond.

Mechanical Device Malfunction of the HeartMate II Versus the HeartMate 3 Left Ventricular Assist Device: The Rotterdam Experience.

Mechanical device malfunction remains a known issue in left ventricular assist devices (LVADs). We investigated the incidence of mechanical device malfunction in the HeartMate II and HeartMate 3 LVADs. We conducted a retrospective study of all HeartMate II and HeartMate 3 LVADs implanted in our center. We evaluated major malfunction, potential major malfunction, minor malfunction, and need of device exchange. In total, 163 patients received an LVAD; in 63 (39%) a HeartMate II, and in 100 (61%) a HeartMate 3, median support time of respectively 24.6 months (interquartile range [IQR]: 32.4) and 21.1 months [IQR: 27.2]. Mechanical device malfunction, consisting of both major and potential major malfunction, occurred significantly less in the HeartMate 3 patients with a hazard ratio (HR) of 0.37 (95% Confidence Interval [CI]: 0.15-0.87, p = 0.022). Major malfunction alone occurred significantly less in HeartMate 3 patients with a HR of 0.18 (95% CI: 0.05-0.66, p = 0.009). HeartMate 3 patients had a significantly decreased hazard of a pump or outflow graft exchange (HR 0.13, 95% CI: 0.08-0.81, p = 0.008). System controller defects occurred significantly less in HM 3 patients (p = 0.007), but battery-clips defects occurred significantly more in HM 3 patients (p = 0.039). Major device malfunction including pump or outflow graft exchange occurred significantly less in HeartMate 3 compared to HeartMate II, while minor malfunctions were similar. Periodical assessment of the technical integrity of the device remains necessary during long-term LVAD support.

Interventional Procedures for Left Ventricular Assist Device-Associated Complications.

As patients on long-term left ventricular assist device (LVAD) face a substantial risk for open cardiac reoperation, interventional treatment approaches are becoming increasingly important in this population. We evaluated data of 871 patients who were on LVAD support between January 1, 2016 and December 1, 2020. Interventional treatments for LVAD-associated complications were performed in 76 patients. Seventeen patients underwent transcatheter aortic valve replacements (TAVR) and 61 patients underwent outflow graft interventions (OGI). TAVR improved symptoms in patients with severe symptomatic aortic regurgitation. Postinterventional complications included aggravation of preexisting right heart failure (RHF), third-degree atrioventricular block, and intrapump thrombosis (in 3 [16.7%], 2 [11.1%], and 1 [5.6%] patients, respectively). In outflow graft obstructions, OGI led to recovery of LVAD flow ( p < 0.001), unloading of the left ventricle ( p = 0.004), decrease of aortic valve opening time ( p = 0.010), and improvement of right heart function ( p < 0.001). Complications included bleeding, RHF, and others (in 9 [10.8%], 5 [6.0%], and 5 [6.0%] patients, respectively). Eight (9.6%) patients died within the hospital stay after OGI, including mortality secondary to prolonged cardiogenic shock. In conclusion, interventional procedures are a feasible and safe treatment modality for LVAD-associated complications.

Risk factors of gynecological bleeding in female patients with left-ventricular assist device.

Women with implantable left-ventricular assist devices (LVADs) experience gynecological bleeding (GYN-bleeding). However, a few studies have investigated female-specific problems. Therefore, this study aimed to identify the risk factors for adverse GYN-bleeding after LVAD implantation. We retrospectively analyzed 59 women (mean age: 41 ± 15years) with long-term implantable LVAD support (≥ 6months) at our institution between 2005 and 2018. The history of GYN-bleeding before implantation was defined as abnormal utero-ovarian bleeding, excessive menstruation, uterine fibroids, and endometrial lesions. GYN-bleeding after implantation was defined as a requirement of emergency outpatient visits and/or hospitalization, blood transfusions, hormonal therapy, and/or surgery. Additionally, risk factors for GYN-bleeding were identified using the Cox regression model. Twenty-four GYN-bleeding cases were seen in 15 patients (two times: five patients, three times: two patients, 0.18 events per patient-year). The 1- and 2-year GYN-bleeding-free rates were 84% and 73%, respectively. Twelve patients (17 events) required RBC ≥ 4 units, and five patients (7 events) required FFP ≥ 4 units. Seven patients required pseudomenopausal treatment after blood transfusion, and four patients required surgical treatment. Fifteen patients with GYN-bleeding after implantation were significantly younger than the remaining 44 patients without GYN-bleeding (34 ± 12years vs. 43 ± 16years, P = 0.02). Multivariable risk analysis showed a history of GYN-bleeding before implantation was a significant risk factor (hazard ratio 3.7 [1.2-10.6], P = 0.004). Patients with a history of GYN-bleeding before LVAD implantation have a high risk of developing GYN-bleeding after implantation. We should identify the high-risk population and prepare for the management of GYN-bleeding.

The effect of long-term left ventricular assist device support on flow-sensitive plasma microRNA levels

BackgroundImplantation of current generation left ventricular assist devices (LVADs) in the treatment of end-stage heart failure (HF), not only improves HF symptoms and end-organ perfusion, but also leads to cellular and molecular responses, presumably in response to the continuous flow generated by these devices. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression in multiple biological processes, including the pathogenesis of HF. In our study, we examined the influence of long-term LVAD support on changes in flow-sensitive miRNAs in plasma. Materials and methodsBlood samples from patients with end-stage heart failure (N = 33; age = 55.7 ± 11.6 years) were collected before LVAD implantation and 3, 6, 9, and 12 months after implantation. Plasma levels of the flow-sensitive miRNAs; miR-10a, miR-10b, miR-146a, miR-146b, miR-663a, miR-663b, miR-21, miR-155, and miR-126 were measured using quantitative PCR. ResultsIncreasing quantities of miR-126 (P < 0.03) and miR-146a (P < 0.02) was observed at each follow-up visit after LVAD implantation. A positive association between miR-155 and Belcaro score (P < 0.04) and an inverse correlation between miR-126 and endothelial function, measured as the reactive hyperemia index (P < 0.05), was observed. ConclusionsOur observations suggest that after LVAD implantation, low pulsatile flow up-regulates plasma levels of circulating flow-sensitive miRNAs, contributing to endothelial dysfunction and vascular remodeling.

Impact of Type of Left Ventricular Assist Device (LVAD) on Health-Related Quality of Life during Prolonged LVAD Support

Purpose Left ventricular assist devices (LVADs) have emerged as an important treatment option for bridging patients with heart failure to transplant. LVADs have shown improved survival; however, the impact of LVAD type on the quality of life (QoL) while on long-term LVAD support is unknown. We aimed to evaluate the QoL of patients while supported with a LVAD in Japan. Methods 299 patients enrolled in the Japanese Registry for Mechanically Assisted Circulatory Support (J-MACS), who were listed for transplant or likely to be listed, received a LVAD from 2010 to 2018 and had full QoL data, were enrolled. QoL data, such as visual analogue scale (VAS) and EQ-5D-3L by 5 dimensions (5D: mobility, self-care, usual activities, pain/discomfort and anxiety/depression) before and at 3- and 12-months after implantation of a LVAD were obtained from the J-MACS Registry. These patients were divided into 3 groups; primary implantable LVAD (iLVAD) (N=263), primary paracorporeal LVAD (pLVAD) (N=9) and bridge from paracorporeal to implantable LVAD (BTB) (N=27). Results VAS in all groups significantly increased from before to 3- and 12-months after LVAD implantation(p Conclusion QoL as VAS and 5D were significantly improved after implantation of any LVAD type. However, VAS and 5D except anxiety/depression in patients with pLVAD were significantly lower and more problems than those in patients with iLVAD. These differences were eliminated by converting from pLVAD to iLVAD. BTB might be a beneficial treatment option to improve QoL as well as patient's survival.

Aortic Insufficiency Causes Symptomatic Heart Failure during Left Ventricular Assist Device Support.

De novo aortic insufficiency is often documented during long-term left ventricular assist device (LVAD) support, despite the absence of aortic insufficiency at the time of LVAD implantation. However, whether aortic insufficiency affects long-term mortality and symptomatic heart failure in LVAD-supported patients remains controversial. We aimed to examine whether aortic insufficiency development influenced mortality and symptomatic heart failure following LVAD implantation. Fifty-three patients who underwent durable LVAD implantation between January 1, 2008 and April 31, 2017 were retrospectively examined in a single center institute. After discharge, we performed the echocardiographic examination in accordance with the Japanese registry for the mechanically assisted circulatory support protocol. Aortic insufficiency was graded on an interval scale (severe = 4, moderate = 3, mild = 2, trivial or none = 1). Kaplan-Meier estimates for long-term mortality at the follow-up were generated. We used a logistic regression model to identify risk factors for symptomatic heart failure. The overall median duration of LVAD support was 856.3 ± 430.8 days (range, 12-1,744 days). We did not observe a significant difference in long-term mortality in patients with aortic insufficiency ≥ 3 grade compared with patients with aortic insufficiency < 3 grade (P = 0.767; log-rank). Aortic insufficiency was associated with an increased risk for heart failure event after discharge (odds ratio, 4.12; confidence interval, 1.48-16.93; P = 0.005). Aortic insufficiency was an independent risk factor for symptomatic heart failure and was not associated with long-term mortality. Aortic insufficiency progression was associated with symptomatic heart failure.

Abstract 12931: Myocardial Regeneration in End-stage Heart Failure After Left Ventricular Unloading

Introduction: Left Ventricular Assist Devices (LVAD) decrease cardiac mechanical work and metabolic demand and may decrease cardiomyocyte oxidative stress, followed by cell cycle re-entry and cell regeneration. We tested whether LVAD long-term support is associated with myocardial regeneration. Methods: Viability fluorodeoxyglucose (18FDG) - positron-emission tomography scans were performed &gt;3 months after LVAD implantation and every 6 months thereafter. 4 patients aged 18-70 with end-stage non-ischemic (NICM, n=3) or ischemic cardiomyopathy (ICM, n=1) were included. Low metabolic activity myocardial regions of interest (ROI) at &lt;15th percentile of relative 18FDG signal intensity were identified on the baseline scan. Global signal and co-registered low-intensity ROIs were analyzed on subsequent scans vs. baseline. Results: LV ejection fraction ranged 0-35% at baseline. Two patients (LVAD speed 2660 rotations per minute - RPM, output 3.4-4.1 and 5.6-5.9 liters per minute (LPM), respectively) underwent 2 scans before cardiac transplantation, exhibiting borderline increased global signal (1-4%) and significantly increased 18FDG signal in the baseline low-intensity ROI on the follow-up scan (67.7, 75.7%). The other 2 patients (LVAD parameters: 5600 RPM/ 4.6-5.8 LPM; 9200 RPM/ 4.3-4.8 LPM) exhibited decreased global 18FDG signal (10-16%) and increased signal in the co-registered baseline low-intensity ROIs (1.7-21.5%) (Figure). Conclusions: LVAD long-term support is associated with a global decrease in myocardial 18FDG uptake signal over time, and with increased viability signal in baseline low-intensity ROIs, suggestive of myocardial regeneration in metabolically inactive regions. Future research is required to identify patient subgroups that are most likely to exhibit high regeneration potential upon long-term LVAD support.

Outcomes Following Discontinuation of Warfarin in Heartmate 3 Patients: A Multi-Center Review

Bleeding complications during left ventricular assist device (LVAD) support pose anticoagulation challenges as risk of discontinuation of anticoagulation, even in the setting of bleeding, may pose an increased risk of subsequent LVAD hemolysis or thrombosis. We assessed whether discontinuation of anticoagulation in HM3 patients whose bleeding concerns preventing anticoagulation would adversely impact outcomes. This multi-center, retrospective review included HeartMate 3 patients implanted between November 2016 and July 2019 for whom warfarin was discontinued. Patient characteristics, reason for anticoagulation discontinuation and subsequent adverse events were collected for all patients. The primary outcome was incidence of pump thrombosis. Secondary outcomes included bleeding events and overall survival. Ten patients were analyzed (80% male, 70% ischemic cardiomyopathy and 80% destination therapy). Preopertively, three patients required warfarin and 3 had a prior history of gastrointestinal bleeding (GIB). Reasons for anticoagulation discontinuation post HM3 placement included: GIB (N=5), hemorrhagic CVA (N=3), gross hematuria (N=1), hemothorax (N=1), and allergy (N=1). Four patients had concomitant Aspirin discontinuation. Time supported with HM3 off anticoagulation ranged from 69 to 961 days, representing 4,869 patient-days in total (Figure 1A). During this follow-up time, one patient experienced an embolic CVA attributed to left atrial appendage clot with subsequent hemorrhagic transformation, and one patient required device exchange for thrombosis. Bleeding also remained a common adverse event (N=5) despite the lack of anticoagulation. These data highlight the complicated hemocompatibility challenges associated with long-term LVAD support in a sub-group of patients. Discontinuation of both Aspirin and Warfarin can be considered in a select group of HM3 patients, but with judicious monitoring for early signs of adverse events.

Long-Term Outcomes of Heartware Left Ventricular Assist Device Decommissioning for Myocardial Recovery

Left ventricular assist device (LVAD) decommissioning reduces the risks associated with long-term LVAD support without subjecting patients to a major explantation operation. However, the long-term outcomes of this strategy are not known. Our unit's LVAD database was reviewed to identify patients who underwent LVAD decommissioning for myocardial recovery from 2009 to 2019. Friedman test was performed to compare left ventricle (LV) function grades over time and repeated measures ANOVA for ejection fraction (EF). Kaplan-Meier analysis was conducted to compare the survival of these patients with the LVAD bridged to transplant and all other LVAD patients. Among the 254 adult LVAD patients, 11 (4.3%) underwent decommissioning for myocardial recovery after assessment at low flow. The median support duration was 940 (IQR 646-1078) days and median follow-up duration 1425 (IQR 776-1774) days. 3 patients (27.3%) died during follow-up, 1 due to heart failure and 2 due to sepsis. 4 patients (36.4%) had LVAD explantation subsequently due to recurrent sepsis. This group's survival was comparable to that of the LVAD bridged to transplant group (p=0.7) and significantly better than that of the all other LVAD group (p=0.0015) (Figure 1). However, after decommissioning, their LV function gradually deteriorated (Figure 2). Selected patients with myocardial recovery would benefit from LVAD decommissioning with favourable long-term outcomes. However, they still face the potential risk of systemic infection and need to be regularly followed up for LV function monitoring and medical therapy optimisation.

Prognostic factors for heart recovery in adult patients with acute fulminant myocarditis and cardiogenic shock supported with extracorporeal membrane oxygenation

BackgroundExtracorporeal membrane oxygenation (ECMO) is an effective support method for acute fulminant myocarditis (AFM) with cardiogenic shock. However, deciding whether to bridge to a left ventricular assist device (LVAD) or to maintain ECMO support until heart recovery is still controversial. Material and methodsThis was a retrospective observational study from a single center. Eighty-eight adults with AFM and ECMO support between 2006 and 2018 were included. The primary endpoint was heart recovery without heart transplantation or long-term LVAD support. ResultsThe heart recovery group contained 43 patients, of whom 41 were discharged after being weaned off ECMO and the other two after LVAD. Five patients with heart transplants and one with long-term LVAD support were discharged, accounting for an overall survival of 55.7%. Multivariate logistic regression revealed that peak CK-MB level, severe intraventricular conduction disturbance (asystole) and malignant arrhythmia (VT or VF) were prognostic factors for nonrecovery (P = .027 and 0.017, respectively), while early intravenous immunoglobulin (IVIG) use before ECMO was highly likely to have a protective effect with a trend toward statistical significance (P = .079). A risk score was developed: 4 points for VT/VF/asystole, 1 point for every 100 μg/L increase in the peak CK-MB level, up to a maximum of 5 points, and −3 points for early IVIG use. The area under the receiver operating characteristic (ROC) curve (AUC) was 0.818. ConclusionHigh CK-MB levels and VT/VF/asystole in patients with AFM are associated with poor heart recovery. Early IVIG use shows a potentially protective effect.

Abnormalities of brain imaging in patients after left ventricular assist device support following explantation

The potential impact of long-term left ventricular assist device (LVAD) support on the brain remains unclear. This study aimed to investigate cerebral microvascular damage in patients after long-term LVAD implantation using magnetic resonance imaging (MRI). We reviewed the medical records of patients after continuous-flow LVAD implantation in our hospital from 2006 to 2016, who underwent brain MRI after LVAD explantation for either transplantation or recovery. Age- and sex-matched healthy controls and patients with chronic heart failure (CHF) were collected from our pooled MRI database. The presence of cerebral microbleeds (CMBs) and cortical superficial siderosis and the severity of white matter hyperintensity (WMH) and cerebral atrophy were compared between patients with prior LVAD and 2 control groups. This study included 49 patients with prior LVAD, 49 healthy controls, and 45 patients with CHF. CMBs and cortical superficial siderosis were detected in 98% (p < 0.001) and 31% (p < 0.001) of patients with prior LVAD, respectively. The number of CMBs was higher in patients with prior LVAD than in the 2 control groups. The severity of the WMH was higher in patients with prior LVAD than in healthy controls but similar to that in patients with CHF. Quantitative analyses of cerebral atrophy revealed a significantly higher bicaudate ratio and cella media index in patients with prior LVAD than in the 2 control groups. Patients after long-term LVAD support showed a higher prevalence of CMBs and cortical superficial siderosis and more severe cerebral atrophy than did controls. These findings may indicate cerebral microvascular damages in long-term LVAD support patients.

The Effect of Left Ventricular Assist Devices (LVAD) on Pulmonary Hypertension: A Single Center Review

Purpose Recently published case series have demonstrated that long-term LVAD support may reverse pulmonary hypertension in end-stage heart failure. This study's purpose was to review our local experience through right-heart catheterization follow-up of LVAD patients. Methods Patients were identified through the local VAD coordinator and our perioperative surgical database. Pre- and peri-operative data were captured from our database while catheterization data were gathered from electronic records. Pulmonary hypertension was defined as having a pre-implant mean pulmonary artery (PA) pressure >25 mmHg. Hemodynamics were captured from 1 year prior to LVAD insertion to loss of follow-up or death. A population-averaged panel-data model using generalized estimating equation (GEE) was used to determine the effects of pre-operative variables on longitudinal pulmonary hemodynamics . Results From 2004 to 2018, 95 patients underwent LVAD implantation at our institution. Hemodynamics were available on 72 of these patients, of which 52 had pre-operative pulmonary hypertension. Average follow-up was 697±574 days. Mean PA pressures over time are represented in Figure 1. Most had normalization of their PA pressures following LVAD implantation and this process occurred within the first year in the majority of patients. Following GEE model fitting, no pre-operative variables appeared to affect post-operative PA pressures significantly, including whether the patient was diagnosed with pulmonary hypertension prior to LVAD implantation. Cardiac risk factors as well as pre-operative ejection fraction also did not appear to significantly affect changes in post-operative PA pressures. Conclusion In this single-center retrospective analysis, LVAD implantation appeared to lower pulmonary artery pressures in patients with end-stage heart failure. The development of pre-operative pulmonary hypertension and other cardiac risk factors did not appear to significantly affect this process.

Abstract TP186: Impact of Long-term Left Ventricular Assist Device Support on Human Brain: A Case-control Study Using MRI

Introduction: Left ventricular assist device (LVAD) implantation improves the prognosis of patients with severe heart failure; however, the potential impact of long-term LVAD support on the brain remains unclear. The aim of this case-control study was to examine the characteristics of brain MRI in patients after long-term LVAD support. Methods: We retrospectively reviewed consecutive adult patients who underwent continuous-flow LVAD implantation in our hospital from 2010 to 2017, and those who underwent brain MRI after successful LVAD explantation were enrolled in this study. Age- and sex-matched control subjects (1:1) were selected from a pool of normal subjects who underwent MRI examination for screening purposes. The number and location of cerebral microbleeds (CMBs) and superficial siderosis, and the severity of white matter hyperintensity (WMH) and cerebral atrophy were compared between LVAD patients and controls. Results: We enrolled 49 LVAD patients and 49 controls. In LVAD patients, cardiomyopathy (84%) was the most common underlying heart disease. Heart transplantation was performed in 46 patients (94%) and 3 removed LVAD due to myocardial recovery. The median age was 41 years (range 19-66), and the median LVAD support time was 32 months (4-52). Nineteen patients developed symptomatic stroke (10 ischemic and 10 hemorrhagic) during LVAD support. Except for one, almost all (98%) LVAD patients had one or more CMBs, and the number of CMBs was much higher in the LVAD patients (mean, IQR: 7, 3-11 vs 0, 0-0: p&lt;0.001) than controls. Superficial siderosis was positive in 15 (31%) of LVAD patients, but not in controls. The severity of WMH was significantly higher both in deep subcortical (p=0.01), and periventricular region (p=0.04) than controls. In quantitative analyses of cerebral atrophy, bicaudate ratio (0.105±0.023 vs 0.089±0.019: p&lt;0.001) and cella-media index (0.160±0.033 vs 0.141±0.024: p&lt;0.001) were significantly higher in LVAD patients than controls. Conclusions: Patients after long-term LVAD support showed a high prevalence of CMBs and superficial siderosis, and more severe WMH and cerebral atrophy compared to age- and sex-matched controls. Long-term LVAD support may cause cerebral small vessel disease.

Severe LVAD-related infections requiring surgical treatment: Incidence, predictors, effect on survival, and impact of device selection.

Left ventricular assist devices (LVADs) are being used more frequently for treating refractory, advanced heart failure. However, infection remains a frequent complication. In this study, we analyzed the incidence of severe infections in LVAD recipients to determine its impact on survival. From May 2009 through March 2016, 437 patients with advanced heart failure underwent implantation of a continuous-flow LVAD (n = 314, HeartMate II LVAD [Abbott Laboratories, Abbott Park, IL]; n = 123 HeartWare HVAD [Medtronic, Minneapolis, MN]). We analyzed the rate of severe device infection requiring surgical intervention or involving sepsis and the impact of severe infection on outcomes in patients on long-term LVAD support. Infection occurred in 244 patients (HeartMate II, n = 186; HVAD, n = 58); severe infections developed in 160 patients (HeartMate II, n = 119; HVAD, n = 41). HeartMate II recipients had 344 severe infection events (0.63 events per patient-year [EPPY]), whereas HeartWare recipients had 89 severe infection events (0.42 EPPY; P = 0.047). HeartMate II recipients had a higher incidence of pump infections (P < 0.001). Severe infections did not significantly affect survival (P = 0.42). Although HeartMate II patients had a significantly higher incidence of pump infections requiring surgical treatment, survival was not adversely affected. The difference in postoperative infection rates may be an important factor in device type selection.

TAVR in Patients with Left Ventricular Assist Device: Case Report and Literature Review

ABSTRACT The use of left ventricular assist devices (LVADs) as a bridge-to-transplant or destination therapy in patients with end-stage heart failure has been increased during the last years. However, a potential obstacle to the success of long-term LVAD support is represented by the development of de novo aortic valve lesions leading to aortic regurgitation or, more rarely, to commissural fusion and stenosis. The paper addresses the main pathophysiological factors in the development of aortic valvular regurgitation in patients with LVAD and describes an updated review of all transcatheter aortic valve replacement (TAVR) cases to treat aortic regurgitation currently available. We also report on a case of a patient with a Jarvik 2000 requiring transcatheter aortic valve replacement for aortic regurgitation. The procedure was performed using a 31-mm CoreValve prosthesis. The first check after the positioning of the prosthetic valve revealed a good result. However, a second 10-min check, performed as per protocol at the end of the procedure, showed a sliding of the prosthetic valve downward toward the apex of the left ventricle with a severe periprosthetic regurgitation. Therefore, a second 31-mm CoreValve was deployed within the previous valve prosthesis and a 10-min check revealed a stable position and a mild residual leak. The management of LVAD patients with aortic regurgitation remains challenging. Although transcatheter techniques have demonstrated feasibility in these patients, technical adjustments and further expertise are needed to optimize these procedures.

Effect of Continuous-Flow Mechanical Circulatory Support on Microvasculature Remodeling in the Failing Heart.

Left ventricle (LV) unloading caused by a left ventricular assist device (LVAD) has been shown to enhance reverse LV remodeling in end-stage cardiomyopathy. Several reports consistently suggest that a pulsatile-flow LVAD has more profound effects compared to continuous-flow LVAD, though the responsible mechanisms are not fully understood. We hypothesized that arterial pulsatility, being affected by the type of LVAD, may affect microvasculature and functional/pathological LV remodeling in end-stage cardiomyopathy. The study included 18 patients with chronic heart failure who underwent LVAD implantation. Eight patients were implanted with pulsatile-flow LVAD, and 10 patients were implanted with continuous-flow LVAD. The results of serial echocardiograms and histopathological assessment of transmural LV tissues, which were collected during the implantation and removal of LVADs, were compared between the groups. The results of echocardiography showed that LV systolic dimension and LV ejection fraction improved greatly in the pulsatile-flow LVAD group compared to the continuous-flow LVAD group. Histological analysis showed that in both groups, increased microvasculature density and decreased cardiomyocyte size during LVAD support had no significant difference. In contrast, only the patients with continuous-flow LVADs had presented with significant increase in α-smooth muscle actin (α-SMA)-positive layer thickness and the number of proliferating cell nuclear antigen (PCNA)-positive cells of myocardial arterioles. We concluded that the use of long-term continuous-flow LVAD support, having less pulsatility, had induced more thickening to the medial layer of myocardial arterioles compared to the use of pulsatile-flow LVADs. Our findings suggest that the pathological impairment of myocardial microvascular structure during continuous-flow LVAD support may be a novel mechanism which accounts for the difference in LV remodeling depending on the type of LVAD.

Long-term outcomes following thrombectomy for acute ischemic stroke in patients with a left ventricular assist device: a case series and literature review

Left ventricular assist devices (LVADs) were developed for the treatment of patients with severe heart failure (HF) as a bridge to heart transplantation (HT). Although long-term LVAD support results in substantial improvements, their long-term use often leads to severe acute ischemic stroke (AIS). Serious neurological events make it difficult to continue LVAD support, and these patients are excluded as candidates for HT. AIS remains a challenging problem in patients receiving LVAD support. Recently, although thrombectomy has been established in selected patients who are independent, it has not been established in patients who are not completely independent, such as those with LVAD support. We describe four AIS patients with severe HF who were implanted with an LVAD as a bridge to HT. Five mechanical thrombectomies were performed for AIS associated with an LVAD in four patients. A literature review is presented and compared to the present results. Good recanalization was achieved in all patients. In three cases, marked neurological improvement was observed, and modified Rankin Scale (mRS) scores were maintained without deterioration. The median total follow-up period was 592days. In one patient, HT was successfully performed after thrombectomy. Currently, two of the patients without neurological deficits are awaiting HT. Embolism is a major problem encountered by patients under LVAD support while waiting for an HT. Thrombectomy for AIS associated with LVAD support is a useful and safe treatment modality. It is possible to maintain a reasonable mRS score in patients who are not completely independent.

Favorable Effects on Pulmonary Vascular Hemodynamics with Continuous-Flow Left Ventricular Assist Devices Are Sustained 5 Years After Heart Transplantation.

It is unclear whether pulmonary hemodynamics improvement with left ventricle unloading with left ventricular assist devices (LVADs) is sustained long term after heart transplant (HT). We sought to assess the effects on pulmonary vascular hemodynamics during continuous-flow (CF-LVAD) and pulsatile flow (PF-LVAD) support up to 5 years after HT. Invasive hemodynamics were evaluated before LVAD, before HT, and at 3 months, 1, and 3-5 years posttransplant. Thirty-eight patients were included in the study and divided into two groups according to the type of LVAD support. The two groups were well matched in age and gender. Mean pulmonary artery pressure (PAPm) and systolic PAP (PAPs) improved significantly in the PF-LVAD group (40 ± 10.6 to 19.8 ± 4.4 mm Hg and 62.7 ± 14.9 to 31.8 ± 5.9 mm Hg, respectively) and in the CF-LVAD group (37.4 ± 11.6 to 22.4 ± 7.7 mm Hg and 53.7 ± 18.0 to 34.6 ± 11.8 mm Hg, respectively). Reductions in PAPm and PAPs were more pronounced in PF-LVAD group than in CF-LVAD group (p = 0.005 and p = 0.03, respectively). After HT, the improvement in PAPm and PAPs was sustained after 3-5 years in patients who received PF-LVAD (22.6 ± 6.5 and 32.2 ± 9.2 mm Hg, respectively) and in patients who received CF-LVAD (22.2 ± 8.4 and 33.8 ± 9.6 mm Hg, respectively). In conclusion, long-term LVAD support resulted in significant improvement in PAPm and PAPs regardless of the pump generation. The improvement in hemodynamics observed during LVAD support was sustained 3-5 years posttransplant.