Left ventricular assist device insertion and open abdominal aortic aneurysm repair in same admission for an end-stage heart failure patient

Patients suffering from end-stage heart failure also suffer from multiple cardiovascular comorbidities such as abdominal aortic aneurysm (AAA). Mechanical support with left ventricular assist device with open repair of AAA repair has rarely been reported in literature. The authors describe a 60-year-old male with end-stage heart failure and a symptomatic AAA with sequential left ventricular assist device insertion and open AAA repair with aortic cross-clamping.     

Reversal of pulmonary hypertension in paediatric patients with restrictive cardiomyopathy

Left ventricular assist devices can reverse pulmonary hypertension in cardiac transplant candidates with heart failure with a reduced ejection fraction. Whether a similar approach is applicable in restrictive cardiomyopathy is uncertain. We report the successful implantation of a Medtronic HVAD left ventricular assist device in a bridge-to-candidacy concept in 2 paediatric patients with restrictive cardiomyopathy.     

Successful Non-Heart-Beating Donor Organ Retrieval in a Patient with a Left Ventricular Assist Device

Non-heart-beating donors (NHBD) represent an option to expand the organ supply with good results. We report a donor patient with a left ventricular assist device (LVAD) due to dilated cardiomyopathy in which controlled NHBD was performed. Due to the LVAD, a modified procurement technique was utilized. The liver and kidneys were procured and successfully transplanted. Patients and grafts are alive and well. Successful organ retrieval can be achieved on selected cases of NHBD with LVADs in which modifications of the procurement technique are implemented without jeopardizing the procurement and not increasing preservation injury.     

Prevention of Right Heart Failure After Left Ventricular Assist Device Implantation by Phosphodiesterase 5 Inhibitor

Right ventricular (RV) function immediately after left ventricular assist device (LVAD) implantation is a crucial prognostic factor. RV failure is linked to increased mortality and worse outcome. A phosphodiesterase 5 inhibitor, sildenafil, was shown to decrease pulmonary vascular resistance and pulmonary artery pressure post‐LVAD. We report on a series of heart failure patients, and the effect of sildenafil on the incidence of RV failure after LVAD implantation. We retrospectively analyzed the data of end‐stage heart failure patients who underwent LVAD implantation with pulmonary hypertension and RV dysfunction prior to surgery. Patients were divided into two groups; group 1: patients who received sildenafil perioperatively, and group 2: patients who did not receive sildenafil. Hemodynamic and echographic data were collected before and after surgery. Fourteen patients were included, 8 patients in group 1 and 6 in group 2. Sildenafil was administered with a mean dose of 56.2 ± 9.4 mg in group 1 and was able to significantly reduce right heart failure incidence, and to demonstrate a significant reduction in pulmonary vascular resistance, pulmonary artery pressure, transpulmonary gradient, and a significant increase in cardiac output. In conclusion, sildenafil seems to have a promising role perioperatively in preventing acute RV failure postsurgery in patients with RV dysfunction and pulmonary hypertension, requiring LVAD therapy.     

Left ventricular mechanical support with the Impella Recover left direct microaxial blood pump: a single-center experience

The Impella Recover left direct (LD) is a new intravascular microaxial blood pump, intended as a short-term mechanical support especially in case of acutely reduced left ventricular function. From September 2002 to October 2004, Impella was used to support 12 patients: six patients were supported as bridge-to-heart transplant (HTx); three patients were treated for fulminant acute myocarditis, and three patients for postcardiotomy low-output syndrome. Mean support time was 8.8 +/- 2.3 days. Overall mortality was 50%. Four patients were successfully HTxed; two patients supported as bridge-to-HTx died on left ventricular assist device. Two patients with myocarditis died of septic shock; two patients in the group of postcardiotomy died of multiorgan failure. The latter two patients were slowly weaned from the device, and at 3-months follow-up showed good improvement of the left ventricular function. Our initial experience with Impella Recover LD as mechanical support for patients in cardiogenic shock of various etiology is promising, yielding a good survival in a population of particularly compromised patients.     

Development of a Direct Mechanical Left Ventricular Assist Device for Left Ventricular Failure

Abstract: We have developed a direct mechanical left ventricular assist device (DMLVAD) for severe left ventricular failure. The DMLVAD was attached to the left ventricle and compressed the heart by a pneumatic driving unit. In a mock circulation model with an extracted non-beating heart, a cardiac output (CO) of 1.93 L/min was obtained at a driving pressure of 200 mm Hg. In a canine left ventricular failure model induced by injection of sodium hydroxide into the myocardium, the systolic arterial pressure, systolic left ventricular pressure, maximum LV dP/dt, peak flow, and CO increased by 21, 24, 58, 144, and 37%, respectively. The mean left atrial pressure also decreased by 15% when the DMLVAD was driven. These effects were most prominent when the mean left atrial pressure was over 15 mm Hg, and the driving pressure was over 100 mm Hg. Compression at late systole was more effective in obtaining greater CO. We suggest that the DMLVAD could be an optional circulatory assist device for patients with left ventricular failure awaiting heart transplantation.     

Impact of left ventricular assist device therapy on the cardiac proteome and metabolome composition in ischemic cardiomyopathy

The changes in the myocardial proteome and metabolome associated with left ventricular assist device (LVAD) therapy in patients with ischemic cardiomyopathy (ICM) are poorly characterized. We investigated the impact of mechanical unloading following LVAD therapy on the myocardial proteome and metabolome. Matched samples of 5 patients’ myocardial tissue, harvested at the time of LVAD implant (“pre-LVAD”) or heart transplant (“post-LVAD”), were studied by quantitative proteomics and metabolomics as well as being probed for T-tubule structure and connexin-43 distribution. Moreover, pre-LVAD proteome profiles of ICM context were bioinformatically compared to pre-LVAD proteome profiles of dilated cardiac myopathy (DCM). More than 2120 proteins were reliably identified and quantified in paired patient samples. LVAD therapy led to proteomic remodeling, including reduced levels of α-1-antichymotrypsin together with an overall decrease of immune response proteins and an increase of proteins involved in membrane biology. Metabolomics highlighted increased glucose and glucose-6-phosphate levels in the left ventricle upon LVAD therapy. Wheat germ agglutinin staining demonstrated improved T-tubule structure. Connexin-43 displayed a trend for more pronounced intercalated disc localization. In comparing pre-LVAD proteome profiles of ICM context with pre-LVAD proteome profiles of dilated cardiac myopathy (DCM), we noticed an overrepresentation in ICM of proteins associated with humoral immune response. Our findings underline an impact of LVAD therapy on left ventricular biology in ICM. The proteomic, metabolomic, and structural alterations described here are typically associated with cardiac recovery. On the molecular level, our findings indicate the possibility of cardiac remodeling under LVAD therapy in ICM.     

Acute clinical deterioration in a patient with end-stage dilated cardiomyopathy and left ventricular thrombus formation

The case of a 17-year-old male patient with severe end-stage dilated cardiomyopathy and a large thrombus formation within the cavum of the left ventricle is reported. After an acute thrombectomia combined with a partial left ventriculectomy (Batista procedure), the patient was successfully treated with an appropriate left ventricular assist device (LVAD) system using a centrifugal nonocclusive pump (Biomedicus, Medtronic, Anaheim, CA, U.S.A.). Mechanical support was removed on Day 9, and the patient was discharged from the hospital on Day 19. The effectiveness of emergency mechanical support in patients with very unfavorable prognoses is discussed.     

Implantable left ventricular assist device for treatment of pulmonary hypertension in candidates for orthotopic heart transplantation—a preliminary study

Objectives: Elevated pulmonary vascular resistance (PVR) unresponsive to pharmacological intervention is a major limitation in heart transplantation (HTX). The post-operative course of these patients is associated with an increased risk of life-threatening right heart failure. We evaluated the efficiency of an implantable left ventricular assist device (LVAD) to decrease PVR by unloading the left ventricle and to lower the risk of later orthotopic HTX. Methods: Six patients with end-stage heart failure (NYHA class IV) and ’fixed‘ pulmonary hypertension (PVR 5.7±0.7, range 4.4–6.5 Wood units) were analyzed. Despite maximal pharmacological intervention at initial evaluation (oxygen inhalation, nitrates, alprostadil infusion) PVR could not be reduced to under 2.5 Wood units. Four patients received a TCI Heartmate, one patient a Novacor, and one patient a Jarvik 2000. Results: All patients survived the LVAD implantation, four patients could be discharged from hospital. Cardiac index and pulmonary artery pressure values returned to normal during the early post-operative phase. After a mean support time of 191±86 days PVR had fallen to 2.0±1.2 (range 0.8–3.6) Wood units. All patients could be bridged to transplantation, one patient died 3 months after transplant, five patients are still alive after a mean follow-up of 16.2±10.5 months. Conclusions: Mechanical support using an implantable LVAD is a very efficient approach with an acceptable risk to treat severe pulmonary hypertension in end-stage heart failure patients before HTX. Adequate reduction of PVR can be expected within 3–6 months. Subsequent HTX is associated with a good outcome.     

Clinical Outcomes of Patients Treated With Pulmonary Vasodilators Early and in High Dose After Left Ventricular Assist Device Implantation

Right ventricular failure (RVF) is common after left ventricular assist device (LVAD) implantation and a major determinant of adverse outcomes. Optimal perioperative right ventricular (RV) management is not well defined. We evaluated the use of pulmonary vasodilator therapy during LVAD implantation. We performed a retrospective analysis of continuous‐flow LVAD implants and pulmonary vasodilator use at our institution between September 2004 and June 2013. Preoperative RVF risk was assessed using recognized variables. Sixty‐five patients (80% men, 50 ± 14 years) were included: 52% HeartWare ventricular assist device (HVAD), 11% HeartMate II (HMII), 17% VentrAssist, 20% Jarvik. Predicted RVF risk was comparable with contemporary LVAD populations: 8% ventilated, 14% mechanical support, 86% inotropes, 25% BUN >39 mg/dL, 23% bilirubin ≥2 mg/dL, 31% RV : LV (left ventricular) diameter ≥0.75, 27% RA : PCWP (right atrium : pulmonary capillary wedge pressure) >0.63, 36% RV stroke work index <6 gm‐m/m²/beat. The majority (91%) received pulmonary vasodilators early and in high dose: 72% nitric oxide, 77% sildenafil (max 200 ± 79 mg/day), 66% iloprost (max 126 ± 37 μg/day). Median hospital stay was 26 (21) days. No patient required RV mechanical support. Of six (9%) patients meeting RVF criteria based on prolonged need for inotropes, four were transplanted, one is alive with an LVAD at 3 years, and one died on day 35 of intracranial hemorrhage. Two‐year survival was 77% (92% for HMII/HVAD): transplanted 54%, alive with LVAD 21%, recovery/explanted 2%. A low incidence of RVF and excellent outcomes were observed for patients treated early during LVAD implantation with combination, high‐dose pulmonary vasodilators. The results warrant further investigation in a randomized controlled study.     

Combined autologous cellular cardiomyoplasty using skeletal myoblasts and bone marrow cells for human ischemic cardiomyopathy with left ventricular assist system implantation: Report of a case

Myocardial regeneration therapy shows great promise as a treatment for heart failure. We recently introduced combined autologous cellular cardiomyoplasty with skeletal myoblasts and bone marrow cells as a treatment for human ischemic cardiomyopathy. We report the results of our first clinical trial of this technique, used to treat a patient with severe heart failure caused by ischemic cardiomyopathy who was being managed with a left ventricular assist system (LVAS). After combined cell transplantation, the patient showed signs of improved cardiac performance and angiogenesis, and reduced fibrosis.     

Intermittent atrial level right-to-left shunt with temporary hypoxemia in a patient during support with a left ventricular assist device

We report a 56-year-old male patient developing hypoxemia after surgical replacement of infected valves of a left ventricular assist device (LVAD, Novacor) which had supported him during the previous 15 months. Contrast transesophageal echocardiography (TEE) revealed an atrial septal defect with intermittent right-to-left shunt across a patent foramen ovale. We postulate that the shunt detected in this patient occurred as a consequence of reduced pulmonary vascular compliance due to positive end-expiratory pressure (PEEP) and an increase of mean intrathoracic pressure. Furthermore, we hypothesize that synchronized LVAD operation exacerbates any potential right-to-left shunt due to the profound left ventricular unloading which occurs during LVAD support. In this first report of a right-to-left shunt from a previously unrecognized patent foramen ovale in a Novacor patient, the subsequent transient hypoxemia could be managed by avoiding PEEP of more than 3 mmHg, and mean airway pressure of more than 11 mmHg and by careful volume replacement in order to prevent the pump from completely emptying the left ventricle (LV) and the left atrium (LA). Thus, prior to every LVAD implantation a transesophageal contrast echocardiography with Valsalva maneuver should be performed to identify intracardiac right-to-left shunt.     

Experimental Assessment of Right Ventricular Function in Normal Pigs with a Left Ventricular Assist Device

Abstract: Right ventricular (RV) failure during the use of a left ventricular assist device (LVAD) is the leading cause of death in circulatory support patients. Previous work, both experimentally and clinically, has shown the difficulties in predicting the behavior of the right ventricle at the start of LVAD. An experimental study has been designed to evaluate RV functional changes during LVAD and its relation to preload changes. The model used adult mongrel pigs (n = 10). Right ventricular functional parameters were measured with a thermodilution RV ejection fraction catheter. The left ventricle was supported by a Nippon Zeon blood pump. Two groups were studied, the first one was the LVAD–off group (n = 5) and the other was the LVAD–on group (n = 5) which was supported by LVAD at maximum flow. Change of cardiac output, mean pulmonary artery pressure (PAP), RV stroke work, and RV ejection fraction in both groups were not significantly different. However, the relationship between right ventricular end–diastolic pressure (RV–EDP) and right ventricular stroke volume (RVSV) was significantly changed at a high level of RV–EDP. When RV–EDP was over 6. 5 mm Hg in the LVAD–off group, RVSV decreased to 52. 3 ± 11. 5 ml while in the LVAD–on group, RVSV increased to 97. 2 ± 22. 0 ml. The change in PAP in the LVAD–on group was lower than in the LVAD–off group. We conclude that, at the volume overload state, LVAD can reduce the afterload of the right ventricle and maintain Frank–Starling's effect, thus having a beneficial effect on right ventricular performance.     

Reversibility of fixed pulmonary hypertension in left ventricular assist device support recipients

Objective: Conflicting data still exist concerning the reversibility of secondary severe ‘fixed’ pulmonary hypertension (PH) by the use of left ventricular assist device (LVAD) support in terms of time necessary to provide a bridge to ‘transplantability’. Methods: We retrospectively reviewed 145 patients with heart failure and severe PH treated by LVAD support between 2000 and 2009. There were 133 men (91.7%) and 12 women (8.3%) with a mean age of 52.95 ± 12.01 years. Patients were divided into two groups depending on preoperative PH reversibility. Fixed PH was defined by a mean pulmonary arterial pressure (mPAP) >25 mmHg, a pulmonary vascular resistance (PVR) >2.5 Wood Unit (WU) and a transpulmonary gradient (TPG) >12 mmHg, despite pharmacological treatment. Results: Fifty-six patients had fixed PH (group A) and 89 reversible PH (group B). Only 27 patients of group A underwent right heart catheterization evaluation during LVAD support; the remaining 29 patients had other contraindications to heart transplantation (HTx). The 27 patients were divided into three subgroups on the basis of examination time during LVAD support: <6 months (11 patients), between 6 and 12 months (six patients) and >12 months (10 patients). The mPAP, PVR, and TPG decreased significantly during LVAD support (mPAP, 37.26 ± 6.35 mmHg vs 21.00 ± 7.51 mmHg, p = 0.007; PVR, 3.49 ± 1.47 WU vs 1.53 ± 0.66 WU, p = 0.000; and TPG, 15.04 ± 5.22 mmHg vs 7.78 ± 3.21 mmHg, p = 0.019). A significant reduction of all parameters was observed during the first 6 months and later on there was no further decrease. There were no significant differences between the three subgroups (mPAP, p = 0.680; PVR, p = 0.723; and TPG, p = 0.679) in terms of time of reversibility. LVAD support allowed 19 patients to be transplanted. Conclusions: Patients with fixed PH can be treated with LVAD support. Our data suggest that 6 months after LVAD implantation it is possible to observe an important reduction of PH and evaluate the potential transplantability of patients. Longer support does not add any effect of LVAD on PH.     

Comparison of Continuous‐Flow and Pulsatile‐Flow Blood Pumps on Reducing Pulmonary Artery Pressure in Patients With Fixed Pulmonary Hypertension

Pulmonary hypertension (PH) is considered as a risk factor for morbidity and mortality in patients undergoing heart transplantation. Recently, left ventricular assist device (LVAD) implantation has been increasingly used in reducing pulmonary artery pressure (PAP) in patients with PH unresponsive to medical therapy. Herein, we aimed to compare the efficacy of continuous‐flow and pulsatile‐flow blood pumps on the improvement of PH in mechanical circulatory support patients. Twenty‐seven patients with end‐stage heart failure who underwent LVAD implantation surgery were enrolled. Fifteen of them (55.6%) had continuous‐flow pump (HeartWare Ventricular Assist System, HeartWare, Inc., Miramar, FL, USA), and 12 of them (44.4%) had pulsatile pump (Berlin Heart EXCOR ventricular assist device, Berlin Heart AG, Berlin, Germany). The efficacy of LVADs on the improvement of PH was compared between continuous‐flow and pulsatile pumps by the evaluation of systolic PAP, tricuspid annular plane systolic excursion (TAPSE), right ventricular systolic motion (RVSM), right ventricular ejection fraction (RVEF), and grade of tricuspid insufficiency (TI) for each of the study participants. All of the 15 patients who underwent continuous‐flow blood pump implantation surgery (Group 1) were male with a mean age of 46.9 ± 11.7 years, and in pulsatile‐flow blood pump implanted participants (Group 2), the mean age was 40.6 ± 16.8 years, all of whom were also male (P = 0.259). Mean follow‐up was 313.7 ± 241.3 days in Group 1 and 448.7 ± 120.7 days in Group 2 (P = 0.139). In Group 1, mean preoperative and postoperative systolic PAP were measured as 51.7 ± 12.2 mm Hg and 22.2 ± 3.4 mm Hg, respectively, while those in Group 2 were 54.5 ± 7.5 mm Hg and 33.9 ± 6.4 mm Hg, respectively. A significantly greater decrease in systolic PAP was noticed in patients with continuous‐flow blood pumps (P = 0.023); however, no statistically significant difference was found when we considered the change in TAPSE between study groups (P = 0.112). A statistical significance in the alteration of RVEF, RVSM, and the grade of TI during study visits was not found between the study groups (P = 0.472, P = 0.887, and P = 0.237, respectively). Although the two studied types of LVADs were found to be effective in reducing PAP in heart transplantation candidates with PH, lesser postoperative systolic PAP values were achieved in patients who underwent continuous‐flow pump implantation surgery.     

A detailed explantation assessment protocol for patients with left ventricular assist devices with myocardial recovery

Open in a separate window OBJECTIVESLeft ventricular assist device (LVAD) implantation for end-stage heart failure patients has been on the rise, providing a reliable long-term option. For some LVAD patients, longer term LV unloading leads to recovery; hence, the need for evaluating potential myocardial recovery and weaning eligibility has emerged.METHODSAll patients who underwent contemporary LVAD explantation at our institution between 2009 and 2020 were included in the study. Patients in New York Heart Association I, left ventricular ejection fraction >40%, a cardiac index >2.4 l/min and a peak oxygen intake >50% predicted underwent a 4-phase weaning assessment. A minimally invasive approach using a titanium plug was the surgery of choice in the most recent explants. Kaplan–Meier curves were used to estimate the survival at 1 and 5 years.RESULTSTwenty-six patients (17 HeartMate II, 9 HeartWare) underwent LVAD explantation after a median 317 days of support [IQ (212–518)], range 131–1437. Mean age at explant was 35.8 ± 12.7 years and 85% were males. Idiopathic dilated cardiomyopathy was the underlying diagnosis in 70% of cases. Thirteen (48%) patients were on short-term mechanical circulatory support and 60% required intensive care unit admission prior to the LVAD implantation. At 1 year, Kaplan–Meier estimated survival was 88%, whereas at 6 years, it was 77%. The average left ventricular ejection fraction at 1 year post-explant was 44.25% ± 8.44.CONCLUSIONSThe use of a standardized weaning protocol (echocardiographic and invasive) and a minimally invasive LVAD explant technique minimizes periprocedural complications and leads to good long-term device-free survival rates.     

Left ventricular hypertrophy and arterial wall thickening in children with essential hypertension

Objective Our aim was to determine the prevalence of left ventricular hypertrophy (LVH) and increased intima-media thickness (IMT) in Caucasian children with newly diagnosed, untreated essential hypertension (EH).Participants Our study cohort consisted of 72 children with EH (mean age: 14.5 years; range: 5–18 years). The control groups consisted of 103 age-matched, healthy children.Methods We evaluated the left ventricular mass (LVM), intima-media thickness in the carotid (cIMT) and superficial femoral (fIMT) arteries, 24-h ambulatory blood pressure, and biochemical cardiovascular risk factors.Results Of the hypertensive children examined, 41.6% had LVM above the 95th percentile, and 13.2% had LVM above 51 g/m^2.7. Of the hypertensive subjects, the cIMT was above 2 SDS of normal values in 38.8%, and the flMT was above 2 SDS of normal values in 17.5%. Patients with LVM above 51 g/m^2.7 had a higher birth weight than other patients. LVM, cIMT, and fIMT correlated with 24-h SBP and pulse pressure; LVM also correlated with homocysteine and serum uric acid concentrations. fIMT correlated with low Aprotein A1 (ApoA1), higher ApoB and C reactive protein, and daily sodium excretion. Step-wise regression analysis revealed that serum uric acid and higher birth weight were predictors for LVM, pulse pressure was a predictor for cIMT, and ApoB was a predictor for fIMT.Conclusions A significant number of adolescents with EH already had cardiovascular damage at diagnosis. LVM and markers of arterial injury correlate with SBP, biochemical, and perinatal cardiovascular risk factors. Serum uric acid and higher birth weight are predictors of LVM.