Left Ventricular Assist Device Implantation Research Articles

Vasopressor-Inotropic Score: Review of Literature.

Patients undergoing cardiac surgery often receive vasopressor and inotropic medications during the surgical procedure and during intensive care unit (ICU) management following surgery. Patients with cardiogenic shock, septic shock, and other clinical disorders associated with shock also receive vasopressor medications during their ICU care. The level of support and the duration of support are likely associated with outcomes, including mortality and new organ dysfunction, such as acute kidney injury. The vasopressor-inotropic score provides a simple method to determine the level of support during the care of these patients; this score includes the infusion rates of norepinephrine, epinephrine, dopamine, dobutamine, and other inotropic medications. It has been studied in patients undergoing cardiac surgery, coronary artery bypass grafting, cardiac transplantation, left ventricular assist device implantation, septic shock, and traumatic brain injury. Higher scores are associated with poor outcomes and complications during ICU care. The studies analyzed in this review demonstrate the utility of the vasopressor-inotropic score in a variety of clinical disorders associated with shock. Electronic medical record systems should develop algorithms to calculate this score and provide continuous up-to-date measurements. This could help clinicians identify patients at risk for mortality and important complications, such as acute kidney injury.

Feasibility of a Multidomain Resiliency Assessment in Patients with Advanced Heart Failure Requiring Surgery: A Pilot Study.

The resiliency of patients who have advanced heart failure (HF) and undergo a physical stressor such as heart transplantation or left ventricular assist device implantation has yet to be studied in the physical, cognitive, and psychosocial domains. The primary aim of this pilot study was to assess the feasibility of a multidomain resiliency assessment in patients who have advanced HF and require surgery. A battery of assessments in each of the domains was completed at baseline before surgical intervention, after intensive care discharge, and 3 and 6months after surgery. Feasibility was assessed through completion rates, time required to complete the assessments, and qualitative feedback from assessors. Although various completion rates were noted at different time points, high completion rates were seen for grip strength, the modified Fried frailty phenotype, and the Montreal Cognitive Assessment. Additionally, when controlled for patients who were medically restricted from physical function, the Short Physical Performance Battery, gait speed, and the 30-second chair stand test also had high completion rates. A trend toward return to baseline status or an improvement in baseline status was observed in all physical and cognitive assessments and most psychosocial assessments at 3 and 6months. Minimal change was noted in the Brief Resilience Scale questionnaire. This pilot study demonstrates that a multidomain assessment of resiliency is feasible in patients with advanced HF. Future studies are needed to help determine specific assessments or patient factors that would help predict positive postsurgical outcomes in this population. This study has implications for clinical practice on the most feasible assessments in multiple domains for patients who have advanced HF and are being evaluated for heart transplantation or left ventricular assist device.

Neutrophil Extracellular Trap Formation in Advanced Heart Failure Patients-Preliminary Report.

In end-stage heart failure, which is characterized by persistent or progressive ventricular dysfunction despite optimal medical therapy, a left ventricular assist device (LVAD) can be beneficial. Congestive heart failure provokes inflammatory and prothrombotic activation. The aim of this study was to evaluate the serum concentration of citrullinated histone 3 (CH3) representing neutrophil extracellular trap (NET) formation in patients referred for LVAD implantation. There were 10 patients with a median age of 61 (57-65) years enrolled in a prospective single-center analysis who underwent LVAD implantation. The CH3 plasma concentration was measured preoperatively and on the 1st and 7th postoperative days, followed by control measurements on the median (Q1-3) 88th (49-143) day. The preoperative CH3 concentration strongly correlated with brain natriuretic peptide (r = 0.879, p < 0.001). Significant differences in CH3 serum concentration were observed between pre- and postoperative measurements, including an increase on the first postoperative day (p < 0.001), as well as a decrease on the seventh day (p = 0.016) and in follow-up (p < 0.001). CH3 concentration, as a marker of NET formation, decreases after LVAD implantation.

Enhancing Safety in Left Ventricular Assist Device Implantation: Laparoscopic Technique for Driveline Tunneling.

Advancements in left ventricular assist device (LVAD) technologies have significantly lowered morbidity and mortality in patients with end-stage heart disease; however, they still carry significant risks. Though infrequent, intraabdominal injury during driveline tunneling can be catastrophic. Laparoscopic visualization can reduce these risks, especially benefiting patients with lower body mass indexes and thin abdominal walls. We present two cases of laparoscopic driveline tunneling. The laparoscopic procedure begins poststernotomy and preheparin administration to mitigate bleeding risks. Supraumbilical port placement is performed for optimal direct visualization of the abdominal space for accurate driveline tunneling. It involves careful management of insufflation pressure to prevent hemodynamic collapse by restricting venous return. This approach ensures that the driveline is positioned correctly without injury to any intraabdominal structures.

Rates and predictors for sustained ventricular tachycardia in patients with cardiac sarcoidosis and AV block as first cardiac presentation: Implications for device implantation

BackgroundAtrioventricular block (AVB) is a frequent initial presentation of cardiac sarcoidosis (CS), but dangerous ventricular arrhythmias (VA) can occur. Despite the scarcity of data, guidelines recommend implantable cardioverter-defibrillator (ICD) rather than a pacemaker implantation whenever a device is needed. ObjectiveIn this study, we aimed to establish predictors for sustained VA in patients with CS presenting with pacing indication because of an AVB. MethodsWe prospectively enrolled 112 patients with CS. Excluding those with VA, 82 patients remained and were divided into 2 groups: 34 individuals with AVB as initial presentation and 48 with other symptoms as first presentation (OSF). Both groups were compared for clinical characteristics, rates of VA, left ventricular assist device (LVAD) implantation, heart transplantation, and mortality. ResultsDuring follow-up, VA was detected in 50% in the AVB and 10.4% in the OSF group (P = .001). Death, LVAD implantation, and heart transplantation occurred in 11.8% in AVB group vs 10.4% in the OSF group (P = .847). Late gadolinium enhancement (LGE) was equally observed in both groups: 70% vs 70.5% (P = .966), whereas more patients in the AVB group exhibited abnormal positron emission tomography (PET) uptake: 86.2% vs 54.3% (P = .007). In multivariate analysis, AVB (hazard ratio [HR], 25.15), right ventricular (RV) LGE in cardiovascular magnetic resonance (CMR) (HR, 7.39) were predictors for VA occurrence, whereas the use of immunosuppressive therapy was associated with less VA (HR, 0.26). ConclusionsPatients with CS presenting with AVB have a high risk of sustained VA. Although immunosuppressive drugs may reduce the occurrence of VA, ICD implantation is reasonable, especially in case of RV LGE.

326.6: Evaluation of morbidity and mortality in patients over 65 years of age with left ventricular assist device implantation.

326.6: Evaluation of morbidity and mortality in patients over 65 years of age with left ventricular assist device implantation.

Genophenotypic correlates and long-term outcome prognosticators of left ventricular non-compaction in children

BackgroundTo investigate the outcomes, clinical prognosticators, and genetic profiles of pediatric left ventricular non-compaction (LVNC). MethodsAll subjects were <18 years old, diagnosed with LVNC between January 2008 and December 2020. Whole-exome sequencing was undertaken. The primary endpoint was composite outcome, including death, heart transplant, and left ventricular assist device implantation. ResultsThirty-three patients were enrolled, males predominating (57.6%). Median age at diagnosis was 0.33 (0.1–7.2) years. Family history was documented in four (12.1%). Five (15.2%) had sustained arrhythmias. Mean follow-up period was 9.5 years, and 5- and 10-year event-free survival were 84.8% and 66.9%, respectively. Seven died of heart failure, four received heart transplants, and one required left ventricular assist device placement. Log of baseline NT-proBNP (adjusted odds ratio [aOR] = 4.4, p = 0.012) and lack of improvement in NT-proBNP (aOR = 41.2, p = 0.033) impacted the primary outcome most significantly. Eighteen out of 25 genetic testing (72%) revealed chromosomal anomalies, or pathogenic or likely pathogenic variants. Three genetic variants (PLEKHM2 p.G419R, RYR2 p.V2571A, and SCN5A p.M1676I) were significantly associated with the primary outcome (p = 1.52 × 10−6). ConclusionsPediatric LVNC is a rare disorder with variable genetic underpinnings. Baseline NT-proBNP values and lack of improvement in NT-proBNP levels were important predictors of poor long-term outcomes. Pathogenic genetic variants or chromosomal anomalies are not unusual.

Proteomic biomarkers related to obesity in heart failure with reduced ejection fraction and their associations with outcome.

Heart failure (HF) pathophysiology in patients with obesity may be distinct. To study these features, we identified obesity-related biomarkers from 4210 circulating proteins in patients with HF with reduced ejection fraction (HFrEF) and examined associations of these proteins with HF prognosis and biological mechanisms. In 373 patients with trimonthly blood sampling during a median follow-up of 2.1 (25th-75th percentile: 1.1-2.6) years, we applied an aptamer-based multiplex approach measuring 4210 proteins in baseline samples and the last two samples before study end. Associations between obesity (BMI > 30 kg/m2) and baseline protein levels were analyzed. Subsequently, associations of serially measured obesity-related proteins with biological mechanisms and the primary endpoint (PEP; composite of cardiovascular mortality, HF hospitalization, left ventricular assist device implantation, and heart transplantation) were examined. Obesity was identified in 26% (96/373) of patients. A total of 30% (112/373) experienced a PEP (with obesity: 26% [25/96] vs. without obesity: 31% [87/277]). A total of 141/4210 proteins were linked to obesity, reflecting mechanisms of neuron projection development, cell adhesion, and muscle cell migration. A total of 50/141 proteins were associated with the PEP, of which 12 proteins related to atherosclerosis or hypertrophy provided prognostic information beyond clinical characteristics, N-terminal pro-B-type natriuretic peptide, and high-sensitivity troponin T. Patients with HFrEF and obesityshow distinct proteomic profiles compared to patients with HFrEF without obesity. Obesity-related proteins are independently associated with HF outcome. These proteins carry potential to improve management of obesity-related HF and could be leads for future research.

Late Follow-up for a Randomized Trial of Surgical Treatment of Tricuspid Valve Regurgitation in Patients Undergoing Left Ventricular Assist Device Implantation

ObjectivesWe previously reported that concurrent tricuspid valve surgery (TVS) was not associated with a lower incidence of early RHF among patients undergoing durable LVAD implantation. This is a follow-up analysis to further define the clinical impact of concurrent TVS within 12-months of follow-up. MethodsPatients with moderate or severe TR on pre-operative echocardiography (n=71) were randomized to either LVAD implantation alone (No TVS, n=34) or with concurrent TVS (TVS, n=37). Randomization was stratified by pre-operative right ventricular dysfunction. Patients were followed for at least 12-months after surgery. The incidence of RHF was determined using INTERMACS criteria by an adjudication committee. Functional studies and repeat echocardiography were performed at 12-months. ResultsDemographics were similar between the two arms. At 12-months, the rate of moderate or severe RHF was 50.0% (No TVS) versus 51.4% (TVS). No patients developed RHF between 6- and 12-months following the procedure. Death from RHF was 5.4% (TVS) versus 8.8% (No TVS). At 12-months, there was no significant difference in TR severity between the two arms due to improvement in TR severity in the No TVS arm. On cardiopulmonary exercise testing at 12+ months, there was no significant difference in peak oxygen consumption. ConclusionsIn patients with significant pre-implant TR, the severity of TR improved over time in the LVAD implantation alone arm. By 12-months, there is no significant difference in TR severity between the two arms. This may account for the lack of difference in late clinical or functional parameters.

Active Left Atrial Ejection Fraction as a Non-Invasive Marker in Pulmonary Hypertension Secondary to Heart Failure

BackgroundPatients with pulmonary hypertension (PH) secondary to left heart failure (HF) exhibit a complex pathophysiological profile and poor prognosis. Left atrial function is pivotal in the progression of this disease, yet its predictive significance remains exclusive. This study aimed to explore the predictive capability of LA metrics in this population and compare them with other common predictors. MethodsIn this retrospective study, consecutive patients with PH secondary to HF who underwent cardiac magnetic resonance (CMR) imaging between December 2010 and December 2021 were enrolled. The composite endpoint was defined as all-cause death, heart-lung transplantation, or left ventricular assist device implantation. Survival analyses were performed using Kaplan–Meier curves and Cox regression analyses. ResultsA total of 174 patients with PH secondary to HF, with a mean age of 53.2 ± 14.9 years, including 90 men, were included in the final analysis. During a median follow-up of 31.9 months, 58 patients (33.3%) with PH reached the endpoints. There was a fair correlation between active left atrial ejection fraction (LAEF) and pulmonary artery wedge pressure (r = -0.397, p = 0.044). Active LAEF had a strong correlation with oxygen consumption at anaerobic threshold (r = 0.769, p < 0.001) and peak oxygen consumption (r = 0.754, p < 0.001). Active LAEF demonstrated comparable prognostic performance to other variables measured by echocardiography or CMR. After adjusting for clinical variables and left ventricular ejection fraction, active LAEF was still an independent predictor for adverse events (C-statistic: 0.784). Subgroup analysis among HF patients with preserved ejection fraction demonstrated that those with active LAEF ≤ 8.6% had a 7.05-fold higher risk of experiencing the composite endpoint compared to those with active LAEF > 8.6%. ConclusionAlthough active LAEF does not demonstrate statistical improvement in outcome discrimination compared to established metrics, it may still merit consideration for assessing disease severity and prognosis in patients with PH secondary to HF. The integration of active LAEF and HF subtypes may stratify individuals at different levels of risk.

Integration of Patient Reported Quality-of-life Data into Risk Assessment in Heart Failure

Optimal management of outpatients with heart failure (HF) requires serially updating the estimates of their risk for adverse clinical outcomes to guide treatment. Patient-reported outcomes (PROs) are becoming increasingly used in clinical care. The purpose of this study was to determine whether the inclusion of PROs can improve the risk prediction for HF hospitalization and death in ambulatory patients with HF. We included consecutive patients with HF with reduced ejection fraction (HFrEF) and HF with preserved EF (HFpEF) seen in a HF clinic between 2015 and 2019 who completed PROs as part of routine care. Cox regression with a least absolute shrinkage and selection operator regularization and gradient boosting machine analyses were used to estimate risk for a combined outcome of HF hospitalization, heart transplant, left ventricular assist device implantation, or death. The performance of the prediction models was evaluated with the time-dependent concordance index (Cτ). Among 1165 patients with HFrEF (mean age 59.1 ± 16.1, 68% male), the median follow-up was 487 days. Among 456 patients with HFpEF (mean age 64.2 ± 16.0 years, 55% male) the median follow-up was 494 days. Gradient boosting regression that included PROs had the best prediction performance - Cτ 0.73 for patients with HFrEF and 0.74 in patients with HFpEF, and showed very good stratification of risk by time to event analysis by quintile of risk. The Kansas City Cardiomyopathy Questionnaire overall summary score, visual analogue scale and Patient Reported Outcomes Measurement Information System dimensions of satisfaction with social roles and physical function had high variable importance measure in the models. PROs improve risk prediction in both HFrEF and HFpEF, independent of traditional clinical factors. Routine assessment of PROs and leveraging the comprehensive data in the electronic health record in routine clinical care could help more accurately assess risk and support the intensification of treatment in patients with HF.

Fibrin clot permeability (Ks) in patients on left ventricular assist device

Patients on left ventricular assist devices (LVAD) are prone to excessive hemostasis disturbances due to permanent contact of artificial pump surfaces with blood components. We aimed to investigate if fibrin clot permeability is altered in patients on long-term continuous-flow LVAD therapy and if the clot permeability is associated with clinical characteristics and adverse events. We investigated 85 end-stage heart failure patients (90.6% men, age 48.6–63.8 years) scheduled for continuous flow long-term LVAD support according to current clinical indications. The patients were assessed periodically: prior to LVAD implantation (T1), 3–6 months (T2) after LVAD implantation, 6–12 months after (T3) and then every 6 months. We tested the first three blood samples (T1-T3) and the last available blood sample (T4), but no longer than 5 years after LVAD implantation. We assessed hemostasis parameters (Activated Partial Thromboplastin Time (APTT) Prothrombin Time, Activated Partial Thromboplastin Time, Fibrinogen, d-dimer, Antithrombin, Thrombin Time, Factor VIII, and von Willebrand Factor, aspirin-induced platelet inhibition, adenosine-diphosphate test) changes during the study period. Fibrin Clot Permeability was evaluated using a pressure system and Permeability Coefficient (Ks) was calculated. We observed a decrease in fibrin clot permeability (Ks) between T1, T2, T3 and T4 time periods; P < 0.01 for each comparison. Fibrin clot permeability was negatively correlated with fibrinogen concentration: r = − 0.51, P < 0.001, factor VIII activity r = − 0.42, P < 0.001. There was no association of Ks with age, Left Ventricular Ejection Fraction (LVEF) and medications P > 0.001, however cumulative measurements in patients on aspirin showed shortening of Ks in this group P = 0.0123. Major adverse cardiac and cerebrovascular events (MACCE) occurred in 36.5% patients, bleeding events in 25.9%, Net Adverse Clinical Events (NACE) in 62.4%; 31.7% patients died, and 17.6% underwent transplantation. The transplantation was considered as the endpoint. Discrepancies in Ks were observed between patients with MACCE, bleeding, and NACE, and patients without adverse events. Ks showed a constant trend towards normalization (P < 0.01) only in patients without adverse events. Patients with advanced heart failure have disturbed clot structure. A trend towards normalization of the Ks values is associated with fewer thromboembolic and bleeding complications in this group of patients.

Orthotopic heart transplantation in patient with situs inversus and pectus excavatum: a case report

BackgroundHeart transplantation in patients with situs inversus is challenging, especially in terms of reconstruction of the systemic venous return. Several rerouting techniques have been presented but are associated with vulnerability to external compression, which might cause hemodynamic instability, especially in the presence of chest deformity. In this study, we report a rare case of successful heart transplantation in the presence of situs inversus and pectus excavatum.Case presentationA 55-year-old man, with a history of surgeries for corrected transposition of the great arteries with ventricular septal defect, was registered for heart transplantation owing to progression of heart failure. Subsequently, he had undergone a left ventricular assist device implantation; 14 years after registration, he underwent transplantation of the heart with normal anatomy. The inferior vena cava was reconstructed by anastomosing the left atria with a counterclockwise rotation of the donor heart and by lengthening the recipient inferior vena cava with a conduit made of the residual right atrial tissue. The superior vena cava was reconstructed using a donor innominate vein harvested with sufficient length. After successful weaning from cardiopulmonary bypass, the chest could not be closed because the heart was compressed owing to chest deformity, resulting in hemodynamic instability. Therefore, to exclude the left lung, a left pericardial screen was created using a bovine pericardium, allowing the chest to be closed with acceptable hemodynamics. The patient suffered postoperatively from a higher venous pressure, suggesting an obstruction of venous return early after surgery. The obstruction gradually resolved, and the patient was transferred for rehabilitation.ConclusionsHeart transplantation in the presence of situs inversus is challenging; moreover, the presence of pectus excavatum further complicates the procedure. The paradoxically larger left lung and chest deformity compressed and impaired reconstructed systemic venous return. Although intrathoracic exclusion of the left lung was effective, an intraoperative or early postoperative thoracoplasty for pectus excavatum was also a viable option. Patient-specific management is mandatory, depending on the anatomy.

Association between caseload volume and outcomes in left ventricular assist device implantations-a EUROMACS analysis.

This EUROMACS study was conducted with the primary aim of investigating the association between a centre's annual caseload and postoperative outcomes among patients undergoing left ventricular assist device (LVAD) implantation. A total of 4802 patients identified between 2011 and 2020 from 35 participating centres were dichotomized based on the annual caseload of the treating centre at the time of device implant (≤30 vs. >30 LVAD implantations/year). The primary endpoint was 1-year survival. Secondary outcomes included overall survival analysis, device-related adverse events and readmissions. Cumulative follow-up was 10 003 patient-years, with a median follow-up of 1.54 years (interquartile range 0.52-3.15). Patients from higher volume centres more frequently presented in INTERMACS levels 1 and 2, suffered from right heart dysfunction and needed inotropic support. No difference was observed in adjusted 1-year survival. Adjusted overall survival probability was lower in higher volume centres (p = 0.002). In the subgroup analysis of HeartMate 3 devices only, higher volume centres were associated with decreased odds of 1-year survival (adjusted odds ratio 0.43, 95% confidence interval 0.20-0.97, p = 0.041). Similar findings were observed in the cumulative (i.e. learning curve) caseload analyses. In patients undergoing LVAD implantation, centre volume was not associated with 1-year survival, but was related to device-related adverse events. Patient profiles differed with respect to centre size. These findings underscore the necessity for ongoing quality improvement initiatives in all centres, regardless of their annual caseload. Efforts are needed to standardize patient selection and preconditioning to further improve patient outcome.

Stereotactic Ablative Radiotherapy for Early-stage Lung Cancer in Patients With Left Ventricular Assist Device: A Case Series.

Radiotherapy-induced malfunction of pacemakers and cardiac defibrillators has been reported, and corresponding guidelines have been developed in various countries. Although several studies have reported the effects of radiotherapy in patients with implantable left ventricular assist device (LVAD), its safety remains unclear. Herein, we report three cases of stereotactic ablative radiotherapy (SABR) using CyberKnife for early-stage lung cancer in patients with implantable LVAD. Three patients in their 50s or 60s, including two women and one man, who had LVADs due to dilated or ischemic cardiomyopathy and performance status of 0 or 1, were diagnosed with stage IA2 lung cancer (cT1bN0M0) by imaging only. All three patients were deemed inoperable due to cardiac comorbidity and underwent SABR at the Osaka University Hospital. The total radiation dose was 42-52 Gy, administered in four fractions. All treatment plans were designed to keep the LVAD dose below 2 Gy. In all patients, SABR was completed without acute adverse events or LVAD malfunction. During the follow-up period of 3-29 months, no disease progression or chronic adverse events were observed in any of the patients. This case series indicated that SABR using CyberKnife is a safe treatment option for early-stage lung cancer in patients with LVAD by reducing the dose to the LVAD.

Development of a hub-and-spoke durable left ventricular assist device program in Brazil, a middle-income country

ObjectivesTo describe the experience of a left ventricular assist device (LVAD) program in a middle-income country in a hub-and-spoke model. MethodsPatients fulfilling strict inclusion and exclusion criteria were referred from different centers in Brazil for LVAD implantation through a philanthropy program financed via a Brazilian Federal Government tax exemption structure. LVAD implantation was performed in hub-and-spoke model with a single implanting center. Data was collected retrospectively using hospital records and telephone contact with other centers. Patients that received LVAD implants external to the philanthropic program, either at this or other Brazilian centers, were not included. ResultsBetween January 1st, 2013, and December 31st, 2020, 20 adult patients underwent long-term continuous flow LVAD implantation with decentralization of post-implant patient care in regional centers. Patients were referred from 11 centers from 7 states in Brazil and underwent LVAD implantation through a philanthropy program. The median age was 52.5 years and 85% were INTERMACS profile 3 patients. Two patients had Chagas cardiomyopathy. The overall survival censored for competing risks at 1 year and 2 years were 90% and 84% respectively. Three patients (15%) underwent heart transplantation in the first 2 years after LVAD implantation. Twelve patients returned to their original centers and were followed remotely. ConclusionsThis study presents a successful LVAD implantation program in a hub-and-spoke model in Brazil. Centralization of LVAD implantation with decentralization of post-implant patient care in regional centers is feasible and safe, enabling optimal allocation of resources in middle-income countries.

Serum Uric Acid as an Indicator of Right Ventricular Dysfunction in LVAD Patients: A Preliminary Study.

(1) Background: Left ventricular assist devices (LVADs) represent mechanical support in end-stage congestive heart failure and are characterized by satisfactory long-term results. Uric acid (UA) represents one of the early heart failure markers whose usefulness was postulated in clinical practice. (2) Methods: Twenty-nine male patients with a median age of 58 (51-62) years were referred for LVAD implantation due to end-stage congestive heart failure in the mean (SD) New York Heart Association (NYHA) status class 3.3 (0.6). Preoperative and postoperative right ventricular (RV) characteristics were compared with serum uric acid concentration within 12 (8-15) months following the implantation. (3) Results: Significant correlations between postoperative uric acid concentration and right ventricular dimension (r = 0.604, p = 0.005), tricuspid annulus plane systolic excursion (TAPSE) (r = -0.496, p = 0.022), left ventricular ejection fraction (r = -0.463, p = 0.046), and N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) (r = 0.505, p = 0.041) were noted. (4) Conclusions: The analysis shows the association between the postoperative RV diameter and TAPSE results in LVAD patients and uric acid concentration. Serum uric acid can be regarded as a possible right ventricular dysfunction marker in LVAD patients.

Effect of Preoperative Mitral Regurgitation on LVAD Outcomes in Patients with Elevated Pulmonary Vascular Resistance.

In patients with end-stage heart failure who undergo left ventricular assist device (LVAD) implantation, higher pulmonary vascular resistance (PVR) is associated with higher right heart failure rates and ineligibility for heart transplant. Concomitant mitral regurgitation (MR) could potentially worsen pulmonary hemodynamics and lead to worse outcomes; however, its effects in this patient population have not been specifically examined. Using an institutional database spanning November 2003 to August 2017, we retrospectively identified patients with elevated PVR who underwent LVAD implantation. Patients were stratified by concurrent MR: moderate/severe (PVR + MR) vs. mild/none (PVR - MR). Cumulative incidence functions and Fine-Gray competing risk regression were performed to assess the effect of MR on heart transplant rates and overall survival during index LVAD support. Of 644 LVAD recipients, 232 (171 HeartMate II, 59 HeartWare, 2 HeartMate III) had baseline PVR > 3 Woods units; of these, 124 (53%) were INTERMACS 1-2, and 133 (57%) had moderate/severe MR (≥ 3 +). Patients with PVR + MR had larger a baseline left ventricular end-diastolic diameter than patients with PVR - MR (87.9 ± 38.2 mm vs. 75.9 ± 38.0 mm; P = 0.02). Median clinical follow-up was 18.8 months (interquartile range: 4.7-36.4 months). Moderate/severe MR was associated with lower mortality rates during index LVAD support (adjusted hazard ratio 0.64, 95% CI 0.41-0.98; P = 0.045) and higher heart transplant rates (adjusted odds ratio 2.86, 95% CI 1.31-6.25; P = 0.009). No differences in stroke, gastrointestinal bleeding, or right heart failure rates were observed. Among LVAD recipients with elevated preoperative PVR, those with moderate/severe MR had better overall survival and higher transplant rates than those with mild/no MR. These hypothesis-generating findings could be explained by incremental LVAD benefits resulting from reduction of MR and better LV unloading in a subset of patients with larger ventricles at baseline. In patients with preoperative elevated PVR, MR severity may be a prognostic sign that can inform patient selection for end-stage heart failure therapy.

In Vivo Testing of a Second-Generation Prototype Accessory for Single Transapical Left Ventricular Assist Device Implantation.

A new accessory was developed to allow implantation of left ventricular assist devices (LVADs) without requiring an anastomosis to the ascending aorta. The accessory combines the LVAD inflow and outflow into a dual-lumen device. Initial prototypes encountered reduced pump performance in vitro, but a second-generation prototype successfully addressed this issue. This feasibility study aimed to demonstrate the anatomic fit, safe implantation, and hemodynamic effectiveness of the LVAD with the accessory. The accessory was implanted in ten female pigs (104 ± 13 kg). Following sternotomy and apical coring under cardiopulmonary bypass, a balloon catheter was retrogradely inserted and exteriorized through the coring site, where it was inflated within the distal third of the outflow graft. It was utilized to pull the accessory's outflow across the aortic valve. After LVAD attachment, the catheter was removed. Echocardiography revealed no relevant valve regurgitation post-implantation. During ramp testing, pump flow increased from 3.7 ± 1.2 to 5.4 ± 1.2 L/min. Necropsy confirmed correct accessory placement in nine animals. No valve lesions or device thrombosis were observed. The accessory enabled LVAD implantation without compromising pump performance. Future work includes design refinements for implantation without cardiopulmonary bypass and long-term testing in a chronic heart failure model.

Escalating Surgical Treatment for Left Ventricular Assist Device Infection and Expected Mortality: Clinical Risk Prediction Score.

Left ventricular assist devices (LVAD) improve survival for patients with cardiac failure, but LVAD-specific infection (VSI) remains a challenge with poorly understood predictive risk factors. The indications and use of escalating medical treatment to surgical debridement and potential flap reconstruction are not well characterized. A retrospective review of consecutive patients undergoing primary LVAD implantation at a tertiary academic center was performed. The primary outcome measures were 90-day and overall mortality after VSI. Cox proportional hazards regression was used to generate a risk prediction score for mortality. Of the 760 patients undergoing primary LVAD implantation, 255 (34%) developed VSI; of these patients, 91 (36%) were managed medically, 134 (52%) with surgical debridement, and 30 (12%) with surgical debridement and flap reconstruction. One-year survival after infection was 85% with median survival of 2.40 years. Factors independently associated with increased mortality were diabetes (hazard ratio [HR] 1.44, p = 0.04), MRSA infection (HR 1.64, p = 0.03), deep space (pump pocket or outflow cannula) involvement (HR 2.26, p < 0.001), and extracorporeal membrane oxygenation after LVAD (HR 2.52, p < 0.01). Factors independently associated with decreased mortality were flap reconstruction (HR 0.49, p = 0.02) and methicillin-sensitive Staphylococcus aureus infection (HR 0.63, p = 0.03). A clinical risk prediction score was developed using these factors and showed significant differences in median survival, which was 5.67 years for low-risk (score 0 to 1), 3.62 years for intermediate-risk (score 2), and 1.48 years for high-risk (score ≥3; p < 0.001) patients. We developed a clinical risk prediction score to stratify patients with VSI. In selected cases, escalating surgical treatment was associated with increased survival. Future work is needed to determine whether early surgical debridement and flap reconstruction can alter outcomes in select cases of VSI.