Usefulness of the INTERMACS Scale to Predict Outcomes After Mechanical Assist Device Implantation

Impact of center volume on outcomes after ventricular assist device implantation in pediatric patients: An analysis of the STS-Pedimacs database

BACKGROUND

To date, no pediatric studies have highlighted the impact of center's ventricular assist device (VAD) volumes on post implant outcomes.

METHODS

Children (age <19) enrolled in Pedimacs undergoing initial left ventricular assist device implantation from 2012 to 2020 were included. Center volume was analyzed as a continuous and categorical variable. For categorical analysis, center volumes were divided as: low volume (1-15 implants), medium volume (15-30 implants), and high volume (>30 implants) during our study period. Patient characteristics and outcomes were compared by center's VAD volumes.

RESULTS

Of 44 centers, 16 (36.4%) were low, 11 (25%) were medium, and 17 (38.6%) were high-volume centers. Children at high-volume centers were least likely intubated, sedated, or paralyzed, and most likely ambulating preimplant (p < 0.05 for all). Center's VAD volumes were not a significant risk factor for mortality post implant when treated as a continuous or a categorical variable (p > 0.05). Compared to low volume, children at high-volume centers had fewer early neurological events. Compared to medium volume, those at high-volume centers had fewer late bleeding events (p < 0.05 for all). There were no significant differences in survival after an adverse event by hospital volumes (p > 0.05).

CONCLUSIONS

Although hospital volume does not affect post-VAD implant mortality, pediatric centers with higher VAD volumes have fewer patients intubated, sedated, paralyzed pre implant, and have lower adverse events. Failure to rescue was not significantly different between low, medium, and high-volume VAD centers.

Advanced Heart Failure: Therapeutic Options and Challenges in the Evolving Field of Left Ventricular Assist Devices

Heart Failure is a chronic and progressively deteriorating syndrome that has reached epidemic proportions worldwide. Improved outcomes have been achieved with novel drugs and devices. However, the number of patients refractory to conventional medical therapy is growing. These advanced heart failure patients suffer from severe symptoms and frequent hospitalizations and have a dismal prognosis, with a significant socioeconomic burden in health care systems. Patients in this group may be eligible for advanced heart failure therapies, including heart transplantation and chronic mechanical circulatory support with left ventricular assist devices (LVADs). Heart transplantation remains the treatment of choice for eligible candidates, but the number of transplants worldwide has reached a plateau and is limited by the shortage of donor organs and prolonged wait times. Therefore, LVADs have emerged as an effective and durable form of therapy, and they are currently being used as a bridge to heart transplant, destination lifetime therapy, and cardiac recovery in selected patients. Although this field is evolving rapidly, LVADs are not free of complications, making appropriate patient selection and management by experienced centers imperative for successful therapy. Here, we review current LVAD technology, indications for durable MCS therapy, and strategies for timely referral to advanced heart failure centers before irreversible end-organ abnormalities.

Pharmacological Considerations during Percutaneous Treatment of Heart Failure

Heart Failure (HF) remains a global health challenge, marked by its widespread prevalence and substantial resource utilization. Although the prognosis has improved in recent decades due to the treatments implemented, it continues to generate high morbidity and mortality in the medium to long term. Interventional cardiology has emerged as a crucial player in HF management, offering a diverse array of percutaneous treatments for both acute and chronic HF. This article aimed to provide a comprehensive review of the role of percutaneous interventions in HF patients, with a primary focus on key features, clinical effectiveness, and safety outcomes. Despite the growing utilization of these interventions, there remain critical gaps in the existing body of evidence. Consequently, the need for high-quality randomized clinical trials and extensive international registries is emphasized to shed light on the specific patient populations and clinical scenarios that stand to benefit most from these innovative devices.

Novel Risk Stratification and Hemodynamic Profiling in Acute Pulmonary Embolism: A Proposed Classification Inspired by Society for Cardiovascular Angiography and Intervention Shock Staging

Treatment options for patients with acute pulmonary embolism (PE) and right ventricular shock (RVS) have grown exponentially. Therapy options include anticoagulation, systemic thrombolysis, catheter-based thrombolysis/ thrombectomy, and may include short-term mechanical circulatory support. However, the incidence of short-term morbidity and mortality has not changed despite the emergence of several advanced therapies in acute PE. This is possibly due to the inclusion of heterogenous populations in research studies without differentiation based on the acuity/severity of presentation. We propose a novel classification for PE-RVS to allow for standardizing appropriate therapy escalation and better communication of the severity among cardiovascular critical care, and emergency health care professionals.

Advanced heart failure: a contemporary approach

Advanced heart failure (HF) is defined as the persistence of severe symptoms despite the use of optimized medical, surgical, and device therapies. These patients require timely advanced treatments, such as heart transplantation or long-term mechanical circulatory support (MCS). Inotropic agents are often used to reduce congestion and increase cardiac output, while renal replacement therapy may be beneficial if necessary. Cardiac resynchronization therapy has clear benefits in patients with HF with reduced ejection fraction, particularly with left bundle branch block (QRS duration > 130 ms). The role of implantable cardioverter-defibrillators in advanced HF patients requires further investigation considering the introduction of novel HF medications. In selected patients with significant secondary mitral regurgitation, transcatheter edge-to-edge repair can help delay heart transplantation or long-term MCS. In later stages, the appropriateness of heart transplantation should be evaluated, and the use of short- or long-term MCS may be considered. A multidisciplinary HF management program is crucial for patients with advanced HF. Recent treatment advances, including drugs, devices, and MCS, have broadened the options available to patients with advanced HF and this trend is expected to continue.

Impact of preoperative Impella support on destination left ventricular assist device outcomes

BACKGROUND

Although left ventricular assist device (LVAD) implantation is associated with improved heart failure survival, the impact of pre-implantation Impella support on outcomes is unknown. We undertook this study to evaluate the impact of preoperative Impella support on LVAD outcomes.

METHODS

We conducted a retrospective review of all Heartmate 3 LVAD implants. Primary stratification was by the need for preoperative Impella support with the 5.0/5.5 device. Longitudinal survival was assessed by the Kaplan-Meier method. Multivariable Cox proportional hazards regression models were developed to evaluate mortality. Secondary outcomes included changes in laboratory values during Impella support.

RESULTS

From 2017 to 2021, 87 patients underwent LVAD implantation. Sixteen were supported with a single inotrope, 36 with dual inotropes, 27 with Impella, and 3 with extracorporeal membrane oxygenation (ECMO). When stratified by the need for Impella, there was no difference in survival at 30-days (98.3 [88.2-99.8]% vs. 96.3 [76.5-99.5]%, p = .59), 1-year (91.0 [79.8-96.2] vs. 74.9 [51.7-88.2], p = .10), or at 2 years (87.9 [74.3-94.5] vs. 74.9 [51.7-88.2], p = .15). On multivariable modeling, the need for preoperative Impella was not associated with an increased hazard of 1-year (1.24 [0.23-6.73], p = .81) or 2-year mortality (1.05 [0.21-5.19], p = .95). After 7 (5-10) days of Impella support, recipient creatinine (p < .01), creatinine clearance (p = .02), and total bilirubin (p = .053) improved and lactic acidosis resolved (p < .01).

CONCLUSIONS

Preoperative Impella support is not associated with increased short or long-term mortality but is associated with improved renal and hepatic function as well as total body perfusion before LVAD implantation.

Left Ventricular Assist Devices: A Primer for the Non-Mechanical Circulatory Support Provider

Survival after implant of a left ventricular assist device (LVAD) continues to improve for patients with end-stage heart failure. Meanwhile, more patients are implanted with a destination therapy, rather than bridge-to-transplant, indication, meaning the population of patients living long-term on LVADs will continue to grow. Non-LVAD healthcare providers will encounter such patients in their scope of practice, and familiarity and comfort with the physiology and operation of these devices and common problems is essential. This review article describes the history, development, and operation of the modern LVAD. Common LVAD-related complications such as bleeding, infection, stroke, and right heart failure are reviewed and an approach to the patient with an LVAD is suggested. Nominal operating parameters and device response to various physiologic conditions, including hypo- and hypervolemia, hypertension, and device failure, are reviewed.

Extracorporeal membrane oxygenation as a bridge to durable left ventricular assist device implantation in INTERMACS-1 patients

Left ventricular assist devices (LVADs) are increasingly used as destination therapy or as a bridge to future cardiac transplant in patients with end-stage heart failure. Extracorporeal membrane oxygenation (ECMO) can be used to bridge patients in cardiogenic shock or with decompensated heart failure to durable mechanical circulatory support. We assessed outcomes in patients in critical cardiogenic shock (Interagency Registry for Mechanically Assisted Circulatory Support [INTERMACS] profile 1) who underwent implantation of a continuous-flow (CF)-LVAD, with or without preoperative ECMO bridging. For this retrospective study, we selected INTERMACS profile 1 patients who underwent CF-LVAD implantation at our institution between Sep 1, 2004 and Nov 30, 2018. Of 768 patients identified, 133 (17.3%) were INTERMACS profile 1; 26 (19.5%) received preoperative ECMO support, and 107 (80.5%) did not. Postimplantation outcomes were compared between the ECMO and no-ECMO groups. No significant differences were found in 30-day mortality (15.4 vs. 15.9%, P = 0.95) or survival at 1 year (53.8 vs. 60.9%, P = 0.51). Three patients who received ECMO before CF-LVAD implantation subsequently underwent cardiac transplant. In the ECMO group, the lactate level 1 day after ECMO initiation was lower in survivors than nonsurvivors (2.7 ± 2.2 vs. 7.4 ± 4.2 mmol/L, P = 0.02; area under the curve = 0.85, P = 0.01) after CF-LVAD implantation. Bridging with ECMO to CF-LVAD implantation in carefully selected INTERMACS profile 1 patients (those who are at the highest risk for critical cardiogenic shock and for whom palliation may be the only other option) produced acceptable postoperative outcomes.Field of research: Artificial lung/ECMO.

Dynamic Assessment of Pulmonary Artery Pulsatility Index Provides Incremental Risk Assessment for Early Right Ventricular Failure After Left Ventricular Assist Device

BACKGROUND

The pulmonary artery pulsatility index (PAPi) has been studied to predict right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation, but only as a single time point before LVAD implantation. Multiple clinical factors and therapies impact RV function in pre-LVAD patients. Thus, we hypothesized that serial PAPi measurements during cardiac intensive care unit (CICU) optimization before LVAD implantation would provide incremental risk stratification for early RVF after LVAD implantation.

METHODS AND RESULTS

Consecutive patients who underwent sequential pulmonary artery catherization with cardiac intensive care optimization before durable LVAD implantation were included. Serial hemodynamics were reviewed retrospectively across the optimization period. The optimal PAPi was defined by the initial PAPi + the PAPi at optimized hemodynamics. RVF was defined as need for a right ventricular assist device or prolonged inotrope use (>14 days postoperatively). Patients with early RVF had significantly lower mean optimal PAPi (3.5 vs 7.5, P < .001) compared with those who did not develop RVF. After adjusting for established risk factors of early RVF after LVAD implantation, the optimal PAPi was independently and incrementally associated with early RVF after LVAD implantation (odds ratio 0.64, 95% confidence interval 0.532-0.765, P < .0001).

CONCLUSIONS

Optimal PAPi achieved during medical optimization before LVAD implantation provides independent and incremental risk stratification for early RVF, likely identifying dynamic RV reserve.

Comparison among different multiparametric scores for risk stratification in heart failure patients with reduced ejection fraction

Heart failure is a serious condition with high prevalence (about 2% in the adult population in developed countries, and more than 8% in patients older than 75 years). About 3–5% of hospital admissions are linked with heart failure incidents. The guidelines of the European Society of Cardiology for the diagnosis and treatment of acute and chronic heart failure have identified individual markers in patients with heart failure, including demographic data, aetiology, comorbidities, clinical, radiological, haemodynamic, echocardiographic and biochemical parameters. Several scoring systems have been proposed to identify adverse events, such as destabilizations, re-hospitalizations and mortality. This article reviews scoring systems for heart failure prognostication, with particular mention of those models with exercise tolerance objective definition. Although most of the models include readily available clinical information, quite a few of them comprise circulating levels of natriuretic peptides and a more objective evaluation of exercise tolerance. A literature review was also conducted to (a) identify heart failure risk-prediction models, (b) assess statistical approach, and (c) identify common variables.

Current perspectives on mechanical circulatory support

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

A review of the management of patients with advanced heart failure in the intensive care unit

Despite progress in the medical and device therapy for heart failure (HF), the prognosis for those with advanced HF remains poor. Acute heart failure (AcHF) is the rapid development of, or worsening of symptoms and signs of HF typically leading to hospitalization. Whilst many HF decompensations are managed at a ward-based level, a proportion of patients require higher acuity care in the intensive care unit (ICU). Admission to ICU is associated with a higher risk of in-hospital mortality, and in those who fail to respond to standard supportive and medical therapy, a proportion maybe suitable for mechanical circulatory support (MCS). The optimal pre-operative management of advanced HF patients awaiting durable MCS or cardiac transplantation (CTx) is vital in improving both short and longer-term outcomes. This review will summarize the clinical assessment, hemodynamic profiling and management of the patient with AcHF in the ICU. The general principles of pre-surgical optimization encompassing individual systems (the kidneys, the liver, blood and glycemic control) will be discussed. Other factors impacting upon post-operative outcomes including nutrition and sarcopenia and pre-surgical skin decolonization have been included. Issues specific to durable MCS including the assessment of the right ventricle and strategies for optimization will also be discussed.

Utility of the INTERMACS profile at the time of assessment for heart transplant

The Interagency Registry of Mechanically Assisted Circulatory Support (INTERMACS) profiles are associated with mortality in heart failure patients undergoing ventricular assist device (VAD) implantation and heart transplantation (HTx). We assessed the prognostic value of the INTERMACS profile at the time of assessment for HTx or durable VAD implantation as bridge to candidacy (BTC). A total of 503 consecutive patients considered for HTx or VAD between 2006 and 2016 were included. The associations between INTERMACS profile and (a) waitlist mortality or delisting, (b) probability of HTx, and (c) overall mortality or delisting were evaluated using multivariable analysis. Median follow-up time was 2.9 years (IQR: 0.9-5.5) during which 184 received VAD, 347 received HTx, and 73 died (27 waitlist, 46 post-transplant). INTERMACS I-II profile was associated with higher waitlist mortality or delisting (HR: 3.83, 95% CI: 1.22-12.03), and this risk was reversed by VAD implantation (HR: 0.12, 95% CI: 0.03-0.50). INTERMACS III-IV profile was associated with a higher probability of HTx (HR: 1.82, 95% CI: 1.37-2.40). INTERMACS profile was not associated with the composite outcome of overall mortality or delisting. These results emphasize the prognostic utility of INTERMACS at time of decision for advanced therapies and its potential value in selecting patients for different interventions.

Causes and predictors of early mortality in patients treated with left ventricular assist device implantation in the European Registry of Mechanical Circulatory Support (EUROMACS)

PURPOSE

The aim of the study was to analyze early mortality after continuous-flow left ventricular assist device (LVAD) implantation which remains high.

METHODS

We analyzed consecutive (n = 2689) patients from the European Registry for Patients with Mechanical Circulatory Support (EUROMACS) undergoing continuous-flow LVAD implantation. The primary outcome was early (< 90 days) mortality. Secondary outcomes were differential causes of early post-operative death following LVAD implantation.

RESULTS

Univariable and multivariable analysis as well as regression analysis were used to examine determinants and differential causes of early (< 90 days) mortality after LVAD implantation. During the first 90 days, 2160 (80%) patients were alive with ongoing LVAD support, 40(2%) patients underwent heart transplantation, and 487(18%) deceased. The main causes of early death were MOF (36%), sepsis (28%), cardiopulmonary failure (CPF; 10%), CVA (9%), and right-sided heart failure (RHF, 8%). Furthermore, MOF and sepsis are 70% of causes of death in the first week. Independent clinical predictors of early death were age, female sex, INTERMACS profile 1 to 3, and ECMO. Laboratory predictors included elevated serum creatinine, total bilirubin, lactate, and low hemoglobin. Furthermore, hemodynamic predictors included elevated RA-to-PCWP ratio, pulmonary vascular resistance, and low systemic vascular resistance. Longer total implantation time was also independent predictor of early mortality. A simple model of 12 variables predicts early mortality following LVAD implantation with a good discriminative power with area under the curve of 0.75.

CONCLUSIONS

In the EUROMACS registry, approximately one out of five patients die within 90 days after LVAD implantation. Early mortality is primarily dominated by multiorgan failure followed by sepsis. A simple model identifies important parameters which are associated with early mortality following LVAD implantation.

Improving risk prediction in heart failure using machine learning

BACKGROUND

Predicting mortality is important in patients with heart failure (HF). However, current strategies for predicting risk are only modestly successful, likely because they are derived from statistical analysis methods that fail to capture prognostic information in large data sets containing multi-dimensional interactions.

METHODS AND RESULTS

We used a machine learning algorithm to capture correlations between patient characteristics and mortality. A model was built by training a boosted decision tree algorithm to relate a subset of the patient data with a very high or very low mortality risk in a cohort of 5822 hospitalized and ambulatory patients with HF. From this model we derived a risk score that accurately discriminated between low and high-risk of death by identifying eight variables (diastolic blood pressure, creatinine, blood urea nitrogen, haemoglobin, white blood cell count, platelets, albumin, and red blood cell distribution width). This risk score had an area under the curve (AUC) of 0.88 and was predictive across the full spectrum of risk. External validation in two separate HF populations gave AUCs of 0.84 and 0.81, which were superior to those obtained with two available risk scores in these same populations.

CONCLUSIONS

Using machine learning and readily available variables, we generated and validated a mortality risk score in patients with HF that was more accurate than other risk scores to which it was compared. These results support the use of this machine learning approach for the evaluation of patients with HF and in other settings where predicting risk has been challenging.

[Mechanical circulatory support in terminal heart failure]

BACKGROUND

After exhaustion of all conservative measures in the treatment of acute and chronic heart insufficiency, there is the possibility to temporarily or permanently support or replace the pump performance of the heart by mechanical circulatory support (MCS) systems.

OBJECTIVE

Presentation of the most important cardiac support systems for intensive care medicine, their indications and important risk factors.

MATERIAL AND METHODS

Critical review of device manufacturer's specifications, current research and expert opinions.

RESULTS

The spectrum of available MCS procedures include mechanical chest compression devices, catheter-based micropumps and complete artificial hearts. Device selection depends on the severity of heart failure (monoventricular or biventricular pump failure), the expected duration of treatment and the degree of lung function impairment. The decision between minimally invasive and open surgical procedures depends on the options established at the specific healthcare institution and whether the heart function is to be temporarily or permanently replaced. Compliance with the anticoagulation regimens defined by the manufacturer is especially important as they differ vastly between devices and are critical to avoid bleeding or thromboembolic complications.

CONCLUSION

Due to the increasing number of patients on long-term mechanical circulatory support, the chances are that physicians in the initial emergency admission are unfamiliar with these devices but need to operate them in emergency cases. Therefore, knowledge of these procedures and their complications becomes increasingly important.

Continuously Updated Estimation of Heart Transplant Waitlist Mortality

BACKGROUND

Heart transplant allocation in the United States is made on the basis of coarse tiers, defined by mechanical circulatory devices and therapy for advanced heart failure, updated infrequently as a patient's condition deteriorates. Thus, many patients die awaiting heart transplantation. What is needed is a tool that continuously updates risk of mortality as a patient's condition changes to inform clinical decision making.

OBJECTIVES

This study sought to develop a decision aid that aggregates adverse events and measures of end-organ function into a continuously updated waitlist mortality estimate.

METHODS

From 2008 to 2013, 414 patients were listed for heart transplantation at Cleveland Clinic, Cleveland, Ohio. The endpoint was waitlist death. Pre-listing patient characteristics and events and laboratory results during listing were analyzed. At each event or measurement change, mortality was recomputed from the resulting model.

RESULTS

There were 77 waitlist deaths, with 1- and 4-year survival of 85% and 57%, respectively. When time-varying events and measurements were incorporated into a mortality model, pre-listing patient characteristics became nonsignificant. Neurological events (hazard ratio [HR]: 13.5; 95% confidence interval [CI]: 7.63 to 23.8), new requirement for dialysis (HR: 3.67; 95% CI: 1.88 to 7.14), more respiratory complications (HR: 1.79 per episode; 95% CI: 1.23 to 2.59), and higher serum bilirubin (p < 0.0001) and creatinine (p < 0.0001) yielded continuously updated estimates of patient-specific mortality across the waitlist period.

CONCLUSIONS

Mortality risk for patients with advanced heart failure who are listed for transplantation is related to adverse events and end-organ dysfunction that change over time. A continuously updated mortality estimate, combined with clinical evaluation, may inform status changes that could reduce mortality on the heart transplant waiting list.

Left ventricular assist device as destination therapy for end stage heart failure: the right time for the right patients

PURPOSE OF REVIEW

Cardiac transplantation is the gold standard treatment for patients with end-stage heart failure. Unfortunately, the demand for donor organs far outstrips the number of available hearts. Therefore, not all patients who can benefit from this therapy are even listed for transplant. Once destination therapy was approved for the long-term support of nontransplant eligible patients, it was felt that the number of durable ventricular assist device (VAD) implants would increase. It was not until the current generation continuous-flow VADs became available that the number of DT-VAD implants grew significantly. The purpose of this manuscript is to review current indications and outcomes following durable VAD implant for destination therapy.

RECENT FINDINGS

In 2014, DT-VADs accounted for 46% of all implants. A propensity-matched analysis showed that 1-year and 2-year survival rates were similar between LVADs and cardiac transplantation. Likely because of their younger age and lack of comorbidities, survival after VAD implant in transplant eligible patients remains higher than after DT-VAD implant. However, the survival differences are narrowing. Although the rates of LVAD-related adverse events continue to be high, studies such as the PREVENT trial have proven that strict adherence to management protocols can reduce event rates.

SUMMARY

Improvements in device technology as well as patient selection and management have led to improved medium term (2-4 years) survival after VAD implant in nontransplant eligible patients. We anticipate that this technology will soon be a reasonable and competitive alternative to conventional heart transplantation.

Impact of preoperative extracorporeal life support on left ventricular assist device outcomes: A comparative study

Background:

To investigate whether preoperative short-term extracorporeal life support therapy in patients undergoing continuous-flow left ventricular assist device implantation has an impact on the outcome regarding survival and adverse events.

Methods:

Between January 2011 and May 2018, 100 consecutive patients received HeartMate II, HeartWare, or HeartMate III for end-stage heart failure. Mean age was 64.2 ± 10.3 years. Three patient groups were identified: without preoperative extracorporeal life support (non-extracorporeal life support group, n = 80), with preoperative extracorporeal life support due to postcardiotomy shock after conventional cardiac surgery (postcardiotomy shock group, n = 9), and with preoperative extracorporeal life support without previous surgery (non-postcardiotomy shock group, n = 11). The primary endpoint was overall survival after device implantation. Secondary endpoints were adverse events during the follow-up period.

Results:

Survival was significantly different between the groups (p < 0.05): 30-day, 6-month, and 1-year survival rates were 85%, 68%, and 61% for non-extracorporeal life support group; 44%, 22%, and 22% for postcardiotomy shock group; and 45%, 27%, and 24% for non-postcardiotomy shock group, respectively. Furthermore, in both extracorporeal life support groups (postcardiotomy shock and non-postcardiotomy shock), there were a higher incidence (p < 0.05) of postoperative right heart failure (30% vs 66.7% vs 54.5%), acute renal failure requiring dialysis (20% vs 77.8% vs 54.5%), and respiratory failure (31.3% vs 88.9% vs 81.8%).

Conclusion:

Continuous-flow left ventricular assist device implantation with prior extracorporeal life support appears to have a worse outcome regarding survival, right heart failure, renal and respiratory dysfunction (p < 0.05). Future studies have to be done to evaluate the outcome after extracorporeal life support bridge pre-left ventricular assist device, especially as ultima ratio in postcardiotomy shock patients.

Definitions of Stage D heart failure and outcomes among outpatients with heart failure and reduced ejection fraction

BACKGROUND

An operational consensus definition of Stage D heart failure (HF) is currently lacking.

METHODS

We evaluated 512 outpatients (median age, 63 years; 35.0% women; 45.5% white and 45.9% black; median ejection fraction was 25%; 67.4% had coronary artery disease) with HF and reduced (≤40%) ejection fraction. We applied 3 hypothetical definitions for Stage D: (1) designation as "Stage D" or "advanced" HF by treating physician; (2) INTERMACS profiles, defining Stage D as profiles 2-6; and (3) European Society of Cardiology Heart Failure Association (ESC-HFA) criteria.

RESULTS

Physicians, INTERMACS profiles, and ESC-HFA criteria identified 64 (12.5%), 93 (18.2%), and 67 (13.1%) patients, respectively, as Stage D, with modest concordance between definitions (κ = 0.37). After a median of 3.1 years, 97 patients died (3-year mortality 20.4%). Among patients identified as Stage D by physicians, 3-year mortality was 43.7% vs. 17.0% for non-Stage D patients (age-adjusted hazard ratio [HR] 3.17; 95%CI 1.94-5.18; P < 0.001). The corresponding mortalities for the INTERMACS-based definition were 41.0% vs. 16.2% (HR 3.28; 95%CI 2.11-5.11; P < 0.001) and for ESC-HFA criteria 33.5% vs. 18.6% (HR 2.02; 95%CI 1.22-3.33; P = 0.006); the INTERMACS-based definition provided the best prognostic separation. Results were similar with an alternative INTERMACS-based definition considering only profiles 2-5 as Stage D HF. The INTERMACS-based definition best separated all-cause and HF-specific hospitalization and composite endpoint risk between Stage D and non-Stage D patients also.

CONCLUSIONS

INTERMACS profiles provide a practical alternative for the identification of Stage D HF in ambulatory populations with systolic HF. The ESC-HFA criteria offer limited prognostic information.

INTERMACS Profiles and Outcomes Among Non-Inotrope-Dependent Outpatients With Heart Failure and Reduced Ejection Fraction

OBJECTIVES

This study sought to evaluate INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profiles for prognostic use among ambulatory non-inotrope-dependent patients with heart failure with reduced ejection fraction (HFrEF).

BACKGROUND

Data for INTERMACS profiles and prognoses in ambulatory patients with HFrEF are limited.

METHODS

We evaluated 3-year outcomes in 969 non-inotrope-dependent outpatients with HFrEF (EF: ≤40%) not previously receiving advanced HF therapies. Patients meeting an INTERMACS profile at baseline were classified as profile 7 (n = 348 [34.7%]); 146 patients (14.5%) were classified profile 6; and 52 patients (5.2%) were classified profile 4 to 5. Remaining patients were classified "stable Stage C" (n = 423 [42.1%]).

RESULTS

Three-year mortality rate was 10.0% among stable Stage C patients compared with 21.8% among INTERMACS profile 7 (hazard ratio [HR] vs. Stage C: 2.45; 95% confidence interval [CI]: 1.64 to 3.66), 26.0% among profile 6 (HR: 3.93; 95% CI: 1.64 to 3.66), and 43.8% among profile 4 to 5 (HR: 6.35; 95% CI: 3.51 to 11.5) patients. Hospitalization rates for HF were 4-fold higher among INTERMACS profile 7 (38 per 100 patient-years; rate ratio [RR] vs. Stage C: 3.88; 95% CI: 2.70 to 5.35), 6-fold higher among profile 6 patients (54 per 100 patient-years; RR: 5.69; 95% CI: 3.72 to 8.71), and 10-fold higher among profile 4 to 5 patients (69 per 100 patient-years; RR: 9.96; 95% CI: 5.15 to 19.3) than stable Stage C patients (11 per 100 patient-years). All-cause hospitalization rates had similar trends. INTERMACS profiles offered better prognostic separation than NYHA functional classifications.

CONCLUSIONS

INTERMACS profiles strongly predict subsequent mortality and hospitalization burden in non-inotrope-dependent outpatients with HFrEF. These simple profiles could therefore facilitate and promote advanced HF awareness among clinicians and planning for advanced HF therapies.

Minimally invasive surgery improves outcome of left ventricular assist device surgery in cardiogenic shock

Background

Left ventricular assist device (LVAD) (HVAD, Medtronic, Minneapolis, MN, USA) implantation is already a widely accepted treatment option for end-stage heart failure (HF) but also still considered as a rescue therapy for patients suffering from cardiogenic shock. Standard LVAD implantation techniques are often associated with high mortality rates and can result in severe complications, like bleeding or right heart failure (RHF). The aim of our study was to assess the outcome of Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) 1 patients (so called "crash and burn" patients) undergoing a LVAD implantation by standard or less invasive surgery.

Methods

We performed a retrospective evaluation of the 1-year outcome of 32 consecutive HF patients in cardiogenic shock, who underwent LVAD implantation in our institution. A total of 32 INTERMACS 1 patients were emergently operated. Fourteen patients (group A) were operated by using the "Hannover-VAD-technique", which is widely known to be less invasive (upper hemisternotomy and a left-sided anterolateral thoracotomy). In contrast, 18 patients (group B) were implanted with LVAD by using the standard technique (full sternotomy). The primary endpoint was survival after 1 year without device-related re-operations. Secondary endpoints included combined analyses of rates of RHF, respiratory failure and bleeding during the trial period.

Results

Baseline characteristics were similar in both groups. Survival after 1 year was higher in group A (69.7% vs. 50.0%). Technique-related adverse events (AEs) were also lower in the minimally invasive group, including a lower RHF (35.7% vs. 61.1%) and of further postoperative bleeding requiring surgery (14.3% vs. 33.3%).

Conclusions

LVAD surgery in INTERMACS 1 patients is associated with remarkably good outcome considering the already very high mortality of those patients, and compared to previously reported surgical outcomes. Our study indicates that minimally invasive LVAD implantation in cardiogenic shock decreases mortality and the incidence of postoperative AEs.

Derivation and Validation of a Novel Right-Sided Heart Failure Model After Implantation of Continuous Flow Left Ventricular Assist Devices

Background:

The aim of the study was to derive and validate a novel risk score for early right-sided heart failure (RHF) after left ventricular assist device implantation.

Methods:

The EUROMACS (European Registry for Patients with Mechanical Circulatory Support) was used to identify adult patients undergoing continuous-flow left ventricular assist device implantation with mainstream devices. Eligible patients (n=2988) were randomly divided into derivation (n=2000) and validation (n=988) cohorts. The primary outcome was early (<30 days) severe postoperative RHF, defined as receiving short- or long-term right-sided circulatory support, continuous inotropic support for ≥14 days, or nitric oxide ventilation for ≥48 hours. The secondary outcome was all-cause mortality and length of stay in the intensive care unit. Covariates found to be associated with RHF (exploratory univariate P <0.10) were entered into a multivariable logistic regression model. A risk score was then generated using the relative magnitude of the exponential regression model coefficients of independent predictors at the last step after checking for collinearity, likelihood ratio test, c index, and clinical weight at each step.

Results:

A 9.5-point risk score incorporating 5 variables (Interagency Registry for Mechanically Assisted Circulatory Support class, use of multiple inotropes, severe right ventricular dysfunction on echocardiography, ratio of right atrial/pulmonary capillary wedge pressure, hemoglobin) was created. The mean scores in the derivation and validation cohorts were 2.7±1.9 and 2.6±2.0, respectively ( P =0.32). RHF in the derivation cohort occurred in 433 patients (21.7%) after left ventricular assist device implantation and was associated with a lower 1-year (53% versus 71%; P <0.001) and 2-year (45% versus 58%; P <0.001) survival compared with patients without RHF. RHF risk ranged from 11% (low risk score 0–2) to 43.1% (high risk score >4; P <0.0001). Median intensive care unit stay was 7 days (interquartile range, 4–15 days) versus 24 days (interquartile range, 14–38 days) in patients without versus with RHF, respectively ( P <0.001). The c index of the composite score was 0.70 in the derivation and 0.67 in the validation cohort. The EUROMACS-RHF risk score outperformed ( P <0.0001) previously published scores and known individual echocardiographic and hemodynamic markers of RHF.

Conclusions:

This novel EUROMACS-RHF risk score outperformed currently known risk scores and clinical predictors of early postoperative RHF. This novel score may be useful for tailored risk-based clinical assessment and management of patients with advanced HF evaluated for ventricular assist device therapy.

Acute Biventricular Mechanical Circulatory Support for Cardiogenic Shock

BACKGROUND

Biventricular failure is associated with high in-hospital mortality. Limited data regarding the efficacy of biventricular Impella axial flow catheters (BiPella) support for biventricular failure exist. The aim of this study was to explore the clinical utility of percutaneously delivered BiPella as a novel acute mechanical support strategy for patients with cardiogenic shock complicated by biventricular failure.

METHODS AND RESULTS

We retrospectively analyzed data from 20 patients receiving BiPella for biventricular failure from 5 tertiary-care hospitals in the United States. Left ventricular support was achieved with an Impella 5.0 (n=8), Impella CP (n=11), or Impella 2.5 (n=1). All patients received the Impella RP for right ventricular (RV) support. BiPella use was recorded in the setting of acute myocardial infarction (n=11), advanced heart failure (n=7), and myocarditis (n=2). Mean flows achieved were 3.4±1.2 and 3.5±0.5 for left ventricular and RV devices, respectively. Total in-hospital mortality was 50%. No intraprocedural mortality was observed. Major complications included limb ischemia (n=1), hemolysis (n=6), and Thrombolysis in Myocardial Infarction major bleeding (n=7). Compared with nonsurvivors, survivors were younger, had a lower number of inotropes or vasopressors used before BiPella, and were more likely to have both devices implanted simultaneously during the same procedure. Compared with nonsurvivors, survivors had lower pulmonary artery pressures and RV stroke work index before BiPella. Indices of RV afterload were quantified for 14 subjects. Among these patients, nonsurvivors had higher pulmonary vascular resistance (6.8; 95% confidence interval [95% CI], 5.5-8.1 versus 1.9; 95% CI, 0.8-3.0; P<0.01), effective pulmonary artery elastance (1129; 95% CI, 876-1383 versus 458; 95% CI, 263-653; P<0.01), and lower pulmonary artery compliance (1.5; 95% CI, 0.9-2.1 versus 2.7; 95% CI, 1.8-3.6; P<0.05).

CONCLUSIONS

This is the largest, retrospective analysis of BiPella for cardiogenic shock. BiPella is feasible, reduces cardiac filling pressures and improves cardiac output across a range of causes for cardiogenic shock. Simultaneous left ventricular and RV device implantation and lower RV afterload may be associated with better outcomes with BiPella. Future prospective studies of BiPella for cardiogenic shock are required.

Contemporary Management of Cardiogenic Shock: A Scientific Statement From the American Heart Association

Cardiogenic shock is a high-acuity, potentially complex, and hemodynamically diverse state of end-organ hypoperfusion that is frequently associated with multisystem organ failure. Despite improving survival in recent years, patient morbidity and mortality remain high, and there are few evidence-based therapeutic interventions known to clearly improve patient outcomes. This scientific statement on cardiogenic shock summarizes the epidemiology, pathophysiology, causes, and outcomes of cardiogenic shock; reviews contemporary best medical, surgical, mechanical circulatory support, and palliative care practices; advocates for the development of regionalized systems of care; and outlines future research priorities.

Left Ventricular Assist Device in Older Adults

Left ventricular assist devices (LVADs) are an effective therapy for a growing and aging population in the background of limited donor supply. Selecting the proper patient involves assessment of indications, risk factors, scores for overall outcomes, assessment for right ventricular failure, and optimal timing of implantation. LVAD complications have a 5% to 10% perioperative mortality and complications of bleeding, thrombosis, stroke, infection, right ventricular failure, and device failure. As LVAD engineering technology evolves, so will the risk-prediction scores. Hence, more large-scale prospective data from multicenters will continually be required to aid in patient selection, reduce complications, and improve long-term outcomes.

Mechanical Circulatory Support: Heart Failure Therapy “in Motion”

Because the first generation of pulsatile-flow devices was primarily used to bridge the sickest patients to transplantation (bridge-to-transplant therapy), the current generation of continuous-flow ventricular assist devices qualifies for destination therapy for patients with advanced heart failure who are ineligible for transplantation. The first-generation devices were associated with frequent adverse events, limited mechanical durability, and patient discomfort due device size. In contrast, second-generation continuous-flow devices are smaller, more quiet, and durable, thus resulting in less complications and significantly improved survival rates. Heart transplantation remains an option for a limited number of patients only, and this fact has also triggered the discussion about the optimal timing for device implantation. The increasing use of continuous-flow devices has resulted in new challenges, such as adverse events during long-term support, and high hospital readmission rates. In addition, there are a number of device-related complications including mechanical problems such as device thrombosis, percutaneous driveline damage, as well as conditions such as hemolysis, infection, and cerebrovascular accidents. This review provides an overview of the evolution of mechanical circulatory support systems from bridge to transplantation to destination therapy including technological advances and clinical improvements in long-term patient survival and quality of life. In addition, recent changes in device implant strategies and current trials are reviewed and discussed. A brief glimpse into the future of mechanical circulatory support therapy will summarize the innovations that may soon enter clinical practice.

A Bayesian Model to Predict Right Ventricular Failure Following Left Ventricular Assist Device Therapy

OBJECTIVES

This study investigates the use of a Bayesian statistical model to address the limited predictive capacity of existing risk scores derived from multivariate analyses. This is based on the hypothesis that it is necessary to consider the interrelationships and conditional probabilities among independent variables to achieve sufficient statistical accuracy.

BACKGROUND

Right ventricular failure (RVF) continues to be a major adverse event following left ventricular assist device (LVAD) implantation.

METHODS

Data used for this study were derived from 10,909 adult patients from the Inter-Agency Registry for Mechanically Assisted Circulatory Support (INTERMACS) who had a primary LVAD implanted between December 2006 and March 2014. An initial set of 176 pre-implantation variables were considered. RVF post-implant was categorized as acute (<48 h), early (48 h to 14 daysays), and late (>14 days) in onset. For each of these endpoints, a separate tree-augmented naïve Bayes model was constructed using the most predictive variables employing an open source Bayesian inference engine.

RESULTS

The acute RVF model consisted of 33 variables including systolic pulmonary artery pressure (PAP), white blood cell count, left ventricular ejection fraction, cardiac index, sodium levels, and lymphocyte percentage. The early RVF model consisted of 34 variables, including systolic PAP, pre-albumin, lactate dehydrogenase level, INTERMACS profile, right ventricular ejection fraction, pro-B-type natriuretic peptide, age, heart rate, tricuspid regurgitation, and body mass index. The late RVF model included 33 variables and was predicted mostly by peripheral vascular resistance, model for end-stage liver disease score, albumin level, lymphocyte percentage, and mean and diastolic PAP. The accuracy of all Bayesian models was between 91% and 97%, with an area under the receiver operator characteristics curve between 0.83 and 0.90, sensitivity of 90%, and specificity between 98% and 99%, significantly outperforming previously published risk scores.

CONCLUSIONS

A Bayesian prognostic model of RVF based on the large, multicenter INTERMACS registry provided highly accurate predictions of acute, early, and late RVF on the basis of pre-operative variables. These models may facilitate clinical decision making while screening candidates for LVAD therapy.

Current Status of Left Ventricular Assist Device Therapy

Congestive heart failure (HF) remains a serious burden in the Western World. Despite advances in pharmacotherapy and resynchronization, many patients have progression to end-stage HF. These patients may be candidates for heart transplant or left ventricular assist device (LVAD) therapy. Heart transplants are limited by organ shortages and in some cases by patient comorbidities; therefore, LVAD therapy is emerging as a strategy of bridge to transplant or as a destination therapy in patients ineligible for transplant. Patients initially ineligible for a transplant may, in certain cases, become eligible for transplant after physiologic improvement with LVAD therapy, and a small number of patients with an LVAD may have sufficient recovery of myocardial function to allow device explantation. This clinically oriented review will describe (1) the most frequently used pump types and aspects of the continuous-flow physiology and (2) the clinical indications for and the shift toward the use of LVADs in less sick patients with HF. Additionally, we review complications of LVAD therapy and project future directions in this field. We referred to the Interagency Registry for Mechanically Assisted Circulatory Support, landmark trials, and results from recently published studies as major sources in obtaining recent outcomes, and we searched for related published literature via PubMed. This review focuses primarily on clinical practice for primary care physicians and non-HF cardiologists in the United States.

A Development of Nucleic Chromatin Measurements as a New Prognostic Marker for Severe Chronic Heart Failure

Background

Accurate prediction of both mortality and morbidity is of significant importance, but it is challenging in patients with severe heart failure. It is especially difficult to detect the optimal time for implanting mechanical circulatory support devices in such patients. We aimed to analyze the morphometric ultrastructure of nuclear chromatin in cardiomyocytes by developing an original clinical histopathological method. Using this method, we developed a biomarker to predict poor outcome in patients with dilated cardiomyopathy (DCM).

Methods and Results

As a part of their diagnostic evaluation, 171 patients underwent endomyocardial biopsy (EMB). Of these, 63 patients diagnosed with DCM were included in this study. We used electron microscopic imaging of cardiomyocyte nuclei and an automated image analysis software program to assess whether it was possible to detect discontinuity of the nuclear periphery. Twelve months after EMB, all patients with a discontinuous nuclear periphery (Group A, n = 11) died from heart failure or underwent left ventricular assist device (VAD) implantation. In contrast, in patients with a continuous nuclear periphery (Group N, n = 52) only 7 patients (13%) underwent VAD implantation and there were no deaths (p<0.01). We then evaluated chromatin particle density (Nuc-CS) and chromatin thickness in the nuclear periphery (Per-CS) in Group N patients; these new parameters were able to identify patients with poor prognosis.

Conclusions

We developed novel morphometric methods based on cardiomyocyte nuclear chromatin that may provide pivotal information for early prediction of poor prognosis in patients with DCM.

Hypertension: an unstudied potential risk factor for adverse outcomes during continuous flow ventricular assist device support

In end-stage heart failure, left ventricular assist devices (LVADs) represent an exciting new frontier in which post-device implantation survival approaches that of heart transplant. However, expansion of this technology is still limited by complications that impact morbidity and mortality. Thus, it is essential to identify and optimize modifiable predictors of poor outcomes. One such predictor may be hypertension (HTN). Not only may chronic HTN as a traditional cardiovascular risk factor be present during long-term LVAD support, but HTN may also contribute to device malfunction or device-associated complications. Although current guidelines identify blood pressure (BP) control as important to outpatient continuous flow (CF) LVAD management, there is no evidence base to support these guidelines. Indeed, our comprehensive literature search did not identify any studies that evaluated post-device implantation HTN as a potential predictor of adverse CF-LVAD outcomes. HTN among CF-LVAD patients is likely a relatively unstudied factor because of difficulties using standard noninvasive techniques to measure BP in the setting of reduced pulsatile flow. Fortunately, recent research has elucidated the meaning of Doppler BP measurements and validated a slow-cuff deflation system for BP measurements in the setting of CF-LVAD support. Therefore, CF-LVAD researchers and clinicians may (1) consider potential mechanisms relating HTN to poor outcomes, (2) realize that HTN management is a stated goal despite scarce evidence, and (3) utilize the new reliable and valid methods for outpatient BP measurement that make research and management possible. It is critical and now feasible that research on HTN in the CF-LVAD patient population move forward.

Left ventricular assist device implantation strategies and outcomes

Over the past 15 years, the field of mechanical circulatory support has developed significantly. Currently, there are a multitude of options for both short and long term cardiac support. Choosing the appropriate device for each patient depends on the amount of support needed and the goals of care. This article focuses on long term, implantable devices for both bridge to transplantation and destination therapy indications. Implantation strategies, including the appropriate concomitant surgeries are discussed as well as expected long term outcomes. As device technology continues to improve, long term mechanical circulatory support may become a viable alternative to transplantation.