Pulmonary Congestion on Lung Ultrasound Predicts Increased Risk of 30-Day Readmission in Heart Failure Patients.

OBJECTIVES: Heart failure exacerbations are a common cause of hospitalizations with a high readmission rate. There are few validated predictors of readmission after treatment for acute decompensated heart failure (ADHF). Lung ultrasound (LUS) is sensitive and specific in the assessment of pulmonary congestion; however, it is not frequently utilized to assess for congestion before discharge. This study assessed the association between number of B-lines, on LUS, at patient discharge and risk of 30-day readmission in patients hospitalized for acute decompensated heart failure (ADHF). METHODS: This was a single-center prospective study of adults admitted to a quaternary care center with a diagnosis of ADHF. At the time of discharge, the patient received an 8-zone LUS exam to evaluate for the presence of B-lines. A zone was considered positive if ≥3 B-lines was present. We assessed the risk of 30-day readmission associated with the number of lung zones positive for B-lines using a log-binomial regression model. RESULTS: Based on data from 200 patients, the risk of 30-day readmission in patients with 2-3 positive lung zones was 1.25 times higher (95% CI: 1.08-1.45), and in patients with 4-8 positive lung zones was 1.50 times higher (95% CI: 1.23-1.82, compared with patients with 0-1 positive zones, after adjusting for discharge blood urea nitrogen, creatinine, and hemoglobin. CONCLUSION: Among patients admitted with ADHF, the presence of B-lines at discharge was associated with a significantly increased risk of 30-day readmission, with greater number of lung zones positive for B-lines corresponding to higher risk.

Prospective Multicenter Study of Myocardial Recovery Using Left Ventricular Assist Devices (RESTAGE-HF [Remission from Stage D Heart Failure]): Medium-Term and Primary End Point Results.

BACKGROUND: Left ventricular assist device (LVAD) unloading and hemodynamic support in patients with advanced chronic heart failure can result in significant improvement in cardiac function allowing LVAD removal; however, the rate of this is generally considered to be low. This prospective multicenter nonrandomized study (RESTAGE-HF [Remission from Stage D Heart Failure]) investigated whether a protocol of optimized LVAD mechanical unloading, combined with standardized specific pharmacological therapy to induce reverse remodeling and regular testing of underlying myocardial function, could produce a higher incidence of LVAD explantation. METHODS: Forty patients with chronic advanced heart failure from nonischemic cardiomyopathy receiving the Heartmate II LVAD were enrolled from 6 centers. LVAD speed was optimized with an aggressive pharmacological regimen, and regular echocardiograms were performed at reduced LVAD speed (6000 rpm, no net flow) to test underlying myocardial function. The primary end point was the proportion of patients with sufficient improvement of myocardial function to reach criteria for explantation within 18 months with sustained remission from heart failure (freedom from transplant/ventricular assist device/death) at 12 months. RESULTS: Before LVAD, age was 35.1±10.8 years, 67.5% were men, heart failure mean duration was 20.8±20.6 months, 95% required inotropic and 20% temporary mechanical support, left ventricular ejection fraction was 14.5±5.3%, end-diastolic diameter was 7.33±0.89 cm, end-systolic diameter was 6.74±0.88 cm, pulmonary artery saturations were 46.7±9.2%, and pulmonary capillary wedge pressure was 26.2±7.6 mm Hg. Four enrolled patients did not undergo the protocol because of medical complications unrelated to the study procedures. Overall, 40% of all enrolled (16/40) patients achieved the primary end point, P<0.0001, with 50% (18/36) of patients receiving the protocol being explanted within 18 months (pre-explant left ventricular ejection fraction, 57±8%; end-diastolic diameter, 4.81±0.58 cm; end-systolic diameter, 3.53±0.51 cm; pulmonary capillary wedge pressure, 8.1±3.1 mm Hg; pulmonary artery saturations 63.6±6.8% at 6000 rpm). Overall, 19 patients were explanted (19/36, 52.3% of those receiving the protocol). The 15 ongoing explanted patients are now 2.26±0.97 years after explant. After explantation survival free from LVAD or transplantation was 90% at 1-year and 77% at 2 and 3 years. CONCLUSIONS: In this multicenter prospective study, this strategy of LVAD support combined with a standardized pharmacological and cardiac function monitoring protocol resulted in a high rate of LVAD explantation and was feasible and reproducible with explants occurring in all 6 participating sites. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01774656.

An early experience on the effect of solid organ transplant status on hospitalized COVID-19 patients.

We compared the outcome of COVID-19 in immunosuppressed solid organ transplant (SOT) patients to a transplant naïve population. In total, 10 356 adult hospital admissions for COVID-19 from March 1, 2020 to April 27, 2020 were analyzed. Data were collected on demographics, baseline clinical conditions, medications, immunosuppression, and COVID-19 course. Primary outcome was combined death or mechanical ventilation. We assessed the association between primary outcome and prognostic variables using bivariate and multivariate regression models. We also compared the primary endpoint in SOT patients to an age, gender, and comorbidity-matched control group. Bivariate analysis found transplant status, age, gender, race/ethnicity, body mass index, diabetes, hypertension, cardiovascular disease, COPD, and GFR <60 mL/min/1.73 m2 to be significant predictors of combined death or mechanical ventilation. After multivariate logistic regression analysis, SOT status had a trend toward significance (odds ratio [OR] 1.29; 95% CI 0.99-1.69, p = .06). Compared to an age, gender, and comorbidity-matched control group, SOT patients had a higher combined risk of death or mechanical ventilation (OR 1.34; 95% CI 1.03-1.74, p = .027).

Structural and functional cardiac changes in endomyocardial fibrosis treated with endomyocardial resection: Disease progression captured by multimodality imaging.

Eosinophilic myocarditis, a rare and under-recognized disease process, occurs due to cytotoxic inflammation of the endomyocardium that over time may lead to a restrictive cardiomyopathy. We report clinical, multimodality imaging, and pathologic findings in a 45-year-old woman over a 17-month period as she progressed from suspected acute eosinophilic myocarditis to phenotypic endomyocardial fibrosis resulting in recurrent ascites. Interval echocardiograms demonstrate definitive pathologic structural changes that reflect the hemodynamic consequences of the underlying cardiomyopathy. Despite a negative myocardial biopsy, characteristic findings on cardiovascular magnetic resonance imaging clarified the diagnosis which led to successful treatment with endomyocardial resection and valve replacements.

COVID-19 in recent heart transplant recipients: Clinicopathologic features and early outcomes.

BACKGROUND: The impact of COVID-19 on heart transplant (HTx) recipients remains unclear, particularly in the early post-transplant period. METHODS: We share novel insights from our experience in five HTx patients with COVID-19 (three within 2 months post-transplant) from our institution at the epicenter of the pandemic. RESULTS: All five exhibited moderate (requiring hospitalization, n = 3) or severe (requiring ICU and/or mechanical ventilation, n = 2) illness. Both cases with severe illness were transplanted approximately 6 weeks before presentation and acquired COVID-19 through community spread. All five patients were on immunosuppressive therapy with mycophenolate mofetil (MMF) and tacrolimus, and three that were transplanted within the prior 2 months were additionally on prednisone. The two cases with severe illness had profound lymphopenia with markedly elevated C-reactive protein, procalcitonin, and ferritin. All had bilateral ground-glass opacities on chest imaging. MMF was discontinued in all five, and both severe cases received convalescent plasma. All three recent transplants underwent routine endomyocardial biopsies, revealing mild (n = 1) or no acute cellular rejection (n = 2), and no visible viral particles on electron microscopy. Within 30 days of admission, the two cases with severe illness remain hospitalized but have clinically improved, while the other three have been discharged. CONCLUSIONS: COVID-19 appears to negatively impact outcomes early after heart transplantation.

An international survey to assess referral thresholds for destination therapy in non-inotrope-dependent patients: results of the CONSENSUS-DT study.

BACKGROUND: Criteria for the identification of patients who may progress to advanced heart failure (HF) have been previously suggested. However, identification of appropriate non-inotrope-dependent (NID) patients for destination therapy (DT) remains a challenge, and referral rates are low. We surveyed expert provider opinion about patient selection for early DT. METHODS: An internet-based survey was sent to international HF providers to investigate opinions about clinical indicators for referral of NID patients for DT. Subjects were identified from membership lists of HF professional organizations. Respondents provided their level of agreement with the use of a 5-point Likert Scale (1 = strongly disagree to 5 = strongly agree) to 10 clinical criteria describing at-risk NID patients. RESULTS: A total of 231 respondents who had been in a position to recommend left ventricular assist device (LVAD) therapy for 7.6 ± 5.8 years identified themselves as HF providers: 41% HF cardiologists, 27% HF nurse practitioners, 21% cardiothoracic surgeons, 9% LVAD coordinators, and 2% general cardiologists. More than two-thirds of the respondents agreed or strongly agreed with 7 of the 10 items. Similar consensus was not seen for 6-minute walk (6MW) or B-type natriuretic peptide (BNP). When asked which criteria would have to be present for LVAD referral, only hemodynamic deterioration reached ≥50% affirmation among respondents. No criteria reached >50% response as being sufficient alone for DT. CONCLUSION: We describe referral thresholds for early LVAD therapy among international HF providers. With the exception of BNP and 6MW, we found overall agreement on the proposed clinical parameters. Despite apparent consensus, in practice implantation rates for LVAD in NID patients remain low. The results of ongoing clinical trials in this population may lower thresholds for early referral for DT.

Impact of adverse events on ventricular assist device outcomes.

Left ventricular assist devices have been proven to be superior to medical therapy for advanced heart failure patients awaiting heart transplantation and viable alternatives to transplantation for destination therapy patients. Improvements in the design of ventricular assist devices have been rewarded by a decrease in adverse events and an increase in survival. Despite significant progress, even the latest generation left ventricular assist devices are burdened by a significant long-term adverse events profile that will increasingly challenge physicians as patients survive longer on implantable mechanical circulatory support. In this review, we analyze the impact of long-term adverse events on clinical outcomes in the major trials of continuous flow left ventricular assist devices. We discuss several of the more pertinent and interesting adverse events, examine their potential causes, and explore their future implications.

Subjective Assessment Underestimates Fraility in Patients With Heart Failure Referred for Advanced Therapies.

Assessment of frailty is key for evaluation for advanced therapies (ATs). Most programs use a subjective provider assessment (SPA) or "eye-ball" test; however, objective measures exist. The modified five-item Fried Frailty Index (mFFI) is a validated tool to assess frailty. We compared SPA to mFFI testing in patients referred for AT. We also compared levels of macrophage migration inhibitory factor (MIF), an inflammatory biomarker associated with worse outcomes in heart failure, between frail and not frail subjects. Seventy-eight patients referred for evaluation for AT underwent both SPA and mFFI testing. Three cardiac surgeons independently assessed patients for frailty (SPA). SPA significantly underestimated frailty compared with mFFI testing and correlation between SPA and mFFI was not strong (κ = 0.02-0.14). Providers were correct 84% of the time designating a subject as frail, but only 40% of the time designating as not frail. Agreement between all three providers was robust (76%), which was primarily driven by designation as not frail. There was no significant difference in plasma MIF levels between frail and not frail subjects (47.6 ± 25.2 vs . 45.2 ± 18.9 ng/ml; p = 0.6). Clinicians significantly underestimate frailty but are usually correct when designating a patient as frail.

Defining levels of care in cardiogenic shock.

Background: Expert opinion and professional society statements have called for multi-tier care systems for the management of cardiogenic shock (CS). However, little is known about how to pragmatically define centers with different levels of care (LOC) for CS. Methods: Eleven of 23 hospitals within our healthcare system sharing a common electronic health record were classified as different LOC according to their highest mechanical circulatory support (MCS) capabilities: Level 1 (L-1)-durable left ventricular assist device, Level 1A (L-1A)-extracorporeal membrane oxygenation, Level 2 (L-2)-intra-aortic balloon pump and percutaneous ventricular assist device; and Level 3 (L-3)-no MCS. All adult patients treated for CS (International Classification of Diseases, ICD-10 code R57.0) between 2016 and 2022 were included. Etiologies of CS were identified using associated diagnostic codes. Management strategies and outcomes across LOC were compared. Results: Higher LOC centers had higher volumes: L-1 (n = 1): 2,831 patients, L-1A (n = 4): 3,452, L-2 (n = 1): 340, and L-3 (n = 5): 780. Emergency room admissions were more common in lower LOC (96% at L-3 vs. 46% L-1; p < 0.001), while hospital transfers were predominant at higher LOC (40% at L-1 vs. 2.7% at L-3; p < 0.001). Men comprised 61% of the cohort. Patients were younger in the higher LOC [69 (60-78) years at L-1 vs. 77 (67-85) years at L-3; p < 0.001]. Patients with acute myocardial infarction (AMI)-CS and acute heart failure (AHF)-CS were concentrated in higher LOC centers while other etiologies of CS were more common in L-2 and L-3 (p < 0.001). Cardiac arrest on admission was more prevalent in lower LOC centers (L-1: 2.8% vs. L-3: 12.1%; p < 0.001). Patients with AMI-CS received more percutaneous coronary intervention in lower LOC (51% L-2 vs. 29% L-1; p < 0.01) but more coronary arterial bypass graft surgery at higher LOC (L-1: 42% vs. L-1A: 23%; p < 0.001). MCS use was consistent across levels for AMI-CS but was more frequent in higher LOC for AHF-CS patients (L-1: 28% vs. L-2: 10%; p < 0.001). Despite increasing in-hospital mortality with decreasing LOC, no significant difference was seen after multivariable adjustment. Conclusion: This is the first report describing a pragmatic classification of LOC for CS which, based on MCS capabilities, can discriminate between centers with distinct demographics, practice patterns, and outcomes. This classification may serve as the basis for future research and the creation of CS systems of care.

Improved exercise performance and skeletal muscle strength after simulated altitude exposure: a novel approach for patients with chronic heart failure.

BACKGROUND: Adaptation to altitude leads to beneficial physiologic changes that improve oxygen delivery and utilization by the periphery. Athletes have used simulated altitude enclosures as part of their training regimen to improve exercise performance. We hypothesized that changes due to acclimatization would also be beneficial for patients with heart failure (HF). We report the results of a pilot study of altitude exposure in patients with chronic HF. METHODS AND RESULTS: Subjects with chronic stable HF, left ventricular ejection fraction (LVEF) ≤35%, on optimal medical therapy were enrolled and underwent simulated altitude exposure for 10 sessions, each 3-4 hours, over a period of 22 days. Starting altitude was 1,500 m and was increased by 300 m with each subsequent session to a maximum altitude of 2,700 m. Peak oxygen consumption, 6-minute walk distance (6MW), skeletal muscle strength, quality of life scores, LVEF, and hematologic parameters were measured at baseline and 48 hours and 4 weeks after the final session. Twelve subjects (median age 52.5 y, ejection fraction 31.7%) successfully completed the protocol without any adverse effects. Peak oxygen consumption significantly improved after altitude sessions from 13.5 ± 1.8 to 14.2 ± 1.9 mL kg(-1) min(-1) (P = .036) and remained elevated after 4 weeks. There were significant improvements in exercise time, 6MW, skeletal muscle strength, and quality of life scores and a trend toward improvement in LVEF after completion of altitude sessions, which were sustained after 1 month. CONCLUSIONS: Simulated altitude exposure up to 2,700 m is safe and well tolerated in patients with chronic stable HF and may have beneficial effects on exercise performance, muscular strength, and quality of life.

Young patients with nonischemic cardiomyopathy have higher likelihood of left ventricular recovery during left ventricular assist device support.

BACKGROUND: Recovery of ventricular function during left ventricular assist device (LVAD) support allowing device explantation occurs infrequently. We explored the hypothesis that certain patient profiles are more likely to exhibit LV recovery during LVAD support. METHODS AND RESULTS: A retrospective analysis of data from the HeartMate II bridge to transplant (BTT) and destination therapy (DT) trials was conducted, including 490 BTT, 600 DT, and 18 compassionate-use patients. Of the 1,108 patients, 20 (1.8%; 10 BTT, 10 DT) were explanted owing to LV recovery. The median age was 33 years, and 12 patients (60%) were <40 years of age. History of heart failure was <1 year for 11 patients (61%), and the primary etiology was nonischemic (90%). Of the patients with nonischemic etiologies and <1-year history of heart failure, 13% were explanted. Three patients required LVAD reimplantation; of the remaining 17, 16 remain alive. At follow-up (median 510 days), the mean ejection fraction was 42% (20%-67%) and the mean left ventricular end-diastolic diameter was 55 ± 8 mm. At the 2-year follow-up (n = 13), patients were New York Heart Association functional class I or II and overall survival rate was 85 ± 11%. CONCLUSIONS: The results of this study suggest that LV recovery is most likely to occur in young patients (<40 years) with nonischemic cardiomyopathy of <1 year duration. Two-year postexplant survival was excellent.

Prospective evaluation of elastic restraint to lessen the effects of heart failure (PEERLESS-HF) trial.

BACKGROUND: Left ventricular (LV) remodeling predicts poor outcomes in heart failure (HF) patients. The HeartNet(®) cardiac restraint device (Paracor Medical Inc., Sunnyvale, CA) may reduce LV remodeling and improve functional capacity, quality of life, and outcomes in HF patients. To evaluate the safety and efficacy of the HeartNet Ventricular Support System in HF patients receiving optimal medical therapy. METHODS AND RESULTS: Prospective, randomized, controlled, multicenter trial in patients with symptomatic HF and LV ejection fraction ≤35% on optimal medical and device therapy. The primary efficacy end points were changes in peak VO(2), 6-minute walk (6MW) distance, and Minnesota Living with Heart Failure (MLWHF) quality of life score at 6 months. The primary safety end point was all-cause mortality at 12 months. Because the planned adaptive interim analysis of the first 122 subjects with a completed 6-month follow-up indicated futility to reach the peak VO(2) end point, trial enrollment was suspended. Hence, the results on the 96 treatment and 114 control subjects are reported. Groups were similar at baseline. At 6 months, responder frequency for a prespecified improvement was similar between groups for peak VO(2) (P = .502) and MLWHF score (P = .184) but borderline higher for improvement in 6MW distance in the treatment compared with the control group (33 [38%] vs. 25 [25%]; P = .044). At 6 months, the treatment group had a significantly greater improvement in Kansas City Cardiomyopathy Questionnaire (KCCQ) (P < .001) and decrease in LV mass (P = .032), LV end-diastolic diameter (P = .015), LV end-systolic diameter (P = .032), and LV end-diastolic volume (P = .031) as compared with controls. At 12 months, all-cause mortality and responder rates were similar in the 2 groups. Success rate for the HeartNet implantation was 99%. CONCLUSION: Enrollment in the trial was stopped because an interim analysis showed futility of reaching the peak VO(2) end point. However, because of the device safety and favorable signals for LV remodeling and quality of life, further investigation of this device is warranted.

Assessment of cardiac recovery in patients supported with venoarterial extracorporeal membrane oxygenation.

AIMS: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used to support patients in cardiogenic shock (CS). Early determination of disposition is paramount, as longer durations of support have been associated with worse outcomes. We describe a stepwise, bedside weaning protocol to assess cardiopulmonary recovery during VA-ECMO. METHODS AND RESULTS: Over 1 year, we considered all patients on VA-ECMO for CS for the Weaning Protocol (WP) at our centre. During the WP, patients had invasive haemodynamic monitoring, echocardiography, and blood gas analysis while flow was reduced in 1 LPM decrements. Ultimately, the circuit was clamped for 30 min, and final measures were taken. Patients were described as having durable recovery (DR) if they were free of pharmacological and mechanical support at 30 days post-decannulation. Over 12 months, 34 patients had VA-ECMO for CS. Fourteen patients were eligible for the WP at 4-12 days. Ten patients tolerated full flow reduction and were successfully decannulated. Twenty-four per cent of the entire cohort demonstrated DR with no adverse events during the WP. Patients with DR had significantly higher ejection fraction, cardiac index, and smaller left ventricular size at lowest flow during the WP. CONCLUSIONS: We describe a safe, stepwise, bedside weaning protocol to assess cardiac recovery during VA-ECMO. Early identification of patients more likely to recover may improve outcomes during ECMO support.

Increased incidence of gastrointestinal bleeding following implantation of the HeartMate II LVAD.

BACKGROUND: The HeartMate II (HMII) Left Ventricular Assist System (Thoratec Corporation, Pleasanton, CA, USA), an axial continuous-flow left ventricular assist device (LVAD), has been approved for use in bridge-to-transplant patients and is under investigation for destination therapy. To avoid device-related thromboembolic complications, antiplatelet, and anticoagulation therapy are routinely administered. A worrisome frequency of gastrointestinal (GI) bleeding events has been observed. METHODS: A retrospective review of all 33 patients undergoing long-term LVAD implantation between June 1, 2006 and July 31, 2008 at our institution for any indication was conducted. Anticoagulation consisted of heparin (intravenous or subcutaneous) followed by transition to Coumadin therapy to a target INR of two to three. Antiplatelet therapy consisted of low-dose aspirin and dipyridamole. RESULTS: Twenty patients received the HMII and 13 patients received other devices. Eight (40%) HMII recipients suffered at least one episode of GI bleeding while no GI bleeding occurred in recipients of other devices (p = 0.012). Of 17 total bleeding episodes, no definitive source could be identified in 11 instances (65%). CONCLUSIONS: Although definitive source identification remains elusive, we believe that the majority of bleeding arises in the small bowel, possibly due to angiodysplasias, similar to the pathophysiology encountered in patients with aortic stenosis and GI bleeding. As we move toward wider use of the HMII and other axial continuous-flow devices in both bridge-to-transplant patients and for destination therapy, more studies will be necessary to understand the mechanisms of this obscure GI bleeding and develop treatment strategies to minimize its development.

A multicenter study of noninvasive cardiac output by bioreactance during symptom-limited exercise.

BACKGROUND: Hemodynamic responses to exercise were assessed in patients with varying degrees of chronic heart failure (CHF) to determine the feasibility of using bioreactance during exercise testing in multicenter studies of CHF. METHODS AND RESULTS: A total of 210 symptomatic CHF patients and 22 subjects without heart failure were subjected to symptom-limited exercise testing on a bicycle (105) or treadmill (127) while measuring gas exchange for VO(2), cardiac output (CO) noninvasively by a bioreactance technique, heart rate, and blood pressure. Peak CO (pCO) and VO(2) (pVO(2)) during exercise were lower in patients with higher New York Heart Association (NYHA) class, in females and in older patients. Multiple linear regression analysis showed that pCO (L/min)=19.6+4.M -2.1.NYHA+1.9.G -0.09.Age, where M=1 for treadmill and 0 for bicycle and G=1 for males and 0 for females. Similarly, pVO(2) (mL/kg/min)=24+2.1.M -2.9.NYHA+1.26.G -0.08.Age. VO(2) and CO were also highly correlated to each other: pCO (mL/kg/min)=0.059+0.007.pVO(2)+0.036.M -0.025.G. Similar correlations were determined for other parameters of exercise, including left ventricular power, and the ratio of peak/resting VO(2) (cardiovascular reserve), the ratio of peak/resting CO (cardiac reserve), and total peripheral vascular resistance. CONCLUSION: Bioreactance-based noninvasive measurements of CO at rest and during exertion identified abnormalities of cardiovascular function consistent with those identified by pVO(2) and in prior studies using invasive CO measurements. This technique might therefore be useful for indexing disease severity, prognostication, and for tracking responses to treatment in clinical practice and in clinical trials.

Cardiac improvement during mechanical circulatory support: a prospective multicenter study of the LVAD Working Group.

BACKGROUND: Myocardial recovery after left ventricular assist device (LVAD) support has been reported. The LVAD Working Group Recovery Study was a prospective multicenter trial to assess the incidence of myocardial recovery in patients bridged to cardiac transplantation. METHODS AND RESULTS: After LVAD implantation, patients were evaluated with the use of rest echocardiograms with partial LVAD support and cardiopulmonary exercise testing. Dobutamine echocardiography with hemodynamic measurements was performed in those patients with left ventricular ejection fraction >40% during resting studies. Histological analysis was performed on myocardial samples taken at LVAD implantation and explantation. Sixty-seven LVAD patients with heart failure participated in the study. After 30 days, significant improvement occurred in left ventricular ejection fraction (17+/-7% versus 34+/-12%; P<0.001) and reductions in left ventricular end-diastolic diameter (7.1+/-1.2 versus 5.1+/-1.1 cm; P<0.001) and left ventricular mass (320+/-113 versus 194+/-79 g; P<0.001) compared with before LVAD. Thirty-four percent of patients had left ventricular ejection fraction >40% with partial device support. Left ventricular ejection fraction decreased over time to pre-LVAD measurement by 120 days. Peak VO2 improved with mechanical support (13.7+/-4.2 versus 18.9+/-5.5 mL/kg per minute, 30 versus 120 days; P<0.001). Tissue analysis revealed significant reductions in myocyte size, collagen content, and cardiac tumor necrosis factor-alpha. Six subjects (9%) underwent LVAD explantation for recovery. CONCLUSIONS: Cardiac function improves significantly after device implantation. Although cellular recovery and improvement in ventricular function are observed, the degree of clinical recovery is insufficient for device explantation in most patients with chronic heart failure.

Cardiac recovery during mechanical assist device support.

It is estimated that approximately 100,000 patients in the United States with advanced heart failure might benefit from cardiac transplantation, while donors are available for only 2000 recipients each year. Left ventricular assist devices (LVADs) are used both for bridge to transplantation and for long term support in patients ineligible for transplant. Both cardiac transplantation and long term LVAD therapy are limited by the complications of immunosuppression and device malfunction. Currently, a major focus of investigation in advanced heart failure is the temporary use of LVADs as a bridge to recovery of the native heart. While end-stage heart failure was once thought to be irreversible, research now suggests that LVAD support may lead to both cellular and functional recovery. Ultimately, patients with advanced cardiac disease might be managed with temporary mechanical support combined with pharmacological and cellular therapies, in place of cardiac transplantation or long term LVAD support. In this paper we review the evidence demonstrating the impact of LVAD support on the pathophysiology of end stage heart failure. Furthermore, we outline the clinical evidence for cardiac recovery seen in LVAD patients. Finally, we describe techniques to measure cardiac function during LVAD support and the criteria that have been suggested to select patients for device explantation for recovery.