Utility of routine evaluations for rejection in patients greater than 2 years after heart transplantation

AimsGuidelines support routine surveillance testing for rejection for at least 5 years after heart transplant (HT). In patients greater than 2 years post‐HT, we examined which clinical characteristics predict continuation of routine surveillance studies, outcomes following discontinuation of routine surveillance, and the cost‐effectiveness of different surveillance strategies.Methods and resultsWe retrospectively identified subjects older than 18 who underwent a first HT at our centre from 2007 to 2016 and who survived ≥760 days (n = 217) post‐HT. The clinical context surrounding all endomyocardial biopsies (EMBs) and gene expression profiles (GEPs) was reviewed to determine if studies were performed routinely or were triggered by a change in clinical status. Subjects were categorized as following a test‐based surveillance (n = 159) or a signs/symptoms surveillance (n = 53) strategy based on treating cardiologist intent to continue routine studies after the second post‐transplant year. A Markov model was constructed to compare two test‐based surveillance strategies to a baseline strategy of discontinuing routine studies. One thousand twenty studies were performed; 835 were routine. Significant rejection was absent in 99.0% of routine EMBs and 99.8% of routine GEPs. The treating cardiologist’s practice duration, patient age, and immunosuppressive regimen predicted surveillance strategy. There were no differences in outcomes between groups. Routine surveillance EMBs cost more and were marginally less effective than a strategy of discontinuing routine studies after 2 years; surveillance GEPs had an incremental cost‐effectiveness ratio of $1.67 million/quality‐adjusted life‐year.ConclusionsAcute asymptomatic rejection is rare after the second post‐transplant year. Obtaining surveillance studies beyond the second post‐transplant year is not cost‐effective.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156231/2/ehf212745.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156231/1/ehf212745_am.pd

Statin intensity and risk for cardiovascular events after heart transplantation

AimsStatins improve survival and reduce rejection and cardiac allograft vasculopathy after heart transplantation (HT). The impact of different statin intensities on clinical outcomes has never been assessed. We set out to determine the impact of statin exposure on cardiovascular outcomes after HT.Methods and resultsWe performed a retrospective study of 346 adult patients who underwent HT from 2006 to 2018. Statin intensity was determined longitudinally after HT based on American College of Cardiology/American Heart Association (ACC/AHA) guidelines. The primary outcome was the time to the first primary event defined as the composite of heart failure hospitalization, myocardial infarction, revascularization, and all‐cause mortality. Secondary outcomes included time to significant rejection and time to moderate–severe cardiac allograft vasculopathy. Adverse events were evaluated for subjects on high‐intensity statin therapy. A Cox proportional hazards model was used to evaluate the relationship between clinical variables, statin intensity, and outcomes. Most subjects were treated with low‐intensity statin therapy although this declined from 89.9% of the population at 1month after HT to 42.8% at 5years after HT. History of ischaemic cardiomyopathy, significant acute rejection, older donor age, and lesser statin intensity (p ≤ 0.001) were associated with reduced time to the primary outcome in a multivariable Cox model. Greater intensity of statin therapy was most beneficial early after HT. There were no statin‐related adverse events for the 14 subjects on high‐intensity statin therapy.ConclusionsGreater statin intensity was associated with a reduction in adverse cardiovascular outcomes after HT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162686/2/ehf212784.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162686/1/ehf212784_am.pd

Coronavirus Disease-2019 in Heart Transplant Recipients in Southeastern Michigan: A Case Series

BACKGROUND: Since coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China, in December 2019, the number of cases has risen exponentially. Clinical characteristics and outcomes among patients with orthotopic heart transplant (OHT) with COVID-19 remain poorly described. METHODS: We performed a retrospective case series of patients with OHT with COVID-19 admitted to 1 of 2 hospitals in Southeastern Michigan between March 21 and April 22, 2020. Clinical data were obtained through review of the electronic medical record. Final date of follow-up was May 7, 2020. Demographic, clinical, laboratory, radiologic, treatment, and mortality data were collected and analyzed. RESULTS: We identified 13 patients with OHT admitted with COVID-19. The mean age of patients was 61 ± 12 years, 100% were black males, and symptoms began 6 ± 4 days before admission. The most common symptoms included subjective fever (92%), shortness of breath (85%), and cough (77%). Six patients (46%) required admission to the intensive care unit. Two patients (15%) died during hospitalization. CONCLUSIONS: Black men may be at increased risk for COVID-19 among patients with OHT. Presenting signs and symptoms in this cohort are similar to those in the general population. Elevated inflammatory markers on presentation appear to be associated with more severe illness

Biorobotics: An Overview of Recent Innovations in Artificial Muscles

In this overview of recent developments in the field of biorobotics we cover the developments in materials such as the use of polyester fabric being used as artificial skin and the start of whole new ways to actuate artificial muscles as a whole. In this, we discuss all of the relevant innovations from the fields of nano and microtechnology, as well as in the field of soft robotics to summarize what has been over the last 4 years and what could be improved for artificial muscles in the future. The goal of this paper will be to gain a better understanding of where the current field of biorobotics is at and what its current trends in manufacturing and its techniques are within the last several years

Biorobotics: An Overview of Recent Innovations in Artificial Muscles

In this overview of recent developments in the field of biorobotics we cover the developments in materials such as the use of polyester fabric being used as artificial skin and the start of whole new ways to actuate artificial muscles as a whole. In this, we discuss all of the relevant innovations from the fields of nano and microtechnology, as well as in the field of soft robotics to summarize what has been over the last 4 years and what could be improved for artificial muscles in the future. The goal of this paper will be to gain a better understanding of where the current field of biorobotics is at and what its current trends in manufacturing and its techniques are within the last several years

Short‐term outcomes after sodium‐glucose cotransporter‐2 inhibitor initiation in a cohort of heart failure patients

Abstract Aims Sodium‐glucose cotransporter‐2 inhibitors (SGLT2i) decrease mortality and risk of hospitalization in patients with heart failure with reduced ejection fraction (HFrEF). SGLT2i have a natriuretic effect shortly after initiation, followed by a lasting osmotic diuretic effect. We sought to evaluate rates of acute kidney injury (AKI) and therapy discontinuation with SGLT2i initiation in a real‐world cohort of HFrEF patients. Methods and results We abstracted data on 200 patients with HFrEF initiated on a SGLT2i in the outpatient setting at the University of Michigan (between 1 July 2016 and 2 July 2022). Our co‐primary endpoints were rate of AKI and discontinuation of SGLT2i. A total of 200 patients were included. The majority of patients were male (64%) with a mean left ventricular ejection fraction (LVEF) of 27%. One hundred and four (52%) patients had diabetes mellitus. Most patients exhibited New York Heart Association class II (51.5%) or III (33.5%) symptoms. The majority of patients (54%) were taking an angiotensin‐receptor neprilysin inhibitor. The mean daily furosemide equivalent diuretic dose was 93.3 mg. AKI occurred in 22 patients and 18 patients discontinued their SGLT2i. Yeast infection (n = 6), hypotension (n = 5), and AKI (n = 4) were the most common reasons for discontinuation. Using receiver operating characteristic curve analysis, the strongest models for AKI were A1C [area underneath its curve (AUC) = 75.8, empirical confidence interval (ECI) 66.5–83.5]; baseline serum creatinine (SCr) (AUC = 72.0, ECI 65.7–78.7); LVEF (AUC = 67.6, ECI 58.4–75.8); and furosemide equivalent diuretic dose (AUC = 66.0, ECI 57.5–74.6). Similarly, the strongest positive models for SGLT2i discontinuation were A1C (AUC = 81.1, ECI 74.8–87.2); baseline SCr (AUC = 67.4, ECI 58.7–75.5); LVEF (AUC = 68.7, ECI 58.9–76.5); and furosemide equivalent diuretic dose (AUC = 67.2, ECI 58.2–76.0). Conclusions A1C was the strongest model of AKI, and SGLT2i discontinuation in HFrEF patients started on SGLT2i. Glucosuria may be related to this effect. Patients with higher baseline SCr on higher doses of loop diuretics may be at greater risk of these outcomes. Future prospective studies will be needed to further evaluate these findings and other models of AKI and SGLT2i discontinuation to guide clinical use of SGLT2 inhibitors

Reduced Myocardial Flow Reserve Is Associated With Diastolic Dysfunction and Decreased Left Atrial Strain in Patients With Normal Ejection Fraction and Epicardial Perfusion

INTRODUCTION: Coronary microvascular dysfunction (MVD) may contribute to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Using myocardial flow reserve (MFR) measured by positron emission tomography (PET) as an assessment of microvascular function, we hypothesized that abnormal MFR is associated with LV diastolic dysfunction (DD) and reduced LV and LA strain in patients with risk factors for HFpEF and normal epicardial perfusion on cardiac PET. METHODS AND RESULTS: Retrospective study of patients without heart failure who underwent cardiac rubidium-82 PET and echocardiography. Global MFR was calculated as the ratio of global stress to rest myocardial blood flow. Echocardiographic measures of diastolic function were recorded. Global longitudinal LA and LV strain were measured with a 2-dimensional speckle-tracking technique. Relationships among MFR and echocardiographic measures were assessed with linear regression, analysis of variance, and test for trend. Seventy-three patients (age 64 ± 11 years, 52% male) were identified with no epicardial perfusion defect on cardiac PET and an ejection fraction ≥50%. Decreased MFR was associated with LV DD (P = .02) and increased E/e\u27, an estimation of LV filling pressure (low E/e\u27 [15], P \u3c .001). MFR was associated with LA strain independent of age, gender, and common comorbidities (adjusted β = 2.6% per unit MFR, P = 0.046); however, MFR was only marginally related to LV strain. CONCLUSIONS: In patients with risk factors for HFpEF, MVD assessed with MFR was associated with DD, increased estimated LV filling pressure, and abnormal LA strain

Reduced Myocardial Flow Reserve Is Associated With Diastolic Dysfunction and Decreased Left Atrial Strain in Patients With Normal Ejection Fraction and Epicardial Perfusion

INTRODUCTION: Coronary microvascular dysfunction (MVD) may contribute to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Using myocardial flow reserve (MFR) measured by positron emission tomography (PET) as an assessment of microvascular function, we hypothesized that abnormal MFR is associated with LV diastolic dysfunction (DD) and reduced LV and LA strain in patients with risk factors for HFpEF and normal epicardial perfusion on cardiac PET. METHODS AND RESULTS: Retrospective study of patients without heart failure who underwent cardiac rubidium-82 PET and echocardiography. Global MFR was calculated as the ratio of global stress to rest myocardial blood flow. Echocardiographic measures of diastolic function were recorded. Global longitudinal LA and LV strain were measured with a 2-dimensional speckle-tracking technique. Relationships among MFR and echocardiographic measures were assessed with linear regression, analysis of variance, and test for trend. Seventy-three patients (age 64 ± 11 years, 52% male) were identified with no epicardial perfusion defect on cardiac PET and an ejection fraction ≥50%. Decreased MFR was associated with LV DD (P = .02) and increased E/e\u27, an estimation of LV filling pressure (low E/e\u27 [15], P \u3c .001). MFR was associated with LA strain independent of age, gender, and common comorbidities (adjusted β = 2.6% per unit MFR, P = 0.046); however, MFR was only marginally related to LV strain. CONCLUSIONS: In patients with risk factors for HFpEF, MVD assessed with MFR was associated with DD, increased estimated LV filling pressure, and abnormal LA strain