Heart transplantation and biomarkers: a review about their usefulness in clinical practice

Advanced heart failure (AdvHF) can only be treated definitively by heart transplantation (HTx), yet problems such right ventricle dysfunction (RVD), rejection, cardiac allograft vasculopathy (CAV), and primary graft dysfunction (PGD) are linked to a poor prognosis. As a result, numerous biomarkers have been investigated in an effort to identify and prevent certain diseases sooner. We looked at both established biomarkers, such as NT-proBNP, hs-troponins, and pro-inflammatory cytokines, and newer ones, such as extracellular vesicles (EVs), donor specific antibodies (DSA), gene expression profile (GEP), donor-derived cell free DNA (dd-cfDNA), microRNA (miRNA), and soluble suppression of tumorigenicity 2 (sST2). These biomarkers are typically linked to complications from HTX. We also highlight the relationships between each biomarker and one or more problems, as well as their applicability in routine clinical practice.

Biventricular or Conduction System Pacing for Cardiac Resynchronization Therapy: A Strategy for Cardiac Resynchronization Based on a Hybrid Approach

BACKGROUND

Cardiac resynchronization therapy (CRT) is usually performed with biventricular pacing (BiVP), but recently, conduction system pacing (CSP) has been proposed as an alternative in case of BiVP failure. The aim of this study is to define an algorithm to choose between BiVP and CSP resynchronization using the interventricular conduction delays (IVCD) as a guide.

METHODS

Consecutive patients from January 2018 to December 2020 with an indication for CRT were prospectively enrolled in the study group (delays-guided resynchronization group, DRG). A treatment algorithm based on IVCD was used to decide whether to leave the left ventricular (LV) lead to perform BiVP or pull it out and perform CSP. Outcomes from the DRG group were compared to a historical cohort of CRT patients who underwent CRT procedures between January 2016 and December 2017 (resynchronization standard guide group, SRG). The primary endpoint was a composite of cardiovascular mortality, heart failure (HF) hospitalization, or HF event at 1 year after the date of intervention.

RESULTS

The study population consisted of 292 patients, of which 160 (54.8%) were in the DRG and 132 (45.2%) in the SRG. In the DRG, 41 of 160 patients underwent CSP based on the treatment algorithm (25.6%). The primary endpoint was significantly higher in the SRG (48/132, 36.4%) compared to the DRG (35/160, 21.8%) (hazard ratio (HR): 1.72; 95% confidence interval (CI): 1.12-2.65; p = 0.013).

CONCLUSIONS

A treatment algorithm based on IVCD shifted one patient out of every four from BiVP to CSP, with consequent reduction in the primary endpoint after implantation. Therefore, its application could be useful to determine whether to perform BiVP or CSP.

Evidence of mitochondrial alterations in primary cardiac stromal cells from arrhythmogenic cardiomyopathy hearts

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This research was funded by the Department of Innovation, Research and University of the Autonomous Province of Bolzano-South Tyrol (Italy), and by the Joint Project Südtirol- FWF (Italy-Austria) for A.R., J.T., A.M., R.P..

Background

Arrhythmogenic cardiomyopathy (ACM) is a genetic disease associated with sudden cardiac death and fibro-fatty replacement of myocardium. Recently, it has been demonstrated that oxidized lipid contributes to cardiac adipogenesis and that ACM hearts are characterized by an increase in oxidative stress.

Purpose

As mitochondria are an important source of reactive oxygen species (ROS) within mammalian cells, the present work aims to evaluate if increased oxidative stress observed in ACM hearts is associated with altered mitochondrial function.

Methods

The oxidative stress marker 4HNE was investigated together with the cardiomyocyte marker cardiac Troponin T on paraffin embedded human ventricular samples and analyzed by confocal microscopy.

Human primary cardiac stromal cells (CStCs), obtained from either right ventricle biopsies of ACM patients or healthy cadaveric tissue donor (CTR), were used as cellular model as they are known for their contribution to adipogenesis in the ACM pathology. CStCs were cultured either in basal medium or adipogenic medium (ADIPO) in presence or absence of 500 nM of the ROS scavenger MitoTEMPO.

After 7 days of adipogenic differentiation, intracellular lipid droplets accumulation and mitochondrial superoxide levels were measured in CStCs by confocal microscopy using BODIPY 493/503 (0.5 µM) and MitoSOX Red (5 µM) dyes, respectively.

The oxidative phosphorylation (OXPHOS) and fatty acid oxidation (FAO) were also evaluated in CStCs by high resolution respirometry.

Results

4HNE staining was increased in heart tissues from ACM patients compared to CTRs and particularly evident in non-cardiomyocyte cells. In agreement, a higher MitoSOX fluorescence intensity was found in ACM-CStCs compared to CTR-CStCs in ADIPO medium, confirming higher ROS presence in patient cells. The treatment with MitoTEMPO was efficient in reducing ROS abundance, strongly suggesting mitochondrial origin. Lipid accumulation in ACM-CStCs was also prevented by MitoTEMPO treatment.

Preliminary evidence further indicates that mitochondrial respiratory capacity is increased in ACM-CStCs versus CTR-CStCs exposed to adipogenic medium for 7 days. However, transmission electron microscopy analysis and Western blot analysis of Mfn1/2, Opa1, Fis1 and Drp1 did not show an evident alteration neither in mitochondria ultrastructure nor in the expression of proteins regulating mitochondrial dynamics.

Conclusions

Our data support an alteration of mitochondrial activity in CStCs from ACM patients, apparently not linked to a modified network or morphology of mitochondria but associated with a higher ROS production.

Clinician approach to cardiopulmonary exercise testing for exercise prescription in patients at risk of and with cardiovascular disease

Exercise training is highly recommended in current guidelines on primary and secondary prevention of cardiovascular disease (CVD). This is based on the cardiovascular benefits of physical activity and structured exercise, ranging from improving the quality of life to reducing CVD and overall mortality. Therefore, exercise should be treated as a powerful medicine and critical component of the management plan for patients at risk for or diagnosed with CVD. A tailored approach based on the patient's personal and clinical characteristics represents a cornerstone for the benefits of exercise prescription. In this regard, the use of cardiopulmonary exercise testing is well-established for risk stratification, quantification of cardiorespiratory fitness and ventilatory thresholds for a tailored, personalised exercise prescription. The aim of this paper is to provide a practical guidance to clinicians on how to use data from cardiopulmonary exercise testing towards personalised exercise prescriptions for patients at risk of or with CVD.

Different Renal Function Patterns in Patients With Acute Heart Failure: Relationship With Outcome and Congestion

Background

The role of worsening renal function during acute heart failure (AHF) hospitalization is still debated. Very few studies have extensively evaluated the renal function (RF) trend during hospitalization by repetitive measurements.

Objectives

To investigate the prognostic relevance of different RF trajectories together with the congestion status in hospitalized patients.

Methods

This is a post hoc analysis of a multi-center study including 467 patients admitted with AHF who were screened for the Diur-AHF Trial. We recognized five main RF trajectories based on serum creatinine and estimated glomerular filtration rate (eGFR) behavior. According to the RF trajectories our sample was divided into 1-stable (S), 2-transient improvement (TI), 3-permanent improvement (PI), 4-transient worsening (TW), and 5-persistent worsening (PW). The primary outcome was the combined endpoint of 180 days including all causes of mortality and re-hospitalization.

Results

We recruited 467 subjects with a mean congestion score of 3.5±1.08 and a median creatinine value of 1.28 (1.00-1.70) mg/dl, eGFR 50 (37-65) ml/min/m2 and NTpro B-type natriuretic peptide (BNP) 7,000 (4,200-11,700) pg/ml. A univariate analysis of the RF pattern demonstrated that TI and PW patterns were significantly related to poor prognosis [HR: 2.71 (1.81-4.05); p < 0.001; HR: 1.68 (1.15-2.45); p = 0.007, respectively]. Conversely, the TW pattern showed a significantly protective effect on outcome [HR:0.34 (0.19-0.60); p < 0.001]. Persistence of congestion and BNP reduction ≥ 30% were significantly related to clinical outcome at univariate analysis [HR: 2.41 (1.81-3.21); p < 0.001 and HR:0.47 (0.35-0.67); p < 0.001]. A multivariable analysis confirmed the independently prognostic role of TI, PW patterns, persistence of congestion, and reduced BNP decrease at discharge.

Conclusions

Various RF patterns during AHF hospitalization are associated with different risk(s). PW and TI appear to be the two trajectories related to worse outcome. Current findings confirm the importance of RF evaluation during and after hospitalization.

572 Different renal function patterns in acute heart failure patients

Aims

The role of worsening renal function during acute heart failure (AHF) hospitalization is still debated. Very few studies have extensively evaluated the renal function (RF) trend during hospitalization by repetitive measurements. The aim of this study is to investigate the prognostic relevance of different RF trajectories together with the congestion status in hospitalized patients.

Methods and results

This is a post hoc analysis of a multi-centres study including 467 patients admitted with AHF who were screened for the Diur-AHF Trial. We recognized five main RF trajectories based on serum creatinine and estimated glomerular filtration rate (eGFR) behaviour: according to the RF curve our sample was divided into 1-stable (S), 2-transient improvement (TI), 3-permanent improvement (PI), 4-transient worsening (TW), and 5-persistent worsening (PW). The primary outcome was the combined endpoint of 180 days including all causes of mortality and re-hospitalization.

We recruited 467 subjects with a mean congestion score of 3.5 ± 1.08 and a median creatinine value of 1.28 (1.00–1.70) mg/dl, eGFR 50 (37–65) ml/min/m2, and NTpro BNP 7000 (4200–11 700) pg/ml. A univariate analysis of the RF pattern demonstrated that TI and PW patterns were significantly related to poor prognosis [HR: 2.71 (1.81–4.05); P &lt; 0.001; HR: 1.68 (1.15–2.45); P = 0.007, respectively]. Conversely, the TW pattern showed a significantly protective effect on outcome [HR: 0.34 (0.19–0.60); P &lt; 0.001]. Persistence of congestion and BNP reduction ≥ 30% were significantly related to clinical outcome at univariate analysis [HR: 2.41 (1.81–3.21); P &lt; 0.001 and HR: 0.47 (0.35–0.67); P &lt; 0.001]. A multivariable analysis confirmed the independently prognostic role of TI, PW patterns, persistence of congestion and reduced BNP decrease at discharge.

Conclusions

Various RF patterns during AHF hospitalization are associated with different risk(s). PW and TI appear to be the two trajectories related to worse outcome. Current findings confirm the importance of RF evaluation during and after hospitalization.

[Cardiopulmonary exercise testing: an essential tool for a tailored exercise prescription in patients with cardiac disease]

Cardiovascular diseases are the leading cause of death in high-income countries. Exercise prescription is an effective tool for primary and secondary cardiovascular prevention and the cardiovascular benefits of physical activity are well established, ranging from improving the quality of life to reducing mortality. A tailored approach based on patient's personal and clinical characteristics represents a cornerstone for the benefits of exercise prescription. The use of cardiopulmonary exercise testing is well-established for a tailored exercise prescription, as ventilatory thresholds allow to define exercise intensity in a highly individualized manner.

The importance of ventilatory thresholds to define aerobic exercise intensity in cardiac patients and healthy subjects

BACKGROUND

Although structured exercise training is strongly recommended in cardiac patients, uncertainties exist about the methods for determining exercise intensity (EI) and their correspondence with effective EI obtained by ventilatory thresholds. We aimed to determine the first (VT₁ ) and second ventilatory thresholds (VT₂ ) in cardiac patients, sedentary subjects, and athletes comparing VT₁ and VT₂ with EI defined by recommendations.

METHODS

We prospectively enrolled 350 subjects (mean age: 50.7±12.9 years; 167 cardiac patients, 150 healthy sedentary subjects, and 33 competitive endurance athletes). Each subject underwent ECG, echocardiography, and cardiopulmonary exercise testing. The percentages of peak VO₂ , peak heart rate (HR), and HR reserve were obtained at VT₁ and VT₂ and compared with the EI definition proposed by the recommendations.

RESULTS

VO₂ at VT₁ corresponded to high rather than moderate EI in 67.1% and 79.6% of cardiac patients, applying the definition of moderate exercise by the previous recommendations and the 2020 guidelines, respectively. Most cardiac patients had VO₂  values at VT₂ corresponding to very-high rather than high EI (59.9% and 50.3%, by previous recommendations and 2020 guidelines, respectively). A better correspondence between ventilatory thresholds and recommended EI domains was observed in healthy subjects and athletes (90% and 93.9%, respectively).

CONCLUSIONS

EI definition based on percentages of peak HR and peak VO₂  may misclassify the effective EI, and the discrepancy between the individually determined and the recommended EI is particularly relevant in cardiac patients. A ventilatory threshold-based rather than a range-based approach is advisable to define an appropriate level of EI.

The importance of first and second ventilatory thresholds to define aerobic exercise intensity in cardiac patients and in healthy subjects: what is essential can be visible to the eyes

Funding Acknowledgements

Type of funding sources: None.

Background. Although structured exercise training is strongly recommended in cardiac patients, uncertainties exist about the methods for determining exercise intensity (EI) and their correspondence with effective EI obtained by ventilatory thresholds. We aimed to determine the first (VT1) and second ventilatory threshold (VT2) in cardiac patients, sedentary subjects and athletes comparing VT1 and VT2 with EI defined by recommendations.

Methods. We prospectively enrolled 350 subjects (mean age: 50.7 ± 12.9 years; 167 cardiac patients, 150 healthy sedentary subjects, 33 competitive endurance athletes). Each subject underwent ECG, echocardiography, and cardiopulmonary exercise testing. The percentages of peak VO2, peak heart rate (HR), and HR reserve were obtained at VT1 and VT2, and compared with EI definition proposed by the recommendations.

Results. VO2 at VT1 corresponded to high rather than moderate EI in 67.1% and in 79.6% of cardiac patients, applying the definition of moderate exercise by the previous recommendations and the 2020 guidelines, respectively. Most of cardiac patients had VO2 values at VT2 corresponding to very-high rather than high EI (59.9% and 50.3%, by previous recommendations and 2020 guidelines, respectively). A better correspondence between ventilatory-thresholds and recommended EI domains was observed in healthy subjects and in athletes (90% and 93.9%, respectively).

Conclusions. EI definition based on percentages of peak HR and peak VO2 may misclassify the effective EI and the discrepancy between the individually determined and the recommended EI is particularly relevant in cardiac patients. A ventilatory threshold-based rather than a range-based approach is advisable in order to define an appropriate level of EI.

Abstract Figure.

Sacubitril/Valsartan in an Elderly Patient with Heart Failure: A Case Report

Sacubitril/valsartan has recently been approved for the treatment of heart failure with reduced ejection fraction. Given its recent introduction in the armamentarium for the treatment of heart failure (HF), "field-practice" evidence is required to deepen the clinical management of sacubitril/valsartan therapy. We report a relevant case of an elderly patient who achieved major clinical benefits after only 3 months of sacubitril/valsartan therapy. Importantly, in our assessment, we employed speckle tracking echocardiography (STE), a recent echocardiography technique that is non-Doppler and not angle dependent, which analyzes deformations of heart chambers from standard images and allows a fast, reliable, and reproducible assessment of heart function. After 3 months of therapy, NHYA class decreased from III to I-II and hypertension was controlled. Echocardiography examination also showed a marked improvement, with a reduction of left ventricular diameter, improved diastolic function (E = 0.39 m/s; A 0.69 m/s; E/A 0.55), normalized diastolic function index (E/E' TDI = 6.93), normalized atrial volume (63 mL), and improved atrial strain (15.44%). This case report documents the fast clinical and symptom improvement with sacubitril/valsartan in an elderly patient with HF; comprehensive echocardiographic assessment, including STE, also revealed a marked functional improvement with this compound.

Influence of aetiology on long-term effects of resynchronization on cardiac structure and function in patients treated with β-blockers

OBJECTIVES

Cardiac resynchronization therapy (CRT) elicits more beneficial effects on left-ventricular (LV) structure and function, and long-term clinical outcomes in nonischemic heart failure patients. Rates of β-blocker use in recent heart failure trials are higher than in CRT trials and this may influence the response to CRT. This study examined the long-term effects of CRT on LV structure and function in New York Heart Association class III-IV β-blocker-treated patients.

METHODS

One hundred and four (41 ischemic and 63 nonischemic) CRT patients, who were receiving β-blockers before and throughout 12 months following device implantation, were retrospectively selected. Variations in echocardiographic parameters recorded before, and 6 and 12 months after CRT were analyzed.

RESULTS

Selected patients were all stable on β-blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (97%) and diuretics (97%) before implantation. CRT was associated with significant improvements in LV morphological and systo-diastolic functional parameters at 6 months, with further improvements between 6 and 12 months seen in nonischemic patients only. Accordingly, rates of echocardiographic response to CRT were similar at 6 months but significantly higher in nonischemic patients after 1 year. The degree of reduction in LV diameters and volumes, and of increase in ejection fraction, was significantly larger in nonischemic patients at both 6 and 12 months. In addition, a significant reduction in LV mass and severity of mitral regurgitation was more evident in nonischemic patients both 6 and 12 months following CRT.

CONCLUSIONS

Ischemic aetiology of heart failure is associated with less favorable long-term effects of CRT on LV structure and function despite the systematic use of β-blockers.

Intracranial hypertension and cryptococcal meningitis in a girl with AIDS

A girl with HIV infection acquired at birth by blood transfusion, was admitted at the age of 10 years for diplopia, vomiting, headache and papilledema. CT scan was negative. A lumbar puncture revealed clear CSF, protein 0.40 g/l, glucose 2 mmol/l, 5 mononuclear cells/mm3. The Indian ink preparation and the latex agglutination antigen test were positive for Cryptococcus n. Treatment with amphotericin B and flucytosine was started. After 10 days, since the in vitro susceptibility testing of the isolates showed resistence to both drugs, fluconazolo (400 mg/day) was started. Acetazolamide, furosemide and spironolactone were then added to the antifungal therapy for the persistence of severe intracranial hypertension. Diuretics were maintained for 10 weeks. The patient returned to school two and half months after the admission to the hospital. After 19 months, she is doing well and she is on maintenance of fluconazole (200 mg/day). We hypothesized that the increased intracranial pressure would be due to an impaired CSF reabsorption probably as a consequence of a direct cryptococcal infiltration of the villi.

Antibody responses to Haemophilus influenzae type b and Streptococcus pneumoniae vaccines in children with human immunodeficiency virus infection

Antibody responses to Haemophilus influenzae type b (Hib) conjugate (ActHIB; Pasteur Merieux) and pneumococcal (Pneumovax II; Morson) vaccines were measured in 56 infected children (VI) and 44 uninfected children (U) older than 18 months of age, born to human immunodeficiency virus-positive mothers. Preimmunization, 21% U and 20% VI had protective concentrations of anti-Hib polysaccharide antibodies. Postimmunization, 100% U and 86% VI achieved protective titers (P = 0.008). The geometric mean increase in anti-Hib polysaccharide antibody was 7.6 (95% confidence interval, 3.5 to 16.3; P = 0.0001) times higher in U than in VI children after adjusting for age and ethnicity. Sixty-one percent U compared to 54% VI showed a 2-fold increase in antibody levels to at least one of the four pneumococcal vaccine serotypes (3, 6, 19, 23) measured (P = 0.4). For both vaccines there was a significant trend toward poorer responses in children with acquired immunodeficiency syndrome but no correlation with age adjusted CD4 counts. These data suggest that human immunodeficiency virus-infected children should be immunized with these polysaccharide vaccines early in the course of their disease.

Cerebrospinal fluid analysis in HIV-1-infected children: immunological and virological findings before and after AZT therapy

Immunological and viral studies were conducted on cerebrospinal fluid from 31 HIV-1-infected children, of whom 23 were neurologically asymptomatic and 8 had progressive encephalopathy. After AZT treatment, a second cerebrospinal fluid specimen was obtained from 15 children, 11 of whom were neurologically asymptomatic and 4 had progressive encephalopathy. Virus isolation and p24Ag detection were more frequent in children with progressive encephalopathy than in asymptomatic children (66% versus 12%) and were inversely correlated with intrathecal HIV-1-antibody detection (anti-gag AB: 25% versus 70%). High concentrations of interleukin-1 beta (IL-1 beta) and IL-6 were found in children with progressive encephalopathy (50% and 37%, respectively), but low levels were also detected in some asymptomatic children (13% and 9%, respectively). Tumour necrosis factor-alpha (TNF alpha) was not found. AZT treatment induced disappearance of p24Ag in cerebrospinal fluid, as well as a marked reduction in cytokine levels. Cytokine determination may be useful in monitoring AZT treatment in children with progressive encephalopathy.

The use of antibiotics in the treatment and prevention of infection in HIV-infected children

Children with HIV infection have an unusual susceptibility to bacterial infection, related to several immune abnormalities. Selection of initial antibiotic therapy must be individualized in these children. Patients with community-acquired disease are most likely to have infection by polysaccharide-encapsulated bacterial organism, most commonly Streptococcus pneumoniae and less frequently by Haemophilus influenzae type b. If it is possible to treat the patients at home, the use of amoxicillin-clavulanic acid might be appropriate. Other authors propose management with parenteral ceftriaxone because of the better compliance and the malabsorption. In hospitalized patients, concern for Gram-negative enteric pathogens other than polysaccharide-encapsulated organisms requires initial therapy with a third-generation cephalosporine in combination with an aminoglycoside. Trimethoprim-sulfamethizole is the most common drug used in HIV-infected children because it is recommended for the initial therapy and for prophylaxis of pneumocystis carinii pneumonia, which occurs in as many as 42% of these children.