Impaired heart rate variability one and six months post acute COVID-19

Background

Long COVID-19 syndrome is an increasingly recognized problem. Post-infectious cardiac autonomic dysfunction is commonly reported. This study aims to evaluate autonomic dysfunction by means of Heart rate variability (HRV) on post-COVID-19 patients.

Methods

Hospitalized patients for COVID-19 (either at the medical ward or Intensive Care Unit (ICU)) were followed up at 1 and 6 months after hospital discharge. Medical history and clinical information were collected. HRV was assessed by 24-hour ambulatory electrocardiography Holter, with the measure of the standard deviation of normal RR intervals in 24 h, ms (SDNN). The comparison was conducted with age and sex-matched non-COVID-19 controls.

Results

Thirty-four patients hospitalized with COVID-19 (20.6% admitted in ICU) were examined 1-month and 6-months post-hospital discharge. SDNN was significantly (p<0.001) reduced in the COVID-19 group (111±23 ms) compared to the control subjects (152±24 ms) 1-month after discharge. Subgroup analysis between COVID-19 group revealed that ICU subjects presented significantly (p<0.001) reduced SDNN compared to the medical ward, respectively (83±20 ms vs. 118±17 ms). At 6-months, an improvement was noted at SDNN 24h (6-month: 133±24 vs. control: 151±24 ms, p=0.004; 1-month: 111±23 ms vs. 6-month: 133±24 ms, p<0.001). Also at 6-months, ICU subjects noted significantly (p=0.003) reduced SDNN 24h compared to medical ward subjects (107±17 ms vs. 140±20 ms). On the 6-months follow-up, 32% of the subjects had “long-COVID-19” symptoms. Subjects with long COVID-19 symptoms had low SDNN values (“long-COVID-19”: 112±17 ms vs. non-“long-COVID-19”: 142±20 ms, p=0.001)

Conclusion

Patients hospitalized for COVID-19 have reduced SDNN, at one month post-hospital discharge which is improved at the six months follow-up. These findings emphasize the increased sympathetic drive activity in the post-acute COVID-19 phase and imply a link between autonomic dysfunction and long COVID-19.

Funding Acknowledgement

Type of funding sources: None.

Ventricular-arterial coupling impairment in patients recovered from COVID-19

Background

Myocardial and vascular alterations among post-COVID-19 patients are observed. The coupling between arterial stiffness with left ventricular (LV) myocardial function (ventricular-arterial coupling, VAC) is an important determinant of cardiovascular performance and cardiac energetics. The aim of the study was to investigate the spectrum of cardiac and vascular abnormalities at mid-term follow-up in post-COVID-19 patients.

Methods

We enrolled 25 hospitalized patients for COVID-19, at one and six months after hospital discharge. The ratio (PWV/GLS) of carotid-femoral pulse wave velocity (cf-PWV), as a marker of arterial stiffness, to global longitudinal strain (LV-GLS), as a marker of left ventricular performance, was estimated as a marker of arterial elastance/left ventricular elastance index the long-term. The comparison was conducted with age and sex-matched non-COVID-19 controls.

Results

There was no difference in age (56.8±11.6 y vs. 57.4±9.5 y; p=0.85) and male sex (64% vs. 68%; P=0.76) between post-COVID-19 and control subjects respectively. At one-month follow-up, significant impairment was noted between post-COVID-19 and control subjects regarding: VAC (−0.71±0.24 m/s% vs. −0.44±0.11 m/sec%; p&lt;0.001), LV-GLS (−17.9±3.1% vs. −21.9±2.7%; p&lt;0.001), cf-PWV (12.3±3.5 m/s vs. 9.6±1.9; p&lt;0.001). At six-month follow-up, an improvement was observed but there still was significant difference between post-COVID-19 and control subjects in: VAC (−0.62±0.19 m/sec% vs. −0.44±0.11 m/sec%; p&lt;0.001), LV-GLS (−19.3±2.9% vs. −21.9±2.7%; p=0.001), cf-PWV (11.7±2.7 m/s vs. 9.6±1.9 m/s; p=0.001). Moreover, it was observed at 1-month: VAC adverse correlation with the levels of IL-6 (r=−0.54; p&lt;0.001), CRP (−0.71; p=0.011) and at 6-months: IL-6 (r=−0.47; p=0.003), CRP (−0.56; p=0.007).

Conclusion

Ventricular-arterial coupling is impaired 6 months following COVID-19 highlighting the possible effects of SARS-CoV-2 infection in left ventricular mechanics and performance.

Funding Acknowledgement

Type of funding sources: None.

Blood pressure response in exercise is associated with future cardiac structural alterations in hypertensive patients

Background/Introduction

Exaggerated blood pressure response (EBPR) during the exercise treadmill test (ETT) is often observed in individuals without known cardiovascular disease. Although it is generally considered as an abnormal response and a risk factor for hypertension development, its clinical significance remains controversial. On the other hand, regression of left ventricular hypertrophy (LVH) is independently associated with improved cardiovascular outcome.

Purpose

In this study we aimed to investigate the role of EBPR during exercise in LVH regression in hypertensive subjects over time.

Methods

1413 hypertensive subjects, (mean age 57±11 years), 51% males, with baseline office blood pressure (BP) 144/89mmHg were followed for a mean period of 6.4±3.0 years. At baseline and last follow-up visit all patients underwent office BP, laboratory tests and echocardiographical determination of left ventricular mass index (LVMI). At baseline, all subjects underwent treadmill exercise testing (Bruce protocol) in order to identify the presence of EBPR based on the systolic BP elevation at peak exercise (&gt; or =210 mmHg for men and &gt; or =190 mmHg for women). Main outcome variable was LVH Regression/prevention (LVH Regr/prev), defined as: LVH at baseline visit with normal LVMI values at last visit or absence of LVH at baseline and last visit. BP control was considered optimal when the mean of office BP measurements during follow-up was &lt;140/90mmHg.

Results

46% of study population presented LVH Regr/prev during follow-up period. Cox-regression analysis, after adjustment for clinical and biochemical variables, revealed that low levels of baseline LVMI (HR=0.98, 95% CI 0.97–0.99, p&lt;0.0001), absence of EBPR (HR=0.81, 95% CI 0.67–0.98, p=0.02) and optimal BP control during follow-up (HR=1.19, 95% CI 1.01–1.56, p=0.03) were independent predictors of LVH Regr/prev during follow-up.

Conclusions

Beyond optimal BP control, EBPR is a significant predictor of left ventricular mass changes overtime. Hence, ETT can provide clinical relevant information, including EBPR, which may help in the improvement of risk stratification of hypertensive subjects.

Funding Acknowledgement

Type of funding source: None

Time in blood pressure range for different blood pressure targets and risk of cardiovascular disease: an analysis of a 7-year follow-up registry

Objective

Recent guideline recommendations have revisited the optimal target blood pressure (BP) for hypertensive patients. The Time in BP Range (TBPR) is an alternative metric for evaluation of long-term achieved BP. We investigated the association of TBPR for different levels of BP control with cardiovascular outcome among treated hypertensives.

Design and method

This is a retrospective analysis of 1202 treated hypertensive patients (age 59±11 years) without a history of cardiovascular disease followed for a mean period of 7±3 years. We calculated the TBPR [(No of Visits in BP range/ Total No of Visits) x 100%] for office systolic BP targets of 130–139mmHg, 120–129mmHg and &lt;120mmHg and examined the associated cardiovascular risk. The outcome studied was the composite of stroke and coronary artery disease. Time spent in systolic BP≥140mmHg served as the reference.

Results

In the entire population, mean TBPR for systolic BP 130–139mmHg, 120–129mmH, and &lt;120mmHg were 26%, 19% and 11% respectively. A TBPR of ≥50% for systolic BP 130–139mmHg, 120–129mmHg and &lt;120mmHg was observed in 332 (28%), 226 (19%) and 107 (9%) patients respectively. The composite endpoint occurred in 54 patients (4.5%). Patients with a TBPR for 120–140mmHg of ≥50% presented with a HR: 0.6 (95% CI: 0.34–1.06) for cardiovascular events. The TBPR of ≥50% for systolic BP 130–139mmHg, 120–129mmHg and &lt;120mmHg was associated with HR of 0.48 (95% CI: 0.23–1.01, p=0.05), 0.64 (95% CI: 0.29–1.39, p=0.26) and 0.72 (95% CI: 0.26–2.05) respectively. This pattern was sustained but further attenuated after controlling for standard risk factors. In comparison, a mean BP across visits of 130–139mmHg, 120–129mmHg and &lt;120mmHg was associated with a HR of 0.54 (5% CI: 0.28–1.03), 0.61 (95% CI: 0.29–1.26) and 0.80 (95% CI: 0.24–2.65).

Conclusions

Among treated hypertensives, a time in BP of 130–140mmHg of more than 50% is associated with the greatest reduction in cardiovascular risk. The TBPR is a potentially useful measure of BP control for evaluation of risk reduction in hypertensive patients.

Funding Acknowledgement

Type of funding source: None

The peculiar size and temperature dependence of water diffusion in carbon nanotubes studied with 2D NMR diffusion-relaxation D -T 2eff spectroscopy

It is well known that water inside hydrophobic nano-channels diffuses faster than bulk water. Recent theoretical studies have shown that this enhancement depends on the size of the hydrophobic nanochannels. However, experimental evidence of this dependence is lacking. Here, by combining two-dimensional nuclear magnetic resonance diffusion-relaxation ( D - T 2 e f f ) spectroscopy in the stray field of a superconducting magnet and molecular dynamics simulations, we analyze the size dependence of water dynamics inside Carbon Nanotubes (CNTs) of different diameters ( 1.1 - 6.0  nm), in the temperature range of 265 - 305  K. Depending on the CNT diameter, the nanotube water is shown to resolve in two or more tubular components acquiring different self-diffusion coefficients. Most notably, a favorable CNT diameter range ( 3.0 - 4.5  nm) is experimentally verified for the first time, in which water molecule dynamics at the center of the CNTs exhibits distinctly non-Arrhenius behavior, characterized by ultrafast diffusion and extraordinary fragility, a result of significant importance in the efforts to understand water behavior in hydrophobic nanochannels.

Posterior reversible encephalopathy syndrome as a complication of bacterial meningitis

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a clinical-radiological syndrome, which is presented with headache, seizures, altered mental consciousness, and visual disturbances, and is characterized by white matter vasogenic edema, predominantly affecting the posterior occipital and parietal lobes of the brain. This clinical syndrome is increasingly recognized due to the improvement and availability of brain imaging and, more specifically, magnetic resonance imaging.

CASE REPORT

We report the case of an otherwise healthy 20-year-old female who presented with fever, headache, and generalized arthralgia, raising the suspicion of Neisseria meningitidis serotype B meningitis, which was later complicated by PRES. The patient was treated with the antiepileptic drug levetiracetam, mannitol, and dexamethasone. Her mental status was completely restored in 3-4 days after the initiation of the treatment for PRES and was characterized by rapid clinical recovery.

CONCLUSION

PRES is a neurotoxic state characterized by a unique brain imaging pattern typically associated with a number of complex clinical conditions including infection, sepsis, and shock. The syndrome should be promptly recognized since it is reversible and treatable. HIPPOKRATIA 2019, 23(2): 131-134.

Human Leukocyte Antigen Compatibility and De Novo Donor-Specific Antibodies in Long-term Renal Transplant Patients With Stable Graft Function

PURPOSE

De novo donor-specific antibodies (DSA) are associated with antibody-mediated rejection leading to late renal transplant failure. The aim of this study was to evaluate whether HLA compatibility is associated with sensitization along with other risk factors.

METHODS

Eighty-nine stable renal transplant recipients (47 men) were studied. Patients were classified into 2 groups according to HLA compatibility between donor and recipient, group A (1-4/8 matches) and group B (5-8/8 matches). Cold ischemia time (CIT) and delayed graft function (DGF) were recorded along with time with a functional graft. Anti-HLA antibodies were detected using a Luminex single-antigen bead assay and were further classified into DSA and non-DSA.

RESULTS

HLA group A consisted of 49 (56%) transplant recipients while 38 (44%) were classified to group B, with functional grafts for 10.9 ± 6.7 and 14.8 ± 8.5 years, respectively (P = .019). Group A patients had more anti-HLA antibodies than group Β (P = .001) and this correlation was retained for DSA patients. De novo anti-HLA were detected in 40 patients; DSA were detected in 19 (21.8%). DSA (+) patients had recorded with functional renal grafts for 11 ± 5 years, compared to 14.4 ± 8.6 years (P = .048) for anti-HLA negative patients. Increased CIT and DGF were associated with anti-HLA antibodies detection but no with DSA.

CONCLUSION

HLA compatibility is probably correlated with DSA in a context of a more general anti-HLA sensitization, and both have a negative effect on long-term renal graft outcome.

Gravity as Gauge Theory Squared: A Ghost Story

The Becchi-Rouet-Stora-Tyutin (BRST) transformations and equations of motion of a gravity-two-form-dilaton system are derived from the product of two Yang-Mills theories in a BRST covariant form, to linear approximation. The inclusion of ghost fields facilitates the separation of the graviton and dilaton. The gravitational gauge fixing term is uniquely determined by those of the Yang-Mills factors which can be freely chosen. Moreover, the resulting gravity-two-form-dilaton Lagrangian is anti-BRST invariant and the BRST and anti-BRST charges anticommute as a direct consequence of the formalism.

Neuroradiological, neurophysiological and molecular findings in infantile Krabbe disease: two case reports

Krabbe disease is an autosomal recessive neurodegenerative disorder due to a defect of the lysosomal enzyme β-galactocerebrosidase (β-GALC). Depending on the age of onset, the disease is classified into infantile and later-onset forms. We report neuroradiological, neurophysiological and molecular findings in two Greek patients with the infantile form of Krabbe disease. The index patients presented at the age of 3.5 and 6 months, respectively, due to developmental delay. Magnetic resonance imaging (MRI) of the first patient’s brain demonstrated signs of leukodystrophy, while nerve conduction velocities (NCVs) were significantly decreased. The second patient’s MRI at the age of 4 months was initially normal, but at 18 months demonstrated leukodystrophic alterations as well, whereas NCVs were also significantly delayed. In both patients, a severe decrease in β-GALC, activity supported the diagnosis of Krabbe disease, while the final diagnosis was confirmed by molecular genetic testing. Two homozygous mutations of the GALC gene, the c.411_413delTAA [p.K139del] mutation in the first patient, and the c.749T>C [p.I250T] mutation in the second patient, were identified. At their last follow-up visit at the age of 4 and 6 years, respectively, both patients were bedridden and quadri-plegic, suffering from frequent respiratory tract infections and fed through a gastrostomy. Both mutations found in homozygosity in these two unrelated patients of Greek ancestry, could pinpoint a common origin. Genotyping of patients with Krabbe disease is important, in order to contribute to the creation of a European mutation database and to further study possible genotype-phenotype correlations of the disease.

Monitoring of compliance on an individual treatment through mobile innovations

The present work examines the potential of smartphone usage for offering health services to elderly patients. The purpose of this work is the design, development, and implementation of a telemedicine application. This application aims to improve the monitoring mode and increase patient adherence to the instructions assigned by the medical staff. It consists of three parts: the doctor's application (Web Application), the patient's application (Android Application) and the Web Server of the platform, where the database is stored necessary for the smooth operation of the platform. Also the Web Server hosts the doctor's Web Application. The Web Application is based on web front-end technologies, providing the medical personnel with a variety of features and useful actions. These actions and capabilities are mainly relevant to the assignment of instructions to patients and the monitoring of their health progress. The Android Application has been implemented and validated for the Android-based mobile devices operating system and consists of a handy and user-friendly environment, equipped with the right tools so that the patient has the ability to update the system on the progress of his/her health by storing the appropriate measurements. Both applications also provide customization capabilities in regards to the patients' and doctors' profile.

Yang-Mills origin of gravitational symmetries

By regarding gravity as the convolution of left and right Yang-Mills theories together with a spectator scalar field in the biadjoint representation, we derive in linearized approximation, the gravitational symmetries of general covariance, p-form gauge invariance, local Lorentz invariance, and local supersymmetry from the flat space Yang-Mills symmetries of local gauge invariance and global super-Poincaré symmetry. As a concrete example, we focus on the new minimal (12+12) off shell version of simple four-dimensional supergravity obtained by tensoring the off shell Yang-Mills multiplets (4+4, N_{L}=1) and (3+0, N_{R}=0).

Incidence of pituitary incidentalomas in patients with adrenal adenomas

With the advent of modern imaging modalities, endocrine incidentalomas are increasingly being discovered. We aimed to investigate the presence of pituitary incidentalomas (PI) in patients with adrenal incidentalomas (AI), and identify potential metabolic correlates in this cohort. 26 patients (18 females) with AI discovered on abdominal computerized tomography were studied. All patients underwent pituitary magnetic resonance imaging (MRI) and endocrine investigations to evaluate functional adrenal pathology, anterior pituitary hormonal status, insulin-resistance indices and presence of metabolic syndrome. Pituitary MRI revealed a microadenoma and a 4×5 mm cyst in 1 patient respectively, and an empty sella in 4 (2 partial) patients. Overall, 6/26 (23%) patients with an AI had evidence of pituitary imaging pathology but only 8% had a PI; none had any evidence of abnormalities in pituitary function. Subclinical hypercortisolism was the only hyperfunctional status detected in 4 patients with AI but was unrelated to the pituitary findings. No abnormality of insulin secretion and action was found between patients with or without pituitary pathology. In the present study 23% of patients with AI had some alteration in pituitary morphology, and 2 a PI without accompanying pituitary hormonal deficit or metabolic derangement. Further studies are required to address this issue and identify a potential pathogenetic mechanism.

Cerebral amyloid angiopathy

The aim of this report was to describe the case of an elderly patient with cerebral amyloid angiopathy and associated dementia who presented with new onset symptomatology compatible with an acute cerebrovascular event. Computed tomography scanning was suggestive of an incipient ischemic cerebrovascular event. Magnetic resonance imaging was requested due to the presence of small hyperdense lesions on CT, and revealed multiple diffuse hypodense parenchymal lesions with hemosiderin deposits, indicative of cerebral amyloid angiopathy. Diagnosis of the underlying pathology is of importance, as aspirin use, and antiplatelet use in general, may in these patients be associated with microbleed burden.

A patient with Lemierre syndrome

Lemierre syndrome, also known as postanginal sepsis, is a severe complication of an acute oropharyngeal infection that results in septic thrombophlebitis of the ipsilateral internal jugular vein with subsequent septicemia, often complicated by metastatic infections (Syed et al., Laryngoscope 117:1605-1610, 2007). We present the case of a previously healthy 12-year-old boy with Lemierre syndrome, caused by streptococci (Abiotrophia defectiva), complicating a subcutaneous neck abscess. The patient had metastatic sequelae, was treated with antibiotics (clindamycin and vancomycin) and low molecular weight heparin, and had an uneventful outcome.

Prevalence and correlates of depression in late life: a population based study from a rural Greek town

BACKGROUND

Depression in late life is common and has serious consequences on function, medical co-morbidity, quality of life, and use of medical services.

OBJECTIVE

To estimate the age- and gender-specific prevalence of depression among people over 60 years of age, and to examine correlates of depression, in particular the relationship between depression and cognitive impairment.

METHOD

From a total of 965 inhabitants, aged over 60 years, in Velestino, a rural town in central Greece, 608 were accessible and constituted the target population. During a five-month period in 2000, a trained health visitor interviewed all study participants. The interview covered socio-demographic characteristics, medical history, and administration of the 15-question Geriatric Depression Scale (GDS-15) and the Mini Mental Scale Examination instrument (MMSE).

RESULTS

The prevalence of mild or more severe depression (GDS> or =7) was 27%, while the prevalence of moderate to severe depression (GDS> or =11) was 12%. Increasing age, female gender, lower education, and being currently unmarried were associated with higher risk of depression in univariate regression models, but these associations disappeared after controlling for cognitive function, except for the association with marital status. Cognitive impairment was strongly associated with increased risk for depression. The co-morbid presence of digestive, neurological and heart conditions was also associated with increased risk for depression, while cancer was not.

CONCLUSION

In a rural Greek area, the prevalence of depression in late life is high. Depression was more common among unmarried individuals, those with significant cognitive impairment, and in association with specific medical conditions.

EX VIVO MAGNETIC RESONANCE IMAGING OF THE DISTAL ROW OF EQUINE CARPAL BONES: ASSESSMENT OF BONE SCLEROSIS AND CARTILAGE DAMAGE

The distal row of carpal bones (C2, C3, and C4) from eight left intercarpal joints--four from Standardbred Trotters and four from Swedish Warmblood horses--were used to assess the potential of magnetic resonance (MR) imaging to detect cartilage and bone lesions. The joints used in the study were classified by macroscopic and radiographic examinations as having normal, mild, moderate, or severe articular cartilage lesions and bone sclerosis. Those classifications correlated well with the appearance of the MR images. Bone sclerosis in the MR images was observed as regions of decreased signal intensity. Upon quantitative analysis of the MR images there was a significant difference (p < 0.0001) in the MR signal intensity from areas where radiographic bone sclerosis was observed compared to areas of radiographic nonsclerotic bone. In addition, the MR images were used to pilot the location of histology slices through areas of interest that were then examined microscopically; hence, the lesions found from the MR imaging examination were verified microscopically. It was concluded that cartilage lesions and cartilage loss are related to the sclerotic state of the underlying bone. The MR protocols developed in this study were applied on five intact cadaveric carpal joints, and it was concluded that MR imaging could successfully be used in the intact joint to detect minor cartilage and bone lesions not visualized by either radiography or macroscopic examination. Hence, MR imaging can be used to delineate interactions between articular cartilage and subchondral bone over time and in vivo.

Influence of haloperidol on the relationship of frontal lobe function to psychomotor poverty and disorganization syndromes

The aim of the study was to examine effects of haloperidol on the relationships between neuropsychological measures of frontal lobe functioning and the schizophrenia syndromes of psychomotor poverty and disorganization. Twenty-one participants with schizophrenia were initially evaluated when clinically stable and chronically treated with haloperidol, and 19 were evaluated again after a 3-week haloperidol-free period. Participants were evaluated with the Trail Making Test, the Wisconsin Card Sorting Test, the Purdue Pegboard, and psychiatric rating scales at each evaluation. There were significant correlations between schizophrenia syndromes and the tests sensitive to frontal lobe function when participants were medicated but not when drug-free. No significant changes in symptom severity or motor function occurred from the medication to the medication-free evaluation. The results indicate that haloperidol mediates the relationship between tests sensitive to frontal lobe function and the schizophrenia syndromes of psychomotor poverty and disorganization. This mediation effect was not attributable to changes in overall symptom severity or motor function.

Comparative study of SCE induction and cytostatic effects by homo-azasteroidal esters of N,N-bis(2-chloroethyl)aminobenzoic acid in human lymphocytes

The effect of homo-azasteroidal esters of benzoic acid mustard isomers and the 4-methyl derivatives, which have steroidal lactams as a biological basis, on cytogenetic damage was studied. Twenty compounds were comparatively studied, on a molar basis, as regards their ability to induce sister-chromatid exchanges (SCEs) and cell division delays. A correlation between potency for SCE induction, effectiveness in cell division delay and previously established antitumor activity of these compounds was observed.