Long-term outcomes in patients with potential reversible causes of bradycardia

Funding Acknowledgements

Type of funding sources: None.

Introduction

Hyperkalemia and negative chronotropic drugs are well known causes of reversible bradycardia. Their synergic combination may result in BRASH syndrome (Bradycardia, Renal failure, Atrioventricular blockade, Shock, and Hyperkalemia), a consequence of the vicious cycle between bradycardia, renal failure and worsening hyperkalemia, leading ultimately to multiorgan dysfunction. In potentially reversible bradycardia, drug discontinuation or metabolic correction is recommended before permanent pacemaker (PPM) implantation.

Objectives

To determine the long-term prognosis in patients with potentially reversible symptomatic bradycardia.

Methods

We retrospectively reviewed 176 patients who presented to the emergency department with symptomatic bradycardia, between January 2015 and August 2016. Patients without any reversible cause of bradycardia were excluded. Participants were stratified into three groups according to the reversible causes of bradycardia: patients with hyperkalemia, with or without acute renal injury (ARI) (group 1); patients taking negative chronotropic drugs, with or without ARI (group 2); patients with BRASH syndrome (combination of hyperkalemia and negative chronotropic drugs, with or without ARI) (group 3). The primary endpoint was PPM implantation after discharge. Secondary endpoints included: bradycardia-related rehospitalization, heart failure (HF) hospitalization, all-cause mortality and a composite of all the previous endpoints.

Results

A total of 105 patients were included (52.4% female; mean age 79.8±8.6 years). Group 1 was comprised by 15 patients (14.3%), group 2 by 69 patients (65.7%) and group 3 by 21 patients (20%, figure 1). The incidence of each event is presented in figure 2. During a mean follow-up of 3.2±2.1 years, PPM was implanted in 60 patients (57.1%) – 51 during hospital stay (85%) and 9 after discharge (15%). Across all groups, approximately 50% of the patients needed PPM implantation at some point, without significant differences between groups (p=0.508). Group 3 had the lowest need of in-hospital PPM (38.1%) but the highest bradycardia-related readmissions (9.5%). Nevertheless, post-discharge PPM implantation was still higher in group 1 (33.3%), followed by group 3 (22.2%). There were no significant differences in the post-discharge PPM implantation rate between groups (p=0.76). In groups 1 and 3 the composite endpoint (73.3% and 76.2%, respectively) was significantly more frequent than in group 2 (44.9%, p=0.046 and p=0.012, respectively).

Conclusions

Nearly half of the patients with an episode of reversible bradycardia needed a PPM at some point. Given the advanced age of most patients with bradycardia secondary to metabolic derangement and/or drug toxicity, it is possible that this unveils underlying conduction system disease, which is likely to recur without PPM implantation.

Clinical and echocardiographic features of platypnea-orthodeoxia syndrome: a single-centre experience

Funding Acknowledgements

Type of funding sources: None.

Background

Platypnea-orthodeoxia syndrome (POS) is an uncommon condition characterized by dyspnoea and hypoxemia in the upright position that improves with recumbency.1 Possible causes are intracardiac shunt, pulmonary arteriovenous shunt, and V/Q mismatch.1,2 Echocardiography is the cornerstone of POS diagnosis, with special focus on atrial septal defect (ASD) morphology and right-to-left shunt confirmation.3

Purpose

To evaluate the clinical and echocardiographic features of patients presenting with POS due to a cardiac cause.

Methods

We performed a retrospective analysis of patients diagnosed with POS in our centre between 2015 January and 2021 August. Routine blood tests and transthoracic echocardiogram (TTE) were performed in all patients. Demographics, clinical presentation, blood test results, TTE information, and PFO closure procedure details were recorded.

Results

Seven patients were included, 85.7% female (n = 6). The median (IQR) age was 78 (72-85) years. The most prevalent cardiovascular risk factors were hypertension (100%; n = 7) and overweight/obesity (85.7%; n = 6). Two patients (28.6%) had chronic pulmonary disease. The most common symptoms were fatigue and exercise intolerance (n= 5; 71.4%) and the most frequent sign was persistent hypoxemia (n = 7; 100%), although 28.6% (n = 2) patients did not present the typical positional changes in peripheral oxygen saturation. Haemoglobin levels [14.1 (13.3-15.2)] were within the normal range and serum NTproBNP levels [656 (287-1196)] were slightly elevated. Left ventricle function was preserved in all patients; right ventricle morphology and function were normal in 85.7% (n = 6) patients, low probability of pulmonary hypertension in TTE was found in 85.7% (n = 6), and exuberant Eustachian valve was observed in 14.3% (n = 1). All patients presented atrial septal hypermobility, 87.5% (n = 6) meeting atrial septal aneurysm criteria. Patent foramen ovale was found in 85.7% of patients (n = 6) and ostium secundum ASD in 14.3% (n = 1). POS precipitating factors were aortic root dilation (28.6%; n = 2), chest trauma (14.3%; n = 1), right hip arthroplasty (14.3%; n = 1), atrial septal stretching regarding right volume overload (14.3%; n = 1). The underlying mechanism was unknown in 28.6% (n = 2) of patients. ASD closure was performed in 57.1% (n = 4) of patients: 75% (n = 3) showed residual shunt, but clinical improvement was reported by all. No acute complications were described, except for paroxysmal atrial fibrillation (14.3%; n = 1).

Conclusion

POS diagnosis depends on high clinical suspicion: the most common manifestations are fatigue and persistent hypoxemia. Typical positional changes in oxygen saturation are not present in all patients. Polycythaemia, right chambers dilation, and pulmonary hypertension are not common. Echocardiography is fundamental for diagnosis, allowing right-to-left shunt confirmation and ASD morphology evaluation to outline a successful closure procedure.

Angiogenic response to passive movement and active exercise in individuals with peripheral arterial disease

Peripheral arterial disease (PAD) is caused by atherosclerosis and is associated with microcirculatory impairments in skeletal muscle. The present study evaluated the angiogenic response to exercise and passive movement in skeletal muscle of PAD patients compared with healthy control subjects. Twenty-one PAD patients and 17 aged control subjects were randomly assigned to either a passive movement or an active exercise study. Interstitial fluid microdialysate and tissue samples were obtained from the thigh skeletal muscle. Muscle dialysate vascular endothelial growth factor (VEGF) levels were modestly increased in response to either passive movement or active exercise in both subject groups. The basal muscle dialysate level of the angiostatic factor thrombospondin-1 protein was markedly higher (P < 0.05) in PAD patients compared with the control subjects, whereas soluble VEGF receptor-1 dialysate levels were similar in the two groups. The basal VEGF protein content in the muscle tissue samples was ∼27% lower (P < 0.05) in the PAD patients compared with the control subjects. Analysis of mRNA expression for a range of angiogenic and angiostatic factors revealed a modest change with active exercise and passive movement in both groups, except for an increase (P < 0.05) in the ratio of angiopoietin-2 to angiopoietin-1 mRNA in the PAD group with both interventions. PAD patients and aged individuals showed a similar limited angiogenic response to active exercise and passive movement. The limited increase in muscle extracellular VEGF combined with an elevated basal level of thrombospondin-1 in muscle extracellular fluid of PAD patients may restrict capillary growth in these patients.

Investigation of urinary volatile organic metabolites as potential cancer biomarkers by solid-phase microextraction in combination with gas chromatography-mass spectrometry

BACKGROUND

Non-invasive diagnostic strategies aimed at identifying biomarkers of cancer are of great interest for early cancer detection. Urine is potentially a rich source of volatile organic metabolites (VOMs) that can be used as potential cancer biomarkers. Our aim was to develop a generally reliable, rapid, sensitive, and robust analytical method for screening large numbers of urine samples, resulting in a broad spectrum of native VOMs, as a tool to evaluate the potential of these metabolites in the early diagnosis of cancer.

METHODS

To investigate urinary volatile metabolites as potential cancer biomarkers, urine samples from 33 cancer patients (oncological group: 14 leukaemia, 12 colorectal and 7 lymphoma) and 21 healthy (control group, cancer-free) individuals were qualitatively and quantitatively analysed. Dynamic solid-phase microextraction in headspace mode (dHS-SPME) using a carboxen-polydimethylsiloxane (CAR/PDMS) sorbent in combination with GC-qMS-based metabolomics was applied to isolate and identify the volatile metabolites. This method provides a potential non-invasive method for early cancer diagnosis as a first approach. To fulfil this objective, three important dHS-SPME experimental parameters that influence extraction efficiency (fibre coating, extraction time and temperature of sampling) were optimised using a univariate optimisation design. The highest extraction efficiency was obtained when sampling was performed at 50°C for 60 min using samples with high ionic strengths (17% sodium chloride, w v(-1)) and under agitation.

RESULTS

A total of 82 volatile metabolites belonging to distinct chemical classes were identified in the control and oncological groups. Benzene derivatives, terpenoids and phenols were the most common classes for the oncological group, whereas ketones and sulphur compounds were the main classes that were isolated from the urine headspace of healthy subjects. The results demonstrate that compound concentrations were dramatically different between cancer patients and healthy volunteers. The positive rates of 16 patients among the 82 identified were found to be statistically different (P<0.05). A significant increase in the peak area of 2-methyl-3-phenyl-2-propenal, p-cymene, anisole, 4-methyl-phenol and 1,2-dihydro-1,1,6-trimethyl-naphthalene in cancer patients was observed. On average, statistically significant lower abundances of dimethyl disulphide were found in cancer patients.

CONCLUSIONS

Gas chromatographic peak areas were submitted to multivariate analysis (principal component analysis and supervised linear discriminant analysis) to visualise clusters within cases and to detect the volatile metabolites that are able to differentiate cancer patients from healthy individuals. Very good discrimination within cancer groups and between cancer and control groups was achieved.

Efficacy and safety of cetuximab, oxaliplatin, and capecitabine as first-line therapy for metastatic colorectal cancer (mCRC): Results of a phase II study

e15013

Background: To date, few studies have investigated the use of cetuximab in combination with oxaliplatin and capecitabine in the first-line treatment of mCRC. We therefore conducted an uncontrolled, open-label, multicenter study to evaluate the efficacy and safety of this combination in this setting. Methods: Patients (pts) received intravenous (iv) oxaliplatin 130 mg/m2 (3h day 1) plus capecitabine 1,000 mg/m2 twice daily (days 1–14) every 3 weeks (XELOX) and cetuximab 400 mg/m2 iv week 1 then 250 mg/m2 weekly over 8 cycles. Treatment was continued until disease progression (PD), unacceptable toxicity or completion of therapy. Pts were followed until death. The primary endpoint was overall response rate (ORR). A sample size of 45 pts was necessary to obtain a 95% confidence interval (CI) for ORR with a maximum width of 15% assuming an ORR of 50–80%. Results: From Sept 2005-Jan 2007, 49 pts were enrolled (ITT population): 67% male, mean age 60 (range: 44–75) years, 56.3% ECOG PS 0. Of 42 pts evaluable for ORR, 4 (9.5%) achieved a complete response, 31 (73.8%) a partial response, 6 (14.3%) had stable disease and 1 (2.4%) had PD. The ORR was 83.3% (95% CI: 72.0–94.6%). Median time to progression was 9 months (95% CI: 7.1–10.9 months). Of the 49 pts evaluable for safety, 27 (55.1%) had at least one grade 3/4 toxicity, 42 (85.7%) had acne-like rash (8 pts [16.3%] grade 3). Most common grade 3/4 toxicities included diarrhea (n=9;18.4%) and changes in potassium (n=6;12.2%). 24 (3.4%) AEs led to dose reductions (12 unrelated, 10 unlikely and 2 definitely related to cetuximab), 56 (7.8%) led to a dose delay (12 unrelated, 28 unlikely, 8 possibly, 6 probably, 2 definitely related to cetuximab) and 2 (0.3%) led to infusion rate reduction (not treatment related). 27 (55.1%) pts discontinued therapy: 10 (20.4%) due to AEs, 7 (14.3%) PD, 10 (20.4%) other reasons. 33 (67.3%) pts died: 30 (61.2%) due to PD, 2 (4.1%) intercurrent event/disease, 1 (2.0%) acute pancreatitis. The results according with the HGFR evaluation by IHC will be presented. Conclusions: In this first-line mCRC study, 83.3% of pts treated with cetuximab, oxaliplatin and capecitabine achieved an overall response. This combination appears to be a highly active and well-tolerated regimen.

No significant financial relationships to disclose.

Disordered eating attitudes: an emerging health problem among Mediterranean adolescents

Aim of the present study was to investigate eating attitudes in a group of Mediterranean high school students. One hundred and twenty high school students participated in this survey. The Eating Attitudes Test (EAT-26) was used for evaluating symptoms and attitudes associated with disordered eating. Body composition and dietary intake were also assessed. Using the cut-off point of 20 in the total EAT, 13 females (20.3%) and 4 males (7.3%) exhibited disordered eating behavior. Overweight students had significantly higher scores in the dieting scale than those in the normal BMI range. Percent fat mass was positively related to the total EAT (r=0.326, p<0.001) and the dieting scale (r=0.489, p<0.001). Waist/hip ratio was negatively related to total EAT and its scales. In conclusion, a significant percentage of students in this urban Mediterranean adolescent population found to have abnormal eating attitudes. This finding may be partly explained by the effect of cultural transition.

Cassava starch maltodextrinization/monomerization through thermopressurized aqueous phosphoric acid hydrolysis

Kinetic conditions were established for the depolymerization of cassava starch for the production of maltodextrins and glucose syrups. Thin-layer chromatography and high-performance liquid chromatography analyses corroborated that the proper H3PO4 strength and thermopressurization range (e.g., 142-170 degrees C; 2.8-6.8 atm) can be successfully explored for such hydrolytic purposes of native starch granules. Because phosphoric acid can be advantageously maintained in the hydrolysate and generates, after controlled neutralization with ammonia, the strategic nutrient triplet for industrial fermentations (C, P, N), this pretreatment strategy can be easily recognized as a recommended technology for hydrolysis and upgrading of starch and other plant polysaccharides. Compared to the classic catalysts, the mandatory desalting step (chloride removal by expensive anion-exchange resin or sulfate precipitation as the calcium-insoluble salt) can be avoided. Furthermore, properly diluted phosphoric acid is well known as an allowable additive in several popular soft drinks such as colas since its acidic feeling in the mouth is compatible and synergistic with both natural and artificial sweeteners. Glycosyrups from phosphorolyzed cassava starch have also been upgraded to high-value single-cell protein such as the pigmented yeast biomass of Xanthophyllomyces dendrorhous (Phaffia rhodozyma), whose astaxanthin (diketo-dihydroxy-beta-carotene) content may reach 0.5-1.0 mg/g of dry yeast cell. This can be used as an ideal complement for animal feeding as well as a natural staining for both fish farming (meat) and poultry (eggs).