Differences in clinical outcomes, health care resource utilization and costs in heart failure patients according to left ventricular ejection fraction

INTRODUCTION AND OBJECTIVES

The impact of left ventricular ejection fraction (LVEF) on health care resource utilization (HCRU) and cost in heart failure (HF) patients is not well known. We aimed to compare outcomes, HCRUs and costs according to LVEF groups.

METHODS

Retrospective, observational study of all patients with an emergency department (ED) visit or admission to a tertiary hospital in Spain 2018 with a primary HF diagnosis. We excluded patients with newly diagnosed heart failure. One-year clinical outcomes, costs and HCRUs were compared according to LVEF (reduced [HFrEF], mildly reduced [HFmrEF], and preserved [HFpEF]).

RESULTS

Among 1287 patients with a primary diagnosis of HF in the ED, 365 (28.4%) were discharged to home (ED group), and 919 (71.4%) were hospitalized (hospital group [HG]). In total, 190 patients (14.7%) had HFrEF, 146 (11.4%) HFmrEF, and 951 (73.9%) HFpEF. The mean age was 80.1±10.7 years; 57.1% were female. The median [interquartile range] of costs per patient/y was €1889 [259-6269] in the ED group and €5008 [2747-9589] in the HG (P <.001). Hospitalization rates were higher in patients with HFrEF in the ED group. The median costs of HFrEF per patient/y were higher in patients in both groups: €4763 [2076-17 155] vs €3900 [590-8013] for HFmrEF vs €3812 [259-5486] for HFpEF in the ED group, and €6321 [3335-796] vs €6170 [3189-10484] vs €4636 [2609-8977], respectively, in the hospital group (all P <.001). This difference was driven by the more frequent admission to intensive care units, and greater use of diagnostic and therapeutic tests among HFrEF patients.

CONCLUSIONS

In HF, LVEF significantly impacts costs and HCRU. Costs were higher in patients with HFrEF, especially those requiring hospitalization, than in those with HFpEF.

Heart Failure in the Elderly: the Role of Biological and Sociocultural Aspects Related to Sex

PURPOSE OF REVIEW

Heart failure (HF) entails poor prognosis, with high morbidity and mortality burden, particularly in elderly patients. Notably, important sex differences have been described between men and women with HF. In this regard, some biological and sociocultural aspects related to sex may play a key role in the different development and prognosis of HF in elderly men and women.

RECENT FINDINGS

Important differences between men and women with HF, especially in the elderly population, have been specifically addressed in recent studies. Consequently, specific differences in biological and sociocultural aspects have been found to associate differences in pathophysiology, baseline clinical profile, and prognosis according to sex. Moreover, differences in comorbidities and frailty and other geriatric conditions, frequent in elderly population with HF, have also been described. Biological and sociocultural differences related to sex are key in the different clinical presentation and prognosis of heart failure in elderly women. Further studies will be required to better understand some other underlying reasons that may differently impact prognosis in elderly patients with HF.

Outcome of moderate-severe tricuspid regurgitation after pulmonary endarterectomy or balloon pulmonary angioplasty

INTRODUCTION AND OBJECTIVES

The management of persistent moderate-severe tricuspid regurgitation (TR) in patients with chronic thromboembolic pulmonary hypertension after treatment with pulmonary endarterectomy (PEA) or balloon pulmonary angioplasty (BPA) is not well defined. This study aimed to analyze the progression and predictors of significant persistent postintervention TR and its prognostic impact.

METHODS

This single-center observational study included 72 patients undergoing PEA and 20 who completed a BPA program with a previous diagnosis of chronic thromboembolic pulmonary hypertension and moderate-to-severe TR.

RESULTS

The postintervention prevalence of moderate-to-severe TR was 29%, with no difference between the PEA- or BPA-treated groups (30.6% vs 25% P=.78). Compared with patients with absent-mild postprocedure TR, those with persistent TR had higher mean pulmonary arterial pressure (40.2±1.9 vs 28.5±1.3mmHg P <.001), pulmonary vascular resistance (472 [347-710] vs 282 [196-408] dyn.s/cm5; P <.001), and right atrial area (23.0 [21-31] vs 16.0 [14.0-20.0] P <.001). The variables independently associated with persistent TR were pulmonary vascular resistance> 400 dyn.s/cm5 and postprocedure right atrial area> 22cm2. No preintervention predictors were identified. The variables associated with increased 3-year mortality were residual TR and mean pulmonary arterial pressure> 30mmHg.

CONCLUSIONS

Residual moderate-to-severe TR following PEA-PBA was associated with persistently high afterload and unfavorable postintervention right chamber remodeling. Moderate-to-severe TR and residual pulmonary hypertension were associated with a worse 3-year prognosis.

Early Detection and Progression of Subclinical Atherosclerosis in Psoriasis (EDSAP): protocol for an observational, single-centre, prospective cohort study

INTRODUCTION

Life expectancy of patients with psoriasis is reduced by 4-5 years due to cardiovascular disease with an increased risk of myocardial infarction at an earlier age compared with the general population. This increased risk is independent of traditional cardiovascular risk factors and higher in moderate-to-severe forms of psoriasis. Inflammation may play a key role in the development of atherosclerosis in these patients.

METHODS AND ANALYSIS

A prospective cohort study, Early Detection and Progression of Subclinical Atherosclerosis in Psoriasis (EDSAP), was initiated in January 2020 to investigate the presence and progression of subclinical atherosclerosis in patients with psoriasis. 120 patients aged 30-65 years and eligible for biological treatment have been recruited at Hospital Ramón y Cajal in Madrid, Spain. Patients undergo a baseline visit, and 1-year follow-up visit after starting biological therapy. Each visit includes: assessment of cardiovascular risk factors, screening for subclinical atherosclerosis by two-dimensional/three-dimensional ultrasound of carotid and femoral arteries, cardiac CT of coronary arteries and blood sampling. All baseline visits were completed by December 2022, and the remaining follow-up visits will be concluded by the end of 2023. The EDSAP study aims to identify new molecular and imaging markers associated with the presence of atherosclerosis and its progression in a chronic inflammatory state such as psoriasis. This has the potential to: (1) help improve primary cardiovascular prevention strategies in these patients; (2) understand the effect of biological drugs on the cardiovascular system; and (3) serve as a model for understanding atherosclerosis in other chronic inflammatory diseases.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Institutional Review Board of the Hospital Ramón y Cajal in Madrid. We will present our findings at national and international congresses, and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05858099.

Cardiovascular and renal health: Preeclampsia as a risk marker

BACKGROUND

Cardiovascular (CVD) and chronic kidney disease (CKD) in women have unique risk factors related to hormonal status and obstetric history that must be taken into account. Pregnancy complications, such as preeclampsia (PE), can reveal a subclinical predisposition for the development of future disease that may help identify women who could benefit from early CVD and CKD prevention strategies.

MATERIALS AND METHODS

Review of PE and its association with future development of CVD and CKD.

RESULTS

Multiple studies have established an association between PE and the development of ischemic heart disease, chronic hypertension, peripheral vascular disease, stroke and CKD. It has not been sufficiently clarified if this relation is a causal one or if it is mediated by common risk factors. Nevertheless, the presence of endothelial dysfunction and thrombotic microangiopathy during pregnancies complicated with PE makes us believe that PE may leave a long-term imprint. Early identification of women who have had a pregnancy complicated by PE becomes a window of opportunity to improve women's health through adequate follow-up and targeted preventive actions. Oxidative stress biomarkers and vascular ultrasound may play a key role in the early detection of this arterial damage.

CONCLUSIONS

The implementation of preventive multidisciplinary targeted strategies can help slow down CVD and CKD's natural history in women at risk through lifestyle modifications and adequate blood pressure control. Therefore, we propose a series of recommendations to guide the prediction and prevention of CVD and CKD throughout life of women with a history of PE.

From Double-Chambered Right Ventricle to Double-Chambered Left Ventricle: Unusual Evolution of a Ventricular Septal Defect

We present the first imaging registry of the progressive isolation of an apical chamber of the right ventricle caused by the hypertrophy of the moderator band generated from the hemodynamic effect of a ventricular septal defect, leaving the apex of the right ventricle as an accessory chamber of the left ventricle. (Level of Difficulty: Advanced.).

Early detection of anthracycline- and trastuzumab-induced cardiotoxicity: value and optimal timing of serum biomarkers and echocardiographic parameters

AIMS

To evaluate echocardiographic and biomarker changes during chemotherapy, assess their ability to early detect and predict cardiotoxicity and to define the best time for their evaluation.

METHODS AND RESULTS

Seventy-two women with breast cancer (52 ± 9.8 years) treated with anthracyclines (26 also with trastuzumab), were evaluated for 14 months (6 echocardiograms/12 laboratory tests). We analysed: high-sensitivity cardiac troponin T, NT-proBNP, global longitudinal strain (GLS), left ventricle end-systolic volume (LVESV), left ventricle end-diastolic volume (LVEDV), and left ventricular ejection fraction (LVEF). Cardiotoxicity was defined as a reduction in LVEF>10% compared with baseline with LVEF<53%. High-sensitivity troponin T levels rose gradually reaching a maximum peak at 96 ± 13 days after starting chemotherapy (P < 0.001) and 62.5% of patients presented increased values during treatment. NT-proBNP augmented after each anthracycline cycle (mean pre-cycle levels of 72 ± 68 pg/mL and post-cycle levels of 260 ± 187 pg/mL; P < 0.0001). Cardiotoxicity was detected in 9.7% of patients (mean onset at 5.2 months). In the group with cardiotoxicity, the LVESV was higher compared with those without cardiotoxicity (40 mL vs. 29.5 mL; P = 0.045) at 1 month post-anthracycline treatment and the decline in GLS was more pronounced (-17.6% vs. -21.4%; P = 0.03). Trastuzumab did not alter serum biomarkers, but it was associated with an increase in LVESV and LVEDV (P < 0.05). While baseline LVEF was an independent predictor of later cardiotoxicity (P = 0.039), LVESV and GLS resulted to be early detectors of cardiotoxicity [odds ratio = 1.12 (1.02-1.24), odds ratio = 0.66 (0.44-0.92), P < 0.05] at 1 month post-anthracycline treatment. Neither high-sensitivity troponin T nor NT-proBNP was capable of predicting subsequent cardiotoxicity.

CONCLUSIONS

One month after completion of anthracycline treatment is the optimal time to detect cardiotoxicity by means of imaging parameters (LVESV and GSL) and to determine maximal troponin rise. Baseline LVEF was a predictor of later cardiotoxicity. Trastuzumab therapy does not affect troponin values hence imaging techniques are recommended to detect trastuzumab-induced cardiotoxicity.

The anti-aging factor Klotho protects against acquired long QT syndrome induced by uremia and promoted by fibroblast growth factor 23

BACKGROUND

Chronic kidney disease (CKD) is associated with increased propensity for arrhythmias. In this context, ventricular repolarization alterations have been shown to predispose to fatal arrhythmias and sudden cardiac death. Between mineral bone disturbances in CKD patients, increased fibroblast growth factor (FGF) 23 and decreased Klotho are emerging as important effectors of cardiovascular disease. However, the relationship between imbalanced FGF23-Klotho axis and the development of cardiac arrhythmias in CKD remains unknown.

METHODS

We carried out a translational approach to study the relationship between the FGF23-Klotho signaling axis and acquired long QT syndrome in CKD-associated uremia. FGF23 levels and cardiac repolarization dynamics were analyzed in patients with dialysis-dependent CKD and in uremic mouse models of 5/6 nephrectomy (Nfx) and Klotho deficiency (hypomorphism), which show very high systemic FGF23 levels.

RESULTS

Patients in the top quartile of FGF23 levels had a higher occurrence of very long QT intervals (> 490 ms) than peers in the lowest quartile. Experimentally, FGF23 induced QT prolongation in healthy mice. Similarly, alterations in cardiac repolarization and QT prolongation were observed in Nfx mice and in Klotho hypomorphic mice. QT prolongation in Nfx mice was explained by a significant decrease in the fast transient outward potassium (K⁺) current (I_tof), caused by the downregulation of K⁺ channel 4.2 subunit (Kv4.2) expression. Kv4.2 expression was also significantly reduced in ventricular cardiomyocytes exposed to FGF23. Enhancing Klotho availability prevented both long QT prolongation and reduced I_tof current. Likewise, administration of recombinant Klotho blocked the downregulation of Kv4.2 expression in Nfx mice and in FGF23-exposed cardiomyocytes.

CONCLUSION

The FGF23-Klotho axis emerges as a new therapeutic target to prevent acquired long QT syndrome in uremia by minimizing the predisposition to potentially fatal ventricular arrhythmias and sudden cardiac death in patients with CKD.

Mitral valve prolapse morphofunctional features by cardiovascular magnetic resonance: more than just a valvular disease

INTRODUCTION

Mitral valve (MV) prolapse (MVP) is a primary valvular abnormality. We hypothesized that additionally there are concomitant abnormalities of the left ventricle (LV) and MV apparatus in this entity even in the absence of significant mitral regurgitation (MR).

OBJECTIVE

To characterize MV and LV anatomic and functional features in MVP with preserved LV ejection fraction, with and without significant MR, using cardiovascular magnetic resonance (CMR).

METHODS

Consecutive MVP patients (n = 80, mean 52 years, 37% males) with preserved LV ejection fraction, and 44 controls (46 years, 52% males) by CMR were included, as well as 13 additional patients with "borderline" MVP. From cine images we quantified LV volumes, MV and LV anatomic measurements (including angle between diastolic and systolic annular planes, annular displacement, and basal inferolateral hypertrophy) and, using feature tracking, longitudinal and circumferential peak systolic strains.

RESULTS

Significant MR was found in 46 (56%) MVP patients. Compared with controls, MVP patients had LV enlargement, basal inferolateral hypertrophy, higher posterior annular excursion, and reduced shortening of the papillary muscles. LV basal strains were significantly increased, particularly in several basal segments. These differences remained significant in patients without significant MR, and many persisted in "borderline" MVP.

CONCLUSIONS

In patients with MVP and preserved LV ejection fraction there is LV dilatation, basal inferolateral hypertrophy, exaggerated posterior annular displacement and increased basal deformation, even in the absence of significant MR or overt MVP. These findings suggest that MVP is a disease not only of the MV but also of the adjacent myocardium.

Frequency and Prognosis of Treated Hypertensive Patients According to Prior and New Blood Pressure Goals

United States and European guidelines have recommended new treatment goals for office blood pressure (BP). We examined 9784 hypertensives of the Spanish Ambulatory BP Monitoring (ABPM) registry with office BP treated to the prior goal (<140/90 mm Hg); and evaluated the frequency and all-cause mortality of 4 BP strata depending on whether or not they attained more conservative or new office BP goal (130-139/80-89 and <130/80 mm Hg, respectively) and whether or not BP was controlled according to ABPM criteria in the European and US guidelines (24-hour ambulatory BP <130/80 and <125/75 mm Hg, respectively). Whether achieving or not the new office BP goal, the total-mortality risk during a 5-year follow-up was only significantly higher than the reference (normal office BP and ABPM) when 24-hour ambulatory BP was above goal (hazard ratio from multivariable Cox models was in the range of 2.4-2.9; P<0.001). The frequency of patients achieving the new office BP goal was 34.4%, and the frequencies of those not achieving the ABPM goal were 31.6% and 53.7% using the 130/80 or the 125/75 ABPM goal, respectively. Mean office systolic BP was 129 mm Hg for patients not achieving the ABPM goal. In hypertensive patients controlled under prior office BP goal, the frequency of those achieving new office BP goal <130/80 was high, suggesting this goal can be attained. In addition, patients had a higher mortality risk only when ABPM was above goal despite having mean office systolic BP under control, a condition that was also common.

Fibroblast growth factor-23 promotes rhythm alterations and contractile dysfunction in adult ventricular cardiomyocytes

Background

Cardiac dysfunction and arrhythmia are common and onerous cardiovascular events in end-stage renal disease (ESRD) patients, especially those on dialysis. Fibroblast growth factor (FGF)-23 is a phosphate-regulating hormone whose levels dramatically increase as renal function declines. Beyond its role in phosphorus homeostasis, FGF-23 may elicit a direct effect on the heart. Whether FGF-23 modulates ventricular cardiac rhythm is unknown, prompting us to study its role on excitation–contraction (EC) coupling.

Methods

We examined FGF-23 in vitro actions on EC coupling in adult rat native ventricular cardiomyocytes using patch clamp and confocal microscopy and in vivo actions on cardiac rhythm using electrocardiogram.

Results

Compared with vehicle treatment, FGF-23 induced a significant decrease in rat cardiomyocyte contraction, L-type Ca2+ current, systolic Ca2+ transients and sarcoplasmic reticulum (SR) load and SR Ca2+-adenosine triphosphatase 2a pump activity. FGF-23 induced pro-arrhythmogenic activity in vitro and in vivo as automatic cardiomyocyte extracontractions and premature ventricular contractions. Diastolic spontaneous Ca2+ leak (sparks and waves) was significantly increased by FGF-23 via the calmodulin kinase type II (CaMKII)-dependent pathway related to hyperphosphorylation of ryanodine receptors at the CaMKII site Ser2814. Both contraction dysfunction and spontaneous pro-arrhythmic Ca2+ events induced by FGF-23 were blocked by soluble Klotho (sKlotho).

Conclusions

Our results show that FGF-23 reduces contractility and enhances arrhythmogenicity through intracellular Ca2+ mishandling. Blocking its actions on the heart by improving sKlotho bioavailability may enhance cardiac function and reduce arrhythmic events frequently observed in ESRD.

Mechanistic insights of the left ventricle structure and fibrosis in the arrhythmogenic mitral valve prolapse

Mitral valve prolapse (MVP) is a common and benign condition. However, some anatomic forms have been recently associated with life-threatening ventricular arrhythmias and sudden cardiac death. Imaging MVP holds the promise of individualized MVP risk assessment. Noninvasive imaging techniques available today are playing an increasingly important role in the diagnosis, prognosis and monitoring of MVP. In this article, we will review the current evidence on arrhythmogenic MVP, with special focus on the utility of echocardiography and CMR for identifying benign and "malignant" forms of MVP. The clinical relevance of this manuscript lies in the value of imaging technology to improve MVP risk prediction, including those arrhythmic-MVP cases with a higher risk of sudden cardiac death.

In-frame Variants in FLNA Proximal Rod 1 Domain Associate With a Predominant Cardiac Valvular Phenotype

INTRODUCTION AND OBJECTIVES

X-linked cardiac valvular dysplasia is a rare form of male-specific congenital heart defect mainly characterized by myxomatous degeneration of the atrioventricular valves with variable hemodynamic consequences. It is caused by genetic defects in FLNA-encoded filamin A, a widely expressed actin-binding protein that regulates cytoskeleton organization. Filamin A loss of function has also been associated with often concurring neurologic and connective tissue manifestations, with mutations in the first half of the Rod 1 domain apparently expressing the full cardiac phenotype. We contribute to previous genotype-phenotype correlations with a multidisciplinary approach in a newly-described family.

METHODS

Cardiologic, dysmorphologic, and genetic evaluation of available members were complemented with transcriptional and X-chromosome inactivation studies.

RESULTS

A novel FLNA mutation c.1066-3C>G cosegregated with a male-expressed, apparently isolated, cardiac phenotype with no skewed X-inactivation pattern in female carriers. This variant was shown to result in an in-frame deletion of 8 amino acid residues near the N-terminal region of the protein.

CONCLUSIONS

A nonimprinted, partial loss of function of filamin A proximal Rod 1 domain seems to be the pathogenetic mechanism of cardiac valvular dysplasia, with some cases occasionally expressing associated extracardiac manifestations.

Current concepts in diagnosis and perioperative management of carcinoid heart disease

Carcinoid tumors are neuroendocrine tumors with a very unpredictable clinical behavior. In the setting of hepatic metastases, the tumor's release of bioactive substances into the systemic circulation results in carcinoid syndrome: a constellation of symptoms among which cutaneous flushing, gastrointestinal hypermotility, and cardiac involvement are the most prominent. Cardiac manifestations, also known as carcinoid heart disease, are secondary to a severe fibrotic reaction which frequently involves the right-sided valves and may extend towards the subvalvular apparatus leading to valve thickening and retraction. Left-sided involvement is rare and mostly observed in the presence of an interatrial shunt, endobronchial tumor localization, and high tumor activity. Echocardiographic techniques often reveal noncoaptation of the valves, which are fixed in a semiopen position. In patients with advanced lesions and severe valvular dysfunction, surgery is currently the only definitive treatment to potentially improve quality of life and provide survival benefit. Although cardiac surgery has been traditionally reserved for those patients with symptomatic right ventricular failure, a significant trend towards improved surgical outcomes has triggered a more liberal referral for valve replacement. Carcinoid heart disease poses two distinct challenges for the anesthesiologist: carcinoid crisis and low cardiac output syndrome secondary to right ventricular failure. Carcinoid crisis, characterized by flushing, hypotension, and bronchospasm, may be precipitated by catecholamines and histamine releasing drugs used routinely in patients undergoing valve surgery. Although a broader utilization of octreotide have significantly simplified the anesthetic and perioperative management of these patients, a very balanced anesthetic technique is required to identify and manage low cardiac output syndrome.

[Optimized transseptal approach for left ventricular tachycardia ablation in a patient with a mechanical prosthetic aortic valve]

Prosthetic valves may make ventricular access difficult in radiofrequency catheter ablation. This case report describes an optimized atrial transseptal approach to access the ventricle in a patient with left ventricular tachycardia and a mechanical prosthetic aortic valve.

Selective identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of different types of gluten in foods made with cereal mixtures

The gluten toxic fractions responsible for the mucosal damage in coeliac disease (CD), so-called gliadins, hordeins, secalins and avenins from a large number (30-40) of wheat, barley, rye and oats cultivars respectively, have been mass analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Gliadin, secalin and avenin characteristic mass profiles are nearly identical amongst distinct cultivars from the corresponding cereal, while hordeins profiles show more variability depending on the particular barley cultivar. On the basis of these four distinguishable characteristic mass patterns spreading within the 20,000-40,000 Da range, MALDI-TOF-MS has permitted the direct and simultaneous visualization of gliadins, hordeins, secalins and avenins in foods elaborated with cereal mixtures of wheat, barley, rye and oats. This capacity has been demonstrated by mass analyzing foods made with these four cereals in varying ratios. Thus MALDI-TOF-MS can be preliminarily established as a unique system with the ability to discriminate the specific type of gluten toxic fractions present in food samples.

Massive glycation of protein HC, a low molecular weight lipocalin, in non-diabetic individuals

Human protein HC is a member of the lipocalin superfamily with unique properties since it carries a covalently bound fluorescent chromophore mediating the linkage of the major part of protein HC to several plasma proteins, with IgA as the dominating complex partner. Native protein HC displays characteristic absorption and fluorescence spectra similar to those of glycated proteins with advanced glycosylation end products (AGEs). In vitro glycation of protein HC induces the formation of fibril aggregates with a corresponding increase of absorption in the visible region of the spectrum. Boronate-affinity chromatography and a novel galactosyltransferase assay indicate that protein HC is modified with residues of glucose exposed in a terminal non-reducing position which is typical of glycated proteins. The glycation level of several isolated batches of protein HC as measured by both assays was around 35%, which represents the highest level described for human plasma-derived proteins from healthy individuals.

[Chylothorax as presenting form of a gastric adenocarcinoma]

Malignancies other than lymphoma can in rare instances induce the development of chylothorax. A patient with this unusual type of pleural effusion is described herein. The need to rule out a gastric neoplasm when confronted with a case of chylothorax with no obvious cause is stressed.

[Cerebrovascular accident in young adults. A study of 52 cases]

OBJECTIVE

A retrospective study of ischaemic and haemorrhagic cerebral vascular accidents in patients under 45 years of age, admitted to hospital Severo Ochoa (Area sanitaria 9 de la Comunidad de Madrid) during a 6 year period.

METHOD

23 CVAs in women and 29 in men were studied. The aetiology of each episode was determined following preestablished criteria.

RESULTS

Aetiology: cardiac 13 (25%), atherosclerosis: 8 (15%), haematological: 6 (11%), non-atherosclerotic: 8 (15%), migraine: 1 (2%), hypertensive: 2 (3%), unknown: 15 (29%). There was a predominance of men in the patients with atherosclerosis. These also had more cardiovascular risk factors and were older than the other patients. All patients with CVA due to antiphospholipid antibodies had multiple CVAs. Examinations used to establish the aetiology were: echocardiogram, angiography, carotid doppler, hypercoagulability studies and the clinical history.

CONCLUSIONS

In spite of extensive study, 30% of the CVAs in young people still have no aetiological diagnosis. In general in ischaemic CVAs, there is good recovery of the neurological defects and a low mortality. The detection and oral anticoagulation of patients with a source of cardiac emboli, and the elimination of cardiovascular risk factors would probably considerably reduce the incidence of ischaemic stroke in young adults.

Studies on the oxidation-reduction systems of the erythrocyte

1. Starvation for 3 days produces a decrease in methaemoglobin-reductase and glutathione-reductase activities, but it does not alter the glucose 6-phosphate-dehydrogenase activity of the rat erythrocyte. 2. The feeding of a protein-free diet for 11 days causes greater changes in the first two enzymes and also a diminution of the third. Under this experimental condition slight decreases in protein and haemoglobin contents were noted. 3. The experimental animals did not show methaemoglobinaemia, probably because the activity of methaemoglobin diaphorase is preserved. 4. The GSH content was not affected but the stability of the tripeptide in the presence of an oxidizing agent was diminished.