Anaemia and the heart

The worsening effect of anemia on left ventricular function and global strain in type 2 diabetes mellitus patients: a 3.0 T CMR feature tracking study

OBJECTIVE

To explore the additive effects of anemia on left ventricular (LV) global strains in patients with type 2 diabetes mellitus (T2DM) with or without anemia via cardiac magnetic resonance (CMR) feature tracking technology.

MATERIALS AND METHODS

236 T2DM patients with or without anemia and 67 controls who underwent CMR examination were retrospectively enrolled. LV function parameters, LV global radial peak strain (GRPS), longitudinal peak strain (GLPS), and circumferential peak strain (GCPS) were used to analyze the function and global strain of the heart. One-way analysis of variance and the chi-square test were used for intergroup analysis. Multivariable linear regression analysis was performed for the two T2DM groups to explore factors associated with LV global strains.

RESULTS

The T2DM group with anemia was oldest and had a lowest hemoglobin (Hb) concentration, lowest estimated glomerular filtration rate, highest LV end-systolic volume index, highest end-diastolic volume index and highest LV mass index than the control group and T2DM without anemia group (all P ≤ 0.001). Besides, The LV global peak strains in all three directions worsened successively from the control group to the T2DM without anemia group to the T2DM with anemia group (all p < 0.001). Among all clinical indices, the decrease in Hb was independently associated with the worsening in GRPS (β = 0.237, p = 0.001), GCPS (β = 0.326, p < 0.001), and GLPS (β = 0.265, p < 0.001).

CONCLUSION

Anemia has additive deleterious effects on LV function and LV global strains in patients with T2DM. Regular detection and early intervention of anemia might be beneficial for T2DM patients.

Differential impact of anemia in relation to sex in patients with myocardial infarction

Background

Data on the possible sex-specific effects of anemia on clinical outcome in patients with myocardial infarction are extremely sparse, conflicting, and inconclusive. We investigated the possible sex-specific effects of anemia on outcome in patients with myocardial infarction (MI) who underwent percutaneous coronary intervention (PCI).

Methods

Data from 8,318 patients, who were divided into four groups: men and women with and without anemia on admission, were analyzed. The association between anemia and sex and 30-day and long-term mortality was assessed. The median follow-up time was 7 years (25th, 75th percentile: 4, 11).

Results

Non-anemic men had the lowest 30-day and long-term observed mortality (4.3, 18.7%), followed by non-anemic women (7.0, 25.3%; p < 0.0001, p < 0.0001). Anemic men and women had similar mortality rates (12.8, 46.2%) and (13.4, 45.6%; p = 0.70, p = 0.80), respectively. The anemia/sex groups were independently associated with 30-day and long-term mortality (p = 0.033 and p < 0.0001, respectively). Compared to non-anemic men, non-anemic and anemic women had a similar risk of death at 30 days, but anemic men had a 50% higher risk of death (OR 1.12; 95% CI 0.83-1.52; p = 0.45, OR 1.30; 95% CI 0.94-1.79; p = 0.11, OR 1.50; 95% CI 1.13-1.98; p = 0.004, respectively). In the long term, anemic men had a 46% higher, non-anemic women 15% lower, and anemic women a similar long-term mortality risk to non-anemic men (HR 1.46; 95% CI 1.31-1.63; p < 0.0001, HR 0.85; 95% CI 0.76-0.96; p = 0.011, and HR 1.06; 95% CI 0.93-1.21; p = 0.37, respectively).

Conclusion

Our result suggests that the influence of anemia in patients with MI is different in men and women, with anemia seemingly much more harmful in male than in female patients with MI.

Treatment of high-output cardiac failure secondary to anemia in three cats

Case series summary

Three cats presented for clinical signs of respiratory distress and varying etiologies of anemia. Echocardiograms revealed evidence of cardiac dilation without other significant structural or functional heart disease. Thoracic imaging via point-of-care ultrasound and/or radiographs confirmed evidence of volume overload by pleural effusion. Each cat was diagnosed with presumed high-output cardiac failure secondary to anemia. Mainstays of treatment included controlling congestion and correcting the anemia with transfusions in the short-term while addressing the underlying etiology of the anemia in the long-term.

Relevance and novel information

Reports, treatment and management of high-output failure in the veterinary literature are limited. Extrapolating from human medicine, cats presenting with anemia and findings consistent with volume overload will benefit from treatment of their anemia to reduce neuroendocrine activation and the associated sodium and water retention. Therefore, blood transfusion should neither be avoided nor delayed in anemic cats with changes consistent with volume overload and congestive heart failure.

Exercise Oximetry Correlates Better With Exercise-Induced Lactate Increase, than Ankle Brachial Index or Walking Time, in Vascular Claudicants

In claudication, the correlation between walking-induced biomarkers and indices of clinical severity (e.g., walking distance or ankle brachial index (ABI)), is fair. We hypothesized that a correlation would be observed between the clinical estimation of ischemia severity with exercise transcutaneous oximetry (Ex-TcpO2) and lactate increase. A prospective study was performed among 377 patients with arterial claudication. We recorded age, sex, ABI, body mass index (BMI), systolic arterial blood pressure (SBP), and glycemia. Capillary blood lactate was measured at rest and 3 min after a constant load treadmill test. We recorded maximum walking time (MWT), heart rate (HRmax), the sum of minimal decrease from oxygen values for buttocks, thighs and calves Ex-TcpO2 (DROPmin), as well as the amplitude of chest-TcpO2 decrease. A multilinear regression model was used to assess the variables associated with lactate increase. BMI, SBP, HRmax, the amplitude of decrease in chest-TcpO2 and DROPmin, but not age, sex, ABI, MWT, diabetes mellitus nor glycemia, were significantly associated to lactate increase in the model. Because it accounts for the severity and diffusion of lower-limb exercise-induced ischemia and detects exercise induced hypoxemia, TcpO2 may be preferable to ABI or MWT to estimate the metabolic consequences of walking in claudicants.

Prospective payment system and racial/ethnic disparities: a national retrospective observational study in anaemia complication among end-stage renal disease patients in the US

Background

A series of policy changes in 2011 altered reimbursement arrangements and guidance on use of erythropoiesis-stimulating agents for end-stage renal disease (ESRD) patients with anaemia in the US. While the policy changes were principally directed at care delivered in an outpatient setting, these had the potential to affect inpatient care also. This study used HCUP-NIS data (2008–2016) to examine trends in recorded anaemia among ESRD hospitalizations and analyse disparities in inpatient outcomes among ethnic groups following policy changes.

Methods

The International Classification of Diseases codes were used to identify ESRD admissions, recorded anaemia due to chronic kidney disease (CKD), and to generate an age-adjusted Deyo-Charlson comorbidity index. Linear splines with a knot placed at the time point of policy changes and multivariable logistic regression were used to examine the likelihood of recorded anaemia, adjusted for a range of socio-demographic and clinical covariates. Difference-in-difference analyses investigated the impact of policies on recorded anaemia. Other outcomes included hospital cost, mortality and place of discharge.

Results

The percentage of inpatient episodes with recorded anaemia arising from CKD increased from 26.2% in 2008 to 50.0% in 2016. Anaemia was more likely to be recorded as a complication of ESRD among minority ethnic groups and Native American admissions, in particular, (OR 1.20, 95%CI 1.15–1.25) relative to White American admissions; and these disparities widened following changes to reimbursement. Minorities were less likely to die in hospital and to be discharged to another healthcare facility, and (with the exception of Black American admissions) they were more expensive to treat.

Conclusions

Our findings provide evidence of an increase in recorded anaemia consistent with a shift of patients from outpatient to inpatient settings in the wake of changes to reimbursement enacted in 2011. In addition, the study highlights the existence of ethnic disparities that widened after the policy initiated reimbursement changes.

Systematic review and meta-analysis: what is the evidence for oral iron supplementation in treating anaemia in elderly people?

BACKGROUND

Oral iron supplementation is used widely in older people despite observational studies suggesting it is ineffective.

OBJECTIVE

The aim of this systematic review was to determine if oral iron therapy is effective in elderly people with iron deficiency anaemia.

DATA SOURCES

MEDLINE, EMBASE and The Cochrane Library databases were searched from inception to 23 January 2014.

STUDY SELECTION

Randomised controlled trials comparing oral iron with no iron supplementation or placebo and measuring the change in haemoglobin levels in elderly patients with anaemia were included. Titles and abstracts were reviewed and publications were screened by both authors independently to exclude articles that did not satisfy the inclusion criteria.

STUDY APPRAISAL AND SYNTHESIS

Risk of bias was systematically assessed independently by both authors using the Cochrane risk of bias tool. Data on the increase in haemoglobin level after therapy was either collected from original publications or by contacting the corresponding authors. Length of hospitalisation, mortality and adverse effect data were also analysed.

RESULTS

A total of 6,163 citations were screened, but only three studies (a total of 440 participants with a mean age ranging between 70 and 83 years) met the inclusion criteria. Meta-analysis showed oral iron supplementation increased haemoglobin levels more than placebo or no treatment after 4-6 weeks of treatment (mean difference 0.35 g/dL, 95 % CI 0.12-0.59, p = 0.003). There were no statistically significant differences in adverse effects, length of hospitalisation or mortality.

LIMITATIONS

Only one of the three studies was specific to older people and all studies involved patients in orthopaedic settings. The mean age of participants was different, and the dosage and frequency of ferrous sulphate differed.

CONCLUSION

Oral iron raises haemoglobin levels in elderly people with iron deficiency anaemia by 0.35 g/dL after 4-6 weeks, but it is unclear if this results in tangible health benefits.

Does patient gender affect outcomes after concomitant coronary artery bypass graft and aortic valve replacement? An Australian Society of Cardiac and Thoracic Surgeons Database study

OBJECTIVES

Women undergoing isolated coronary artery bypass graft (CABG) surgery have been previously shown to be at an independently increased risk for post-operative morbidity and mortality. However, there are considerably less data on whether this trend remains true in patients undergoing concomitant aortic valve replacement (AVR) and CABG surgery. The aim of our study was to investigate this pertinent issue.

METHODS

Data obtained between June 2001 and December 2009 by the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database Program were retrospectively analysed. Demographic, operative data and post-operative complications were compared between male and female patients using χ(2) and t tests. Long-term survival analysis was performed using Kaplan-Meier survival curves and the log-rank test. Independent risk factors for short- and long-term mortality were identified using binary logistic and Cox regression, respectively.

RESULTS

Concomitant AVR and CABG surgery was undertaken in 2,563 patients; 31.8% were female. Female patients were older (mean age 76 vs. 73 years; p < 0.001) and presented more often with hypertension (p < 0.001) but less often with severely impaired ejection fraction (p < 0.001), peripheral vascular disease (p < 0.001) and triple vessel disease (p < 0.001). Women did not demonstrate an increased risk of 30-day mortality (4.8 vs. 3.3%) on univariate (p = 0.069) or multivariate (p = 0.236) analysis. Female gender was independently associated with post-operative myocardial infarction (p = 0.022) and red blood cell transfusion (p < 0.001). There was no difference in long-term survival between men and women on multivariate analysis (p = 0.413).

CONCLUSION

Female gender is not associated with poorer short- or long-term outcomes after concomitant CABG and AVR surgery.

Signs of left heart volume overload in severely anaemic cats

Anaemia induces haemodynamic compensatory mechanisms resulting in volume overload and increased left heart dimensions in humans and dogs. The aims of this retrospective study were to investigate the effects of anaemia on echocardiographic left heart dimensions, vertebral heart size (VHS) and radiographic evidence of congestive heart failure (CHF) in cats. Fifteen cats fulfilled the inclusion criteria and were classified as mildly anaemic (haematocrit (Hct)>18-24%) or severely anaemic (Hct≤18%). Eight out of eight severely anaemic cats had left atrial enlargement compared with 1/6 mildly anaemic cats (P<0.005) and severely anaemic cats also had a larger median left ventricular end-diastolic diameter (1.80cm versus 1.27cm, respectively; P<0.05). No difference was found between the groups in VHS or frequency of radiographic signs of CHF. Despite the small sample size, these preliminary findings suggest that severely anaemic cats are more likely to have enlarged left heart dimensions than mildly anaemic cats.

Ethnic differences in anemia among patients with diabetes mellitus: the Diabetes Study of Northern California (DISTANCE)

To examine ethnic differences in hemoglobin testing practices and to test the hypothesis that ethnicity is an independent predictor of anemia among patients with diabetes mellitus. We conducted a panel study to assess the rate of hemoglobin testing during 1999-2001 and the period prevalence and incidence of anemia among 79,985 adults with diabetes mellitus receiving care within Kaiser Permanente of Northern California. Anemia was defined as hemoglobin <13.0 g/dL in men or < 12.0 g/dL in women. Overall, 82.1% of the cohort was tested for anemia at least once during the 3-year study period. Mixed ethnicity patients were most likely to be tested, followed by whites, blacks, Latinos, and Asians (P < 0.0001). Fifteen percent of the cohort had prevalent anemia at baseline, and an additional 22% of those tested developed anemia during the study period. Anemia was more prevalent among blacks and mixed ethnicity persons compared with other racial/ethnic groups. Anemia was also more prevalent among those >/=70 years of age or with estimated glomerular filtration rate <60 ml/min/1.73 m(2). In multivariable models, blacks had higher and Asians had lower odds of prevalent anemia and hazard ratios of incident anemia compared with whites. Within a large, diverse cohort with diabetes, ethnicity was predictive of anemia, even after adjustment for age, level of kidney function, and other potential confounders. Blacks with diabetes are at increased risk of anemia relative to whites. These differences may account for some of the observed ethnic disparities in diabetes complications.

Predicting left ventricular remodeling after a first myocardial infarction by plasma proteome analysis

Recent improvements in therapeutic strategies did not prevent left ventricular remodeling (LVR), which remains a common event (30%) after acute myocardial infarction (AMI). We report the use of a systematic approach, based on comparative proteomics, to select circulating biomarkers that may be associated with LVR. We selected 93 patients enrolled in a prospective study. These patients with anterior wall Q-wave AMI underwent echocardiographic follow-up at hospitalization, 3 months and 1 year after AMI. They were divided into three groups (no, low, or high remodeling). Plasma samples of these patients (day 5 of hospitalization) were processed and stored at -80 degrees C within 2 h and analyzed using SELDI-TOF protein chip technology. This systematic approach allowed to select candidate proteins modulated by LVR: post-translational variants of alpha1-chain of haptoglobin (Hpalpha1) corresponding to m/z 9493, 9565, and 9623, which were more elevated in remodeling patients. The peak 9493 m/z was shown having a receiving-operating characteristic (ROC) value of 0.71 between non- and remodeling patients. SELDI-TOF approach may lead to the identification of circulating proteins associated with LVR. Whether these candidate proteins will help to identify patients who are at high risk of heart failure after AMI will have to be tested in future studies.

[Clinical determinants and prognostic value of hemoglobin in hospitalized patients with systolic heart failure]

INTRODUCTION AND OBJECTIVES

Anemia is a common finding in outpatients with heart failure (HF) and is associated with increased mortality. The aims of this study were to identify determinants of the hemoglobin level in a large group of hospitalized patients with systolic HF and to investigate the medium-term prognostic value of the hemoglobin level.

METHODS

The study included 460 consecutive patients (age 68.3 [12.3] years, 74% male) who were hospitalized with a diagnosis of HF and left ventricular systolic dysfunction (i.e., a left ventricular ejection fraction <45%). At hospital discharge, biochemical and hematological parameters were measured and clinical and echocardiographic variables were recorded. Patients were followed up for 16.8[9.7] months.

RESULTS

Anemia, as defined by World Health Organization criteria, was present in 189 (41.1%) patients. The following independent determinants of the hemoglobin level were identified: age (relative risk [RR]=1.035, 95% CI, 1.011-1.060; P=.004), female sex (RR=1.843, 95% CI, 1.083-3.135; P=.024), diabetes mellitus (RR=1.413, 95% CI, 1.087-1.838; P=.010), plasma urea level (RR=1.013, 95% CI, 1.005-1.022; P=.001), and loop diuretic use (RR=2.801, 95% CI, 1.463-5.364; P=.002). A decrease in hemoglobin level was associated with increased risks of death (RR per g/dL=1.232, 95% CI, 1.103-1.375; P<.001) and death or HF readmission (RR per g/dL=1.152, 95% CI, 1.058-1.255; P<.001), but not with readmission for non-fatal HF (RR per g/dL=1.081, 95% CI, 0.962-1.215; P=.265). Blood transfusion during hospitalization did not alter the increased risk of death (RR=2.19, 95% CI 1.40-3.41; P=.001).

CONCLUSIONS

In hospitalized patients with systolic HF, the hemoglobin level at hospital discharge was an independent predictor of death in the medium term, but not of readmission for non-fatal HF. The main determinants of the hemoglobin level were age, sex, renal function, diabetes, and the need for diuretics.

Anemia and morbidity and mortality in coronary bypass surgery

PURPOSE OF REVIEW

Anemia is associated with increased morbidity and mortality, in community-dwelling persons, in critically ill patients and perioperatively. The exact reasons and extent of the risks induced by anemia are not known, however, nor the optimal therapeutic approach. Based on the assumption that transfusion invariably counteracts the risks associated with perioperative anemia, most studies do not exclude the confounding effects of transfusion, and anemia is inconsistently defined. Cardiovascular disease was identified as a major additional risk for anemic patients, but the combined effects of decreasing hemoglobin and comorbidities in patients with coronary stenoses have not been determined exactly. This review integrates recent data to present a more differentiated understanding of mechanisms and risks of anemia in coronary artery bypass grafting surgery.

RECENT FINDINGS

Patients with many comorbidities are more susceptible to the effects of anemia. Some outcomes may primarily be caused by concomitant risk factors associated with anemia rather than by low hemoglobin per se. The precise interactions of anemia and comorbidities to produce worse outcomes are still unclear, as is the optimal therapeutic approach.

SUMMARY

The review highlights recent developments on anemia in heart surgery, and advocates new studies to institute individually adapted therapies.

Erythropoietin and the cardiorenal syndrome: cellular mechanisms on the cardiorenal connectors

We have recently proposed severe cardiorenal syndrome (SCRS), in which cardiac and renal failure mutually amplify progressive failure of both organs. This frequent pathophysiological condition has an extremely poor prognosis. Interactions between inflammation, the renin-angiotensin system, the balance between the nitric oxide and reactive oxygen species and the sympathetic nervous system form the cardiorenal connectors and are cornerstones in the pathophysiology of SCRS. An absolute deficit of erythropoietin (Epo) and decreased sensitivity to Epo in this syndrome both contribute to the development of anemia, which is more pronounced than renal anemia in the absence of heart failure. Besides expression on erythroid progenitor cells, Epo receptors are present in the heart, kidney, and vascular system, in which activation results in antiapoptosis, proliferation, and possibly antioxidation and anti-inflammation. Interestingly, Epo can improve cardiac and renal function. We have therefore reviewed the literature with respect to Epo and the cardiorenal connectors. Indeed, there are indications that Epo can diminish inflammation, reduce renin-angiotensin system activity, and shift the nitric oxide and reactive oxygen species balance toward nitric oxide. Information about Epo and the sympathetic nervous system is scarce. This analysis underscores the relevance of a further understanding of clinical and cellular mechanisms underlying protective effects of Epo, because this will support better treatment of SCRS.

Cardiac hypertrophy in anion exchanger 1-null mutant mice with severe hemolytic anemia

Anion exchanger 1 (AE1; SLC4A1), the plasma membrane Cl(-)/HCO(3)(-) exchanger of erythrocytes, is also expressed in heart. The aim of this study was to assess the role of AE1 in heart function through study of AE1-null (AE1(-/-)) mice, which manifest severe hemolytic anemia resulting from erythrocyte fragility. Heart weight-to-body weight ratios were significantly higher in the AE1(-/-) mice than in wild-type (AE1(+/+)) littermates at both 1-3 days postnatal (3.01 +/- 0.38 vs. 1.45 +/- 0.04) and at 7 days postnatal (9.45 +/- 0.53 vs. 4.13 +/- 0.41), indicating that loss of AE1 led to cardiac hypertrophy. Heterozygous (AE1(+/-)) mice had no signs of cardiac hypertrophy. Morphology of the adult AE1(-/-) mutant heart revealed an increased left ventricular mass, accompanied by increased collagen deposition and fibrosis. M-mode echocardiography revealed dysfunction of the AE1(-/-) hearts, including dilated left ventricle end diastole and systole and expanded left ventricular mass compared with AE1(+/+) hearts. Expression of intracellular pH-regulatory mechanisms in the hypertrophic myocardium of neonate AE1(-/-) mutant mice was indistinguishable from AE1(+/-) and AE1(+/+) mice, as assessed by quantitative real-time RT-PCR. Confocal immunofluorescence revealed that, in normal mouse myocardium, AE1 is sarcolemmal, whereas AE3 and slc26a6 are found both at the sarcolemma and in internal membranes (T tubules and sarcoplasmic reticulum). These results indicate that AE1(-/-) mice, which suffer from severe hemolytic anemia and spherocytosis, display cardiac hypertrophy and impaired cardiac function, reminiscent of findings in patients with hereditary abnormalities of red blood cells. No essential role for AE1 in heart function was found.