Omecamtiv mecarbil treatment improves post-resuscitation cardiac function and neurological outcome in a rat model

Background

Myocardial dysfunction is a major cause of poor outcomes in the post-cardiac arrest period. Omecamtiv mecarbil (OM) is a selective small molecule activator of cardiac myosin that prolongs myocardial systole and increases stroke volume without apparent effects on myocardial oxygen demand. OM administration is safe and improves cardiac function in patients with acute heart failure. Whether OM improves post-resuscitation myocardial dysfunction remains unclear. This study investigated the effect of OM treatment on post-resuscitation myocardial dysfunction and outcomes.

Methods and results

Adult male rats were resuscitated after 9.5 min of asphyxia-induced cardiac arrest. OM and normal saline was continuously intravenously infused after return of spontaneous circulation (ROSC) at 0.25 mg/kg/h for 4 h in the experimental group and control group, respectively (n = 20 in each group). Hemodynamic parameters were measured hourly and monitored for 4 h after cardiac arrest. Recovery of neurological function was evaluated by neurological functioning scores (0–12; favorable: 11–12) for rats 72 h after cardiac arrest. OM treatment prolonged left ventricular ejection time and improved post-resuscitation cardiac output. Post-resuscitation heart rate and left ventricular systolic function (dp/dt₄₀) were not different between groups. Kaplan-Meier analysis showed non-statistically higher 72-h survival in the OM group (72.2% [13/18] and 58.8% [10/17], p = 0.386). The OM group had a higher chance of having favorable neurological outcomes in surviving rats 72 h after cardiac arrest (84.6% [11/13] vs. 40% [4/10], p = 0.026). The percentage of damaged neurons was lower in the OM group in a histology study at 72 h after cardiac arrest (55.5±2.3% vs. 76.2±10.2%, p = 0.004).

Conclusions

OM treatment improved post-resuscitation myocardial dysfunction and neurological outcome in an animal model. These findings support further pre-clinical studies to improve outcomes in post-cardiac arrest care.

Ventricular Dysfunction in Obese and Nonobese Rats with Metabolic Syndrome

Obesity and dyslipidemias are both signs of metabolic syndrome, usually associated with ventricular arrhythmias. Here, we tried to identify cardiac electrical alteration and biomarkers in nonobese rats with metabolic syndrome (MetS), and these findings might lead to more lethal arrhythmias than obese animals. The MetS model was developed in Wistar rats with high-sucrose diet (20%), and after twenty-eight weeks were obtained two subgroups: obese (OMetS) and nonobese (NOMetS). The electrocardiogram was used to measure the ventricular arrhythmias and changes in the heart rate variability. Also, we measured ventricular hypertrophy and its relationship with electrical activity alterations of both ventricles, using micro-electrode and voltage clamp techniques. Also, we observed alterations in the contraction force of ventricles where a transducer was used to record mechanical and electrical papillary muscle, simultaneously. Despite both subgroups presenting long QT syndrome (0.66 ± 0.05 and 0.66 ± 0.07 ms with respect to the control 0.55 ± 0.1 ms), the changes in the heart rate variability were present only in OMetS, while the NOMetS subgroup presented changes in QT interval variability (NOMetS SD = 1.8, SD2 = 2.8; SD1/SD2 = 0.75). Also, the NOMetS revealed tachycardia (10%; p < 0.05) with changes in action potential duration (63% in the right papillary and 50% in the left papillary) in the ventricular papillary which are correlated with certain alterations in the potassium currents and the force of contraction. The OMetS showed an increase in action potential duration and the force of contraction in both ventricles, which are explained as bradycardia. Our results revealed lethal arrhythmias in both MetS subgroups, irrespectively of the presence of obesity. Consequently, the NOMetS showed mechanical-electrical alterations regarding ventricle hypertrophy that should be at the NOMetS, leading to an increase of CV mortality.

Trauma, a Matter of the Heart-Molecular Mechanism of Post-Traumatic Cardiac Dysfunction

Trauma remains a leading global cause of mortality, particularly in the young population. In the United States, approximately 30,000 patients with blunt cardiac trauma were recorded annually. Cardiac damage is a predictor for poor outcome after multiple trauma, with a poor prognosis and prolonged in-hospitalization. Systemic elevation of cardiac troponins was correlated with survival, injury severity score, and catecholamine consumption of patients after multiple trauma. The clinical features of the so-called "commotio cordis" are dysrhythmias, including ventricular fibrillation and sudden cardiac arrest as well as wall motion disorders. In trauma patients with inappropriate hypotension and inadequate response to fluid resuscitation, cardiac injury should be considered. Therefore, a combination of echocardiography (ECG) measurements, echocardiography, and systemic appearance of cardiomyocyte damage markers such as troponin appears to be an appropriate diagnostic approach to detect cardiac dysfunction after trauma. However, the mechanisms of post-traumatic cardiac dysfunction are still actively being investigated. This review aims to discuss cardiac damage following trauma, focusing on mechanisms of post-traumatic cardiac dysfunction associated with inflammation and complement activation. Herein, a causal relationship of cardiac dysfunction to traumatic brain injury, blunt chest trauma, multiple trauma, burn injury, psychosocial stress, fracture, and hemorrhagic shock are illustrated and therapeutic options are discussed.

Cardiomyocyte Oga haploinsufficiency increases O-GlcNAcylation but hastens ventricular dysfunction following myocardial infarction

Rationale

The beta-O-linkage of N-acetylglucosamine (i.e., O-GlcNAc) to proteins is a pro-adaptive response to cellular insults. To this end, increased protein O-GlcNAcylation improves short-term survival of cardiomyocytes subjected to acute injury. This observation has been repeated by multiple groups and in multiple models; however, whether increased protein O-GlcNAcylation plays a beneficial role in more chronic settings remains an open question.

Objective

Here, we queried whether increasing levels of cardiac protein O-GlcNAcylation would be beneficial during infarct-induced heart failure.

Methods and results

To achieve increased protein O-GlcNAcylation, we targeted Oga, the gene responsible for removing O-GlcNAc from proteins. Here, we generated mice with cardiomyocyte-restricted, tamoxifen-inducible haploinsufficient Oga gene. In the absence of infarction, we observed a slight reduction in ejection fraction in Oga deficient mice. Overall, Oga reduction had no major impact on ventricular function. In additional cohorts, mice of both sexes and both genotypes were subjected to infarct-induced heart failure and followed for up to four weeks, during which time cardiac function was assessed via echocardiography. Contrary to our prediction, the Oga deficient mice exhibited exacerbated—not improved—cardiac function at one week following infarction. When the observation was extended to 4 wk post-MI, this acute exacerbation was lost.

Conclusions

The present findings, coupled with our previous work, suggest that altering the ability of cardiomyocytes to either add or remove O-GlcNAc modifications to proteins exacerbates early infarct-induced heart failure. We speculate that more nuanced approaches to regulating O-GlcNAcylation are needed to understand its role—and, in particular, the possibility of cycling, in the pathophysiology of the failing heart.

Role of TSPO/VDAC1 Upregulation and Matrix Metalloproteinase-2 Localization in the Dysfunctional Myocardium of Hyperglycaemic Rats

Clinical management of diabetic cardiomyopathy represents an unmet need owing to insufficient knowledge about the molecular mechanisms underlying the dysfunctional heart. The aim of this work is to better clarify the role of matrix metalloproteinase 2 (MMP-2) isoforms and of translocator protein (TSPO)/voltage-dependent anion-selective channel 1 (VDAC1) modulation in the development of hyperglycaemia-induced myocardial injury. Hyperglycaemia was induced in Sprague-Dawley rats through a streptozocin injection (35 mg/Kg, i.p.). After 60 days, cardiac function was analysed by echocardiography. Nicotinamide Adenine Dinucleotide Phosphate NADPH oxidase and TSPO expression was assessed by immunohistochemistry. MMP-2 activity was detected by zymography. Superoxide anion production was estimated by MitoSOX™ staining. Voltage-dependent anion-selective channel 1 (VDAC-1), B-cell lymphoma 2 (Bcl-2), and cytochrome C expression was assessed by Western blot. Hyperglycaemic rats displayed cardiac dysfunction; this response was characterized by an overexpression of NADPH oxidase, accompanied by an increase of superoxide anion production. Under hyperglycaemia, increased expression of TSPO and VDAC1 was detected. MMP-2 downregulated activity occurred under hyperglycemia and this profile of activation was accompanied by the translocation of intracellular N-terminal truncated isoform of MMP-2 (NT-MMP-2) from mitochondria-associated membrane (MAM) into mitochondria. In the onset of diabetic cardiomyopathy, mitochondrial impairment in cardiomyocytes is characterized by the dysregulation of the different MMP-2 isoforms. This can imply the generation of a “frail” myocardial tissue unable to adapt itself to stress.

Impact of delayed ventricular wall area ratio on pathophysiology of mechanical dyssynchrony: implication from single-ventricle physiology and 0D modeling

Electrical disparity can induce inefficient cardiac performance, representing an uncoordinated wall motion at an earlier activated ventricular wall: an early shortening followed by a systolic rebound stretch. Although regional contractility and distensibility modulate this pathological motion, the effect of a morphological factor has not been emphasized. Our strain analysis in 62 patients with single ventricle revealed that those with an activation delay in 60-70% of ventricular wall area suffered from cardiac dysfunction and mechanical discoordination along with prolonged QRS duration. A computational simulation with a two-compartment ventricular model also suggested that the ventricle with an activation delay in 70% of the total volume was most vulnerable to a large activation delay, accompanied by an uncoordinated motion at an earlier activated wall. Taken together, the ratio of the delayed ventricular wall has a significant impact on the pathophysiology due to an activation delay, potentially highlighting an indicator of cardiac dysfunction.

Maternal cardiac function in gestational diabetes mellitus at 35-36 weeks' gestation and 6 months postpartum

OBJECTIVE

Women with gestational diabetes mellitus (GDM) are at increased risk for adverse cardiovascular outcome later in life. However, it is uncertain whether this increased risk is due to cardiovascular changes occurring during pregnancy and persisting thereafter or to an adverse underlying cardiovascular risk factor profile. Some studies have reported that GDM is associated with reduced systolic and diastolic left ventricular function in pregnancy; however, it remains unknown whether these changes persist after delivery. The objective of this study was to compare cardiac function and structure in women with GDM and those with uncomplicated pregnancy at 35-36 weeks' gestation and about 6 months after delivery.

METHODS

This was a longitudinal study in which women with GDM and those with uncomplicated pregnancy had detailed cardiovascular assessment at 35-36 weeks' gestation and repeat examination around 6 months after delivery. In all women, left ventricular systolic and diastolic indices were measured and left ventricular mass indexed for body surface area was calculated. Cardiac output and peripheral vascular resistance were also calculated using echocardiography. Linear mixed model analysis accounting for differences in maternal characteristics was carried out to compare findings of cardiovascular function between the GDM group and controls and within each group at 35-36 weeks' gestation and at 6 months after delivery.

RESULTS

We studied 73 women with GDM and 73 controls with uncomplicated pregnancy. At 35-36 weeks' gestation, women with GDM, compared to controls, had higher E/e' ratio and lower E/A ratio and global longitudinal systolic strain; there were no significant differences between the groups in ejection fraction. Left ventricular mass indexed for body surface area was also increased in women with GDM. There were no significant differences between the groups in cardiac output and peripheral vascular resistance. At 6 months after delivery, cardiac functional indices improved in both patients with GDM and controls, but in the GDM group, compared to controls, there was a lower degree of improvement in E/A ratio and global longitudinal systolic strain.

CONCLUSION

In the third trimester, patients with GDM have subtle differences in diastolic and systolic left ventricular function compared to controls and, despite improvement after delivery, these changes persist for at least 6 months. Long-term follow-up is therefore needed to assess whether women with GDM are at risk for an accelerated decline in their cardiac function and, if so, whether this trend can be reversed or delayed by optimal cardiovascular risk factor modification. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Impact of gestational diabetes mellitus on maternal cardiac adaptation to pregnancy

OBJECTIVE

To determine whether maternal cardiac adaptation at term differs between women with, and those without, gestational diabetes mellitus (GDM).

METHODS

This was a prospective case-control study of pregnant women at term with or without GDM. For both cases and controls, only women without any comorbidity or form of pre-existing diabetes who had a singleton pregnancy without complication (such as pre-eclampsia or fetal growth restriction) were included. All women underwent conventional and speckle-tracking echocardiography to assess both the left- and right-heart geometry and function.

RESULTS

A total of 40 women with GDM and 40 healthy controls were enrolled. Women with GDM, compared with controls, had a significantly higher heart rate (83 ± 10 vs 75 ± 9 beats per min; P < 0.001), left ventricular (LV) relative wall thickness (0.43 ± 0.07 vs 0.37 ± 0.08; P < 0.001), LV early diastolic transmitral valve velocity (E) (0.80 ± 0.15 vs 0.73 ± 0.12 m/s; P = 0.026) and LV late diastolic transmitral valve velocity (A) (0.65 ± 0.13 vs 0.57 ± 0.11 m/s; P = 0.006). In women with GDM compared with controls, speckle-tracking analysis revealed a significant reduction in LV global longitudinal strain (GLS) (-16.29 ± 2.26 vs -17.61 ± 1.89; P = 0.012), LV endocardial GLS (-18.50 ± 2.59 vs -19.84 ± 2.35; P = 0.031) and LV epicardial GLS (-14.40 ± 2.01 vs -15.73 ± 1.66; P = 0.005). Right ventricular (RV) analysis revealed a reduced pulmonary acceleration time (58 ± 10 vs 66 ± 11 ms; P = 0.001) and RV E/A ratio (1.13 ± 0.18 vs 1.29 ± 0.35; P = 0.017), as well as a higher RV myocardial systolic annular velocity (0.16 ± 0.04 vs 0.14 ± 0.02; P = 0.023) and peak late diastolic transtricuspid valve velocity (0.46 ± 0.1 m/s vs 0.39 ± 0.08 m/s; P = 0.001), in women with GDM compared to controls.

CONCLUSIONS

Our findings show that even a short period of exposure to hyperglycemia, as occcurs in women with GDM, is associated with significant maternal functional cardiac impairment at term. Given these findings, further study of postnatal maternal cardiovascular recovery after GDM pregnancy is warranted. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Influence of early extensive posterior decompression on hyponatremia and cardiopulmonary dysfunction after severe traumatic cervical spinal cord injury: A clinical observational study

Retrospective single institution observational study.The aim of the present study was to analyze the influence of early extensive posterior decompression on complications in patients with severe traumatic cervical spinal cord injury (tcSCI).Cervical SCI is associated with a high prevalence of hyponatremia and cardiopulmonary dysfunction. However, very few studies have focused on this exploration to reduce the incidence of SCI early complications.We reviewed the medical records of consecutive patients undergoing extensive posterior decompression within 24 h for severe tcSCI (American Spinal Injury Association Impairment Scale [AIS] A to C) admitted between January 2009 and January 2018. The data collected retrospectively included age, gender, mechanism, and level of SCI, AIS grade, fracture or dislocation, electrolyte, and cardiopulmonary complications.Of the 97 enrolled patients, the baseline AIS grade was AIS A in 14, AIS B in 31, and AIS C in 52. Improvement of at least two AIS grades was found in 26 (26.8%), and improvement of at least one grade was found in 80.4% of patients at discharge. Twenty-nine (29.9%) patients had mild hyponatremia, 8 (8.2%) had moderate hyponatremia, and 3 (3.1%) had severe hyponatremia during hospitalization. The incidences of hyponatremia, hypotension, and tracheotomy were 41.2%, 13.4%, and 6.2%, respectively. The mean forced vital capacity (FVC) on admission and at discharge was 1.34 ± 0.46 L and 2.21 ± 0.41 L (P < .0001), respectively. Five patients developed pneumonia.Our results suggest that early expansive posterior decompression significantly reduces the incidence of hyponatremia, hypotension, and tracheotomy by promoting recovery of spinal cord function after severe tcSCI.

The Heart and COVID-19: What Cardiologists Need to Know

In face of the pandemic of the novel coronavirus disease 2019 (COVID-19), the management of patients with cardiovascular risk factors and/or disease is challenging. The cardiovascular complications evidenced in patients with COVID-19 derive from several mechanisms, ranging from direct viral injury to complications secondary to the inflammatory and thrombotic responses to the infection. The proper care of patients with COVID-19 requires special attention to the cardiovascular system aimed at better outcomes.

Perinatal changes in fetal cardiac geometry and function in diabetic pregnancy at term

OBJECTIVE

To evaluate the effect of diabetes in pregnancy on fetal and neonatal cardiac geometry and function around the time of delivery.

METHODS

This was a prospective study of 75 pregnant women delivering at term, comprising 54 normal pregnancies and 21 with a diagnosis of pregestational or gestational diabetes mellitus. Fetal and neonatal conventional and spectral tissue Doppler and two-dimensional speckle-tracking echocardiography were performed a few days before and within hours after delivery. Fetal and neonatal cardiac geometry, global myocardial deformation and performance, diastolic and systolic function and left ventricular (LV) torsion were compared between normal pregnancies and those with diabetes, and perinatal changes within the diabetes group were assessed.

RESULTS

Compared with normal pregnancies, diabetic pregnancies demonstrated significant differences in fetal ventricular geometry, myocardial deformation and cardiac function (right ventricular (RV) sphericity index, 0.56 vs 0.65; LV torsion, 2.1 °/cm vs 5.6 °/cm; LV isovolumetric relaxation time, 101 ms vs 115 ms; and RV isovolumetric contraction time, 107 ms vs 119 ms; P < 0.001 for all). Compared with normal pregnancies, diabetic pregnancies demonstrated significant differences in neonatal cardiac parameters (mean RV sphericity index, 0.43 vs 0.55; mean LV torsion, 1.30 °/cm vs 2.78 °/cm; median LV myocardial performance index (MPI'), 0.39 vs 0.51; median RV-MPI', 0.34 vs 0.40; P < 0.01 for all). Paired comparison between fetal and neonatal cardiac indices in diabetic pregnancies demonstrated that delivery resulted in a significant improvement in some, but not all, cardiac indices (mean RV sphericity index, 0.65 vs 0.55; mean LV torsion, 5.60 °/cm vs 2.78 °/cm; median RV-MPI', 0.51 vs 0.40; P < 0.01 for all).

CONCLUSIONS

Compared with normal term fetuses and neonates, those of diabetic women exhibit cardiac indices indicative of myocardial impairment, reflecting a response to a relatively hyperglycemic intrauterine environment with alteration in fetal loading conditions (LV preload deprivation and increased RV afterload) and adaptation to subsequent acute changes in hemodynamic load at delivery. Elucidating mechanisms that contribute to the alterations in perinatal cardiac function in diabetic pregnancy could help in refining management and developing better therapeutic strategies to reduce the risk of adverse pregnancy outcomes. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Nocturnal ventricular arrhythmias are associated with the severity of cardiovascular autonomic neuropathy in type 2 diabetes

BACKGROUND

Cardiovascular autonomic neuropathy (CAN) is a risk factor for arrhythmias and adverse cardiovascular events, but the relationship between CAN severity and nocturnal arrhythmias needs to be clarified. This study evaluated the association between nocturnal arrhythmias and CAN severity in patients with type 2 diabetes (T2D).

METHODS

In all, 219 T2D patients were recruited from January 2017 to May 2018. Subjects were classified into no CAN (NCAN), early CAN (ECAN), definite CAN (DCAN), or advanced CAN (ACAN) based on cardiovascular autonomic reflex tests (CARTs). A 24-hour electrocardiogram was recorded and daytime (0700-2300 hours) and night-time (2300-0700 hours) heartbeats were analyzed separately.

RESULTS

After adjusting for age, the incidence of ventricular arrhythmias increased with CAN severity at night-time (18.6%, 29.9%, 36.2%, and 60.0% in the NCAN, ECAN, DCAN, and ACAN groups, respectively; P_trend  = 0.034). Patients with nocturnal ventricular arrhythmias (NVAs) had higher CART scores (2.0 ± 1.0 vs 1.5 ± 0.9; P < 0.001) and lower heart rate variability (HRV) during deep breathing (9.5 ± 5.7 vs 11.6 ± 6.6 b. p. m; P = 0.021), HRV during the Valsalva maneuver (1.2 ± 0.1 vs 1.2 ± 0.2; P = 0.006), and postural blood pressure change (-8.8 ± 15.5 vs -4.1 ± 11.2 mmHg; P = 0.023). Multivariate regression analysis revealed that CAN stage (odds ratio 1.765; 95% confidence interval 1.184-2.632; P = 0.005) was independently associated with NVAs.

CONCLUSIONS

In T2D, CAN stage was independently associated with the presence of NVAs. Early detection, diagnosis, and treatment of CAN may help predict and prevent adverse cardiovascular events and cardiovascular mortality in diabetes.

Changes in left and right ventricular two-dimensional echocardiographic speckle-tracking indices in pediatric LVAD population: A retrospective clinical study

Echocardiographic strain and strain-rate imaging is a promising tool for the evaluation of myocardial segmental function, for the early detection of myocardial dysfunction, and for the prediction of reverse remodeling. We aimed at studying the changes in left and right ventricular function in pulsatile left ventricular assist device pediatric patients by two-dimensional echocardiography and two-dimensional speckle-tracking echocardiography. Echocardiographic and clinical data of patients implanted with a pulsatile-flow left ventricular assist device from 2011 to 2018 were retrospectively reviewed before and after implantation at 1, 3, and 6 months. A total of 18 patients were enrolled. Median age and weight at implantation were 9 months (5-23 months) and 5.85 kg (4.85-8.75 kg), respectively; median left ventricular assist device support was 181 (114.5-289.5) days. 13 patients (73%) were transplanted and 5 patients (27%) died. At follow-up: left ventricular ejection fraction increase at 1 month (p = 0.001) and 3 months (p = 0.01), left ventricular global longitudinal strain improvement at 1 month (p = 0.0008) and 3 months (p = 0.02), and right ventricular free-wall longitudinal strain increase at 1 month (p = 0.01). At short term after left ventricular assist device implantation, both left ventricular and right ventricular mechanics improved. The temporary benefit seems to decrease over time. The worsening of left ventricular function has been followed by a worsening of right ventricular function probably due to the ventricular interdependence.

Effects of AT1 receptor antagonism on interstitial and ultrastructural remodeling of heart in response to a hypercaloric diet

Palatable hypercaloric feeding has been associated with angiotensin-II type 1 receptor (AT1R) stimulation and cardiac remodeling. This study analyzed whether AT1R antagonism attenuates cardiac remodeling in rats subjected to a palatable hypercaloric diet. Male Wistar-Kyoto rats were subjected to a commercial standard rat chow (CD) or a palatable hypercaloric diet (HD) for 35 weeks and then allocated into four groups: CD, CL, HD, and HL; L groups received losartan in drinking water (30 mg/kg/day) for 5 weeks. Body weight, adiposity, and glycemia were evaluated. The cardiovascular study included echocardiography, and myocardial morphometric and ultrastructural evaluation. Myocardial collagen isoforms Type I and III were analyzed by Western blot. Both HD and HL had higher adiposity than their respective controls. Cardiomyocyte cross-sectional-area (CD 285 ± 49; HD 344 ± 91; CL 327 ± 49; HL 303 ± 49 μm2 ) and interstitial collagen fractional area were significantly higher in HD than CD and unchanged by losartan. HD showed marked ultrastructural alterations such as myofilament loss, and severe mitochondrial swelling. CL presented higher Type I collagen expression when compared to CD and HL groups. The ultrastructural changes and type I collagen expression were attenuated by losartan in HL. Losartan attenuates systolic dysfunction and ultrastructural abnormalities without changing myocardial interstitial remodeling in rats subjected to a palatable hypercaloric diet.

Does Levetiracetam Administration Prevent Cardiac Damage in Adulthood Rats Following Neonatal Hypoxia/Ischemia-Induced Brain Injury?

Cardiovascular abnormalities are widespread when a newborn is exposed to a hypoxic-ischemic injury in the neonatal period. Although the neuroprotective effects of levetiracetam (LEV) have been reported after hypoxia, the cardioprotective effects of LEV have not been documented. Therefore, we aimed to investigate whether levetiracetam (LEV) has a protective effect on cardiac-contractility and ultrastructure of heart muscle in rats exposed to hypoxia-ischemia (HI) during the neonatal period. A total of 49 seven-day-old rat pups were separated into four groups. For HI induction, a combination of right common carotid artery ligation with 8% oxygen in seven-day-old rat pups for 2 h was performed for saline, LEV100, and LEV200 groups. Just after hypoxia, LEV100 and LEV200 groups were administered with 100 mg/kg and 200 mg/kg of LEV, respectively. The arteries of rats in the control group were only detected; no ligation or hypoxia was performed. At the end of the 16th week after HI, cardiac mechanograms were recorded, and samples of tissue were explored by electronmicroscopy.While ventricular contractility in the control group was similar to LEV100, there were significant decreases in both saline and LEV200 groups (p < 0.05). Although ventricular contractile duration of the control and saline groups was found to be similar, durations in the LEV100 and LEV200 groups were significantly higher (p < 0.05). After HI, mitochondrial damage and ultrastructural deteriorative alterations in ventricles and atriums of the LEV-administered groups were significantly less severe than the saline group. The present study showed that neonatal HI caused long-term cardiac dysfunction and ultrastructural deteriorations in cardiac muscles. LEV administration just after HI might possess some protective effects against myocardial damage and contractility.

High-Fat-Diet-Induced Obesity Produces Spontaneous Ventricular Arrhythmias and Increases the Activity of Ryanodine Receptors in Mice

Ventricular arrhythmias are a common cause of sudden cardiac death, and their occurrence is higher in obese subjects. Abnormal gating of ryanodine receptors (RyR2), the calcium release channels of the sarcoplasmic reticulum, can produce ventricular arrhythmias. Since obesity promotes oxidative stress and RyR2 are redox-sensitive channels, we investigated whether the RyR2 activity was altered in obese mice. Mice fed a high fat diet (HFD) became obese after eight weeks and exhibited a significant increase in the occurrence of ventricular arrhythmias. Single RyR2 channels isolated from the hearts of obese mice were more active in planar bilayers than those isolated from the hearts of the control mice. At the molecular level, RyR2 channels from HFD-fed mice had substantially fewer free thiol residues, suggesting that redox modifications were responsible for the higher activity. Apocynin, provided in the drinking water, completely prevented the appearance of ventricular arrhythmias in HFD-fed mice, and normalized the activity and content of the free thiol residues of the protein. HFD increased the expression of NOX4, an isoform of NADPH oxidase, in the heart. Our results suggest that HFD increases the activity of RyR2 channels via a redox-dependent mechanism, favoring the appearance of ventricular arrhythmias.

Treatment with Fenofibrate plus a low dose of Benznidazole attenuates cardiac dysfunction in experimental Chagas disease

Trypanosoma cruzi induces serious cardiac alterations during the chronic infection. Intense inflammatory response observed from the beginning of infection, is critical for the control of parasite proliferation and evolution of Chagas disease. Peroxisome proliferator-activated receptors (PPAR)-α, are known to modulate inflammation. In this study we investigated whether a PPAR-α agonist, Fenofibrate, improves cardiac function and inflammatory parameters in a murine model of T. cruzi infection. BALB/c mice were sequentially infected with two T. cruzi strains of different genetic background. Benznidazole, commonly used as trypanocidal drug, cleared parasites but did not preclude cardiac pathology, resembling what is found in human chronic chagasic cardiomyopathy. Fenofibrate treatment restored to normal values the ejection and shortening fractions, left ventricular end-diastolic, left ventricular end-systolic diameter, and isovolumic relaxation time. Moreover, it reduced cardiac inflammation and fibrosis, decreased the expression of pro-inflammatory (IL-6, TNF-α and NOS2) and heart remodeling mediators (MMP-9 and CTGF), and reduced serum creatine kinase activity. The fact that Fenofibrate partially inhibited NOS2 expression and NO release in the presence of a PPAR-α non-competitive inhibitor, suggested it also acted through PPAR-α-independent pathways. Since IκBα cytosolic degradation was inhibited by Fenofibrate, it can be concluded that the NFκB pathway has a role in its effects. Thus, we demonstrate that Fenofibrate acts through PPAR-α-dependent and -independent pathways. Our study shows that combined treatment with Fenofibrate plus Benznidazole is able both to reverse the cardiac dysfunction associated with the ongoing inflammatory response and fibrosis and to attain parasite clearance in an experimental model of Chagas disease.

Effect of sodium-glucose co-transporter-2 inhibitors on impaired ventricular repolarization in people with Type 2 diabetes

AIMS

To test the hypothesis that treatment with a sodium-glucose co-transporter-2 inhibitor would reverse ventricular repolarization heterogeneity, a predictor of cardiovascular mortality, in people with Type 2 diabetes.

METHODS

We retrospectively analysed changes in indices of ventricular repolarization before and after treatment with a sodium-glucose co-transporter-2 inhibitor in 46 people with Type 2 diabetes.

RESULTS

Sodium-glucose co-transporter-2 inhibitor treatment reduced HbA_1c concentration [62±13 mmol/mol (7.7±1.2%) vs 59±16 mmol/mol (7.5±1.4%)], body weight (77.8±13.9 vs 74.7±12.5 kg) and systolic blood pressure (133±18 vs 126±12 mmHg) in the study participants. Heart rate and QTc interval were not changed by sodium-glucose co-transporter-2 inhibitor treatment, but QTc dispersion was significantly reduced (median, 48.8 vs 44.2 ms). Sodium-glucose co-transporter-2 inhibitor treatment reversed QTc dispersion more in participants who had larger QTc dispersion before the treatment. Changes in systolic blood pressure (Spearman's ρ= 0.319; P=0.031), but not in HbA_1c concentration, were correlated with changes in QTc dispersion after sodium-glucose co-transporter-2 inhibitor treatment.

CONCLUSIONS

The findings suggest that sodium-glucose co-transporter-2 inhibitor treatment reverses ventricular repolarization heterogeneity in people with Type 2 diabetes, independently of its effect on glycaemic control. The favourable effect on ventricular repolarization heterogeneity could be the mechanism by which empaglifozin reduced cardiovascular events in a recent study.

Prevalence of Diastolic Dysfunction in Type 2 Diabetes Mellitus

Background Diastolic dysfunction is an inability of the ventricle to fill to a normal end-diastolic volume, both during exercise as well as at rest. Diabetes mellitus increases the risk of heart failure even in the absence of other co-morbidities. Objective To find the prevalence of diastolic dysfunction in patients with type 2 diabetes mellitus and its association with age, gender, duration, glycosylated hemoglobin levels, dyslipidemia, tobacco smoking and alcohol consumption. Method Ninety patients with type 2 diabetes mellitus of both genders, aged 30 to 60 years, were included in this study. Doppler echocardiography was performed to evaluate diastolic dysfunction. Result The mean age of the study population was 46.21 ± 9.20 yrs. The overall prevalence of diastolic dysfunction in the study population was 47.8%. The prevalence of diastolic dysfunction increases with age: 23.1% in patients of age 30 - 39 yrs to 65.8% in patients of age 50 - 60 yrs (adjusted OR 0.16, 95% CI 0.04 - 0.64, P = 0.010) and with the duration of diabetes: 32.8% in patients with diabetes for <5 yrs to 75% in patients with diabetes for >10 yrs (adjusted OR 0.31, 95% CI 0.08 - 1.00, P = 0.05). There was no significant association between diastolic dysfunction and dyslipidaemia, BMI, tobacco smoking, alcohol consumption, HbA1c and gender. Conclusion Prevalence of diastolic dysfunction in type 2 diabetes mellitus was 47.8% in our study. A rising trend of prevalence of diastolic dysfunction with the duration of diabetes and increasing age of patients was observed.

N-Acetylcysteine Prevents Low T3 Syndrome and Attenuates Cardiac Dysfunction in a Male Rat Model of Myocardial Infarction

Nonthyroidal illness syndrome (NTIS) affects patients with myocardial infarction (MI). Oxidative stress has been implicated as a causative factor of NTIS, and reversed via N-acetylcysteine (NAC). Male Wistar rats submitted to left anterior coronary artery occlusion received NAC or placebo. Decreases in triiodothyronine (T3) levels were noted in MI-placebo at 10 and 28 days post-MI, but not in MI-NAC. Groups exhibited similar infarct areas whereas MI-NAC exhibited higher ejection fraction than did MI-placebo. Left ventricular systolic and diastolic diameters were also preserved in MI-NAC, but not in MI-placebo. Ejection fraction was positively correlated with T3 levels. Oxidative balance was deranged only in MI-placebo animals. Increased type 3 iodothyronine deiodinase expression was detected in the cardiomyocytes of MI-placebo compared with normal heart tissue. NAC was shown to diminish type 3 iodothyronine deiodinase expression and activity in MI-NAC. These results show that restoring redox balance by NAC treatment prevents NTIS- related thyroid hormone derangement and preserves heart function in rats subjected to MI.

Utility of transthoracic echocardiography (TTE) in assessing fluid responsiveness in critically ill patients - a challenge for the bedside sonographer

Transthoracic echocardiography (TTE) has become one of the most important diagnostic tools in the treatment of critically ill patients. It allows clinicians to recognise potentially reversible life-threatening situations and is also very effective in the monitoring of the fluid status of patients, slowly substituting invasive methods in the intensive care unit. Hemodynamic assessment is based on a few static and dynamic parameters. Dynamic parameters change during the respiratory cycle in mechanical ventilation and the level of this change directly corresponds to fluid responsiveness. Most of the parameters cannot be used in spontaneously breathing patients. For these patients the most important test is passive leg raising, which is a good substitute for fluid bolus. Although TTE is very useful in the critical care setting, we should not forget the important limitations, not only technical ones but also caused by the critical illness itself. Unfortunately, this method does not allow continuous monitoring and every change in the patient's condition requires repeated examination.

Sickle Cell Disease with Cyanotic Congenital Heart Disease: Long-Term Outcomes in 5 Children

Sickle cell disease is a risk factor for cerebrovascular accidents in the pediatric population. This risk is compounded by hypoxemia. Cyanotic congenital heart disease can expose patients to prolonged hypoxemia. To our knowledge, the long-term outcome of patients who have combined sickle cell and cyanotic congenital heart disease has not been reported. We retrospectively reviewed patient records at our institution and identified 5 patients (3 girls and 2 boys) who had both conditions. Their outcomes were uniformly poor: 4 died (age range, 12 mo-17 yr); 3 had documented cerebrovascular accidents; and 3 developed ventricular dysfunction. The surviving patient had developmental delays. On the basis of this series, we suggest mitigating hypoxemia, and thus the risk of stroke, in patients who have sickle cell disease and cyanotic congenital heart disease. Potential therapies include chronic blood transfusions, hydroxyurea, earlier surgical correction to reduce the duration of hypoxemia, and heart or bone marrow transplantation.

Multi-Country Evaluation of Safety of Dihydroartemisinin/Piperaquine Post-Licensure in African Public Hospitals with Electrocardiograms

The antimalarial drug piperaquine is associated with delayed ventricular depolarization, causing prolonged QT interval (time taken for ventricular de-polarisation and re-polarisation). There is a lack of safety data regarding dihydroartemisinin/piperaquine (DHA/PPQ) for the treatment of uncomplicated malaria, which has limited its use. We created a platform where electrocardiograms (ECG) were performed in public hospitals for the safety assessment of DHA/PPQ, at baseline before the use of dihydroartemisinin/piperaquine (Eurartesim^®), and on day 3 (before and after administration of the final dose) and day 7 post-administration. Laboratory analyses included haematology and clinical chemistry. The main objective of the ECG assessment in this study was to evaluate the effect of administration of DHA/PPQ on QTc intervals and the association of QTc intervals with changes in blood biochemistry, full and differential blood count over time after the DHA/PPQ administration. A total of 1315 patients gave consent and were enrolled of which 1147 (87%) had complete information for analyses. Of the enrolled patients 488 (42%), 323 (28%), 213 (19%) and 123 (11%) were from Ghana, Burkina Faso, Tanzania and Mozambique, respectively. Median (lower—upper quartile) age was 8 (5–14) years and a quarter of the patients were children under five years of age (n = 287). Changes in blood biochemistry, full and differential blood count were temporal which remained within clinical thresholds and did not require any intervention. The mean QTcF values were significantly higher than on day 1 when measured on day 3 before and after administration of the treatment as well as on day 7, four days after completion of treatment (12, 22 and 4 higher, p < 0.001). In all age groups the values of QT, QTcF and QTcB were highest on day 3 after drug intake. The mean extreme QTcF prolongation from baseline was lowest on day 3 before drug intake (33 ms, SD = 19) and highest on day 3 after the last dose (60 ms, SD = 31). There were 79 (7%) events of extreme mean QTcF prolongation which were not clinically significant. Nearly a half of them (n = 37) were grade 3 and mainly among males (33/37). Patients in Burkina Faso, Mozambique and Tanzania had significantly lower mean QTcF than patients in Ghana by an average of 3, 4 and 11 ms, respectively. We found no evidence that Eurartesim^® administered in therapeutic doses in patients with uncomplicated malaria and no predisposing cardiac conditions in Africa was associated with adverse clinically significant QTc prolongation.

Acute Fulminant Myocarditis after Diphtheria, Polio, and Tetanus Vaccination

We report an infant case of acute fulminant myocarditis which occurred after administration of a diphtheria, polio, and tetanus vaccination. Fever and dyspnea developed after the vaccination. Extracorporeal membrane oxygenation was used for intractable cardiogenic shock. The patient survived the extracorporeal support, but poor ventricular contractility recurred 2 months later and she died while waiting for heart transplantation.

Increased serum gamma-glutamyltransferase levels are associated with ventricular instability in type 2 diabetes

The purpose of our study is to examine the association between serum GGT levels and ventricular instability in Chinese patients with T2DM. We conducted a cross-sectional, community-based study in Nanjing, China from June to November 2011. Among 10,050 patients aged 40-79 years, we enrolled 2444 with pre-diabetes, 2496 with T2DM, and 4521 without diabetes (non-diabetes). Electrocardiograms were performed to measure the QT interval corrected for heart rate (QTc) and QT interval dispersion (QTd). Serum GGT levels, metabolic parameters, body mass index, and blood pressure were also measured. We found that there were no significant associations of increased QTc/QTd with serum GGT levels in participants with pre-existing T2DM and non-diabetes, after adjusting for age, duration of diabetes, and metabolic parameters. Even after adjustment, higher risks of QTc ≥ 440 ms/√s and QTd ≥ 58 ms were found in participants with serum GGT levels ≥49 U/L compared with those with <15 U/L in the pre-diabetes (QTc: OR 1.96, 95 % CI 1.23-2.47; QTd: OR 1.34, 95 % CI 1.07-1.94) and newly diagnosed T2DM (QTc: OR 2.01, 95 % CI 1.39-2.51; QTd: OR 1.53, 95 % CI 1.03-1.99) groups. We conclude that Increased serum GGT levels are associated with some markers of ventricular repolarization abnormalities in the early stage of T2DM.

Biventricular Myocardial Performance Is Impaired in Proportion to Severity of Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular morbidity and death. Little information is available regarding the relationship between the severity of OSA and myocardial performance in OSA patients who have normal ejection fractions. We prospectively investigated this relationship, using the tissue-Doppler myocardial performance index (TD-MPI). We conducted overnight, full-laboratory polysomnographic examinations of 116 patients, and calculated the left and right ventricular TD-MPIs. Patients were classified into 3 groups in accordance with their apnea-hypopnea index (AHI) levels: AHImild (≥5 to <15), AHImoderate (≥15 to <30), and AHIsevere (≥30). Left and right ventricular TD-MPI values were higher in the AHIsevere group than in the AHImild and AHImoderate groups (all P <0.05). In addition, right ventricular TD-MPI values in the AHImoderate group were higher than those in the AHImild group (P <0.05). Right ventricular TD-MPI was significantly associated with AHI (β=0.468, P <0.001), left ventricular TD-MPI, and right ventricular early-to-late filling velocities (E/A ratio) in multiple linear regression analysis. On the other hand, left ventricular TD-MPI was significantly associated with right ventricular TD-MPI and left ventricular E/A ratio (both P <0.05). Our results show that OSA severity, determined by means of AHI, is independently associated with impaired right and left ventricular function as indicated by TD-MPI in patients who have OSA and normal ejection fractions.

Aging and the cardiac collagen matrix: Novel mediators of fibrotic remodelling

Cardiovascular disease is a leading cause of death worldwide and there is a pressing need for new therapeutic strategies to treat such conditions. The risk of developing cardiovascular disease increases dramatically with age, yet the majority of experimental research is executed using young animals. The cardiac extracellular matrix (ECM), consisting predominantly of fibrillar collagen, preserves myocardial integrity, provides a means of force transmission and supports myocyte geometry. Disruptions to the finely balanced control of collagen synthesis, post-synthetic deposition, post-translational modification and degradation may have detrimental effects on myocardial functionality. It is now well established that the aged heart is characterized by fibrotic remodelling, but the mechanisms responsible for this are incompletely understood. Furthermore, studies using aged animal models suggest that interstitial remodelling with disease may be age-dependent. Thus with the identification of new therapeutic strategies targeting fibrotic remodelling, it may be necessary to consider age-dependent mechanisms. In this review, we discuss remodelling of the cardiac collagen matrix as a function of age, whilst highlighting potential novel mediators of age-dependent fibrotic pathways.

Cardiac abnormalities assessed by non-invasive techniques in patients with newly diagnosed idiopathic inflammatory myopathies

OBJECTIVES

Knowledge of cardiac involvement in idiopathic inflammatory myopathies (IIM) is limited, especially in the early stage of disease. The objective of the present study was to perform a controlled evaluation of cardiac abnormalities in newly diagnosed, untreated patients with idiopathic inflammatory myopathies (IIM) by means of non-invasive techniques.

METHODS

Fourteen patients with IIM (8 polymyositis, 4 dermatomyositis, 2 cancer-associated dermatomyositis) and 14 gender- and age- matched healthy control subjects were investigated. Participant assessments included a cardiac questionnaire, cardiac troponin-I (TnI), electrocardiogram (standard 12-lead and 48-h Holter monitoring), echocardiography with tissue Doppler measures, cardiac magnetic resonance (CMR) imaging with T2 mapping and semi-quantitative (99m)technetium pyrophosphate ((99m)Tc-PYP) scintigraphy.

RESULTS

Dyspnoea was present in 8 (57%) of the patients compared to none of the controls (p<0.01). Median levels of TnI in patients and controls were 20 ng/L and 6 ng/L, respectively (p=0.06). QTc intervals were prolonged in the patient group (p=0.01). Two patients had systolic dysfunction, and one diastolic dysfunction. The myocardial (99m)Tc-PYP uptake and CMR results differed between patients and controls, albeit not with statistical significance. Overall, cardiac abnormalities were demonstrated in 9 (64%) of the patients versus 2 (14%) of the controls (p=0.02).

CONCLUSIONS

Cardiac abnormalities assessed by TnI, ECG or imaging modalities were significantly more common in newly diagnosed, treatment naïve patients with IIM compared to healthy control subjects. These abnormalities, although subclinical, may indicate that myocardial involvement is common in patients and calls for larger controlled studies and further investigations of the prognostic implications of this finding.

Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery: Diagnoses and Surgical Results in 12 Pediatric Patients

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo-8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.

Alternative right ventricular pacing sites

BACKGROUND

The main adverse effect of chronic stimulation is stimulation-induced heart failure in case of ventricular contraction dyssynchrony. Because of this fact, new techniques of stimulation should be considered to optimize electrotherapy. One of these methods is pacing from alternative right ventricular sites.

OBJECTIVES

The purpose of this article is to review currently accumulated data about alternative sites of cardiac pacing.

MATERIAL AND METHODS

Medline and PubMed bases were used to search English and Polish reports published recently.

RESULTS

Recent studies report a deleterious effect of long term apical pacing. It is suggested that permanent apical stimulation, by omitting physiological conduction pattern with His-Purkinie network, may lead to electrical and mechanical dyssynchrony of heart muscle contraction. In the long term this pathological situation can lead to severe heart failure and death. Because of this, scientists began to search for some alternative sites of cardiac pacing to reduce the deleterious effect of stimulation. Based on current accumulated data, it is suggested that the right ventricular outflow tract, right ventricular septum, direct His-bundle or biventricular pacing are better alternatives due to more physiological electrical impulse propagation within the heart and the reduction of the dyssynchrony effect. These methods should preserve a better left ventricular function and prevent the development of heart failure in permanent paced patients. As there is still not enough, long-term, randomized, prospective, cross-over and multicenter studies, further research is required to validate the benefits of using this kind of therapy.

CONCLUSIONS

The article should pay attention to new sites of cardiac stimulation as a better and safer method of treatment.

Heart rate variability and the metabolic syndrome: a systematic review of the literature

BACKGROUND

A number of cross-sectional studies have examined associations between heart rate variability and metabolic syndrome, but differences in study populations, data collection and analysis methodologies make synthesis difficult. The purpose of this study was to systematically review published primary research examining associations between heart rate variability and metabolic syndrome or its individual risk factors.

METHODS

A systematic literature search of PubMed and EMBASE was conducted to identify relevant articles published from January 1999 to December 2012. Studies were included if they examined associations between heart rate variability analysed by standard protocols and metabolic syndrome risk factors according to published definitions. All papers were scored with a modified Downs and Black instrument, and data were extracted.

RESULTS

Fourteen studies were included. Heart rate variability generally was reduced in women with metabolic syndrome compared to those without, while results in men were inconsistent. Time and frequency domain heart rate variability parameters were associated with individual metabolic syndrome risk factors, though sex differences exist. Only two studies considered nonlinear and Poincaré plot heart rate variability parameters, which were reduced in metabolic syndrome.

CONCLUSIONS

Heart rate variability is altered differently in men and women with metabolic syndrome. Future studies should follow consistent heart rate variability analysis protocols and metabolic syndrome definitions and include more comprehensive analyses to investigate potential mechanisms.

Prevalence and outcome of diastolic dysfunction in liver transplantation recipients

OBJECTIVE

Cirrhotic cardiomyopathy (CCMP) denotes a chronic cardiac dysfunction in cirrhotic patients. It is characterized by systolic (SD) and diastolic dysfunction (DD), and electromechanical abnormalities, in the absence of other cardiac diseases. Liver transplantation (LTx) has a favourable effect on CCMP, but CCMP is in itself a risk factor. Aims of the study were (1) to estimate the prevalence of DD among LTx candidates, (2) to compare outcome between patients with and without DD, and (3) to determine if tricuspid regurgitation (TR) is a predictor of post-transplantation outcome.

METHODS

173 LTx recipients were retrospectively evaluated. Diagnostic criteria for SD and DD were a resting ejection fraction < 55% and an E/A ratio < 1 or a deceleration time > 200 msec on echocardiography, respectively, according to the criteria proposed during the World Congress of Gastroenterology in Montreal, 2005. The difference in outcome between patients with and without DD was evaluated in terms of mortality and cardiovascular complications post-transplantation.

RESULTS

SD and DD were diagnosed in 3 (2%) and 74 (43%) patients, respectively. Patients with DD had significantly older age (P < 0.0001). Regarding outcome, no statistically significant difference could be documented. Moderate/severe TR is, in contrast to no or mild TR, associated with worse posttransplantation outcome (P = 0.01 short-term, P = 0.02 long-term).

CONCLUSION

In this study population, a prevalence of SD and DD of 2% and 43%, respectively, was registered. Outcome does not seem to be strongly affected by the presence of DD. Tricuspid regurgitation severity on echocardiography is predictive of survival.

Cardiac mechanics in patients with human immunodeficiency virus: a study of systolic myocardial deformation in children and young adults

Human immunodeficiency virus (HIV) infection causes dysfunction of different organ systems. Myocardial diastolic dysfunction has been reported previously in an adult HIV population. Our aim was to study myocardial strain in children and young adults infected by HIV who have apparently normal ejection fraction. Forty HIV-infected patients (mean age 20.6 ± 1.5 years) with normal ejection fraction and 55 matched normal controls (mean age 17 ± 1.5 years) were studied by two-dimensional echocardiogram. The images were stored then exported to velocity vector imaging software for analysis. Measures considered were left-ventricular peak global systolic strain (LV S) and strain rate (LV SR) as well as right-ventricular peak global systolic strain (RV S) and strain rate (RV SR). Circumferential measures of the left ventricle included the following: LV circumferential peak global systolic strain (LV circ S), strain rate (LV circ SR), radial velocity (LV rad vel), and rotational velocity (LV rot vel) at the level of the mitral valve. Statistical significance was set at p < 0.05. The means of all longitudinal deformation parameters were significantly lower in HIV patients compared with normal controls: LV S (-14.15 vs. -19.31), LV SR (-0.88 vs. -1.30), RV S (-19.58 vs. -25.09), and RV SR (-1.34 vs. -2.13), respectively (p < 0.05). LV rot vel was lower in patients compared with controls (43.23 vs. 51.71, p = 0.025). LV circ S, LV circ SR, and LV rad vel showed no significant difference between the two groups (p ≥ 0.05). HIV infection affects longitudinal systolic cardiac strain and strain rate in children and young adults. Normal ejection fraction might be attributed to preserved circumferential myocardial deformation. Strain and strain rate may help identify HIV patients at high risk for cardiac dysfunction and allow early detection of silent myocardial depression.

Early myocardial deformation abnormalities in breast cancer survivors

To evaluate the role of 2D myocardial strain (rate) imaging in the detection of early subclinical cardiotoxicity in breast cancer survivors treated with an anthracycline-based chemotherapeutic regimen. 57 adult breast cancer survivors were analyzed 1 year after therapy. All patients underwent biomarker analysis and 2D echocardiography consisting of conventional echocardiographic and strain (rate) parameters. Conventional echocardiographic values were normal. Global longitudinal strain was normal, but 18 % of patients showed a >2 SD decrease when individually compared to reference values. This subgroup showed a decrease in end-systolic and end-diastolic volumes and an increase in left ventricular mass. Radial and circumferential strain rates were significantly decreased in the whole study group. 2D myocardial strain (rate) imaging showed abnormalities in breast cancer survivors, while conventional echocardiographic values remained normal, rendering 2D myocardial strain (rate) imaging an interesting tool for the early detection of anthracycline-induced cardiotoxicity.

Abnormal systolic and diastolic myocardial function in obese asymptomatic adolescents

Structural and functional cardiac changes are known in obese adults. We aimed to assess the relationship between body mass index (BMI) and cardiac function in overweight and obese asymptomatic adolescents. Ninety three healthy adolescents, aged 12.6 ± 1.2 years, received weight, height, BMI, waist, hips, waist/hips ratio assessment, hematology and biochemistry tests and an echocardiogram. Based on BMI, subjects were divided into: lean (L, n=32), overweight (Ov, n=33) and obese (Ob, n=32). Interventricular septal and LV posterior wall thickness were increased parallel to the BMI (L: 0.84 ± 0.1cm, Ov: 0.88 ± 0.1cm, Ob: 0.96 ± 0.1cm, p<0.001, and L: 0.78 ± 0.1cm, Ov: 0.8 ± 0.1cm, Ob: 0.94 ± 0.1cm, p<0.001, respectively) as were relative wall thickness (RWT) and mass index (LVMI) (L: 0.34 ± 0.05, Ov: 0.34 ± 0.05, Ob: 0.40 ± 0.04, p<0.001, and L: 47.7 ± 8.4 g/m(2), Ov: 51.9 ± 8.3g/m(2), Ob: 65.2 ± 13.3g/m(2), p=0<001, respectively). LV early diastolic (E') lateral and septal velocities (L: 15.3 ± 3.9 cm/s, Ov: 13.6 ± 4 cm/s, Ob: 10.5 ± 3.4 cm/s, p<0.001, and L: 12.2 ± 2.3 cm/s, Ov: 11.1 ± 2.4 cm/s, Ob: 9.8 ± 3.1cm/s, p=0.003, respectively), and systolic (S') velocities (L: 9.2 ± 1.4 cm/s, Ov: 9.3 ± 2.3 cm/s, Ob: 8.04 ± 1.5 cm/s, p=0.018, and L: 9.05 ± 2.3 cm/s, Ov: 9 ± 2.4 cm/s, Ob: 7.6 ± 1.1cm/s, p=0.014, respectively) were all reduced, only in obese adolescents. LV lateral E' (r=-0.44, p<0.001) and S' (r=-0.29, p=0.005) correlated with BMI. In asymptomatic adolescents, LV wall is thicker and diastolic function impaired and correlate with BMI. These findings demonstrate early cardiac functional disturbances which might explain the known obesity risk for cardiac disease.

Obesity and insulin resistance induce early development of diastolic dysfunction in young female mice fed a Western diet

Cardiovascular disease (CVD), including heart failure, constitutes the main source of morbidity and mortality in men and women with diabetes. Although healthy young women are protected against CVD, postmenopausal and diabetic women lose this CVD protection. Obesity, insulin resistance, and diabetes promote heart failure in females, and diastolic dysfunction is the earliest manifestation of this heart failure. To examine the mechanisms promoting diastolic dysfunction in insulin-resistant females, this investigation evaluated the impact of 8 weeks of a high-fructose/high-fat Western diet (WD) on insulin sensitivity and cardiac structure and function in young C57BL6/J female versus male mice. Insulin sensitivity was determined by hyperinsulinemic-euglycemic clamps and two-dimensional echocardiograms were used to evaluate cardiac function. Both males and females developed systemic insulin resistance after 8 weeks of a WD. However, only the females developed diastolic dysfunction. The diastolic dysfunction promoted by the WD was accompanied by increases in collagen 1, a marker of stiffness, increased oxidative stress, reduced insulin metabolic signaling, and increased mitochondria and cardiac microvascular alterations as determined by electron microscopy. Aldosterone (a promoter of cardiac stiffness) levels were higher in females compared with males but were not affected by the WD in either gender. These data suggest a predisposition toward developing early diastolic heart failure in females exposed to a WD. These data are consistent with the notion that higher aldosterone levels, in concert with insulin resistance, may promote myocardial stiffness and diastolic dysfunction in response to overnutrition in females.

Impact of diet and exercise training-induced weight loss on myocardial mechanics in severely obese adolescents

OBJECTIVE

Recent findings indicated silent incipient myocardial dysfunction in juvenile obesity despite normal global cardiac function. The present study investigated whether lifestyle intervention is able to favorably impact these obesity-related myocardial abnormalities and whether improvements are related to changes in insulin resistance and cardiac remodeling.

DESIGN AND METHODS

Twenty-eight severe obese adolescents (OB) participated in a 9 month lifestyle intervention program (LIP) based on aerobic exercise and diet. Twenty healthy adolescents (CG) served as controls. Conventional echocardiography and myocardial mechanics were obtained at baseline and follow-up along with insulin resistance.

RESULTS

Insulin sensitivity improved (P < 0.001) and body weight decreased (P < 0.001) consecutive to LIP. At baseline, OB had depressed longitudinal (L) strain (CG: -18.3 ± 2.6, OB: -14.2 ± 3.6%, P < 0.001) and enhanced twist compared to controls. The LIP in OB restored L strain to normal values (-16.9 ± 3.5%, NS), whereas it did not affect twist mechanics. From stepwise multiple regression analysis, only baseline L strain and changes in BMI Z-score (r(2) -adjusted = 0.49, P < 0.001) emerged as independent predictors of L strain changes.

CONCLUSIONS

Juvenile obesity is associated with myocardial mechanic abnormalities that can be partly corrected by lifestyle intervention. Restoration of longitudinal myocardial function occurs in the absence of left ventricular remodeling changes and is not associated with insulin resistance improvements.

Brain sigma-1 receptor stimulation improves mental disorder and cardiac function in mice with myocardial infarction

Mental disorder after myocardial infarction (MI) is reported by many epidemiological studies and is associated with a poor prognosis. The reduction of brain sigma-1 receptor (S1R) plays an important role in the pathogenesis of mental disorder, and we recently demonstrated that the reduction of brain S1R causes sympathoexcitation. However, the role of brain S1R in the association between MI and mental disorder, such as depression or cognitive impairment, remains unclear. To investigate this, we performed left coronary artery ligation on mice to produce an MI model (MI-mice). Compared with sham-operated controls (Sham-mice), MI-mice showed augmented sympathetic activity, decreased cardiac function, and lower S1R expression in both the hypothalamus and hippocampus. Furthermore, MI-mice displayed decreased Y-maze spontaneous alternation (a maker of spatial working memory), decreased circadian variation in locomotor activity, and increased immobility time in the tail suspension test (markers of depression-like behavior). Intracerebroventricular infusion of the S1R agonist PRE084 in MI-mice improved both mental disorder and cardiac function with lowered sympathetic activity and the recovery of the S1R expression in both the hypothalamus and hippocampus. These results indicate that brain S1R is decreased in MI-mice and that this plays an important role in the coexistence of increased heart failure via sympathoexcitation and mental disorders, such as depression or cognitive impairment.

Protective effect of curcumin against cardiac dysfunction in sepsis rats

CONTEXT

The heart is one of the target organs susceptible to attack by sepsis, and protection of the cardiac function in sepsis or alleviation dysfunction caused by sepsis appears a serious and urgent problem.

OBJECTIVE

This study was designed to explore the effect of curcumin on myocardial injury induced by sepsis and to explore the therapeutic effect of curcumin in managing sepsis induced cardiac dysfunction.

METHODS

Cecal ligation and puncture surgery were used to establish the sepsis model. Curcumin was administered by peritoneal injection (200 mg/kg/d, 3 days). The effects of curcumin on the cardiac functions [Ejection Fraction (EF), Fractional Shortening (FS), Cardiac Output (CO), Heart Rate (HR)], body temperature, cTn I and superoxide dismutase levels, malondialdehyde content (an index of lipid peroxidation), and myocardial histopathological and ultrastructural studies were carried out.

RESULTS

We demonstrated that treatment of rats with curcumin significantly decreased elevated levels of cTn I and MDA (p < 0.05) in plasma, and increase the levels of SOD (p < 0.05) after CLP. Moreover, curcumin markedly enhanced the myocardial contractility by increasing the decreased EF and FS in rats with sepsis induced by CLP (p < 0.05). In addition, curcumin could alleviate the myocardial inflammation and structure damage of myocardial cells in sepsis induced by CLP.

CONCLUSION

In conclusion, the results from the present study demonstrate that curcumin has the protective effects on cardiac function in rats with sepsis and curcumin could be considered as an effective and safe therapeutic agent for the management of sepsis induced cardiac dysfunction.

Association between chronic hepatitis C virus infection and high levels of circulating N-terminal pro-brain natriuretic peptide

The association between HCV infection and myocardial disorders remains unclear. This study aimed to assess whether or not HCV infection influences myocardial dysfunction by the use of NT-proBNP, a sensitive marker of myocardial dysfunction. A total of 198 participants [99 patients with chronic HCV infection (aged 46-68 years) and 99 anti-HCV-negative sex and age matched controls] were examined. Serum HCV-RNA level and HCV genotype were tested and liver biopsy was done only for the patient group. The NT-proBNP concentration of the HCV patients (mean 71.6 ± 79.1 pg/ml; median 46.0 pg/ml, range 5.0-400.0) was significantly higher than that of the controls (mean 39.8 ± 24.4 pg/ml; median 35.8 pg/ml, range 7.0-108.0) (P < 0.05). 20.0 % of the HCV patients and 0.6 % of the controls had high NT-proBNP (higher than 125 pg/ml; the single cut off point for patients under 75 years of age) (P < 0.05). Stepwise multiple regression analysis revealed that chronic HCV infection was independently correlated with NT-proBNP level after adjustment for parameters that might influence NT-proBNP (P = 0.005). Our data suggest that chronic HCV infection is associated with increased NT-proBNP, indicating that chronic HCV infection might induce myocardial dysfunction.

Strict glycaemic control improves skin microcirculation in patients with type 2 diabetes: a report from the Diabetes mellitus And Diastolic Dysfunction (DADD) study

BACKGROUND

Microcirculatory and endothelial dysfunction are signs of cardiovascular engagement in patients with type 2 diabetes. This study tested whether glucose normalisation may reverse this.

METHODS

Thirty-nine T2DM patients (age 61±7 years, 58% females) with signs of mild diastolic dysfunction were randomised to strict glucose control based on insulin (I-group; n=21) or oral agents (O-group; n=18) for four months. Skin microcirculation was studied with laser Doppler fluxmetry and endothelial function with brachial artery flow-mediated dilatation.

RESULTS

Glucose control improved (reduction of HbA(1c) I-group = -0.5%; O-group -0.7%; p=0.69). Microcirculation improved in the entire group (n=39) determined by foot laser Doppler fluxmetry (32.2±13.6 vs. 35.3±13.1 perfusion units; p<0.001) and laser Doppler fluxmetry following heating (68.8±34.0 vs. 69.3±25.1 PU; p=0.007). Improvement was more consistent with oral agents than insulin. Endothelial function expressed as flow-mediated dilatation decreased in the I-group (6.0±2.2 to 4.7±3.0%; p=0.037) but remained unchanged in the O-group (4.8±2.3 to 5.0±3.7%; n.s.).

CONCLUSIONS

Glycaemic normalisation improved skin microcirculation but not endothelial function in patients with type 2 diabetes with mild cardiovascular engagement.

[Anesthetic management for laparoscopic sigmoidectomy in a patient with impaired ventricular function caused by cardiac sarcoidosis]

It has been demonstrated that laparoscopic surgery can reduce surgical trauma and postoperative pain, allowing earlier recovery and hospital discharge. However, because patients with severe cardiac depression may not tolerate the adverse respiratory and cardiovascular effects of pneumoperitoneum with a head-up or head-down tilt position, laparoscopic surgery has been avoided in these patients. The present case with low ventricular function (ejection fraction=23-27%) due to cardiac sarcoidosis could successfully undergo laparoscopic sigmoidectomy by using pulmonary artery catheterization. Therefore, laparoscopic surgery can be performed in patients with cardiac dysfunction if the cardiopulmonary responses caused by pneumoperitoneum with a head-up or head-down tilt are sufficiently considered and adverse hemodynamic responses appropriately detected and treated through invasive monitoring techniques such as pulmonary artery catheterization and/or transesophageal echocardiography.

[Ventricular dysfunction and acute pulmonary edema related to intraoperative hypertensive crisis: a case report of clinical and echocardiographic assessment]

A 39-year-old obese woman underwent surgery to open an obstructed tear duct under general anesthesia. After reversal of the neuromuscular block, the patient had a sudden, severe increase in blood pressure related to nonsustained monomorphic ventricular tachycardia. Acute pulmonary edema and cardiogenic shock developed minutes after treatment with propranolol, labetalol, and nitroglycerin. Intraoperative transesophageal echocardiography showed severe diffuse left ventricular hypokinesis with an ejection fraction under 15%. Hemodynamic stability was achieved with inotropic infusions. Angiography ruled out coronary artery injury and echocardiographic follow-up revealed progressive improvement of ventricular function. We analyze diagnostic possibilities and describe the benefits of echocardiography in the diagnosis and treatment of intraoperative acute heart failure.

Stress-induced intraventricular gradients in symptomatic athletes during upright exercise continuous wave Doppler echocardiography

The development of significant intraventricular gradients (IVGs) during exercise has been described anecdotally in athletes. However, the prevalence and clinical effect of this observation are unclear. In addition, the most appropriate exercise technique (upright vs semisupine) for eliciting IVGs also remains unknown. The present study had 2 main aims: (1) to identify the prevalence of exercise IVGs in athletes whose preparticipation cardiovascular screening result for sports practice, according to the European Society of Cardiology guidelines, was positive; and (2) to evaluate the influence of performing exercise echocardiography, as described, on the detection of IVGs. We enrolled 139 consecutive athletes (135 amateurs and 4 professionals, mean age 22 ± 9.9 years; 30 women) who underwent treadmill exercise echocardiography. In each athlete, the IVG was evaluated by continuous wave Doppler during 5 conditions: left lateral decubitus at rest; upright at rest; upright at peak treadmill exercise; upright in the recovery phase; and left lateral decubitus in the recovery phase. All patients had normokinetic regional wall motion at rest and during exercise. According to the detection of IVG during treadmill echocardiography (IVG was considered significant if >30 mm Hg at rest or >50 mm Hg during/after exercise), 2 groups were identified: a group (n = 52), with significant IVG and a group (n = 87) without significant IVG. The IVG was greater in the upright position, both at rest (only 2 athletes from group with IVG) and after exercise (52 athletes, all from group with IVG). The IVG was lower in the recovery phase in the left lateral decubitus position (55 ± 15 mm Hg in 30 athletes, all from group with IVG) than in the upright position in the recovery phase (95 ± 35 mm Hg in 52 athletes, all from group with IVG) and at peak exercise (66 ± 24 mm Hg in 41 athletes from group with IVG). We observed systolic anterior movement of the mitral valve in 33 of the 52 athletes in the group with IVG and in none of the athletes in the group without IVG. In conclusion, in athletes, exercise-induced symptoms and/or ischemia-like electrocardiographic signs are often associated with significant IVG, developing in the absence of wall motion abnormalities. IVG was more evident during post-treadmill upright imaging.