Coronary atherosclerosis in end-stage idiopathic dilated cardiomyopathy: an innocent bystander?

Cardiac magnetic resonance for ventricular arrhythmias: a systematic review and meta-analysis

BACKGROUND

Cardiac magnetic resonance (CMR) allows comprehensive myocardial tissue characterisation, revealing areas of myocardial inflammation or fibrosis that may predispose to ventricular arrhythmias (VAs). With this study, we aimed to estimate the prevalence of structural heart disease (SHD) and decipher the prognostic implications of CMR in selected patients presenting with significant VAs.

METHODS

Electronic databases were searched for studies enrolling adult patients that underwent CMR for diagnostic or prognostic purposes in the setting of significant VAs. A random effects model meta-analysis of proportions was performed to estimate the prevalence of SHD. HRs were pooled together in order to evaluate the prognostic value of CMR.

RESULTS

The prevalence of SHD was reported in 18 studies. In all-comers with significant VAs, the pooled rate of SHD post-CMR evaluation was 39% (24% in the subgroup of premature ventricular contractions and/or non-sustained ventricular tachycardia vs 63% in the subgroup of more complex VAs). A change in diagnosis after use of CMR ranged from 21% to 66% with a pooled average of 35% (29%-41%). A non-ischaemic cardiomyopathy was the most frequently identified SHD (56%), followed by ischaemic heart disease (21%) and hypertrophic cardiomyopathy (5%). After pooling together data from six studies, we found that the presence of late gadolinium enhancement was associated with increased risk of major adverse outcomes in patients with significant VAs (pooled HR: 1.79; 95% CI 1.33 to 2.42).

CONCLUSION

CMR is a valuable tool in the diagnostic and prognostic evaluation of patients with VAs. CMR should be considered early after initial evaluation in the diagnostic algorithm for VAs of unclear aetiology as this strategy may also define prognosis and improve risk stratification.

Empagliflozin Alleviates Carfilzomib-Induced Cardiotoxicity in Mice by Modulating Oxidative Stress, Inflammatory Response, Endoplasmic Reticulum Stress, and Autophagy

Carfilzomib is an irreversible proteasome inhibitor used for multiple myeloma patients. However, carfilzomib treatment is associated with cardiovascular complications. Empagliflozin, an Sodium Glucose Co-transporter 2 inhibitor (SGLT-2) inhibitor, is an oral antidiabetic drug with proven antioxidant and anti-inflammatory properties. The aim of the present study was to determine the cardioprotective effects of empagliflozin against carfilzomib-induced cardiotoxicity. C57BL/6 mice were randomly divided into four groups: control, empagliflozin, carfilzomib, and carfilzomib + empagliflozin. Empagliflozin prevented carfilzomib-induced cardiotoxicity by ameliorating histological alterations, CK-MB, and troponin-I. Moreover, it inhibited carfilzomib-induced oxidative damage and inflammation via its action on catalase activity, reduced glutathione levels and superoxide dismutase activity, and reduced nuclear factor-κB (p65) and cytokine levels. Mechanistically, empagliflozin abrogated endoplasmic reticulum stress induced by carfilzomib, as evidenced by the effect on the Glucose Regulated Protein-78 (GRP-78)/Activating Transcription Factor 6 (ATF6)/C/EBP homologous protein (CHOP) axis. Intriguingly, carfilzomib significantly induced autophagy, an effect that was further enhanced by empagliflozin, evidenced by increased LC3B and beclin-1 mRNA expression and reduced p62 expression. The effect of empagliflozin on apoptosis was confirmed by reduced expression of active caspase-3. Importantly, empagliflozin did not alter the cytotoxic effect of carfilzomib on human U266B1 multiple myeloma cells. our findings suggest that empagliflozin may provide a new therapeutic strategy to mitigate carfilzomib-induced cardiotoxicity in multiple myeloma patients.

Characteristics of the phenotype of mixed cardiomyopathy in patients with implantable cardioverter-defibrillators

BACKGROUND OR PURPOSE

The prognosis of m ixed cardiomyopathy (CMP) in patients with implanted cardioverter-defibrillators (ICDs) has not been investigated. We aim to study the demographic, clinical, device therapies and survival characteristics of mixed CMP in a cohort of patients implanted with a defibrillator.

METHODS

The term mixed CMP was used to categorise patients with impaired left ventricular ejection fraction attributed to documented non-ischemic triggers with concomitant moderate coronary artery disease. This is a single center observational cohort of 526 patients with a mean follow-up of 8.7 ± 3.5 years.

RESULTS

There were 42.5% patients with ischemic cardiomyopathy (ICM), 26.9% with non-ischemic cardiomyopathy (NICM) and 30.6% with mixed CMP. Mixed CMP, compared to NICM, was associated with higher mean age (69.1 ± 9.6 years), atrial fibrillation (55.3%) and greater incidence of comorbidities. The proportion of patients with mixed CMP receiving device shocks was 23.6%, compared to 18.4% in NICM and 27% in ICM. The VT cycle length recorded in mixed CMP (281.6 ± 43.1 ms) was comparable with ICM (282.5 ± 44 ms; p = 0.9) and lesser than NICM (297.7 ± 48.7 ms; p = 0.1). All-cause mortality in mixed CMP (21.1%) was similar to ICM (20.1%; p = 0.8) and higher than NICM (15.6%; p = 0.2). The Kaplan-Meier curves revealed hazards of 1.57 (95% CI: 0.91, 2.68) for mixed CMP compared to NICM.

CONCLUSION

In a cohort of patients with ICD, the group with mixed CMP represents a phenotype predominantly comprised of the elderly with a higher incidence of comorbidities. Mixed CMP resembles ICM in terms of number of device shocks and VT cycle length. Trends of long-term prognosis of patients with mixed CMP are worse than NICM and similar to ICM.

Association between low-density lipoprotein cholesterol level and all-cause mortality in idiopathic dilated cardiomyopathy patients: a single-institutional study

AIMS

To determine the association between all-cause mortality and low-density lipoprotein cholesterol (LDL-C) in patients with idiopathic cardiomyopathy (iDCM).

BACKGROUND

LDL-C had long been considered as a dangerous predictor of cardiovascular diseases; however, the correlation between them was not fully clarified.

METHODS

A total of 1058 patients who met the World Health Organization criteria for iDCM in West China Hospital (2009-2016) were enrolled in this retrospective study. Baseline demographic characteristics and correlations between variables were calculated and analyzed, and potential predictors were explored using univariate and multivariate regressions. Cox proportional hazards models were used to determine correlation on a continuous scale.

RESULTS

LDL-C is an independent prognostic factor and higher LDL-C levels are associated with better prognosis in iDCM patients according to cox regression analysis. Compared with individuals which LDL > 2.28 mmol/L (75th-100th percentile), the multivariable-adjusted hazard ratio for all-cause mortality was 1.52 (95%CI: 1.03-2.26) in patients with LDL-C < 1.78 mmol/L (0-25th percentile). In patients with New York Heart Association function III and IV, LDL-C levels have a hazard ratio of 0.83 (confidence interval 0.73-0.95).

CONCLUSIONS

In patients with iDCM, lower LDL-C level was associated with an increased risk of all-cause mortality. The correlation between mortality and LDL-C level was stronger in patients with worse heart function. LDL-C levels have a potential predictive value in iDCM patients.

Coronary Artery Spasm-Related Heart Failure Syndrome: Literature Review

Although heart failure (HF) is a clinical syndrome that becomes worse over time, certain cases can be reversed with appropriate treatments. While coronary artery spasm (CAS) is still underappreciated and may be misdiagnosed, ischemia due to coronary artery disease and CAS is becoming the single most frequent cause of HF worldwide. CAS could lead to syncope, HF, arrhythmias, and myocardial ischemic syndromes such as asymptomatic ischemia, rest and/or effort angina, myocardial infarction, and sudden death. Albeit the clinical significance of asymptomatic CAS has been undervalued, affected individuals compared with those with classic Heberden's angina pectoris are at higher risk of syncope, life-threatening arrhythmias, and sudden death. As a result, a prompt diagnosis implements appropriate treatment strategies, which have significant life-changing consequences to prevent CAS-related complications, such as HF. Although an accurate diagnosis depends mainly on coronary angiography and provocative testing, clinical characteristics may help decision-making. Because the majority of CAS-related HF (CASHF) patients present with less severe phenotypes than overt HF, it underscores the importance of understanding risk factors correlated with CAS to prevent the future burden of HF. This narrative literature review summarises and discusses separately the epidemiology, clinical features, pathophysiology, and management of patients with CASHF.

Genetics and clinics: together to diagnose cardiomyopathies

The diagnostic paths of hereditary cardiomyopathies (CMPs) include both clinical and molecular genetics. The first step is the clinical diagnosis that guides the decisions about treatments, monitoring, prognostic stratification, and prevention of major events. The type of CMP [hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy (ARVC)] is defined by the phenotype, and the genetic testing may identify the precise cause. Furthermore, genetic testing provides a pre-clinical diagnosis in unaffected family members and the basis for prenatal diagnosis. It can contribute to risk stratification (e.g. LMNA) and can be a major diagnostic criterion (e.g. ARVC). The test can be limited to a single gene when the pre-test diagnostic hypothesis is based on proven clinical evidence (e.g. GLA for Fabry disease). Alternatively, it can be expanded from a multigene panel to a whole exome or whole genome sequencing when the pre-test hypothesis is a genetically heterogeneous disease. In the last decade, the study of larger genomic targets led to the identification of numerous gene variants not only pathogenic (clinically actionable) but also of uncertain clinical significance (not actionable). For the latter, the pillar of the genetic diagnosis is the correct interpretation of the pathogenicity of genetic variants, which is evaluated using both bioinformatics and clinical-genetic criteria about the patient and family. In this context, cardiologists play a central role in the interpretation of genetic tests, performing the deep-phenotyping of variant carriers and establishing the co-segregation of the genotype with the phenotype in families.

Prognosis of Coronary Atherosclerotic Burden in Non-Ischemic Dilated Cardiomyopathies

Background: Atherosclerosis is associated with a worse prognosis in many diseases such as ischemic cardiomyopathy, but its impact in non-ischemic dilated cardiomyopathy (dCMP) is lesser known. Our aim was to study the prognostic impact of coronary atherosclerotic burden (CAB) in patients with dCMP. Methods: Consecutive patients with dCMP and left ventricular (LV) dysfunction diagnosed by concomitant analysis of invasive coronary angiography (ICA) and CMR imaging were identified from registry-database. CAB was measured by Gensini score. The primary composite endpoint was the occurrence of major adverse cardiovascular events (MACE) defined as cardiovascular (CV) mortality, non-fatal MI and unplanned myocardial revascularization. The results of 139 patients constituting the prospective study population (mean age 59.4 ± 14.7 years old, 74% male), average LV ejection fraction was 31.1 ± 11.02%, median Gensini score was 0 (0–3), and mid-wall late gadolinium enhancement (LGE) was the most frequent LGE pattern (42%). Over a median follow-up of 2.8 years, 9% of patients presented MACE. Patients with MACE had significantly higher CAB compared to those who were free of events (0 (0–3) vs. 3.75 (2–15), p < 0.0001). CAB remained the significant predictor of MACE on multivariate logistic analysis (OR: 1.12, CI: 1.01–1.23, p = 0.02). Conclusion: High CAB may be a new prognostic factor in dCMP patients.

Differentiating Nonischemic Dilated Cardiomyopathy With Incidental Infarction From Ischemic Cardiomyopathy by Geometric Indices Derived From Cardiovascular Magnetic Resonance

PURPOSE

The purpose of this study was to differentiate nonischemic dilated cardiomyopathy with incidental myocardial infarction (NICM with incidental MI) from ischemic cardiomyopathy (ICM) by integrating left ventricular (LV) geometric indices and ischemic late gadolinium enhancement (LGE), obtained from cardiac magnetic resonance (CMR) imaging.

MATERIALS AND METHODS

All subjects were studied on a 1.5 Tesla magnetic resonance imaging scanner. All patients had an LV ejection fraction (LVEF) <50% with LV dilation. LV end-diastolic volume (LVEDV), LVEDV index (LVEDVi), LVEF, the number and distribution of ischemic LGE segments, and ratios of volumetric and functional indices to ischemic LGE segments were determined. Logistic regression was used to detect the independent predictor of ICM. Receiver operating characteristic analysis differentiated NICM with incidental MI from ICM.

RESULTS

Of a total of 63 patients enrolled, 45 patients had ICM, and 18 patients had NICM with incidental MI. Both groups had similar LVEF. Compared with ICM, NICM with incidental MI had more LV dilation, whereas ICM had more ischemic LGE segments. A higher number of ischamic LGE segments remained an independent predictor of ICM (odds ratio: 18.2, 95% confidence interval: 1.64-201.34, P=0.018). The optimal cut-off value for detecting NICM with incidental MI is the ratio of LVEDVi to the number of ischemic LGE segments over 25 mL/m2/segment (sensitivity 100%, specificity 91%, P<0.0001).

CONCLUSION

Patients with NICM with incidental MI can be reliably distinguished from ICM using the ratio of LVEDVi divided by the number of ischemic LGE segments. This technique may improve diagnosis and help aid management of patients with cardiomyopathy and coexistent coronary artery disease.

Rutin Attenuates Carfilzomib-Induced Cardiotoxicity Through Inhibition of NF-κB, Hypertrophic Gene Expression and Oxidative Stress

Carfilzomib is a proteasome inhibitor, commonly used in multiple myeloma, but its clinical use may be limited due to cardiotoxicity. This study was aimed to evaluate the influence of rutin in carfilzomib-induced cardiotoxicity in rats. Wistar albino male rats weighing 200-250 g (approximately 10 weeks old) were taken for this study. Animals were divided into four groups of six animals each. Group 1 served as normal control (NC), received normal saline; group 2 animals received carfilzomib (dissolved in 1 % DMSO) alone; group 3 animals received rutin (20 mg/kg) + carfilzomib; and group 4 animals received rutin (40 mg/kg) + carfilzomib. Hematological changes, biochemical changes, oxidative stress, hypertrophic gene expression, apoptotic gene expression, NFκB and IκB-α protein expression and histopathological evaluation were done to confirm the finding of carfilzomib-induced cardiotoxicity. Treatment with rutin decreased the carfilzomib-induced changes in cardiac enzymes such as lactate dehydrogenase, creatine kinase (CK) and CK-MB. For the assessment of cardiotoxicity, we further evaluated cardiac hypertrophic gene and apoptotic gene expression such as α-MHC, β-MHC and BNP and NF-κB and p53 gene expression, respectively, using RT-PCR. Western blot analysis showed that rutin treatment prevented the activation of NF-κB by increasing the expression of IκB-α. Rutin also attenuated the effects of carfilzomib on oxidant-antioxidant including malondialdehyde and reduced glutathione. Histopathological study clearly confirmed that rutin attenuated carfilzomib-induced cardiotoxicity in rats.

Apremilast reversed carfilzomib-induced cardiotoxicity through inhibition of oxidative stress, NF-κB and MAPK signaling in rats

Carfilzomib (CFZ), is a potent, selective second generation proteasome inhibitor, used for the treatment of multiple myeloma. The aim of the present study was to investigate the possible protective effect of apremilast (AP) on the CFZ -induced cardiotoxicity. Rats were randomly divided into four groups: Group 1, served as the control group, received normal saline. Group 2, served as the toxic group, received CFZ (4 mg/kg, intraperitoneally [i.p.]). Groups 3 and 4, served as treatment groups, and received CFZ with concomitant oral administration of AP in doses of 10 and 20 mg/kg/day, respectively. In the present study, administration of CFZ resulted in a significant increase in serum aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase-MB (CK-MB), which were reversed by treatment with AP. CFZ resulted in a significant increase in heart malondialdehyde (MDA) contents and decrease in cardiac glutathione (GSH) level and catalase (CAT) enzyme activity which were significantly reversed by treatment with AP. Induction of cardiotoxicity by CFZ significantly increased caspase-3 enzyme activity which were reversed by treatment with AP. RT-PCR analysis revealed an increased mRNA expression of NF-κB, ERK and JNK which were reversed by treatment with AP in cardiac tissues. Western blot analysis revealed an increased expression of caspase-3 and NF-κB p65 and a decrease expression of inhibitory kappa B-alpha (Iκbα) with CFZ, which were reversed by treatment with AP. In conclusion, apremilast showed protective effect against CFZ-induced cardiotoxicity.

Carfilzomib-induced cardiotoxicity mitigated by dexrazoxane through inhibition of hypertrophic gene expression and oxidative stress in rats

Carfilzomib (CFZ) is an inhibitor of proteasome that is generally used in the treatment of multiple myeloma but due to its cardiotoxicity clinical use may be limited. Dexrazoxane (DZR), an inhibitor of topoisomerase-II, prevents cardiac damage by reducing the formation of reactive oxygen species and hypertrophic gene expression. This study evaluated the protective effect of DZR on CFZ-induced cardiotoxicity. Thirty-two male Albino rats were randomly divided into four groups (n = 8). Group I received DMSO, Group II received CFZ (4 mg/kg, intraperitoneally [i.p.]) twice weekly up to day 16, Group III received DZR (20 mg/kg, i.p.) for 16 days and CFZ twice weekly for 16, Group IV received DZR (40 mg/kg, i.p.) for 16 days and CFZ twice weekly for 16. CFZ-induced cardiotoxicity was assessed by hematological, biochemical, mRNA expression, oxidative stress and histopathological studies. CFZ-induced significant changes have been observed in blood parameters including red blood cells, white blood cells, hemoglobin and hematocrit concentrations which were associated with increase in cardiac enzymes markers like creatine kinase (CK), CK-MB and lactate dehydrogenase. Treatment with DZR reversed the hematological statistics and the biochemical markers of CFZ-induced cardiotoxicity. Furthermore, DZR also attenuated the effects of CFZ-induced toxic effect on redox markers such as malondialdehyde and reduced glutathione. Above findings were further confirmed by beta-myosin heavy chain (β-MHC) and alpha-MHC (α-MHC) gene expression. Histopathological reports suggested that DZR ameliorates CFZ-induced changes in cardiac cellular architecture in rats. These results confirm that DZR protects heart from CFZ-induced cardiotoxicity.

Clinical characteristics, morbidity, and prognostic value of concomitant coronary artery disease in idiopathic dilated cardiomyopathy

BACKGROUND

Patients with idiopathic dilated cardiomyopathy (dCMP) might present coronary artery disease (CAD) concomitant to dCMP and prognostic differences between ischemic heart disease and non-ischemic cardiomyopathy have been described. Clinical characteristics and prognostic implications of concomitant CAD in patients with dCMP are largely unknown.

METHODS

A total of 1,263 patients with chronic systolic dysfunction from dCMP-of these 67.1 % (n = 847; 72.3 % men) without and 32.9 % (n = 416; 80.8 % men) with concomitant CAD were included and baseline clinical characteristics noted. They were followed prospectively for 36.3 (20.8-65.0) months, representing 5,168 patient-years. All-cause mortality was the primary endpoint; and decompensation requiring hospitalisation as well as the combined endpoint thereof were secondary endpoints.

RESULTS

Independent significant predictors of CAD were smoking status (current smoker: OR 2.68, 95 % CI 1.61-4.46; p < 0.001; past smoker: OR 2.52, 95 % CI 1.40-4.52; p < 0.005; each vs. non-smoker), presence of dyslipidemia (OR 3.46, 95 % CI 2.23-5.35; p < 0.001), age (OR 1.06, 95 % CI 1.04-1.08; p < 0.001), and female sex (OR 0.49, 95 % CI 0.29-0.81; p = 0.005). The presence of CAD was not a significant predictor of all-cause mortality (adjusted HR 0.74, 95 % CI 0.36-1.54; p = 0.42), morbidity (adjusted HR 1.48, 95 % CI 0.55-3.99; p = 0.44), or the combined endpoint (HR 0.65, 95 % CI 0.24-1.78; p = 0.40).

CONCLUSION

Concomitant CAD is common in patients with dCMP. Clinical predictors of its presence are largely coincident with classic risk factors in the general population. The presence of concomitant CAD appears not to be associated with adverse prognosis (morbidity or mortality) in patients with dCMP.

The causes, consequences, and treatment of left or right heart failure

Chronic heart failure (HF) is a cardiovascular disease of cardinal importance because of several factors: a) an increasing occurrence due to the aging of the population, primary and secondary prevention of cardiovascular events, and modern advances in therapy, b) a bad prognosis: around 65% of patients are dead within 5 years of diagnosis, c) a high economic cost: HF accounts for 1% to 2% of total health care expenditure. This review focuses on the main causes, consequences in terms of morbidity, mortality and costs and treatment of HF.

Association of cardiomegaly with coronary artery histopathology and its relationship to atheroma

AIMS

Hypertrophied hearts at autopsy often display excessive coronary artery atherosclerosis, but the histopathology of coronary arteries in hearts with and without cardiomegaly has rarely been compared.

METHODS

In this study, forensic autopsies provided hearts with unexplained enlargement plus comparison specimens. Right coronary artery was opened longitudinally and flattened for formalin fixation and H&E-stained paraffin sections were cut perpendicular to the endothelial surface. The micro-scopically observed presence or absence of a necrotic atheroma in the specimen was recorded. At multiple sites far removed from any form of atherosclerosis, measurements were taken of intimal thickness, numbers of smooth muscle cells (SMC) and their ratio, the thickness per SMC, averaged over the entire nonatheromatous arterial length. When the mean thickness per SMC exceeded a certain cutoff point, the artery was declared likely to contain a necrotic atheroma.

RESULTS

The prevalence of specimens with necrotic atheromas increased stepwise with increasing heart weight, equally with fatal or with incidental cardiomegaly, and equally with hypertension- or obesity-related hypertrophy, rejecting further inclusion of appreciable age, race, or gender effects. The prevalence of specimens with thickness per SMC exceeding the cutoff point was almost always nearly identical to the prevalence of observed necrotic atheroma, showing the two variables to be tightly linked to each other with quantitative consistency across group comparisons of every form.

CONCLUSIONS

In summary, cardiomegaly, irrespective of the specific cause, seems to accelerate the risk of atheromas, and to do so by first altering the arterial architecture, especially by increasing intimal thickness per SMC.

Heart failure in the twenty-first century: is it a coronary artery disease or hypertension problem?

Hypertension and coronary disease are major risk factors for the incidence and progression of heart failure. These two risk factors frequently coexist, and have additive and synergistic effects that promote both left ventricular remodeling and heart failure in the general population. The relative contributions of these two risk factors to heart failure burden in the community may vary based on age, gender, and race. In general, attribution of heart failure in the community to solely one of these two risk factors is inappropriate. Prevention of both hypertension and coronary disease is important for preventing heart failure in the twenty-first century.

Nicotine effect on cardiovascular system and ion channels

Smoking is a leading cause of cardiovascular disease, hypertension, myocardial infarction, and stroke. Nicotine is one of the components of cigarette smoke. Nicotine effects on the cardiovascular system reflect the activity of the nicotine receptors centrally and on peripheral autonomic ganglia. It has been found that cigarette smoke extract-induced contraction of porcine coronary arteries is related to superoxide anion-mediated degradation of nitric oxide. Treatment of rabbit aortas with an oxygen free radicals scavenger attenuated cigarette smoke impairment of arterial relaxation. Treatment of smokers with vitamin C, an antioxidant, improved impaired endothelium-dependent reactivity of large peripheral arteries. Thus it appears that chronic smoking and acute exposure to cigarette smoke extract may alter endothelium-dependent reactivity via the production of oxygen derived free radicals. This review discusses the effects of nicotine on resistance arterioles, compliance arteries, smooth muscle cells, and ion channels in the cardiovascular system. We discuss studies performed on humans, nicotine-exposed animals, and cell cultures yielding varying and inconsistent results that may be due to differences in experimental design, species, and the dose of exposure. Nicotine exposure appears to induce a combination of free radical production, vascular wall adhesion, and a reduction of fibrinolytic activity in the plasma.