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Background Renovascular hypertension ( RVH ) impairs cardiac structure and left ventricular ( LV ) function, but whether mitochondrial injury is implicated in RVH ‐induced myocardial damage and dysfunction has not been defined. We hypothesized that cardiac remodeling in swine RVH is partly attributable to cardiac mitochondrial injury. Methods and Results After 12 weeks of hypercholesterolemic ( HC )‐ RVH or control (n=14 each), pigs were treated for another 4 weeks with vehicle or with the mitochondrial‐targeted peptide ( MTP ), Bendavia (0.1 mg/kg subcutaneously, 5 days/week), which stabilizes mitochondrial inner‐membrane cardiolipin (n=7 each). Cardiac function was subsequently assessed by multidetector‐computed tomography and oxygenation by blood‐oxygen‐level–dependent magnetic resonance imaging. Cardiolipin content, mitochondrial biogenesis, as well as sarcoplasmic‐reticulum calcium cycling, myocardial tissue injury, and coronary endothelial function were assessed ex vivo. Additionally, mitochondrial cardiolipin content, oxidative stress, and bioenergetics were assessed in rat cardiomyocytes incubated with tert‐butyl hydroperoxide ( tBHP ) untreated or treated with MTP . Chronic mitoprotection in vivo restored cardiolipin content and mitochondrial biogenesis. Thapsigargin‐sensitive sarcoplasmic reticulum Ca 2+ ‐ ATP ase activity that declined in HC ‐ RVH normalized in MTP ‐treated pigs. Mitoprotection also improved LV relaxation (E/A ratio) and ameliorated cardiac hypertrophy, without affecting blood pressure or systolic function. Myocardial remodeling and coronary endothelial function improved only in MTP ‐treated pigs. In tBHP ‐treated cardiomyocytes, mitochondrial targeting attenuated a fall in cardiolipin content and bioenergetics. Conclusions Chronic mitoprotection blunted myocardial hypertrophy, improved LV relaxation, and attenuated myocardial cellular and microvascular remodeling, despite sustained HC ‐ RVH , suggesting that mitochondrial injury partly contributes to hypertensive cardiomyopathy.

Abstract Obesity is a major risk factor for a number of chronic diseases, including diabetes, cardiovascular diseases, and cancer. Expansion of the adipose mass requires adipocyte precursor cells that originate from multipotent adipose-derived stromal cells (ASCs), which in turn also participate in repair activities. ASC function might decline in a disease milieu, but it remains unclear whether ASC function varies during the development of obesity. We tested the hypothesis that microenvironmental inflammatory changes during development of metabolic disorders in obesity affect ASC function. Domestic pigs were fed with an atherogenic (n = 7) or normal (n = 7) diet for 16 weeks. Abdominal adipose tissue biopsies were collected after 8, 12, and 16 weeks of diet for ASC isolation and immunohistochemistry of in situ ASCs and tumor necrosis factor-α (TNF-α). Longitudinal changes in proliferation, differentiation, and anti-inflammatory functions of ASCs were assessed. At 16 weeks, upregulated TNF-α expression in adipose tissue from obese pigs was accompanied by increased numbers of adipocyte progenitors (CD24+/CD34+) in adipose tissue and enlarged adipocyte size. In vitro, ASCs from obese pigs showed enhanced adipogenic and osteogenic propensity, which was abolished by anti-TNF-α treatment, whereas lean ASCs treated with TNF-α showed enhanced adipogenesis. Furthermore, obese ASCs showed increased senescence compared with lean ASCs, whereas their immunomodulatory capacity was preserved. Adipose tissue inflammation promotes an increase in resident adipocyte progenitors and upregulated TNF-α enhances ASC adipogenesis. Thus, adipose tissue anti-inflammatory strategies might be a novel target to attenuate obesity and its complications. Significance Adipose-derived stromal cell (ASC) function might decline in a disease milieu, but it remains unclear whether ASC function varies during the development of obesity. This study tested the hypothesis that microenvironmental inflammatory changes during development of metabolic disorders in obesity affect ASC function. It was found that ASCs show increased propensity for differentiation into adipocytes, which is partly mediated by upregulated tumor necrosis factor-α (TNF-α), likely in their adipose tissue microenvironment. Furthermore, TNF-α magnified obese ASC senescence, although it did not regulate their anti-inflammatory properties. Thus, adipose tissue inflammation might be a novel therapeutic target to avert ASC maldifferentiation and senescence.

Rationale: Coronary endothelial dysfunction (ED)—an early marker of atherosclerosis—increases the risk of cardiovascular events. Objective: We tested the hypothesis that cholesterol efflux capacity and high-density lipoprotein (HDL) particle concentration predict coronary ED better than HDL-cholesterol (HDL-C). Methods and Results: We studied 80 subjects with nonobstructive (<30% stenosis) coronary artery disease. ED was defined as <50% change in coronary blood flow in response to intracoronary infusions of acetylcholine during diagnostic coronary angiography. Cholesterol efflux capacity and HDL particle concentration (HDL-P IMA ) were assessed with validated assays. Cholesterol efflux capacity and HDL-P IMA were both strong, inverse predictors of ED ( P <0.001 and 0.005, respectively). In contrast, HDL-C and other traditional lipid risk factors did not differ significantly between control and ED subjects. Large HDL particles were markedly decreased in ED subjects (33%; P =0.005). After correction for HDL-C, both efflux capacity and HDL-P IMA remained significant predictors of ED status. HDL-P IMA explained cholesterol efflux capacity more effectively than HDL-C ( r =0.54 and 0.36, respectively). The efflux capacities of isolated HDL and serum HDL correlated strongly ( r =0.49). Conclusions: Cholesterol efflux capacity and HDL-P IMA are reduced in subjects with coronary ED, independently of HDL-C. Alterations in HDL-P IMA and HDL itself account for a much larger fraction of the variation in cholesterol efflux capacity than does HDL-C. A selective decrease in large HDL particles may contribute to impaired cholesterol efflux capacity in ED subjects. These observations support a role for HDL size, concentration, and function as markers—and perhaps mediators—of coronary atherosclerosis in humans.

Background Endothelial dysfunction is an early stage of atherosclerosis. Single‐nucleotide polymorphisms ( SNP s) have been associated with vascular dysfunction, cardiac events, and coronary artery remodeling. We aimed to detect SNP s associated with endothelial dysfunction and determine whether these associations are sex specific. Methods and Results Six hundred forty‐three subjects without significant obstructive coronary artery disease underwent invasive coronary endothelial function assessment. We collected data from 1536 SNP s that had previously been associated with vasoreactivity, angiogenesis, inflammation, artery calcification, atherosclerotic risk factors, insulin resistance, hormone levels, blood coagulability, or with coronary heart disease. Coronary vascular reactivity was assessed by the percent change in coronary artery diameter ≤ −20% after an intracoronary bolus injection of acetylcholine on invasive coronary physiology study. SNP s significantly associated with coronary epicardial endothelial dysfunction were ADORA 1 , KCNQ 1 , and DNAJC 4 in the whole cohort, LPA , MYBPH , ADORA 3 , and PON 1 in women and KIF 6 and NFKB 1 in men ( P <0.01). Conclusions We have identified several significant SNP s that are associated with an increased risk of coronary endothelial dysfunction. These associations appear to be sex specific and may explain gender‐related differences in development of atherosclerosis.

Introduction Apical ballooning syndrome (ABS) is typically associated with an antecedent stressful situation. Affected patients have been reported to have higher frequencies of premorbid affective disorders. We hypothesised that patients with ABS would have elevated levels of neuroticism (tendency to experience negative affect) and greater vulnerability to stress. Methods In this cross-sectional study, all active participants in the Mayo Clinic ABS prospective follow-up registry were invited to complete the third edition of the NEO Personality Inventory (NEO-PI-3). The NEO-PI-3 is the universally accepted measure of the ‘Five-Factor Model’ of personality. Inventory responses were scored using the NEO-PI-3 computer program and the data were compared with US normative sample used in standardisation of the inventory. Significance was set at 0.0014 to account for multiple comparisons. Results Of 106 registry participants approached, 53 completed the inventory. There was no difference in age, gender, time from ABS diagnosis, type of antecedent stressor (emotional, physical or none) or severity of initial illness between the responders and non-responders. Responders had mean Neuroticism T-scores of 48.0±10.6 (95% CI 45.1 to 50.9); p=0.18, when compared with the normal mean of 50. There was also no significant difference in the facet scale of Vulnerability: 46.9±8.4 (44.6 to 49.2), p=0.038, at α=0.0014. Conclusions Contrary to our hypothesis, patients with ABS do not manifest higher levels of neuroticism and do not have greater vulnerability to stress than the general population. These findings have implications for the clinicians’ perception of, and approach to, patients with ABS.

Abstract BACKGROUND Revascularization of a stenotic renal artery improves kidney function only in select patients with renovascular hypertension (HT) secondary to atherosclerosis. However, the effects of reversal of renovascular HT (RRHT) on the nonstenotic kidney are unclear. We hypothesized that concurrent hypercholesterolemia (HC) attenuates nonstenotic kidney recovery. METHODS Female domestic pigs were randomized as Normal, renovascular HT, HT+RRHT, HTC (renovascular HT and HC), and HTC+RHT ( n = 7 each). RRHT or sham was performed after 6 weeks of HT. Nonstenotic renal blood flow, glomerular filtration rate, and injurious pathways were studied 4 weeks later. RESULTS Mean arterial pressure increased similarly in HT and HTC and decreased after RRHT. Oxidative stress increased in HT and HTC kidneys, and decreased in HT+RRHT, but remained elevated in HTC+RRHT. Renal interstitial fibrosis, glomerulosclerosis, and tubular injury were all attenuated in HT+RRHT, but not HTC+RRHT. Endothelin-1 signaling and PGF2α isoprostane levels were elevated in both HTC and HTC+RRHT pigs. CONCLUSIONS RRHT reverses nonstenotic kidney injury in experimental renovascular HT, but concurrent HC blunts regression of kidney injury, possibly due to predominant vasoconstrictors and oxidative stress. These findings reinforce the contribution of the nonstenotic kidney and of prevailing cardiovascular risk factors to irreversibility of kidney dysfunction after revascularization.

ABSTRACTBackgroundThe objective of this study was to investigate cardiovascular disease risk factor (cvRF) profiles and compare their trends over 17 years in patients with and without acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI).HypothesisTime trends of cvRF are different between ACS and non‐ACS patients.MethodsThis study was a time‐trend analysis from 1994 to 2010 within the Mayo Clinic PCI registry. Outcome measures were incidence and prevalence of cvRF, including the Framingham Risk Score (FRS), at the time of admission for PCI.ResultsAge of non‐ACS patients was higher than that of ACS patients, and age distribution slightly shifted toward older age in both groups (P for trend <0.001). There was no difference in FRS between the 2 groups; however, 10‐year cardiovascular disease risk (%) remained higher in non‐ACS than in ACS patients, decreasing over time. Diastolic blood pressure and high‐density lipoprotein cholesterol were higher in non‐ACS patients, but total cholesterol and low‐density lipoprotein cholesterol were higher in ACS patients, with an improving trend over time. Prevalence of diabetes mellitus, hypertension, and history of hypercholesterolemia were higher in non‐ACS patients, increasing over time. Smoking did not change over time. Use of most medications increased over time in both groups.ConclusionsMost cvRFs and their time trends exhibited statistically significant differences between ACS and non‐ACS patients, except systolic blood pressure, body mass index, and history of myocardial infarction. A new risk‐factor profile assessment may be needed for stratification of PCI patients according to ACS and non‐ACS status. Clinical and public‐health interventions should consider different approaches to ACS and non‐ACS patients.

ObjectivesTo determine the feasibility of automated co‐registration of angiography and intravascular ultrasound (IVUS) to facilitate integration of these two imaging modalities in a synchronous manner.BackgroundIVUS provides cross‐sectional imaging of coronary arteries but lacks overview of the vascular territory provided by angiography. Co‐registration of angiography and IVUS would increase utility of IVUS in the clinical setting.MethodsForty‐nine consecutive patients undergoing surveillance for cardiac allograft vasculopathy with angiography and IVUS of the left anterior descending artery (LAD) were enrolled. A pre‐IVUS angiogram of the LAD was performed followed by an ECG‐triggered fluoroscopy (ECGTF) during IVUS pullback at 0.5 mm/s using an automatic pullback device. ECGTF was used to track the IVUS catheter during pullback and establish a spatial relationship to the pre‐IVUS angiogram. Angio‐IVUS co‐registration was performed with a research prototype (Siemens Healthcare, Germany) and accuracy was evaluated by distance mismatch between angiography and IVUS images at vessel bifurcations.ResultsMedian age was 54 (44.5, 67) years. The population was 82.6% male with minimal risk factors. The median (IQR) co‐registration distance mismatch measured at 108 bifurcations in 42 (85%) patients was 0.35 (0.00–1.16) mm. Seven patients were excluded due to inappropriate data acquisition (n = 3) and failure of tracking (n = 4), e.g., due to overlapping sternal wires. Estimated effective radiation dose for ECGTF was 0.09 mSv.ConclusionThis study demonstrates the feasibility of angio‐IVUS co‐registration which may be used as a clinical tool for localizing IVUS cross‐sections along an angiographic roadmap. © 2015 Wiley Periodicals, Inc.

Background Endothelial dysfunction plays a pivotal role in cardiovascular disease progression, and is associated with adverse events. The purpose of this systematic review and meta‐analysis was to investigate the prognostic magnitude of noninvasive peripheral endothelial function tests, brachial artery flow‐mediated dilation (FMD), and reactive hyperemia–‐peripheral arterial tonometry (RH‐PAT) for future cardiovascular events. Methods and Results Databases of MEDLINE, EMBASE, and the Cochrane Library were systematically searched. Clinical studies reporting the predictive value of FMD or RH‐PAT for cardiovascular events were identified. Two authors selected studies and extracted data independently. Pooled effects were calculated as risk ratio (RR) for continuous value of FMD and natural logarithm of RH‐PAT index (Ln_RHI) using random‐effects models. Thirty‐five FMD studies of 17 280 participants and 6 RH‐PAT studies of 1602 participants were included in the meta‐analysis. Both endothelial function tests significantly predicted cardiovascular events (adjusted relative risk [95% CI]: 1% increase in FMD 0.88 [0.84–0.91], P <0.001, 0.1 increase in Ln_RHI 0.79 [0.71–0.87], P <0.001). There was significant heterogeneity in the magnitude of the association across studies. The magnitude of the prognostic value in cardiovascular disease subjects was comparable between these 2 methods; a 1 SD worsening in endothelial function was associated with doubled cardiovascular risk. Conclusions Noninvasive peripheral endothelial function tests, FMD and RH‐PAT, significantly predicted cardiovascular events, with similar prognostic magnitude. Further research is required to determine whether the prognostic values of these 2 methods are independent of each other and whether an endothelial function–guided strategy can provide benefit in improving cardiovascular outcomes.