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Renovascular disease (RVD) and hypertension (HT) are cardiovascular risk factors, but if recovery of renal function can reverse cardiac dysfunction remained unclear. We hypothesized that improved stenotic kidney function would rescue myocardial microvascular (MMV) function in renovascular HT by reducing oxidative stress and inflammation. Single‐kidney hemodynamics and function and MMV permeability were assessed in pigs in vivo using CT after 6 weeks of RVD. Autologous endothelial progenitor cells (EPC) were then infused intra‐renally, and studies repeated 4 weeks later (RVD+EPC, n=7). Normal and untreated RVD (n=7 each) served as controls. Blood pressure was similarly increased in RVD and RVD+EPC pigs. Compared to normal, RVD showed elevated systemic TNF‐alpha (142.3± 3.7 vs 43.3 ± 3.5 pg/ml, p<0.001) and oxidized‐LDL, blunted glomerular filtration rate (47.9±10.1 vs 70.8 ± 4.3 ml/min, p<0.05), decreased MMV volume fraction, increased MMV permeability, and myocardial fibrosis. EPC were rarely observed in myocardium. However, RVD+EPC showed a decrease in TNF‐alpha (90.5± 2.9, p<0.01 vs RVD) and oxidized‐LDL, implying decreased inflammation and oxidative stress. Furthermore, not only renal, but also MMV function were significantly improved in RVD+EPC. In conclusion, selective improvement in renal function reduces oxidative stress and inflammation and preserves remote MMV function, underscoring functionally important cardiorenal crosstalk.

Background: The mechanisms responsible for cardiac injury in the early stage of metabolic syndrome (MetS) remain unknown. Mitochondria are intimately associated with myofibrils, where the cytoskeleton functions as a linkage coordinator. We hypothesized that early MetS is characterized by cytoskeletal-mitochondrial disorganization, and that mitoprotection with mitochondria-targeted peptides (MTP) would preserve cytoskeletal-mitochondrial structure and attenuate myocardial injury in early swine MetS. Methods: Pigs were studied after 16wks of diet-induced MetS, MetS treated for the last 4wks with the MTP Elamipretide (0.1mg/kg SC q.d), and Lean controls (n=6 each). Cardiac function (multidetector CT) was assessed in-vivo, and mitochondrial structure (electron microscopy), the mitochondrial inner membrane phospholipid cardiolipin (mass spectrometry), cytoskeletal proteins, oxidative stress, and apoptosis ex-vivo. Results: MetS pigs developed hypertension and insulin resistance, yet cardiac function was preserved. MetS induced loss of desmin and tubulin that was paralleled by mitochondrial disorganization, decreased 18:2 cardiolipin, and increased oxidative stress and apoptosis. MTP slightly improved cardiolipin species profile, restored mitochondrial organization, and upregulated cytoskeletal proteins, attenuating apoptosis and oxidative stress. Conclusion: Early MetS leads to disorganization of the cardiomyocyte cytoskeletal- mitochondrial architecture and cardiac injury. MTP may provide a novel therapeutic potential for improving cardiac injury in early MetS, and potentially preventing future deterioration in cardiac function.

Significance Statement Renal artery stenosis (RAS) engenders stenotic-kidney ischemia, dysfunction, and injury, but whether these are mediated by cellular senescence has not been elucidated. INK-ATTAC transgenic mice, high-resolution imaging, and unbiased single-cell RNA sequencing of murine kidneys demonstrated cellular senescence as an important mechanism of progressive injury to epithelial/stromal cells within poststenotic kidneys. Both p16-specific and broad quercetin/dasatinib interventions to blunt senescence improved renal function and structure, underscoring the central role of senescence in the pathogenesis. Furthermore, this mechanism was conserved in human subjects with RAS. These observations reveal new mechanisms that contribute to the pathogenesis of chronic ischemic renal injury, and support the development of senolytic therapy to reduce senescent cell burden and delay renal injury. Background Peripheral vascular diseases may induce chronic ischemia and cellular injury distal to the arterial obstruction. Cellular senescence involves proliferation arrest in response to stress, which can damage neighboring cells. Renal artery stenosis (RAS) induces stenotic-kidney dysfunction and injury, but whether these arise from cellular senescenceand their temporal pattern remain unknown. Methods Chronic renal ischemia was induced in transgenic INK-ATTAC and wild type C57BL/6 mice by unilateral RAS, and kidney function ( in vivo micro-MRI) and tissue damage were assessed. Mouse healthy and stenotic kidneys were analyzed using unbiased single-cell RNA-sequencing. To demonstrate translational relevance, cellular senescence was studied in human stenotic kidneys. Results Using intraperitoneal AP20187 injections starting 1, 2, or 4 weeks after RAS, selective clearance of cells highly expressing p16 Ink4a attenuated cellular senescence and improved stenotic-kidney function; however, starting treatment immediately after RAS induction was unsuccessful. Broader clearance of senescent cells, using the oral senolytic combination dasatinib and quercetin, in C57BL/6 RAS mice was more effective in clearing cells positive for p21 ( Cdkn1a ) and alleviating renal dysfunction and damage. Unbiased, single-cell RNA sequencing in freshly dissociated cells from healthy and stenotic mouse kidneys identified stenotic-kidney epithelial cells undergoing both mesenchymal transition and senescence. As in mice, injured human stenotic kidneys exhibited cellular senescence, suggesting this process is conserved. Conclusions Maladaptive tubular cell senescence, involving upregulated p16 ( Cdkn2a ), p19 ( Cdkn2d ), and p21 ( Cdkn1a ) expression, is associated with renal dysfunction and injury in chronic ischemia. These findings support development of senolytic strategies to delay chronic ischemic renal injury.

AbstractBackgroundWe assessed the long‐term clinical outcomes of an intermediate lesion (IL) according to the presence of a combined culprit lesion (CCL).HypothesisLong‐term clinical outcomes of IL may be affected by the presence of a CCL.MethodsAngiographic findings (n = 1096) and medical chart were reviewed. Patients with IL were divided into two groups: IL without CCL group (n = 383, 64.5%) and IL with CCL group (n = 211, 35.5%).ResultsThe major adverse cardiovascular events (MACE) in the IL with CCL group were significantly higher than those in the IL without CCL group (death: 12.3% vs. 7.0%, myocardial infarction: 3.3%vs. 0.5%, stroke: 6.6% vs. 2.6%, and revascularization [RVSC]: 25.1% vs. 7.6%) during a mean follow up period of 118.4 ± 5.5 months. IL related RVSC rate in the IL with CCL group was higher than that in the IL without CCL group (5.7% vs. 2.1%, p = 0.020). RVSC rate related to IL in total subjects was lower than that related to stented lesion (3.4% vs. 6.4%). The important predictors of total MACE in total subjects were the presence of CCL, IL percent diameter stenosis, hypertension, history of percutaneous coronary intervention, blood glucose and ejection fraction. The predictors of IL related RVSC were IL percent diameter stenosis and IL located in the right coronary artery.Conclusion10‐year clinical outcomes of an IL (especially IL without CCL) were better than those of stented lesions. This study suggests that the IL can be safely followed up in sites that do not have ability to assess functional study.

Percutaneous transluminal renal angioplasty and stenting (PTRS) for RVH may not revert the secondary cardiac dysfunction and remodeling. In experimental RVH, infusion of the tetrapeptide Bendavia (that inhibits mitochondrial permeability transition pore opening) during PTRS attenuated stenotic kidney inflammatory injury and improved its function. We hypothesized that adjunct Bendavia during PTRS would also attenuate cardiac remodeling after reversal of RVH. RVH was induced in 18 pigs, of which 6 were sham treated (RVH) and 12 underwent PTRS plus a 4h IV infusion of Bendavia (0.05 mg/kg) or vehicle (n=6, each); 6 normal pigs served as controls. Cardiac oxygenation and function were assessed 4 wks later by blood oxygen level‐dependent (BOLD)‐MRI and CT, and tissue studies performed. PTRS normalized blood pressure (Table). Systolic function was unchanged. Apoptotic activity (caspase‐3), hypoxia (BOLD‐R2*), inflammation (TNF‐α, IL‐6), and fibrosis (trichrome) remained elevated and diastolic function (E/A) impaired in PTRS+Vehicle, but all improved in PTRS+Bendavia (Figure). Thus, novel cardioprotective properties of Bendavia enhance cardiac recovery after reversal of experimental RVH, and may provide a novel therapeutic option.

Abstract Aims Circulating progenitor cells (CPCs) play a role in vascular repair and plaque stability, while osteocalcin (OC) expressing CPCs have been linked to unstable plaque and adverse cardiovascular outcomes. However, their role in cardiac allograft vasculopathy (CAV) has not been elucidated. This cohort study aimed to investigate the contribution of CPCs on CAV progression and cardiovascular events after heart transplantation. Methods and results A total of 80 heart transplant patients (mean age 55 ± 14 years, 72% male) undergoing annual intravascular ultrasound (IVUS) had fresh CPCs marked by CD34, CD133, and OC counted in peripheral blood using flow cytometry, on the same day as baseline IVUS. CAV progression was assessed by IVUS as the change (Δ) in plaque volume divided by segment length (PV/SL), adjusted for the time between IVUS measurements [median 3.0, interquartile range (2.8–3.1) years] and was defined as ΔPV/SL that is above the median ΔPV/SL of study population. Major adverse cardiac events (MACEs) were defined as any incident of revascularization, myocardial infarction, heart failure admission, re-transplantation, stroke, and death. Patients with higher CD34+CD133+ CPCs had a decreased risk of CAV progression [odds ratio 0.58, 95% confidence interval (CI) (0.37–0.92), P = 0.01] and MACE [hazard ratio (HR) 0.79, 95% CI (0.66–0.99), P = 0.05] during a median (interquartile range) follow-up of 8.0 years (7.2–8.3). Contrarily, higher OC+ cell counts were associated with an increased risk of MACE [HR 1.26, 95% CI (1.03–1.57), P = 0.02]. Conclusions Lower levels of CD34+CD133+ CPCs are associated with plaque progression and adverse long-term outcomes in patients who underwent allograft heart transplantation. In contrast, higher circulating OC+ levels are associated with adverse long-term outcomes. Thus, CPCs might play a role in amelioration of transplant vasculopathy, while OC expression by these cells might play a role in progression.

Background and Purpose: XO (xanthine oxidase) is a key enzyme of uric acid metabolism and is thought to contribute to oxidative pathways that promote atherosclerotic plaque progression, yet its role in plaque destabilization is not well elucidated. We hypothesized that XO is expressed in carotid plaque from symptomatic patients in association with cardiovascular risk factors. Methods: Patients were stratified by symptoms, defined as presentation with an ipsilateral cerebral ischemic event. Carotid atherosclerotic plaques were obtained from 44 patients with symptomatic plaque and 44 patients without ischemic cerebral events. Protein expression of XO was evaluated by immunohistochemical staining and the percentage of cells expressing XO and CD68 (macrophage marker) compared between the groups. Biochemical and demographic cardiometabolic risk factors of study participants also were measured. Results: Carotid atherosclerotic plaques from symptomatic patients were associated with significantly higher XO expression versus asymptomatic plaque (median [interquartile range]: 1.24 [2.09] versus 0.16 [0.34]; P <0.001) and with significantly higher circulating uric acid levels (mean±SD: 7.36±2.10 versus 5.37±1.79 mg/dL; P <0.001, respectively). In addition, XO expression in atherosclerotic carotid plaque was inversely associated with serum high-density lipoproteins cholesterol levels ( P =0.010, r =−0.30) and directly with circulating uric acid levels ( P <0.001, r =0.45). The average percentage of macrophages that expressed XO was significantly higher in symptomatic versus asymptomatic plaques (median [interquartile range]: 93.37% [25] versus 46.15% [21], respectively; P <0.001). Conclusions: XO overexpression in macrophages is associated with increased serum uric acid and low high-density lipoproteins cholesterol levels and may potentially have a mechanistic role in carotid plaque destabilization. The current study supports a potential role for uric acid synthesis pathway as a target for management of carotid atherosclerosis in humans.

Background: There is great degree of interobserver variability in the visual angiographic assessment of left main coronary disease (LMCD). Fractional flow reserve and intravascular ultrasound are often used in this setting. The use of instantaneous wave-free ratio (iFR) for evaluation of LMCD has not been well studied. The aim of this study is to evaluate the use of iFR in the assessment of angiographically intermediate LMCD. Methods: This is an international multicenter retrospective observational study of patients who underwent both iFR and intravascular ultrasound evaluation for angiographically intermediate LMCD. An independent core laboratory performed blinded off-line analysis of all intravascular ultrasound data. A minimum lumen area of 6 mm 2 was used as the cutoff for significant disease. Results: One hundred twenty-five patients (mean age, 68.4±9.5 years, 84.8% male) were included in this analysis. Receiver operating curve analysis showed that an iFR of ≤0.89 identified minimum lumen area <6 mm 2 with an area under the curve of 0.77 (77% sensitivity, 66% specificity; P <0.0001). Among the 69 patients without ostial left anterior descending artery or left circumflex artery disease, receiver operating curve analysis showed that an iFR of ≤0.89 identified minimum lumen area <6 mm 2 with an area under the curve of 0.84 (70% sensitivity, 84% specificity; P <0.0001). The correlation was not significantly different when the body surface area was considered. Conclusions: In this study, in patients with intermediate LMCD, iFR of ≤0.89 correlates with intravascular ultrasound minimum lumen area <6 mm 2 regardless of body surface area. The current study supports the use of iFR for the evaluation of intermediate LMCD.

Background Resistive reserve ratio (RRR), or the ratio of baseline to hyperemic microvascular resistance, has prognostic implications in predicting clinical outcomes in patients with obstructive coronary artery disease. However, its value in patients with angina or ischemia with nonobstructive coronary artery disease is unknown. Methods and Results We included 1692 patients with nonobstructive coronary artery disease who underwent invasive coronary vasoreactivity testing. Abnormal coronary flow reserve (CFR, the ratio of hyperemic and baseline resting flow velocities) and RRR were defined as <2.5 and <2.62, respectively. The mortality rate was marginally higher in patients with abnormal CFR (428 patients [25%]) than those with normal CFR (38 [9%] versus 81 [6%]; P =0.08), and was significantly higher in patients with abnormal RRR (716 patients [42%]) than those with normal RRR (70 [10%] versus 49 [5%], P =0.0002) over the median follow‐up of 11.3 years. Patients with abnormal CFR had marginally lower survival than those with normal CFR (log‐rank P =0.08). In contrast, patients with abnormal RRR had significantly lower survival than those with normal RRR (log‐rank P =0.001). Abnormal RRR was associated with shorter time to death even after adjustment for other covariates (adjusted hazard ratio, 1.63; 95% CI, 1.11–2.38; P =0.01). Conclusions In patients with no obstructive coronary artery disease, RRR was superior to CFR in predicting long‐term survival. An RRR <2.62 was associated with 1.6 times increased risk of death in patients with nonobstructive coronary artery disease. Indices of coronary microcirculatory resistive reserve comprising flow‐ and pressure‐derived values may reflect underlying microvascular pathology more faithfully than flow‐alone indices like CFR.

Introduction: Previous studies in patients with Raynaud’s phenomenon (RP) have found an association between microvascular abnormalities assessed via nail fold capillaroscopy as well as macrovascular peripheral endothelial dysfunction (PED). However, the association between RP and microvascular PED is not yet established. Hypothesis: We hypothesized that patients with RP have greater microvascular PED compared to controls without RP Methods: We performed a retrospective cross-sectional analysis of patients referred to Mayo Clinic between 2006 and 2014 for routine cardiovascular evaluation, and who underwent evaluation of Reactive Hyperemia Peripheral Arterial Tonometry (index < 2 consistent with PED). Patients with RP were identified by chart review. Results: Six hundred sixty six individuals were included in this study (mean age 51.9±13.5 years, 411 (61.3%) women), 637 (95.1%) individuals did not have RP (control group), and 29 (4.3%) had secondary RP. Only 4 patients had primary RP and were excluded from the final analyses. Individuals with secondary RP had a higher frequency of microvascular PED compared to controls ( Figure ). In a multivariate analysis adjusting for age, sex, smoking status, and use of statins we found a significant association between secondary RP and microvascular PED (OR: 2.45; 95% CI 1.13-5.34; P=0.0236) that remained significant in women after stratifying by sex. In a sensitivity analysis, we compared the frequency of PED in 29 patients with secondary RP and 58 controls matched with respect to age, sex, hypertension, dyslipidemia, and diabetes mellitus. Individuals with secondary RP had a higher frequency of microvascular PED compared to the risk factor-matched controls (18/29 [62.1%] vs 18/58 [31.0%], P=0.01). Conclusions: Secondary RP is associated with microvascular PED. Early detection of microvascular PED could help identify individuals with secondary RP who are at risk for developing cardiovascular disease.