Cardiac Function and Functional Capacity in Patients With Long COVID: A Comparison to Propensity-Matched Community Controls.

Background: Cardiac impairment has been associated with acute COVID-19 since the earliest reports of the pandemic. However, its role in postacute sequelae of COVID-19 ("long COVID") is undefined, and many existing observations about cardiovascular involvement in postacute sequelae of COVID-19 are uncontrolled.

Objective: To compare the prevalence of cardiac dysfunction in patients with long COVID and noninfected controls from the same community and explore their association with functional capacity.

Salt sensitivity risk derived from nocturnal dipping and 24-h heart rate predicts long-term blood pressure reduction following renal denervation.

Background: Renal denervation (RDN) has been consistently shown in recent sham-controlled clinical trials to reduce blood pressure (BP). Salt sensitivity is a critical factor in hypertension pathogenesis, but cumbersome to assess by gold-standard methodology. Twenty-four-hour average heart rate (HR) and mean arterial pressure (MAP) dipping, taken by ambulatory blood pressure monitoring (ABPM), stratifies patients into high, moderate, and low salt sensitivity index (SSI) risk categories.

Associations between symptoms and functional capacity in patients after COVID-19 infection and community controls.

Background: Post-acute sequelae of COVID-19 (PASC or 'long COVID') reflect ongoing symptoms, but these are non-specific and common in the wider community. Few reports of PASC have been compared with a control group.

Aims: To compare symptoms and objective impairment of functional capacity in patients with previous COVID-19 infection with uninfected community controls.

Catheter-Based Renal Denervation: 9-Year Follow-Up Data on Safety and Blood Pressure Reduction in Patients With Resistant Hypertension.

Background: Recent sham-controlled randomized clinical trials have confirmed the safety and efficacy of catheter-based renal denervation (RDN). Long-term safety and efficacy data beyond 3 years are scarce. Here, we report on outcomes after RDN in a cohort of patients with resistant hypertension with an average of ≈9-year follow-up (FU).

Prebiotic intervention with HAMSAB in untreated essential hypertensive patients assessed in a phase II randomized trial.

Fibers remain undigested until they reach the colon, where some are fermented by gut microbiota, producing metabolites called short-chain fatty acids (SCFAs), such as acetate and butyrate. SCFAs lower blood pressure in experimental models, but their translational potential is unknown. Here we present the results of a phase II, randomized, placebo-controlled, double-blind cross-over trial (Australian New Zealand Clinical Trials Registry ACTRN12619000916145) using prebiotic acetylated and butyrylated high-amylose maize starch (HAMSAB) supplementation.

Association Between the Gut Microbiome and Their Metabolites With Human Blood Pressure Variability.

Background: Blood pressure (BP) variability is an independent risk factor for cardiovascular events. Recent evidence supports a role for the gut microbiota in BP regulation. However, whether the gut microbiome is associated with BP variability is yet to be determined.

Vasoplegia Following Orthotopic Heart Transplantation: Prevalence, Predictors and Clinical Outcomes.

Background: Patients undergoing heart transplant are at high risk for postoperative vasoplegia. Despite its frequency and association with poor clinical outcomes, there remains no consensus definition for vasoplegia, and the predisposing risk factors for vasoplegia remain unclear. Accordingly, the aim of this study was to evaluate the prevalence, predictors, and clinical outcomes associated with vasoplegia in a contemporary cohort of patients undergoing heart transplantation.

Renal Deafferentation Prevents Progression of Hypertension and Changes to Sympathetic Reflexes in a Rabbit Model of Chronic Kidney Disease.

[Figure: see text].

The Gut Microbiota and Their Metabolites in Human Arterial Stiffness.

Aim: Gut microbiota-derived metabolites, such as short-chain fatty acids (SCFAs) have vasodilator properties in animal and human ex vivo arteries. However, the role of the gut microbiota and SCFAs in arterial stiffness in humans is still unclear. Here we aimed to determine associations between the gut microbiome, SCFA and their G-protein coupled sensing receptors (GPCRs) in relation to human arterial stiffness.

Leptin and Melanocortin Signaling Mediates Hypertension in Offspring From Female Rabbits Fed a High-Fat Diet During Gestation and Lactation.

Maternal high-fat diet in rabbits leads to hypertension and elevated renal sympathetic nerve activity (RSNA) in adult offspring but whether this is due to adiposity or maternal programming is unclear. We gave intracerebroventricular (ICV) and ventromedial hypothalamus (VMH) administration of leptin-receptor antagonist, α-melanocyte-stimulating hormone (αMSH), melanocortin-receptor antagonist (SHU9119), or insulin-receptor (InsR) antagonist to conscious adult offspring from mothers fed a high-fat diet (mHFD), control diet (mCD), or mCD offspring fed HFD for 10d (mCD10d, to deposit equivalent fat but not during development). mHFD and mCD10d rabbits had higher mean arterial pressure (MAP, +6.

Contribution of the Renal Nerves to Hypertension in a Rabbit Model of Chronic Kidney Disease.

Overactivity of the sympathetic nervous system and high blood pressure are implicated in the development and progression of chronic kidney disease (CKD) and independently predict cardiovascular events in end-stage renal disease. To assess the role of renal nerves, we determined whether renal denervation (RDN) altered the hypertension and sympathoexcitation associated with a rabbit model of CKD. The model involves glomerular layer lesioning and uninephrectomy, resulting in renal function reduced by one-third and diuresis.

Differential sympathetic response to lesion-induced chronic kidney disease in rabbits.

Chronic kidney disease (CKD) is associated with greater sympathetic nerve activity but it is unclear if this is a kidney-specific response or due to generalized stimulation of sympathetic nervous system activity. To determine this, we used a rabbit model of CKD in which quantitative comparisons with control rabbits could be made of kidney sympathetic nerve activity and whole-body norepinephrine spillover. Rabbits either had surgery to lesion 5/6 of the cortex of one kidney by electro-lesioning and two weeks later removal of the contralateral kidney, or sham lesioning and sham nephrectomy.

The Emerging Role of Gut Dysbiosis in Cardio-metabolic Risk Factors for Heart Failure.

Purpose Of Review: To summarize the recent evidence that supports a role for the gut microbiota, microbiota-derived metabolites, and dysbiosis on cardiovascular risk factors, and to discuss the neuro-cardio-metabolic mechanisms that link gut microbiota and heart failure.

Recent Findings: There is growing evidence that the gut microbiota communicates with and impacts the cardiovascular system, contributing to the development of heart failure once it becomes out of balance (i.e.

Empagliflozin modulates renal sympathetic and heart rate baroreflexes in a rabbit model of diabetes.

Aims/hypothesis: We determined whether empagliflozin altered renal sympathetic nerve activity (RSNA) and baroreflexes in a diabetes model in conscious rabbits.

Methods: Diabetes was induced by alloxan, and RSNA, mean arterial pressure (MAP) and heart rate were measured before and after 1 week of treatment with empagliflozin, insulin, the diuretic acetazolamide or the ACE inhibitor perindopril, or no treatment, in conscious rabbits.

Results: Four weeks after alloxan administration, blood glucose was threefold and MAP 9% higher than non-diabetic controls (p < 0.

Threshold and saturation pressures of baroreflex-mediated myocardial interstitial acetylcholine release in rats.

Cardiac microdialysis allows the assessment of cardiac efferent vagal nerve activity from myocardial interstitial acetylcholine (ACh) levels with minimal influence on the neural control of the heart; however, a total picture of the baroreflex-mediated myocardial interstitial ACh release including the threshold and saturation pressures has yet to be quantified. In eight anesthetized Wistar-Kyoto rats, we implanted microdialysis probes in the left ventricular free wall and measured the myocardial interstitial ACh release simultaneously with efferent sympathetic nerve activity (SNA) during a carotid sinus baroreceptor pressure input between 60 and 180 mm Hg. The baroreflex-mediated ACh release approximated a positive sigmoid curve, and its threshold and saturation pressures were not significantly different from those of an inverse sigmoid curve associated with the baroreflex-mediated SNA response (threshold: 94.

Moderate morning rise in blood pressure has lowest risk of stroke but only in women.

Background: The morning period which is recognized as the highest risk for cardiovascular events is associated with a surge in blood pressure (BP). However, it is unclear what aspect of this rise is important.

Aim: To determine whether the rate of rise (RoR), the magnitude (day night difference) or the product [BP power (BPPower)] is associated with increased cardiovascular risk.

Successful renal denervation decreases the platelet activation status in hypertensive patients.

Aims: To determine whether renal denervation (RDN) in hypertensive patients affects the platelet activation status.

Methods And Results: We investigated the effect of RDN on the platelet activation status in 41 hypertensive patients undergoing RDN. Ambulatory blood pressure (BP), plasma sympathetic neurotransmitter Neuropeptide Y, and platelet activation markers were measured at baseline, at 3 months, and 6 months after RDN.

Role of the Sympathetic Nervous System and Its Modulation in Renal Hypertension.

The kidneys are densely innervated with renal efferent and afferent nerves to communicate with the central nervous system. Innervation of major structural components of the kidneys, such as blood vessels, tubules, the pelvis, and glomeruli, forms a bidirectional neural network to relay sensory and sympathetic signals to and from the brain. Renal efferent nerves regulate renal blood flow, glomerular filtration rate, tubular reabsorption of sodium and water, as well as release of renin and prostaglandins, all of which contribute to cardiovascular and renal regulation.

Ambulatory arterial stiffness index as a predictor of blood pressure response to renal denervation.

Background: Renal denervation (RDN) can reduce blood pressure (BP) in patients with resistant hypertension, but less so in patients with isolated systolic hypertension. A possible explanation is that patients with stiffer arteries may have lesser neural contribution to their hypertension.

Method: We hypothesized that arterial stiffness predicts the response to RDN.

Factors Responsible for Obesity-Related Hypertension.

Purpose Of Review: The major health issue of being overweight or obese relates to the development of hypertension, insulin resistance and diabetic complications. One of the major underlying factors influencing the elevated blood pressure in obesity is increased activity of the sympathetic nerves to particular organs such as the kidney.

Recent Findings: There is now convincing evidence from animal studies that major signals such as leptin and insulin have a sympathoexcitatory action in the hypothalamus to cause hypertension.

Acute Effect of Central Administration of Urotensin II on Baroreflex and Blood Pressure in Conscious Normotensive Rabbits.

In the present study, we examined the effects of central administration of Urotensin II on blood pressure, heart rate, and baroreceptor heart rate reflexes in conscious normotensive rabbits. Preliminary operations were undertaken to implant a balloon cuff on the inferior vena cava for baroreflex assessments and to implant cannula into the lateral and fourth ventricle. After 2 weeks of recovery cumulative dose response curves to Urotensin II (10, 100 ng, 1, 10, and 100 μg) given into the ventricles, or Ringer's solution as a vehicle were performed on separate days.

Effect of renal denervation on kidney function in patients with chronic kidney disease.

Aims: Renal denervation (RDN) can reduce blood pressure (BP) and slow the decline of renal function in chronic kidney disease (CKD) up to one year. Whether this effect is maintained beyond 12months and whether the magnitude of BP reduction affects estimated glomerular filtration rate (eGFR) is unknown.

Methods And Results: We examined eGFR in 46 CKD patients (baseline eGFR ≤60mL/min/1.