Interventional management of mitral regurgitation and sleep disordered breathing: "Catching two birds with one stone".

Sleep disordered breathing (SDB), mostly constituting of obstructive and central sleep apnea (OSA and CSA, respectively), is highly prevalent in the general population, and even more among patients with cardiovascular disease, heart failure (HF) and valvular heart disease, such as mitral regurgitation (MR). The coexistence of HF, MR and SDB is associated with worse cardiovascular outcomes and increased morbidity and mortality. Pulmonary congestion, as a result of MR, can exaggerate and worsen the clinical status and symptoms of SDB, while OSA and CSA, through various mechanisms that impair left ventricular dynamics, can promote left ventricular remodelling, mitral annulus dilatation and consequently MR. Regarding treatment, positive airway pressure devices used to ameliorate symptoms in SDB also seem to result in a reduction of MR severity, MR jet fraction and an improvement of left ventricular ejection fraction. However, surgical and transcatheter interventions for MR, and especially transcatheter edge to edge mitral valve repair (TEER), seem to also have a positive effect on SDB, by reducing OSA and CSA-related severity indexes and improving symptom control. The purpose of this review is to provide a comprehensive analysis of the common pathophysiology between SDB and MR, as well as to discuss the available evidence regarding the effect of SDB treatment on MR and the effect of mitral valve surgery or transcatheter repair on both OSA and CSA.

Intravascular Imaging in Ultra-Low or Zero-Contrast Percutaneous Coronary Interventions: The Time Is Now?

Ultra-low contrast percutaneous coronary interventions (ULPCIs) are a novel field of interventional cardiology, aiming to reduce the risk of contrast-induced nephropathy (CIN), which is a well-described adverse event after angiography. CIN is a well-described adverse event following PCI, especially in high-risk patients, i.e., patients with an already deteriorating renal function or chronic kidney disease, as well as patients of advanced age or requiring an increased amount of contrast during their intervention. Among the techniques described for ULPCI procedures, intravascular imaging guidance seems a promising option, as it allows lesion recognition and characterization, stent implantation, and PCI optimization. Intravascular ultrasound (IVUS) is the modality most commonly used, as it does not require contrast injection, contrary to optical coherence tomography (OCT). Several clinical trials, assessing IVUS in the context of ULPCI, have shown that it can be safely used in this setting while offering a substantial reduction in contrast media volume, as well as renal adverse outcomes. This review aims to describe the need for ULPCI and technical considerations regarding the use of intravascular imaging in this setting, as well as analyze the available evidence from clinical trials regarding the safety and efficacy of IVUS-ULPCI, in order to provide a comprehensive summary for practicing physicians.

Transfemoral transcatheter aortic valve replacement in the presence of a mitral prosthesis.

PURPOSE: In the current case series, we present our experience with the self-expanding CoreValve or Evolut R (Medtronic Inc.) in patients with severe symptomatic aortic valve stenosis and concomitant mitral valve prosthesis. METHODS: Twelve patients with previous mitral valve prosthesis underwent transcatheter aortic valve replacement for severe symptomatic aortic valve stenosis and/or aortic valve regurgitation. All patients underwent evaluation with an echocardiogram, computed tomography and coronary angiogram. After the index intervention and before discharge all patients underwent transthoracic echocardiography. All outcomes were defined according to the Valve Academic Research Consortium-2 criteria. RESULTS: Eleven patients underwent transcatheter aortic valve replacement for severe symptomatic aortic valve stenosis and one patient for severe aortic valve regurgitation. There was immediate improvement of patients' hemodynamic status; no cases of procedural death, stroke, myocardial infarction, or urgent cardiac surgery occurred. There was no 30-day mortality and all patients improved, with 91.6% in functional New York Heart Association class I-II. CONCLUSION: The current study demonstrates that in patients with severe aortic valve stenosis or regurgitation and mitral valve prosthesis, the implantation of a self-expanding aortic valve via the transfemoral route is safe and feasible, with maintained long-term results.

Inhibition of Aortic Valve Calcification by Local Delivery of Zoledronic Acid-an Experimental Study.

The aim of this study was to evaluate in an experimental model of aortic valve (AV) stenosis the effectiveness of zoledronate on the inhibition of calcification. Sixteen New Zealand rabbits were placed on vitamin D-enriched diet for 3 weeks. All animals underwent PET/CT at baseline and before euthanasia to assess calcification. Thereafter, the AVs of eight animals were treated with local delivery of 500 µg/l zoledronate. A placebo mixture was administered in the remaining eight animals. Standardized uptake values were corrected for blood pool activity, providing mean tissue to background ratios (TBRmean). In the zoledronate group, there was no progression of AV calcification (TBRmean 1.20 ± 0.12 vs 1.17 ± 0.78,p = 0.29), while AV calcification progressed in the placebo group (1.22 ± 0.15 vs 1.53 ± 0.23,p = 0.006). Ascending aorta (AA) calcification progressed in both zoledronate and placebo groups. Histology confirmed the results of the PET/CT. Inhibition of AV calcification by local delivery of zoledronate is feasible and effective.

Long-term endothelial dysfunction after trans-radial catheterization: A meta-analytic approach.

BACKGROUND: Following cardiac catheterization using radial artery (RA) access, persistent endothelial dysfunction may limit the use of RA as a conduit during coronary artery bypass graft (CABG) surgery. We reviewed published literature to investigate the effects of transradial coronary catheterization on RA endothelial function. METHODS: We searched PubMed from inception to April 2017 for published studies assessing RA endothelial function late (≥1 month) after coronary catheterization. A total of 12 eligible published studies (n = 490 patients) were included in the final quantitative synthesis. Statistical heterogeneity among studies was assessed by the I2 . A random effects model was used to calculate the pooled estimate for standardized mean difference (SMD). Meta-regression analysis was used to explore predictors of change in RA endothelial function following catheterization. RESULTS: In all studies, a significant reduction in endothelium dependent response was observed post-catheterization (SMD = -0.53, 95% confidence interval [CI]: -0.93 to -0.13, P = 0.01) and a marginal, non-significant, reduction in endothelium independent response (SMD = -0.38, 95%CI: -0.77, 0.01, P < 0.059). In controlled studies, using the contralateral RA as a control, a significant impairment in endothelial function was confirmed (SMD = -6.26, 95%CI: -9.71 to -2.81, P < 0.0001), while the change in endothelium-independent response was not significant (SMD = -4.46, 95%CI: -13.3 to 4.37, P = 0.32). In meta-regression analysis male gender (z = 2.36, P = 0.018) and increasing time following catheterization (z = 2.62, P = 0.009) were associated with less RA endothelial dysfunction. CONCLUSIONS: Transradial catheterization impairs endothelium dependent vasodilatory properties of the cannulated RA, which do not recover even several months post-catheterization. Non-recovery of vasomotor function of cannulated RAs may limit their use as arterial grafts during CABG surgery.

Therapeutic Applications of Calcium Metabolism Modulation in Heart Disease.

Cardiovascular disease is the leading cause of death worldwide and there is extensive research on the pathophysiology of all its clinical entities. Despite the big array of possible therapeutic modalities for cardiovascular disease, there is still a big necessity to develop novel treatments that will augment our strategies for tackling the burden of cardiovascular disease and decrease morbidity and mortality. A major player in both the physiology and pathophysiology of the cardiovascular system is calcium. Extracellular calcium is required in order to initiate cardiac muscle contraction and promote the calcium-induced calcium release mechanism from the sarcoplasmic reticulum. A lot of molecules and structures that in a direct or indirect way interact with calcium are being studied and there is a constant flow of new information that is emerging. In this review we focus on some of these calcium metabolism modulators representatives such as SERCA2a, RyR2, S100A1, phosholamban and calcineurin. We emphasize on their mechanism of action, their role in cardiovascular disease and potential therapeutic implications. We also focus on the effect the bisphosphonates might have in regression of the calcium deposition in the human arteries as well as the usage of novel biomarkers such as mircoRNAs in calcium metabolism modulation in heart disease.