Denerwacja tętnic nerkowych w leczeniu niewydolności serca

Radio-frequency renal denervation (RF-RND) was introduced as an invasive method to treat patient with resistant hypertension. It seems that RF-RND has a potential to treat patients with heart failure. The initial studies proved its efficacy to reduce heart failure symptoms, to increase left ventricle ejection fraction and to reduce episodes of ventricular arrhythmias. However, results presented so far concerned only a small group of patients. Thus large ongoing clinical trials will give final conclusions about the RF-RND application in heart failure treatment.Przezskórna denerwacja tętnic nerkowych została wprowadzona jako metoda inwazyjnego leczenia pacjentów z opornym nadciśnieniem tętniczym. Wydaje się, że metoda ta ma również potencjał w leczeniu pacjentów z niewydolnością serca. Wstępne obserwacje kliniczne potwierdziły jej skuteczność w poprawie kurczliwości lewej komory serca, redukcji objawów i częstości występowania epizodów arytmii komorowej. Niestety, obserwacje te były przeprowadzone na nielicznej grupie pacjentów i dopiero wyniki aktualnie prowadzonych badań pozwolą jednoznacznie ocenić skuteczność tej metody w leczeniu pacjentów z niewydolnością serca

The co-application of hypoxic preconditioning and postconditioning abolishes their own protective effect on systolic function in human myocardium

Background: Ischemic preconditioning (IPC) and postconditioning (POC) are well documented to trigger cardioprotection against ischemia/reperfusion (I/R) injury, but the effect oftheir both co-application remains unclear in human heart. The present study sought to assessthe co-application of IPC and POC on fragments of human myocardium in vitro.Methods: Muscular trabeculae of the human right atrial were electrically driven in the organbath and subjected to simulated I/R injury – hypoxia/re-oxygenation injury in vitro. To achieveIPC of trabeculae the single brief hypoxia period preceded the applied lethal hypoxia, and to achieve POC triple brief hypoxia periods followed the lethal hypoxia. Additional muscular trabeculae were exposed only to the hypoxic stimulation (Control) or were subjected to the non-hypoxic stimulation (Sham). 10 μM norepinephrine (NE) application ended every experiment to assess viability of trabeculae. The contraction force of the myocardium assessed as a maximal amplitude of systolic peak (%Amax) was obtained during the whole experiment’s period.Results: Co-application of IPC and POC resulted in decrease in %Amax during the re-oxygentaionperiod and after NE application, as compared to Control (30.35 ± 2.25 vs. 41.89 ± 2.25, 56.26 ± 7.73 vs. 65.98 ± 5.39, respectively). This was in contrary to the effects observed when IPC and POC were applied separately.Conclusions: The co-application of IPC and POC abolishes the cardioprotection of either intervention alone against simulated I/R injury in fragments of the human right heart atria

‘Opioidergic postconditioning’ of heart muscle during ischemia/reperfusion injury

  Background: Ischemic preconditioning and postconditioning are the novel strategies of attaining cardioprotection against ischemia/reperfusion (I/R) injury. Previous studies suggested the role of opioid pathway, however the class of opioid receptors responsible for this effect in humans remains unknown. The aim of the study was to assess the influence of opioids on simulated I/R injury outcomes in the hu­man myocardium. Methods: Trabeculae of the human right atrium were electrically driven in organ bath and subjected to simulated I/R injury. Morphine (10–4M, 10–5M, 10–6M) or d-opioid receptor agonist DADLE (10–8M, 10–7M, 10–6M) was used at the time of re-oxygenation. Additional trabecula was subjected to hypoxia protocol only (Control). Contractive force of the myocardium was assessed as the maximal force of a contraction (Amax), the rate of rise of the force of a contraction (Slope L) and relaxation as the rate of decay of the force of a contraction (Slope T). Results: Application of morphine 10–4M resulted in increase of Amax, Slope L and Slope T during re-oxygenation period as compared to Control (77.99 ± 1.5% vs. 68.8 ± 2.2%, p < 0.05; 45.72 ± 2.9% vs. 34.12 ± 5.1%, p < 0.05; 40.95 ± 2.5% vs. 32.37 ± 4.3%, p < 0.05). Parameters were not significantly different in the lower morphine concentrations. Application of DADLE 10–6M resulted in decrease of Amax and Slope L as compared to Control (68.13 ± 5.5% vs. 76.62 ± 6.6%, p < 0.05; 28.29 ± 2.2 vs. 34.80 ± 3.9%, p < 0.05). Conclusions: At re-oxygenation, morphine improves systolic and diastolic function of the human myo­cardium in the dose-dependent manner. Delta-opioid receptor stimulation attenuates systolic function of human heart muscle which remains in contrast to previous reports with animal models of I/R injury. (Cardiol J 2017; 24, 4: 419–425

Multimodality imaging of intermediate lesions: Data from fractional flow reserve, optical coherence tomography, near-infrared spectroscopy-intravascular ultrasound

  Background: Fractional flow reserve (FFR) assesses a functional impact of the atheroma on the myocardial ischemia, but it does not take into account the morphology of the lesion. Previous optical coherence tomography (OCT), intravascular ultrasound (IVUS) and near-infrared spectroscopy (NIRS) studies presented their potential to detect vulnerable plaques, which is not possible by FFR assessment. With the following study, the intermediate lesions were assessed by FFR, OCT and combined NIRS-IVUS imaging to identify plaque vulnerability. Methods: Thirteen intermediate lesions were analyzed simultaneously by FFR, OCT and combined NIRS-IVUS imaging. Results: Two lesions were found to have FFR ≤ 0.80 (0.65 and 0.76). The other 11 lesions had FFR > 0.80 with a mean FFR 0.88 ± 0.049. Two lesions with FFR ≤ 0.80 had plaque burden (PB) > 70% and minimal lumen area (MLA) < 4 mm2, but neither of these 2 lesions were identified as OCT de­fined thin fibrous cap atheroma (TCFA), or NIRS-IVUS possible TCFA. Among the other 11 lesions with FFR > 0.80, 8 were identified as OCT-defined TCFA, 4 had PB > 70%, 6 had MLA < 4 mm2, 2 had both PB > 70% and MLA < 4 mm2, 3 lesions were identified as NIRS-IVUS possible TCFA, and 4 lesions had lipid core burden index > 400. Conclusions: The FFR-negative lesions pose traits of vulnerability as assessed simultaneously by IVUS, OCT and NIRS imaging.

Biodegradable polymer-coated thin strut sirolimus- -eluting stent versus durable polymer-coated everolimus-eluting stent in the diabetic population

Background: The number of patients with diabetes mellitus (DM) presenting with coronary artery disease is increasing and accounts for more than 30% of patients undergoing percutaneous coronary interventions (PCI). The biodegradable polymer drug-eluting stents were developed to improve vascular healing. It was sought herein, to determine 1-year clinical follow-up in patients with DM treated with the thin strut biodegradable polymer-coated sirolimus-eluting stent (BP-SES) versus durable coating everolimus-eluting stent (DP-EES).Methods: Patients were retrospectively analyzed with DM were treated with either a BP-SES (ALEX™, Balton, Poland, n = 670) or a DP-EES (XIENCE™, Abbott, USA, n = 884) with available 1 year clinical follow-up using propensity score matching. Outcomes included target vessel revascularization (TVR) as efficacy outcome and all-cause death, myocardial infarction, and definite/probable stent thrombosis as safety outcomes.Results: After propensity score matching 527 patients treated with BP-SES and 527 patients treated with DP-EES were selected. Procedural and clinical characteristics were similar between both groups. In-hospital mortality was 3.23% in BP-SES vs. 2.09% in DP-EES group (p = 0.25). One-year followup demonstrated comparable efficacy outcome TVR (BP-SES 6.64% vs. DP-EES 5.88%; p = 0.611), as well as similar safety outcomes of all-cause death (BP-SES 10.06% vs. DP-EES 7.59%; p = 0.158), myocardial infarction (BP-SES 7.959% vs. DP-EES 6.83%; p = 0.813), and definite/probable stent thrombosis (BP-SES 1.14% vs. DP-EES 0.76%; p = 0.525).Conclusions: The thin-strut biodegradable polymer coated, sirolimus-eluting stent demonstrated comparable clinical outcomes at 1-year after implantation to DP-EES. These data support the relative safety and efficacy of BP-SES in diabetic patients undergoing PCI

First experimental evidence of the piezoelectric nature of struvite

In this paper, we present the first experimental evidence of the piezoelectric nature of struvite ( MgNH4PO4·6H2O). Using a single diffusion gel growth technique, we have grown struvite crystals in the form of plane parallel plates. For struvite crystals of this shape, we measured the piezoelectric coefficients d33 and d32. We have found that at room temperature the value of piezoelectric coefficient d33 is 3.5 pm/V, while that of d32 is 4.7 pm/V. These values are comparable with the values for other minerals. Struvite shows stable piezoelectric properties up to the temperature slightly above 350 K, for the heating rate of 0.4 K/min. For this heating rate, and above this temperature, the thermal decomposition of struvite begins, which, consequently, leads to its transformation into dittmarite with the same non-centrosymmetric symmetry as in case of struvite. The struvite-dittmarite transformation temperature is dependent on the heating rate. The higher the heating rate, the higher the temperature of this transformation. We have also shown that dittmarite, like struvite exhibits piezoelectric properties

Atherosclerotic plaque burden distribution in the coronary arteries. The myocardial bridging effect

Mimo że czynniki ryzyka mają charakter ogólnoustrojowy, to rozmieszczenie zwapnień i blaszek miażdżycowych nie jest przypadkowe. Co więcej, zmiany w gałęzi przedniej zstępującej (LAD) występują częściej niż w prawej tętnicy wieńcowej. Najrzadziej w gałęzi okalającej (CX) i pniu lewej tętnicy wieńcowej, przy czym w LAD i CX rozmieszczenie zmian skupia się w początkowych odcinkach tych tętnic. Ogniskowy charakter rozmieszczenia blaszki wskazuje, że lokalne czynniki hemodynamiczne mogą brać udział w zapoczątkowaniu i progresji miażdżycy. W artykule omówiono topografię zmian miażdżycowych w odniesieniu do rozkładu naprężeń ścinających. Przedstawiono hipotezę, zgodnie z którą większa częstość występowania zmian w początkowym odcinku LAD może się wiązać z występowaniem przepływów wstecznych w gałęzi przedniej zstępującej w efekcie skurczowego zaciskania światła gałęzi septalnych.Despite the fact that risk factors are systemic in nature, calcifications and atherosclerosis do not occur at random. Plaques are located mostly in the left anterior descending artery (LAD), then in the right coronary artery, circumflex branch (LCx) and the left main coronary artery, in a decreasing order of frequency. In the LAD and LCx, plaques tend to cluster within the proximal segment. The focal nature of plaque formation indicates that local hemodynamic forces could be involved in the initiation and development of atherosclerosis. The aim of this review was to discuss plaque distribution in relation to hemodynamic factors as oscillatory shear stress. We present the hypothesis that proximal LAD predisposition for atherosclerosis can be linked to the septal branches. Its major course runs within the muscle and the systolic compression of the septal perforator (milking effect) can disturb blood flow patterns with flow reversal in the atherosclerosis-prone LAD segment

Safety and efficacy of embolic protection devices in saphenous vein graft interventions : a propensity score analysis-multicenter SVG PCI PROTECTA study

Background: Evidence concerning the efficacy of the embolic protection devices (EPDs) in saphenous vein graft (SVG) percutaneous coronary intervention (PCI) is sparse. The study was designed to compare major cardiovascular events of all-comer population of SVG PCI with and without EPDs at one year of follow-up. Methods and results: A multi-center registry comparing PCI with and without EPDs in consecutive patients undergoing PCI of SVG. The group comprised 792 patients, among which 266 (33.6%) had myocardial infarction (MI). The primary composite endpoint was major adverse cardiac and cerebrovascular event (MACCE) defined as death, MI, target vessel revascularization (TVR), and stroke assessed at one year. After propensity score analysis, there were no differences in MACCE (21.9% vs. 23.9%; HR 0.91, 95% CI 0.57–1.45, p = 0.681, respectively) nor in secondary endpoints of death, MI, TVR, target lesion revascularization (TLR) and stroke at one year in EPDs PCI group vs. no-EPDs PCI group. Similarly, there were no differences between groups in the study endpoints at 30 days follow-up. Conclusions: There were no clinical benefit for routine use of EPDs during SVG PCI in short and long-term follow-up. Further studies are warranted to explore the effect of individual types of EPDs on clinical outcomes