11 research outputs found
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
Coronary plaque redistribution after stent implantation is determined by lipid composition: A NIRS-IVUS analysis
Background: The composition of plaque impacts the results of stenting. The following study evaluated plaque redistribution related to stent implantation using combined near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) imaging.
Methods: The present study included 49 patients (mean age 66 ± 11 years, 75% males) presenting with non-ST elevation myocardial infarction (8%), unstable angina (49%) and stable coronary artery disease (43%). The following parameters were analyzed: mean plaque volume (MPV, mm3), plaque burden (PB, %), remodeling index (RI), and maximal lipid core burden index in a 4 mm segment (maxLCBI4mm). High-lipid burden lesions (HLB) were defined as by maxLCBI4mm > 265 with positive RI. Otherwise plaques were defined as low-lipid burden lesions (LLB). Measurements were done in the target lesion and in 4 mm edges of the stent before and after stent implantation.
Results: MPV and maxLCBI4mm decreased in both HLB (MPV 144.70 [80.47, 274.25] vs. 97.60 [56.82, 223.45]; maxLCBI4mm: 564.11 ± 166.82 vs. 258.11 ± 234.24, p = 0.004) and LLB (MPV: 124.50 [68.00, 186.20] vs. 101.10 [67.87, 165.95]; maxLCBI4mm: 339.07 ± 268.22 vs. 124.60 ± 160.96, p < 0.001), but MPV decrease was greater in HLB (28.00 [22.60, 57.10] vs. 13.50 [1.50, 28.84], p = 0.019). Only at the proximal stent edge of LLB, maxLCBI4mm decreased (34 [0, 207] vs. 0 [0, 45], p = 0.049) and plaque burden increased (45.48 [40.34, 51.55] vs. 51.75 [47.48, 55.76], p = 0.030).
Conclusions: NIRS-IVUS defined HLB characterized more significant decreases in plaque volume by stenting. Plaque redistribution to the proximal edge of the implanted stent occurred only in LLB
Comparison of the short-term safety and efficacy of transcarotid and transfemoral access routes for transcatheter aortic valve implantation
Background: Transfemoral access is the preferred approach for transcatheter aortic valve implantation (TAVI), as it is characterized by the lowest complication rate. In the majority of patients ineligible for transfemoral access, the transcarotid approach can be used.
Aims: This study aimed to compare short‑term outcomes in 2 groups of patients treated with transcarotid or transfemoral TAVI.
Methods: A retrospective comparison included 265 patients in whom the TAVI procedure was performed between 2017 and 2019 (transcarotid TAVI, n = 33; transfemoral TAVI, n = 232). Preoperative characteristics, procedural and postprocedural outcomes, as well as 30‑day mortality were assessed.
Results: Compared with the transfemoral TAVI group,patients undergoing transcarotid TAVI presented with a higher New York Heart Association (NYHA) functional class (median [interquartile range (IQR)], 3 [3–3] vs 2 [2–3]; P < 0.001), a higher surgical risk (median [IQR] EuroSCORE II, 6 [4.8–10.7] vs 4.8 [2.8–7.9]; P = 0.003), and a higher incidence of peripheral artery disease (36.4% vs 18.1%; P = 0.035). The median (IQR) procedure duration in the transcarotid TAVI group was shorter than in patients undergoing transfemoral TAVI (65 [60–80] min vs 90 [80–110] min; P < 0.001, respectively). In both study groups, we noted a high percentage of procedural success (transcarotid vs transfemoral TAVI, 96.9% vs 97.2%; P = 0.66). We found no significant differences between transcarotid TAVI and transfemoral TAVI in terms of periprocedural and 30‑day mortality as well as the number of strokes. Regardless of the access route chosen, echocardiographic parameters and the NYHA class similarly improved compared with preprocedural data.
Conclusions: Despite posing a higher baseline risk and presenting a greater anatomic complexity, transcarotid access is safe and associated with 30‑day outcomes similar to those observed for transfemoral access. Importantly, procedural time was short and no periprocedural strokes or vascular complications were reported
Procedural Tools and Technics for Transcatheter Paravalvular Leak Closure: Lessons from a Decade of Experience.
Prosthetic paravalvular leaks (PVLs) are associated with congestive heart failure and hemolysis. Surgical PVL closure carries high risks. Transcatheter implantation of occluding devices in PVL is a lower risk but challenging procedure. Of the available devices, only two have been specifically approved in Europe for transcatheter PVL closure (tPVLc): the Occlutech® Paravalvular Leak Device (PLD) and Amplatzer™ ParaValvular Plug 3 (AVP 3). Here, we review the various tools and devices used for tPVLc, based on three observational registries including 748 tPVLc procedures performed in 2005-2021 at 33 centres in 11 countries. In this case, 12 registry investigators with over 20 tPVLc procedures each described their practical tips and tricks regarding imaging, approaches, delivery systems, and devices. They considered three-dimensional echocardiography to be the cornerstone of PVL assessment and procedure guidance. Anterograde trans-septal mitral valve and retrograde aortic approaches were used in most centres, although some investigators preferred the transapical approach. Hydrophilic-coated low-profile sheaths were used most often for device deployment. The AVP 3 and PLD devices were chosen for 89.0% of procedures. Further advances in design and materials are awaited. These complex procedures require considerable expertise, and experience accumulated over a decade has no doubt contributed to improve practices