Early Cardiac Rehabilitation Improves Carotid Arterial Stiffness in Patients with Myocardial Infarction

Bogus&lstrok;awa O&lstrok;pi&nacute;ska,1 Rafa&lstrok; Wyderka,1,2 Maria &Lstrok;oboz-Rudnicka,1 Barbara Brzezi&nacute;ska,1 Krystyna &Lstrok;oboz-Grudzie&nacute;,1 Joanna Jaroch1,2 1Department of Cardiology, T Marciniak Lower Silesian Specialist Hospital, Emergency Medicine Center, Wroc&lstrok;aw, Poland; 2Faculty of Medicine, University of Science and Technology, Wroc&lstrok;aw, PolandCorrespondence: Bogus&lstrok;awa O&lstrok;pi&nacute;ska, Department of Cardiology, T Marciniak Lower Silesian Specialist Hospital, Emergency Medicine Center, Ul. Genera&lstrok;a Augusta Fieldorfa 2, Wroc&lstrok;aw, 54-049, Poland, Email [email protected]: Little is known about the effect of cardiac rehabilitation (CR) on carotid arterial stiffness (CAS) in patients with myocardial infarction (MI).Patients and Methods: Rehabilitation group (B) included 90 patients with MI subjected to CR, control group (K) consisted of 30 patients with MI not participating in CR, and healthy group comprised 38 persons without cardiovascular risk factors. CAS was determined using echo-tracking before and after CR.Results: At baseline, patients with MI (B+K) presented with significantly higher mean values of CAS parameters: beta-stiffness index (7.1 vs 6.4, p = 0.004), Peterson’s elastic modulus (96 kPa vs 77 kPa, p < 0.001) and PWV-beta (6.1 m/s vs 5.2 m/s, p < 0.001) than healthy persons. Age (beta: r = 0.242, p = 0.008; EP: r = 0.250, p = 0.006; PWV-beta: r = 0.224, p = 0.014) and blood pressure: SBP (EP: r = 0.388, PWV-beta: r = 0.360), DBP (AC: r = 0.225) and PP (PWV-beta: r = 0.221) correlated positively with the initial parameters of CAS. Beta-stiffness index (Rho=− 0.26, p = 0.04) and PWV-beta (Rho = 0.29, p = 0.03) correlated inversely with peak exercise capacity expressed in METs. After CR, mean values of beta-stiffness index (6.2 vs 7.1, p = 0.016), EP (78 kPa vs 101 kPa, p = 0.001) and PWV-beta (5.4 m/s vs 6.2 m/s, p = 0.001) in group B were significantly lower than in group K. In group B, CAS parameters decreased significantly after CR. Univariate analysis demonstrated that the likelihood of an improvement in CAS after CR was significantly higher in patients with baseline systolic blood pressure < 120 mm Hg (OR = 2.74, p = 0.009) and left ventricular ejection fraction < 43% (OR = 5.05, p = 0.005).Conclusion: In patients with MI, CR exerted a beneficial effect on CAS parameters. The improvement in CAS was predicted by lower SBP and LVEF at baseline.Keywords: carotid arterial stiffness, managed care after myocardial infarction, acute coronary syndrome, echo-trackin

Analysis of impulse current distribution in lightning protection system and connected installations

W artykule przedstawiono poligon badawczy systemów ochrony odgromowej należący do Politechniki Rzeszowskiej. Przeprowadzono badania rozpływu prądów udarowych w urządzeniu piorunochronnym obiektu budowlanego i dołączonej instalacji. W badaniach wykorzystano mobilny generator udarów prądowych i oryginalny system pomiarowy. Uzyskane wyniki potwierdzają rejestracje dokonane na Florydzie z wykorzystaniem wyładowań atmosferycznych prowokowanych. Kształty fal prądowych nie są jednakowe w różnych miejscach badanego układu i zależą od parametrów częstotliwościowych poszczególnych elementów instalacji, natomiast efektywność odprowadzania prądu piorunowego do ziemi przez urządzenie piorunochronne zależy od relacji między wartościami impedancji uziemienia obiektu budowlanego i uziemienia najbliższej stacji transformatorowej.The paper presents a new test site of lightning protection systems belonging to the Rzeszow University of Technology. Analysis of impulse current distribution in the lightning protection system and the connected installations has been conducted. An impulse current generator was used together with the original measurement system during experimental tests. Obtained results confirm registrations made in Florida with usage of triggered lightning experiments. Current waveforms are not the same in lightning protection system and are influenced by frequency dependent parameters of different parts of the installation. The effectiveness of lightning protection system depends on the relation between the amount of impedances of the local grounding system and the grounding system of the transformer station