Alvydas Unikauskas

Applicability of Impedance Cardiography During Heart Failure Flare-Ups

Background Heart failure (HF) accounts for about 5% of all causes of urgent hospital admissions, and the overall mortality of HF patients within 1 year after hospitalization is 17–45%. Transthoracic impedance cardiography (ICG) is a safe, non-invasive diagnostic technique that helps to detect various parameters that define different cardiac functions. The aim of this study was to investigate the value of ICG parameters in patients hospitalized due to HF flare-ups. Material/Methods The study included 60 patients (24 women and 36 men) who were admitted to intensive care units because of an acute episode of HF without signs of myocardial infarction. The diagnosis of HF as the main reason for hospitalization was verified according to the universally accepted techniques. ICG data were compared to those obtained via other HF diagnostic techniques. Results A moderately strong relationship was found between the ejection fraction (EF) and the systolic time ratio (STR) r=−0.4 (p=0.002). Findings for STR and thoracic fluid content index (TFCI) differed after dividing the subjects into groups according to the EF (p<0.05). A moderately strong relationship was found between brain natriuretic peptide and TFCI r=0.425 (p=0.001), left cardiac work index (LCWI) r=−0.414 (p=0.001). Findings for TFCI, LCWI, and cardiac output differed after dividing the subjects into groups according to HF NYHA classes (p<0.05). Conclusions Transthoracic impedance cardiography parameters could be applied for the diagnostics and monitoring of HF, but further studies are required to evaluate the associations between ICG findings and HF.

Impedance plethysmography as an alternative method for the diagnosis of peripheral arterial disease.

BACKGROUND AND OBJECTIVE In the diagnosis of peripheral artery disease (PAD), the ankle-brachial index (ABI) is considered as the standard, and other noninvasive methods have received too little attention. Therefore, the aim of the study was to determine the diagnostic accuracy of impedance plethysmography in diagnosing PAD and to compare this method with other methods. MATERIALS AND METHODS A total of 66 patients with a mean age of 76.1±9.6 years who had been treated for various cardiovascular diseases at Kaunas Clinical Hospital during 2011-2012 were enrolled into the study. All the patients were screened for PAD. Impedance plethysmography was performed with a new-generation Niccomo™ device. The receiver operating characteristic analysis was employed to determine the diagnostic accuracy of 4 parameters of impedance plethysmography: crest time (CT), crest width (CW), pulse amplitude (Pampl), and alternating blood flow (ABF). RESULTS There were a significant correlation between the ABI and the CT (r=-0.699, P<0.001), between the ABI and the ABF (r=0.552; P<0.001), and between the ABI and the Pampl only among men (r=0.652; P<0001). No correlation was found between the ABI and the CW. Among all the parameters, the CT had the highest sensitivity and specificity (73.2% and 96.0%, respectively). Other parameters had the following sensitivities and specificities: ABF, 61.0% and 96.0%; and Pampl, 90.0% and 20.0%, respectively. CONCLUSIONS Impedance plethysmography, especially its parameter CT, is an alternative noninvasive method in diagnosing PAD and could be used for the screening of patients with PAD.

Serum BDNF and IL-6 response to high-volume mechanically demanding exercise

Introduction. The aim of this study was to follow circulating brain-derived neurotrophic factor (BDNF) and interleukin 6 (IL-6) levels in response to severe muscle-damaging exercise. Methods. Young healthy men (N=10) performed a bout of mechanically demanding stretch shortening cycle exercise consisting of 200 drop jumps. Voluntary and electrically induced knee extension torque, serum BDNF levels, and IL-6 levels were measured before and for up to 7 days after exercise. Results. Muscle force decreased by up to 40% and did not recover by 24 h after exercise. Serum BDNF was decreased 1 h and 24 h after exercise, while IL-6 increased immediately and 1 h after but recovered to baseline by 24 h after exercise. IL-6 and 100 Hz stimulation torque were correlated (r=–0.64, P<0.05) 24 h after exercise. Discussion. In response to acute severe muscle-damaging exercise, serum BDNF levels decrease, while IL-6 levels increase and are associated with peripheral fatigue. This article is protected by copyright. All rights reserved.Introduction: The aim of this study was to follow circulating brain‐derived neurotrophic factor (BDNF) and interleukin‐6 (IL‐6) levels in response to severe muscle‐damaging exercise. Methods: Young healthy men (N = 10) performed a bout of mechanically demanding stretch–shortening cycle exercise consisting of 200 drop jumps. Voluntary and electrically induced knee extension torque, serum BDNF levels, and IL‐6 levels were measured before and for up to 7 days after exercise. Results: Muscle force decreased by up to 40% and did not recover by 24 hours after exercise. Serum BDNF was decreased 1 hour and 24 hours after exercise, whereas IL‐6 increased immediately and 1 hour after but recovered to baseline by 24 hours after exercise. IL‐6 and 100‐Hz stimulation torque were correlated (r = −0.64, P < 0.05) 24 hours after exercise. Discussion: In response to acute, severe muscle‐damaging exercise, serum BDNF levels decrease, whereas IL‐6 levels increase and are associated with peripheral fatigue. Muscle Nerve 57: E46–E51, 2018

Serum brain‐derived neurotrophic factor and interleukin‐6 response to high‐volume mechanically demanding exercise

Introduction. The aim of this study was to follow circulating brain-derived neurotrophic factor (BDNF) and interleukin 6 (IL-6) levels in response to severe muscle-damaging exercise. Methods. Young healthy men (N=10) performed a bout of mechanically demanding stretch shortening cycle exercise consisting of 200 drop jumps. Voluntary and electrically induced knee extension torque, serum BDNF levels, and IL-6 levels were measured before and for up to 7 days after exercise. Results. Muscle force decreased by up to 40% and did not recover by 24 h after exercise. Serum BDNF was decreased 1 h and 24 h after exercise, while IL-6 increased immediately and 1 h after but recovered to baseline by 24 h after exercise. IL-6 and 100 Hz stimulation torque were correlated (r=–0.64, P<0.05) 24 h after exercise. Discussion. In response to acute severe muscle-damaging exercise, serum BDNF levels decrease, while IL-6 levels increase and are associated with peripheral fatigue. This article is protected by copyright. All rights reserved.Introduction: The aim of this study was to follow circulating brain‐derived neurotrophic factor (BDNF) and interleukin‐6 (IL‐6) levels in response to severe muscle‐damaging exercise. Methods: Young healthy men (N = 10) performed a bout of mechanically demanding stretch–shortening cycle exercise consisting of 200 drop jumps. Voluntary and electrically induced knee extension torque, serum BDNF levels, and IL‐6 levels were measured before and for up to 7 days after exercise. Results: Muscle force decreased by up to 40% and did not recover by 24 hours after exercise. Serum BDNF was decreased 1 hour and 24 hours after exercise, whereas IL‐6 increased immediately and 1 hour after but recovered to baseline by 24 hours after exercise. IL‐6 and 100‐Hz stimulation torque were correlated (r = −0.64, P < 0.05) 24 hours after exercise. Discussion: In response to acute, severe muscle‐damaging exercise, serum BDNF levels decrease, whereas IL‐6 levels increase and are associated with peripheral fatigue. Muscle Nerve 57: E46–E51, 2018

Impedanskardiografijos metodo galimybės diagnozuojant plaučių hipertenziją

Tyrimo tikslas. Istirti klinikinių, impedanskardiografijos, echokardioskopijos, krūtinės ląstos rentgenografijos duomenų sąsajas diagnozuojant plaucių hipertenziją sergantiesiems sirdies ir kraujagyslių arba kvėpavimo sistemų ligomis. Tyrimo medžiaga ir metodai. 181 pacientui (80 pacientų, sergancių sirdies ir kraujagyslių sistemos patologija, kai echokardioskopiskai nustatyta plaucių arterijos hipertenzija; 69 pacientams, sergantiems sirdies ir kraujagyslių sistemos patologija, kai echokardioskopiskai plaucių arterijos hipertenzijos nerasta; 19 pacientų, sergancių plaucių patologija, kai echokardioskopiskai plaucių arterijos hipertenzijos rasta; 13 pacientų, sergancių plaucių patologija, kai plaucių arterijos hipertenzijos nerasta) istirti buvo taikomi klinikiniai, dvimatės sirdies echoskopijos, impedanskardiografijos, kiti instrumentiniai tyrimai siekiant įvertinti, serganciųjų plaucių hipertenzija duomenų pokycius. Rezultatai. Impedanskardiografijos metodo jautrumas, diagnozuojant plaucių hipertenziją pagal vidutinį kraujo spaudimą plaucių arterijoje, 72 proc., specifiskumas – 90 proc., pagal sistolinį kraujo spaudimą plaucių arterijoje jautrumas – 96 proc., specifiskumas – 90 proc. Sudarytas matematinis dvejetainės logistinės regresijos modelis, pagal kurį 96,7 proc. tikslumu galima diagnozuoti plaucių hipertenziją. Svarbiausi impedanskardiografijos duomenys: sistolinis spaudimas plaucių arterijoje bei sistolinio laiko indeksas. Isvados. Impedanskardiografijos tyrimo metu nustatomi vidutinio ir sistolinio kraujo spaudimo plaucių arterijoje parametrai yra informatyvūs. Plaucių hipertenzijos diagnostikos algoritmuose galima būtų naudoti siuos požymius: priesirdžių virpėjimas, giliųjų venų trombozė, dusulys, cianozė, II tono akcentas plaucių arterijos vožtuvo isklausymo taske, sistolinis ūžesys ties triburiu vožtuvu, plaucių rentgenografijoje rastas padidėjes plaucių arterijos spindis ≥18 mm, padidėjes desiniojo skilvelio diametras, impedanskardiografijos metodu apskaiciuotas sistolinis spaudimas plaucių arterijoje bei sistolinio laiko indeksas.