On optimal use of radiation in cardiological procedures

In this thesis, the use of radiation in contemporary interventional cardiology (IC) has been investigated. The focus of the study is on patient doses in various minimally invasive procedures with higher doses. Patient exposure to radiation can be measured with Kerma area product (KAP) and its diagnostic reference levels (DRLs), maximum skin dose (MSD) and absorbed organ doses. In this thesis, all three doses are explored with accurate and repeatable methods and curiosity toward the causes behind the dose level variation. KAP results show that the highest patient doses in IC occur in transaortic valve implantations (TAVIs) and percutaneous coronary interventions (PCI) with significant variation between hospitals and countries. In TAVIs, this variation is partly due to the novelty of the procedure, but in PCIs, the need for difficulty levels in the DRLs is apparent. The machine learning methodology used in this thesis provides insight into how such difficulty levels can be determined and what kinds of features they should be comprised of. The MSD measurements performed with Gafchromic films show significantly higher dose levels in TAVIs than in other procedures and KAP and air kerma alert levels were proposed accordingly in Publication 3 of this thesis. The MSD levels show a high variance between hospitals and local DRLs were calculated for two of the participating hospitals. With the observed variation in respect to both KAP and air kerma, a good alternative to these alert levels are automatic skin dose estimations provided by the angiosystem manufacturers. In this work, two such algorithms were compared to the measured doses and the results were very promising. Heart organ dose was measured with radiophotoluminescence (RPL) dosimeters and an anthropomorphic phantom in both a computed tomography (CT) scan routinely performed before a TAVI procedure and in a typical TAVI procedure. The results show that a majority of the dose is caused by the CT scan and that the dose from the procedure is relatively low compared to other published results. In total, the thesis illustrates good investigative practices in radiation protection, their application to IC and results that benefit both contemporary cardiology and physicists working in the field

How random is your heart beat?

We measure the content of random uncorrelated noise in heart rate variability using a general method of noise level estimation using a coarse grained entropy. We show that usually - except for atrial fibrillation - the level of such noise is within 5 - 15% of the variance of the data and that the variability due to the linearly correlated processes is dominant in all cases analysed but atrial fibrillation. The nonlinear deterministic content of heart rate variability remains significant and may not be ignored.Comment: see http://urbanowicz.org.p

Guideline on carotid surgery for stroke prevention: updates from the Italian Society of Vascular and Endovascular Surgery. A trend towards personalized medicine

Background: This guideline (GL) on carotid surgery as updating of "Stroke: Italian guidelines for Prevention and Treatment" of the ISO-SPREAD Italian Stroke Organization-Group, has recently been published in the National Guideline System and shared with the Italian Society of Vascular and Endovascular Surgery (SICVE) and other Scientific Societies and Patient's Association. Methods: GRADE-SIGN version, AGREE quality of reporting checklist. Clinical questions formulated according to the PICO model. Recommendations developed based on clinical questions by a multidisciplinary experts' panel and patients' representatives. Systematic reviews performed for each PICO question. Considered judgements filled by assessing the evidence level, direction, and strength of the recommendations. Results: The panel provided indications and recommendations for appropriate, comprehensive, and individualized management of patients with carotid stenosis. Diagnostic and therapeutic processes of the best medical therapy, carotid endarterectomy (CEA), carotid stenting (CAS) according to the evidences and the judged opinions were included. Symptomatic carotid stenosis in elective and emergency, asymptomatic carotid stenosis, association with ischemic heart disease, preoperative diagnostics, types of anesthesia, monitoring in case of CEA, CEA techniques, comparison between CEA and CAS, post-surgical carotid restenosis, and medical therapy are the main topics, even with analysis of uncertainty areas for risk-benefit assessments in the individual patient (personalized medicine [PM]). Conclusions: This GL updates on the main recommendations for the most appropriate diagnostic and medical-surgical management of patients with atherosclerotic carotid artery stenosis to prevent ischemic stroke. This GL also provides useful elements for the application of PM in good clinical practice

The value of comorbidities and illness severity scores as prognostic tools for early outcome estimation in patients with aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe cerebrovascular disease not only causing brain injury but also frequently inducing a significant systemic reaction affecting multiple organ systems. In addition to hemorrhage severity, comorbidities and acute extracerebral organ dysfunction may impact the prognosis after aSAH as well. The study objective was to assess the value of illness severity scores for early outcome estimation after aSAH. A retrospective analysis of consecutive aSAH patients treated from 2012 to 2020 was performed. Comorbidities were evaluated applying the Charlson comorbidity index (CCI) and the American Society of Anesthesiologists (ASA) classification. Organ dysfunction was assessed by calculating the simplified acute physiology score (SAPS II) 24 h after admission. Modified Rankin scale (mRS) at 3 months was documented. The outcome discrimination power was evaluated. A total of 315 patients were analyzed. Significant comorbidities (CCI > 3) and physical performance impairment (ASA > 3) were found in 15% and 12% of all patients, respectively. The best outcome discrimination power showed SAPS II (AUC 0.76), whereas ASA (AUC 0.65) and CCI (AUC 0.64) exhibited lower discrimination power. A SAPS II cutoff of 40 could reliably discriminate patients with good (mRS ≤ 3) from those with poor outcome (p < 0.0001). Calculation of SAPS II allowed a comprehensive depiction of acute organ dysfunctions and facilitated a reliable early prognosis estimation in our study. In direct comparison to CCI and ASA, SAPS II demonstrated the highest discrimination power and deserves a consideration as a prognostic tool after aSAH

Impedance cardiography: A valuable method of evaluating haemodynamic parameters

This year marks 40 years since the technique was designed of measuring and monitoring the basic haemodynamic parameters in humans by means of impedance cardiography (ICG), also known as "impedance plethysmography of the chest", "electrical bioimpedance of the chest" or "reocardiography". The method makes it possible to denote stroke volume and cardiac output. It also enables the factors to be assessed that influence the following: preload (measurement of thoracic fluid content), afterload (measurement of systemic vascular resistance), the systemic vascular resistance index, contractibility (measurement of the acceleration index), the velocity index, the pre-ejection period, left ventricular ejection time, systolic time ratio and heart rate. Advances in hardware and software, including digital signal tooling and new algorithms, have certainly improved the quality of the results obtained. The accuracy and repeatability of the results have been confirmed in comparative studies with results obtained through invasive methods and echocardiography. Not only are haemodynamic changes monitored by means of ICG in intensive care units, in operating theatres and at haemodialysis stations, but repeated measurements also provide haemodynamic information during the treatment of patients with hypertension and heart failure and pregnant women with cardiological problems and gestosis. A single ICG investigation makes a great contribution to the basic information available about the circulatory system, which is helpful in the initial evaluation of patients in a severe general condition (for example in the admission room), and also makes it possible to make a swift diagnosis of the cause of complaints such as dyspnoea and hypotonia. A particular application of ICG is the assessment of haemodynamic parameters during the programming of atrioventricular and CRT pacemakers. Besides these uses, ICG is a valuable investigative tool. It is defect-free and does not have pulmonary artery pressure monitoring limitations. Moreover, it is not as time-consuming as echocardiography and the examination can be performed by trained technicians or nurses. (Cardiol J 2007; 14: 115-126

Синдром обструктивного апноэ сна и фибрилляция предсердий: двунаправленная связь

Highlights. The data regarding the relationship between obstructive sleep apnea syndrome and atrial fibrillation were analyzed.Abstract. The review article presents current data on the relationship between obstructive sleep apnea syndrome and atrial fibrillation. The spread of these pathological processes increases with age and is associated with a significant risk of cardiovascular complications. In this regard, this review seems to be quite relevant. Possible pathophysiological mechanisms influencing the relationship between obstructive sleep apnea syndrome and atrial fibrillation are discussed. The role of CPAP therapy - Continuous Positive Airway Pressure in the prevention and treatment of atrial fibrillation is highlighted.Основные положения. Проанализированы и приведены данные о взаимосвязи синдрома обструктивного апноэ сна и фибрилляции предсердий.Резюме. В обзорной статье представлены современные данные о взаимосвязи синдрома обструктивного апноэ сна и фибрилляции предсердий. Распространение этих патологических процессов увеличивается с возрастом больных и сопряжено со значительным риском сердечно-сосудистых осложнений, что определяет актуальность представленной работы. Проанализированы возможные патофизиологические механизмы, влияющие на взаимосвязь синдрома обструктивного апноэ сна и фибрилляции предсердий. Освещена роль СИПАП-терапии (от англ. Continuous Positive Airway Pressure, СРАР) в профилактике и лечении фибрилляции предсердий

Use of transthoracic Doppler echocardiography combined with clinical and electrocardiographic data to predict acute pulmonary embolism

Transthoracic echocardiography and continuous wave Doppler were prospectively performed in 132 out-patients with suspicion of pulmonary embolism, and who had no previous history of severe cardiac or pulmonary disease. Bedside echocardiography determined diagnosis other than pulmonary embolism in 55 patients. Further study was completed in 70 patients; pulmonary embolism was found in 31 and excluded in 39. Significant differences were found as regards right ventricular diameter (27 ± 8 vs 22 ± 5 mm, -P&lt;0001), left ventricular diameter (41 ±9 vs 49 ± 7 mm, /&gt;&lt;0001), right over left ventricular diameter ratio (0-67 ± 0-23 vs 0-43 ± 015, P&lt;00001), tricuspid regurgitant flow peak velocity (2-9 ±0-4 vs 2-4 ± 0-7 m . s &quot; &apos;, / &gt; &lt;00001), and abnormal septum motion (12 vs 4, /&gt;&lt;001). Multivariate analysis of echocardiographic data included a tricuspid regurgitant flow peak velocity greater than 25 m . s &apos; and a right over left ventricular diameter ratio greater than 0-5 in a logistic model (sensitivity 93%, specificity 81%). The combination of echocardiographic and non-echocardiographic data included the two previous echocardiographic variables, together with signs of deep vein thrombosis, a deep S wave in lead Dl, and a Q wave in lead D3 on the electrocardiogram in a logistic model (sensitivity 96%, specificity 83%). It can be concluded that emergency echocardiography, alone or combined with clinical examination and electrocardiogram, satisfactorily predicts acute pulmonary embolism. (Eur Heart J 1996; 17: 779-786