Bedömningen av höger kammares systoliska funktion kan med fördel göras med ekokardiografi, bl.a. med tekniker som tvådimensionell ekokardiografi, motion-mode (M-mode) och Tissue Doppler Imaging (TDI). Mätvärden som kan fås ut av dessa tekniker är Tricuspid Annular Plane Systolic Excursion (TAPSE) och s`. TAPSE beskriver annulus tricuspidalis longitudinella rörlighet. s´ beskriver den maximala systoliska hastigheten i annulus tricuspidalis. Syftet med examensarbetet var att undersöka sambandet mellan TAPSE och s´ vid högerkammarfunktionsbestämning. Studien är en retrospektiv tvärsnittsstudie och består av 99 deltagare i åldrarna 18–90 år. Både friska och hjärt-och kärlsjuka deltagare inkluderades, men inte patienter med förmaksflimmer eller individer som var yngre än 18 år. Deltagarna undersöktes med transthorakal ekokardiografi (TTE) vid Länssjukhuset Ryhov i Jönköping, vid undersökningen mättes TAPSE och s´. Det var samma biomedicinska analytiker (BMA) som utförde undersökningarna. McNemars test utfördes och ett Kappa-värde räknades ut. Resultatet visade signifikant skillnad och Kappa-värdet var lågt vilket talar för dåligt samband mellan de båda variablerna. Utfallet i studien visar att fler deltagare klassas med normal högerkammarfunktion mätt med TAPSE, medan samma individer klassas med högerkammardysfunktion mätt med s´. Orsaken till det dåliga sambandet mellan parametrarna är okänt och bör studeras vidare i kommande studier. / The assessment of right ventricular systolic function is done by echocardiography, with techniques as twodimensional echocardiography, motion-mode (M-mode) and Tissue Doppler Imaging (TDI). Measurements ​​obtained from these techniques are Tricuspid Annular Plane Systolic Excursion (TAPSE) and s`. TAPSE describes the longitudinal movement of annulus tricuspidalis. s´ describes annulus tricuspidalis maximal systolic velocity. The purpose of this essay was to explore the relationship between TAPSE and s´. The study consists of 99 participants between the ages of 18 and 90. The population was consisted of individuals with or without cardiovascular disease, but not individuals with atrial fibrillation. Participants were investigated with transthorakal echocardiography (TTE) at Länssjukhuset Ryhov in Jönköping. At the examination both TAPSE and s´ was measured. McNemar's test was performed and a Kappa value was calculated. The result showed a significant difference and the Kappa value was low which indicates a low relationship between the variables. The outcome of the study shows that several participants are classified with normal right ventricular function measured with TAPSE, but the same individuals are classified with right ventricular dysfunction measured by s'. The reason for the poor relationship between the parameters is unknown and should be studied further in future studies.

There is a large need for accurate methods detecting cardiovascular diseases, since they are one of the leading causes of mortality in the world, accounting for 29.3% of all deaths. Due to the complexity of the cardiovascular system, it is very challenging to develop methods for quantification of its function in order to diagnose, prevent and treat cardiovascular diseases. Ultrasound is a technique allowing for inexpensive, noninvasive imaging, but requires an experienced echocardiographer. Nowadays, methods like Tissue Doppler imaging (TDI) and Speckle tracking imaging (STI), measuring motion and deformation in the myocardium and the vessel walls, are getting more common in routine clinical practice, but without a proper visualization of the data provided by these methods, they are time-consuming and difficult to interpret. Thus, the general aim of this thesis was to develop novel ultrasound-based methods for accurate quantification and easily interpretable visualization of cardiovascular function. Five methods based on TDI and STI were developed in the present studies. The first study comprised development of a method for generation of bull’s-eye plots providing a color-coded two-dimensional visualization of myocardial longitudinal velocities. The second study proposed the state diagram of the heart as a new circular visualization tool for cardiac mechanics, including segmental color-coding of cardiac time intervals. The third study included development of a method describing the rotation pattern of the left ventricle by calculating rotation axes at different levels of the left ventricle throughout the cardiac cycle. In the fourth study, deformation data from the artery wall were tested as input to wave intensity analysis providing information of the ventricular – arterial interaction. The fifth study included an in-silico feasibility study to test the assessment of both radial and longitudinal strain in a kinematic model of the carotid artery. The studies showed promising results indicating that the methods have potential for the detection of different cardiovascular diseases and are feasible for use in the clinical setting. However, further development of the methods and both quantitative comparison of user dependency, accuracy and ease of use with other established methods evaluating cardiovascular function, as well as additional testing of the clinical potential in larger study populations, are needed. / QC 20100727

Pain and disorders of the human skeletal muscles are one of the most common reasons for medical consultations in the western countries today and there is a great need to improve both the understanding and treatment of several different muscular conditions. Techniques describing the muscle function in vivo are often limited by either their invasiveness or lack of spatial resolution. Electromyography (EMG) is the most common approach to assess the skeletal muscle function in vivo, providing information on the neurological input. However, the spatial resolution is in general limited and there are difficulties reaching deep musculature without using invasive needles. Moreover, it does not provide any information about muscle structure or mechanical aspects. Quantitative ultrasound techniques have gained interest in the area of skeletal muscles and enables non-invasive and in-vivo insight to the intramuscular activity, through the mechanical response of the activation. However, these techniques are developed and evaluated for cardiovascular applications and there are important considerations to be made when applying these methods in the musculoskeletal field.  This thesis is based on the work from four papers with the main focus to investigate and describe some of these considerations in combination with the development of processing and analyzing methods that can be used to describe the physiological characteristics of active muscle tissue. In the first paper the accuracy of the Doppler based technique Tissue Velocity Imaging (TVI) was evaluated in a phantom study for very low tissue velocities and the effect of the pulse repetition frequency was considered. The second paper presents a biomechanical model to describe the TVI strain’s dependency on the muscle fiber pennation angle. In the third and fourth papers the intramuscular activity pattern was assessed through the regional tissue deformation by motion mode (M-mode) strain imaging. The activity patterns were analyzed during force regulation and for the effects of fatigue. The work of this thesis show promising results for the application of these methods on skeletal muscles and indicate high clinical potential where quantitative ultrasound may be a valuable tool to reach a more multifaceted and comprehensive insight in the musculoskeletal function. However, the methodological considerations are highly important for the optimized application and further evaluation and development of analyzing strategies are needed. / <p>QC 20130516</p>

Vid flertalet hjärtsjukdomar kan det förekomma störningar i den diastoliska funktionen, detta tillstånd benämns diastolisk dysfunktion. Detta innebär att fyllnadstrycken i vänsterkammare ökar på grund av nedsatt eftergivlighet i kammaren. Bedömning av diastolisk funktion, hos patienter som utvecklat förmaksflimmer, är en utmaning inom ekokardiografi. Detta beror på att förmaksflimmer innebär utebliven förmakskontraktion, oregelbunden längd av hjärtcykeln och förmaksdilatation, vilket försvårar bedömningen. Syftet med studien var att med ekokardiografi studera diastoliska parametrar hos patienter med förmaksflimmer för att studera om dessa kan användas vid bedömning av den diastoliska vänsterkammarfunktionen hos denna patientgrupp. I studien inkluderades 37 deltagare med förmaksflimmer som var remitterade för en ekokardiografisk undersökning med olika frågeställningar. Pulsad doppler teknik och vävnads doppler teknik användes för att registrera följande diastoliska parametrar: förmaksvolym, mitralisinflöde (E-vågshastigheten) och myokardiets diastoliska hastigheter (e´). Utöver dessa uppskattades även ejektionsfraktion, hjärtfrekvens, hypertrofi och trycket i lilla kretsloppet, som togs med vid bedömningen. Mann-Whitneys test visade att det förelåg ett starkt statistiskt samband mellan fyllnadstrycket (E/e´) och E-vågen, e ´samt förmaksvolym (p = <0,05). Signifikant resultat erhölls även för sambandet mellan PA-tryck och fyllnadstryck (p = 0,014) genom ett chitvå-test. Vidare gav multipel linjär regression utslag på E-vågen och e´. Analysen visade att det förelåg en hög förklaringsgrad för E-vågen (p = <0,001) och e´ (p = 0,008). Sammanfattningsvis visade resultaten att ekokardiografi kan användas för diagnostik av förmaksflimmerpatienter avseende fyllnadstryck där förmaksvolym, E-vågshastigheten och e´ anses vara bästa parametrarna. / In the majority of heart diseases disturbances in the diastolic function may occur, this condition is called diastolic dysfunction. This means that the left ventricular filling pressure increases due to reduced compliance in the chamber. The assessment of diastolic function in patients who have developed atrial fibrillation (AF), is a challenge in echocardiography. This is a result of AF which involves absence of atrial contraction, irregular length of the cardiac cycle and left atrium dilatation that complicates the assessment. The aim of this study was to observe the diastolic echocardiographic parameters in patients with AF to examine if these can be used in the assessment of diastolic left ventricular function in this population. The study included 37 participants with AF who were remitted for an echocardiographic examination due to various concerns. Pulsed Doppler technique and tissue Doppler technique was used to record the following diastolic parameters: atrial volume, mitral inflow velocity (E) and the myocardial diastolic velocity (e'). Ejection fraction, heart-rate, hypertrophy and pulmonary artery pressure were also estimated and included in the assessment. Mann-Whitneys test showed that there was a strong statistical correlation between the filling pressure (E/e') and E, e' and atrial volume (p = <0.05). Significant results were also obtained for the relation between pulmonary artery pressure and the filling pressure (p = 0.014) by a chi-square test. A multiple linear regression showed association between E and e'. The analysis showed that there was a significant value of coefficient of determination for E (p = <0.001) and e' (p = 0.008). In conclusion, the results showed that echocardiography can be used for diagnosis of AF patients regarding filling pressures, where atrial volume, E velocity and e' are considered to be the best parameters.