Dissertation of Pulmonary Hypertension (Dissertation Sample)

Dissertation draftAbbreviations CMRCardiovascular Magnetic Resonance imaging CTEPHChronic thromboembolic pulmonary hypertension CTPACT pulmonary angiography ECEndothelial cell ECGElectrocardiogram FT Feature Tracking FT CMR Feature Tracking Cardiac Magnetic Resonance HRHazard ratios HRCThigh-resolution CT LA EDA SLA End-Diastolic Area Strain LA ENDOGCS SLA Endocardial Global Circumferential Strain LA ENDOGLS S LA Endocardial Global Longitudinal Strain LA ESA S LA End-Systolic Area Strain LA FAC S LA Fractional Area Change Strain LA GRS S LA Global Radial Strain LV EDA S LV End-Diastolic Area Strain LV ENDOGCS SLV Endocardial Global Circumferential Strain LV ENDOGLS S LV Endocardial Global Longitudinal Strain LV ESA S LV End-Systolic Area Strain LV GRS S LV Global Radial Strain LV SD-LS-PeakLV SD-Longitudinal Strain-Peak LVEDVI LV end diastolic volume index LVEF LV ejection fraction LVESVI LV end systolic volume index LVSVI LV stroke volume index mPAP mean pulmonary artery pressure MRIMagnetic Resonance Imaging PAPulmonary artery PAHPulmonary arterial hypertension PCWPulmonary capillary wedge PFTPulmonary function test PHPulmonary hypertension PH-LHDPulmonary hypertension due to left heart disease PH-LungPulmonary hypertension due to lung disease or hypoxia PVR Pulmonary vascular resistance RA EDA S RA End-Diastolic Area Strain RA ENDOGCS S RA Endocardial Global Circumferential Strain RA ENDOGLS S RA Endocardial Global Longitudinal Strain RA ESA S RA End-Systolic Area Strain RA FAC S RA Fractional Area Change Strain RA GRS S RA Global Radial Strain RHCRight heart catheterisation RVRight ventricular RV EDA S RV End-Diastolic Area Strain RV ENDOGLS S RV Endocardial Global Longitudinal Strain RV ESA S RV End-Systolic Area Strain RV FAC S RV Fractional Area Change Strain RVEDV RV end-diastolic volume RVEDVI RV end diastolic volume index RVEF RV ejection fraction RVEF RV ejection fraction RVESV RV end-systolic volume RVESVI RV end systolic volume index RVFACRV fractional area change RVmassI RV mass index RVSV Right ventricular stroke volume RVSVI RV stroke volume index SOBShortness of breath SSFP Steady State Free Precession STE Speckle Tracking Echocardiography SvO2Mixed venous oxygen saturation TTETransthoracic echocardiogram WHOWorld Health Organization Chapter 1: Introduction 1.1: Pulmonary Hypertension Pulmonary hypertension (PH) is a haemodynamic state of elevated blood pressure in the pulmonary arteries. According to (Hurdman et al., 2012), PH is an condition affecting the young and the old, dominated by the females. Elevated pressure in the pulmonary artery is measured by right heart catheterisation (RHC).  The constant mean pulmonary arterial pressure (mPAP) in a well person equates to 14 ± 3 mmHg (Kovacs et al., 2009. PH is defined as mPAP above or equivalent to 25 mmHg while resting. (Humbert et al., 2006a). Elevated pulmonary arterial pressure placed high afterload on the right ventricular (RV), causing a dysfunction in the RV and ultimately failure to survive.  High afterload on RV leads to a drop in the cardiac output. Symptoms include shortness of breath (SOB), and a decrease in exercise ability (Kiely et al., 2013). Conforming to (Galie et al., 2009), PH disease have been divided into five main groups by the World Health Organization (WHO). One of the widespread conditions of PH is pulmonary arterial hypertension (PAH). Obstruction of small arteries in the lung causes PAH for various reasons listed in Table 1.1. Main groups of PH 1. Pulmonary arterial hypertension (PAH) * Idiopathic * Heritable * Drugs and toxins induced * Associated with; connective tissue disease, HIV infection, portal hypertension, congenital heart disease, schistosomiasis or chronic heamolytic anaemia * Persistent pulmonary anaemia 2. Pulmonary hypertension due to left heart disease (PH-LHD) 3. Pulmonary hypertension due to lung disease or hypoxia (PH-Lung) 4. Chronic thromboembolic pulmonary hypertension (CTEPH) 5. Other uncommon causes of PH Table 1.1: Shows the diagnostic grouping of pulmonary hypertension. Adapted from (Galie et al., 2009). For the 
previous couple of decades substantial development of PAH therapy, however PAH remains a health condition lessening the lifespan. Research 
of severity of disease and approximating lifespan is a vital section in assessing patient. It helps in choosing of treatment approach, skilled transplant, and patients counseling (Galie et al., 2015). Myocardial strain gives data for several of heart related ailments thus assisting medical officers to accurately make assessments to their patients (Shah and Solomon, 2012). Many approaches have been advanced in the CMR field determine myocardial strain. The most practical a semi-automated approach being FT does not need extra succession and is angle sovereign. 1.1.1: Pathogenesis and classification of PH Rosenberg and Rabinovitch (1988) research have indicated that the distal vessel remodeling of the lungs is initially caused by endothelial cell (EC) damage and change of the proximal pulmonary artery (PA). This results in higher intra-arterial pressures of PA blood flow after it altered to be non-compliant and stiffened. The key of distal vessel thickening is < 500 micrometers that leads to increased resistance in the lungs is the primary aetiology of group 1 PAH. Symptoms and signs Shortness of breath is a very dominant symptom of PAH. Other symptoms and signs of PAH are irregular heartbeat, tiredness, fainting, chest pain, and swelling of the leg. The WHO grouped PH patients according to their symptomatic severity.  The different PH WHO classes are shown in Table 1.2 Functional Class Clinical Picture I Patients with PH but no SOB, fatigue, chest pain, or fainting during regular physical activity. II Patients with PH and have symptoms such as SOB, fatigue, chest pain, or fainting present during regular physical activity. However, symptoms will disappear while resting. III Patients with PH and have symptoms such as severe SOB, fatigue, chest pain, or fainting present with less than regular physical activity. Notably, symptoms may disappear while resting. IV Patient with PH and manifest signs of right heart failure. Symptoms present with any physical activity. Importantly, symptoms may appear during rest. Table 1.2: Shows the Functional classification of PH modified after the New York Heart Association functional classification according to the WHO. Adapted from ADDIN EN.CITE <EndNote><Cite><Author>Galie</Author><Year>2009</Year><IDText>Guidelines for the diagnosis and treatment of pulmonary hypertension</IDText><DisplayText>(Galie et al., 2009b)</DisplayText><record><dates><pub-dates><date>Oct</date></pub-dates><year>2009</year></dates><urls><related-urls><url>&lt;Go to ISI&gt;://WOS:000270985300023</url></related-urls></urls><isbn>0195-668X</isbn><titles><title>Guidelines for the diagnosis and treatment of pulmonary hypertension</title><secondary-title>European Heart Journal</secondary-title></titles><pages>2493-2537</pages><number>20</number><contributors><authors><author>Galie, N.</author><author>Hoeper, M. M.</author><author>Humbert, M.</author><author>Torbicki, A.</author><author>Vachiery, J. L.</author><author>Barbera, J. A.</author><author>Beghetti, M.</author><author>Corris, P.</author><author>Gaine, S.</author><author>Gibbs, J. S.</author><author>Gomez-Sanchez, M. A.</author><author>Jondeau, G.</author><author>Klepetko, W.</author><author>Opitz, C.</author><author>Peacock, A.</author><author>Rubin, L.</author><author>Zellweger, M.</author><author>Simonneau, G.</author><author>Ishlt,</author></authors></contributors><added-date format="utc">1515574392</added-date><ref-type name="Journal Article">17</ref-type><rec-number>36</rec-number><last-updated-date format="utc">1515574392</last-updated-date><accession-num>WOS:000270985300023</accession-num><electronic-resource-num>10.1093/eurheartj/ehp297</electronic-resource-num><volume>30</volume></record></Cite></EndNote>(Galie et al., 2009). 1.1.2: Prevalence and Incidence There is a scarcity of information concerning prevalence and incidence of PH as well as, more precisely, PAH. Suri et al. (2013) pointed out that the PAH predominance was realised in one echocardiographic research in Australian averaged to 6.2% of PH patients, and in a different but bigger Australian research to 4.2% of PH patients (Strange et al., 2012). There are about 1.1 incident circumstances of PAH in a million persons annually, having overall of 6.6 instances in a million people approximated in UK PAH prevalence in the (Ling et al., 2012). 1.1.3: Diagnostic Modalities First assessment includes history, and examination to detect signs and symptoms indicative of PH or those conditions commonly related such as lung disease, left heart disease or connective tissue disease. Typical first stage investigations include, X-ray of the chest, pulmonary function test (PFT), transthoracic echocardiogram (TTE), Electrocardiogram (ECG) and CT pulmonary angiography (CTPA), high-resolution CT (HRCT), and nuclear scans are included in standard methodologies of diagnosing and ought to be practiced (McGoon et al., 2004). RHC is the affirming test for the diagnosis of PH and to examine the haemodynamics of...