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Intimal Pulmonary Artery Sarcoma Presenting as Severe Dyspnea and Right Heart InsufficiencyHalank, Michael, Jakob, Christiane, Kolditz, Martin, Höffken, Gerd, Kappert, Utz, Ehninger, Gerhard, Weise, Matthias 24 February 2014 (has links) (PDF)
Background: Pulmonary artery sarcoma is a rare tumor with a poor prognosis. Case Report: We report the case of a 64-year-old man with an intimal pulmonary artery sarcoma presenting with severe high oxygen flow-demanding dyspnea and weight loss of 12 kg in the last 6 months. On echocardiography, right heart insufficiency, markedly elevated right ventricular pressure, a pressure gradient along the right outflow tract, and a tumor mass adherent to the wall of the truncus pulmonalis were detected. The tentative diagnosis by echocardiographic findings was pulmonary artery sarcoma. Computed tomography of the thorax and 18-fluorodeoxyglucose positron emission tomography showed an advanced local tumor manifestation. Surgical resection of the tumor to improve hemodynamics confirmed the diagnosis. Conclusions: Pulmonary artery sarcoma should be considered as a rare differential diagnosis in patients with dyspnea due to right heart failure, particular in the case of additional weight loss, and echocardiographic examination is a useful first diagnostic approach in establishing the diagnosis. / Hintergrund: Das Pulmonalarteriensarkom ist eine seltene Erkrankung mit einer schlechten Prognose. Fallbericht: Wir berichten über einen 64-jährigen Mann mit einem intimalen Pulmonalarteriensarkom, der sich mit starker Luftnot trotz hoher Sauerstoffsubstitution und einem Gewichtsverlust von 12 kg in den letzten 6 Monaten vorstellte. Echokardiographisch fielen eine Rechtsherzinsuffizienz, ein deutlich erhöhter rechtsventrikulärer Druck, ein Druckgradient über dem rechten Ausflusstrakt und eine Tumormasse im Bereich des Trunkus pulmonalis mit Kontakt zur Gefäßwand auf. Die mittels Echokardiographie erhobene Verdachtsdiagnose lautete Pulmonalarteriensarkom. Die Computertomographie des Thorax und die 18-Flur-Desoxyglukose-Positron-Emissionstomographie erbrachten den Befund eines lokal fortgeschrittenen Tumors. Die chirurgische Resektion des Tumors, die zur Verbesserung der Hämodynamik durchgeführt wurde, bestätigte die Diagnose. Schlussfolgerungen: Das Pulmonalarteriensarkom sollte differenzialdiagnostisch als eine seltene Ursache der Luftnot im Rahmen einer Rechtsherzinsuffizienz, insbesondere bei zusätzlichem Gewichtsverlust, in Erwägung gezogen werden. Die Echokardiographie stellt eine wertvolle initiale Untersuchungsmethode bei der Diagnosestellung dar. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Voraussetzungen für die Einführung neuer bildgebender Verfahren in bestehende Strukturen / Requirements for the introduction of new imaging technologies to existing strucuresSanner, Felix 23 April 2014 (has links)
No description available.
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The clinical value of total isovolumic timeBajraktari, Gani January 2014 (has links)
The objective of this thesis is to evaluate the use of Doppler echocardiography markers ofglobal dyssynchrony [total isovolumic time (t-IVT)] in the following 6 studies: 1) Its prognostic role in predicting cardiac events in patients undergoing CABG surgery,compared with conventional global systolic and diastolic measurements. 2) Its additional value in predicting six minute walk test (6-MWT) in patients with leftventricular (LV) ejection fraction (EF) <45%. 3) Its prognostic value in comparison with other clinical, biochemical and echocardiographicvariables in patients with chronic systolic heart failure (HF). 4) The relationship between 6-MWT and cardiac function measurements in a consecutivegroup of patients, irrespective of EF and to identify predictors of exercise capacity. 5) To investigate the effect of age on LV t-IVT and Tei index compared with conventionalsystolic and diastolic parameters. 6) To assess potential additional value of markers of global LV dyssynchrony in predictingcardiac resynchronization therapy (CRT) response in HF patients. Study I Methods: This study included 74 patients before routine CABG who were followed up for18±12 months. Results: At follow-up, 29 patients were hospitalized for a cardiac event or died. LV-ESD wasgreater (P=0.003), fractional shortening (FS) lower (p<0.001), E:A ratio and Tei index higher(all P<0.001), and t-IVT longer (P<0.001) in patients with events. Low FS [0.66 (0.50–0.87),P<0.001], high E:A ratio [l4.13 (1.17–14.60), P=0.028], large LV-ESD [0.19 (0.05–0.84),P=0.029], and long t-IVT [1.37 (1.02–1.84), P=0.035] predicted events and deaths. Conclusion: Despite satisfactory surgical revascularization, long t-IVT and systolicdysfunction suggest persistent ventricular dyssynchrony that contributes to post-CABGcardiac events. Study II Methods: We studied 77 patients (60±12 year, and 33.3% females) with stable HF using 6-MWT.iii Results: E’ wave (r=0.61, p<0.001), E/e’ ratio (r=-0.49, p<0.001), t-IVT (r=-0.44, p<0.001),Tei index (r=-0.43, p<0.001) and NYHA class (r=-0.53, p<0.001) had the highest correlationwith the 6-MWT distance. In multivariate analysis, only E/e’ ratio [0.800 (0.665-0.961),p=0.017], and t-IVT [0.769 (0.619-0.955), p=0.018] independently predicted poor 6-MWTperformance (<300m). Conclusions: In HF, the higher the filling pressures and the more dyssynchronous the LV, thepoorer is the patient’s exercise capacity. Study III Methods: We studied 107 systolic HF patients; age 68±12 year, 25% females and measuredplasma NT-pro-BNP. Results: Over a follow-up period of 3718 months, t-IVT ≥12.3 sec/min, mean E/Em ratio≥10, log NT-pro-BNP levels ≥2.47 pg/ml and LV EF ≤32.5% predicted clinical events. Theaddition of t-IVT and NT-pro-BNP to conventional clinical and echocardiographic variablessignificantly improved the χ2 for the prediction of outcome from 33.1 to 38.0, (p<0.001). Conclusions: Prolonged t-IVT adds to the prognostic stratification of patients with systolicHF. Study IV Methods: We studied 147 HF patients (61±11 year, 50.3% male) with 6-MWT.Results: The 6-MWT correlated with t-IVT (r=-0.49, p<0.001) and Tei index (r=-0.43,p<0.001) but not with any of the other clinical or echocardiographic parameters. Group Ipatients (<300m) had lower Hb (p=0.02), lower EF (p=0.003), larger left atrium (p=0.02),thicker septum (p=0.02), lower A wave (p=0.01) and lateral wall a’ (p=0.047), longerisovolumic relaxation time (r=0.003) and longer t-IVT (p= 0.03), compared with Group II(>300m). Only t-IVT ratio [1.257 (1.071-1.476), p=0.005], LV EF [0.947 (0.903-0.993),p=0.02], and E/A ratio [0.553 (0.315-0.972), p=0.04] independently predicted poor 6-MWTperformance. Conclusion: In HF, the limited 6-MWT is related mostly to severity of global LVdyssynchrony, more than EF or raised filling pressures. Study V Methods: We studied 47 healthy individuals (age 62±12 year, 24 female), arbitrarilyclassified into: M (middle age), S (seniors), and E (elderly). Results: Age strongly correlated with t-IVT (r=0.8, p<0.001) and with Tei index (r=0.7,p<0.001), E/A ratio (r=-0.6, p<0.001), but not with global or segmental systolic function measurements or QRS duration. The normal upper limit of the t-IVT (95% CI) for the three groups was 8.3 s/min, 10.5 s/min and 14.5 s/min, respectively, being shorter in the S compared with the E group (p=0.001). T-IVT correlated with A wave (r=0.66, p<0.001), E/Aratio (r=-0.56, p<0.001), septal e’ (r=-0.49, p=0.001) and septal a’ (r=0.4, p=0.006), but notwith QRS. Conclusions: In normals, age is associated with exaggerated LV global dyssynchrony anddiastolic function disturbances, but systolic function remains unaffected. Study VI Methods: We studied 103 HF patients (67±12 year, 82.5% male) recruited for CRTtreatment. Results: Prolonged t-IVT [0.878 (0.802-0.962), p=0.005], long QRS duration [0.978 (0.960-0.996), p=0.02] and high tricuspid regurgitation pressure drop (TRPD) [1.047 (1.001-1.096),p=0.046] independently predicted response to CRT. A t-IVT ≥11.6 s/min was 67% sensitiveand 62% specific (AUC 0.69, p=0.001) in predicting CRT response. Respective values for aQRS ≥ 151ms were 66% and 62% (AUC 0.65, p=0.01). Combining the two variables had asensitivity of 67% but higher specificity of 88% in predicting CRT response. In atrialfibrillation (AF) patients, only prolonged t-IVT ≥11 s/min [0.690 (0.509-0.937), p=0.03]independently predicted CRT response with a sensitivity of 69% and specificity of 79% (AUC0.78, p=0.015). Conclusion: Combining prolonged t-IVT and broad QRS had higher specificity in predictingresponse to CRT, with the former the sole predictor of response in AF patients.
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Cardiopulmonary involvement in Puumala hantavirus infectionRasmuson, Johan January 2015 (has links)
Puumala hantavirus (PUUV) causes hemorrhagic fever with renal syndrome in Europe. After inhalation of virus shed by bank voles, the virus systemically targets the vascular endothelium leading to vascular dysfunction and leakage. Many patients with PUUV infection experience cardiopulmonary manifestations but the underlying mechanisms have not been determined. The aims of the studies presented were to describe cardiopulmonary manifestations, investigate pathogenetic mechanisms including presence of virus in the lungs and the local immune response in PUUV infection. The results showed cardiopulmonary involvement of varying severity in almost all studied patients. High-resolution computed tomography frequently revealed vascular leakage into the lungs or pleural cavities. Pulmonary function tests generally showed reduced gas diffusing capacity, evidenced in patients as dyspnea, poor oxygenation and frequent need of oxygen treatment. Among patients who were not fully recovered at 3 months follow-up, remaining decreased gas diffusing capacity was highly common. Echocardiography revealed mainly right heart dysfunction which was related to manifestations within the lungs, in terms of increased estimated pulmonary vascular resistance, mild to moderate pulmonary hypertension, and reduced right ventricular systolic function in patients with more pronounced lung involvement, as indicated by need of oxygen treatment. Analyses on bronchoalveolar lavage (BAL) and bronchial biopsies revealed a highly activated cytotoxic T cell (CTL) response in the lungs. The CTL response was not balanced by the expansion of regulatory T cells and high numbers of CTLs were associated with more severe disease. PUUV RNA was detected in almost all patients’ BAL samples and the viral load was inversely correlated to the number of CTLs. Three patients presenting with severe and fatal cardiopulmonary distress were also described. Autopsies revealed PUUV protein in vascular endothelium in all investigated organs, including the heart and lungs, along with a massive CTL response mainly in the lungs. In conclusion, cardiopulmonary involvement of varying severity was present in almost all patients with PUUV infection. Cytotoxic immune responses could contribute to disease development but also help in clearing the infection. Long lasting fatigue after hantavirus infection may be explained by remaining manifestations within the lungs.
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Left Ventricular Diastolic (Dys)Function in SepsisDavid Sturgess Unknown Date (has links)
BACKGROUND: Sepsis is a clinical syndrome characterised by the systemic response to infection. It is a common problem in modern intensive care units and is associated with significant morbidity and mortality. Though the underlying cause of death is often multifactorial, refractory hypotension and cardiovascular collapse are frequently observed in the terminal phases of the condition. The aetiology of these cardiovascular abnormalities is complex but appears to be mediated by a circulating factor(s). The impact of sepsis upon left ventricular systolic function has been studied extensively. This may be because it is more readily assessed than diastolic function. Despite being increasingly appreciated as a contributor to morbidity and mortality in other clinical settings, there are scant data regarding the evaluation of left ventricular diastolic function in sepsis. Review of the haemodynamic monitoring literature reveals that many conventional measures of left ventricular filling, intravascular volume status and fluid responsiveness are influenced by ventricular diastolic (dys)function, such that interpretation can be challenging in critical care settings. In addition, many available techniques, such as pulmonary artery catheterisation, are invasive and potentially associated with risk to the patient. More robust and less invasive measures of left ventricular diastolic function and filling that can be applied within the intensive care unit (ICU) must be developed. The use of cardiac biomarkers, such as B-type natriuretic peptide (BNP), might represent a novel approach to evaluating left ventricular diastolic function and filling. BNP is released by the myocardium in response to wall stretch/tension. It has demonstrated value in the emergency department diagnosis of heart failure but interpretation of plasma BNP concentrations in critical care remains problematic. At least in part, this appears to relate to the significant number of potential confounders in patients with critical illness. Associations between BNP concentration and diastolic function have not previously been evaluated in severe sepsis and septic shock. The overall aim of this thesis is to investigate the usefulness of plasma BNP concentration in the evaluation of left ventricular diastolic function (including ventricular filling) in severe sepsis and septic shock. DIASTOLIC (DYS)FUNCTION IN SEPSIS: Review of the literature reveals that sepsis is associated with a spectrum of diastolic dysfunction. Characterisation of diastolic function in sepsis is challenging. In this regard, tissue Doppler imaging (TDI), offers promise. TDI is an echocardiographic technique that measures myocardial velocities, which are low frequency, high-amplitude signals filtered from conventional Doppler imaging. TDI has gained acceptance amongst cardiologists in the evaluation of diastolic function, particularly as a measure of ventricular relaxation and ventricular filling pressure; however, there are scant data regarding its use in critical care. We analysed echocardiographs from a large heterogeneous cohort of consecutive ICU patients (n=94) who had TDI as part of their clinically requested echocardiography. As well as supporting the feasibility of TDI in critically ill and mechanically ventilated patients, we demonstrated a wide range of TDI variables and a high prevalence of diastolic dysfunction using this modality. RODENT MODELS OF SEPSIS: We also sought to adapt, refine and evaluate rodent models of sepsis. Such models would allow control for a multitude of potential confounders commonly encountered in clinical sepsis. Two commonly employed rodent models of sepsis include caecal ligation and perforation (CLP) and endotoxin infusion. Comparison between CLP, sham and control groups demonstrated no difference in TDI or BNP. The observed changes in echocardiographic diastolic variables did not reflect those expected in sepsis and may be best explained by increases in heart rate rather than diastolic dysfunction per se. Endotoxaemia was associated with changes consistent with impaired myocardial relaxation (TDI) and reversible myocardial injury (histopathology), as expected in sepsis. BNP did not change significantly from baseline. This might be explained by the potential influence of fluid management upon BNP secretion. CLINICAL RESEARCH: The prediction of fluid responsiveness potentially prevents ineffective, excessive or deleterious intravenous fluid administration. Prospective evaluation of plasma BNP concentration in patients with septic shock found that it was not a predictor of a fluid responsive state. Furthermore, elevated BNP did not rule out a favourable response and therefore does not contraindicate a fluid challenge. Both impaired diastolic dysfunction, especially E/e’, and elevated BNP, have been associated with excess mortality in a range of cardiovascular diseases. These have not previously been compared in septic shock. In a cohort of patients with septic shock, E/e’ was a stronger predictor of mortality than cardiac biomarkers, including BNP. Fluid balance was an independent predictor of BNP in septic shock. OVERALL CONCLUSION: BNP appears not to be clinically useful in the evaluation of ventricular filling or diastolic function in sepsis. The association with fluid balance is a new finding and should be evaluated in a wider range of critically ill patients. In contrast to BNP, TDI appears to be a promising bedside tool in the evaluation of diastolic function and should be further evaluated in critical care.
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Quantification of cardiovascular flow and motion : aspects of regional myocardial function and flow patterns in the aortic root and the aorta /Kvitting, John-Peder Escobar, January 2004 (has links) (PDF)
Diss. Linköping : University, 2004.
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Annular dynamics of the human heart : novel echocardiographic approaches to assess ventricular function /Carlhäll, Carljohan, January 2004 (has links) (PDF)
Diss. Linköping : Linköpings universitet, 2004.
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Avaliação da sedação e dos efeitos cardiovasculares de duas doses de detomidina em muares / Evaluation of sedation and cardiovascular effects of two doses of detomidine in mulesMódolo, Tiago José Caparica [UNESP] 18 May 2018 (has links)
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Previous issue date: 2018-05-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A detomidina é um dos fármacos mais utilizados para a sedação de muares, porém não há dose estabelecida para esta espécie sendo indicado utilizar uma dose 50% maior que a indicada para equinos. Assim, o objetivo deste estudo foi avaliar a eficácia e os efeitos cardiovasculares da detomidina em muares comparando duas doses diferentes, a utilizada em equinos ( G1 - 0,02 mg/kg) e a dose 50% maior (G2 – 0,03 mg/kg). Para isso, foram utiizados 6 muares (2 machos e 4 fêmeas), adultos (339±27 kg), os animais receberam as duas doses com espaçamento mínimo de 7 dias, formando assim dois grupos experimentais com 6 animais cada. Antes da aplicação (M0) da detomidina pela via intravenosa e 5, 15, 30, 45 e 60 minutos após a aplicação (M5; M15; M30; M45; M60, respectivamente) foram avaliados frequência cardíaca, frequência respiratória, motilidade intestinal, altura da cabeça, além dos parâmetros ecocardiográficos: diâmetro interno do ventrículo esquerdo ao final da sístole e da diástole, fração de encurtamento, fração de ejeção, volume do ventrículo esquerdo ao final da sístole e da diástole, volume sistólico e débito cardíaco. A altura da cabeça do G2 permaneceu significativamente menor até o M60 quando comparado ao M0 do mesmo grupo, já do G1 ficou significativamente menor até o M45 quando comparado ao basal. O débito cardíaco do G1 foi significativamente menor nos M5, M15, M30 quando comparado ao M0 doG1, já do G2 permaneceu significativamente menor, quando compardo ao M0 do G2, do M5 ao M45. Concluiu-se que os muares que receberam dose 50% maior de detomidina permaneceram sedados por um período maior, porém os efeitos cardiovasculares também foram mais prolongados. / Detomidine is the drugs most used for sedation of mules, but there is no established dose for this species being indicated to use a dose 50% greater than indicated for horses. Thus, the objective of this study was to evaluate the efficacy and cardiovascular effects of detomidine in mules comparing two different doses, the used in horses (G1 - 0.02 mg / kg) and the 50% higher dose (G2 - 0.03 mg / kg). For this, 6 muares (2 males and 4 females), adults (339 ± 27 kg) were used, the animals received the two doses with a minimum spacing of 7 days, thus forming two experimental groups with 6 animals each. Before the application (M0) of detomidine intravenously and 5, 15, 30, 45 and 60 minutes after the application (M5, M15, M30, M45, M60, M60, respectively) were evaluated heart rate, respiratory rate, intestinal motility, height of the head, in addition to the echocardiographic parameters: internal left ventricular diameter at the end of systole and diastole, fraction of shortening, ejection fraction, left ventricular volume at the end of systole and diastole, systolic volume and cardiac output. The head height of G2 remained significantly lower until M60, whereas G1 was significantly lower up to M45, cardiac output of G1 was significantly lower in M5, M15, M30, whereas G2 remained smaller than M5 at M45. Concluding that mules receiving a 50% higher dose of detomidine remained sedated for a longer period, but the cardiovascular effects were also longer. / 140230/2014-9
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Comportamento do fluxo venoso pulmonar durante o ciclo respiratório fetalChemello, Keli January 2007 (has links)
Introdução- Os movimentos respiratórios têm influência na circulação fetal. Sua presença indica um sistema nervoso intacto, não deprimido, refletindo o bem-estar do concepto. Acredita-se que, em apnéia, a pressão exercida pelos órgãos intratorácicos no coração fetal, em particular os pulmões não expandidos, limita a distensibilidade ventricular. O padrão de fluxo das veias pulmonares, um parâmetro para avaliação Doppler-ecocardiográfica da função diastólica fetal, é determinado pelos eventos que ocorrem do lado esquerdo do coração, sendo influenciado pelas mudanças dinâmicas na pressão do átrio esquerdo criadas pela contração e pelo relaxamento do átrio e do ventrículo esquerdos. A impedância ao fluxo da veia pulmonar para o átrio esquerdo é representada pelo índice de pulsatilidade. Objetivo- Testar a hipótese de que o índice de pulsatilidade do fluxo venoso pulmonar fetal é menor na presença dos movimentos respiratórios fetais do que em apnéia. Métodos- Examinados 22 fetos normais de mães sem doença sistêmica, em apnéia (controles) e na presença de movimentos respiratórios fetais (casos). Os fetos foram examinados pela ecocardiografia pré-natal com Doppler e mapeamento de fluxo em cores. O índice de pulsatilidade da veia pulmonar foi obtido colocando-se a amostra volume do Doppler pulsado sobre a veia pulmonar superior direita ou inferior esquerda, e aplicando-se a fórmula velocidade máxima (sistólica ou diastólica)-velocidade pré-sistólica/velocidade média. Resultados- Os fetos apresentaram idade gestacional média de 28,9 ± 2,9 semanas. Na avaliação realizada nos fetos em apnéia as médias das velocidades sistólica, diastólica e pré-sistólica foram, respectivamente, 0,35 ± 0,08 m/s, 0,26 ± 0,07 m/s, 0,09 ± 0,03 m/s. Na avaliação realizada na presença de movimentos respiratórios fetais as médias das velocidades sistólica, diastólica e pré-sistólica foram, respectivamente, 0,33 ± 0,1 m/s, 0,28 ± 0,08 m/s, 0,11 ± 0,04 m/s. O índice de pulsatilidade da veia pulmonar médio, nos fetos em apnéia, foi de 1,25 ± 0,23 (1,69 a 0,82), e na presença de movimentos respiratórios fetais foi de 0,97 ± 0,2 (1,53 a 0,61). Conclusão- Demonstramos significante diminuição da impedância ao fluxo venoso pulmonar, representada pelo índice de pulsatilidade vascular, durante os movimentos respiratórios fetais, refletindo modificações da dinâmica atrial esquerda e da melhora complacência ventricular esquerda. / Introdution- Respiratory movements influence fetal circulation. Their presence indicates an intact, non-depressed nervous system, reflecting a good fetal clinical status. In apnea, the pressure of intrathoracic organs on the fetal heart, mainly the non-expanded lungs, limits ventricular distensibility. Flow pattern in pulmonary veins, a Doppler echocardiographic parameter in the assessment of fetal diastolic function, is determined by events occurring in the left heart and is influenced by dynamic changes in left atrial pressures created by left atrium and ventricle contraction and relaxation. Impedance to pulmonary venous flow to the left atrium is represented by the pulsatility index. Objective- To test the hypothesis that fetal pulmonary venous flow pulsatility index is lower during fetal respiratory movements than in apnea. Methods- Twenty-two normal fetuses of mothers without systemic disease were examined in apnea (controls) and in the presence of fetal respiratory movements (cases). Fetuses were examined by prenatal Doppler echocardiography with color flow mapping. The pulsatility index of the pulmonary vein was obtained placing the pulsed Doppler sample volume over the right upper or left lower pulmonary vein , and applying the formula [maximum velocity (systolic or diastolic)–pre-systolic velocity]/mean velocity. Results- Mean gestational age was 28.9 ± 2.9 weeks. During fetal apnea, mean systolic, diastolic and pre-systolic velocities were, respectively, 0.35 ± 0.08 m/s, 0.26 ± 0.07 m/s and 0.09 ± 0.03 m/s. In the presence of fetal respiratory movements, mean systolic, diastolic and pre-systolic velocities were, respectively, 0.33 ± 0.1 m/s, 0.28 ± 0.08 m/s and 0.11 ± 0.04 m/s. Pulsatility index pulmonary vein in apnea was 1.25 ± 0.23 (1.69 to 0.82), and during fetal respiratory movements it was 0.97 ± 0.2 (1.53 to 0.61). Conclusion- We showed a significant reduction in impedance of pulmonary venous flow, represented by pulmonary vein pulsatility index, during fetal respiratory movements, reflecting modifications of the left atrial dynamics and enhancement of left ventricular compliance.
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Effects Of A Novel, High-Intensity Aerobic Interval Training Program on Diastolic And Cardiovascular Function In Patients With Heart Failure With Preserved Ejection FractionJanuary 2012 (has links)
abstract: Heart failure is a major worldwide health concern and is the leading cause of hospitalization among elderly Americans. Approximately 50% of those diagnosed with heart failure have heart failure with preserved ejection fraction (HFPEF). HFPEF presents a therapeutic dilemma because pharmacological strategies that are effective for the treatment of heart failure and reduced ejection fraction have failed to show benefit in HFPEF. Long term moderate intensity exercise programs have been shown to improve diastolic function in patients HFPEF. High intensity interval training (HIIT) has been shown to improve diastolic function in patients with heart failure and reduced ejection fraction. However, the effects of high intensity interval training in patients with HFPEF are unknown. Fourteen patients with HFPEF were randomized to either: (1) a novel program of high-intensity aerobic interval training (n = 8), or (2) a commonly prescribed program of moderate-intensity (MOD) aerobic exercise training (n = 6). Before and after four weeks of exercise training, patients underwent a treadmill graded exercise test for the determination of peak oxygen uptake (VO2peak), a brachial artery reactivity test for assessment of endothelium-dependent flow-mediated dilation (BAFMD), aortic pulse wave velocity assessment as an index of vascular stiffness and two-dimensional echocardiography for assessment of left ventricular diastolic and systolic function. I hypothesized that (1) high-intensity aerobic interval training would result in superior improvements in FMD, aortic pulse wave velocity, VO2peak, diastolic function and, (2) changes in these parameters would be correlated with changes in VO2peak. The principal findings of the study were that a one month long high intensity interval training program resulted in significant improvements in diastolic function as measured by two-dimensional echocardiography [pre diastolic dysfunction (DD) grade - 2.13 + 0.4 vs. post DD grade - 1.25 + 0.7, p = 0.03]. The left atrial volume index was reduced in the HIIT group compared to MOD ( - 4.4 + 6.2 ml/m2 vs. 5.8 + 10.7 ml/m2, p = 0.02). Early mitral flow (E) improved in the HIIT group (pre - 0.93 + 0.2 m/s vs. post - 0.78 + 0.3 m/s, p = 0.03). A significant inverse correlation was observed between change in BAFMD and change in diastolic dysfunction grade (r = - 0.585, p = 0.028) when all the data were pooled. HIIT appears to be a time-efficient and safe strategy for improving diastolic function in patients with heart failure and preserved ejection fraction. These data may have implications for cardiovascular risk reduction in this population. / Dissertation/Thesis / Ph.D. Exercise and Wellness 2012
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