儘管心力衰竭的診斷和治療已取得了長足進步，但是心力衰竭依然是目前主要的致殘和致死病因。而且，隨著人口的老齡化，心力衰竭的發病率不斷上升。然而心力衰竭的快速診斷、心功能評價以及患者的危險分層依然面臨眾多挑戰。Acoustic cardiography 是一項經濟簡單的新技術。憑藉獨有的雙功能感測器，這項技術可以同時評估收縮間期（systolic time intervals）以及舒張期心音（diastolic heart sounds）。這項技術提供的主要參數包括：第三心音分數（S3 score；第三心音存在的可能性），電機械時間（EMAT, electromechanical activation time；從心電圖Q 波到心音圖第一心音的時間）及電機械時間比例（%EMAT；電機械時間占整個心動週期的比例），收縮障礙指數（SDI, systolic dysfunctionindex）。本論文主要涵蓋Acoustic cardiography 在心力衰竭患者中如下三個方面 的應用： / 一、心力衰竭的診斷和不同亞型的識別 / 本研究入組了 94 名高血壓但無心力衰竭患者、109 名射血分數正常的心力衰竭患者以及89 名射血分數減低的心力衰竭患者，我們發現%EMAT 可以鑒別射血分數正常的心力衰竭和高血壓患者。另一方面，SDI 是鑒別分射血分數正常和射血分數減低患者的最好指標。 / 二、心力衰竭患者心功能障礙嚴重程度評估 / 此研究共招募 94 名高血壓患者和127 名射血分數減低的心力衰竭患者。結果顯示：SDI 可以鑒別射血分數減低的心力衰竭和高血壓患者。亞組分析顯示：SDI 可以區分射血分數嚴重減低和中度減低的心力衰竭患者；S3 score 可以識別伴舒張功能嚴重障礙的心力衰竭患者。 / 三、心力衰竭患者的危險分層 / 共計 474 名心力衰竭患者被納入此研究，平均隨訪時間484±316 天，169名患者死亡，其中125 名死於心臟病。SDI 和S3 score 都是全因死亡率的獨立預測因數；Kaplan Meier 分析顯示：SDI ≥ 5 或S3 score ≥ 4.12 的心力衰竭患者的生存率顯著降低。 / 通過以上三個方面的研究，我們發現這項新技術有助於（1）心力衰竭的診斷和不同亞型的識別；（2）評估心力衰竭患者的心功能障礙嚴重程度，進而發現其中的高危人群；（3）心力衰竭患者的危險分層。因此，這項新技術有望在心力衰竭患者的管理中扮演早期診斷、評估以及危險分層的重要角色。 / Despite recent advances in its management, heart failure remains a major cause of disability and death and its prevalence is still increasing as the population ages. However, rapid and accurate bedside diagnosis, evaluation as well as risk stratification of heart failure still remain challenging. / Acoustic cardiography (AUDICOR, Inovise Medical, Inc., Portland, OR, USA) is a novel and user friendly equipment which can be used in a wide variety of clinical conditions. With proprietary dual-functional sensors, this technology permits simultaneous acquisition of detailed information regarding systolic time intervals and diastolic heart sounds and provides a computerized interpretation of the findings. Major acoustic cardiographic parameters include S3 score (probability that the third heart sound exists), electromechanical activation time (EMAT, interval from Q wave to the first heart sound; %EMAT is the proportion of cardiac cycle that EMAT occupies), and systolic dysfunction index (SDI= exp [S3 score/10] x QRS interval x QR interval x %EMAT).This thesis will cover 3 aspects of clinical application of acoustic cardiography in heart failure patients. / I. Identification of heart failure and its phenotypes / We performed one study involving 94 patients with hypertension without heart failure, 109 patients with heart failure with normal ejection fraction (HFNEF, EF > 50%) and 89 patients with heart failure and reduced ejection fraction (HFREF, EF < 50%). We found that %EMAT significantly differentiated HFNEF from hypertension. Whereas SDI out-performed the other acoustic cardiographic parameters in differentiating HFREF from HFNEF. / II. Assessment of HFREF patients at high risk by evaluating the severity of left ventricular (LV) systolic and diastolic dysfunction / Ninety-four hypertensive patients without heart failure and 127 HFREF patients (EF < 50%) were consecutively recruited for the study. SDI significantly differentiated HFREF from hypertension. In subgroup analysis, SDI discriminated HFREF patients with severely impaired EF (EF ≤ 35%) from those with moderately impaired EF (35% < EF <50%). S3 score > 4.67 identified HFREF patients with restrictive LV filling pattern. / III. Risk stratification in patients with heart failure / A total of 474 patients hospitalized for heart failure were enrolled into our study. During a mean follow-up time of 484±316 days, 169 (35.7%) patients died and 125 (26.4%) of them died of cardiac causes. After controlling for other potential confounders, we found that S3 score ≥ 4.12, and SDI ≥ 5 were both independent predictors for all-cause mortality. Kaplan-Meier analysis showed that heart failure patients with SDI ≥ 5 or S3 score ≥ 4.12 had a significantly lower survival rate than those with lower SDI or S3 score. / In summary, this bedside technology offers a wide variety of clinical applications in (1) identification of heart failure and its phenotypes; (2) assessmet of HFREF patients at high risk by evaluating the severity of LV systolic and diastolic dysfunction; (3) risk stratification in patients with heart failure. Thus, acoustic cardiography is likely to be helpful in the management of heart failure patients, acting as an early detection, evaluation and risk-stratification tool. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wang, Shang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 123-135). / Abstract also in Chinese. / DECLARATION OF ORIGINALITY --- p.i / ACKNOWLEDGEMENTS --- p.ii / PUBLICATIONS RELATED TO THIS THESIS --- p.iv / Full publications --- p.iv / Conference presentations --- p.v / TABLE OF CONTENTS --- p.vi / LIST OF TABLES --- p.xi / LIST OF FIGURES --- p.xiii / LIST OF ABBREVIATIONS --- p.xv / ABSTRACT --- p.xviii / 論文摘要 --- p.xx / Chapter PART I --- LITERATURE REVIEW --- p.1 / Chapter Chapter 1 --- Introduction to Acoustic Cardiography --- p.2 / Chapter 1.1 --- History of auscultation, phonocardiography --- p.2 / Chapter 1.2 --- STIs --- p.3 / Chapter 1.2.1 --- Conventional STIs --- p.3 / Chapter 1.1.2 --- Echocardiographic STI --- p.5 / Chapter 1.3 --- Acoustic cardiography --- p.7 / Chapter 1.3.1 --- ECG parameters of acoustic cardiography --- p.11 / Chapter 1.3.2 --- Systolic parameters of acoustic cardiography --- p.12 / Chapter 1.3.3 --- Diastolic Parameters of acoustic cardiography --- p.13 / Chapter 1.4 --- Comparison between acoustic cardiography and traditional phonocardiography --- p.19 / Chapter Chapter 2 --- Clinical Application of Acoustic Cardiography --- p.27 / Chapter 2.1 --- Mechanism of generation of S3 and S4 --- p.27 / Chapter 2.2 --- Prevalence of S3 and S4 --- p.28 / Chapter 2.3 --- Clinical auscultation of S3 and S4 problems --- p.29 / Chapter 2.4 --- Rapid identification of heart failure or LV dysfunction --- p.32 / Chapter 2.4.1 --- S3 and S4 --- p.32 / Chapter 2.4.2 --- EMAT --- p.33 / Chapter 2.4.3 --- SDI --- p.34 / Chapter 2.4.5 --- Other derived acoustic cardiographic parameters --- p.34 / Chapter 2.5 --- Predicting elevated LV filling pressure --- p.35 / Chapter 2.6 --- Improving diagnostic utility of BNP in detection of heart failure or LV dysfunction --- p.36 / Chapter 2.7 --- Hemodynamic correlations of acoustic cardiographic parameters --- p.37 / Chapter 2.8 --- Prognostic value of acoustic cardiography --- p.38 / Chapter 2.9 --- Cardiac resynchronization therapy --- p.39 / Chapter 2.10 --- Detection of ischemia --- p.40 / Conclusions --- p.42 / Chapter PART II --- STUDIES ON APPLICATION OF ACOUSTIC CARDIOGRAPHY --- p.48 / Chapter Chapter 3 --- Acoustic Cardiography Helps to Identify Heart Failure and Its Phenotypes --- p.49 / Introduction --- p.49 / Methods --- p.50 / Participants and study design --- p.50 / Echocardiography --- p.51 / Acoustic cardiography --- p.52 / Assessment of reproducibility --- p.55 / Statistical analysis --- p.55 / Results --- p.56 / Characteristics of study subjects --- p.56 / Acoustic cardiographic and echocardiographic characteristics --- p.59 / Diagnostic characteristics of acoustic cardiography --- p.64 / Analysis of covariance results --- p.68 / Inter-operator reproducibility --- p.68 / Discussion --- p.68 / Chapter Chapter 4 --- Rapid Bedside Identification of High-Risk Population in Heart Failure with Reduced Ejection Fraction by Acoustic Cardiography --- p.72 / Introduction --- p.72 / Methods --- p.73 / Study population --- p.73 / Echocardiography --- p.73 / Acoustic cardiography --- p.74 / Assessment of reproducibility --- p.74 / Statistical analysis --- p.74 / Results --- p.75 / Baseline characteristics of study subjects --- p.75 / Acoustic cardiographic and echocardiographic characteristics --- p.78 / Diagnostic test characteristics of acoustic cardiography --- p.84 / Analysis of covariance results --- p.89 / Inter-operator reproducibility --- p.89 / Discussion --- p.89 / Chapter Chapter 5 --- Prognostic value of Acoustic Cardiography in Risk Stratification of Patients With Heart Failure --- p.93 / Introduction --- p.93 / Methods --- p.94 / Study population --- p.94 / Acoustic cardiography --- p.94 / Echocardiography --- p.94 / Endpoint --- p.95 / Assessment of reproducibility --- p.95 / Statistical analysis --- p.95 / Results --- p.96 / Study population --- p.96 / All-cause mortality --- p.100 / Cardiac death --- p.100 / Subgroup analysis in 232 patients undergoing echocardiography --- p.107 / Inter-operator reproducibility --- p.107 / Discussion --- p.114 / Strengths and potential limitations --- p.115 / Chapter PART III --- CONCLUSIONS --- p.117 / Chapter Chapter 6 --- Summary of the Present Studies --- p.118 / Chapter I. --- Identification of heart failure and its phenotypes --- p.118 / Chapter II. --- Assessment of HFREF patients at high risk by evaluating the severity of LV systolic and diastolic dysfunction --- p.119 / Chapter III. --- Risk stratification in patients with heart failure --- p.119 / Chapter Chapter 7 --- Future Research Directions --- p.121 / References --- p.123
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_328514 |
| Date | January 2012 |
| Contributors | Wang, Shang, Chinese University of Hong Kong Graduate School. Division of Medical Sciences. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, bibliography |
| Format | electronic resource, electronic resource, remote, 1 online resource (xxi, 135 leaves) : ill. (chiefly col.) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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