斑點追蹤式心臟超音波評估小型犬退化性瓣膜疾病之左心功能

Evaluation of Left Ventricular Function in Small Breed Dogs with Mitral Valve Disease by Using Conventional and Speckle Tracking Echocardiography

吳彥貞(Yen-Chen Wu)

指導教授 ： 黃慧璧

國立臺灣大學/獸醫專業學院/獸醫學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.01504

摘要

退化性瓣膜疾病為中老年小型犬最常發生的心臟疾病。病變的瓣膜造成二尖瓣閉鎖不全，進一步引發左二尖瓣間的逆流。隨著退化性瓣膜疾病的發展，嚴重的逆流造成左心房、心室變形擴大，影響患犬心臟的收縮以及舒張功能，同時可能造成鬱血性心衰竭的發生。本論文包含兩個部分，分別為以傳統心臟超音波以及斑點追蹤式心臟超音波評估罹患退化性瓣膜疾病小型犬的左心室收縮功能，以及左心室舒張功能。第一篇收縮功能的研究結果顯示，患犬的斑點追蹤式心臟超音波結果相較於正常的犬隻低下，相對於傳統超音波評估的左心收縮功能其結果沒有太大的統計差異出現 ;左心的長軸運動相較於短軸運動較容易受到此疾病的影響。第二篇舒張功能研究顯示，斑點追蹤式心臟超音波有助於在鬱血性心衰竭時評估患犬的左心舒張功能。總和兩篇研究結果發現，斑點追蹤式心臟超音波可彌補傳統超音波不足之處，並可作為提供評估左心的收縮以及舒張功能的有效診斷工具。

關鍵字

退化性瓣膜疾病 ； 斑點追蹤式心臟超音波 ； 左心功能

並列摘要

Myxomatous mitral valve disease (MVD) is characterized by vavular myxomatous degeneration and is the most common heart disease in small breed dogs. The affected valves result in leakage of mitral valves (mitral regurgitation). As the severity of mitral regurgitation progresses, dogs with MVD eventually develop dilation of left ventricle and atrium, impairment of the systolic and diastolic function, and may cause congestive heart failure (CHF). In this study, small breed dogs with MVD were classified into two groups: MVD with CHF and MVD without CHF. The aim of this study was to evaluate the systolic function and diastolic function in small breed dogs with MVD by using conventional and two-dimensional speckle tracking echocardiography (2D-STE).
Longitudinal and circumferential strains and strain rates decreased and altered in dogs with MVD while no significant differed in fractional shortening and ejection fraction. Besides, attenuation of STE-derived longitudinal strain rates were prior to that of circumferential strain rates in severe mitral regurgitation. In the present study, 28% (24 out of 84) of 2D-STE variables significantly altered in dogs with MVD, compared with healthy controls. Regional decreased early diastolic strain rate of left ventricular longitudinal deformation was detected by 2D-STE in contrast with insignificantly different findings by tissue Doppler examination. Results of this study indicated that conventional echocardiography combined with 2D-STE could help to investigate the global LV systolic and diastolic function in dogs with MVD.

並列關鍵字

Mitral Valve Disease ； Speckle Tracking Echocardiography ； Left Ventricular Function

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