老年健康貓咪的脊椎心臟比率與心臟超音波數值的變化研究

Abstract

胸腔X光片與心臟超音波是重要且常被用於評估及診斷心臟疾病的影像工具。有許多關於胸腔X光片與心臟超音波的正常影像和因心臟疾病所造成之異常影像的研究，但是關於年齡對胸腔X光片與心臟超音波影像所造成的影響的研究並不多。119隻健康貓咪被納入本實驗以研究不同年齡層貓咪之胸腔X光片與心臟超音波是否會有變化以及會有什麼變化，這些貓咪被分為3組：年輕組（1-6歲）、中年組（7-10歲）、及老年組（大於10歲）。在胸腔X光片下，我們觀察到相較於年輕貓咪，中年及老年貓咪的心臟輪廓增加且心臟較為水平;在心臟超音波下，我們觀察到中年及老年貓咪的心室壁較厚（舒張期左心室游離壁及心室中隔）及僧帽瓣舒張早期最大血流流速、三尖瓣舒張早期及晚期最大血流流速及動脈流速皆較慢。本研究排除了可能造成這些變化的病理原因，包括全身性高血壓、甲狀腺機能亢進、及呼吸道疾病，因此這些在胸腔X光片與心臟超音波下所觀察到的變化可能是因貓咪正常老化而造成的影響。

Thoracic radiographs and echocardiography are important and commonly used diagnostic methods of cardiac imaging. Studies regarding normal and abnormal radiographic and echocardiographic signs of feline heart have been investigated. However, the effects of age on radiographs and echocardiography is poorly understood. One hundred and nineteen clinically healthy cats between 1-17 years old were prospectively studied to assess whether and how radiographic and echocardiographic variables differ across age bands in clinically healthy cats. These cats were categorized into 3 groups: adolescent-adult (1-6 years), middle-aged (7-10 years), and geriatric (older than 10 years). On radiographs increased cardiac silhouette horizontally aligned heart was observed in middle-aged and geriatric groups compared to adolescent-adult groups. On echocardiography, increased cardiac wall thickness (LVPWd and IVSd) and decreased MEVp, TEVp, TAVp, and AVp were found in middle-aged and geriatric cats. Possible pathologic causes, like systemic hypertension, hyperthyroidism, and respiratory diseases were excluded from the study. Thus, the differences observed between healthy geriatric cats and younger cats can be considered to be age-related changes.