- 期刊
Relevance Assessment of Clinical Symptoms and Classification of Coronary Artery Anomalies in Sixty-four Multidetector Computed Tomography
利用64切電腦斷層攝影探討冠狀動脈異常的分類與臨床表現的相關性
摘要
冠狀動脈異常（coronary artery anomaly, CAA）可能屬良性或惡性，惡性的CAA 會引起冠狀動脈疾病、心肌缺氧甚至猝死。自1990 年起已有許多利用心導管檢查分類的方式。本研究的主要目的為利用64 列電腦斷層攝影（multidetector computed tomography, MDCT）來探討CAA 的分類與臨床表現的相關性。本研究收集2006 年6 月到2009 年6 月進行64列電腦斷層冠狀動脈攝影的1,974 位受檢者（1,351 男性，623 位女性，平均年齡50.5±10.9 歲）冠狀動脈電腦斷層攝影，受檢者來源包括有冠狀動脈症狀患者及自費做健康檢查的成人。所有影像由一位放射科醫師及一位心臟內科醫師判讀。篩選出有CAA 的受檢者，利用Rigatelli 等於2003 年提出的CAA 臨床相關性之四類分級：「良性、有意義的、嚴重的及危急的」，進行異常的分類。CAA 病人(心肌橋除外)的臨床症狀例如：胸痛、胸悶等皆列入評估。追蹤時間從8 個月到46個月（平均為31.3±12 個月）。檢查過程中利用三種掃描方式：回溯性心電圖門控配合心電圖控制之管電流調控（ECG tubecurrent modulation, ETCM）70%-80% R-R 間期及40%-80% R-R 與回溯性心電圖門控三種掃描方式，比較其有效劑量及節省輻射劑量的比例。本研究中共發現63 位CAA 病人，其發生率為3.19%。臨床相關性分類為良性的有37 位，有意義的有13 位，嚴重的有10 位，危急的有3 位，另有10 位無法追蹤其臨床症狀。有追蹤紀錄的53 人皆無心因性死亡；分類嚴重等級的病人多會進行核醫檢查，另有13 位有進行心導管檢查，檢出之冠狀動脈異常與MDCT 結果相符。分析追蹤病人的臨床症狀及CAA 嚴重度的關係，發現所有追蹤的臨床症狀與嚴重度沒有顯著差異（P ＞ 0.05）。可能的原因是冠狀動脈異常的數量較少，且大多數來自於健康檢查。但本研究CAA 發生率較心導管高，所以MDCT 是診斷冠狀動脈疾病的首選工具。輻射劑量以ETCM 70%-80% R-R 間期的有效劑量最低且節省輻射劑量的比例最高，與另兩種掃描方式相比皆有統計意義（P ＜ 0.001）。
並列摘要
Coronary artery anomalies (CAAs) can be benign or malignant and may result in coronary artery disease, myocardial ischemia, and sudden death. Several classifications of CAA by cardiac catheterization have been reported since 1990. The purpose of this study was to assess clinical symptoms relevant to classification of CAAs by using sixty-four multidetector computed tomography (MDCT). A total of 1,974 subjects (1,351 male, 623 female, mean age of 50.5 ± 10.9 years) who had undergone 64-MDCT from June 2006 to June 2009 were identified retrospectively. CT images were reviewed for coronary artery variants and anomalies. Data were interpreted by a radiologist and a cardiologist. The CAAs were classified into four groups: benign, relevant, severe, and critical that Rigatelli proposed in 2003. The clinical symptoms such as chest pain, chest tightness of the subjects with CAAs (except myocardial bridging) were evaluated. The follow-up time was from eight to forty-six months (mean time: 31.3 ± 12 months). Three scan protocols were used for these patterns: ECG tube current modulation (ETCM) with 70-80% exposure window, 40-80% exposure window and retrospective ECG-gating. Among them, the radiation dose and exposure saving were compared. The incidence rate of CAA was 3.19% (n = 63). The clinical relevance classifications are benign (n = 37), relevant (n = 13), severe (n = 10), and critical (n = 3). Ten subjects were excluded because of lack of follow-up information, and no cardiac death occurred among the fifty-three follow-up patients. Most subjects classified as severe were arranged for nuclear medical examination. Thirteen of CAAs have done cardiac catheterization, and the results were compatible with MDCT. There is no significant difference between the classification of CAAs and the clinical symptoms (P ＞ 0.05). The possible reason is the small amount of our CAAs, and most subjects are for physical examination. Otherwise, the incidence rate of CAA in MDCT is higher than cardiac catheterization. It can be used as the first imaging modality in diagnosing CAAs. Subjects using ETCM with 70-80% exposure window can lower radiation dose and make more dose saving statistically significantly (P ＜ 0.001)