高憲立2006-07-262018-07-112006-07-262018-07-111999http://ntur.lib.ntu.edu.tw//handle/246246/23430評估急性心肌梗塞病患之預後時，多條血管之冠狀動脈病變是一重要因素。直至目前，冠 狀動脈攝影仍被視為標準檢查方式。然而，許多非侵襲性檢查，包括運動心電圖、鉈201 心肌 灌流掃瞄及催迫式心臟超音波已逐步發展並應用於多血管冠狀動脈心臟病之預測。但以實用觀 點而言，仍有許多臨床上的限制。首先，對於心肌梗塞病患，這些催迫式檢查在急性期仍有相 當程度的危險性。其次，對於仍需留觀於加護病房之患者，運動心電圖及鉈201 心肌灌流掃瞄 無法適用。第三，催迫式心臟超音波檢查常於某血管灌流範圍之心肌收縮異常時即停止下一階 段之檢查，因此，往往只能偵測到具有最嚴重缺氧程度之單一冠狀動脈，無法同時對三條冠狀 動脈進行評估。超音波組織特性分析乃利用心肌組織對於超音波音束之散射作用，將所有逆散 射之訊號予以總和，視為反射之能量顯示。於正常心肌組織，此反射能量之大小會隨心臟收縮 與舒張，而有週期性之變化，於收縮時達到最小，而於舒張時達到最大。但於心肌缺氧或梗塞 時。此週期變化之大小會減少，谷底值出現之時期亦會延後。然而，若即時予以再灌流治療， 此變化將比對心肌收縮程度之影響更早恢復。 本計畫乃利用超音波組織特性分析(UTC)及催迫性超音波心圖檢查(DSE)，預測急性心肌梗 塞(AMI)病患是否併有多條血管之冠狀動脈病變，並且針對再灌流治療於梗塞血管之成效予以 評估。共有三十位病人於AMI 後之8.3±3 天內接受UTC 及DSE 檢查。在UTC 檢查中， phase-weighted variation 可分別出一塊心肌組織是否還存有冠狀動脈灌流不足或已結疤 (p<0.001)。在存活而不具缺氧狀況的心肌組織其數值則與正常心肌組織類似(p=0.453)。利用 5.8 作分界，用UTC 之phase-weighted variation 對存活但仍殘存心肌缺氧組織之判定，其診斷 性之靈敏度、特異性及精確度分別是75%，100%及90.2%。而當此心肌接受再灌流治癒後其 phase-weighted variation 數值極小，且與冠狀動脈血流是否暢通無關。 因此，吾人發現UTC 對偵測不具狹窄冠狀動脈的梗塞心肌非常有效，它可用以篩檢急性心 肌梗塞後患者是否須接受導管或冠狀動脈穿通術之依據。Background The identification of viable myocardium and residual ischemia in patients with acute myocardial infarction (AMI) has important prognostic implications. The ultrasonic tissue characterization (UTC) with integrated backscatter has been shown to be a sensitive marker of myocardial ischemia and infarction. After reperfusion of occluded coronary artery, the cardiac cyclic-dependent variation of integrated backscatter restores its amplitude modulation before the recovery of myocardial contractility. It implies that the promising method can be used to identify stunning myocardium. Methods and Results UTC and dobutamine-atropine stress echocardiography (DSE) were performed 8.3±3 days after AMI in 30 patients. The DSE was considered as a reference to identify viable myocardium and residual ischemia. After coronary intervention, both modalities were performed to evaluate the influences of residual stenosis. The parameter obtained from UTC, phase-weighted variation, could differentiate the myocardium with residual coronary stenosis or nonviable from the viable myocardium without residual coronary stenosis (p<0.001). The latter has the similar value to that of normal control group (p=0.453). Using the cutoff value of 5.8, the sensitivity, specificity, and accuracy for detecting viable myocardium without residual infarct-related artery stenosis were 75%, 100%, and 90.2%, respectively. The phase-weighted variation of viable infarction zone restored after the coronary stenosis was relieved. Contrarily, the nonviable myocardium had small phase-weighted variation irrelevant to the patency of infarct-related artery. Conclusions The UTC was a very useful method to identify the viable myocardium of which infarct-related artery was free from residual stenosis. It can be used as a predischarge screening tool for risk stratification and is helpful in constructing the intervention strategy.application/pdf138220 bytesapplication/pdfzh-TW國立臺灣大學醫學院內科超音波組織特性分析催迫式心臟超音波心肌梗塞冠狀動脈心臟病再灌流治療myocardial infarctionechocardiographyischemiastunningmyocardialreporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/23430/1/882314B002331.pdf