This 21- year- old man was admitted due to sudden onset of chest tightness and shortness of breath at PM 7: 45 on May 28

 This 21- year-old man was robust in the past without known major systemic diseases. He said that he had two episodes of cold sweating in teenage but neither one was associated with chest tightness. No family history of heart disease was known. In the past one year, he began to experience chest discomfort and palpitations after exercise and the symptoms were relieved 2- 3 minutes after taking a rest. Neither chest pain nor dyspnea was noted and he didn’t pay much attention to the discomfort. However, he suffered from sudden onset of chest tightness, palpitations and shortness of breath while he was sitting and reading at PM 7: 45 on May 28. Cold sweating, dizziness, tinnitus and near fainting sensation were also noted. He was then escorted to our ES at PM 8: 16 while the discomfort subsided slightly. On arrival at emergency room, BP was 147/93 mmHg, and HR 75/min. ECG (05/28 20:29) showed ST depression over leads II, III, aVF (Figure 1, 2) and the blood test revealed serial elevation of cardiac enzyme (CK/CKMB 5/28: 236/16.4, 5/29: 341/28.8, 5/29: 441/38.6). Under the impression of non-Q myocardial infarction, he was transferred to our CCU.

 On examination, his consciousness was clear. The blood pressure was 133/73 mmHg, pulse, 84/min; respirations, 20/min; temperature 36.5°C. The breath sounds were clear and the heart sounds were regular without tachycardia. No pitting edema was noticed over extremities.

Aspirin and heparin were administered on May 29 and the chest discomfort improved subjectively. Enzyme peaking was achieved at 4AM on May 29 (9hrs post chest tightness). Cardiac catheterization (Figure 6) performed on May 29 demonstrated patent coronary arteries and good LV contractility with normal LV size. Localized myocarditis at inferior wall was considered and anti-platelet agents, NTG and Heparin were discontinued since May 30. He was transferred to general ward on May 31 and then discharged on June 2.

Another episode of chest tightness along with palpitations and shortness of breath happened at PM 5: 00 on June 13. He visited our emergency room within 5 minutes where ECG (Figure 3) was taken immediately. Cardiac enzyme was also checked and elevated troponin I was found. Adenosine 18 mg was given intravenously and the tachycardia was terminated. The ECG followed 2 minutes later showed ST depression over leads II, III and aVF (Figure 4). Two hours after the tachycardia stopped, the ECG (Figure 5) showed normal sinus rhythm without any ST-T change. He was followed at NTUH OPD and will receive EPS later.

Laboratory data:
[Hematologic laboratory values]

病例分析
這是一個二十一歲的年輕男性胸痛病人,有心悸及冷汗暈眩之伴隨症狀,但無明顯冠狀動脈疾病危險因子.在急診時之鑑別診斷需考慮如氣胸,肺炎,心肌炎,心律不整等等.精神官能症在年輕人雖很有可能,但不可作為唯一之考量.簡易的心電圖,胸部X光及心臟酵素檢查仍必須完成.

以本病例而言,一開始之心電圖在下壁有ST 段低下的情況,X光並無肺炎及氣胸之情況,故心臟之問題仍需優先考慮.此時系列的心電圖和酵素之追蹤是最重要的.當酵素上升時而心電圖有系列變化時,在心肌受損的診斷下給予急性冠狀動脈症候群的處理是合理的.進一步血管攝影檢查是有必要的.

 關於心律不整的部分,發病時的心電圖是診斷時最重要的,有時單從臨床症狀是無法作確實診斷.故在門診遇到這種病人,應建議於症狀發作時盡快至最近的醫療院所或檢驗所取得十二導程心電圖,以為診斷之工具.