A 51-year-old male patient with chest pain and dyspnea(the 40th case)

，， 100853，

A 51-year-old male patient with chest pain and dyspnea(the 40th case)

Instituteof Geriatirc Cardiology，Chinese PL A General Hospital，Beijing100853，China

Case presentation

A 51-year-old man was admitted to hospital on Dec.23，2008 because of a 5-day history of chest and back pain，and dyspnea.On Dec.18，2008，the patient suffered from pain in right legs accompanied with movement disturbance when he defecated.Two hours later，the right leg pain and paralysis relieved，but chest and back pain appeared，and was exacerbated by deep inhalation，which was also accompanied with sweating and shortness of breath，but with no radiation pain，palpitations，nausea，or vomiting.Four days later，chest and back pain was relieved，but dyspnea still existed.The patient was then admitted to the Emergency Department of Affiliated Hospital，Chengde Medical College.The brain CT imaging was normal.The routine blood tests showed that white cell count was 23.23×109/L，and neutrophils 86.5%.The myocardial enzymes spectrum was normal.The ultrasonography of kidneys，bladder and ureters was also normal.The diagnosis of upper respiratory tract infection was given，and antibiotics were administrated.But after two-day treatment，the shortness of breath was still not relieved.For definite diagnosis and further treatment，the patient was admitted to Emergency Department，Chinese PLA General Hospital.The arterial blood gas analysis showed PO251.9 mmHg(1 mmHg=0.133kPa)，PCO226.5mmHg，pH 7.404，HCO-3 16.2 mmol/L，BE-7.2 mmol/L.The routine blood test showed white cell count 14.04×109/L，neutrophils 77.8%.And D-dimer 8.95mg/L.Blood biochemical tests showed TB 53.6 μ mol/L ，IB 19.3 μ mol/L ，serum creatinine 159.9 μ mol/L ，urea nitrogen 11.24 mmol/L，and potassium 3.20 mmol/L.The chest X-ray examination reported bilateral pleural effusions.The transabdominal ultrasonography(TAS)showed widening of hepatic vein，bilateral pleural effusions and ascites.The diagnosis of pulmonary embolism was suggested.The patient was transferred to Institute of Geriatric Cardiology，Chinese PLA General Hospital with the supposed diagnosis of"chest pain with undefined cause".

The patient had a 3-year history of hyertension，and the blood pressure was not under satisfactory control.He denied history of angina and deep venous thrombosis.The body temperature was 36.7℃，pulse rate 105/min，respiration rate 18/min，blood pressure 171/100 mmHg.No moist rales were auscultated，but the respiratory sounds were weak over both lung fields and disappeared at the lower part of lungs.Cardiac rhythm was regular，the heart rate was 105/min，and the first heart sound was weak.No cardiac murmur or pericardial rub was detected on auscultation.The abdomen was flat，soft and no tenderness.The liver was not palpable.There was no shifting dullness and edema of legs.The nervous system had no abnormality.Electrocardiographic examination showed sinus tachycardia and Q Ⅲ，avF.A transthoracic echocardiogram showed pericardial effusions，but no left ventricular hypertrophy or left ventricular segmental wall-motion abnormalities.Pulmonary embolism was the initial diagnosis，and low molecular weight heparin(LMWH)was given to the patient at a dose of 60mg every 12 hours.But lower limb venous ultrasound and perfusion lung scan didn't confirm the diagnosis of pulmonary embolism.LMWH administration was stopped.The ultrasound of renal artery，iliac artery and vein in legs were normal.Chest MRI showed aortic dissection.After consulting vascular surgeon，CT angiography(CTA)was performed and the descending aortic dissection，which originated in intimal tears just distal to the left subclavian artery，was identified.

Clinical discussion

Dr.Chen Yanming：The results of cardiac biomarkers and ECG excluded the possibility of acute myocardial infarction and acute pericarditis.The key point was the differentiation diagnosis of aortic dissection from pulmonary embolism.(1)Chest pain，dyspnea，sinus tarchycardia，hypoxia，the elevation of D-dimer，widening of liver veins and ascites provided clues to the diagnosis of pulmonary embolism.So on the first admission day，LMWH was administered subcutaneously.But no deep venous thrombosis was found in the lower extremities，and the perfusion lung scan excluded the initial diagnosis on the second admission day.(2)The patient had a 3-year history of hypertension，which was not controlled well.The chest pain was accompanied with right leg paralysis.MRI of ascending aortic dissection and CTA confirmed the diagnosis of aortic dissection.But there were a few questions about the diagnosis.(1)whether the aortic dissection could lead to dyspnea and pleural effusions.(2)Vascular CTA and angiography indicated that right renal artery and bilateral iliac artery were involved，but the ultrasonography was normal.Then what is the significance of vascular ultrasound in aortic dissection?(3)T he patient reported renal dysfunction，bad-controlled blood pressure，hypopotassemia，and right leg paralysis，so secondary hypertension was considered.Then what is the reason for the secondary hypertension?(4)What is the reason for white blood cell increase and red blood cell decrease?(5)What are the other disorders which need differentiation from aortic dissection in this patient?

Dr.Gao Lei：(1)Aortic dissection may cause blood exudation and lead to pleural，abdominal，and cardiac effusions.But dropsy of multiple serous cavities was seldom reported.Pleural effusions could cause dyspnea and hypoxia.(2)Transoesphageal echocardiography is sensitive and specific for ascending aortic dissection，which can show the site of intimal tears，blood flow of real and false cavity，aortic insufficiency，pleural effusion and blood flow of branches of aortic artery.But it is not sensitive and specific for descending aortic dissection.In this case，the renal and iliac arteries were involved，but the TAS didn't reveal abnormality，which showed that TAS had limited sensitivity for the diagnosis of descending aortic dissection.(3)If the artery which supplies the blood for nerve was involved，the feeling and movement of legs could disappear.This can explain the right leg paralysis of the patient.(4)According to renal ultrasound，we can speculate that the ischemia of the kidneys caused the elevation of serum creatinine，hypokalemia and activation of RAS system，and that is the reason for the hardcontrolled blood pressure.(5)White blood cell counts are usually elevated and hemoglobin reduced in patients with aortic dissection.It has been reported that they are related to the prognosis of aortic dissection.(6)An elevated D-dimer is a sensitive marker for pulmanory embolism.Unfortunately，it is not very specific.Its elevation is also observed in patients with acute myocardial infarction and aortic dissection.

Dr.Xueqiao：After admission，the key point for the patient was the differential diagnosis between aortic dissection and pulmonary embolism.The electrocardiographic findings in patients with aortic dissection are usually nonspecific.The chest X-ray film often suggests the diagnosis of dissection，but cannot identify it is on earth ascending aorta or descending aorta that is involved，and the sensitivity is low.CT and MRI both have high accuracy for identifying aortic dissection.Especially，CTA has important significance for differential diagnosis between pulmonary embolism and aortic dissection.Moreover，the level of serum creatinine(159.9 μ mol/L)was not a contraindication for CT angiography.If the renal function was impaired due to aortic dissection，it can be reversed by early diagnosis and treatment.What's more，CTA is very important for guiding stent selection.So，timely CTA can significantly shorten the time to get final diagnosis.

Dr.ZhaoY usheng：Aortic dissection had variable manifestations，including the severe pain in chest，back or abdomen，hypertension，the ischemia of organs(spinal cord，limbs，and kidneys)，the rupture of dissection(pericardial effusions，ascites，hemoptysis and hematemesis)，aortic insufficiency，and spasmophonia，etc.Even in some high level hospitals，miss diagnosis was reported in about 38%of the patients with aortic dissection，and the diagnosis was confirmed by autopsy in 28%patients.So it is not easy to diagnose this illness early.In this case，besides pulmonary embolism and aortic dissection，other diseases should also be considered.(1)Connective tissue disease also can manifest hypertension，renal dysfunction，fever，hypoxia and pleural effusions.For example，systemic lupus erythematosus also can cause aortic dissection.Patient's medical history and laboratory tests are quite useful for the differential diagnosis.(2)When hypertension was combined with right limb paralysis，stroke should be considered.When the aorta branches，such as carotid artery，vertebral artery，were involved in aortic dissection，stroke often happened.(3)The white blood cells always increase as a stress reaction for aortic dissection.In aortic dissection，the pseudocoel releases pyrogen，which causes fever.Simultaneously，bloody pleural effusions often appear，so aortic dissection should be carefully differentiated from pulmonary infection and tuberculous pleurisy.

(T ranslator：Chen Yanming)

患者男性，51歲，主因“發(fā)作性胸背部疼痛伴呼吸困難5 d”于2008年12月23日急診入院。2008年12月18日解大便時出現(xiàn)右下肢劇烈疼痛并伴有活動障礙，2 h后右下肢疼痛和無力緩解，但出現(xiàn)胸背部劇痛，吸氣時加重，并伴呼吸困難，出汗，無反射痛，無心悸，無惡心嘔吐。4 d后胸背部疼痛逐漸消失，但仍有呼吸困難，遂入承德醫(yī)學院附屬醫(yī)院，急查頭顱CT未見出血灶，血常規(guī)提示白細胞總數(shù)23.23×109/L，中性粒細胞86.5%，心肌酶未見明顯異常，腹部超聲提示雙腎、膀胱、輸尿管未見異常，診斷為上呼吸道感染，治療2 d后背部疼痛減輕，但仍間斷有呼吸困難，為進一步明確診斷入解放軍總醫(yī)院急診，血氣分析：PO251.9 mmHg(1 mmHg=0.133 kPa)，PCO226.5 mmHg ，pH 7.404，HCO-316.2mmol/L，BE-7.2 mmol/L ，血常規(guī)：白細胞總數(shù)14.04×109/L，中性粒細胞77.8%，D-二聚體 8.95 mg/L，生化 ：總膽紅素 53.6 μ mol/L ，直接膽紅素 19.3μ mol/L ，肌酐159.9 μ mol/L ，尿素氮11.24 mmol/L，血鉀 3.20 mmol/L。胸片提示：胸腔積液。腹部超聲提示：(1)肝靜脈增寬；(2)雙側胸腔積液；(3)腹水?？紤]肺栓塞可能性大，遂擬診“胸痛原因待查?”收入解放軍總醫(yī)院老年心血管病研究所。既往有高血壓病史3年，血壓控制欠佳。否認心絞痛病史。無下肢深靜脈血栓病史。體溫：36.7℃，脈搏：105 次/min，呼吸：18次/min，血壓：171/100 mmHg。雙肺呼吸音弱，雙下肺未聞及呼吸音，未聞及干濕性啰音。心率105次/min，律齊，第一心音弱，各瓣膜聽診區(qū)未聞及病理性雜音。腹軟，無壓痛和肌緊張，肝肋下未觸及，移動性濁音陰性。雙下肢無水腫。神經系統(tǒng)查體正常。心電圖(2008-12-23)：竇性心動過速，QⅢ、avF。超聲心動圖：心臟功能正常，心包積液。入院后首先考慮肺栓塞，控制血壓、心率情況下，同時給予低分子肝素鈉60 mg 1次/12 h抗凝。入院后第2天行下肢靜脈超聲和肺灌注掃描，未見異常后停用低分子肝素。后考慮主動脈夾層可能性大，鑒于患者存在腎功能不全，申請了胸部血管磁共振檢查，在等待檢查的過程中(共8 d)，患者行雙側腎動脈超聲、雙側髂動脈超聲檢查未見異常。胸部血管磁共振提示為主動脈夾層，請血管外科會診后，行胸腹主動脈CT血管造影(CT angiography，CTA)，進一步證實主動脈夾層(Stanford B，內膜破口起源于左鎖骨下動脈遠端)。

陳艷明住院醫(yī)師：患者入院后，根據心肌酶、心電圖的變化，首先排除了急性心肌梗死和急性心包炎。診療過程中主要進行肺栓塞和主動脈夾層的鑒別診療。(1)肺栓塞：患者胸痛、呼吸困難明顯，竇性心動過速，血氣(PO251.9 mmHg，PCO2 26.5 mmHg)、D-二聚體升高，肝靜脈增寬、腹腔積液，首先考慮肺栓塞，入院后第一天給予抗凝治療，但該患者無雙下肢靜脈血栓，并且行肺灌注掃描未見明顯異常，不支持該診斷；(2)主動脈夾層：患者既往有高血壓病史，而且控制不佳，胸痛伴右下肢無力，查體腘動脈、足背動脈、脛后動脈搏動弱。主動脈的磁共振和CTA支持該診斷。①但主動脈夾層是否會引起呼吸困難，胸腔、腹腔、心包積液?②血管CTA及血管造影提示右腎動脈受累和雙側髂動脈受累，但腎動脈和髂動脈超聲檢查未見異常，血管超聲在診斷主動脈夾層中的意義?③診療過程中患者腎功能不全(肌酐159.9 μ mol/L)，血壓難控制、頑固的低鉀血癥，發(fā)病時有一側肢體活動障礙，考慮存在繼發(fā)性高血壓，繼發(fā)原因是什么?④患者白細胞升高、血紅蛋白下降的原因是什么?⑤需與主動脈夾層鑒別的其他疾病有哪些?

高磊主管醫(yī)師：(1)主動脈夾層在急性期由于夾層外壁薄，表面可有血液滲出，并且引起胸腔、腹腔、心包積液，但同時出現(xiàn)多漿膜腔積液少見。胸腔積液量大時可有低氧血癥、呼吸困難；(2)經食管超聲心動圖對升主動脈夾層敏感性和特異性高，可以確定內膜裂口的位置，顯示真、假腔的血流狀態(tài)，是否伴發(fā)主動脈關閉不全、心包積液及主動脈弓分支血管的阻塞。但經食管超聲對腹主動脈受累情況的觀察效果不佳。本例當夾層累積腎動脈、髂動脈時，血管超聲檢查未見異常，說明經腹血管超聲檢查對腹主動脈夾層的敏感性低；(3)患者出現(xiàn)右下肢感覺運動喪失的原因：夾層累及患側動脈時，引起缺血性外周神經疾病，可引起感覺、運動喪失；(4)患者有入院后高血壓病史，血壓控制不理想，行腎臟超聲檢查提示為慢性改變，表明在慢性基礎上，腎臟急性缺血后，腎素-血管緊張素-醛固酮系統(tǒng)激活，引起肌酐升高、血壓難控制、低血鉀；(5)主動脈夾層患者常有白細胞升高、血紅蛋白下降，有資料表明與患者預后相關；(6)正常水平的D-二聚體對于除外肺栓塞具有意義。但是該指標特異性差，在急性心肌梗死和主動脈夾層時也可升高。

薛橋主診醫(yī)師：入院后患者的鑒別診斷主要圍繞肺栓塞和主動脈夾層。主動脈夾層時心電圖的改變不特異：如本例為竇性心動過速。胸片只能提示主動脈影增寬，但不能提示為升主動脈夾層還是降主動脈夾層，而且該提示作用敏感性差，如本例患者雖行胸片檢查但未見主動脈增寬。CT和MRI診斷主動脈夾層的準確率高。而且血管CTA對肺栓塞、主動脈夾層鑒別具有重要意義。CT檢測速度快，作一次檢查即可鑒別兩者，并且肌酐159.9 μ mol/L并不是血管CT的檢查禁忌。如果腎功能的惡化因主動脈夾層引起，及早診斷治療可使腎功能及早恢復，并且血管CT對血管外科支架的選擇具有指導意義?；颊呷朐汉笕绻皶r行血管CTA的檢查可以縮短患者確診的時間。

趙玉生主任：主動脈夾層的臨床表現(xiàn)復雜多樣。臨床表現(xiàn)有前胸、后背、腹部的劇烈疼痛，高血壓，臟器缺血表現(xiàn)(脊髓、四肢、腎臟)，夾層破裂(心包積液、腹腔積液、咯血、嘔血)，主動脈瓣關閉不全、聲嘶等。國外較大的醫(yī)療機構也有38%患者首診漏診，28%的患者在尸檢后確診，提示早期診斷主動脈夾層患者并不容易。從該患者的診治過程，除了急性心肌梗死、肺栓塞，主動脈夾層還需要考慮的疾病：(1)患者高血壓病、腎功能不全、發(fā)熱、低氧血癥、胸腹腔心包積液，應與結締組織病相鑒別，并且某些結締組織疾病如系統(tǒng)性紅斑狼瘡也可引起主動脈夾層，病史和實驗室檢查有助于鑒別診斷；(2)高血壓，右側肢體活動障礙應與腦卒中相鑒別。主動脈夾層累及主動脈主要分支如頸動脈、椎動脈時，可同時有腦卒中，二者可并存；(3)主動脈夾層作為應激反應，白細胞總數(shù)可升高，假腔釋放致熱原體溫升高，同時由于胸腔積液存在，應與肺部感染、結核性胸膜炎相鑒別。

(參加討論的醫(yī)師：陳艷明、高 磊、薛 橋、趙玉生)

(陳艷明 整理)

100853北京市，解放軍總醫(yī)院老年心血管病研究所

薛橋，Tel：13126695117，E-mail：chenyanmingabcdo@sin.com.cn

胸痛、呼吸困難男性1例

2010-01-28；

2010-03-19)