心絞痛患者QT離散度與經(jīng)皮腔內(nèi)冠狀動(dòng)脈成形術(shù)的關(guān)系

1、    心絞痛患者QT離散度與經(jīng)皮腔內(nèi)冠狀動(dòng)脈成形術(shù)的關(guān)系        摘要目的：探討經(jīng)皮腔內(nèi)冠狀動(dòng)脈成形術(shù)(PTCA)對(duì)心絞痛患者QT及JT離散度(QTd及JTd)的作用。方法：測(cè)定50例心絞痛患者(心絞痛組)PTCA術(shù)前和術(shù)后的QTd及JTd，并以50例正常冠狀動(dòng)脈者作對(duì)照(對(duì)照組)。結(jié)果：心絞痛組于PTCA后QTd及JTd顯著減小 (P0.01)，而對(duì)照組于冠狀動(dòng)脈造影術(shù)后QTd及JTd與術(shù)前比較，無(wú)明顯改變。與對(duì)照組比較，心絞痛組PTCA前QTd及JTd明顯增大(P

2、0.01)。術(shù)后心絞痛組QTd及JTd值雖高于對(duì)照組，但無(wú)統(tǒng)計(jì)學(xué)意義(P0.05)。結(jié)論：PTCA能使QTd及JTd減小。關(guān)鍵詞QT離散度JT離散度心絞痛經(jīng)皮腔內(nèi)冠狀動(dòng)脈成形術(shù) Relationship between QT dispersion and percutaneous transluminal coronary angioplasty in angina pectoris patientsWANG Wei-qingCHEN Rong-kang（Department of Cardiology,Putuo District Central Hospital,Shanghai 2000

3、62;）SHEN Wei-feng（Department of Cardiology,Ruijing Hospital,Shanghai Second Medical University）AbstractObjective:To study the effects of percutaneous transluminal coronary angioplasty(PTCA) on QT dispersion (QTd) in angina pectoris patients.Method:QTd and JT dispersion (JTd) in 50 patients with angi

4、na pectoris before and after PTCA were measured and compared with those of 50 normal controls. Result:Both QTd and JTd in patients with angina pectoris were significantly reduced after PTCA (P0.01), but these two parameters did not significantly differ in controls before and after angiography. Compa

5、red with the controls, QTd and JTd in angina pectoris patients before PTCA were significantly increased (P0.01),but were no significantly difference after PTCA.Conclusion:PTCA could reduce QTd and JTd of patients with angina pectoris.Key wordsQT dispersionJT dispersionAngina pectorisPercutaneous tra

6、nsluminal coronary angioplastyQT離散度(QTd)及JT離散度(JTd)主要反映心室肌復(fù)極的不均一性1。 QTd或JTd增大，則易產(chǎn)生室性心律失常。經(jīng)皮腔內(nèi)冠狀動(dòng)脈成形術(shù)(PTCA)使冠狀動(dòng)脈狹窄和阻塞減輕，心肌缺血改善。本文目的旨在測(cè)定PTCA對(duì)心絞痛患者QTd和JTd 的作用。1對(duì)象與方法1.1對(duì)象心絞痛組：50例(不穩(wěn)定型心絞痛36例，穩(wěn)定型心絞痛14例)，其中男34例，女16例，年齡3875(63.04±9.07)歲。排除電解質(zhì)紊亂，心房顫動(dòng)和束支傳導(dǎo)阻滯及高血壓，所有患者均未服用影響心肌復(fù)極的藥物。冠狀動(dòng)脈造影顯示至少一支冠狀動(dòng)脈主要分支病變；

7、其中單支病變22例，雙支以上病變28例。對(duì)照組：50例，其中男36例，女14例，年齡3974(60.03±9.39)歲，各例因反復(fù)心前區(qū)疼痛發(fā)作疑診冠心病而行冠狀動(dòng)脈造影。并且排除其他器質(zhì)性疾病。1.2QTd和JTd測(cè)定各例于冠狀動(dòng)脈造影或PTCA前和24 h后記錄標(biāo)準(zhǔn)12導(dǎo)聯(lián)心電(紙速25 mm/s，增益1 mV/10mm)。從每個(gè)QRS波起始部和J點(diǎn)到T波終點(diǎn)測(cè)量QT間期及JT間期， 以T波下降支與基線的交點(diǎn)為準(zhǔn)確定 T波終點(diǎn)。如有U波，則采用T波與U波之間的切跡為準(zhǔn)。各例測(cè)量8個(gè)以上導(dǎo)聯(lián)，每個(gè)導(dǎo)聯(lián)均連續(xù)測(cè)量3個(gè)QT間期和JT間期，取其平均值。并以最大QT和JT間期與最小QT和J

8、T間期之差計(jì)算QTd及JTd。1.3統(tǒng)計(jì)學(xué)處理數(shù)據(jù)以±s表示，采用t檢驗(yàn)，以P0.05為有顯著性差異。2結(jié)果心絞痛組22例行單支血管病變PTCA，其中：左前降支14例，左回旋支2例，右冠狀動(dòng)脈6例。雙支或以上血管病變28例行PTCA，左前降支22支，回旋支13支，右冠狀動(dòng)脈22支。兩組PTCA術(shù)前、后QTd、JTd比較見表1。表1兩組PTCA術(shù)前、術(shù)后QTd和JTd比較ms，±s組別QTdJTd術(shù)前術(shù)后術(shù)前術(shù)后心絞痛組73.04±9.492)53.46±8.871)74.14±7.972)54.01±8.211)對(duì)照組45.33

9、77;9.6244.62±8.6546.52±8.9645.38±8.07與術(shù)前比較，1)P0.01；與對(duì)照組比較，2)P0.01 3討論QT間期是心室肌除極和復(fù)極的總時(shí)間，而JT間期消除了心室除極時(shí)限的影響，更準(zhǔn)確反映復(fù)極時(shí)間。 QTd和JTd代表心室肌復(fù)極不同步性和電不穩(wěn)定性的程度2。心肌內(nèi)電變化的不均勻分布，局部心肌細(xì)胞存在后除極，局部室壁運(yùn)動(dòng)異常，心肌不對(duì)稱肥厚以及局部自主神經(jīng)張力改變等均可導(dǎo)致局部電位變化和傳導(dǎo)變化，引起 QTd和JTd改變3。PTCA使冠狀動(dòng)脈血管再通，心肌血供改善。但PTCA成功后對(duì)QTd和JTd的影響，報(bào)道不多。冠心病心肌缺血時(shí)，由

10、于缺血部位跨膜動(dòng)作電位時(shí)限延長(zhǎng)及局限性傳導(dǎo)延遲，使心肌細(xì)胞的除極與復(fù)極過(guò)程延遲，加上心肌組織間復(fù)極不一致，心室不應(yīng)期離散度增加導(dǎo)致QTd和JTd延長(zhǎng)。本文結(jié)果表明，心絞痛組PTCA術(shù)前的QTd和JTd顯著高于對(duì)照組, PTCA術(shù)后的QTd和JTd較術(shù)前顯著縮短。這些提示,成功的PTCA使術(shù)后心肌灌注改善,缺血逆轉(zhuǎn),導(dǎo)致心室不應(yīng)期離散度和QTd及JTd減小。因此,PTCA能改善心肌缺血，對(duì)防止心律失常發(fā)生及改善臨床預(yù)后具有益作用4。汪蔚青(上海市普陀區(qū)中心醫(yī)院心臟科 上海,200062)陳榮康(上海市普陀區(qū)中心醫(yī)院心臟科 上海,200062)沈衛(wèi)峰(上海第二醫(yī)科大學(xué)附屬瑞金醫(yī)院心臟科)參考文獻(xiàn)1，Statters D J,Malik M,Ward D E,et al. QT dispersion:Problems of methodology and clinical significance. J Cardiovasc Electrophysiol，1994，5:6726772，Pye M,Quinn A C,Cobbe S M.QT interal dispersion:A noninvasive marker of susceptibility to arrhythmia in patients