원저 Korean Circulation J 2003;33(2):97-103 급성전벽심근경색환자에서재관류요법후 ST 분절상승형태에따른좌심실기능의예측 원광대학교의과대학내과학교실, 1 전남대학교의과대학전남대학교병원심장센터 2 김남호 1 정진원 1 오석규 1 안영근 2 정명호 2 조정관 2 박종춘 2 강정채 2 Value of ST-segment Elevation Pattern in Predicting Left Ventricular Function in Patients with Reperfused Acute Anterior Myocardial Infarction Nam-Ho Kim, MD 1, Jin-Won Jeong, MD 1, Seok Kyu Oh, MD 1, Young Keun Ahn, MD 2, Myung Ho Jeong, MD 2, Jeong Gwan Cho, MD 2, Jong Chun Park, MD 2 and Jung Chaee Kang, MD 2 1 Department of Internal Medicine, Wonkwang University School of Medicine, Iksan, 2 The Heart Center, Chonnam National University Hospital, Gwangju, Korea ABSTRACT Background and Objectives:The implication of the shape of ST elevation in the acute phase of myocardial infarction (MI) remains unclear. Subjects and Methods:We examined the relationship between the shape of the ST elevation and infarct size in 60 patients having had a first acute anterior myocardial infarction with reperfusion within 12 hours from the onset of symptoms. A 12-lead electrocardiogram was recorded immediately before, and on the 1st day following reperfusion. Results:The shapes of the ST elevation in lead V 3 of the electrocardiogram on the 1st day following reperfusion were classified into 3 types:concave, straight and convex types, with 11, 20 and 29 patients in each group, respectively. The left ventricular ejection fraction was measured by echocardiography at the time of discharge (7 days after the MI), and the concave, straight and convex types were 57.0, 52.5 and 47.7% (p<0.05), respectively. However, there were no significant differences in the mean values of peak troponin I and CK-MB among the three groups. Conclusion:In patients with reperfused acute anterior MI, the left ventricular function was excellent in patients with the concave type, but relatively poor in those with the convex type ST elevation on the first day following reperfusion. (Korean Circulation J 2003;33(2):97-103) KEY WORDS:Myocardial infarction;ventricular function, left;electrocardiography. 서론 급성심근경색에서혈전용해요법은중요한치료방법이다. 심근경색과관련한사망률의감소는혈전용해요 법에의한관상동맥의재관류가큰역할을하였고, 1)2) 경색의크기는예후와큰연관성이있다. 3) 그래서경색의크기를빠르게그러면서도비교적간편하게예측하고자하는노력들이있어왔다. 심전도상 논문접수일 :2002 년 08 월 14 일수정논문접수일 :2002 년 10 월 1 일심사완료일 :2002 년 11 월 19 일교신저자 : 정진원, 501-757 전북익산시신용동 344-2 원광대학교의과대학내과학교실전화 :(063) 850-1070 전송 :(063) 852-8480 E-mail:jjwcar@wonkwang.ac.kr 97
혈전용해요법을하기전과후의 Selvester QRS score 는경색의정도를잘반영하는것으로알려졌으며, 4)5) ST 분절이상승된유도의수와전흉부에서 ST 분절이상승된정도의합으로경색의크기및좌심실의기능을예측하고자하는시도들이이루어져왔다. 6)7) 하지만, 대부분의연구들이 QRS 파, ST 분절의상승정도및상승된유도수, 혈전용해요법후 ST 분절의상승이정상화되는시간, 그리고 ST 분절과 T파의형태를통한연구들이었고, 8-10) 심근경색의급성기에 ST 분절의상승된형태를통한경색의크기및좌심실기능의예측은거의시도되지않았다. 11)12) 그래서본저자들은급성전벽심근경색환자에서 ST 분절의상승형태를통하여퇴원당시좌심실기능을예측할수있는지를알아보고자하였다. 대상및방법 대상환자관찰대상은 1998 년 1월부터 1999 년 7월까지전남대학교병원, 2002년 1월부터 5월까지원광대학병원에내원한첫번째급성전벽심근경색환자 221 명중 V 3 A B C Fig. 1. Schema of the shape of ST-segment elevation. A:concave type, B:straight type, C:convex type. 유도에서 3 mm 이상의 ST 분절의상승과양성 T파가관찰되고, 흉통발생한지 12시간내에재관류요법을시행하였던환자 60명 ( 남 47, 여 13, 59±10 세 ) 을대상으로하였다. 정의급성전벽심근경색은 30분이상지속되는흉통, 인접한 2개이상의전흉부유도에서 ST분절이 0.1 mv이상의상승, 그리고혈청심근효소의증가로정의하였다. 심전도분석재관류요법후 1일째표준 12유도심전도를분석하였다. 등전위선은 TP 분절을기준으로하여 ST 분절의상승정도는 J점에서측정하였고, 전흉부유도에서 ST 분절의상승정도의합을구하였다. 또한비정상 Q파가기록된전흉부유도수및 Q파의크기의합을측정하였다. ST 분절의상승의형태는 V 3 유도에서 3가지형태 ( 오목형, 직선형, 볼록형 ) 로나누어후향적인분석을하였다 (Fig. 1, 2). 관상동맥조영술관상동맥조영술은 Judkins씨방법으로좌관상동맥은전후면, 우전경사면 30, 좌전경사면 45, 좌측면에서시행하였고, 우관상동맥은우전경사면 45, 좌전경사면 45 에서시행하였는데필요에따라또다른투사면에서추가로시행하였다. 관상동맥조영술상좌전하행지동맥에내경 50% 이상의유의한협착이있는경우중재시술을시행하였다. A B C Fig. 2. Representative electrocardiograms of 3 types of ST elevation shape. Concave type, culprit lesion, mid- LAD. Time from symptom onset to reperfusion, 5 hours. LVEF 70% at discharge day (A). Straight type, culprit lesion, mid-lad. Time from symptom onset to reperfusion, 6 hours (B). LVEF 55% at discharge day. Convex type, culprit lesion, mid-lad. Time from symptom onset to reperfusion, 4.8 hours. LVEF 48% at discharge day (C). LVEF:left ventricular ejection fraction. 98 Korean Circulation J 2003;33(2):97-103
좌심실기능의평가대상환자들은 Sequoia C 256(Acuson, USA) 의 2.5 MHz 탐촉자를이용하여내원당시와재관류요법후 7일째 Simpson s method 에의하여좌심실의기능을측정하였다. 통계모든자료의값은평균 ± 표준편차로표시하였으며, 통계분석은 SPSS 7.5 프로그램을이용하여세군간의연속변수에대한통계학적검정은일원배치분산분석 (one-way ANOVA) 를이용하였고 p값이 0.05 이하인경우에사후분석은 Tukey 다중 t 검정을실시하였다. 범주형변수 (categoric variables) 는 chi-square test 를시행하였다. p값이 0.05 이하를통계적으로의의가있다고보았다. 차이가없었다 (Table 2). 재관류직전의심전도와관계재관류직전의 ST 분절의상승형태는 Ⅰ군에서오목형 9명, 직선형 2명, Ⅱ군에서오목형 17명, 직선형 2명, 볼록형 1명, Ⅲ군에서오목형 27명, 직선형 2명으로세군간에차이가없었다. 재관류직전의 ST 분절이상승된유도수는세군간에차이가없었다. ST 분절의상승된정도의합은 Ⅰ군에서다른두군에비하여낮은경향을보였으나통계학적인의의는없었다. 재관류요법전과후의 ST 분절상승의회복정도또한세군간에차이가없었다. 재관류직전의 Q파의유도수는 Ⅰ군 0.7±1.3, Ⅱ군 1.6±1.8, Ⅲ군 2.4±2.0 으로 Ⅰ군에서 Ⅲ군에비해유의하게적었고 (p=0.03), Q파의전압의크기는각각 1.64±2.15 mv, 3.31±2.44 결 대상환자의임상적특성대상환자들은혈전용해요법후 1일째심전도의 V 3 유도에서 ST 분절상승형태에따라세군으로나누어분석하였다. 11명은오목형 ST 분절상승 (Ⅰ군), 20명은직선형 ST 분절상승 (Ⅱ군), 29명은볼록형 ST 분절상승 (Ⅲ군) 을나타내었다. 세군간의나이, 성별, 내원당시수축기혈압및이완기혈압, 내원당시맥박수, 재관류요법까지의시간, 위험인자등은유의한차이는없었다 (Table 1). 모든환자는내원후평균 3±2 일에관상동맥조영술을시행하였고, 관상동맥조영술상병변위치, 병변의형태, 혈류의정도는세군간에유의한 과 Table 1. Baseline characteristics of patients Table 2. Angiographic findings of patients Culprit lesion (proximal/middle) Group Ⅰ (n=11) Group Ⅱ (n=20) Group I (n=11) Group Ⅱ (n=20) Group Ⅲ (n=29) Age (y) 061±11 060±10 057±10 Men (%) 10 (90.9) 13 (65.0) 24 (82.8) Systolic blood pressure on admission (mmhg) 134±28 147±21 141±25 Diastolic blood pressure on admission (mmhg) 089±18 091±15 089±18 Heart rate on admission (beats/min) 072±13 078±13 076±12 Time to reperfusion (h) 03.7±1.7 06.3±3.1 05.4±2.9 Risk factors (%) Hypertension 03 (27.3) 08 (40.0) 14 (48.3) Diabetes mellitus 03 (27.3) 04 (20.0) 07 (24.1) Dyslipidemia 03 (27.3) 07 (35.0) 12 (41.4) Smoking 05 (45.5) 13 (65.0) 15 (51.7) Values are expressed as mean±standard deviation or number (percent) Group Ⅲ (n=29) 4/7 10/9 18/10 TIMI 0 0 03 03 1 0 01 02 2 8 11 16 3 3 05 08 Lesion type A 0 00 00 B1 6 07 16 B2 3 09 08 C 2 04 05 Values are expressed as number 99
Table 3. Electrocardiographic findings before reperfusion Group Ⅰ (n=11) Group Ⅱ (n=20) Group Ⅲ (n=29) Sum of ST elevation (mv) 1.08±0.670 1.20±0.85 1.61±1.35 Number of elevated ST-segment 4.00±1.600 4.00±0.70 4.30±1.30 Sum of Q amplitude (mv) 1.64±2,15* 3.31±2.44 4.20±2.73 Number of pathologic Q 0.70±1.3*0 1.60±1.80 2.40±2.00 Values are expressed as mean±standard deviation. *:p<0.05 vs group Ⅲ Table 4. Mean values of peak cardiac enzyme and left ventricular function Group Ⅰ (n=11) Group Ⅱ (n=20) Group Ⅲ (n=29) Myoglobin (ng/ml) 286.0±205 362.0±174 394.0±190 CK-MB (U/L) 146.0±145 247.0±165 248.0±171 Troponin I (ng/ml) 055.0±046 096.0±055 106.0±056 LVEF at admission (%) 050.8±007.0 048.3±011.5 045.0±009.7 LVEF at follow-up (%) 057.0±008.1* 052.5±011.1 047.7±010.1 ΔLVEF (%) 006.2±005.0 004.3±004.9 003.0±012.1 Values are expressed as mean±standard deviation. *:p<.05 vs group Ⅲ. CK-MB:MB isoenzyme of creatine kinase, LVEF:left ventricular ejection fraction, ΔLVEF:difference of LVEF between follow-up and admission 군에서가장높은호전의정도를보였으나통계학적으로유의하지는않았다 (Table 4). 성공적인재관류 (TIMI Ⅱ-Ⅲ) 가이루어진환자군과비교성공적인재관류가이루어진환자는오목형 11명, 직선형 16명, 볼록형 24명이었다. 각각의좌심실구혈률은 57.0±8.1%, 53.2±11.1%, 49.7±10.9% 이었으며, 전체환자군과비교하였을때통계학적으로유의한차이는없었다 (Fig. 3). Fig. 3. Comparison of left ventricular ejection fraction between all included patients and successful thrombolytic patients. *:p=non-specific. 고 찰 mv, 4.20±2.73 mv로 Ⅰ군에서 Ⅲ군에비하여유의하게낮았다 (p=0.02)(table 3). 심근경색의크기와좌심실기능혈중 CK-MB, troponin Ⅰ는 Ⅰ군에서 Ⅱ군과 Ⅲ 군에비하여낮은경향을보였으나통계학적으로유의하지는않았다. 내원당시좌심실구혈률은 Ⅰ군 50.8± 7.0%, Ⅱ군 48.3±11.5%, Ⅲ군 45.0±9.7% 로세군간에유의한차이는없었으며, 혈전용해요법후 7일째좌심실구혈률은 Ⅰ군 57.0±8.1%, Ⅱ군 52.5±11.1%, Ⅲ군 47.7±10.1% 로 Ⅰ군에서 Ⅲ군에비해유의하게좋았다 (p=0.02). 좌심실기능의호전의정도는 Ⅰ군 6.2±5.0%, Ⅱ군 4.3±4.9%, Ⅲ군 3.0±12.1% 로 Ⅰ 급성심근경색에서경색의크기정도가단기와장기예후에중요한역할을한다. 3) 그래서간편하면서도비침습적이고경제적인표준형 12 유도심전도로심근경색의정도를예측하고자하는많은연구가다양한형태로진행되어왔다. 4)13-15) 심전도상 QRS score 와 ST 분절을이용한방법들이대표적이다. 하지만, 보고자에따라서는서로상반된결과를발표하기도하여아직은경색의크기예측에있어서심전도의역할은아직명확하지않으나, 재관류요법전의 Selvester 32-point QRS scoring system 은보존적인치료를한환자에서예후를예측하는데그유용성은인정된다. 16) 그러나, 혈전용해요법을실시한경우에서는심전도상 Q파가나타나는경색부위에서생존심근의존재로그유용성이의 100 Korean Circulation J 2003;33(2):97-103
문시되기도한다. 17) Juergens 등 5) 은심근경색 7일째 32-point QRS score 가혈전용해요법후경색정도를평가하는지표가될수있음을보고하였고, Birnbaum 등 18) 은혈전용해요법을받은심근경색환자의내원당시심전도에서 QRS 군의끝부분의왜곡현상이사망률과관련이있다는보고를하였다. 심근경색의급성기에 ST 분절의상승은심근허혈의심한정도를반영한다. 8) ST 분절을이용한경색의크기및심실기능의예측은상승된 ST 분절의수와상승된정도의합이주로이용되어졌다. 7)8) Mauri 등 19) 은 GISSI-1 연구에포함되었던환자들을대상으로내원당시 ST 분절이상승된유도수에따라 4군으로분류하여 10년후의사망률을분석하였는데 ST 분절의상승유도수가작은군에서장기예후가좋음을보고하여심전도가장기예후의예측인자로서사용할수있음을보고하였다. 최근에는 ST 분절의형태를이용하여경색의크기및심실의기능을예측하려고하는시도가이루어지고있다. 11)12) Adler 등 12) 은 ST 분절의상승없이음성 T파만있는경우가 ST 분절의상승과음성 T파가있는경우와 ST 분절의상승과양성 T파가있는경우보다관류결손의정도가적고, 관류결손이있는분절수또한적고, 심실구혈률이높음을보고하여재관류요법 3~10 일후의 ST-T 형태로경색의크기및좌심실의수축기기능을예측할수있음을보고하였다. 저자들은본연구에서혈전용해요법후 1일째심전도에서 ST 분절의상승형태를 V 3 유도에서 3가지 ( 오목형, 직선형, 볼록형 ) 형태로나누어각각의형태에따른경색의정도를후향적인분석을통하여비교하였다. Ben-gal 등 20) 은급성전벽심근경색에서 V 1 유도에대한의문점을제시하였는데, V 1 유도는좌전하행지의 septal branch 와우관상동맥의 conal branch 에의해같이혈류를공급받는경우도있어전벽경색을잘반영할수없다는점이다. 그래서본저자들은 V 3 유도에서 ST 분절을분석하였다. 본연구에서재관류 1일째심전도의 V 3 유도에서오목형 ST 분절상승은재관류요법전에서적은병적인 Q파의수, 낮은병적인 Q파의전압크기의합, 그리고퇴원당시의보다보존된좌심실기능과연관성이있었다. 볼록형 ST 분절상승은재관류요법전많은병적인 Q파의수, 높은병적인 Q파의전압크기의합, 그리고퇴원당시낮은좌심실기능과연관성이있었다. 하지만, 혈중 troponin Ⅰ와 CK-MB 는오목형 ST 분절상승에서낮은경향을보였으나통계학적으로유의하지는않았다. 급성심근경색에서 ST 분절상승형태의차이가발생하는기전에대하여서는아직명확하지않다. 심근허혈초기에막성활동전위가현저한변화를일으키는데, 허혈은활동전위기간을짧게하며, 전압, 상승속도, 안정전위를감소시킨다. 21-23) 활동전위파의변화는활동전위곡선의 2기와 3기를변화시키고, 이러한변화는 ST 분절의상승형태를변화시키는데이는심근손상의정도를반영한다. ST 분절형태중오목형 ST 분절상승은정상적인 ST 분절의형태와유사하므로심근손상정도가덜할것으로생각되며, 이러한심근손상정도는심실의기능에영향을주어오목형 ST 분절상승에서심실기능이가장잘보존될것으로기대한다. 본연구에서도좌심실의수축기기능은오목형에서볼록형에비하여좀더보존된것을확인할수있었다. 본연구의제한점으로는첫째, 소규모의환자에서이루어진후향적인연구라는점이다. 향후많은환자를대상으로다기관으로전향적인연구가진행되어야할것이다. 둘째는경색의정도를심근효소로만평가하였는데이를보완할수있어야할것이다. 핵의학검사를보조적인방법으로추가한다면경색의정도를정량화하는데많은도움을얻을수있을것으로생각된다. 셋째는좌심실의기능평가를비교적조기인 7일째실시하였는데, 생존심근의존재로인한심실의기능변화가있을수있으므로장기적인추적검사가필요할것이다. 하지만, 이와같은제한점에도불구하고급성전벽경색을갖는환자에서재관류요법후 1일째심전도상 V 3 유도에서 ST 분절의형태는퇴원시환자의좌심실의기능을평가할수있는하나의지표로사용할수있을것으로생각한다. 요약 배경및목적 : 급성전벽심근경색환자에서혈전용해요법후 1일째 V 3 유도에서 ST분절상승형태를분석하여퇴원전좌심실기능을예측할수있는지알아보고자하였다. 방법 : 급성전벽심근경색으로내원한 221 명중 V 3 유도에서 3 mm 이상의 ST 분절상승과양성 T파가관찰되 101
고, 흉통이발생한지 12시간이내에혈전용해요법이이루어진 60명 ( 남 47, 여 13, 59±10 세 ) 을대상으로하였다. 결과 : 혈전용해요법전의 ST 분절증가합, Troponin Ⅰ 값, 그리고 CK-MB 값은오목형에서직선형과볼록형에비교하여낮은경향을보였으며, 흉통발생후재관류요법까지의시간은오목형보다는직선형과볼록형에서높은경향을보였다. 재관류요법전의 Q파유도수와 Q파의전압크기의합은오목형에서볼록형에비하여유의하게낮았다 (p<0.05). 내원당시좌심실구혈률은세군간에유의한차이는없었느나, 퇴원당시좌심실구혈률은오목형에서볼록형에비해좋았다 (p=0.02). 결론 : 급성전벽경색을갖는환자에서혈전용해요법후 1 일째심전도상 V 3 유도에서 ST 분절의형태는퇴원시환자의좌심실의기능을평가할수있는하나의지표로사용할수있을것이다. 중심단어 : 심근경색 ; 좌심실기능 ; 심전도. 이논문은 2002 년도원광대학교의교비지원에의해서수행됨. REFERENCES 1) Gruppo Italiano per lo Studio della Streptochinasi nell' Infarto Miocardico (GISSI). Effectiveness of intravenous thrombolytic treatment in acute myocardial infarction. Lancet 1986;1:397-402. 2) Second International Study of Infarct Survival(ISIS-2) Collaborative Group. Randomized trial of intravenous streptokinase, oral aspirin, both, or neither among 17,187 cases of suspected acute myocardial infarction. J Am Coll Cardiol 1988;12(Suppl A):3A-13A. 3) Geltman EM. Infarct size as a determinant of acute and longterm prognosis. Cardiol Clin 1984;2:95-103. 4) Selvester RH, Wagner GS, Hindman NB. The selvester QRS scoring system for estimating myocardial infarct size: the development and application of the system. Arch Intern Med 1985;145:1877-81. 5) Juergens CP, Fernandes C, Hasche ET, Meikle S, Bautovich G, Currie CA, Freedman SB, Jeremy RW. Electrocardiographic measurement of infarct size after thrombolytic therapy. J Am Coll Cardiol 1996;27:617-24. 6) Aldrich HR, Wagner NB, Boswick J, Corsa AT, Jones MG, Grande P, Lee KL, Wagner GS. Use of initial ST-segment deviation for prediction of final electrocardiographic size of acute myocardial infarcts. Am J Cardiol 1988;61:749-53. 7) Clemmensen P, Grande P, Aldrich HR, Wagner GS. Evaluation of formulas for estimating the final size of acute myocardial infarcts from quantitative ST-segment elevation on the initial standard 12-lead ECG. J Electrocardiol 1991; 24:77-83. 8) Daniell HB. Studies on the relationship between ST-segment elevations and extent of infarction following coronary artery occlusion in dogs. Res Commun Chem Pathol Pharmacol 1979;23:333-40. 9) Jain A, Gettes LS. Patterns of ST-segment change during acute no-flow myocardial ischemia produced by balloon occlusion during angioplasty of the left anterior descending coronary artery. Am J Cardiol 1991;67:305-7. 10) Purcell IF, Newall N, Farrer M. Change in ST segment elevation 60 minutes after thrombolytic initiation predicts clinical outcome as accurately as later electrocardiographic changes. Heart 1997;78:465-71. 11) Kosuge M, Kimura K, Ishikawa T, Kuji N, Tochikubo O, Sugiyama M, Ishii M. Value of ST-segment elevation pattern in predicting infarct size and left ventricular function at discharge in patients with reperfused acute anterior myocardial infarction. Am Heart J 1999;137:522-7. 12) Adler Y, Zafrir N, Ben-Gal T, Lulu OB, Maynard C, Sclarovsky S, Balicer R, Mager A, Strasberg B, Solodky A, Wagner GS, Birnbaum Y. Relation between evolutionary ST segment and T-wave direction and electrocardiographic prediction of myocardial infarct size and left ventricular function among patients with anterior wall Q-wave acute myocardial infarction who received reperfusion therapy. Am J Cardiol 2000;85:927-33. 13) Rautaharju PM, Warren JW, Jain U, Wolf HK, Nielsen CL. Cardiac infarction injury score: an electrocardiographic coding scheme for ischemic heart disease. Circulation 1981; 64:249-56. 14) Askenazi J, Maroko PR, Lesch M, Braunwald E. Usefulness of ST segment elevations as predictors of electrocardiographic signs of necrosis in patients with acute myocardial infarction. Br Heart J 1977;39:764-70. 15) Hindman NB, Schocken DD, Widmann M, Anderson WD, White RD, Leggett S, Ideker RE, Hinohara T, Selvester RH, Wagner GS. Evaluation of a QRS scoring system for estimating myocardial infarct size: specificity and method of application of the complete system. Am J Cardiol 1985;55: 1485-90. 16) Holmvang L, Lyck F, Clemmensen P, Behar V, Maynard C, Grande P, Wagner GS. Serial prognostic capabilities of electrocardiographic indices of infarcted and hibernating myocardium in predicting short- and long-term outcome following coronary artery bypass surgery. Cardiology 1997; 88:333-9. 17) Brunken R, Tillisch J, Schwaiger M, Child JS, Marshall R, Mandelkern M, Phelps ME, Schelbert HR. Regional perfusion, glucose metabolism, and wall motion in patients with chronic electrocardiographic Q wave infarctions: evidence for persistence of viable tissue in some infarct regions by positron emission tomography. Circulation 1986;73:951-63. 18) Birnbaum Y, Criger DA, Wagner GS, Strasberg B, Mager A, Gates K, Granger CB, Ross AM, Barbash GI. Prediction of the extent and severity of left ventricular dysfunction in anterior acute myocardial infarction by the admission electrocardiogram. Am Heart J 2001;141:915-24. 19) Mauri F, Franzosi MG, Maggioni AP, Santoro E, Santoro L. Clinical value of 12-lead electrocardiography to predict the 102 Korean Circulation J 2003;33(2):97-103
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