Nucl Med Mol Imaging Vol. 40,. 3, Jun 2006 당뇨병환자에서심근관류 SPECT 을이용한관동맥질환의진단 : 위험인자분석 경북대학교의과대학핵의학교실서지형 * 강성민 배진호 정신영 이상우 유정수 안병철 이재태 Diagnosis of Coronary Artery Disease using Myocardial Perfusion SPECT in Patients with Diabetes Mellitus: Analysis of Risk Factors Ji-Hyoung Seo, M.D., Seong-Min Kang, M.D., Jin-Ho Bae, M.D., Shin-Young Jeong, M.D., Sang Woo Lee, M.D., Jeong-Soo Yoo, Ph.D., Byeong-Cheol Ahn, M.D. and Jaetae Lee, M.D. Department of Nuclear Medicine, School of Medicine, Kyungpook National University, Daegu, Korea Purpose: Diabetes mellitus (DM) is a critical disease with higher rates of cardiovascular morbidity and mortality due to myocardial ischemia and infarction. There is growing interest in how to determine high-risk patients who are candidates for screening testing. This study was performed to evaluate the incidence of coronary artery disease (CAD) in diabetic patients detected by Tc-99m MIBI myocardial perfusion SPECT (MPS) and to assess risk factors of CAD and cardiac hard events. Subjects and Methods: 203 diabetic patients (64 male, mean age 64.1 ±9.0 years) who underwent MPS were included between Jan 2000 and July 2004. Cardiac death and nonfatal myocardial infarction (MI) were considered as hard events, and coronary angioplasty and bypass surgery >60 days after testing were considered as soft events. The mean follow-up period was 36±18 months. Patients underwent exercise (n=6) or adenosine stress (n=197) myocardial perfusion SPECT. Results: Perfusion defects on MPS were detected in 28.6% (58/203) of the patients. There was no cardiac death but 11 hard events were observed. The annual cardiac hard event rate was 1.1%. In univariate analysis of clinical factors, typical anginal pain, peripheral vascular disease, peripheral polyneuropathy, and resting ECG abnormality were significantly associated with the ocurrence of hard events. Anginal pain, peripheral vascular disease, and resting ECG abnormality remained independent predictors of nonfatal MIs with multivariate analysis. Abnormal SPECT results were significantly associated with high prevalence of hard events but not independent predictors on uni- and multivariate analyses. Conclusion: Patients who were male, had longer diabetes duration (especially over 20 years), peripheral vascular disease, peripheral polyneuropathy, or resting ECG abnormality had higher incidence of CAD. Among clinical factors in diabetic patients, typical angina, peripheral vascular disease, peripheral polyneuropathy, and resting ECG abnormality were strong predictors of hard events. (Nucl Med Mol Imaging 2006;40(3):155-162) Key Words: coronary artery disease, diabetes mellitus, cardiac event, myocardial perfusion SPECT 서 당뇨병환자는관동맥질환의이환률과그로인한사망률이높다. 다양한보고가있지만당뇨병에서관동맥질환이발생할빈도는 2-4배더높고, 1) 75% 의당뇨병환자들은관동 Received: 2006. 3. 28. Accepted: 2006. 4. 26. Address for reprints: Jaetae Lee, M.D., Department of Nuclear Medicine, Kyungpook National University Hospital, #50 Samduck 2-ga, Jung-gu, Daegu 700-721, Korea Tel: 82-53-420-5583, Fax: 82-53-422-0864 E-mail: jaetae@knu.ac.kr 본연구는산업자원부지방기술혁신사업 (RTI04-01-01) 지원으로수행되었음. 론 맥질환으로사망한다고한다. 2) 특히당뇨병환자에서는무통성심근경색과심근허혈의빈도가높아조기발견이어렵고진단될당시에심각한수준의관동맥질환을가지고있는경우가많다. 3,4) 1998년미국당뇨병협회 (ADA) 의일치된지침서에서는두개또는그이상의관동맥질환의위험인자를가지고있는당뇨병환자의경우심장부하검사를권하고있다. 5) 그러나관동맥질환의증상이없는환자에서심장부하검사로심근허혈이진단되는빈도는만족스러울만큼높지는않고, 전통적인심장위험인자들만으로관상동맥질환을정확하게예측할수있는것은아니었으므로최근에는고위험군의환자들을대상으로진단검사를선별하여시행하여야한다는것에대한관심이모아지고있다. 155
Ji-Hyoung Seo, et al. Diagnosis of Coronary Artery Disease using Myocardial Perfusion SPECT in Patients with Diabetes Mellitus: Analysis of Risk Factors Table 1. Characteristics of Diabetes Mellitus Patients Who Underwent Myocardial Perfusion SPECT Male/female 64 (31.5)/139 (68.5) Age (years) 64.1±9.0 Clinical variables Diabetes duration (years) HbA1c (%) Random blood glucose (mg/dl) 15.4±8.0 8.7±2.2 236.7±109.5 Treatment Oral hypoglycemic agent (OHA) 85 (41.9) Oral hypoglycemic agent + insulin118 (58.1) Drinking Heavy Social or ne Smoking Symptoms Symptomatic Angina Dyspnea Asymptomatic Hypertension Resting ECG rmal Abnormal DM complications Dyslipidemia Retinopathy Peripheral vascular disease Albuminuria Peripheral polyneuropathy 17 (8.4) 186 (91.6) 65 (32.0) 138 (68.0) 82 (40.4) 39 (19.2) 43 (21.2) 121 (59.6) 104 (51.2) 99 (48.8) 171 (84.2) 32(15.8) 111 (54.7) 115 (56.7) 12 (5.9) 131 (64.5) 130 (64.0) *Data are mean±sd or number of patients (%). *Systemic hypertension was defined by history of systolic blood pressure 140 mm Hg or diastolic blood pressure 90 mm Hg, and dyslipidemia by total cholesterol 240 mg/dl, LDL 160 mg/dl, or HDL <35 mg/dl. Retinopathy (i.e., background, preproliferative, proliferative, macular edema, or history of laser treatment) was assessed from ophthalmological exam. Peripheral vascular disease was defined as the presence of symptoms of claudication or history of peripheral vascular surgery, and albuminuria as proteinuria of over 30mg measured in 24 hour urine collection. The presence of significant ST-T abnormality or Q wave was considered as resting ECG abnormality. Tc-99m sestamibi(mibi) 는심근관류의평가에사용되는방사능의약품으로서관동맥질환을진단하는데높은예민도와특이도를보인다. 6-8) 부하심근관류 SPECT 에서나타난관류이상의범위와중증도는환자의예후와도직접적인관련이있으며심근관류 SPECT 에서정상적인심근관류를보인환자의경우에는연간 1% 미만의낮은심장사건발생률을나타낸다. 9,10) 그러므로 Tc-99m MIBI 심근관류 SPECT 은관동맥질환이의심되거나이미이환되어있는당뇨병환자모두에게서심근관류의평가에유용할것으로추측할수 Table 2. Reasons of Referral for Myocardial Perfusion SPECT in Diabetic Patients Symptomatic 59 (29.0) Asymptomatic Evaluation of cardiovascular complications Pre-operative evaluation Patients requested *Data are number of patients (%). 144 (71.0) 97 (47.8) 35 (17.2) 12 (5.9) 있다. 본연구는 Tc-99m MIBI 심근관류 SPECT 을이용하여당뇨병환자에서관동맥질환의발생빈도를알아보고, 관동맥질환발생및심장사건의발생과연관된위험인자를규명하고자하였다. 1. 연구대상 대상및방법 2000년 1월부터 2004년 7월사이에심근관류 SPECT 검사가의뢰된당뇨병환자들중심근경색, 경피적관동맥성형술, 관동맥우회수술혹은심장판막질환의기왕력이없는 203명의환자를대상으로하였다. 검사를의뢰한사유로는흉통이나호흡곤란등의증상이있어시행한경우가 59명 (29%) 이었으며, 증상은없으나당뇨합병증의진단이나수술전심장상태를평가하기위해서, 혹은환자자신이검사를원해서시행한경우가 144명 (71%) 이었다.(Table 2) 심장사망및비치명적심근경색을중증심장사건 (hard event) 으로정의하였고, 검사후 60일이후에경피적관동맥성형술이나관동맥우회수술을시행한정도로심근허혈이악화된경우를경증심장사건 (soft event) 으로정의하였다. 2. 검사방법 환자들은운동부하 (n=6) 혹은아데노신 (n=197) 부하심근관류 SPECT 을시행하였으며환자의사정과검사실의편의에따라 1일혹은 2일검사법을시행하였다. 1일검사법은 15 mci와 30 mci, 2일검사법은안정시와부하시에각각 20 mci Tc-99m MIBI를정맥주사하였다. 3. 운동부하검사 환자들은 Bruce 방법에의한증상제한적답차운동검사를시행하였다. 거의최대의운동량에도달하였을때 Tc-99m MIBI를주사하였고주사후 1분간더최대강도로의운동을지속하였다. 심전도상 J point의 80 ms 후에 ST분절의하강 156
서지형외. 당뇨병환자에서심근관류 SPECT 을이용한관동맥질환의진단 : 위험인자분석 Table 3. Results of Exercise ECG tests Positive Negative n diagnostic Suboptimal heart rate 1 Total 6 *Data are number of patients. 이 1 mm 이상나타난경우를 양성, 안정상태의심전도상좌각차단, 1 mm 이상의 ST 분절의하강이있는경우를 진단에부적절함, 최대예측심박수의 85% 이상도달하였음에도심전도상 ST분절의하강이나타나지않는경우를 음성 으로판정하였다. SPECT 영상의획득은방사능의약품주사후 30분에서 60분사이에시작하였다. 4. 아데노신부하검사 환자들은검사 24시간전부터는카페인이포함된식음료를제한하게하였다. 아데노신은주입펌프를사용하여 140 μg/kg/min의속도로 6분간정맥주사하였으며 Tc-99m MIBI 는 3분이경과한후에주사하였다. SPECT 영상은아데노신주입후약 60분후에시작하였다. 천식혹은만성폐쇄성호흡기질환, 2 혹은 3 방실차단이있는경우, 그리고수축기 / 이완기혈압이 90/60 mm Hg 이하일경우에는아데노신부하를실시하지않았다. 5. SPECT 영상획득 이중검출기 (ADAC, USA) 혹은삼중검출기감마카메라 (PRISM 3000, Picker, USA) 를이용하여 SPECT 영상을획득하였다. 감쇄및산란보정은하지않았고여과후역투사한후단축, 수직장축, 그리고수평장축단층사진을얻었다. 6. 영상판독 2명의핵의학과전문의가육안적으로판독하였다. SPECT 영상에나타난관류결손으로가역적결손은허혈, 고정결손은반흔조직, 그리고혼합된경우에는허혈이잔존하는반흔조직으로판정하였다 11-13). 7. 통계분석 SPSS software(version 12.0) 를이용하여통계분석하였다. 연속형변수는평균 ± 표준편차로표시하였고 Student's t test나 analysis of variance 를이용하여비교하였다. 범주형변수는 chi-square 나 Fisher's exact test를이용해서비교하였다. 여러임상인자들중에서독립적인예측인자를찾아내기위해로지스틱회귀분석방법을이용하였다. P value 0.05 1 4 미만인경우에통계적으로유의한것으로판단하였다. 결과 1. 환자들의임상적특징, SPECT 결과및심장사건 전체 203명의당뇨병환자중남자가 64명 (31.5%) 이었다. 평균연령은 64±9세였으며평균추적관찰기간은 11-56 개월 (36±18개월) 이었다. 환자들의임상적특징들은 Table 1 및 2에요약하였다. 운동부하심전도검사를시행한환자는 6명이었으며양성소견을보인환자는 1명, 진단이어려웠던경우가 1명이었으나, 증례수가적어통계적분석에는포함시키지않았다.(Table 3) 심근관류 SPECT 을시행한결과 58명 (28.6%) 에서관류이상소견이진단되었다. 환자들중추적관찰기간중에사망한예는 2건이었으나각각뇌출혈과당뇨병성신증으로사망하였으므로분석에서는제외하였다. 따라서조사기간중에는총 11건의중증심장사건, 즉비치명적심근경색이발생하였고 10건의경증심장사건이관찰되었다. 심근관류 SPECT 으로관류이상소견, 즉관동맥질환이진단된 58명의환자들중 8명 (13.8%) 에서중증심장사건이발생하였고관동맥질환이없는것으로진단된 145명의환자들중에서는 5명 (3.4%) 에서중증심장사건이발생하였다. 양성 으로판정된 SPECT 결과로는허혈이 46명 (22.7%) 으로가장많았고, 반흔조직이 8명 (3.9%), 허혈이잔존하는반흔조직이 4 명 (2.0%) 이었다. 2. 임상인자에따른관동맥질환의빈도본연구의대상자중여자가많았으나 SPECT 검사상관류이상소견을보여관동맥질환이진단된빈도는남자의경우 37.2% 로여자의 22.2% 보다유의하게높았다 (p=0.02). 당뇨병이환기간을 10년미만, 10년이상에서 20년미만, 20 년이상에서 30년미만, 그리고 30년이상의네군으로나누어분석하였을때각각 18.8%, 27.4%, 37.0%, 42.9% 로이환기간이길수록관동맥질환에이환된빈도가높았다 (p= 0.022). 이환기간을다시 20년미만과 20년이상의두군으로나누어분석하였을때통계적으로유의한차이를보였는데즉이환기간이 20년미만인환자들의 24.5% 에비하면 20년이상인환자들은 38.3% 로더높은관동맥질환빈도를나타내었다 (p=0.046). 당뇨병합병증들중말초혈관병증 (p=0.001) 과다발성말초신경병증 (p=0.026) 이있는환자들에서관동맥질환의빈도도유의하게높았다. 또한안정시심전도상이상이있었던환자들에서유의하게관동맥질환의빈도가높았다 (p=0.013). (Table 4) 157
Ji-Hyoung Seo, et al. Diagnosis of Coronary Artery Disease using Myocardial Perfusion SPECT in Patients with Diabetes Mellitus: Analysis of Risk Factors Table 4. Incidence of Myocardial Perfusion Defects in Relation to Clinical Variables Sex Male Female Age group -49 yrs 50-59 yrs 60-69 yrs 70-79 yrs 80 yrs- Angina Dyspnea Treatment OHA only OHA + insulin Diabetes duration <20 yrs 20 yrs Drinking Heavy Social Smoking HTN Dyslipidemia HbA1c <6% 6% Random blood glucose <200mg/dL 200mg/dL Retinopathy Peripheral vascular disease P (%*) P (%) χ 2 p 62.8 77.8 75.0 68.4 73.5 69.8 62.5 61.5 73.8 67.3 72.7 72.9 70.3 75.5 61.7 64.7 72.0 66.2 73.9 68.3 74.7 73.0 69.6 80.0 70.7 69.6 72.7 68.7 75.0 25.0 74.3 37.2 22.2 25.0 31.6 26.5 30.2 37.5 38.5 26.2 32.7 27.3 27.1 29.7 24.5 38.3 35.3 28.0 33.8 26.1 31.7 25.3 27.0 30.4 20.0 29.3 30.4 27.3 31.3 25.0 75.0 25.7 5.455 0.020 0.127 NS 2.314 NS 0.527 NS 0.164 NS 3.977 0.046 0.411 NS 1.304 NS 1.043 NS 0.286 NS 0.590 NS 0.245 NS 0.971 NS 13.405 0.001 Nephropathy Peripheral polyneuropathy Resting ECG rmal Abnormal 71.0 72.2 66.2 80.8 74.9 53.1 29.0 27.8 33.8 19.2 25.1 46.9 *P, perfusion defects on myocardial SPECT; OHA, oral hypoglycemic agent; HTN, hypertension. *incidence % 0.034 NS 4.928 0.026 6.236 0.013 158
서지형외. 당뇨병환자에서심근관류 SPECT 을이용한관동맥질환의진단 : 위험인자분석 Table 5. Incidence of Hard Events during the Follow-up Period in Relation to Clinical Variables Sex Male Female Age group -49 yrs 50-59 yrs 60-69 yrs 70-79 yrs 80 yrs- Angina Dyspnea Treatment OHA only OHA + insulin Diabetes duration <20 yrs 20 yrs Drinking Heavy Social Smoking HTN Dyslipidemia HbA1c <6% 6% Random blood glucose <200mg/dL 200mg/dL Retinopathy Peripheral vascular disease Nephropathy Peripheral polyneuropathy Resting ECG rmal Abnormal Hard event (%) event (%) χ 2 p 7.0 6.0 0.0 2.6 9.2 4.7 12.5 17.9 3.7 12.2 4.5 5.9 6.8 5.6 8.3 5.9 6.5 9.2 5.1 6.7 6.1 7.2 5.4 13.3 6.0 5.4 7.3 8.7 3.4 25.0 5.2 8.4 2.8 9.2 1.4 4.1 18.8 *OHA, oral hypoglycemic agent; HTN, hypertension. *incidence % 93.0 94.0 100.0 97.4 90.8 95.3 87.5 82.1 96.3 87.8 95.5 94.1 93.2 94.4 91.7 94.1 93.5 90.8 94.9 93.3 93.9 92.8 94.6 86.7 94.0 94.6 92.7 91.3 96.6 75.0 94.8 91.6 97.2 90.8 98.6 95.9 81.3 0.082 NS 1.291 NS 10.735 0.001 3.676 NS 0.066 NS 0.529 NS 0.008 NS 1.275 NS 0.038 NS 0.264 NS 1.223 NS 0.281 NS 2.324 NS 7.322 0.007 2.436 NS 4.796 0.035 9.661 0.002 159
Ji-Hyoung Seo, et al. Diagnosis of Coronary Artery Disease using Myocardial Perfusion SPECT in Patients with Diabetes Mellitus: Analysis of Risk Factors 3. 중증심장사건발생의예측인자전체당뇨병환자들의연간중증심장사건발생률은 1.1% 였다. 임상인자들의단변량분석의결과, 전형적인협심증상 (p=0.001), 말초혈관병증 (p=0.007), 다발성말초신경병증 (p=0.035), 그리고안정시심전도상이상소견 (p=0.002) 이중증심장사건의발생과유의한관련성이있었다.(Table 5) 그러나다변량분석하였을때에는전형적인협심증상 (p=0.005), 말초혈관병증 (p=0.021), 그리고안정시심전도상이상 (p=0.022) 만이중증심장사건, 즉비치명적심근경색발생에대한독립적인예측임상인자인것으로나타났다. 심근관류 SPECT 결과와관련해서는허혈이나반흔등의관류이상소견이있는경우에이상소견이없는경우보다중증심장사건의발생빈도가유의하게높아 (p=0.011) SPECT 검사상이상소견이중증심장사건발생의중요한예측지표가될수있음을보여주었다. 그러나단변량및다변량분석하였을때 SPECT 검사상이상소견이중증심장사건의독립적인예측인자인것은아니었다. 심근관류 SPECT 검사상정상결과를보인환자들의연간중증심장사건발생률은 0.6% 로관류이상소견이있었던환자들의경우 2.2% 였던것에비하면낮은발생율을나타내었다 (p=0.016). 고찰 당뇨병환자에서는무증상허혈이나심근경색으로나타나는빈도도높아서 1-4) 관동맥질환의진단이늦어지는환자가많다는점은심근관류스캔으로관동맥질환을평가하여야한다는중요한논리적근거가된다. 당뇨병환자들에서관동맥질환의빈도에대한일치된보고는없었으나, 현재까지보고된연구들을종합하여볼때비교적건강한당뇨병환자에서는약 20% 내외, 합병증이있는당뇨병환자에서는 50% 이상에서관동맥질환이있는것으로보고되었다. 14) 4736명의비교적많은수의당뇨병환자를대상으로하였던한후향적연구에서는 15) 무증상환자의 58.6%, 그리고증상이있는환자의 59.5% 에서심근관류 SPECT 으로관동맥질환이진단되었고이는당뇨병환자의경우협심증상의유무와관계없이관동맥질환이병합할확률이매우높다는사실을확인시켜주는결과이다. 그에비해최근의 DIAD(Detection of Ischemia in Asymptomatic Diabetics) 연구에서는무증상의당뇨병환자들을대상으로심근허혈의유병률을전향적으로조사하였는데대상환자의 22% 에서심근관류 SPECT 결과이상관류소견을보였다. 16) 본연구에서는 29.9% 의당뇨병환자들에게서관동맥질환이발견되었다. 소견별로는가역적결손 ( 허혈 ) 을보인예가 75.9% 로가장많았고다음으로고정결손 ( 반흔 ) 이 13.0%, 혼합된경우가 6.7% 순이었다. 본연구에서대상으로한환자들은관동맥질환의증상이나당뇨병이환기간과는상관없이무작위로검사를시행한경우가많아증상이없고비교적건강한당뇨병환자가대상에포함된경우가많았으며 (71.0%) 따라서관동맥질환의빈도가 DIAD 연구결과에비해서는높으나다른이전의연구결과들에비해서는비교적낮게나타났던것으로생각된다. 심근관류 SPECT 결과에따른예후를평가한연구결과를살펴보면 Felsher 등은 17) 심근관류 SPECT 상관류이상소견이진단되었던환자들에서심장사건이발생할위험도높았다고보고하였고이와유사한결과를보인연구들도다수찾을수가있다. 18-20) 본연구에서심근관류 SPECT 상관동맥질환이진단되었던당뇨병환자들에서향후심장사건발생빈도는연간 2.4% 로높았고, 반면에정상적인관류소견을나타내었던환자들의경우에는연간 0.6% 였다 (p=0.016). 추적관찰기간을통틀어발생했던관동맥질환의빈도를보면관동맥질환이없었던당뇨병환자에서는 3.8% 에서만이심장사건이발생했던반면관동맥질환이진단된당뇨병환자에서는 13.8% 에서비치명적심근경색이발생하였던것으로나타나역시유의한차이가있었다 (p=0.007). 심근관류 SPECT 상관찰되는관류이상의범위및중증도가직접적으로예후와관련이있다고알려져있으나, 21) 본연구에서는사용된감마카메라가다양하고동일한 software 를사용하지못한문제로모든환자들에게서일률적으로반정량적분석값을비교할수없었기때문에이부분은연구에서제외하였다. 본연구는당뇨병환자들에서관동맥질환의예측인자, 그리고심장사건발생의예측인자로어떤임상인자들이지표로사용될수있을지를알아보았다. 관동맥질환의고위험군으로예측할수있는임상인자에대해서는현재까지도이견이많은실정이다. 본연구에포함된환자들의성비는남자가 31.5% 로여자가두배이상많은수가포함되었으나관동맥질환의빈도는남자에게서유의하게높았다. 이것은이미알려져있듯성호르몬의차이, 즉 androgen 과 estrogen 의효과로도설명할수있겠으나 22) 남자환자중 12명 (18.8%) 이관동맥질환의중요한예측인자로알려져있는말초혈관병증이있었고반면에여자환자중에서는말초혈관병증을가진환자는없었다. 이런요인들이남자에서관동맥질환의빈도가더높게나타난근거로생각된다. 남녀환자들간에말초혈관병증이외의연령, 전형적인협심증상, 당뇨병이환기간, 안정시심전도이상, 당뇨합병증등임상인자들의차이는없었다. 단변량및다변량분석하였을때성별이관동맥질환 160
서지형외. 당뇨병환자에서심근관류 SPECT 을이용한관동맥질환의진단 : 위험인자분석 의독립적인예측인자인것은아니었다. 관동맥질환의예측인자들에대한지금까지의연구들에서는당뇨이환기간이 10년이상, 23) 당뇨합병증으로망막병증이나미세단백뇨가있거나, 24) 심장자율신경병증, 말초혈관병증, 25) 또는안정시심전도상이상 26) 이있는경우등이고위험군의예측인자들로보고되고있다. 1998년의미국당뇨병협회에서는두개또는그이상의관동맥질환의위험인자를가지고있는당뇨병환자의경우심장부하검사를권하였으나최근에는이런전통적인심장위험인자들이당뇨병환자의관동맥질환과연관성이낮았다는보고들이발표되고있으며특히 DIAD 연구에서는 16) 이미알려져있는심장위험인자들 5) 중에서고혈압, 흡연, 가족력, 그리고고지혈증이심근허혈의발생과는큰연관관계가없는것으로나타났다. 본연구의결과에서도 DIAD 연구에서와유사하게심장위험인자들, 즉고혈압, 흡연, 고지혈증, 그리고단백뇨는관동맥질환의발생과유의한상관관계가없었다. 그러나말초혈관병증과다발성말초신경병증이동반된환자들에서는관동맥질환의유병률과향후중증심장사건의발생이의미있게높았다. 다변량분석한결과는전형적인협심증상, 말초혈관병증, 그리고안정시심전도이상만이심장사건을예측할수있는독립적인인자로나타났다. 이들중에서는특히말초혈관병증이가장강한상관관계를보였다. 이것은당뇨병환자에서미세혈관기능장애 27,28) 가중요한병태생리임을고려한다면말초혈관병증을가진환자에서관동맥질환의위험이더높은것은당연한결과로생각된다. 심근관류 SPECT 결과관류이상소견이중증심장사건의독립적인예측인자로나타나지않았던것에대해서는, SPECT 검사상관류이상소견이나타나관동맥질환이진단된환자들에게는약물, 관동맥성형술, 혹은관동맥우회이식술등의치료가시행되어이후중증심장사건의발생을막을수있었던것으로보인다. 이점에대해서는향후장기간추적에의한치명률연구가필요할것이다. 본연구의제한점으로는반정량적분석이포함되지못했다는것이다. 또한좌심실기능의평가가일관되게이루어지지못해이것도연구에서제외되었다는점또한향후연구에서보완되어야할것으로생각된다. 결론 본연구의결과, 남자, 20년이상의긴당뇨병이환기간, 말초혈관병증, 다발성말초신경병증, 또는안정시심전도이상을가지고있는환자들에서높은빈도로 SPECT 검사상관동맥질환이진단됨을알수있었다. 그리고전형적인 협심증상, 말초혈관병증, 다발성말초신경병증, 안정시심전도이상이있는환자들에서이후심장사건이발생할위험이더큰것으로나타났다. 따라서이런고위험군의환자들을선별하여관동맥질환을조기에진단하고적절히치료하는것이이들환자에서심장사건으로인한사망률을낮추는데도움을줄수있을것이다. 요약 목적 : 당뇨병환자에서는관동맥질환의이환율이높고무통성심근경색과심근허혈의빈도가높아조기발견이어렵다. 또한진단될당시에이미심각한수준의관동맥질환을가지고있는경우가많다. 본연구에서는 Tc-99m MIBI 심근관류 SPECT 을이용하여당뇨병환자에서관동맥질환의빈도를평가하고전통적인심장위험인자들을포함한여러임상시험인자들중에서진단이필요한고위험군환자들을예측할수있는인자들을알아보고자하였다. 대상및방법 : 2000년 1월부터 2004년 7월사이에심근관류 SPECT 검사가의뢰된 203명의당뇨병환자 ( 남 64명, 평균연령 64.9±9.0 세 ) 를대상으로하였다. 심장사망및비치명적심근경색을중증심장사건으로정의하였고, 검사후 60일이후에경피적관동맥성형술이나관동맥우회수술을시행한정도의심근허혈의악화를경증심장사건으로정의하였다. 환자들은운동부하 (n=6) 혹은 adenosine (n=197) 부하 Tc-99m MIBI 심근관류 SPECT 을시행하였다. 이중검출기 (ADAC, USA) 혹은삼중검출기감마카메라 (PRISM 3000, Picker, USA) 를이용하여 SPECT 영상을획득하였다. 결과 : 심근관류 SPECT 결과관동맥질환이진단된환자들은 58명으로전체대상환자중 28.6% 였다. 총 11건의중증심장사건, 즉비치명적심근경색이발생하였고 10건의경증심장사건이관찰되었다. 전체대상당뇨병환자들의연간심장사건발생률은 1.1% 였다. 임상인자들의단변량분석결과, 전형적인협심증상, 말초혈관병증, 다발성말초신경병증, 그리고안정시심전도상이상이심장사건의발생과유의한관련성이있는것으로나타났다. 다변량분석에서는전형적인협심증상, 말초혈관병증, 그리고안정시심전도상이상만이비치명적심근경색발생에대한독립적인예측인자인것으로나타났다. SPECT 검사상관류이상소견이있었던환자들에게서중증심장사건이일어나는빈도도높았으나심장사건의독립적인예측인자는아니었다. 결론 : 당뇨병환자에서관동맥질환의빈도는정상건강인들에비해높았다. 특히남자, 20 년이상의긴당뇨병이환기간, 말초혈관병증, 다발성말초신경병증, 또는안정시심전도이상을가지고있는환자들에 161
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