Left ventricular(LV) diastolic filling is abnormal at rest in many patients with coronary arery disease, even in the presence of normal resting LV systolic function. To determine the effects of improved myocardial perfusion on impaired LV diastolic filling and to detect the most sensitive parameter to assess LV diastolic function, gated radionuclide ventriculography were performed in 14 patients with coronary artery disease before and after successful percutaneous transluminal coronary angioplasty(PTCA). All patients had no previous myocardial infarction and no abnormal wall motion in gated radionuclide and contrast ventriculography. The following results were obtained; 1) There were no significant differences in the parameters of LV systolic function, such as peak ejection rate(PER, time to peak ejection rate(TPER), ejection fraction(EF) after successful PTCA. 2) Peak filling rate(PFR) and time to peak filling rate(TPFR), indexes of LV diastolic function, had no significant changes after successful PTCA. 3) The percent contribution of late diastolic filling to stroke volume(%LDF/SV) decreased from 26.5+/-6.8% to 19.1+/-6.6%(p<0.005 by paired t-test). These data suggest that in many patients with angina and normal LV systolic function, impaired global diastolic filling is a reversible manifestation of impaired coronary flow, and percent contribution of late diastolic filling to stroke volume(%LDF/SV) can be a sensitive parameter to evaluate impaired LV diastolic filling in coronary artery disease.
Angina Pectoris* ; Angioplasty, Balloon, Coronary* ; Coronary Artery Disease ; Gated Blood-Pool Imaging ; Humans ; Myocardial Infarction ; Perfusion ; Radionuclide Ventriculography ; Stroke

BACKGROUND AND METHOD: Pharmacological coronary vasodilation induced by dipyridamole is often used in association with thallium-201 scintigraphy to evaluate the presence and prognostic significance of coronary artery disease(CAD). Although dipyridamole has traditionally been used for this purpose, it causes frequent side effect, which at times can be life-threatening. Moreover, dipyridamole dose not elicit maximal coronary vasodilation in a substantial number of patients receiving the usual i.v. dose. Adenosine is an endogenously produced compound that has significant effects as a coronary vasodilator and rapid onset action and extremely short half-life(<10 seconds). The safety and diagnostic accuracy of intravenous adenosine Tc-99m MIBI imaging were evaluated in 248 patients who were referred for evaluation of CAD; 51 of the patients underwent coronary angiography and 25 of those exercise Tc-99 MIBI imaging. Adenosine was infused intravenously at a dose of 0.14 mg/kg/body weight per minute for 6 min and MIBI was injected at 3 min. RESULTS: Adenosine induced a significant decrease in systolic(p<0.05) and diastolic(p<0.001) blood pressures as well as a significant increase in heart rate(p<0.001) and rate-pressure product(p<0.01). The PR interval was slightly prolonged(p-NS). The overall sensitivity, specificity and predictive accuracy for CAD detection was 85%, 82%, and 83%, respectively. The diagnostic accuracy for individual CAD was low in left circumflex CAD. The agreement of segmental perfusion on adenosine and exercise Tc-99 MIBI imaging was 92% (Kappa index-0.83, p<0.001). Side effects occurred in 84% of 248 patients. Flushing (47%), dyspnea(45%), chest pain(28%) and headache(28%) were common. ST depression> or =1.0mm occurred in 8% and lst-, 2nd- and 3rd-degree atrioventricular block in 7%, 4%, and 1%, respectively. Side effects were mostly mild and transient except in 3 patients in whom premature termination of adenosine infusion and treatment were necessary. Aminophylline was used in only two patients. CONCLUSION: Thus, these facts suggest that pharmacological coronary vasodilation with adenosine in conjuction with Tc-99m MIBI myocardial scintigraphy appears to be a feasible, safe and valuable test for the diagnosis of coronary artery disease, particulary in patients unable to exercise.
Adenosine* ; Aminophylline ; Atrioventricular Block ; Coronary Angiography ; Coronary Artery Disease* ; Coronary Vessels* ; Diagnosis ; Dipyridamole ; Flushing ; Heart ; Humans ; Myocardial Perfusion Imaging ; Perfusion Imaging* ; Perfusion* ; Radionuclide Imaging ; Sensitivity and Specificity ; Thorax ; Vasodilation

BACKGROUND AND OBJECTIVES: The Duke treadmill exercise score (DTS) has been used to stratify patients with coronary artery disease into low-, moderate-, and high-risk groups. To determine the coronary angiographic and myocardial scintigraphic correlates of these scores, we have compared the degree of risk assessed by the DTS and with those obtained by angiography and SPECT. SUBJECTS AND METHODS: The subjects were classified into low risk (DTS >or= 5), moderate risk ( 4 > DTS >or= -11) and high risk (DTS < -11) groups according to their DTS. To evaluate the agreement in the risk assessment, 102 patients with angiographically proven coronary artery disease, were assessed for the extent of their coronary artery disease by the number of stenotic vessels, and from their exercise Tc-99m MIBI myocardial SPECT findings. RESULTS: Of the 102 subjects, 52 (51%) had one-vessel, 25 (24.5%) had two-vessel, and 25 had three-vessel disease. With the results of the coronary angiography and SPECT, the patients were re-classified into three groups; group 1 (n=20) had three-vessel disease and/or >10 abnormal segments, group 3 (n=41) had one vessel disease and less than 5 abnormal segments, and group 2 (n=41) included the remaining subjects. Based on the DTS, 37 (36%) were in the low-risk, 44 (43%) in the moderate risk, and 21 (21%) in the high risk groups. In the low-risk DTS patients, 32.4% were in group 1, 35.2% in group 2 and 32.4% in group 3. In relation to the subjects with moderate risk DTS, there were 9, 16 and 55% in groups 1, 2 and 3, respectively. Whereas, there were 19, 24 and 57% in groups 1, 2 and 3 with high risk DTS subjects, respectively. CONCLUSION: Although considerable overlap exists, the degree of risk assessed from the angiography and SPECT findings were different from those by DTS. We suggest that patients classified into the low-risk DTS group may have extensive coronary artery disease, or myocardial perfusion SPECT abnormalities, whereas patients in the high-risk DTS group may be normal, or have mild coronary artery disease or mild SPECT abnormalities.
Angiography ; Coronary Angiography ; Coronary Artery Disease* ; Coronary Vessels* ; Exercise Test ; Humans ; Perfusion ; Radionuclide Imaging ; Risk Assessment* ; Tomography, Emission-Computed, Single-Photon

BACKGROUND: Transluminal balloon coronary angioplasty is one of the most widely used therapeutic procedures in the treatment of patients with coronary artery disease. However, restenosis remains a major limitation of percutaneous coronary angioplasty despite extensive efforts to prevent recurrence. We examined the immediate and long-term results of 516 patients (617 lesions) who underwent coronary angioplasty to evaluate the initial success rate, complications, restenosis rate, and the factors affecting initial success and restenosis. METHODS: The coronary angioplasty of 516 patients(M/F : 388/128, mean age : 57 years), 671 lesions was done with conventional technique and follow-up coronary angiogram was obtained 4 to 6 months after angioplasty in 168 patients. The angiographic restenosis was defined as >50% luminal narrowing in a previously dilated lesion, and the clinical restenosis defined as the recurrence of typical angina and/or positive tests of treadmill test, or thallium scintigraphy during follow-up period. RESULTS: 1) The coronary angioplasty was successful in 459 of 516 patients(89%), 604 of 671 lesions(90%). The success rate was significantly lower in subgroups with type C lesion(52.2%, p<0.001), right coronary artery (83.7%, p<0.05) and <3.0mm of size of lesion(81.4%, p<0.001). 2) The procedural complications were as follows : intimal dissection in 143 lesions(21.3%) including acute closure in 9 lesions(1.3%), emergency bypass surgery in 6 patients(1.2%), myocardial infarction in 9 patients(1.7%), rupture of coronary artery in 2 patients, air embolism in 1 patient, and death in 1 patient(0.19%). 3) The causes of the procedural failure(n=57 patients) included guidewire passage failure in 27, balloon passage failure in 4, catheter engagement failure in 1, acute closure in 7, coronary artery rupture in 2, and suboptimal result in 16 patients. 4) Clinical follow-up was obtained in 455 patients for a mean follow-up duration of 13.2months and clinical restenosis rate was 31%(141/455). The repeat coronary angiogram was performed in 168 patients(209 lesions) for a mean follow up duration 5.4month and demonstrated 48%(100/209) angiographically restenosis rate. The clinical restenosis rate was significantly lower in subgroups with <10% of residual stenosis(18.9%, p<0.05), left circumflex coronary artery(18.5%, p<0.05). 5) The restenosis following angioplasty(n=100 lesions) was treated with repeated PTCA in 57, Stent(Palmaz-Schatz) in 6, DCA in 3, elective CABG in 9, and medication in 25. 6) During the clinical follow-up, there were nonfatal myocardial infarction in 4 patients. CONCLUSION: 1) The coronary angioplasty is an effective treatment for revascularization that has a high success rate, low incidence of complications and excellent long-term survival. 2) The restenosis rate was affected by residual stenosis which suggests that the implication of minimal residual stenosis is the most important determining factor to reduce the restenosis rate after angioplasty.
Angioplasty* ; Catheters ; Constriction, Pathologic ; Coronary Artery Disease ; Coronary Vessels ; Embolism, Air ; Emergencies ; Exercise Test ; Follow-Up Studies ; Humans ; Incidence ; Myocardial Infarction ; Phenobarbital ; Radionuclide Imaging ; Recurrence ; Rupture ; Thallium

OBJECTIVE: The aim of this study was to investigate the most robust predictor of myocardial viability among stress/rest reversibility (coronary flow reserve [CFR] impairment), 201Tl perfusion status at rest, 201Tl 24 hours redistribution and systolic wall thickening of 99mTc-methoxyisobutylisonitrile using a dual isotope gated myocardial perfusion single-photon emission computed tomography (SPECT) in patients with coronary artery disease (CAD) who were re-vascularized with a coronary artery bypass graft (CABG) surgery. MATERIALS AND METHODS: A total of 39 patients with CAD was enrolled (34 men and 5 women), aged between 36 and 72 years (mean 58 +/- 8 standard in years) who underwent both pre- and 3 months post-CABG myocardial SPECT. We analyzed 17 myocardial segments per patient. Perfusion status and wall motion were semi-quantitatively evaluated using a 4-point grading system. Viable myocardium was defined as dysfunctional myocardium which showed wall motion improvement after CABG. RESULTS: The left ventricular ejection fraction (LVEF) significantly increased from 37.8 +/- 9.0% to 45.5 +/- 12.3% (p < 0.001) in 22 patients who had a pre-CABG LVEF lower than 50%. Among 590 myocardial segments in the re-vascularized area, 115 showed abnormal wall motion before CABG and 73.9% (85 of 115) had wall motion improvement after CABG. In the univariate analysis (n = 115 segments), stress/rest reversibility (p < 0.001) and 201Tl rest perfusion status (p = 0.024) were significant predictors of wall motion improvement. However, in multiple logistic regression analysis, stress/rest reversibility alone was a significant predictor for post-CABG wall motion improvement (p < 0.001). CONCLUSION: Stress/rest reversibility (impaired CFR) during dual-isotope gated myocardial perfusion SPECT was the single most important predictor of wall motion improvement after CABG.
Adult ; Aged ; Analysis of Variance ; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography/*methods ; Coronary Artery Bypass ; Coronary Artery Disease/physiopathology/*radionuclide imaging/surgery ; Coronary Circulation/*physiology ; Coronary Disease/radionuclide imaging/surgery ; Female ; Humans ; Male ; Middle Aged ; Myocardial Contraction/physiology ; Myocardium ; Nitriles/diagnostic use ; Stroke Volume/physiology ; Technetium/diagnostic use ; Ventricular Function, Left/physiology

Acute renal infarction is an uncommon disease which is often delayed or missed due to its rarity and unspecific clinical presentations. Most patients have an underlying disease or embolic event that can be detected easily by history and physical examination. The frequently noted symptoms include flank, abdominal, and back pain, as well as nausea. The pain is usually acute, severe, and sharp in nature without radiation. The most sensitive laboratory test is lactate dehydrogenase. Angiography, renal scintigraphy, IVP (intravenous pyelography), sonography and, CT (computed tomography) can be used in diagnosing renal infarction. However, CT is more preferred for the diagnosis of renal infarction because it has the advantages of easy accessability and noninvasiveness. Once diagnosed, conservative treatment with intra-arterial infusion of thrombolytics or heparin appears to be the most favorable modality. We report a 82-year-old male with asynchronous bilateral renal infarctions associated with atrial fibrillation and coronary artery disease. His clinical status improved during admission without any events.
Aged, 80 and over ; Angiography ; Atrial Fibrillation* ; Back Pain ; Coronary Artery Disease ; Diagnosis ; Heparin ; Humans ; Infarction* ; Infusions, Intra-Arterial ; Korea* ; L-Lactate Dehydrogenase ; Male ; Nausea ; Physical Examination ; Radionuclide Imaging

The first step to nuclear medicine in Korea started with introduction of the gamma camera in 1969. Although planar images with the gamma camera give important functional information, they have the limitations that result from 2-dimensional images. Single-photon emission computed tomography (SPECT) due to its 3-dimensional image acquisition is superior to earlier planar gamma imaging in image resolution and diagnostic accuracy. As demand for a hybrid functional and anatomical imaging device has increased, integrated SPECT/CT systems have been used. In Korea, SPECT/CT was for the first time installed in 2003. SPECT/CT can eliminate many possible pitfalls on SPECT-alone images, making better attenuation correction and thereby improving image quality. Therefore, SPECT/CT is clinically preferred in many hospitals in various aspects.More recently, additional SPECT/CT images taken from the region with equivocal uptake on planar images have been helpful in making precise interpretation as part of their clinical workup in postoperative thyroid cancer patients. SPECT and SPECT/CT have various advantages, but its clinical application has gradually decreased in recent few years. While some researchers investigated the myocardial blood flow with cardiac PET using F-18 FDG or N-13 ammonia, myocardial perfusion SPECT is, at present, the radionuclide imaging study of choice for the risk stratification and guiding therapy in the coronary artery disease patients in Korea. New diagnostic radiopharmaceuticals for AD have received increasing attention; nevertheless, brain SPECT will remain the most reliable modality evaluating cerebral perfusion.
Ammonia ; Brain ; Coronary Artery Disease ; Gamma Cameras ; Humans ; Korea ; Nuclear Medicine ; Perfusion ; Radionuclide Imaging ; Radiopharmaceuticals ; Thyroid Neoplasms ; Tomography, Emission-Computed ; Tomography, Emission-Computed, Single-Photon

The clinical utility of thallium-201 SPECT combined dwith pharmacologic vasodilation induced by oral dipyridamole as an alternatiove to intravenous dipyridamole was incestigated in 21 patients who had concomitant coronary arteriography. Tomographic images were assessed visually. Sensitivity & specificity for overall detection of coronary artery disease were 93.7% and 80% respectively. Sensitivity & specificity for identification of indevidual diseased vessels were 84.6% and 87.5% for the left anterior descending artery, 75% and 84.6% for the right coronary artery, 60% and 100% for the left circumflex artery, respecitively. Of the 26 patients unergoing thallium scintigraphy 11 patients(42.3%) had some adverse effects between 20 and 50 minutes after oral dipyrdamole ingestion, including headache(26.9%), chest pain(26.9%), electrocardiographic changes(19.2%), and nausea(11.5%). Intravenous aminophylline was used to resolve these adverse effects in 8 patients & most of the adverse effects were subsided within 10 minutes. There was no ventricular arrhythmias, myocardial infarctions or deaths. In conclusion, oral dipyridamole thallium-201 SPECT is safe and accurate test for the overall detection of coranary artery disease and identification of disease in individual arteries. Furthermore it is useful for determining the necessities of coronary reperfusion and prognstically stratiofying the patients with coronary artery disease.
Aminophylline ; Angiography ; Arrhythmias, Cardiac ; Arteries ; Coronary Artery Disease* ; Coronary Vessels* ; Dipyridamole* ; Eating ; Electrocardiography ; Humans ; Myocardial Infarction ; Myocardial Perfusion Imaging* ; Myocardial Reperfusion ; Radionuclide Imaging ; Sensitivity and Specificity ; Thallium ; Thorax ; Tomography, Emission-Computed, Single-Photon* ; Vasodilation

BACKGROUND: Myocardial perfusion scintigraphy with intravenous adenosine has proved efficacy for the diagonosis and risk stratification of coronary artery disease. To determine the safety of adenosine infusion in conjunction with radionuclide imaging, we evaluated prospectively 1,093 patients who underwent myocardial perfusion study. METHODS: Informations on safety and adverse events during and immediately after adenosine infusion were collected and statistical analysis was performed. RESULTS: The adverse events were reported in 730 patients (66.8%), but no death or myocardial infarction. There asverse events were well tolerated and no prolonged effect was noted. Chest pain occured in 223 patients(20.4%) and facial flushing and dyspnea were reported by 246 patients(22.5%) and 253 patients(23.1%), respectively. ECG changes, such as mild arrhythmia, ST depression and AV block were checked in 230 patients(21.0%). The infusion was prematurely terminated in 32 patients(2.9%), due to serve chest pain, serve brochospasm, or third degree AV block. Higher frequency of chest pain was reported in women compare to men(p<0.05), and ST segment depression was more frequent in patients with abnormal myocardial perfusion scitigraphic findings(p<0.05). CONCLUSION: These results demonstrate that intravenous infusion of adenosine is relatively safe, and myocardial perfusion scintigraphy with intravenous ademosine is feasible technique in the evaluation of the coronary artery disease patients unable to exercise.
Adenosine* ; Arrhythmias, Cardiac ; Atrioventricular Block ; Chest Pain ; Coronary Artery Disease ; Depression ; Dyspnea ; Electrocardiography ; Female ; Flushing ; Humans ; Infusions, Intravenous ; Myocardial Infarction ; Myocardial Perfusion Imaging* ; Perfusion ; Perfusion Imaging ; Prospective Studies ; Radionuclide Imaging

OBJECTIVE: Gated myocardial perfusion single-photon emission computed tomography (GSPECT) has been established as an accurate and reproducible diagnostic and prognostic technique for the assessment of myocardial perfusion and function. Respiratory motion is among the major factors that may affect the quality of myocardial perfusion imaging (MPI) and consequently the accuracy of the examination. In this study, we have proposed a new approach for the tracking of respiratory motion and the correction of unwanted respiratory motion by the use of respiratory-cardiac gated-SPECT (RC-GSPECT). In addition, we have evaluated the use of RC-GSPECT for quantitative and visual assessment of myocardial perfusion and function. MATERIALS AND METHODS: Twenty-six patients with known or suspected coronary artery disease (CAD)-underwent two-day stress and rest (99m)Tc-Tetrofosmin myocardial scintigraphy using both conventional GSPECT and RC-GSPECT methods. The respiratory signals were induced by use of a CT real-time position management (RPM) respiratory gating interface. A PIO-D144 card, which is transistor-transistor logic (TTL) compatible, was used as the input interface for simultaneous detection of both ECG and respiration signals. RESULTS: A total of 26 patients with known or suspected CAD were examined in this study. Stress and rest myocardial respiratory motion in the vertical direction was 8.8-16.6 mm (mean, 12.4 +/- 2.9 mm) and 7.8-11.8 mm (mean, 9.5 +/- 1.6 mm), respectively. The percentages of tracer intensity in the inferior, inferoseptal and septal walls as well as the inferior to lateral (I/L) uptake ratio was significantly higher with the use of RC-GSPECT as compared to the use of GSPECT (p < 0.01). In a left ventricular ejection fraction (LVEF) correlation analysis between the use of rest GSPECT and RC-GSPECT with echocardiography, better correlation was noted between RC-GSPECT and echocardiography as compared with the use of GSPECT (y = 0.9654x + 1.6514; r = 0.93, p < 0.001 versus y = 0.8046x + 5.1704; r = 0.89, p < 0.001). Nineteen (19/26) patients (73.1%) showed abnormal myocardial perfusion scans with reversible regional myocardial defects; of the 19 patients, 14 (14/26) patients underwent coronary angiography. CONCLUSION: Respiratory induced motion can be successfully corrected simultaneously with the use of ECG-gated SPECT in MPI studies using this proposed technique. Moreover, the use of ECG-gated SPECT improved image quality, especially in the inferior and septal regions that are mostly affected by diaphragmatic attenuation. However, the effect of respiratory correction depends mainly on the patient respiratory pattern and may be clinically relevant in certain cases.
Aged ; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography/*methods ; Coronary Artery Disease/radionuclide imaging ; *Coronary Circulation ; Electrocardiography ; Female ; Humans ; Male ; Middle Aged ; Organophosphorus Compounds/diagnostic use ; Organotechnetium Compounds/diagnostic use ; Radiopharmaceuticals/diagnostic use ; *Respiration