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A ngina Pectoris , a film written and directed by J E F Riseman, won no Oscars, had no famous stars, and failed to secure even the most limited distribution deal. For those who have not seen the film, its actors are anonymous medical men demonstrating state of the art diagnostic assessment of patients with angina. A careful history of the characteristics of the pain and standardised investigation with resting and exercise electrocardiography are recommended. That all sounds familiar? Of course it does—not only professional bodies but even governments now issue guidance on such diagnostic assessments. The film was made in 1943. ![][1] Fred C Pampel, Seth Pauley Praeger Publishers, £22.99/$39.95, pp 248 ISBN 0275981517 www.greenwood.com/books/bookdetail.asp?sku=C8151 Rating:![Graphic][2] ![Graphic][3] Pampel and Pauley's book was published in 2004. In what sense have we made progress? Consider diagnosis. Clearly, many new diagnostic tests have been introduced in the six decades since Riseman's film. However, the proportion of patients undergoing coronary angiography in whom no narrowed arteries are detected—20% to 30%—has changed little in the past three decades. This raises the question … [1]: /embed/graphic-1.gif [2]: /embed/inline-graphic-1.gif [3]: /embed/inline-graphic-2.gif

Source Citation Michaelides AP, Psomadaki ZD, Dilaveris PE, et al. Improved detection of coronary artery disease by exercise electrocardiography with the use of right precordial leads. N Engl J Med...

： ： exercise echocardiography are widely used for evaluating coronary artery disease. In comparison with posttreadmill exercise echocardiography, supine bicycle stress echocardiography (SBSE has the advantage of imaging during stress and at peak exercise and ischemic wall motion abnormalities at the time of imaging are more frequent and more extensive. Therefore, SBSE is a valuable tool for evaluation of coronary artery disease. This study was designed to provide the hemodynamic changes during exercise and compare the sensitivity, specificity and predictive values of the wall motion abnormalities of supine bicycle stress echocardiography during peak exercise with those of 12-lead electrocardiography (ECG during exercise for evaluating coronary artery disease. Materials and Methods：One hundred patients for evaluation of possible coronary artery disease performed supine bicycle stress echocardiography. This study consisted of 51 patients who underwent coronary arteriography. Significant coronary artery disease was defined as the presence of ≥50% or ≥75% diameter reduction determined by magnified electronic caliper measurements, compairing the accuracy of supine bicycle stress echocardiography to that of 12-lead exercise ECG. Results：1 Fifty-one patients (31 men, 20 women underwent both supine bicycle stress echocardiography and coronary arteriography, the results were age (54.5±9.8 years, heart rates (68±12 vs 124±22 beats/min, systolic blood pressure (130±23 vs 175±32

으나 1941년에 이르러 비로소 심근허혈 동정에 심전 도의 가치를 인식하였다. 1952년에 YU 등이 Master 검사를 이용하여 ST분절 1mm 하강은 심근허 혈과 일치한다고 보고한 이래 이 기준은 운동부하 심전 도의 판정에 사용되고 있다. 관상동맥질환 환자에서 운 동으로 야기된 빈맥은 심내막하 허혈을 일으켜 정상적 인 심실재분극의 transmural gradient를 역전시켜 심 전도상에서 ST 분절의 하강을 발생시킨다. 표준 ST 하강 기준은 운동전과 비교하여 운동중 또는 운동후 회 복초기에 J-Point로 부터 60∼80 msec에서 ST 분절 하강을 측정하여 1 mm 이상 Horizontal 및 Downsloping ST 분절 하강을 측정하여 1mm 이상 Horizontal 및 Downsloping ST 분절 하강을 또는 1.5 mm 이상의 upsloping ST 분절의 하강을 양성 반응으로 판 정하고 있다. Gianrossi 등이 147개의 발표된 논문을 meta-analysis한 결과 평균 sensitivity는 68%(23∼ 100%), 평균 specificity는 77%(17∼100%)이고 다 혈관 질환에서는 평균 sensitivity는 81%(40∼100%), 평균 specificity는 66%(17∼100%)였다. 세혈관질환 또는 좌주간지 질환에서는 평균 sensitivity는 86±11%, 평균 specificity는 53±24%였다. 운동부하심전도는 이와같이 비교적 에민도가 낮고 예측 정확성이 낮아 임상적으로 한계가 있다. 임상가들은 운동중 영상기 법을 이용한 핵의학 검사를 더 널리 이용하게끔 되었 다. 그러나 이러한 핵의학 검사는 운동부하 심전도에 비하여 훨씬 고가이고 보편적으로 널리 이용될 수 없 는 실정이다. p676 참조

EDITOR,--C M Francis and colleague's report on open access echocardiography1 highlights the fears of many cardiologists about open access services.2 The principal aim of the author's service—the identification of patients with left ventricular dysfunction so that treatment with an angiotensin converting enzyme inhibitor could be started—occurred in only 50 (19%) of 259 patients, while valve disease was identified in 12. In a similar study of an open access exercise electrocardiography service McClements et al identified ischaemic heart disease in only 18% of the 192 patients tested.3 It is argued that a negative result of the test is reassuring, but many patients remain symptomatic despite reassurance.4 Furthermore, screening a low risk population …

It has been suggested that estrogen has a role in the genesis of false positive exercise electrocardiograms in women. We evaluated 1007 men and 832 women with suspected coronary artery disease concerning the accuracy of exercise electrocardiography. Women were grouped according to estrogen status (ES): ES- = postmenopausal and not on estrogen replacement and ES+ = premenopausal (Premen) or on estrogen replacement. Positive exercise ST criteria were ≥1 mm horizontal/downsloping or ≥1.5 mm upsloping depression. Results Overall accuracy: sensitivity 44% and specificity 87%; receiver operating characteristic curve (ROC) area 76 ± 3. The following table compares the accuracy of men and subgroups of women. Number Sensitivity Specificity ROC Area Men 1007 52 ± 7 91 ± 2 84 ± 3 Women 832 34 ± 7 82 ± 2 * 64 ± 6 * ES- 317 35 ± 12 79 ± 5 * 61 ± 9 * ES+ 515 15 ± 11 81 ± 2 * 46 ± 15 * Premen 259 72 ± 40 91 ± 5 ** 90 ± 14 † * p l 0.01 vs Men ** p = 0.05 vs ES+ or ES- † p l 005 vs Women, ES+, or ES The heart rate-pressure products for Men (26,600 ± 600) and Premen (26,500 ± 500) were the same (p = 0.58). Conclusion Concerning exercise electrocardiography, both ES+ and ES- women have lower accuracy than men. However, Premen women (a subgroup of ES+) had exercise performance and accuracy similar to men, especially concerning specificity. These results suggest that not all ES+ women have the same accuracy and argue against a role for naturally occurring estrogen as an etiology for false positive results.

Conventional exercise electrocardiographic criteria usually involve patterns with a horizontal or downsloping ST segment. In the present study we present criteria based on upsloping ST segments and compared these criteria with the conventional criteria. Using upsloping ST-segment criteria, the amount of ST-segment depression at 80 msec after the end of the QRS complex is used as a parameter (ST criterion E, with a depression of 100 mV, and ST criterion F, with a depression of 200 mV). In the graded exercise test a bicycle ergometer was used. The ECG leads were CM5 and CC5. The results of exercise electrocardiography were compared with the findings from coronary arteriography. In 623 selected patients (565 males and 58 females), application of conventional ST criteria gave a sensitivity of 56% and a specificity of 94%; with application of the ST criteria E or F, sensitivity was 75% and specificity 90%. In the 58 females use of these new criteria resulted in a sensitivity of 76% and specificity of 88%. Ninety-three patients (15%) could be classified as positive exercise responders by the sole presence of an upsloping ST segment (type E or F). Sixty-eight percent of the patients with type E and 75% with type F had two- or three-vessel disease (coronary obstructions greater their or equal to 50%). We conclude that ST criteria based on upsloping ST segments significantly increase the diagnostic yield of the exercise ECG.

The current CAA requirements for routine electrocardiographic surveillance of flyers is outlined, and the need for care in recording techniques is stressed. Electrocardiographs should meet current standards and be in good repair. Exercise electrocardiograms should not be employed routinely, except possibly for flyers over 50 years of age engaged in single-pilot commercial operations. Exercise tests are of value for individuals with equivocal symptoms or equivocal repolarization changes but the results should be interpreted as far as possible on the basis of probability analysis: to report tests as 'positive' without amplification and with implication of high predictive accuracy is unsatisfactory. The techniques of effort testing should be standardized, should be conducted with scrupulous attention to detail, and should be performed only in centres specified and approved for the evaluation of pilots' fitness to fly.

Thirty patients with angiographically documented mitral valve prolapse but without associated coronary artery disease, underwent exercise 201thallium myocardial scintigraphy. The resting ECG demonstrated ST segment abnormalities in 15 patients (50 percent). The exercise ECGs were abnormal in two patients (6.7 percent), normal in four (13.3 percent), and inconclusive in 24 patients (80 percent). Two patients (6.7 percent) had abnormal exercise myocardial scintigraphy (both patients had abnormal exercise ECGs). Two additional patients (6.7 percent) had perfusion abnormalities in the rest images that did not change with exercise. Twenty-six patients (86.4 percent) had normal scans. We conclude that the majority of patients with mitral valve prolapse have normal exercise 201thallium images in the absence of associated coronary artery disease and exercise electrocardiography is of limited value in patients with mitral valve prolapse because the results are frequently (80 percent) inconclusive.

トレッドミル (TM) テストと冠動脈造影を施行した93例を対象に, ST, R波, Q波の運動負荷試験の判定基準としての有用性およびQ波と心室中隔の灌流障害との関係を検討した。ST (V5) はsensitivity75%, specificity76%と良好だったが, R波, Q波の判定基準は問題があった。しかしSTの基準をもとにR波, Q波の基準を加えると, 補足的に発見率を高めることができた。TMによるQ波 (V5) の変動を調べたところ, 冠動脈狭窄群 (VD≧70%) にQ波の変動の少い例が多かった。左前下行枝と右冠動脈にGensini scoreを用いて冠動脈狭窄の程度をみると, Q波による陽性群の方が高値を示した (陽性群: 11.65±2.36, 陰性群: 5.80±1.72, ns) 。以上運動負荷試験の判定基準としてSTは良好だが, R波, Q波の単独使用は問題があった。しかし3者の組合わせ方により発見率を高めることができた。TMによるQ波 (V5) の変動の少い群に, 心室中隔の灌流障害が強い傾向がみられた。

l l2 for the clinical diagnosis of coronary artery disease (CAD). Each of these studies, however, rests on the tacit assumption that the sensitivity and specificity of the observations under consideration are invariant with respect to conventional clinical characteristics, changing only with the thresholds that one arbitrarily chooses as definitions of disease and abnormality and not, for instance, with the patient’s history. A recent study from Duke University casts serious doubt on the validity of this assumption.13 These investigators partitioned 2,269 patients who had undergone both stress electrocardiography and coronary angiography into various subsets on the basis of common clinical descriptors such as age, sex, exercise performance and the quality, severity or duration of symptoms. They then observed that the sensitivity of exercise-induced ST-segment depression as a marker of CAD ranged from 41 to 89%, whereas the specificity

The objective of this study was to determine whether exercise electrocardiography can be combined with thallium-201 myocardial imaging and the clinical history to exclude the diagnosis of coronary artery disease. All 96 patients in this study were referred for coronary angiography because of chest pain but did not have prior myocardial infarction; 52 percent had coronary artery disease. Each patient's chest pain was classified as either typical or not typical of angina pectoris. Negative tests with inadequate exercise stress (less than 85 percent of the age-predicted maximal heart rate) and combined tests with discordant results (either exercise electrocardiography or thallium imaging positive and the other test negative) were judged nondiagnostic. Nondiagnostic tests that contributed most to the uncertainty of results were classified separately: exercise electrocardiogram, 35 patients; thallium imaging, 9 patients; and combined exercise electrocardiogram and thallium imaging, 50 patients. The ability of each test to rule out coronary artery disease was defined by its predictive error (probability of coronary disease despite a negative test): history of chest pain not typical of angina, 26 percent (11 of 42); exercise electrocardiogram, 22 percent (5 of 23); thallium imaging, 27 percent (6 of 35); and negative findings on both exercise electrocardiogram and thallium imaging, 6 percent (1 of 17). Finally, when only the patients with atypical chest pain were considered, there was zero (0 of 15) predictive error if both tests were negative. Negative exercise electrocardiography and thallium imaging during adequate stress ruled out any coronary artery disease in these patients with considerable reliability (94 percent) and excluded multivessel disease with even greater reliability. These exclusion tests for coronary artery disease were most reliable in patients in whom the clinical diagnosis of coronary artery disease was least likely, as defined by Bayes' theorem. It is concluded that there is no perfect noninvasive test to exclude coronary disease in all patient populations; however, coronary angiography is not necessary to rule out the diagnosis of coronary artery disease in patients who'have (1) no clinical indicators of a very high probability of coronary disease, such as typical angina, (2) adequate exercise stress, (3) negative exercise electrocardiogram and (4) negative exercise thallium images.

Summary: In order to evaluate the efficacy of exercise electrocardiography (ECG) to identify jeopardized myocardial regions remote from the site of previous infarction, exercise ECG, left ventriculography, and coronary arteriography were performed in 90 patients with previous transmural myocardial infarction (MI). Of the 90 patients, angiographic studies revealed jeopardized myocardial regions in 47 patients. Exercise ECG correctly identified 32 of these 47 patients for a sensitivity value of 68%. There were 43 patients without any additional jeopardized myocardial regions. Exercise ECG correctly identifed only 24 of these 43 patients for a specificity value of 56 % . The sensitivity and specificity values were similar in patients with prior anterior and inferior wall MI. It is concluded that relatively low sensitivity and specificity values preclude the ability of exercise ECG to accurately identify patients with jeopardized myocardial regions distant from the site of previous MI. Moreover, when such patients were correctly detected, exercise ECG was rather poor in localizing these additional jeopardized myocardial areas.

The diagnostic sensitivity of visually interpreted and computer-analyzed 201Tl myocardial perfusion images was compared to that of exercise electrocardiograms in 8 angiographically normal subjects and 24 patients with significant coronary artery disease. Visual interpretation was not significantly better than exercise ECGs. An index of perfusion homogeneity, derived from computer analysis of the 201Tl images, was more sensitive than visual interpretation (79% vs. 58%) and much more sensitive (p less than 0.05) than the exercise ECG (79% VS. 46%). The best overall sensitivity (88%) and specificity (75%) were achieved by combining computer analysis with exercise electrocardiography. The computer also permits enhanced detection of subtle perfusion changes which may not seem significant to the eye.

Thirty-one patients with angina pectoris and 15 patients with myocardial infarction who performed exercise test by Master's double two-step test have been longitudinally followed up for 4-10 years. Exercise electrocardiogram was taken by Frank's lead and T loop was constructed in frontal and horizontal planes from 3 scalar tracings recorded at a paper speed of 100 mm/sec. ST vector was determined at 100 msec from the beginning of Q wave and the line connecting 2 ST vectors before exercise and at the point of the maximal ST change after exercise was determined as ST exercise vector. To indicate width of the T loop, the length to width ratio (L/W) was used and the change of width of the T loop induced by exercise was expressed by a ratio of L/W between before exercise and at the maximal change in frontal and horizontal planes. In cases having ST exercise vector of 0.1 mV or more the magnitude or the direction of the ST exercise vector alone has little prognostic value and widening of the T loop in addition to the ST exercise vector of 0.1 mV or more occurring after exercise was a predictive sign of poor prognosis and no widening of the T loop was a predictive sign of good prognosis.

The recent application of exercise electrocardiography in asymptomatic populations requires the physician to be aware of the differences in sensitivity, specificity, and predictive value when compared with its application in the symptomatic population. Strict application of standard testing methodology is necessary to assure valid data collection and to permit the most meaningful interpretation. The prevalence of the false-positive electrocardiogram is distressingly frequent and often eventuates in further diagnostic testing. The asymptomatic positive ECG response does increase the risk of development of overt manifestations of ischemic heart disease. Routine testing in the asymptomatic population should be limited to high-risk population subsets.

At a time of rapid increases in the cost of medical care and the application of complex invasive procedures to cardiovascular diagnosis, the use of noninvasive methods has aroused interest. This report discusses the usefulness and limitations of various noninvasive diagnostic methods including nuclear medicine techniques, echocardiography, exercise electrocardiography and determination of systolic time intervals. Emphasis is placed on the applicability of these methods to specific disease processes (such as ischemic heart disease, cardiac valve disease, pulmonary embolic disease), their relative merits, future potential and present shortcomings.

Exercise-induced electrocardiographic ST depression was compared during supine and erect graded bicycle exercise in 43 patients with chest pain but no prior myocardial infarct; all had greater than or equal to 1 mm of ST depression during either erect or supine exercise; 16 had multivessel, 24 had 1-vessel and 3 had no coronary artery disease. Supine exercise used 4 minutes/stage and erect exercise used either 4 minutes or 3 minutes/stage with identical graded work loads for both postures. Chest pain occurred in 31 patients during erect and in 29 during supine exercise. ST depression was greater than or equal to 1 mm in 28 patients during erect exercise and in all 43 during supine exercise (p less than 0.001); mean maximal ST depression was 1.3 +/- 0.2 mm during erect and 2.6 +/- 0.2 mm during supine exercise (p less than 0.001). Maximal work load was higher during erect than supine exercise (745 +/- 32 versus 678 +/- 32 kpm/min; p less than 0.001). The accentuation of ST depression by supine posture was not attributable to the changes in heart rate, rate-pressure product or mean blood pressure during supine versus erect exercise. In the 10 patients who had 2 erect bicycle tests using work load durations of 3 and 4 minutes, the maximal ST depression was not significantly different (erect 3 minutes 1.3 +/- 0.5 mm and erect 4 minutes 1.4 +/- 0.4 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

We tried to assess the efficacy of precordial exercise electrocardiography (PEE) in evaluating various antianginal drugs. PEE was performed by 18 precordial electrodes. Leads V2-V7 were recorded at their usual position and one intercostal space higher and lower. The Bruce treadmill exercise protocol was used. A positivity index (PI) was formulated as follows. The total sum of maximal ST-segment depression (sigma ST reduced) X 100 was divided by the product of the number of precordial leads X minutes of exercise duration: (Formula: see text). The PI was measured basally and after the administration of nitroglycerin (NTG) ointment, 7.5 mg (7 patients), propranolol (P) 20-40 mg, 3 times daily (7 patients) and nifedipine (N), 10 mg 3-4 times daily (7 patients). A significant decrease of the PI was seen with NTG (p less than 0.01) and P (p less than 0.05) but not with N. However, in the N group, 2 patients had a significant increase in heart frequency, with resultant exercise deterioration. The remaining 6 patients had a satisfactory response to the drug (p less than 0.05). The PI is useful in assessing the antianginal efficacy of various medications. From our study it is suggested that inordinate tachycardia may negate the beneficial effect of N in some patients.

In the past three decades, techniques that permit noninvasive quantitation of the function of the heart have been developed. Exercise electrocardiography has been widely used to determine the presence or absence of ischemic heart disease. Echocardiography permits detection of valvular, congenital and arteriosclerotic disease and quantitation of its severity. Selective use of isotopes allows nuclear angiogarphy, myocardial perfusion studies and detection of damage to cellular myocardium. New techniques such as computerized axial tomography, magnetometry, focused pulsed Doppler, and wider application of computer-enhanced image processing are important future directions for noninvasive monitoring.

Exercise electrocardiography is a valuable clinical tool with which quantitative evaluations and comparisons are now being attempted in many fields of cardiovascular investigation. Among a series of studies by a technical group on exercise electrocardiography, an assessment was made of observer variation in the clinical interpretation of ST-T responses during and after exercise. Interobserver variation among 14 cardiologists was great; individually assigned frequencies of abnormal responses after exercise in a mixed sample of records ranged from 5 to 58 per cent. Disagreement was greater for the diagnosis made during than for that made after exercise. Introbserver variation was also so great that use of the same observer for all exercise electrocardiographic readings would not necessarily provide acceptable reliability. The chief factors in disagreement were the lack of defined criteria for interpretation, in particular uncertainty about the significance of J-point ST-T depression, and technical quality of the records. Observer agreement was substantially increased when records were coded by unambiguous criteria or when simple measurements were made of the ST-T response after exercise.

A system of multiple-lead exercise electrocardiography has been applied to the study of 107 normal subjects and 67 patients with angina pectoris. The results of this test are compared to those of coronary cinearteriography in 84 patients. In-exercise ECGs gave useful additional information in 59% of the angina patients but were essential for interpretation in 9%. It added considerably to the safety of the test. The value of each individual lead and of the multiple lead system was assessed. Lead V 6 was the most often positive, but each made a contribution in some cases. Test-retest reproducibility survey indicated that five of 65 tests on 25 subjects failed to conform. Evidence has been presented that 1.0 mm of ischemic S-T segment shift was the best criterion for a positive test in the subjects studied. The test was positive in 84% of 67 patients with angina pectoris and 3.7% of 107 normal subjects (excluding vasoregulatory hyperreactors). The double two-step test given to the first 41 of the same angina patients for comparison was found to give 61% positive reactions despite the use of multiple leads and in-exercise recording. The test was administered to 84 subjects who were studied concurrently by selective coronary cinearteriograms and these two parameters were compared with the clinical diagnosis of angina in each patient. Since each of these parameters represents a different facet of coronary arterial disease, the agreement among them is very instructive.

Silent myocardial ischemia in now recognized to be a frequent occurrence in patients with coronary artery disease. Many of the recent observations regarding the occurrence of silent myocardial ischemia have been made using ambulatory electrocardiography, but silent ischemia can also be detected using exercise tests. These two forms of testing offer potentially complementary information. Exercise testing may be used to assess the extent and severity of “potentially inducible” silent myocardial ischemia, whereas ambulatory electrocardiography may be used to assess the frequency and duration of “spontaneously occurring” silent ischemia. In this article, we specifically focus on the frequency and prognostic implications of exercise-induced silent ischemia.

Exercise testing is a very valuable tool in clinical practice since it has many applications including diagnosis, screening, evaluating treatment and for the determination of prognosis and severity of disease. Its methodology has been varied but comparisons of methodology have been performed that make it possible to obtain comparable information from almost any method of testing. The addition of microprocessors to medical instrumentation and the use of nuclear imaging can improve exercise testing. Exercise testing also play an important role in cardiac rehabilitation and in the prescription of exercise for apparently healthy individuals.

The new approach to computer processing of exercise electrocardiography has been made easier by the development of microcomputers. Studies are necessary to validate analyzed electrocardiographic data for the diagnosis of ischemia. We describe and assess in this paper a new program for the analysis "on line" of 12 leads during effort. The program detects "normal QRS" and ectopic beats. Amplitude of R wave, length of QRS, ST level after a programmable delay from J point, ST maximal slope and amplitude of T wave are calculated and recorded every 15 sec in the 12 leads. In 200 exercise stress tests quantitative data provided by the processor were compared with visual analysis and with clinical data. ST level less than or equal to -0.8 mm and ST slope less than or equal to 1.2 mV/sec or ST level greater than or equal to +2.0 mm and ST slope less than or equal to 0.6 mV/sec were the best analyzed criteria for ischemia. Using these criteria, sensitivity increased from 86.6% by visual reading to 92% by computer analysis, without change in specificity (94%).

Summary: Serial exercise thallium-201 myocardial perfusion scanning (exercise and 4-hour redistribution) was compared to rest and exercise electrocardiography (ECG) for the detection of coronary artery disease in 125 patients with known or suspected coronary artery disease. All patients underwent coronary arteriography and 108 were found to have significant coronary artery lesions. The serial exercise thallium scan was significantly more sensitive than rest and exercise ECG in detecting coronary artery disease (94% v. 83% P