Anatomic and functional significance of a hypotensive response during supine exercise radionuclide ventriculography

The significance of a decline in systolic blood pressure (BP) during supine exercise was examined in 820 patients who underwent both supine exercise gated equilibrium radionuclide ventriculography and coronary angiography. Twenty-seven patients, 3% of the study population, had a decrease in systolic BP at peak exercise of more than 10 mm Hg from the systolic BP at rest. Other indicators of ischemia--angina, ST-segment depression, a decrease in ejection fraction and wall motion abnormality during exercise--were present frequently but not uniformly in these patients. Although most patients had a decline in ejection fraction and a new wall motion abnormality with exercise, 4 patients had an increase in ejection fraction with exercise without any regional wall motion abnormalities. Coronary angiography in the 27 patients with systolic hypotension demonstrated severe coronary artery disease (CAD). Twenty-two patients (81%) had 3-vessel or left main CAD. Twenty of these 22 patients with 3-vessel CAD had at least 2 arteries with 90% or more diameter stenoses. Systolic hypotension during supine exercise radionuclide angiography is infrequent, usually associated with evidence of global and regional left ventricular dysfunction, and a marker of very severe CAD.     

Value and mechanism of abnormal postexercise systolic blood pressure response for detection of coronary artery disease]

The value of an abnormal ratio of recovery systolic blood pressure to peak exercise SBP for detecting coronary artery diseases (CAD) is controversial. We evaluated the ratio in 39 patients with angiographically documented CAD and 52 patients with normal coronary artery undergoing treadmill exercise. If a response with the ratio higher than 1.0 and 0.8 at 1 and 3 min. of recovery was considered as abnormal, the sensitivity for detecting CAD was 66.7%, the specificity 73.1% and the accuracy 70.3%. If ST segment depression is combined into the criteria, the specificity and accuracy reach 94.2% and 76.9%. In CAD, the ratio at 3 min. of recovery showed significant negative correlation with resting left ventricular ejection fraction (LVEF) (r = -0.461, P < 0.01). It is suggested that low resting LVEF may be one of the mechanism of this abnormal ratio in CAD.     

Exercise ultrafast computed tomography for the detection of coronary artery disease

Ultrafast computed tomography permits the assessment of global and regional left ventricular function during exercise. To evaluate the feasibility of using this new technique for the diagnosis of coronary artery disease, 27 patients undergoing cardiac catheterization for diagnosis of chest pain were evaluated. Fifteen patients had significant (greater than 50%) coronary artery stenosis by quantitative coronary angiography. One vessel disease was found in 12 patients and multivessel disease in 3. Fourteen (93%) of the 15 patients with significant coronary stenosis had a decrease in ultrafast computed tomographic ejection fraction during exercise from (mean +/- SD) 65 +/- 7% to 60 +/- 7% (p less than 0.001). The tomographic ejection fraction increased greater than 5% units during exercise in 10 (83%) of the 12 patients with normal coronary arteries. The mean tomographic ejection fraction in this group was 68 +/- 6% at rest and 75 +/- 6% at peak exercise (p less than 0.001). Regional wall motion was quantified by analyzing the segmental ejection fraction of 12 30 degree pie segments at each tomographic level of the left ventricle. A new regional wall motion abnormality developed during exercise in 12 (86%) of 14 patients with coronary artery disease; one patient was excluded because of a technical problem in data storage. Eleven (93%) of the 12 patients with normal coronary arteries had normal wall motion during exercise. In no patient with ischemic heart disease were both variables, ejection fraction response and regional wall motion, normal. Exercise ultrafast computed tomography appears to be a useful technique for the evaluation of coronary artery disease in patients with chest pain and predominant single vessel coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)     

Response of the right ventricle to exercise in isolated mitral stenosis

Eight patients in sinus rhythm, with varying degrees of isolated mitral stenosis (mitral valve area 0.6 to 1.3 cm2 and total pulmonary vascular resistance 5.0 to 17.5 U-m2), underwent supine rest and symptom-limited exercise radionuclide ventriculography to determine right ventricular (RV) and left ventricular ejection fraction (EF). Cardiac catheterization with hemodynamic measurements at rest and at peak exercise was performed within 24 hours of radionuclide ventriculography. Four of the 8 patients underwent corrective mitral surgery resulting in normal mean pulmonary artery pressures and total pulmonary vascular resistance at rest. These 4 patients had repeat radionuclide ventriculography at rest and during exercise 1 to 2 months after surgery. Preoperatively, all 8 patients had an abnormal exercise RVEF response (mean change +/- standard deviation [SD], -5.0 +/- 4.5%), coincident with an increase in mean pulmonary artery pressure during exercise (mean change, 15 +/- 5.0 mm Hg). The change in RVEF from rest to exercise, corrected for duration of exercise, correlated with peak exercise mean pulmonary artery pressure (r = -0.71, p = 0.05), as well as total pulmonary vascular resistance at rest (r = -0.82, p = 0.02). Postoperatively, all 4 patients who underwent surgical correction showed a normal RVEF response during exercise (mean change +/- SD, +6.8 +/- 4.0%). Thus, in patients with acquired mitral stenosis and no coronary artery disease (1) loading conditions and not contractility are prime determinants of RV exercise response, and (2) an exercise-induced decrease in RVEF may be a sensitive marker for increased total pulmonary vascular resistance and pulmonary hypertension.     

Superiority of supine bicycle over isometric handgrip exercise in the assessment of ischemic heart disease: An evaluation of left ventricular ejection fraction response using radionuclide angiography

Left ventricular ejection fraction (LVEF) response to supine bicycle and isometric handgrip exercise was evaluated in 15 patients with documented coronary artery disease (CAD) and stress-induced ischemia using radionuclide angiography. For purposes of analysis, the patients were divided into two groups: group I (n=7) with single-vessel disease and group II (n = 8) with multiple-vessel disease including 3 with left main artery disease. The studies were repeated 18 days later at similar external workloads to assess reproducibility of both tests. LVEF response to bicycle exercise was different for the two groups. The change in LVEF from rest to peak exercise was +0.04±0.02 for group I and -0.07±0.04 for group II (p <.001). LVEP response to isometric handgrip exercise was not different between the two groups. The change from rest to end of handgrip exercise was -0.02+0.02 for group I and -0.05 ±0.02 for group II. The reproducibility of LVEF response to bicycle exercise at similar workloads on day 1 and day 19 was good (r=0.85) while it was poor for isometric handgrip testing (r=0.67). Our data demonstrate that radionuclide angio-graphic measurement of LVEF response to supine bicycle exercise testing is superior to LVEF response to isometric handgrip testing in the evaluation of patients with CAD.     

Effect of left ventricular global systolic function, mitral regurgitation, and left ventricular inflow pattern on exercise echocardiography results

Diagnosis of coronary artery disease (CAD) by exercise echocardiography is usually based on rest or exercise-induced regional wall-motion abnormalities. Mitral regurgitation (MR), left ventricular (LV) global systolic function, and LV inflow measurements can be assessed during exercise echocardiography; however, their diagnostic value has not been analyzed consistently. Treadmill exercise echocardiography and coronary angiography were performed in 120 patients (94 male, 26 female; mean age 61 +/- 10 years [+/- 1 SD]) to evaluate known or suspected CAD. Positive exercise echocardiography was defined either as a rest- or exercise-induced regional wall-motion abnormalities. An abnormal response of LV ejection fraction (EF), LV volumes, MR (as assessed by color Doppler), and LV inflow pattern was defined as a fall in LVEF, a LV end-diastolic volume increase, a LV end-systolic volume increase, a new or increased MR, or a change from an impaired relaxation pattern (E < A) to a "pseudonormalized" pattern (E > A) from rest to exercise, respectively. CAD (> or = 50% luminal narrowing in at least one vessel) was found in 89 (74%) patients. EE-based regional wall-motion abnormality analysis was positive in 95 (79%) patients and negative in 25 (21%) patients. Feasible images for regional wall-motion abnormalities, LVEF and volumes, LV inflow, and MR measurements were acquired in 90% of patients. Regional wall-motion abnormality analysis and LVEF decrease provided the greatest sensitivities for CAD (94% and 75%, respectively), while the highest specificity was given by a new or increased MR (90%), the development of a pseudonormalized pattern (88%), and the appearance of angina (87%). A positive electrocardiogram (ECG) finding in patients with interpretable ECGs provided good sensitivity and specificity (67% and 85%, respectively). In conclusion, a complete rest and exercise Doppler echocardiography approach is feasible in most patients. Regional wall-motion abnormalities are the most accurate exercise echocardiography variable for diagnosing CAD, whereas exercise ECG remains a good test in patients with interpretable ECGs. Exercise echocardiography, exercise ECG, newly developed or increased MR, and change to a pseudonormalized LV inflow pattern are highly specific.     

Exercise radionuclide ventriculography in evaluating successful transluminal coronary angioplasty

To evaluate the ability of transluminal coronary angioplasty (TCA) to relieve myocardial ischemia, 44 patients with single vessel disease underwent exercise gated radionuclide ventriculography (GRNV) before and 2.8 +/- 1.3 days following angiographically successful TCA. Pre-TCA GRNV was abnormal in 11 of 14 patients with right coronary artery (RCA) stenosis and 24 of 30 with left anterior descending (LAD) stenosis. Following TCA there was an increase in exercise duration from 500 +/- 288 sec to 625 +/- 273 sec (P less than 0.001), and in maximum double product from (209 +/- 69) x 10(2) to (263 +/- 70) x 10(2) (P less than 0.001). The number of patients with stress-induced ST-T abnormalities decreased from 13 to 4 (P less than 0.05), and the number with chest pain during exercise decreased from 18 to one (P less than 0.001). Whereas resting ejection fraction was unchanged (0.58 +/- 0.10 vs 0.59 +/- 0.11) following TCA, the ejection fraction at peak exercise increased from 0.61 +/- 0.13 to 0.66 +/- 0.12 (P less than 0.001). Of 24 patients with resting abnormalities, regional wall motion improved in 13. In 22 of 31 patients with stress-induced asynergy, the wall motion response to exercise improved (P less than 0.001). Of 19 patients restudied angiographically and with exercise GRNV at 6-12 months, restenosis of greater than or equal to 50% had occurred in six, four of whom had abnormal studies. In six of whom the degree of stenosis of the dilated artery had remained less than or equal to 20% the exercise GRNV study remained normal. It is concluded that GRNV is helpful in documenting the improvement in resting left ventricular function and functional reserve in patients with angiographically successful TCA. In the limited number of patients with late follow-up studies, data suggest that GRNV may be a valuable test to detect restenosis.     

Clinical and hemodynamic significance of left ventricular diastolic volume changes by exercise radionuclide ventriculography in coronary artery disease

Recent studies have suggested that left ventricular (LV) dilatation during exercise radionuclide ventriculography may identify coronary artery disease (CAD). Coronary anatomy and LV end-diastolic pressure at catheterization were compared with results of supine exercise radionuclide ventriculography in 66 patients evaluated for chest pain. Forty-six patients had significant CAD (greater than 75% diameter stenosis) and 20 patients were normal. Radionuclide ventriculography was performed within 18 hours of catheterization, at rest and at peak exercise. Relative LV end-diastolic volumes were extrapolated from end-diastolic counts. LV end-diastolic counts increased during exercise in 19 of 20 normal subjects. In patients with CAD, LV end-diastolic counts increased in 35 (group A) and decreased in 11 (group B). The percent change in LV end-diastolic counts from rest to exercise, rest ejection fraction, exercise ejection fraction and rest LV end-diastolic pressure for each group were 20 +/- 23%, 60 +/- 13%, 67 +/- 13% and 8 +/- 3 mm Hg in normal subjects; 20 +/- 20%, 50 +/- 12%, 47 +/- 13% and 12 +/- 4 mm Hg in group A; and -9 +/- 8%, 54 +/- 21%, 49 +/- 18% and 21 +/- 7 mm Hg in group B (mean +/- standard deviation). An increase in LV end-diastolic counts was unrelated to ejection fraction response or presence of underlying CAD but only correlated to rest LV end-diastolic pressure (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Coronary flow reserve of the angiographically normal left anterior descending coronary artery in patients with remote coronary artery disease

Coronary artery disease (CAD) has been suggested to alter coronary flow reserve (CFR; the ratio between hyperemic and baseline coronary flow velocities) not only in territories supplied by stenotic arteries but also in angiographically normal, remote regions. However, few data exist regarding the left anterior descending (LAD) coronary artery as the normal index artery. The influence of remote CAD on CFR of the angiographically normal LAD was evaluated with transthoracic Doppler ultrasound to measure CFR in the LAD during 90 seconds of venous adenosine infusion (140 microg/kg/min) in 122 subjects who were assigned to 1 group; group 1 comprised 49 controls without angiographically detectable CAD, and group 2 consisted of 73 patients with an angiographically normal LAD and remote CAD. Group 2 was divided into 4 subgroups: 16 patients with previous remote percutaneous coronary intervention (group 2A); 13 patients with significant remote stenosis (group 2B); 23 patients with previous remote myocardial infarction and percutaneous coronary intervention (group 2C); and 21 patients with previous remote myocardial infarction but no percutaneous coronary intervention (group 2D). CFR in the LAD was not significantly different in groups 1 and 2 (3.08 +/- 0.61 and 3.03 +/- 0.69, respectively, p = NS). Decreased ejection fraction and increased wall motion score index in patients with remote CAD (p < 0.00001) and multivessel CAD did not affect CFR in the LAD (group 2A 3.18 +/- 0.77; group 2B 3.05 +/- 0.65; group 2C 3.07 +/- 0.79; group 2D 2.86 +/- 0.50, respectively; F = 0.63, p = NS). In conclusion, CFR of an angiographically normal LAD is preserved in patients with remote CAD, even in the presence of previous remote myocardial infarction and wall motion abnormalities.     

Obstructive sleep apnea as a risk marker in coronary artery disease

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is associated with a range of cardiovascular sequelae and increased cardiovascular mortality. The aim of our study was to assess the prevalence of OSA in patients with symptomatic angina and angiographically verified coronary artery disease (CAD). In addition, we analyzed the association of OSA and other coronary risk factors with CAD and myocardial infarction. METHODS: Overnight non-laboratory-monitoring-system recordings for detection of OSA was performed in 223 male patients with angiographically verified CAD and in 66 male patients with exclusion of CAD. A logistic regression analysis was performed to assess associations between risk factors and CAD and myocardial infarction. RESULTS: CAD patients were found to have OSA in 30.5%, whereas OSA was found in control subjects in 19.7%. The mean apnea/hypopnea index (AHI) was significantly higher (p < 0.01) in CAD patients (9.9 +/- 11.8) than in control subjects (6.7 +/- 7.3). Body-mass-index (BMI) was significantly higher in patients with CAD and OSA than in patients with CAD without OSA (28. 1 vs. 26.7 kg/m(2); p < 0.001). No significant difference was found with regard to other risk factors and left ventricular ejection fraction (LVEF) between both groups. Hyperlipidemia (OR 2.3; CI 1. 3-3.9; p < 0.005) and OSA defined as AHI >/=20 (OR 2.0; CI 1.0-3.8, p < 0.05) were independently associated with myocardial infarction. CONCLUSIONS: There is a high prevalence of OSA among patients with angiographically proven CAD. OSA of moderate severity (AHI >/=20) is independently associated with myocardial infarction. Thus, in the care of patients with CAD, particular vigilance for OSA is important.     

Assessments of left ventricular function during exercise in patients with dilated cardiomyopathy: comparison with ischemic cardiomyopathy

Responses to supine bicycle ergometer exercise were assessed in a study population consisting of 26 patients with dilated cardiomyopathy (DCM) and 23 patients with ischemic cardiomyopathy (ICM). Left ventricular ejection fraction (LVEF) and regional wall motion were analyzed at rest and during supine bicycle ergometer exercise with radionuclide ventriculography. Although the same degree of LVEF between DCM (23 +/- 8%) and ICM (26 +/- 4%) occurred at rest, the left ventricular regional wall motion abnormality was more prominent in DCM. LVEF during the peak exercise stage in DCM was almost unchanged (24 +/- 8%), but in ICM it decreased significantly (22 +/- 5%). Exercise-induced regional wall motion abnormalities were detected in nine patients (35%) in DCM and 13 patients (57%) in ICM. Although patients with DCM are believed to have diffuse hypokinesis of the left ventricle, severe regional wall motion abnormalities (akinesis or dyskinesis) were frequently observed. During the follow-up period of up to six years, eight patients with DCM died of congestive heart failure. In eight patients with DCM who showed decreased LVEF during exercise, five patients died. However, only three of 18 patients without decreased LVEF during exercise died. Exercise-induced left ventricular dysfunction in DCM seems to be a poor prognostic sign.     

Effect of exercise on left ventricular ejection fraction in men with coronary artery disease.

Left ventricular ejection fraction (LVEF) was measured at rest and during supine bicycle exercise in 31 men with arteriographically defined coronary disease and in 15 normal men. LVEF was calculated from a left ventricular time vs activity curve (collimated scintillation probe, 99m Technetium) as the fracitonal fall in count-rate divided by the background-corrected left ventricular end-diastolic count-rate. In normal men LVEF at rest averaged .59 +/- .06 (+/-SD) and during exercise was .72 +/- .08. LVEF did not increase with exercise in men with coronary disease (.55 +/- .03 to .57 +/- .03; N = 31; AVE +/-SEM; NS). In 17 men with coronary disease who had ST segment depression with exercise, LVEF either decreased or was unaltered in all (55 +/- .04 to .49 +/- .03; P less than 0.05); whereas in 14 without ST depression, LVEF increased in 10 (71 per cent) and was unaltered in 4 (29 per cent) (.54 +/- .04 to .66 +/- .04; P less than 0.01). Results suggest that LVEF during exercise normally increases, but in men with coronary disease LVEF either fails to increase or actually decreases. In addition there appears to be a relationship between ST segment changes during exercise and ejection fraction.     

Radionuclide angiographic assessment of global and segmental left ventricular function at rest and during exercise after coronary artery bypass graft surgery

Left ventricular ejection fraction (LVEF) was measured by radionuclide angiography at rest and during supine bicycle exercise before and 3 months after coronary artery bypass graft surgery (CABG) in 20 patients with chronic stable angina. The right anterior oblique gated first-pass technique was used to assess LVEF response to maximal exercise (Wmax), while the left anterior oblique equilibrium-gated technique was used to assess LVEF and relative LV volume changes during graded submaximal exercise. Mean LVEF was unchanged at rest after CABG by both the first-pass (60 +/- 12% vs 60 +/- 12%) and equilibrium-gated (61 +/- 13% vs 62 +/- 13%) measurements. At Wmax, mean first-pass LVEF was significantly higher postoperatively than preoperatively (63 +/- 17% vs 53 +/- 17%; p less than 0.01) with a higher Wmax (750 +/- 182 vs 590 +/- 202 kpm/min; p less than 0.001) and higher rate-pressure product (302 +/- 59 vs 222 +/- 57 units; p less than 0.001). Similarly, equilibrium-gated LVEF levels during graded exercise, using stepwise regression analysis, were significantly higher postoperatively than preoperatively (p less than 0.001); at the highest graded work load, they averaged 63 +/- 19% postoperatively and 53 +/- 17% preoperatively, with higher work loads (500 +/- 190 vs 417 +/- 155; p less than 0.05) and higher rate-pressure products (271 +/- 55 vs 207 +/- 53; p less than 0.001). The increase in exercise LVEF after surgery was due to a marked decrease in the ratio, relative to resting values, of counts-based end-systolic volumes during submaximal exercise (preoperatively 1.91 +/- 1.04; postoperatively 1.14 +/- 0.46; p less than 0.01). The five subjects in whom LVEF decreased significantly during exercise postoperatively all had one or more blocked or stenosed grafts. This study documents, by two independent radionuclide techniques, an improved LVEF during exercise at an increased maximal work capacity and rate-pressure product 3 months after successful CABG.     

Diagnostic value of the ratio of recovery systolic blood pressure to peak exercise systolic blood pressure for the detection of coronary artery disease

It has been previously reported that at treadmill exercise testing an abnormal ratio of recovery systolic blood pressure (SBP) to peak exercise SBP is more sensitive than exercise-induced angina or ST segment depression for diagnosing coronary artery disease (CAD). To investigate whether the SBP ratio keeps its diagnostic value during upright bicycle exercise, we evaluated the ratio of postexercise SBP to peak SBP in 73 patients with angiographically documented CAD and in 48 patients with normal coronary arteries (OV group) undergoing maximal stress testing on a bicycle ergometer. Three minutes after exercise ended, SBP ratio was significantly higher in the CAD than in the OV group (0.79 +/- 0.1 vs 0.71 +/- 0.08; p less than .001). Setting the upper normal limits of the recovery SBP ratio at 2 SDs from the mean for the OV group (SBP ratio = 0.98 and 0.88 at 1 and 3 min after exercise, respectively), with an increase or no change in SBP ratio at between 1 and 3 min of recovery considered an abnormal response, the sensitivity of SBP ratio was 30%, the specificity was 83%, and the accuracy was 51%. The respective values for ST depression were 81% (p less than .0001 vs SBP ratio), 48% (p less than .001 vs SBP ratio), and 67% (p less than .01 vs SBP ratio). Thus, for bicycle ergometer exercise testing, ST segment depression seems to be more accurate than SBP ratio in diagnosing CAD.     

Peak exercise and immediate postexercise imaging for the detection of left ventricular functional abnormalities in coronary artery disease

Eleven patients without significant coronary artery disease (CAD) (group A), 22 patients with significant CAD and no prior myocardial infarction (MI) (group B), and 10 patients with CAD and a previous MI (group C) were imaged at rest, at peak exercise and immediately after exercise by first-pass radionuclide angiography. At peak exercise, mean left ventricular (LV) ejection fraction (EF) did not change significantly in group A or C and decreased significantly in group B. However, in all groups mean LVEF increased significantly immediately after exercise. Examination of potential criteria for an abnormal LVEF response showed that changes from rest to peak exercise were sensitive for detection of CAD but were not specific. Postexercise criteria were more specific but relatively insensitive: 15 of 32 patients (47%) with CAD showed a normal (greater than 5% increase over rest) response after exercise. Similarly, a regional abnormality at peak exercise was 100% sensitive, compared with a sensitivity of 78% after exercise for the whole group, and only 68% in patients without prior MI. Seven patients would have been misclassified as normal if postexercise imaging alone had been performed. The likelihood of an abnormal postexercise EF response was related to the extent of CAD: No patient with 1-vessel, 8 of 17 with 2-vessel and 9 of 12 with 3-vessel CAD showed such a response. Peak exercise imaging is necessary to achieve maximal sensitivity for the detection of CAD, and a high false-negative rate will be obtained if postexercise imaging only is used. The combination of peak exercise and postexercise imaging may be of value in assessing the severity of CAD.     

Radionuclide assessment of left ventricular function during dobutamine infusion in patients with coronary artery disease: comparison with ergometer exercise

The effects of dobutamine on left ventricular function were assessed employing radionuclide ventriculography (RNV) in 7 normal subjects (Group 1) and 21 patients with coronary artery disease (Group 2). After routine bicycle ergometer exercise RNV, dobutamine infusion was started at 5 micrograms/kg/min and the dosage was increased by 5 micrograms/kg/min every 4 minutes to a total of 15 micrograms/kg/min. In Group 1, left ventricular ejection fraction (LVEF) increased by both ergometer exercise and dobutamine infusion. In Group 2, LVEF did not increase during exercise, but increased during dobutamine infusion without evidence of significant myocardial ischemia. Only 2 patients in Group 2 had new regional wall motion abnormality. Left ventricular end-diastolic volume (LVEDV) in Group 2 increased from 191 +/- 19 to 210 +/- 18 ml during ergometer exercise, but decreased from 193 +/- 18 to 153 +/- 19 ml during dobutamine infusion. Short-term low-dose infusion of dobutamine may be used in patients without evidence of significant myocardial ischemia, but probably cannot be substituted for exercise testing in patients with mild to moderate coronary artery disease.     

The effect of coronary artery bypass grafting on left ventricular systolic function at rest: evidence for preoperative subclinical myocardial ischemia

Successful coronary artery bypass grafting (CABG) improves exercise-induced left ventricular (LV) dysfunction in patients with coronary artery disease (CAD), but its potential for improving resting LV function remains controversial. To assess the influence of CABG on LV function at rest, 31 CAD patients without previous myocardial infarction were studied before and 6 months after CABG by radionuclide angiography after all cardiac medicines were withdrawn. No patient had angina or ischemic electrocardiographic changes at rest. In 27 patients with patent bypass grafts, CABG significantly increased LV ejection fraction during exercise (47 +/- 11% before to 63 +/- 9% after operation, p less than 0.001), indicating reduction in exercise-induced LV ischemia. Moreover, LV ejection fraction at rest also increased (55 +/- 9 to 60 +/- 8%, p less than 0.001), with 20 of 27 patients manifesting an increase compared with preoperative values. Eleven of these 20 patients had apparently normal LV function at rest (ejection fraction and regional wall motion) before CABG. LV regional ejection fraction was computed by dividing the LV region of interest into 20 sectors. Regional analysis indicated that improved ejection fraction at rest after CABG occurred in regions developing ischemia during exercise before CABG. In 4 patients with occluded grafts, the ejection fraction at rest was unchanged by CABG globally (59 +/- 8 to 58 +/- 9%, difference not significant) and regionally. Thus, LV global and regional function at rest improved after successful CABG, even in patients with normal global LV ejection fraction and no visually detectable wall motion abnormality before surgery.(ABSTRACT TRUNCATED AT 250 WORDS)     

Impact of diabetes mellitus on worsening of the left ventricular ejection fraction in exercise-gated 201Tl myocardial single photon emission computed tomography in patients with coronary artery disease.

It remains uncertain whether factors other than the severity of coronary artery disease (CAD) are associated with the worsening of the left ventricular ejection fraction (LVEF) by exercise. In the present study the impact of coronary risk factors on the worsening of LVEF by exercise was investigated in 391 patients with known or suspected CAD using exercise-gated (201)Tl scanning to calculate the LVEF. Significant worsening of the LVEF by exercise was defined as >4.7% (mean plus 1 SD of the value in 116 patients without CAD). Multivariate analysis revealed that diabetes mellitus (DM) was an independent risk factor for the worsening of LVEF by exercise in patients with multivessel (2- or 3-vessel) CAD with an odds ratio (95% confidence interval) of 2.2 (1.1-4.5, p=0.037). In 157 patients with 2- or 3-vessel CAD, 20 (23.5%) of 85 nondiabetic patients and 31 (43.1%, p=0.009 vs nondiabetic patients) of 72 diabetic patients showed significant worsening of LVEF by exercise. In patients with 2- or 3-vessel CAD, there was no significant difference in Gensini score or reversibility of perfusion defects between nondiabetic and diabetic patients. Thus, DM is a risk factor for worsening LVEF by exercise in addition to the severity of CAD.     

Relationship among pregnancy associated plasma protein-A levels, clinical characteristics, and coronary artery disease extent in patients with chronic stable angina pectoris.

AIMS: To assess, in chronic stable angina (CSA) patients, the relationship among clinical characteristics and cardiovascular risk factors, extent of coronary artery disease (CAD), and pregnancy-associated plasma protein-A (PAPP-A) levels. METHODS AND RESULTS: We studied 643 CSA patients (63+/-10 years, 482 men) undergoing diagnostic coronary angiography; 97 with angiographically normal coronary arteries or <50% stenosis, 127 with single vessel disease (VD), and 419 with multi-VD. Patients' age, gender, cardiovascular risk factors, body mass index, history of previous myocardial infarction, angina class, left ventricular ejection fraction (LVEF), and treatment were assessed at study entry. PAPP-A levels (mIU/L) were higher in men than in women (6.2+/-2.4 vs. 5.2+/-1.8; P<0.001) and in hypertensive vs. normotensive patients (6.4+/-2.8 vs. 5.8+/-2.1; P=0.01). PAPP-A correlated directly with age (r=0.19, P<0.001) and inversely with LVEF (r=-0.11, P=0.01). Patients with multivessel disease (VD) had higher PAPP-A levels (6.45+/-2.58) than those with single-VD (5.49+/-1.54, P<0.001) or normal coronaries (4.62+/-1.17, P<0.001). Male gender, age, history of a previous MI, hypercholesterolaemia, and PAPP-A levels were independent predictors for the presence of CAD. CONCLUSION: In CSA patients PAPP-A levels correlate with age, male gender, hypertension, and CAD extent. In the present study, PAPP-A was an independent predictor for the presence and extent of CAD.     

Noninvasive detection of multivessel disease after myocardial infarction by exercise radionuclide ventriculography

The ability of exercise radionuclide ventriculography to detect multivessel coronary artery disease in patients who survived a single myocardial infarction was assessed. Seventy-four patients who had had myocardial infarction at least 8 weeks earlier underwent cardiac catheterization and exercise radionuclide ventriculography. Thirty-eight patients had had an inferior infarction: 25 with multivessel disease and 13 with single vessel disease of the right coronary artery. Thirty-six patients had had an anterior infarction: 26 with multivessel disease and 10 with single vessel disease of the left anterior descending coronary artery.

Among patients with anterior infarction there was no significant difference between patients with single vessel disease and patients with multivessel disease with regard to resting ejection fraction, exercise ejection fraction, and the mean change from rest to exercise. Patients with single vessel disease had a decrease in ejection fraction from rest to exercise of 2.2 ± 2.7% units (mean) ± standard error [SE]), compared with a decrease of 5.4 ±1.3% units in those with multivessel disease (p = not significant [NS]). Seventeen of 26 (65%) patients with multivessel disease and 6 of 10 (60%) with single vessel disease had a decrease in ejection fraction of at least 5 percentage units (p = NS).

In patients with inferior infarction there was no difference in the mean resting ejection fraction in those with single vessel disease (53 ± 2%) compared with those with multivessel disease (50 ±2%); however, the mean exercise ejection fraction in patients with single vessel disease (57 ± 3%) was significantly higher (p < 0.005) than that in patients with multivessel disease (45 ± 2%). Sixteen of the 25 patients with multivessel disease (64%) but only 1 patient with single vessel disease (7.7%) had a decrease in ejection fraction of at least 5 percentage units (p < 0.001).

A new wall motion abnormality developed in 8 patients with anterior infarction and 11 with inferior infarction with multivessel disease and none with single vessel disease. The sensitivity and specificity in predicting multivessel disease using the criteria of the development of a new wall motion abnormality or a decrease in ejection fraction with exercise of at least 5 percentage units were 80 and 92% for the patients with inferior infarction, but only 69 and 40% for the patients with anterior infarction.

These results suggest that exercise radionuclide angiography can be used to discriminate between single and multivessel disease after inferior myocardial infarction. For patients with anterior infarction, only a new abnormality in wall motion accurately predicts multivessel disease, but this occurred in only one third of such patients.