Exercise-induced Abnormalities Research Articles

Comparisons of Increased Repetitions and Exercise Intensity of the Symmetric Upper Limbs between Men and Women

Background: Improperly conducted exercise may lead to worsening of musculoskeletal complications. Such may worsen due to increased repetition and intensity during exercise. In addition, different responses may show different needs for training program. Objectives: To compare kinematics of symmetric concentric and eccentric motions during increased repetitions and intensities for men and women. Design: Quasi-randomized trial. Methods: A total of ten men and eleven women participated in this study. Concentric and eccentric motions of the lateral raises were observed for initial positions of abduction and adduction. Low and high exercise intensities were applied, and 15 repetitions were conducted for both intensities. Initial, 3 inbetween repetitions, and last repetition were recorded for comparisons. Results: The concentric or abduction motions showed no significant differences for all comparisons. However, eccentric or adduction motions showed greater significant differences as the exercise intensity increased for both men and women. Such significant differences were most prevalent during the first and last repetitions with greatest differences during the initial repetitions. Conclusion: Kinematic difference between men and women during increased repetitions and intensity indicate the need for more individualized exercise intervention and consideration between men and women. Individualized interventions may prevent exercise-induced postural abnormality and corresponding musculoskeletal dysfunction.

Determining Safe Participation in Aerobic Exercise Early After Stroke Through a Graded Submaximal Exercise Test.

The benefits of aerobic exercise early after stroke are well known, but concerns about cardiovascular risk are a barrier to clinical implementation. Symptom-limited exercise testing with electrocardiography (ECG) is recommended but not always feasible. The purpose of this study was to determine the frequency of and corresponding exercise intensities at which ECG abnormalities occurred during submaximal exercise testing that would limit safe exercise prescription beyond those intensities. This study was a retrospective analysis of ECGs from 195 patients who completed submaximal exercise testing during stroke rehabilitation. A graded submaximal exercise test was conducted with a 5- or 12-lead ECG and was terminated on the basis of predetermined endpoint criteria (heart rate, perceived exertion, signs, or symptoms). ECGs were retrospectively reviewed for exercise-induced abnormalities and their associated heart rates. The peak heart rate achieved was 65.4% (SD=10.5%) of the predicted maximum heart rate or 29.1% (SD=15.5%) of the heart rate reserve (adjusted for beta-blocker medications). The test was terminated more often because of perceived exertion (93/195) than because of heart rate limits (60/195). Four patients (2.1%) exhibited exercise-induced horizontal or downsloping ST segment depression of ≥1mm. Except for 1 patient, the heart rate at test termination was comparable with the heart rate associated with the onset of the ECG abnormality. A graded submaximal exercise test without ECG but with symptom monitoring and conservative heart rate and perceived exertion endpoints may facilitate safe exercise intensities early after stroke. Symptom-limited exercise testing with ECG is still recommended when progressing to higher intensity exercise. Concerns about cardiovascular risk are a barrier to physical therapists implementing aerobic exercise in stroke rehabilitation. This study showed that, in the absence of access to exercise testing with ECG, submaximal testing with conservative heart rate and perceived exertion endpoints and symptom monitoring can support physical therapists in the safe prescription of aerobic exercise early after stroke. It is recommended that people with stroke participate in aerobic exercise as early as possible during their rehabilitation. A submaximal exercise test with monitoring of heart rate, perceived exertion, blood pressure, and symptoms can support physical therapists in safely prescribing that exercise.

4252Additional value of stress testing for evaluation of ventricular arrhythmias in athletes undergoing preparticipation screening

Abstract Introduction The optimal protocol of athletes pre-participation screening is a matter of debate. The aim of this study is to test the additional value of exercise testing (ET) for evaluation of ventricular arrhythmias (VA) in athletes with otherwise normal findings. Methods The study included 10,975 competitive athletes who underwent preparticipation screening including ECG and stress testing. Athletes with ≥3 isolated premature ventricular beats or ≥1 repetitive VA underwent second-line investigations (echocardiography and 24-hour ambulatory ECG monitoring with a training session) and, in case of frequent, complex or exercise-induced VA or echocardiographic abnormalities, also cardiac magnetic resonance (CMR). Results 451 (4,1%) athletes were excluded for abnormalities at history, physical examination and baseline ECG. Among the remaining 10524 athletes, 524 (5%)showed VA at ET, 87 of whom underwent CMR.Echocardiography identified major cardiac abnormalities in 5 athletes and regional ventricular systolic dysfunction in 7, which were confirmed by CMR in 6. Other 12 patients with normal echocardiography had a positive CMR. In particular, in 16 subjects the CMR showed left ventricular late gadolinium enhancement suggesting myocardial fibrosis with a non-ischemic distribution. At multivariate analysis, VA observed at high work load at ET, the presence of complex VA at ET and the presence of a morphology other than infundibular or fascicular predicted an underlying pathological myocardial substrate while the presence of frequent (>500/24-hour) premature ventricular beats did not. Predictors of underlying pathological myocardial substrate Substrate Univariate Multivariable YES (n=23) NO (n=501) OR (95% IC) P OR (95% IC) P Age 17 [13–43] 15 [14–17] 1.03 [0.98 -1.06] 0.18 – Male gender 15 (65%) 184 (37%) 3.2 [1.3–7.7] <0.001 1.6 [0.7–4.8] 0.28 >500 PVBs/24-hour 7 (30%) 98 (20%) 1.8 [0.7–4.5] 0.21 – VA at high work-load 10 (44%) 78 (16%) 4.2 [1.8–9.8] <0.001 1.6 [1.1–4.7] 0.02 Couplets/NSVT at ET 14 (61%) 117 (23%) 6.2 [2.5–15] <0.001 8.5 [2.5–29] 0.01 PVBs other than infundibular/fascicular 17 (74%) 118 (24%) 6.1 [2.4–16] <0.001 3.9 [1.4–11] 0.008 Conclusions VA at ET may represent the only sign of a pathological myocardial abnormalities, such as the “isolated nonischemic left ventricular scar”, that could be the substrate for life-threatening ventricular arrhythmias. Addition of ET to baseline ECG may increase the sensitivity of PPE of competitive athletes.

Increased sensitivity of prolonged P-wave during exercise stress test in detection of angiographically documented coronary artery disease.

A retrospective study was designed to investigate P-wave duration changes in exercise stress test (EST) for the prediction of angiographically documented substantial coronary artery disease (CAD). We analyzed 265 cases of patients, who underwent EST and subsequently coronary angiography. Analysis of P-wave duration was performed in leads II, V5 at rest, and in the recovery period. The sensitivity and specificity for the isolated ST-segment depression were only 31% and 76%, respectively. The combination of ST-depression with other exercise-induced clinical and electrocardio-graphic abnormalities (chest pain, ventricular arrhythmia, hypotension, left bundle branch block) was characterized by 41% sensitivity and 69% specificity. The combination of abnormal recovery P-wave duration (≥ 120 ms) with ST-depression and other exercise-induced abnormalities had 83% sensitivity but only 20% specificity. Combined analysis of increased delta P-wave duration, ST-depression and other exercise-induced abnormalities had 69% sensitivity and 42% specificity. Sensitivity and specificity of the increase in delta P-wave duration for left CAD was 69% and 47%, respectively, and for 3-vessel CAD 70% and 50%, respectively. The presence of arterial hypertension negatively influenced the prog-nostic value of P-wave changes in the stress test. The results of the study show that an addition of P-wave duration changes assessment to ST-depression analysis and other exercise-induced abnormalities increase sensitivity of EST, especially for left CAD and 3-vessel coronary disease. We have also provided evidence for the negative influence of the presence of arterial hypertension on the predictive value of P-wave changes in the stress test. (Cardiol J 2017; 24, 2: 159-166).

The role of exercise echocardiography in the diagnostics of heart failure with normal left ventricular ejection fraction

Few data are available on the exercise-induced abnormalities of myocardial function in patients with exertional dyspnoea and normal left ventricular ejection fraction (LV EF). The main aims of this study were to determine the prevalence of isolated exercise-induced heart failure with normal ejection fraction (HFNEF) and to assess whether disturbances in LV or right ventricular longitudinal systolic function are associated with the diagnosis of HFNEF. Eighty-four patients with exertional dyspnoea and normal LV EF and 14 healthy controls underwent spirometry, NT-proBNP plasma analysis, and exercise echocardiography. Doppler LV inflow and tissue mitral and tricuspid annular velocities were analysed at rest and immediately after the termination of exercise. Of the 30 patients with the evidence of HFNEF, 6 (20%) patients had only isolated exercise-induced HFNEF. When compared with the remaining patients, those with HFNEF had a significantly lower resting and exercise peak mitral annular systolic velocity (Sa) and the mitral annular velocity during atrial contraction, lower exercise peak mitral annular velocity at early diastole, and lower exercise peak systolic velocity of tricuspid annular motion. The multivariate logistic regression analysis including both parameters standardly defining HFNEF and the new Doppler variables potentially associated with the diagnosis of HFNEF revealed that NT-proBNP, LV mass index, left atrial volume index, and Sa significantly and independently predict the diagnosis of HFNEF. A significant proportion of patients require exercise to diagnose HFNEF. Sa appears to be a significant independent predictor of HFNEF, which may increase the diagnostic value of models utilizing the variables recommended by the European Society of Cardiology guidelines.

Idiopathic pulmonary fibrosis‐related pulmonary hypertension; an exercising diagnosis?

Idiopathic pulmonary fibrosis‐related pulmonary hypertension; an exercising diagnosis?

The diastolic stress test: a new approach to an old problem

The evaluation of ischemic heart disease is the cornerstone of clinical Cardiology. Although there are many means of ischemic evaluation, all are with their own limitations. While perfusion-based studies are highly sensitive, they lack specificity. Conversely, systolic wall motion analysis with echocardiography tends to have high specificity; however, the sensitivity may be limited by short duration of systolic abnormalities when present. With the advent of Doppler echocardiography, and more specifically tissue Doppler imaging, and strain and strain rate imaging, a more comprehensive evaluation of the left ventricular function is available, including diastole. Diastolic abnormalities in the setting of ischemia are now being studied using these new parameters and have been suggested as a reliable marker of ischemia. Exercise-induced abnormalities in diastolic parameters have improved sensitivities and specificities over traditional stress testing and persist longer than systolic abnormalities. A review of the medical literature regarding the subject will be discussed here.

Loss of diastolic time as a mechanism of exercise-induced diastolic dysfunction in dilated cardiomyopathy

Cardiac performance can be characterized in terms of the relative duration of left ventricular systole and diastole. Little is known about exercise-induced abnormalities of the systolic-diastolic phase proportion and its impact on hemodynamic variables in patients with idiopathic dilated cardiomyopathy (IDCM). The phases of the cardiac cycle were derived with high temporal resolution from the left ventricular time-activity curve simultaneous with hemodynamic measurements. In patients with IDCM, the loss of diastolic time (LDT) per beat was quantified using a regression equation obtained from a healthy control group (n = 26). According to the median LDT at peak exercise, patients were divided into 2 subgroups: subgroup A with an LDT <or=22 milliseconds (n = 28) and subgroup B with an LDT >22 milliseconds (n = 27). The relative duration of left ventricular systole was increased in patients with IDCM during peak exercise compared to healthy subjects (29.3 vs 26.7 s/min, P < .02). This abnormality translated into a significant LDT when observed, and predicted values of diastolic time were compared. Subgroup B patients had a higher increment in mean pulmonary capillary wedge pressure but a smaller increase in stroke volume index from rest to peak exercise (14.3 vs 8.6 mm Hg [P = .007] and 12.5 vs 7.2 mL/m(2) [P = .04]) compared to subgroup A patients. An abnormal shortening of diastolic time during exercise can restrict left ventricular filling to an extent that is sufficient to limit left ventricular stroke volume reserve and to cause pulmonary congestion.

Role of nondiagnostic exercise-induced ST-segment abnormalities in predicting future coronary events in asymptomatic volunteers

Role of nondiagnostic exercise-induced ST-segment abnormalities in predicting future coronary events in asymptomatic volunteers

Infection by CagA-positive Helicobacter pylori strains in patients with ischemic heart disease: prevalence and association with exercise-induced electrocardiographic abnormalities.

The role of H. pylori infection in increasing the risk of ischemic heart diseases (IHD) is still debated. We determined serologically the prevalence of overall H. pylori and CagA-positive H. pylori infection in 63 consecutive patients with IHD and 189 gender- and age-matched controls. We also determined in patients the influence of the infection and the CagA serological status on the results of an exercise ECG test and other parameters considered possible variables that may enhance the risk of IHD. The prevalence of H. pylori infection in patients and controls was 79.3% and 73.0%, respectively (P = 0.403) and that of CagA-positive H. pylori infection was 69.8% and 42.3%, respectively (P = 0.0002). The scores of the ECG S-T segment and T-wave abnormalities in the course of an exercise ECG in uninfected patients and in patients infected by CagA-negative and CagA-positive H. pylori strains were (mean +/- SD): 1.59 +/- 0.67, 1.92 +/- 0.64, and 2.19 +/- 0.70, respectively; (P = 0.011, 95% confidence limits of difference 0.15-1.07, CagA-positive infected vs uninfected patients). There was no intergroup difference in the levels of peripheral white blood cells, glucose, cholesterol, triglycerides, creatinine, and systolic and diastolic pressure. In conclusion, genetic heterogeneity of H. pylori could possibly explain some conflicting results concerning the association of H. pylori infection with IHD. Coronary vessels of IHD patients infected by CagA-positive H. pylori strains may be damaged more severely than those of uninfected patients.

Exercise echocardiography for the prognostic stratification of patients with low pretest probability of coronary artery disease

PURPOSE: The aim of this study was to determine whether exercise echocardiography provides incremental data for risk stratification of patients with a low pretest probability of coronary artery disease. PATIENTS AND METHODS: The study included patients referred for exercise echocardiography whose probability of coronary artery disease was 25% or less. We calculated an exercise wall motion score index (on a 1–5 scale), an indicator of the extent and severity of exercise-induced abnormalities. The primary outcomes of the study were subsequent cardiac events (cardiac death and nonfatal myocardial infarction). RESULTS: We studied 571 men and 1047 women; their mean (± SD) age was 55 ± 13 years. During a median follow-up of 3 years, there were 19 cardiac events (6 cardiac deaths and 13 nonfatal myocardial infarctions); an additional 37 patients underwent coronary revascularization. In a multivariate analysis of clinical, exercise electrocardiographic, and echocardiographic parameters, exercise wall motion score index (hazard ratio [HR] = 2.1 per 0.5 units; 95% confidence interval [CI]: 1.3 to 3.4), and age (HR = 2.0 per decade; 95% CI: 1.2–2.8) were independently associated with the risk of cardiac events. Although exercise echocardiographic variables contributed significantly ( P = 0.01) to a model of the risk of adverse events, only 9 (47%) of the 19 patients with cardiac events were identified by an abnormal exercise echocardiogram. CONCLUSION: Among patients with low pretest probability of coronary artery disease by clinical criteria, exercise echocardiography identifies some, but not all, patients at risk of future events. Because of the low event rate, routine application of exercise echocardiography in a patient with a low pretest probability does not appear to be cost-effective and therefore cannot be recommended.

QT dispersion in patients with Takayasu arteritis.

This study was designed to test the hypothesis that myocardial involvement exists in patients with Takayasu arteritis and is associated with increased QT dispersion, which is a marker of repolarization inhomogeneity. Twenty-one consecutive patients with Takayasu arteritis and no significant coronary artery disease were included. Twelve-lead electrocardiogram and exercise-induced thallium-201 myocardial scintigraphy were performed in all patients. Ten of 21 patients (48%) had abnormal findings on scintigraphy. Patients were divided into two groups by the presence (group P, n = 10) or absence (group N, n = 11) of exercise-induced thallium-201 myocardial scintigraphic perfusion abnormalities, including permanent defects in three, reversible defects in four, and slow washout in three. The QT dispersion at rest was significantly greater in group P than that in group N (54 +/- 12 vs 40 +/- 8 msec, p < 0.005). The QTc dispersion at rest was also significantly greater in group P than in group N (59 +/- 15 vs 43 +/- 11 msec, p < 0.01). In patients with Takayasu arteritis, myocardial involvement suggested by exercise-induced thallium-201 myocardial scintigraphic perfusion abnormalities is not rare, even when no significant coronary stenosis is present on angiography. Increased baseline QT dispersion was associated with scintigraphic abnormalities and may be a useful marker of myocardial involvement in patients with Takayasu arteritis.

Relation between exercise-induced ventricular arrhythmias and myocardial perfusion abnormalities in patients with intermediate pretest probability of coronary artery disease.

The significance of exercise-induced ventricular arrhythmias (VAs) is largely dependent on the clinical characteristics of the studied population. The relation between exercise-induced VAs and myocardial perfusion abnormalities has not yet been evaluated in a homogeneous patient population with intermediate probability of coronary artery disease (CAD). We studied 302 patients (mean age 54+/-9 years, 152 men and 150 women) with intermediate pretest probability of CAD (range=0.25-0.80, mean=0.43+/-0.20) by upright bicycle exercise stress test in conjunction with technetium-99m single-photon emission tomography (SPET) imaging. Exercise-induced VAs (frequent or complex premature ventricular contractions or ventricular tachycardia) occurred in 65 patients (22%). No significant difference was found between patients with and patient without VAs regarding the pretest probability of CAD (0.45+/-0.21 vs 0.43+/-0.20). Patients with exercise-induced VAs had a higher prevalence of perfusion abnormalities (52% vs 26%, P=0.002) and ischaemic electrocardiographic changes (31% vs 16%, P<0.05) compared to patients without VAs. A higher prevalence of perfusion abnormalities in patients with VAs was observed in both men (67% vs 35%, P<0.01) and women (38% vs 16%, P<0.05). However, the positive predictive value of exercise-induced VAs for the presence of myocardial perfusion abnormalities was higher in men than in women (67% vs 38%, P<0.05). The presence of abnormal myocardial perfusion was the only independent predictor of exercise-induced VAs (OR 2.2; 95% CI, 1.2-4.2) by multivariate analysis of clinical and stress test variables. It is concluded that in patients with intermediate pretest probability of CAD, exercise-induced VAs are predictive of a higher prevalence of myocardial perfusion abnormalities in both men and women. However, the positive predictive value of exercise-induced VAs for perfusion abnormalities is higher in men. Because of the underestimation of ischaemia by electrocardiographic changes, exercise-induced VAs should be interpreted as a marker of a higher probability of CAD.

Patterns of diastolic abnormalities during isometric stress in patients with systemic hypertension.

This study was undertaken to determine the prevalence and distribution of diastolic function abnormalities at rest and during isometric exercise in patients with systemic hypertension using the recently introduced handgrip-apexcardiographic test (HAT). It has been shown that HAT reflects left ventricular pressure changes in early (relaxation) and late (compliance) diastole. A HAT was obtained in 132 patients with systemic hypertension (duration >1 year) without history of congestive heart failure. A healthy group (n = 186) served as control subjects. Diastolic abnormalities were present at rest in 53/132 (40%) and during isometric handgrip stress in 92/132 (70%) patients. At rest the most frequent diastolic abnormality was the prolongation of relaxation time (27%) whereas an isolated increase in A wave was rare (8%). During isometric exercise, however, an elevation of A wave was the predominant abnormality (38%) whereas an isolated prolongation of relaxation time was less frequent (14%). Alternatively, an 'ischemic' pattern (abnormal prolongation of resting normal relaxation time during handgrip and/or abnormal as well as more than double increase of resting normal relative A wave to total height during or after handgrip) was observed in 29%. In 89% of these patients with an ischemic pattern of diastolic changes, a typical angina and/or positive stress ECG and/or angiographically proved coronary artery disease were present. Using HAT data the present study demonstrates for the first time that in patients with systemic hypertension: (1) diastolic abnormalities occur significantly more frequently during isometric stress than at rest, (2) the most frequently observed diastolic abnormality at rest is the relaxation time prolongation whereas during isometric stress the A wave elevation, and (3) patients with an ischemic pattern of exercise-induced diastolic abnormalities show frequently clinical or angiographic evidence of demand ischemia. Thus, HAT can become a useful additional diagnostic tool for detecting latent diastolic dysfunction and myocardial ischemia in this clinical setting.

Ischemic and Nonischemic Patterns of Diastolic Abnormalities during Isometric Handgrip Exercise

This study establishes the clinical value of the recently introduced handgrip-apexcardiographic test (HAT) as an additional tool for distinguishing exercise-induced diastolic abnormalities in coronary artery disease (CAD) patients from those in patients with hypertrophic cardiomyopathy (HCM). This stress test reliably assessing differences in diastolic indices during handgrip between 305 healthy volunteers and 39 patients with CAD without prior infarction as well as 17 patients with HCM showed two different patterns of handgrip-induced pathological changes in these indices. An 'ischemic diastolic response' was empirically defined by the presence of either a handgrip-induced more than doubling of a resting normal relative A wave to total height of the apex-cardiogram (ischemic compliance response) or a pathological prolongation of a resting normal total apexcardiographic relaxation time (ischemic relaxation response); whereas a 'nonischemic diastolic response' was defined by the presence of a positive HAT and by absence of the above-mentioned ischemic criteria. An ischemic pattern of diastolic abnormalities was present in 72% of CAD patients, whereas 94% of HCM patients showed a 'nonischemic' diastolic response. These results confirm that in CAD patients there is a typical response of diastolic apexcardiographic indices to isometric stress and, therefore, this simple stress test could be potentially useful in separating these patients from those with nonischemic myocardial disease states.

Clinical Value of Types of Exercise-Induced Diastolic Abnormalities in Patients with Myocardial Disease

Clinical Value of Types of Exercise-Induced Diastolic Abnormalities in Patients with Myocardial Disease

Exercise-induced diastolic abnormalities assessed by handgrip-apexcardiographic test in syndrome X.

It has been shown recently that the handgrip-apexcardiographic test (HAT) represents a new mode of stress test, which shows a high sensitivity in identifying coronary patients by assessing exercise-induced ischemic left ventricular diastolic abnormalities. To assess the prevalence of left ventricular diastolic abnormalities and the usefulness of HAT as a diagnostic tool in patients with syndrome X (angina pectoris in the presence of normal coronary arteries), HAT was obtained in 275 clinically normal subjects and in 9 patients who presented with typical chest pain and who were subsequently found to have a positive treadmill ECG test and no coronary artery disease by angiography. As diastolic indices served: the relative A wave to total height (A/H) and to diastolic amplitude (A/D) of the apex tracing, the total apexcardiographic relaxation time (TART), TART corrected for the duration of diastole (TARTI) and the diastolic amplitude time index [DATI = TARTI/(A/D)]. Positivity of HAT was defined by the presence of at least one of the following recently introduced criteria: (1) A/H during or after handgrip > 21%, (2) TART during handgrip > TART at rest > 143 ms or/and TARTI during handgrip < 0.14 or (3) DATI during handgrip < 0.27. At rest, in 6/9 (67%) patients all variables were within normal limits, whereas in 3/9 (33%) patients an abnormal A/H or TARTI was observed. During and after handgrip, however, all patients showed abnormal changes in at least two diastolic variables, DATI and A/H being most frequently abnormal (67 and 56%, respectively). Further, using the above-mentioned positivity criteria, all patients had a positive HAT result.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise-induced Wall Motion Abnormalities and Resting Left Ventricular Dysfunction in the Morbidly Obese as Assessed by Radionuclide Ventriculography.

Rest and exercise first pass radionuclide ventriculograms were obtained in 62 morbidly obese subjects (56 women, six men, mean age 38 years, mean weight 269.2 +/- 46.0 lb, mean height 65.2 +/- 3.1 in., mean Body Mass Index 44.5 +/- 6.2 kg/m(2), mean excess body weight 134.1 +/- 41.1 lb) scheduled for vertical banded gastroplasty. Fifty-six percent demonstrated exercise-induced wall motion abnormalities mimicking coronary disease, compared to 12% of controls (p = 0.03). No subject with exercise-induced abnormalities had coronary disease at cardiac catheterization although only those with an anginal chest pain history underwent angiography. Twenty-six percent demonstrated resting left ventricular systolic dysfunction as manifested by a reduced resting left ventricular ejection fraction ( <0.50). Thirty-one percent of these patients demonstrated exercise-induced abnormalities, versus 65% of morbidly obese subjects with normal resting ejection fractions (p = 0.04). Obesity-induced left ventricular hypertrophy with associated reduced coronary vasodilator reserve could explain the abnormalities. Six month post-gastroplasty follow-up radionuclide ventriculograms show group normalization of the resting left ventricular ejection fraction in those with preoperative dysfunction, possibly due to left ventricular unloading with some regression of hypertrophy.

Transient Myocardial Perfusion Abnormalities in Diabetic Patients: A Prospective Study Using Thallium Exercise Tolerance Testing

To determine whether diabetic patients without known cardiovascular disease have exercise-induced perfusion abnormalities without symptoms, we performed thallium-201 exercise tolerance testing (ETT) on 16 subjects with diabetes mellitus (8 men and 8 women; mean age = 51 +/- 2 years). To compare these patients to another group at risk for coronary disease and painless myocardial infarction, 13 hypertensive (7 men and 6 women; mean age = 50 +/- 2 years) patients without symptoms of atherosclerotic disease served as controls. Diabetic and hypertensive patients were similar with regard to age, sex, years since diagnosis and other cardiac risk factors. Abnormal exercise thallium testing was more common among diabetic patients (11/16 = 69%; p less than 0.05) as compared to hypertensive patients (4/13 = 31%). None of the patients reported chest pain or its equivalent. There was no difference between diabetic and hypertensive subjects in the number of minutes exercised, percentage of maximal heart rate attained or final heart rate achieved. Diabetic subjects as a group had greater evidence of peripheral neuropathy but no abnormality of autonomic nerve function. Using ETT with thallium scintigraphy, diabetic patients without known cardiovascular disease were more likely to have transient myocardial perfusion defects than were hypertensive patients.

The divergent recovery of ST-segment depression and radionuclide angiographic indicators of myocardial ischemia

This study evaluated the recovery after exercise of both ST-segment depression on the exercise electrocardiogram (electrical evidence of ischemia) and exercise-induced abnormalities in wall motion or ejection fraction as detected by radionuclide angiography. The study group of 31 patients was selected to undergo prolonged etectrocardiographic and radionuclide imaging after exercise because they had persistent ST-segment depression >3 minutes after exercise and radionuclide angiographic evidence of ischemia at peak exercise. In 27 (87%) of the 31 patients, radionuclide evidence of ischemia recovered more quickly than the electrocardiogram. Only 15 of the 31 patients had exercise-induced radionuclide abnormalities after exercise. Compared with the 16 patients without such findings of ischemia after exercise, these 15 patients had a worse wall motion score at peak exercise (5.3 vs 3.9; p < 0.01) and a smaller increase in systolic blood pressure with exercise (p < 0.05) and after exercise (p < 0.01). Radionuclide angiographic evidence of ischemia recovers more quickly after exercise than ST-segment depression. When there is radionuclide evidence of ischemia after exercise, it is associated with more severe ischemia during exercise.