Exercise Left Ventricular Ejection Fraction Research Articles

Twelve-year outcome of patients with an abnormal exercise radionuclide left ventricular angiogram and angiographically insignificant coronary artery disease

This study examines the long-term prognosis of patients with an abnormal exercise radionuclide angiogram in the absence of significant angiographic coronary artery disease (CAD). In general, patients without significant CAD have an excellent prognosis, but the long-term outcome for the subset of patients with an “ischemic” exercise test is not known. In this study, 161 patients with normal coronary arteries or insignificant CAD (<50% left main and <70% left anterior descending, left circumflex, or right), resting left ventricular (LV) ejection fraction ≥0.50, and an abnormal exercise radionuclide angiogram (LV ejection fraction that decreased with exercise or peak exercise LV ejection fraction <0.60) were followed for a median duration of 11.3 years. The mean Δ LV ejection fraction was −0.07, 98 patients (61%) had a decrease in LV ejection fraction of ≥5 units, and 40 patients (25%) had peak exercise LV ejection fraction <0.50. During follow-up there were 19 deaths (only 1 of which was cardiac), 7 nonfatal myocardial infarctions, and 9 revascularization procedures. At 12 years, overall survival was 88%, better than the expected survival for the age- and sex-matched general population. Survival free of cardiac death or myocardial infarction was 94% and survival free of any cardiac event including revascularization was 88%. Thus, patients with an abnormal exercise radionuclide angiogram but without significant CAD have an excellent long-term prognosis.

Relation Between Exercise-Induced Left Ventricular Wall Motion Abnormalities and Coronary Artery Disease in Hypertensive Patients Effects of Blood Pressure Normalization

In hypertension, several factors disturb coronary circulation and the metabolic reserve of the heart. This study was undertaken to test whether in hypertensive patients global and regional left ventricular (LV) function is related during exercise to the presence of significant coronary stenosis and whether lowering of coronary perfusion pressure through rapid normalization of the diastolic pressure may modify the dynamics of the left ventricle. Thirty-five patients with mild to moderate hypertension undergoing coronary angiography for the evaluation of chest pain were included in the study; upright bicycle exercise echocardiography tests were performed without therapy and 1 day later 1 h after sublingual administration of nifedipine. LV ejection fraction and regional wall motion scores were evaluated and compared at baseline, peak exercise, immediate postexercise, and recovery phases in each test through digital on-line storing of echocardiographic images. Twenty-one patients had normal coronary arteries (group 1) and 14 significant coronary stenoses (group 2); age, gender, heart rate, blood pressure, left ventricular diameter and mass index, and ejection fraction were similar in the two groups. At peak exercise LV ejection fraction slightly increased in group 1, whereas it slightly decreased in group 2 (both during the test without therapy and after nifedipine administration). All patients in group 1 had normal left ventricular wall motion during exercise; 13 of 14 patients in group 2 had LV wall motion abnormalities at peak exercise. Nifedipine did not produce any effect on LV regional wall motion in group 1, but it induced significant changes in LV regional wall motion in seven patients in group 2. Changes in LV wall motion between the two test groups were related to the number of the stenotic coronary vessels: the normal exercise test before and after therapy and the two normalized tests after nifedipine administration were in fact observed in patients with one-vessel disease, whereas worsening or changes in the site of ischemia were observed only in patients with multivessel disease. Regional and global left ventricular dynamics during exercise is mainly dependent on the existence of significant coronary artery disease. Rapid decrease of blood pressure does not alter the regional dynamics of the left ventricle during exercise in patients without coronary artery disease, but it may induce normalization, worsening, or changes in the site of wall motion abnormalities in hypertensives with significant coronary stenoses.

Metoprolol Abolishes Exercise-Induced Left Ventricular Dysfunction in Patients With Silent Ischemia

Left ventricular systolic function is reduced during episodes of silent ischemia in patients with coronary artery disease (CAD). Left ventricular ejection fraction (LVEF) is increased at least 5 absolute percent during exercise in most normal subjects; however, in patients with CAD, LVEF often remains unchanged or decreases. The anti-ischemic effect of β-adrenergic receptor blockade is well documented, including a reduction of exercise-induced electrocardiographic ST depressions; however, the effect of these drugs on left ventricular volume changes during exercise in patients with silent ischemia is unknown. The aim of this study was to evaluate the effect of a cardio-selective β-blocking agent, metoprolol, on rest and exercise LVEF in patients with silent ischemia, using radio-nuclide cardiography. Fifteen patients with silent ischemia completed a double-blind, placebo-controlled crossover study at rest and during submaximal exercise. LVEF remained unchanged during exercise in the placebo phase (56% to 58%; p = NS), but even though LVEF tended to decrease 56% during rest after metoprolol versus 52% after placebo (p = NS), the LVEF increase from rest to exercise resembled a normal LVEF response, 52% to 58% (p = 0.005). Exercise-induced electrocardiographic ST depressions were also reduced during metoprolol treatment. In patients with silent ischemia, the exercise-induced change in LVEF rises significantly during metoprolol treatment. The mechanism may be a reduction in myocardial ischemia as indicated by a reduction in ischemic electrocardiographic findings. (Am J Cardiol 1996;78:871–875)

Review of tests for monitoring doxorubicin-induced cardiomyopathy.

The objective of this review is to make physicians aware of new radionuclide methods to detect cardiac effects of chemotherapeutic drugs. This knowledge is important because of the limitations of the physical examination and the electrocardiogram for detecting early reversible cardiac damage. Presently left ventricular ejection fraction (LVEF) is routinely used to screen for cardiotoxicity. Since LVEF obtained by radionuclide angiocardiography is more accurate than the LVEF estimated by echocardiography, serial radionuclide LVEF monitoring is most commonly used to monitor cardiotoxicity. Diastolic measurements of left ventricular function (such as peak filling rate) are now being added to routine LVEF measurements to enhance standard radionuclide evaluation. This screening test should be done prior to beginning therapy and at appropriate points based on the baseline study, therapy scheme and the patient's clinical status. At some centers, exercise LVEF methods are being used to determine if cardiac reserve is adequate for the patient to tolerate additional chemotherapy when cardiac injury may be present. Previously, endomyocardial biopsy was needed to detect and confirm early anthracycline cardiotoxicity. This invasive test may be replaced by a new noninvasive in vivo method using radioactive monoclonal antibodies against cardiac muscle (indium-111-antimyosin). Because cardiac failure has been associated with adrenergic neuron injury, it has been proposed that radioactive methyliodobenzylguanine may detect the adrenergic abnormality which may predict future development of congestive heart failure or sudden death months after therapy is discontinued. Advantages and disadvantages of these methods in evaluating cardiotoxicity, and an algorithm to optimally monitor antitumor therapy-induced cardiomyopathy are discussed.

Repeatability of treadmill exercise ejection fraction and wall motion using technetium 99m-labeled sestamibi first-pass radionuclide ventriculography.

Peak treadmill exercise radionuclide ventriculography (RVG) with technetium 99m has recently been validated for determination of left ventricular ejection fraction (LVEF). However, the repeatability of this technique for determination of both LVEF and regional wall motion has not been reported. Each of 27 clinically stable patients underwent two treadmill exercise RVG studies within 40 +/- 51 days. The level of exercise achieved in the two tests was similar (double product: 26,357 +/- 3877 vs 26,621 +/- 4287), and there was no change in clinical or treatment status between the studies. Acquisition and processing were accomplished with a mobile multicrystal camera and a new version of a commercial software (Scinticor SIM 400 V. 4.1 BETA, Milwaukee, Wis.) that uses two left ventricular regions of interest. The two tests were compared to assess agreement (repeatability) on both an automatically calculated LVEF and wall motion in five left ventricular segments (basal anterior, distal anterior, apical, distal inferior, and basal inferior), with a 3-point semiquantitative visual score. Intraobserver and interobserver agreements (reproducibility) also were assessed on quantitative exercise LVEF derived from the same RVG test from a separate group of 20 patients with a broad range of exercise LVEF. The first and second treadmill exercise LVEFs were highly correlated (r = 0.92, SEE = 3.96, y = 0.97x + 0.58; and r = 0.99, SEE = 1.32, y = 0.99x + 0.25, respectively). Results of segmental visual score agreement between the first and the second treadmill first-pass studies were as follows: overall, 86% (116/135, kappa = 0.74); basal anterior, 85% (23/27, kappa = 0.72); distal anterior, 85% (23/27, kappa = 0.84); apical, 93% (25/27, kappa = 0.85); distal inferior, 93% (25/27, kappa = 0.80); and basal inferior, 67% (18/27, kappa = 0.64). Treadmill exercise first-pass RVG is a highly repeatable and reproducible test for quantitative LVEF and visual regional wall motion analysis. Our results imply the procedure may be useful for serial follow-up of patients with coronary artery disease and for the evaluation of the efficacy of medical or interventional treatment.

First-pass radionuclide angiography during bicycle and treadmill exercise.

Treadmill testing is usually preferred over cycle ergometry because of the greater sensitivity in diagnosing coronary artery disease. Treadmill testing has only recently been used with radionuclide angiography (RNA) because patient motion makes RNA imaging difficult. In this study we evaluate the comparability of treadmill and cycle exercise RNA with a dual isotope motion correction technique. Volunteer patients (n = 27) performed first-pass RNA during maximal exercise using both cycle ergometer and treadmill. Exercise capacity was greater during treadmill exercise (8.1 +/- 2.4 vs 7.5 +/- 2.2 METs). Twenty-three of 27 treadmill and all cycle ergometer exercise studies were technically adequate. Maximal heart rate was greater during treadmill exercise (150 +/- 24 vs 143 +/- 25 beats * min-l), however, systolic blood pressure was greater during cycle ergometry (174 +/- 23 vs 188 +/- 25 mmHg), resulting in no difference in heart rate times systolic blood pressure (25.7 +/- 7.2 vs 26.9 +/- 6.0). There were no differences between treadmill and cycle ergometer for peak exercise left ventricular ejection fraction (56% +/- 13% vs 57% +/- 14%) (r = 0.89). Calculated left ventricular end-diastolic volume was not different at rest (183 +/- 42 ml vs 176 +/- 44 ml) but differed significantly at peak exercise (282 +/- 75 ml vs 231 +/- 60 ml). The clinical impression, based on wall motion and left ventricular ejection fraction was very similar between treadmill and cycle ergometer. Treadmill exercise RNA is feasible, with about 85% of studies likely to be technically adequate. The overall clinical results are very similar to cycle exercise RNA, although the ordinarily expected advantages of treadmill exercise were largely absent.

Value of radionuclide rest and exercise left ventricular ejection fraction in assessing survival of patients after thrombolytic therapy for acute myocardial infarction: Results of thrombolysis in myocardial infarction (TIMI) phase II study

This study sought to determine the prognostic value of rest and exercise left ventricular ejection fraction in patients receiving thrombolytic therapy as part of the Thrombolysis in Myocardial Infarction (TIMI) trial. In the prethrombolytic era, ejection fraction at rest as well as during exercise was an important prognostic index in patients recovering from acute myocardial infarction. The prognostic value of these measurements in the thrombolytic era is not clear. As part of the TIMI II protocol, we obtained radionuclide left ventricular ejection fraction at rest and during symptom-limited submaximal supine exercise. Measurements were related to 1-year all-cause as well as cardiac mortality. In addition, the relation between ejection fraction obtained at rest and 1-year cardiac mortality in this study was compared with the relation established previously in the prethrombolytic era by the Multicenter Postinfarction Research Group. A distinct relation was noted between left ventricular ejection fraction at rest and all-cause mortality. The highest mortality rate (9.9%) was noted in patients with an ejection fraction < 30%. Those not undergoing a study had a 1-year mortality rate of 6.2%. Peak exercise ejection fraction provided prognostic information similar to that of rest ejection fraction. Likewise, change in ejection fraction from rest to exercise did not appreciably improve prognostic impact. Rest left ventricular ejection fraction is an important prognostic index in patients receiving thrombolytic therapy. Peak exercise ejection fraction and the change in ejection fraction from rest to exercise do not provide appreciable prognostic data beyond those obtained at rest. Patients unable to exercise or those not having a rest study have a poor prognosis. When compared with the Multicenter Postinfarction Research Group data, there was strong evidence of a difference in survival in the two studies. At any level of ejection fraction, mortality was lower in TIMI II patients than in patients in the prethrombolytic era.

Thallium-201 lung uptake and peak treadmill exercise first-pass ejection fraction

Increased thallium-201 lung uptake immediately after exercise has been shown (1) to be a marker for extensive coronary artery disease, (2) to correlate with low rest and exercise left ventricular ejection fraction by supine gated blood pool scintigraphy, and (3) to be a powerful independent predictor of future cardiac events. Exercise left ventricular ejection fraction measured during upright exercise by the first-pass technique has also been shown to be a powerful independent prognostic variable. Combined perfusion and exercise left ventricular ejection fraction can be acquired by using the technetium 99m-based myocardial perfusion agents and offers an alternative protocol to stress/redistribution thallium imaging. It is therefore clinically important to understand the relation between exercise lung heart thallium uptake and exercise left ventricular ejection fraction. Accordingly, both these measurements were acquired in 38 patients with documented coronary artery disease who underwent two treadmill exercise studies. Parameters obtained from the first-pass study that are known to affect lung thallium uptake were correlated with exercise lung/heart thallium ratios; lung/heart ratios were used in a model to predict exercise left ventricular ejection fraction values. Exercise left ventricular ejection fraction and peak filling rate showed significant negative correlations with thallium lung/heart ratio, but the first-pass variables examined were not independently predictive of thallium lung uptake. The chance of finding an abnormal thallium lung/heart ratio at exercise LVEF of 40% is only 52%, whereas the chance of finding an abnormal ratio at exercise LVEF of 30% is 74%. These data suggest that, although there is an overall significant inverse correlation between exercise left ventricular ejection fraction and lung/heart thallium ratio, moderately reduced exercise left ventricular ejection fraction values cannot be reliably predicted from lung/heart thallium ratios.

758–3 Right Ventricular Ejection Fraction is an Independent Predictor of Maximum Oxygen Consumption in Advanced Heart Failure

Maximum oxygen consumption (MVO 2 ), left ventricular ejection fraction (LVEF), and left ventricular end-diastolic volume index (LVEDVI) are important determinants of prognosis in heart failure (HF). To determine the ventriculographic parameters influencing MVO 2 , simultaneous cardiopulmonary exercise testing (cycle ergometry) and first-pass rest and exercise radionuclide ventriculography were performed in 66 patients with advanced HF (age 51 ± 9.9 mean ± SD, NYHA 3 ± 0.6, LVEF 0.22 ± 0.07, RVEF 0.29 ± 0.11, LVEDVI 154 ± 49 m1/M 2 ) during initial cardiac transplant evaluation. Mean percent predicted age-sex adjusted MVO 2 achieved (%MVO 2 ) was 38 ± 12%. Univariate predictors of %MVO 2 included RVEF at rest (p = 0.001). RVEF at peak exercise (p = 0.001), %maximum heart rate achieved (%MHR, p &lt; 0.01), LVESVI (p &lt; 0.05). and NYHA (p = 0.05). Resting HR, resting or peak systolic or diastolic blood pressure, resting or peak exercise LVEF, exercise-related rise or fall &gt; 0.05 in either LVEF or RVEF, rest or peak exercise cardiac index, rest or peak exercise LVEDVI, NYHA, and diagnosis were not significant univariate predictors of %MVO 2 . RVEF at rest (p = 0.001) and %MHR (p = (0.01) were the only independent predictors in a multiple linear regression model. In patients with advanced HF, 1) RVEF is an independent predictor of %MVO 2 and 2) neither rest or exercise LVEF predicts %MVO 2 .

Rest and treadmill exercise first-pass radionuclide ventriculography: validation of left ventricular ejection fraction measurements.

To assess the accuracy of rest and treadmill exercise first-pass radionuclide ventriculographic measurements of left ventricular ejection fraction (LVEF), 40 patients underwent treadmill exercise first-pass and bicycle exercise equilibrium radionuclide ventriculography. To determine the frequency of technically adequate treadmill exercise first-pass studies, an additional 128 consecutive patients undergoing treadmill exercise first-pass procedures during stress 99mTc-labeled sestamibi myocardial perfusion studies were assessed. The treadmill exercise first-pass procedure used a multicrystal camera and an 241Am point source to allow for correction of patient motion. Excellent correlations were observed between resting first-pass and resting equilibrium LVEF (r = 0.91; standard error of the estimate = 5.6). A high correlation was also observed between treadmill exercise first-pass and bicycle equilibrium exercise LVEF measurements (r = 0.85, standard error of the estimate = 7.6). Treadmill first-pass LVEF systematically underestimated the bicycle equilibrium LVEF. Intraobserver agreement for rest and exercise first-pass LVEF was high (r values of 0.98 and 0.94, respectively). Of the 168 consecutive treadmill exercise first-pass studies evaluated for technical adequacy, 21 (12.5%) were deemed technically inadequate, with most of the sources of error being avoidable. The frequency of technically adequate studies was as high (87%) in high levels of exercise (Bruce stages 3 and 4) as in lower levels (88%). The findings of this study validate the first-pass treadmill exercise LVEF measurement. This procedure now provides the option for combining the information of peak treadmill exercise LVEF with measurements of exercise myocardial perfusion from the same injection of radioactivity.

Exercise testing and training in physically disabled men with clinical evidence of coronary artery disease

A prospective, randomized, controlled clinical trial in patients with coronary artery disease (CAD) and a concurrent physical disability evaluated the effects of a home exercise training program on cardiovascular function and blood lipids. Eighty-eight men between the ages of 42 and 72 years (mean 62) with documented CAD and a physical disability with functional use of ≥2 etremities including 1 arm were randomized to either a 6-month home exercise training program using wheelchair ergometry or to a control group that received usual and customary care. Both groups received dietary instructions and were requested to follow a fat-controlled diet. Exercise test variables with echocardiography and blood lipids were measured at baseline and at 6 months. The home exercise training group significantly improved both peak exercise left ventricular ejection fraction (p = 0.007) and fractional shortening (p = 0.01) between baseline to 6 months, whereas the control group showed no significant changes. Exercise training effects of decreased resting heart rate (p = 0.03) and decreased peak rate pressure product (p = 0.03) were also found in the treatment group. No exercise-related cardiac complications occurred. Both groups significantly (p ≤ 0.01) increased high-density lipoprotein cholesterol levels. These results indicate that physically disabled men with CAD can safely participate in a home exercise training program which may result in intrinsic cardiac benefits. The metabolic cost of activities of daily living imposed on this disabled popu lation may also have a positive effect on high-density lipoprotein cholesterol levels.

Novel approach to the interpretation of long-term "deterioration" in ejection fraction in individual patients with coronary artery disease.

The long-term predictability of left ventricular ejection fraction (LVEF) measurements was evaluated with particular emphasis on the assessment of deterioration in individual patients whose coronary artery disease was initially treated medically. Prospective pilot study. Regional cardiac centre. 60 minimally symptomatic patients with coronary artery disease who, after arteriography, were initially treated medically. Measurement of LVEF by first pass exercise radionuclide ventriculography at baseline and six months later without interruption of usual anti-ischaemic medication. Baseline and six-month studies were analysed independently of each other. Based on 51 patients who remained event free, 95% prediction intervals were derived for prognostic LVEF indices to suggest the minimum change from baseline that might be considered clinically important in the individual patient, alerting clinicians to the need for closer review. At six-month ventriculography, 22 patients showed apparent deterioration in exercise LVEF or the change in LVEF with exercise (delta LVEF). Only two patients had six-month values below the lower limit of 95% prediction intervals, compared with 15 when 95% group confidence intervals (z = 3.33, p < 0.001) were used. When delta LVEF = 0 at baseline, the lower limit of 95% prediction intervals allowed for an exercise induced fall at six months of < or = 13%. For a baseline exercise LVEF of 50% (just normal), the lower limit of 95% prediction intervals was 38%--that is, the exercise LVEF could be measured as low as 38% > or = six months later without necessarily indicating or missing true deterioration. In the follow up of minimally symptomatic patients with coronary artery disease, serial long-term changes, in particular "deterioration," in prognostic LVEF indices may be interpreted more meaningfully with reference to 95% prediction intervals.

Left ventricular function response to exercise in normotensive obese subjects: influence of degree and duration of obesity

This study has been designed to evaluate whether duration and severity of obesity can influence left ventricular function response to exercise in obese subjects without other known cardiovascular risk factors such as hypertension, diabetes or hyperlipoproteinemia. A total of 29 obese subjects were included and they were divided, according to their body mass index and to Garrow's criteria as follows: Overweight or mildly obese subjects: body mass index from 25 to 30 kg/m 2; moderately obese subjects: body mass index > 30 and < 40 kg/m 2. Both obese groups were further subdivided according to their duration of obesity evaluated by accurate anamnesis in subgroup A (duration of obesity less than 120 months) and subgroup B (duration of obesity more than 120 months). Left ventricular ejection fraction was detected by blood pool gated radionuclide angiocardiography both at rest and after symptom-limited bicycle ergometer procedure. At peak exercise left ventricular ejection fraction increased significantly ( p < 0.05) only in overweight subjects. Exercise produced an increase of left ventricular ejection fraction in 14 overweight and in 5 moderately obese subjects and a decrease in 2 moderately obese subjects. At peak exercise mean heart rate and mean blood pressure increased significantly ( p < 0.001) in both groups. When obese subjects were subgrouped according to duration of obesity, left ventricular ejection fraction increased significantly ( p < 0.05) only in overweight subjects with duration of obesity less than 120 months. Duration of obesity correlated inversely with percent change in left ventricular ejection fraction (EF) at peak exercise (ΔEF) ( r = −0.59; p < 0.001). No correlation between body mass index and ΔEF and between EF at rest and ΔEF was observed. Our results suggest that higher degree and higher duration of obesity can impair left ventricular function response to exercise. In view of this, a noninvasive evaluation of left ventricular function could be useful to detect cardiac dysfunction early in subjects with higher degree and higher duration of obesity.

Improvement in left ventricular function after rapid weight loss in obesity.

The effect of rapid weight reduction on left ventricular function and blood pressure was studied in 34 obese subjects, who all weighed more than 30% above their ideal body weight. Subjects with co-existing hypertension (N = 15) and proven coronary artery disease (N = 9) were included to assess contributions from these factors. Blood pressure (BP) was measured both indirectly and by direct ambulatory intra-arterial methods. Radionuclide ventriculography was performed at rest and at exercise, before and after dieting, which was supervised in hospital (daily intake 330 kCal day-1 for 4 weeks). Dieting induced a weight loss of (mean +/- SD) 9.6 +/- 3.5 kg (P less than 0.0001) in the whole group. The mean daytime intra-arterial blood pressure fell from 157 +/- 23/90 +/- 15 to 144 +/- 21/85 +/- 13 mmHg (P less than 0.0001). The fall in ambulatory intra-arterial diastolic blood pressure did not reach significance in the normotensive and ischaemic groups. The mean resting left ventricular ejection fraction (LVEF) in the whole group showed a significant reduction after weight loss from 61 +/- 10% to 56 +/- 6% (P less than 0.005). Although the individual groups showed a fall in LVEF, the effect was most marked in the hypertensive group, from 65 +/- 9% to 57 +/- 5% (P less than 0.002). Before dieting none of the groups achieved a 'normal' 5% rise in LVEF above basal in response to exercise, the hypertensive and the ischaemic groups both showing non-significant falls. This phenomenon was, however, reversed after weight loss.(ABSTRACT TRUNCATED AT 250 WORDS)

Predicting cardiac mortality after uncomplicated myocardial infarction by exercise radionuclide ventriculography and exercise-induced ST segment elevation.

In 183 consecutive patients with recent, uncomplicated myocardial infarction, the following variables were associated with 4-year cardiac death: haemodynamic decompensation with exercise (P = 0.01), left ventricular ejection fraction at rest (P = 0.004) and at peak exercise (P = 0.003), persistent ST segment elevation at rest in the area of infarction = (P = 0.004), exercise-induced ST segment elevation (P = 0.02), and late aneurysmal evolution (P = 0.01). Exercise left ventricular ejection fraction was the sole variable selected by Cox regression analysis as an independent predictor of cardiac death. In 40 patients with ST segment elevation at rest, left ventricular ejection fraction was 42 +/- 17% at rest and 40 +/- 18% at peak exercise, versus 52 +/- 12% and 52 +/- 14% in the remaining patients (both P less than 0.01). Among these 40, 16 (all with anterior infarction) also had exercise-induced ST segment elevation; their ejection fraction was 32 +/- 13% at rest, 30 +/- 13% during exercise, versus 53 +/- 15% and 53 +/- 15% in 129 patients with no ST segment elevation either at rest, or during exercise (both P less than 0.01). The 4-year risk of death was 20% in the former 40 patients, 36% in the latter 16, while in the complete absence of ST segment elevation, such risk was 3%. All 14 patients with ST segment elevation only during exercise were alive after 4 years: their left ventricular ejection fraction was 47 +/- 12% at rest, 45 +/- 13% with exercise. ST segment elevation was associated with late aneurysmal evolution but not with exercise-induced ischaemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of Regular Anti-Anginal Monotherapy on Rest and Exercise left Ventricular Ejection Fraction in Stable Coronary Artery Disease

Effect of Regular Anti-Anginal Monotherapy on Rest and Exercise left Ventricular Ejection Fraction in Stable Coronary Artery Disease

Right and left ventricular performance after single and double lung transplantation

Twelve single lung and nine double lung transplant recipients were studied before transplantation and at 3 months and 1 year after transplantation with serial right and left ventricular radionuclide angiograms. The resting right ventricular ejection fraction increased in the double lung recipients from 31% ±5% before transplantation to 43% ± 11% at 3 months after transplantation (p < 0.05) and then remained stable to 1 year. The single lung recipients also demonstrated a significant rise in ejection fraction from 25% ± 11% before transplantation to 36% ± 12% at 3 months after transplantation. Again, this remained stable to 1 year. The exercise right ventricular ejection fraction also showed a significant posttransplantation rise in the double lung recipients (p < 0.005) that remained stable to 1 year. In the single lung recipients a trend was seen for a rise in the exercise right ventricular ejection fraction that did not reach statistical significance by 1 year after transplantation. Neither group had a significant change in rest or exercise left ventricular ejection fraction. The systemic blood pressure increased significantly by 1 year after transplantation in both groups. The heart rate increase with exercise at 3 months after transplantation was significantly greater in the single lung group (42 ± 13 beats/min) than in the double lung group (14 ± 13 beats/min) (p < 0.005). These data indicate that a significant improvement in right ventricular function occurs after single and double lung transplantation.

Early prognosis after thrombolysis: value of exercise radionuclide ventriculography performed on anti-ischaemic medication

We examined the prognostic value of exercise radionuclide ventriculography (RNV) performed on anti-ischaemic medication following thrombolysis. Within 3 months of thrombolysis for first myocardial infarction, 31 medically treated patients with revascularisable but non-critical and minimally symptomatic coronary disease had left ventricular ejection fraction (LVEF) measured by first-pass exercise RNV. This was first performed off treatment and then repeated within 4 weeks on patients' regular medication. Follow-up at 12 months post-thrombolysis showed that 5 patients (Group I) had suffered significant recurrent symptoms (worsening angina requiring revascularisation in 3, unstable angina in 1, reinfarction in 1), but 26 remained well (Group II). Both groups were similar in age, post-thrombolytic severity of coronary disease, exercise LVEF whether off (39% vs 43%) or on medication (43% vs 44%), and change in LVEF with exercise ([symbol: see text]LVEF) off medication (-11% vs - 3%). However, on medication, there was a significant difference in mean [symbol: see text]LVEF between Groups I and II (-11% vs + 5%, P = 0.0008, 99% confidence interval = 4 to 26%). Thus, following thrombolysis, an abnormal [symbol: see text]LVEF despite anti-ischaemic medication may identify patients at risk of significant early recurrent ischaemia. Post-thrombolysis prognostic testing by exercise RNV may therefore be of greater value when performed on rather than off medication.

Left and right ventricular systolic function and exercise capacity with coronary artery disease

This prospective study of symptom-limited supine ergometry was conducted to determine the contributions of right ventricular (RV) and left ventricular (LV) systolic function to the exercise capacity of a cohort of patients with coronary artery disease (CAD). Patients with unstable angina, angiographically proven CAD (n = 53) and stable symptoms after medical therapy or angioplasty were included. Documented myocardial infarction (≥2 weeks before exercise) was present in 43 of 53 patients. Angina was the limiting symptom in 11 of 53; the other 42 stopped exercise with dyspnea or fatigue, or both. Oxygen consumption was measured on-line during exercise with a metabolic cart. RV ejection fraction and LV ejection fraction were measured by validated methods from gated blood pool radionuclide ventriculography. There were weak but statistically significant correlations between exercise oxygen consumption and exercise RV ejection fraction (r = 0.30, p < 0.05) and between exercise oxygen consumption and exercise LV ejection fraction (r = 0.38, p < 0.01). Multivariate regression analysis, including exercise RV ejection fraction, exercise LV ejection fraction and exercise heart rate versus exercise oxygen consumption revealed a better relation (r = 0.48, p < 0.005) than any variable in univariate regression. The values of RV and LV ejection fraction at rest did not correlate significantly (r = 0.2, difference not significant), but the exercise values did correlate weakly (r = 0.41, p < 0.01). The reserve of LV ejection fraction, defined as exercise minus rest value, correlated weakly with exercise oxygen consumption (r = 0.32, p < 0.05). Taken together, these data suggest: (1) exercise capacity in stabilized patients with CAD is multifactorial, (2) the systolic function of both ventricles contribute to the exercise capacity of patients with CAD, and (3) the function of the 2 cardiac ventricles appears to become more closely linked at symptom-limited exercise.

Maximal oxygen uptake in severe aortic regurgitation: A different view of left ventricular function

Respiratory gas exchange was used to assess left ventricular (LV) function in 22 patients with severe aortic regurgitation (19 men and three women, aged 18 and 70 years, mean 49 years). Anaerobic threshold and symptom-limited maximal oxygen consumption (VO 2 max) were measured during treadmill exercise, and the results were compared with conventional echocardiographic and radionuclide indices of LV systolic function. The results were considered with respect to the patients' New York Heart Assoclation functional class. Both rest and exercise LV ejection fractions were variable, but the mean results were similar in all classes. The echocardiographic indices of LV cavity dimensions, fractional shortening, radius/thickness ratio, and systolic wall stress also showed a wide range but with similar mean results in each class. In contrast, VO 2 max and anaerobic threshold showed a relationship to functional class. VO 2 max was 32.4 ± 3.4 ml/kg/min in age-matched control subjects; in the patients it was 27.9 ± 4.7 in class I, 24.7 ± 5.7 in class II, and 14.2 ± 2 in the combined class III/IV. Results in patients in classes I and II were similar, but both groups were significantly different from control subjects ( p < 0.05) and from patients in class III/IV ( p < 0.01). About half of the patients with moderate LV dysfunction (judged by reduced VO 2 max) were asymptomatic, and LV function was imparired in 4 of 10 patients in class I. Thus, unlike conventional indices of LV function, VO 2 max appeared capable of distinguishing patients with moderate-to-severe LV dysfunction from those with little or no LV dysfunction. Measurement of respiratory gas exchange appears to be a valid and useful supplementary means of assessing LV function in severe aortic regurgitation. Further long-term evaluation is required.