Echocardiographic assessment of myocardial performance after prolonged strenuous exercise

To determine the effect of strenuous prolonged exercise on systolicand diastolic left ventricular function, 11 non-elite marathonrunners aged 37±7 years (mean±SD) were studiedbefore and during early recovery from a marathon race. Cavitydimensions, wall thickness, and fractional shortening were computedfrom two-dimensionally guided M-mode echocardiograms. Dopplerleft ventricular inflow tract recordings were analysed for peakearly and late velocities and their ratio. In seven subjects,heart frequency was recorded throughout the race. These subjectsran the marathon at 87±4% of their maximal heart rate.Left ventricular diastolic dimension was slightly reduced atthe end of the race (49·4±4·2 mm to 47·3±5·1mm:P<0·05). Fractional shortening remained unchanged,although blood pressure (P<0·001) and systolic itall stress (P<0·01) were decreased. The left ventricularfilling pattern was unchanged, and the ratio of early to latevelocities remained constant. These results suggest that thefractional shortening was a result of the opposing effects ofchanges in preload and afterload. However, the absence of achange in the end systolic dimension, despite a marked reductionin afterload and the occurrence of septal akinesia in one subjectafter the race could only suggest that strenuous prolonged exercisemay alter mnyocardial performance.     

Echocardiographic detection of acute myocardial ischemia during percutaneous transluminal coronary angioplasty

The usefulness of echocardiography and Doppler for the detection of acute myocardial ischemia was evaluated during right coronary artery occlusion in 20 patients. The echocardiographic findings were compared with the occurrence of chest pain, and to electrocardiographic and hemodynamic changes obtained during percutaneous transluminal coronary angioplasty. Our results confirm that, even in the case of small segmental myocardial ischemia, two-dimensional echocardiography is superior to all other measured parameters. In contrast, Doppler examination of transmitral flow is not sensitive enough for the detection of such small segmental myocardial ischemia induced by right coronary artery occlusion.     

Influence of exercise training soon after myocardial infarction on regional myocardial perfusion and resting left ventricular function.

There is scant information regarding the effect of exercise training begun soon after hospital discharge for myocardial infarction (MI) with respect to subsequent improvement in exercise tolerance, enhancement of regional myocardial perfusion, or left ventricular function. Accordingly, 19 post-MI patients (mean age 53 +/- 7 years) underwent treadmill exercise quantitative thallium-201 (Tl-201) scintigraphy and rest radionuclide angiography (RNA) prior to and after 12 weeks of thrice-weekly exercise training which was targeted to 70-85% of maximum exercise heart rate achieved. Training was begun at 25 +/- 3 days after hospital discharge. Eight Tl-201 scan segments were each scored from 1-6 points based upon uptake and washout criteria with 6 being the most severe defect (greater than 50% reduction in Tl-201 events with no delayed redistribution). When matched to the pretraining peak workload on exercise testing, 12 weeks of training significantly lessened heart rate (120 +/- 4 to 97 +/- 4, p less than 0.001), peak systolic blood pressure (142 +/- 6 to 129 +/- 5 mmHg, p less than 0.01), and significantly reduced double product [17.2 +/- 10.8 to 12.7 +/- 9 (x10(3), p less than 0.001]. Training was associated with a reduction of exercise-induced ST depression or angina (42 to 16%) which was not statistically significant. The mean resting by RNA ejection fraction was 50 +/- 3% prior to training and 51 +/- 3% after training. There was no significant change in overall Tl-201 defect score or the number of defect regions per patient scan comparing pre- and post-training scintigrams.(ABSTRACT TRUNCATED AT 250 WORDS)     

Echocardiographic Determination of Epicardial Adipose Tissue in Healthy Bonnet Macaques

Background: Nonhuman primates have served as models for human cardiovascular (CV) and metabolic diseases. Recently, echocardiographic measurement of epicardial adipose tissue (EAT) thickness has been shown to be a reliable marker of visceral adiposity, and greater EAT is associated with increased CV risk, left ventricular (LV) hypertrophy, and metabolic syndrome. The objective of the present study was to determine EAT thickness in apparently healthy bonnet macaques and assess its relations with anthropometric and CV variables. Methods: Echocardiography was performed on 61 monkeys (41 females and 20 males, mean age 13.0 ± 4.7 years). EAT was measured on the right ventricular free wall in parasternal windows. Applanation tonometry was performed in 25 unselected monkeys using a SphygmoCor pulse wave system. Results: The mean EAT thickness was 2.4 ± 0.6 mm. EAT thickness was directly correlated with age (r = 0.26, P = 0.04), male gender (r = 0.47, P < 0.01), weight (r = 0.42, P < 0.01), crown–rump length (r = 0.45, P < 0.01), BMI (r = 0.38, P < 0.01), diastolic BP (r = 0.46, P = 0.01), and HR (r =−0.49, P < 0.01). EAT thickness also correlated with augmentation index (r = 0.42, P = 0.04), LV mass (r = 0.48, P < 0.01), and left atrial (LA) diameter (r = 0.26, P = 0.04). Intra‐ and interobserver coefficients of variation between measurements of EAT were 1.4% and 3.7%. On multivariate analysis adjusting for age, gender, weight, and CRL, EAT was independently related to age and weight (r²= 0.47, P < 0.01). Conclusion: This study found echocardiography to be a feasible and practical method to evaluate EAT in nonhuman primates. In bonnet macaques, EAT thickness correlates with LV and LA dimensions and augmentation index, and is independently related to age and weight. (ECHOCARDIOGRAPHY 2010;27:180‐185)     

Myocardial dysfunction and abnormal left ventricular exercise response in autonomic diabetic patients

In diabetic patients, the pathophysiologic mechanisms of exercise-induced left ventricular (LV) dysfunction remain controversial. In this study, the role of myocardial contractility recruitment in determining an abnormal LV response to isometric or dynamic exercise has been investigated in 14 diabetic patients with autonomic dysfunction. Ischemic heat disease was excluded by the absence of LV wall motion abnormalities induced by isotonic and isometric exercise and by coronary angiography. Left ventricular and myocardial function were studied at rest, and during isometric and isotonic exercise, by two-dimensional echocardiography; moreover, recruitment of an inotropic reserve was assessed by postextra-systolic potentiation at rest and at peak handgrip. An abnormal response of LV ejection fraction to isometric (9/14) or to dynamic (8/14) exercise was frequent in study patients. In these patients, baseline myocardial contractility was normal, and the significant increase in ejection fraction by postextrasystolic potentiation indicated a normal contractile reserve (65 ± 7% vs. 74 ± 6%, p=0.001). Nevertheless, the downward displacement of LV ejection fraction-systolic wall stress relationships during exercise suggests an inadequate increase in myocardial contractility. However, the abnormal ejection fraction at peak handgrip was completely reversed by postextrasystolic potentiation (67 ± 6% vs. 58.1 ± 10%, p=0.008), a potent inotropic stimulation independent of the integrity of adrenergic cardiac receptors. A defective inotropic recruitment, despite the presence of a normal LV contractile reserve, plays an important role in deexercise LV dysfunction in diabetic patients with autonomic neuropathy.     

The myocardial performance index in patients with aortic stenosis

OBJECTIVES: This study was designed to determine the effect of chronic afterload on a Doppler-derived myocardial performance index (MPI) combining both systolic and diastolic left ventricular dysfunction. METHODS: The study included 36 patients with a diagnosis of aortic stenosis and 36 normal subjects. Doppler-derived myocardial performance index (MPI), defined as the sum of the isovolumic contraction time and isovolumic relaxation time divided by ejection time, was measured from the mitral valve inflow and left ventricular outflow velocity patterns and was then related to the aortic valve area, valve gradient, and other echocardiographic variables. RESULTS: The values of the Doppler-derived MPI in the patients with aortic stenosis were significantly higher than those in the controls (0.54 +/- 0.20 vs 0.38 +/- 0.04, respectively; P < 0.001). Transmitral deceleration time and the E/A ratio ( r = 0.47 and r = 0.35, respectively; P < 0.05) were significant univariate correlates, and mitral deceleration time was the only significant correlate of MPI. However the index did not correlate with aortic valve area, peak and mean valve gradients, left ventricular mass, or age. CONCLUSIONS: Doppler-derived MPI reflects severity of global left ventricular dysfunction in patients with aortic stenosis and may be of clinical value in this patient population.     

Cardiac function and maximal exercise capacity early after acute myocardial infarction.

The purpose of the study was to assess the relationship between left and right ventricular function measured at rest and maximal exercise capacity in patients with recent acute myocardial infarction (AMI). Forty-three male patients (Killip Class I, n = 36; Killip Class II, n = 7) with a wide range of left ventricular (LV) function and size underwent graded bicycle exercise testing less than 4 weeks after AMI (mean 21 days, 17-27). None of the patients had exercise limiting factors other than dyspnoea and fatigue. Left and right ventricular ejection fractions were determined by a radionuclide ventriculographic method which also allowed determination of absolute LV volumes and actual LV peak filling rate. LV ejection fraction had a weak association to estimated maximal oxygen uptake (VO2 max) (r = 0.37). No association was found between LV size, LV stroke volume, or LV peak filling rate and estimated VO2 max. Similarly, right ventricular ejection fraction showed no correlation to estimated VO2 max. Patients with well preserved LV function had a higher exercise induced increase in systolic blood pressure than patients with reduced LV function, but the increase in systolic blood pressure could not be used to estimate LV function with any reasonable accuracy. We conclude that the maximal exercise capacity of patients with recent AMI is virtually independent of their left and right ventricular function determined at rest, and that exercise testing and radionuclide ventriculography should be regarded as complementary procedures in the evaluation of patients with AMI.     

Quantitative Doppler tissue imaging as a correlate of left ventricular contractility

Doppler tissue imaging is a new noninvasive imaging modality that allows quantitation of the low intensity, high amplitude Doppler shifts in the range of myocardial tissue motion. This study was performed to test the hypothesis that Doppler tissue imaging may provide unique information reflecting left ventricular systolic function, and to test the relationship between myocardial tissue velocity and noninvasive measures of ventricular contractility. Nine patients with mild or moderate mitral insufficiency and no regional wall motion abnormality were studied during dobutamine stress echocardiography. Left ventricular ejection fraction and peak systolic velocity of the sub- endocardial left ventricular posterior wall were quantified at baseline and at peak stress and compared with estimated peak dP/dt. During dobutamine infusion, ejection fraction increased from 41.7±22.2 (range 14 to 70) % to 56.6±27.9 (range 17 to 84) % (p=0.001), peak systolic velocity increased from 22.7±4.2 (range 18 to 28) mm/sec to 35.3±10.1 (range 20 to 47) mm/sec (p=0.004), and dP/dt increased from 1050±322 (range 613 to 1574) mm Hg/sec to 1766±768 (range 936 to 3000) mm Hg/sec (p=0.01). Although there were good correlations between left ventricular dP/dt and both ejection fraction (R=0.75) and peak systolic velocity (R=0.81), the correlation between change in dP/dt and change in myocardial velocity (R=0.75) was better than that between change in dP/dt and change in ejection fraction (R=0.36). These data support the hypothesis that myocardial velocity determined with Doppler tissue imaging reflects myocardial contractility, and that catecholamine- induced alteration in contractility is better reflected by changes in myocardial velocity than by changes in ejection fraction.     

Monitoring of cardiac output during exercise in coronary patients: a Doppler study

The monitoring of aortic blood flow velocities by transcutaneous continuous-wave Doppler was performed in 45 patients to determine, non-invasively, the haemodynamic response to exercise in subsets of coronary patients during a multistage supine exercise tests. Group I consisted of 14 patients with ischaemia on effort (IE); group II, 12 patients with both IE and prior myocardial infarction (MI); group III, 19 patients with MI and no IE; there were also 12 normals. Peak flow velocity (PV) indices of cardiac output (CO), of peripheral resistance (PR) and of stroke work (SW) were measured every min. Resting CO was lower and PR higher in coronary patients than in normals. With exercise, for the same muscular work, CO increased less in IE patients (group I: y = 26.9 + 1.8 x cm sec-1; Group II: y = 21.9 + 1.8 x cm sec-1) than in MI (group III: y = 26.6 + 2.1 x cm s-1) and in normals (y = 35 + 2.7 x cm s-1) and PR decreased less. This suggested a more efficient distribution of CO towards working muscles. A shallower increase in SW was observed in all coronary patients in comparison with normals even if resting SW was significantly lower only in patients with MI (groups II and III). PV increased up to peak exercise only in group III, while it tended to plateau in ischaemic patients even earlier than IE occurred on the ECG.(ABSTRACT TRUNCATED AT 250 WORDS)     

102名健康中年人运动试验前后舒张功能的正常变异

目的：观察健康中年人运动试验前后舒张功能的变化。方法：使用多普勒彩色超声心动图仪分别测量102名健康中年人静息时、运动试验后15min及60min的E峰最大流速（EPFV）、A峰最大流速（APFV）、EPFV／APFV（EK／A）比值、E峰减速时间（Edt)。结果：健康中年人运动试验后15min及60min EPFV、E／A比值、Edt与静息时相比均明显下降。APFV运动试验前后无差异。运动试验后15min E/A比值比静息时降低0．5以内。结论：健康中年人运动试验后舒张功能存在生理性下降，运动后15min的E／A比值较静息时明显降低，但应＜0．5。     

Radionuclide assessment of cardiac performance and myocardial perfusion in congestive cardiomyopathies.

To determine the reliability of radionuclide techniques in the diagnosis of congestive cardiomyopathy (COCM), the function of the right ventricle (RV) and left ventricle (LV) was evaluated in 32 patients with COCM and 21 normal subjects using radionuclide angiography (first pass and gated blood pool scan) combined with quantitative 201 thallium (Tl) myocardial perfusion imaging. In COCM parameters of RV and LV performance were significantly reduced (p less than 0.01); regional wall motion analysis revealed a reduced radial shortening ability (p less than 0.05). 201 Tl distribution within the myocardium was not different between COCM and N; however, segmental 201Tl-uptake was significantly reduced (p less than 0.01). RV free wall was visualized on 201Tl scan in 80% of patients with COCM. There was no correlation between RV free wall visualization and RV hemodynamics. Thus these scintigraphic aspects provide an atraumatic and sensitive technique for the evaluation of patients with COCM.     

Echocardiographic assessment of hypertensive patients with or without hyperhomocysteinemia

The study was designed to assess left ventricular (LV) systolic and diastolic function in hypertensive patients with or without Hhcy. The study participants consisted of 40 hypertensive patients with Hhcy, 40 hypertensive patients without Hhcy and 40 age-matched healthy control participants. Cardiac functions were determined using echocardiography and the Tei index was calculated for analysis. LAVI (left atrial volume index), IVST (interventricular septum thickness in diastole), PVST (posterior ventricular septum thickness in diastole), LVMI (left ventricular mass index), E/A (peak early and late diastolic transmitral filling flow velocities ratio), DT (deceleration time of the E wave), IRT (isovolumic relaxation time), and the Tei index were different in the hypertensive patient groups (hypertension with Hhcy and hypertension without Hhcy) compared with the controls. The Tei index was significantly higher in the hypertensive groups compared with the controls (0.62?±?0.05, 0.51?±?0.04, and 0.40?±?0.04, respectively, p?2), E/A (0.73?±?0.22 versus 0.92?±?0.14), DT (93.1?±?6.9 versus 84.3?±?8.1?ms), IRT (93.1?±?6.9 versus 84.3?±?8.1?ms) and the Tei index. Significant correlations were observed between serum homocysteine levels and LV diastolic function parameters (LAVI: r?=?0.39, E/A: r?=??0.32, DT: r?=?0.47, IRT: r?=?0.51, p?相似文献   

Cardiac function and maximal exercise capacity early after acute myocardial infarction

The purpose of the study was to assess the relationship betweenleft and right ventricular function measured at rest and maximalexercise capacity in patients with recent acute myocardial infarction(AMI). Forty-three male patients (Killip Class I, n=36; KillipClass II, n=7) with a wide range of left ventricular (LV) functionand size underwent graded bicycle exercise testing less than4 weeks after AMI (mean 21 days, 17–27). None of the patientshad exercise limiting factors other than dyspnoea and fatigue.Left and right ventricular ejection fractions were determinedby a radionuclide ventriculo graphic method which also alloweddetermination of absolute LV volumes and actual LV peak fillingrate. LV ejection fraction had a tt weak association to estimatedmaximal oxygen uptake (VO₂ max) (r=0·37). No associationwas found between LV size, LV stroke volume, or LV peak fillingrate and estimated VO₂ max. Similarly, right ventricular ejectionfraction showed no correlation to estimated VO₂ max. Patientswith well preserved LV function had a higher exercise inducedincrease in systolic blood pressure than patients with reducedLV function, but the increase in systolic blood pressure couldnot be used to estimate LV function with any reasonable accuracy. We conclude that the maximal exercise capacity of patients withrecent AMI is virtually independent of their left and rightventricular function determined at rest, and that exercise testingand radionuclide ventriculography should be regarded as complementaryprocedures in the evaluation of patients with AMI.     

Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy

OBJECTIVE—To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC).
DESIGN—Prospective observational study.
SETTING—University Hospital.
SUBJECTS—15 patients with ARVC and a control group of 25 healthy subjects.
METHODS—Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, right ventricular inflow tract, and right ventricular body. Wall motion was analysed subjectively. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral, septal, posterior, and anterior positions. Doppler assessment of tricuspid flow and systemic venous flow was also performed.
RESULTS—Assessed by M mode, the total amplitude of the tricuspid annular motion was significantly decreased in the lateral, septal, and posterior positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (E_A) velocity and an accompanying decrease in early (E_A) to late diastolic (A_A) velocity ratio in all positions; the systolic annular velocity was significantly decreased only in the lateral position. Four patients had normal right ventricular dimensions and three were judged to have normal right ventricular wall motion. The patient group had also a significantly decreased tricuspid flow E:A ratio.
CONCLUSIONS—Tricuspid annular measurements are valuable, easy to obtain, and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non-specific sign of the disease. Normal right ventricular dimensions do not exclude ARVC, and subjective detection of early changes in wall motion may be difficult.


Keywords: annular motion; diastolic dysfunction; right ventricular function; tissue Doppler     

Echocardiographic evaluation of left ventricular response to isometric exercise in young insulin-dependent diabetics

Summary In order to evaluate the left ventricular (LV) response to isometric exercise in diabetics, 15 young insulin-dependent diabetic subjects and 12 control subjects of similar age and sex distribution performed a handgrip test during echocardiography. No base-line differences in hemodynamic or echocardiographic parameters were found between diabetic and control subjects. The heart rate and blood pressure responses to handgrip exercise were similar in the two groups, and LV dimensions, shortening fraction and velocity of circumferential fiber shortening remained unchanged in both groups. Three diabetic subjects had an impaired LV functional response to handgrip (a decrease of more than 5 percentage units in the shortening fraction). These 3 patients had high HbA₁ values (17.6·18.2%) and modest correlations existed between decrease in the shortening fraction during handgrip and concentrations of HbA₁ (r=0.70, p<0.01) and fasting blood glucose (r=0.62, p<0.01). Thus, most young insulin-dependent diabetic subjects appear to have a normal LV response to isometric exercise, but poor blood glucose control seems to be accompanied by a slight impairment of LV functional reserve.     

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.     

Doppler echocardiographic assessment of left ventricular filling dynamics in patients with coronary heart disease and normal systolic function

The purpose of this study was to assess altered left ventriculardiastolic filling by noninvasive means in patients with coronaryartery disease and normal systolic pump function. Mitral inflowvelocity was measured by pulsed Doppler, and left ventricularvolumes were obtained from cross-sectional echocardiographyat rest and during upright bicycle exercise. Peak and integratedearly and late diastolic filling velocities were calculatedfrom Doppler-derived time-velocity curves. Studies were performedin normal subjects (group I, n = 8) and in patients with angiographicallyproven coronary artery disease (Group II, n = 18). The ejectionfraction was not significantly different in group II as comparedto group I (group 1, 60 ± 7%; group II, 55 ± 11%).During exercise, ejection fraction increased significantly ingroup I by 7·6%, but did not increase in group II. Inall cases, diastolic filling showed a biphasic pattern. At rest,the major part of diastolic filling occurred during early diastole:the ratio of early filling velocity integral (E) to the latefilling velocity integral (L) was significantly greater in groupI than in group II (group I, 1·74 ± 37; groupII, 1·19 ±·3, P<0·001). Duringexercise, early diastolic filling was unchanged in normal subjectsbut decreased in patients, with a significant decrease in E/Lindex of 34% (P < 0·001). Thus, pulsed Doppler echocardiography provides a useful methodfor assessing noninvasively exercise-induced changes in leftventricular diastolic filling dynamics in patients with coronaryartery disease.     

Left ventricular response to exercise in aortic stenosis: an exercise echocardiographic study

BACKGROUND: While normal at rest, left ventricular (LV) systolic function may become abnormal during exercise in patients with aortic stenosis. Once contraindicated in patients with aortic stenosis, exercise testing is now recommended in asymptomatic patients with aortic stenosis to elicit symptoms and thereby ascertain the need for aortic valve replacement. However, the clinical significance of an abnormal LV response to exercise in asymptomatic patients with aortic stenosis remains unknown. OBJECTIVE: The aim of this study was to evaluate the clinical implications of an abnormal LV response during exercise in the setting of aortic stenosis. METHODS: We monitored the LV response to exercise by 2D-Doppler echocardiography during a symptom limited semirecumbent bicycle exercise in 50 patients with tight aortic stenosis (aortic valve area < or = 1.0 cm(2)) and a normal LV systolic function (LV ejection fraction, EF > or = 50%) and followed them for an average of 11 months. RESULTS: Twenty patients had an abnormal LV response to exercise with a mean decrease in LV EF from 64 +/- 10 to 53 +/- 12% while 30 patients had a normal LV response to exercise with a mean increase in LV EF from 62 +/- 7 to 70 +/- 8%. Patients with an abnormal LV response during exercise were more likely to develop symptoms during exercise than patients with a normal LV response: 80% versus 27% (P< 0.0001). The survival free of cardiac events was significantly lower in patients with abnormal LV response to exercise than in patients with a normal response (P = 0.03). CONCLUSION: Exercise echocardiography provides objective data that facilitate interpretation of exercise elicited symptoms in asymptomatic patients with severe aortic stenosis. In addition, an abnormal LV response to exercise may predict a poor outcome.