Two dimensional echocardiographic evaluation of exercise-induced left and right ventricular asynergy: correlation with thallium scanning

Two-dimensional echocardiographic evaluation of ventricular asynergy induced by dipyridamole: correlation with thallium scanning

Myocardial asynergies detected by two-dimensional echocardiography during intravenous administration of Dipyridamole (0.75 mg/kg) were evaluated in 54 patients referred for angiographic evaluation of chest pain. Technically adequate two-dimensional echocardiograms suitable for analysis were recorded in 42 of 54 (77.7%) patients studied. Thallium-201 myocardial perfusion scintigraphy, during dipyridamole test was performed in the same patients. Thirty of the 42 patients studied showed significant coronary narrowing at cardiac catheterization. Dipyridamole-induced wall motion abnormalities and myocardial perfusion defects were detected, respectively, in 19 (63.3%) and 21 (70%) of 30 patients with significant coronary artery disease. Wall by wall comparison of the distribution of dipyridamole-induced echocardiographic asynergy with reversible thallium-201 (201Tl) perfusion defects demonstrated complete correlation in 42 segments examined. Three segments with perfusion defects at thallium scanning did not show asynergy during the test while two segments showing wall motion abnormalities during dipyridamole infusion did not manifest perfusion defects. Our study demonstrates that two-dimensional echocardiography during dipyridamole testing is useful in detecting patients with coronary artery disease. Furthermore, ventricular asynergies detected during the test show a high correspondence with site of myocardial perfusion defects at thallium scanning.

Identification of impaired metabolic reserve by atrial pacing in patients with significant coronary artery stenosis

We investigated myocardial 11C-palmitate clearance kinetics at a resting heart rate (control) and during pacing using positron-emission tomography in 10 patients with significant coronary artery stenosis (greater than 70%) and evidence of exercise-induced ischemia. Serial 11C-palmitate images acquired at control and during pacing revealed biexponential myocardial 11C clearance both in myocardium supplied by a stenotic coronary artery (myocardium "at risk") and in myocardium supplied by a normal coronary artery (normal myocardium). At control, the average rate of myocardial 11C clearance from the early rapid curve component (the clearance half-time) was similar in normal myocardium and in that at risk (22.2 +/- 5.2 vs 21.0 +/- 5.4 min, NS), as was the amount of myocardial 11C activity at the end of the early rapid phase (residual fraction 56.3 +/- 7.2% vs 54.7 +/- 7.3%, NS). Thus, myocardial clearance was homogeneous at control, suggesting a similar rate and amount of 11C-palmitate oxidation in normal myocardium and in that at risk. Pacing shortened clearance half-times and decreased residual fraction in both normal myocardium and that at risk compared with control. However, clearance half-times were 17% longer and residual fractions 14% higher in myocardium at risk compared with normal myocardium (p less than .005 and p less than .01, respectively). Therefore, during pacing myocardial 11C clearance became heterogeneous, suggesting impaired 11C-palmitate oxidation in myocardium at risk compared with normal myocardium. Increased substrate utilization in response to increased workload can be thought of as a measure of metabolic reserve. Our data suggest metabolic reserve for free fatty acid oxidation is impaired in myocardium supplied by a significantly stenosed coronary artery and that this impairment can be detected by analysis of myocardial 11C-palmitate clearance.

Use of the epinephrine test in diagnosis of coronary artery disease

Two-dimensional echocardiographic (2-D echo) and electrocardiographic (ECG) monitoring was performed in 53 patients with anginal chest pain during infusion of physiologic doses of epinephrine. Technically adequate 2-D echo studies were recorded in 45 patients. Of these 45 patients, 35 had significant coronary artery disease. Twenty-two patients showed ECG changes during the test (ECG sensitivity 63%), 13 of whom also showed wall motion abnormalities (2-D echo sensitivity 48.5%). Combined ECG and 2-D echo criteria of a positive test yielded a sensitivity of 74%. None of the 10 patients without coronary artery disease had electrical or mechanical abnormalities during the test (specificity 100%). Thus, the epinephrine test during simultaneous 2-D echo and ECG monitoring is a valid alternative to echocardiographic exercise stress testing. Furthermore, the adequate images obtained during the infusion allow better investigation of relation between wall motion abnormalities and ECG changes during myocardial ischemia.

Comparison of postexercise and transesophageal atrial pacing two-dimensional echocardiography for detection of coronary artery disease

Two-dimensional (2-D) echocardiography during transesophageal atrial pacing (TAP) was recently proposed as an alternative to exercise 2-D echocardiography for the diagnosis of coronary artery disease (CAD). To compare these 2 methods, 78 consecutive patients with good-quality echocardiographic (echo) examinations at rest were studied. Two-dimensional echocardiography was performed immediately after supine bicycle exercise and at peak atrial pacing obtained with transesophageal atrial stimulation. Twenty patients were excluded: 16 because of poor quality of 2-D echo images after exercise and 4 because of inadequate TAP studies (atrial capture not achieved in 2 and intolerance in 2). Of the remaining 58 patients, 39 had significant CAD (at least 75% diameter stenosis of at least 1 major coronary artery) and 19 had no significant CAD. The 2 test responses were considered positive if a wall motion abnormality was detected during pacing or after exercise. Sensitivity and specificity were 82% and 95% after exercise and 90% and 84% during TAP. In patients with significant CAD but without wall motion abnormalities at rest, sensitivity was 75% during pacing and 56% after exercise. In patients with significant CAD, the wall motion score index decreased significantly with both types of stress; during pacing wall motion score index was significantly lower than after exercise. Thus, 2-D echo during TAP appears to be a feasible and reliable alternative to postexercise echo for the detection of CAD.

Usefulness of two-dimensional exercise echocardiography shortly after myocardial infarction

To determine the clinical significance of transient remote asynergy after the first acute myocardial infarction (AMI), 2-dimensional echocardiography was performed at rest and directly after dynamic exercise in 49 consecutive patients within 3 weeks of AMI. In 43 patients (88%), technically adequate 2-dimensional echocardiographic examinations were obtained. Asynergy was found in all patients at rest. Immediately after exercise, new areas of asynergy, not adjacent to the infarcted area (i.e., transient remote asynergy), were present in 18 patients. Of these patients, 17 had multivessel coronary artery disease (CAD), compared with 5 of 25 patients without transient remote asynergy. Sensitivity of transient remote asynergy for detecting multivessel CAD was 77% and specificity was 95%. Left ventricular ejection fraction at rest and after exercise was measured in 39 patients (90%) and could only identify patients with 3-vessel CAD. New ischemic events, defined as reinfarction or recurrent angina pectoris, within a mean of 12 weeks (range 8 to 16) after discharge, occurred in 16 patients. Transient remote asynergy was present in 12 of these patients (75%). It is concluded that exercise-induced transient remote asynergy early after AMI can identify patients with multivessel CAD and a subgroup of patients prone to early new ischemic events. Left ventricular ejection fraction, however, is not only more laborious but also of lesser value in identifying patients with multivessel CAD.

Detection of coronary artery disease by two-dimensional echocardiography and transesophageal atrial pacing

Two-dimensional echocardiography was performed at rest and during rapid transesophageal atrial pacing in 85 patients undergoing coronary arteriography for evaluation of chest pain. Transesophageal atrial pacing was performed with 10 ms pulses of 6 to 27 mA intensity; the rate was progressively increased up to 150 beats/min. Four patients were excluded: two because atrial capture was not achieved and two because of chest discomfort induced during transesophageal atrial pacing. Of the remaining 81 patients, 56 had significant coronary artery disease (greater than or equal to 75% stenosis of at least one major coronary vessel) and 25 had no significant coronary artery disease; 25 of the 56 patients with coronary artery disease had no wall motion abnormalities at rest. The test was considered positive if wall motion abnormalities were detected during pacing. Wall motion abnormalities occurred in 3 of 25 patients without coronary artery disease (specificity 88%) and in 51 of 56 patients with coronary artery disease (sensitivity 91%). Wall motion abnormalities developed in 20 of the 25 patients with coronary artery disease and normal regional wall motion at rest (sensitivity 80%); sensitivity for one, two and three vessel disease was 85% (17 of 20 patients), 94% (15 of 16 patients) and 95% (19 of 20 patients), respectively. In patients without coronary artery disease, wall motion score was 18 at rest and 17.7 +/- 0.9 during pacing (p = NS). In patients with coronary artery disease, wall motion score decreased from 15.2 +/- 3.6 at rest to 11.6 +/- 4.1 during pacing (p less than 0.001). In patients with coronary artery disease and normal regional wall motion at rest, wall motion score decreased from 18 at rest to 14.4 +/- 3.1 during pacing (p less than 0.001). Thus, two-dimensional echocardiography during transesophageal atrial pacing appears both sensitive and specific in detecting patients with coronary artery disease. This new procedure is a feasible and reliable alternative to exercise two-dimensional echocardiography.

Transient myocardial ischemia with minimal electrocardiographic changes: an echocardiographic study in patients with Prinzmetal's angina

Kn patients with Prinzmetal's angina, episodes of transient T wave abnormalities (T abn) are often documented in addition to the typical episodes of ST segment elevation (ST). As the interpretation of these minor ECG changes is still uncertain, we investigated if transient T abn are associated with reversible ventricular asynergies, similar to episodes with ST. For this purpose an ECG lead and a two-dimensional echocardiographic projection, which showed clear-cut changes during previous episodes of ST, were simultaneously monitored in five patients with Prinzmetal's angina for a total of 13 hours and 20 minutes. In all patients, the 30 episodes of ST recorded were all accompanied by reversible ventricular asynergies. Furthermore, in four of these patients, 14 episodes of T abn (peaking, flattening, or the appearance of a diphasic T wave) were recorded. All T abn were associated with reversible asynergies, as detected by three independent observers. The mechanical impairment occurred in the same ventricular wall both during ST and during T abn. During T abn the degree of mechanical impairment appeared less severe (hypokinesia in 12 and akinesia in two episodes) than during ST (hypokinesia in one, akinesia in 25, and dyskinesia in four episodes) (p less than 0.001). The duration of asynergies was less during T abn (107 +/- 76 seconds) than during ST (169 +/- 83 seconds) (p less than 0.05). Chest pain was reported in 5 of 14 episodes of T abn (36%) and in 20 of 30 (66%) episodes of ST (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise two-dimensional echocardiography for diagnosis of coronary artery disease

To improve ultrasound images during exercise 2-dimensional echocardiography (2-D echo), a device was developed to hold the transducer and maintain its orientation relative to the heart. The value of this technique in detecting wall motion abnormalities and changes in ejection fraction was evaluated in 54 men undergoing stress test for angina. Thallium-201 scanning, electrocardiography and exercise 2-D echo were recorded concurrently. Technically satisfactory echo studies were obtained in 47 patients (87%). The sensitivity and specificity of exercise echo in the detection of myocardial ischemia as judged by wall motion abnormalities were 100% and 93%, respectively. Sixteen patients with normal thallium scans increased their ejection fraction (EF) estimated by echo (from 52 +/- 1% at rest to 67 +/- 1% at maximal exercise, p less than 0.001); all showed an increase of 5% or more. In contrast, 11 patients who had reversible thallium scan defects showed a consistent decrease in EF (from 53 +/- 2% at rest to 43 +/- 2% during exercise, p less than 0.001); 20 patients with irreversible thallium scan defects showed no specific trend in the EF (48 +/- 2% at rest and 50 +/- 2% during exercise, difference not significant). Changes in heart rate and blood pressure did not distinguish the 3 groups of patients. Our technique of exercise 2-D echo may be useful for detecting wall motion abnormalities and EF changes during exercise and possibly enhance the sensitivity of thallium scanning in the noninvasive diagnosis of coronary artery disease.

Stress echocardiography with transesophageal atrial pacing: preliminary report of a new method for detection of ischemic wall motion abnormalities

We performed two-dimensional echocardiography in 19 patients with significant coronary artery disease and in six normal volunteers at rest and during transesophageal atrial pacing. Technically adequate resting echocardiograms were obtained in 18 of the 19 patients and in all six normal volunteers. In two subjects, atrial capture was not possible, and in one subject, discomfort from the pacing at the beginning of the study precluded its completion. In all subjects (n = 21) who completed the protocol satisfactory two-dimensional echocardiograms were obtained during pacing. Wall motion was normal at rest and during atrial pacing in five normal volunteers. New transient wall motion abnormalities developed in 13 of the 16 patients during pacing. Twelve of the 13 patients had significant coronary lesions in the coronary arteries supplying the abnormal wall segment. Only three of the patients developed significant ST segment depression during pacing. We conclude that stress echocardiography with transesophageal atrial pacing is safe and practical and can be used in patients who cannot perform dynamic exercise, this technique can detect ischemic segmental wall motion abnormalities corresponding to the distribution of coronary arterial obstruction, and the technique provides high-quality echocardiographic images during stress and thus may expand the usefulness of resting two-dimensional echocardiography in patients who have ischemic heart disease.

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

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

A practical approach to exercise echocardiography: immediate postexercise echocardiography

Echocardiographic measurements of left ventricular end-systolic dimension and fractional shortening obtained in the supine position before and immediately after maximal upright exercise were evaluated in 11 normal volunteers, 35 patients with coronary artery disease and 17 patients without coronary artery disease. The time course of recovery from acute exercise-induced changes in echocardiographic dimensions was analyzed using serial postexercise recordings from normal subjects. An exercise-induced decrease in end-systolic dimension (greater than or equal to 3 mm) and increase in fractional shortening (greater than or equal to 5%) persisted for 3 minutes or longer in the immediate postexercise period in each of the normal volunteers. With these criteria to separate normal from abnormal responses, abnormal responses were observed in 16 (94%) of 17 patients with coronary artery disease and in only 2 (6%) of 35 patients without coronary artery disease. Immediate postexercise echocardiography appears to be a practical and potentially valuable adjunct in the detection of coronary artery disease.

Cold pressor test during two-dimensional echocardiography: usefulness in detection of patients with coronary disease

We assessed the feasibility and value of the cold pressor test (CPT) during real-time two-dimensional echocardiography (2DE) in patients with suspected coronary artery disease and normal resting left ventricular wall motion. Twenty patients were studied without knowledge of angiographic findings that demonstrated no significant coronary artery disease in seven (group 1) and significant coronary lesions in 13 (group 2). The increments in physiologic parameters (heart rate, systolic blood pressure, and double product) were not significantly different in both groups. CPT-induced wall motion abnormalities were identified echocardiographically in nine patients in group 2 and in one patient in group 1 (sensitivity 69% and specificity 86%). None of the patients in our study developed chest pain, ST changes, or ectopy during the test. It is concluded that 2DE combined with the CPT is valuable in identifying patients with coronary artery disease who show no left ventricular asynergy at rest.

Two-dimensional echocardiographic studies during sustained ventricular tachycardia

We evaluated left ventricular function in patients with recurrent sustained ventricular tachycardia (VT) using two-dimensional echocardiography (2DE). Thirteen patients, 11 men and 2 women, age range 42-77 (mean 62 +/- 12) years were studied in sinus rhythm (SR) and immediately after VT induction. 2DE parameters analyzed included wall motion, mitral valve leaflet motion, and ejection fraction (EF). In SR, 21 segments/walls in 12 patients showed wall motion abnormalities (WMA) ranging from hypokinesis to dyskinesis and one patient had generalized LV hypokinesis. In VT, new WMA were noted in 2 patients. Thirteen segments/walls in 8 patients showed further worsening of pre-existing WMA. In 1 patient there was worsening of generalized LV hypokinesis. Three patients showed apparent improvement in pre-existing WMA during VT. In 2 patients large apical aneurysms showed a reduction of dyskinesis in VT. Mitral valve opening was intermittent in patients with shorter VT cycle lengths and was maximal when atrial systole preceded or coincided with ventricular depolarization. Doppler echocardiography in 1 patient confirmed the pattern of intermittent mitral flow, with greatest flow occurring when mitral valve opening occurred well before the QRS peak. In 5 patients, 2DE permitted EF measurements. EF in SR ranged from 24-56% (mean 36 +/- 13), decreased to 6-33% (mean 21 +/- 11) within the first ten beats of VT and 6-25% (mean 19 +/- 8) after twenty beats of VT. EF decreased more in patients with shorter VT cycles as compared to those with longer VT cycle lengths.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise echocardiography: a clinically practical addition in the evaluation of coronary artery disease

There has been only modest clinical interest in exercise echocardiography because of the technical limitations of the procedure. Recognizing that there have been recent technical advances in the echocardiographic instruments and that echocardiography should, in theory, be an ideal technique for evaluating exercise-induced wall motion abnormalities, a clinically practical method of performing exercise echocardiograms was developed. By obtaining the echocardiograms immediately after treadmill exercise, with the patient sitting at the treadmill, a high percent of studies adequate for interpretation was obtained (92%). The addition of echocardiography to the treadmill exercise test significantly enhanced the diagnostic yield. In addition, in cases of one and three vessel disease, exercise echocardiography identified stenosis in specific coronary arteries. In patients with two vessel disease and left circumflex obstruction, specific vessel identification was less reliable. A high percent of patients with multivessel disease developed wall motion abnormalities with exercise that persisted for at least 30 minutes. It is concluded that echocardiography performed immediately after exercise with the new generation of echocardiographs can be a practical and useful clinical tool.

Diagnosis of coronary stenosis by two-dimensional echographic study of dysfunction of ventricular segments during and immediately after pacing

The adequacy of two-dimensional echocardiography during right atrial pacing for the detection and characterization of coronary artery stenosis was examined in 10 closed chest dogs. Pacing at successively higher rates up to 210 beats/min was carried out in the control state and again during a 70% left anterior descending coronary artery stenosis-induced with intracoronary plugs. Left ventricular short-axis echographic cross sections were obtained at several levels of the left ventricle. After computer-aided standardized subdivision, contractile function of the global section and its subsegments was characterized by computed systolic fractional area change percent and wall thickening percent. Ventricular segments supplied from the site of the 70% coronary stenosis were delineated in a low papillary level cross section by a myocardial contrast echographic technique, and these segments demonstrated significant dysfunction during pacing at 150 to 210 beats/min. Echographic observation of the involved segments immediately after pacing revealed a maximal depression of function 5 seconds after pacing, equivalent to dysfunction at peak pacing, with function returning to control levels within about 2 minutes. Both maximal pacing and early postpacing studies facilitated satisfactory discrimination of ischemic from normally perfused myocardial segments. These experiments show that right atrial pacing study with quantitative two-dimensional echocardiography may serve to detect and assess a coronary stenosis associated with minor or no cardiac dysfunction in the rest state.

Detection of coronary artery disease with exercise two-dimensional echocardiography. Description of a clinically applicable method and comparison with radionuclide ventriculography

Two-dimensional echocardiography (2-D echo) was performed in 73 patients evaluated for coronary artery disease (CAD) and in four normal volunteers before and immediately after a maximal treadmill exercise test. Diagnostic images were obtained from the apical and parasternal windows. In 17 patients with normal coronary arteriograms, ejection fraction (EF) increased from 66 +/- 9% (+/- SD) at rest to 73 +/- 8% after exercise (p less than 0.001), while in 56 patients with proved CAD, EF fell from 56 +/- 13% at rest to 53 +/- 16% after exercise (p less than 0.01). The sensitivity of postexercise 2-D echo for detecting CAD (based on abnormal EF response and/or regional dyssynergy) was 91% (51 of 56 patients) and the specificity was 88% (15 of 17). Sensitivity for one-, two- and three-vessel disease was 64% (seven of 11), 95% (20 of 21) and 100%, respectively. Patients with multivessel disease showed a significant fall in a wall motion score index, from 0.79 +/- 0.25 to 0.63 +/- 0.26. Exercise radionuclide ventriculography (RNV) was also performed in 41 of the subjects (17 normals and 24 CAD patients) on a bicycle ergometer. The overall sensitivity of 2-D echo in this subgroup was 92%, compared with 71% for RNV. The sensitivity of 2-D echo for one-vessel disease (n = 4) was 50%, that for two-vessel disease (n = 12) was 100% and that for three-vessel disease (n = 12) was 100%. Respective values for RNV were 0%, 80% and 90%. The specificity of 2-D echo was 88% and that of RNV was 82%. A significantly higher peak heart rate response was observed on the treadmill than on the bicycle ergometer in both CAD patients and normal subjects. We conclude that postexercise 2-D echo is a clinically applicable technique for the diagnosis and evaluation of CAD patients and compares favorably with exercise RNV.

Improvement of resting myocardial asynergy with cessation of upright bicycle exercise

Exercise generally aggravates ischemic myocardial dysfunction, presumably by increasing tissue oxygen demand out of proportion to the increase in supply. Nevertheless, resting left ventricular (LV) wall motion abnormalities can improve dramatically after upright exercise. To investigate this "paradoxical" phenomenon, we performed upright bicycle exercise equilibrium radionuclide ventriculography in 93 patients with angiographic coronary artery disease. Immediately after exercise, LV end-diastolic volume was similar to the resting level (1 +/- 22% of rest value), but end-systolic volume (ESV) was significantly below (p less than 0.05) that at rest (-11 +/- 32%) and LV ejection fraction increased significantly compared with rest (0.57 +/- 0.16 vs 0.51 +/- 0.13, p less than 0.05). Improvement in resting myocardial asynergy was frequent (115 of 330 abnormal segments), and was observed more commonly in patients without pathologic Q waves and in segments manifesting mild rather than severe asynergy. In 60 additional patients with resting asynergy who were also studied after nitroglycerin (NTG), there was 89% concordance of wall motion response in asynergic segments after exercise and NTG: 71 of 85 segments manifesting improvement with NTG also improved after exercise, and 157 of 172 segments without improvement with NTG also failed to improve after exercise. Despite the similar wall motion response, the mechanism of improvement is probably different from that produced by NTG. With NTG, preload (end-diastolic volume) and afterload (systolic blood pressure) were significantly lower than their resting control levels (p less than 0.05). These changes did not occur after exercise. Instead, an isolated, significant reduction in ESV was noted. These data support the hypothesis that catecholamine stimulation is responsible for paradoxical wall motion improvement after upright exercise.

Segmental right ventricular function after acute myocardial infarction: two-dimensional echocardiographic study in 63 patients

Right ventricular (RV) segmental contraction was studied in 63 patients with acute myocardial infarction (MI), using 2-dimensional (2-D) echocardiography. Group A included 32 patients with ischemic RV dysfunction: 19 had a disproportionate increase in right atrial pressure at the time of the examination (Group AI) and in 13 patients, right atrial pressure was normal when the echocardiogram was obtained (Group AII). Group B included 31 patients without ischemic RV dysfunction. Alkinesia or dyskinesia of the RV wall was found in 30 patients: 19 from Group AI, 8 from Group AII, and 3 from Group B. Asynergy could be identified in all segments of the RV wall including the outflow tract, RV apex, and anterior wall, but was more frequently found in the posterior wall (29 patients), best seen in the transversal subcostal short-axis view. A significant difference was found either in the frequency of wall motion abnormalities or in the number of segments with asynergy among the 3 groups (p less than 0.001). However, asynergy of the RV wall may be present in some patients with normal right heart hemodynamic function, suggesting that asynergy may be more sensitive than hemodynamic function in the diagnosis of acute RV infarction. Paradoxical septal motion was found in 8 patients, all in Group AI, and all had a right atrial pressure equal to or greater than pulmonary capillary pressure.

Exercise 2-dimensional echocardiography. Quantitation of left ventricular performance in patients with severe angina pectoris

To assess the feasibility and reproducibility of exercise 2-dimensional (2-D) echocardiography for quantitating left ventricular size and performance, 25 patients with angina pectoris due to severe coronary artery disease and 10 normal subjects were studied before and after the administration of nitroglycerin. In 18 (72%) of the 25 patients, suitable biapical 2-D echocardiograms for quantitative analysis were recorded during upright bicycle exercise. Left ventricular volume (Simpson's rule), ejection fraction (EF), and wall motion score (10 segments graded 0 to 3, normal to dyskinetic) were measured at rest, and at peak exercise (control), 30 minutes later at rest, after nitroglycerin at rest, and at peak exercise. EF increased during control exercise in the normal subjects from 57 +/- 16 to 71 +/- 22% (p less than 0.01), but was unchanged in the patients during exercise before nitroglycerin. In 7 patients (39%), marked increases in EF (greater than 0.05 units) during exercise occurred after nitroglycerin administration. The wall motion score increased significantly in the patients during control exercise, from 2.6 +/- 3.4 to 5.6 +/- 4.5, but was less at maximal exercise after nitroglycerin (3.4 +/- 4.0, p less than 0.001). Intra- and interobserver variability in these measurements was acceptable. Thus, quantitation of left ventricular performance during exercise by biapical 2-D echocardiography can be accomplished in a high proportion of patients with coronary artery disease (CAD) and can be used to assess the effects of therapeutic interventions.

Echocardiography: an overview

In the past 25 to 30 years echocardiography has become a basic examination in clinical cardiology. Thus, it is becoming increasingly necessary for clinicians to be able to utilize it intelligently. Like all medical procedures echocardiography has advantages and limitations, and physicians need to know both. Some of the limitations are being minimized with advances in examination techniques and instrumentation, but many still exist. One limitation is that the ability to satisfactorily educate and train persons in the various ultrasonic techniques has not kept pace with the worldwide popularity of the examination. As a result, quality control will remain a problem at least in the immediate future. New developments in echocardiography as invasive and noninvasive tools are exciting and indicate that ultrasonic examination of the heart should play an increasingly important role in clinical cardiology.