Right and left ventricular dysfunction in patients with chronic obstructive lung disease: Assessment by first-pass radionuclide angiography

To evaluate the relationship between right and left ventricular function in patients with obstructive lung disease, we studied 10 normal subjects (group 1) and 37 patients with chronic obstructive pulmonary disease by first pass radionuclide angiography. These 37 patients were divided into three groups: nine with mild chronic obstructive pulmonary disease (group 2), 20 with severe chronic obstructive pulmonary disease (group 3) and eight with severe chronic obstructive pulmonary disease and primary left ventricular disease (group 4). In each subject right ventricular ejection fraction (RVEF), left ventricular ejection fraction (LVEF) and ejection fraction during first third of systole (first third LVEF) were calculated. LVEF RVEF First-Third LVEF Group 1 0.60 ± 0.05 0.52 ± 0.03 0.29 ± 0.04 Group 2 0.61 ± 0.08 0.52 ± 0.03 0.29 ± 0.02 Group 3 0.58 ± 0.09 0.46 ± 0.091 0.24 ± 0.061 Group 4 0.51 ± 0.061 0.44 ± 0.091 0.20 ± 0.031 1 p < 0.05 versus 1. All subjects in group 2 had normal left ventricular and right ventricular function. In group 3,11 of 10 (55 per cent) had a low RVEF and three of 20 (15 per cent) a low LVEF. However eight of 20 in this group (40 per cent) had a depressed first-third LVEF. The correlation between decline in RVEF and first-third LVEF was good r = 0.73. We conclude that (1) certain indices of early systolic left ventricular ejection are abnormal in many patients with chronic obstructive pulmonary disease and correlate with the decline in right ventricular function; (2) this is not seen in patients with mild chronic obstructive pulmonary disease and is worse in patients with underlying left-sided heart disease.     

Assessment of right ventricular function at rest and during exercise in patients with coronary heart disease: A new approach using equilibrium radionuclide angiography

To evaluate a new method of calculating right ventricular ejection fraction by equilibrium radionuclide angiography and to assess its response during supine bicycle exercise, 20 normal persons and 50 patients with angiographically documented coronary artery disease were studied. Each subject underwent a resting equilibrium and first pass right ventricular study as well as symptom-limited graded bicycle exercise while supine. The correlation between the two methods in all 70 cases was good (r = 0.81). Inter- and intraobserver variability was small (3.9 ejection fraction units or less) and serial reproducibility (two studies performed 2 weeks apart) was also good (4 ejection fraction units or less). There was no difference in the right ventricular ejection fraction at rest when normal subjects and patients with coronary disease were compared (0.49 ± 0.10 versus 0.46 ± 0.08). Ejection fraction increased with exercise in normal subjects (0.49 ± 0.10 to 0.64 ± 0.12, p < 0.005). As a group, patients with right coronary stenosis (alone or in combination with other lesions) showed no change in ejection fraction with exercise (0.46 ± 0.13 to 0.45 ± 0.12); and ejection fraction increased with exercise in patients with coronary disease without right coronary stenosis (0.46 ± 0.08 to 0.53 ± 0.11, p < 0.05). Among patients with both significant right and left coronary artery disease more severe right ventricular dysfunction during exercise was seen in the presence of more severe left ventricular dysfunction. It is concluded that during exercise the right ventricle shows dysfunction caused in part by local ischemia as well as by altered loading conditions due to left ventricular dysfunction. Equilibrium angiography is a useful and reliable method for evaluating right ventricular function in man.     

Effect of sublingual nitroglycerin on left ventricular function at rest and during spontaneous angina pectoris: Assessment with a radionuclide approach

Left ventricular function and size were assessed with equilibrium radionuclide angiography at rest and after administration of 0.6 mg of sublingual nitroglycerin in 12 patients with a history of previous myocardial infarction. Spontaneous angina developed in five patients and seven patients had no pain at the time of study. Sequential ejection fractions and end-diastolic and end-systolic volumes were developed by summing multiple R-R intervals to produce a composite time-activity curve. Volumes were calculated with a nongeometric method that utilizes counts at end-diastole and end-systole and is corrected for total heartbeats and plasma radioactivity. In the patients without acute ischemia, peak increase in ejection fraction occurred 6 to 8 minutes after ingestion of nitroglycerin and was associated with an equal decrease in end-diastolic and end-systolic volumes with no change in stroke volume. End-diastolic and end-systolic volumes, stroke volume, heart rate and systolic blood pressure all returned to baseline levels by 1 hour after nitroglycerin. In the patients with spontaneous angina, ejection fraction and stroke volume decreased before pain occurred. End-diastolic volume increased slightly (7 percent), but end-systolic volume increased markedly (38 percent), thus explaining the decrease in stroke volume. After nitroglycerin, end-diastolic volume and end-systolic volume and systolic blood pressure decreased and stroke volume and ejection fraction increased. Improvement in function occurred before relief of pain.

It is concluded that the action of nitroglycerin on the left ventricle in patients without acute ischemia is to increase ejection fraction by an equal decrease in end-diastolic and end-systolic volumes with little change in stroke volume. A reduction in left ventricular function during acute ischemia precedes complaints of pain and is associated with an increase in end-systolic and end-diastolic volumes and a decrease in ejection fraction and stroke volume. In these patients, nitroglycerin appeared to contribute to relief of pain by decreasing end-diastolic volume and systolic blood pressure.     

Peak systolic blood pressure/end-systolic volume ratio: Assessment at rest and during exercise in normal subjects and patients with coronary heart disease

To assess the utility of a recently proposed index of left ventricular performance, the ratio of peak left ventricular systolic pressure to end-systolic volume, equilibrium radionuclide angiography was used to determine end-systolic volume and the systolic blood pressure obtained by cuff sphygmomanometer to determine peak systolic pressure. Data were analyzed at rest and during supine bicycle exercise in 15 normal subjects (Group 1), 50 patients with coronary artery disease (Group II) and 9 patients with obstructive lung disease and no evidence of coronary artery disease on clinical examination including exercise thallium imaging (Group III). In 15 subjects the correlation between the resting angiographic and radionuclide pressure/volume ratio was excellent (r = 0.929, p <0.005).Forty-seven (94 percent) of the 50 patients in Group II had a depressed pressure/volume ratio at rest or an abnormal change in this ratio during exercise, whereas only 43 (86 percent) of this group had an abnormal ejection fraction at rest or during exercise. Additionally, 3 of 15 subjects in Group I had an abnormal ejection fraction response, defined as less than 0.05 ejection fraction unit increase with exercise (specificity 80 percent), whereas all subjects in Group I had a normal increase in pressure/volume ratio (specificity 100 percent). At rest, neither index identified more patients with coronary artery disease than the other. Of the nine patients in Group III, six had an abnormal ejection fraction response to exercise, whereas only one had an abnormal pressure/volume ratio response.It is concluded that the end-systolic pressure/volume ratio is a useful index of left ventricular performance. In some patients during supine exercise stress it may be more sensitive than the ejection fraction response alone in identifying the presence of coronary artery disease.     

Assessment of mitral valve E point-septal separation as an index of left ventricular performance in patients with acute and previous myocardial infarction

A new echocardiographic index of left ventricular function, mitral valve E point-septal separation, was compared with the radionuclide ejection fraction determined using the first pass method in 60 patients (73 studies) with ischemic heart disease. Thirty-eight patients had acute myocardial infarction and 22 patients were studied an average of 24 months after acute infarction. In 30 normal subjects, E point-septal separation ranged from 0 to 5.4 mm (average 1.3 mm). In 57 studies (78 percent) E point-septal separation correctly identified patients with a normal or reduced ejection fraction (less than 0.52), but in 13 studies (18 percent) E point-septal separation was normal and ejection fraction depressed. In only three studies (4 percent) was there a normal ejection fraction and an abnormal E point-septal separation. Results did not differ between patients with acute infarction and those studied late after infarction. An E point-septal separation of more than 5.5 mm was highly specific (92 percent) for a reduced ejection fraction, but the sensitivity rate was only 65 percent. Abnormal wall motion as assessed with echocardiography or videotracking, or both, occurred equally among patients with normal and increased E point-septal separation, but this measure was less accurate in patients with more severe wall motion abnormalities. E point-septal separation was unrelated to heart rate; an abnormal value was equally distributed among patients with a normal and those with an enlarged left ventricular end-diastolic dimension on echocardiography. E point-septal separation was superior to other echocardiographic indexes of left ventricular function (percent of fractional shortening, mean rate of diameter shortening and ejection fraction). Thus, E point-septal separation is a simple noninvasive measure of left ventricular function. We conclude that an abnormal E point-septal separation is useful for identifying depressed left ventricular function in patients with acute myocardial infarction and chronic ischemic heart disease. However, 28 percent of our patients with a normal E point-septal separation had a depressed radionuclide ejection fraction. Therefore a normal value for E point-septal separation does not exclude the presence of abnormal left ventricular function in such patients.     

Sensitivity and specificity of nuclear phase analysis versus ejection fraction in coronary artery disease

Phase standard deviation (SD) and skew characteristics of the first Fourier harmonic of equilibrium radionuclide volume curves were examined and compared during rest and during supine bicycle exercise with ejection fraction (EF) changes and the development of ischemia in 17 control subjects and in 2 groups of patients (n = 57) with coronary artery disease (CAD). Group I comprised 37 patients with CAD; IA was a subgroup of 20 patients with previous myocardial infarction (MI) and IB a subgroup of 17 patients with CAD without MI (all with coronary stenosis greater than 75% diameter narrowing). Group II comprised 20 patients with CAD who had undergone coronary bypass surgery. In the Group I subjects, phase SD was the most sensitive indicator of CAD at rest (Group I, 56%; Group IA, 70%, and Group IB, 29%), and the EF was the most sensitive indicator at submaximal (Group I, 78%; Group IA, 86%, and Group IB, 64%) and maximal exercise (Group I, 70%; Group IA, 93%, and Group IB, 53%). When phase SD and skewness were combined with EF changes, little increase in sensitivity occurred in Group I (rest 61%, submaximal exercise 88% and maximal exercise 76%). The results from Group II subgroups were qualitatively similar to those observed with Group I subgroups. These data reveal a marginally improved sensitivity for detection of CAD during supine bicycle radionuclide ventriculography when phase measurements were added to changes in global EF values.     

Effect of nitrates on left ventricular size and function during exercise: Comparison of sublingual nitroglycerin and nitroglycerin paste

To compare the effects of sublingual nitroglycerin and nitroglycerin paste on left ventricular size and performance during supine bicycle exercise, equilibrium radionuclide angiography was performed in 36 persons classified into two groups of normal subjects and two groups of patients with angiographically proved coronary heart disease. Each group underwent a control exercise study, and then one group of normal subjects and one group of patients were restudied after the administration of 0.6 mg of nitroglycerin or 2 inches (5 cm) of nitroglycerin paste (but not both). Data were collected at rest and at peak exercise.In normal subjects exercise resulted in increased ejection fraction, decreased end-systolic volume and little change in end-diastolic volume. After either drug, volumes at rest markedly decreased, and during exercise, ejection fraction increased to levels comparable with pre-drug levels. After nitroglycerin paste the reduction in volume seen at rest persisted during exercise, but after sublingual nitroglycerin end-diastolic volume increased during exercise (88 ± 43 to 113 ± 30 ml [mean ± standard deviation]; p < 0.01). Peak exercise end-diastolic volume after nitroglycerin was still lower than that before nitroglycerin (113 ± 30 versus 120 ± 28 ml, p < 0.05).In patients with coronary disease, ejection fraction did not change during exercise, but both end-diastolic and end-systolic volumes increased. After either drug ejection fraction at rest was unchanged, although ventricular volumes were markedly lower (p < 0.05). Ejection fraction increased with exercise in both groups with coronary disease after either drug. After sublingual nitroglycerin, volumes increased during exercise although the peak exercise end-diastolic volume was still lower than the control value (113 ± 31 versus 145 ± 34 ml; p < 0.01). After paste administration, end-diastolic volume did not change during exercise, and end-systolic volume decreased (41 ± 20 to 36 ± 22 ml; p < 0.05).Thus, sublingual nitroglycerin and nitroglycerin paste improved left ventricular function during exercise. The effect of paste on end-diastolic volume appeared sustained, whereas that of sublingual nitroglycerin was transient, confirming the hypothesis that reduction in end-diastolic volume and, by implication, left ventricular wall tension, is a major mechanism of nitrate action.     

Serial noninvasive assessment of left ventricular hypertrophy and function after surgical correction of aortic regurgitation.

Serial echocardiographic analyses of left ventricular hypertrophy and function, with validation of extent of shortening by first pass radionuclide angiography, was performed in 16 patients before and after surgical correction of severe aortic valve regurgitation. All patients were symptomatic (predominantly in New York Heart Association functional class III or IV) before operation but were in class I or II after operation. The preoperative pattern of eccentric hypertrophy (increased mass with normal ratio of left ventricular cross-sectional wall area to cavity area) changed immediately after operation to a pattern of concentric hypertrophy (increased mass with increased ratio of left ventricular cross-sectional wall area to cavity area) because of a significant reduction in chamber size and increase in wall thickness. On late follow-up (9 to 35 months, average 15 months after operation), the hypertrophy lessened significantly, the cross-sectional area of the ventricular wall decreasing to 21.1 ± 5.4 (mean ± standard deviation) cm² from a preoperative average of 31.6 ± 4.8 cm² (P < 0.01), and the ratio of wall area to cavity area was once again normal. In the same period, left ventricular enddiastolic diameter decreased from 6.52 ± 0.68 to 4.64 ± 0.52 cm (P < 0.01). Preoperatively, ejection phase indexes were normal or only marginally depressed in 12 of 16 patients but were moderately depressed in the remaining 4. At early follow-up (average 4 months) ventricular shortening tended to increase; and at late follow-up the fractional shortening of the minor axis, the ejection fraction and the mean velocity of circumferential fiber shortening increased to 0.39 ± 0.07, 0.68 ± 0.10 and 1.26 ± 0.22 circumference/sec, respectively, from preoperative values of 0.33 ± 0.09, 0.60 ± 0.14 and 1.05 ± 0.31 circumferences/sec (P < 0.05 for each index). In the four subjects with preoperative depression of left ventricular function, the extent and speed of myocardial shortening at late follow-up became normal in three subjects and remained moderately depressed in one patient. Paradoxical septal motion was observed immediately postoperatively and in the early follow-up studies, but it was noted in only 3 of 16 cases by the late follow-up period. Provided septal dyskinesia was not present, echocardiographic and first pass radionuclide determinations of ejection fraction correlated highly (r = 0.92).It is concluded that when aortic valve replacement for symptomatic aortic regurgitation is undertaken prior to severe myocardial decompensation, improvement in clinical status is associated with significant regression of myocardial hypertrophy, reduction in left ventricular size, evolution of a normal $\text{mass}\text{volume}$ ratio, recovery of septal dyskinesia as revealed on echocardiography, and improvement in left ventricular function. These data do not define the type and degree of left ventricular dysfunction which is irreversible.     

Posterior wall velocity: an unreliable index of total left ventricular performance in patients with coronary artery disease

Posterior wall velocity determined by use of echocardiography has been proposed as an index of total left ventricular performance in patients with ischemic heart disease. Accordingly, in 9 normal subjects and 39 patients with angiographically documented coronary artery disease, we compared mean endocardial posterior wall velocity determined by echocardiography with echocardiographic and biplane cineangiographic calculations of ejection fraction and the mean rate of circumferential fiber shortening (mean V_CF), and with externally recorded systolic time intervals. All studies were performed on the same day in each patient. Mean endocardial posterior wall velocity averaged 4.6 cm/sec (range 2.9 to 8.7) and correlated poorly with echocardiographic ejection fraction (r = 0.47), cineanglographic ejection fraction (r = 0.26), cineangiographic mean V_CF (r = 0.47), the ratio of preejection period to left ventricular ejection time (r = ?0.35) and the preejection period corrected for heart rate (r = ?0.30). Substitution of maximal for mean endocardial posterior wall velocity did not improve the separation of normal from depressed left ventricular performance. Epicardial posterior wall velocity, a measurement more easily obtainable than endocardial posterior wall velocity, also did not correlate well with systolic time intervals or with ejection fraction or mean v_cf derived from the echocardiogram and cineangiogram. Both endocardial and epicardial posterior wall velocity values were poorly reproducible on a day to day or a beat to beat basis. We conclude that neither endocardial nor epicardial posterior wall velocity, whether derived as a mean or a maximum, provides an accurate measure of total left ventricular performance in patients with coronary artery disease.     

Ultrasonic enhancement of myocardial infarction with perfluorocarbon compounds in dogs

Medically pure (100%) carbon dioxide directly injected into a peripheral vein was used for 2-dimensional contrast echocardiography in 134 patients with an arteriovenous shunt demonstrated by cardiac catheterization and cineangiography, Qp/Qs ratios of 1.5 to 3.7, pulmonary-to-systemic peak systolic pressure ratios of 0.2 to 0.8 and no oximetrically demonstrable venoarterial shunt. Two patients with transposition of the great arteries, intact ventricular septum and a Senning operation as well as 30 normal subjects of comparable age also were studied. In patients with an atrial septal defect, the gas microbubbles opacified the left atrium. In patients with a ventricular septal defect, the gas microbubbles opacified the left ventricle, whereas the left atrium was free of contrast. In all patients with patent ductus arteriosus, the gas microbubbles opacified the abdominal aorta, whereas the left atrium, left ventricle, aortic root and aortic arch remained free of contrast. In 2 patients in whom an aneurysm of the sinus of Valsalva ruptured into the right ventricle, the "negative" contrast effect permitted localization of the shunt. In 2 patients with transposition of the great arteries, an intact ventricular septum and a Senning operation, the intracardiac flow pattern was clearly demonstrated. No complication was observed. We conclude that pure carbon dioxide directly injected into a peripheral vein is a safe and advantageous echocardiographic contrast material. Because of its greater diffusibility in comparison with oxygen and fluid contrast media, small venoarterial shunting can be detected in defects such as atrial septal defect, ventricular septal defect and patent ductus arteriosus, in which only an arteriovenous shunt can be demonstrated by oximetry.     

Myocardial infarct size determined by computed transmission tomography in canine infarcts of various ages and in the presence of coronary reperfusion

Thirty-one dogs underwent in vivo scanning with computed transmission tomography; 15 dogs were studied within 7 days (mean 4) after coronary occlusion, 10 dogs 21 to 25 days (mean 28) after occlusion and 6 dogs 4 days after coronary reperfusion of a 2 to 3 hour coronary ligation. Ungated scans (1 cm in depth) of the left ventricle were obtained from apex to base to determine infarct size. In all animals with documented (postmortem) infarction (n = 26), contrast medium caused delayed enhancement of the entire infarct or the periphery of the infarct. Infarct size was calculated from scans showing contrast enhancement of the infarct. Infarct size was also determined from the postmortem heart using histochemical morphometry (nitroblue tetrazolium) and then compared with infarct size derived from tomography using the outer margin of the contrast-enhanced periphery of the infarct as the border of the infarct. Infarct size calculated by the tomographic technique (excluding the animals without an infarct) correlated well with infarct size determined at autopsy (r = 0.90, p less than 0.001). The tomographic estimate (18.2 +/- 11.3 g) of infarct size was similar to autopsy values (18.6 +/- 11.8 g, p = NS). Thus, ungated computed transmission tomographic imaging of the heart can reliably estimate infarct size in a variety of potential clinical circumstances, particularly when the area of rim enhancement of the infarct is included within the presumed infarct region.     

Favorable effects of orally administered digoxin on left heart size and ventricular wall motion in patients with previous myocardial infarction.

The effects of maintenance oral digoxin therapy on segmental left ventricular wall motion (wall motion videotracking) and left heart size (radiographic left heart dimension) were evaluated in 14 patients with a prior myocardial infarction but without clinical signs or symptoms of congestive heart failure. The left heart dimension decreased in all six patients with cardiomegaly from an average of 55.0 +/- 1.6 (standard deviation) to 52.2 +/- 2.7 mm/m2 body surface area (P less than 0.01) during digoxin therapy. However, there was no significant change in the eight patients with normal heart size. In the resting state, the average extent of shortening in normal segments increased significantly from 3.1 +/- 0.8 to 4.2 +/- 1.2 mm during digoxin therapy. During submaximal handgrip exercise, the extent of shortening averaged 4.0 +/- 1.3 mm and increased further with digoxin therapy to 5.1 +/- 2.1 mm. The effects of digoxin therapy on the maximal velocity of shortening in normal segments at rest and during handgrip exercise were similar. In all 14 patients, there was a decrease in the number of segments with abnormal wall motion at rest or with handgrip exercise during digoxin therapy. With therapy, the number of abnormal sites decreased from 52 to 35 in the resting state and from 84 to 49 during handgrip exercise. Thus, in patients 6 or more months after transmural myocardial infarction, orally administered digoxin decreases cardiomegaly, increases the extent and maximal velocity of shortening in normal left ventricular segments and often reduces the extent of abnormal wall motion at rest or during isometric exercise.     

Arm-crank ergometry: a new method for the evaluation of coronary artery disease

We have developed an electrocardiographic stress test to evaluate coronary heart disease using an arm-crank device (modified bicycle ergometer) in patients unable to perform leg exercise. With an initial work load of 200 kg-m/min at 40 revolutions/min for 3 minutes, followed by 100 kg-m/min increments every 3 minutes to a maximum of 700 kg-m/min at the same speed, a linear relation between the increase in heart rate and work load was observed. Twenty-one patients underwent both conventional treadmill exercise (modified Bruce protocol) and arm-crank exercise on separate days. Peak heart rate was slightly slower with arm-crank exercise (81 ± 4 [standard error] vs. 85 ± 3 percent of maximal predicted heart rate for age, P < 0.02) but peak systolic blood pressure and heart rate-systolic blood pressure product (double product) did not differ significantly (157 ± 7 vs. 154 ± 6 mm Hg, P > 0.5) and (22.0 ± 1.2 vs. 22.5 ± 1.2 × 10³, P > 0.1). Ten patients with documented coronary artery disease, including 7 with angina pectoris, had an ischemie S-T segment response (0.08 second depression greater than 1 mm) by both methods and 10 patients (7 with previous myocardial infarction and 3 with normal coronary arteriograms) had negative results by both techniques. One patient with normal coronary arteriograms had a negative arm-crank test and a positive treadmill test. In 26 patients unable to perform leg exercise the mean peak heart rate, systolic blood pressure and double product with arm-crank exercise were not significantly different (P > 0.05) from those achieved by the ambulatory patients (73.2 ± 1.9 vs. 81.0 ± 4.0 percent, 167 ± 8 vs. 157 ± 7 mm Hg and 22.4 ± 1.2 vs. 22.0 ± 1.4 × 10³, respectively). Six of 26 patients unable to perform leg exercise had a positive arm-crank test. Four of these six patients had angina pectoris and three had a previous myocardial infarction. We conclude that arm-crank exercise is comparable to treadmill exercise and is a reliable alternative method for the evaluation of suspected coronary artery disease in patients unable to perform leg exercise.     

Effects of transient coronary ischemia and reperfusion on myocardial edema formation and in vitro magnetic relaxation times

The effects of transient ischemia and reperfusion on regional myocardial function, salvage and swelling have been systematically analyzed in experimental canine preparations. The results of these interventions on myocardial in vitro measurements of magnetic relaxation times (T1 = magnetization recovery, T2 = spin echo) are of significant importance with respect to future nuclear magnetic resonance tomographic imaging. Thus, using a pulsed magnetic resonance spectrometer (10.7 MHz), myocardial tissue samples from two groups of dogs were evaluated. In group 1 (n = six dogs), the left anterior descending artery was occluded for 3 hours before sacrifice; in group 2 (six dogs), 3 hours of occlusion was followed by 1 hour of reperfusion. Multiple tissue samples from normal and ischemic (or ischemic and reperfused) myocardium were obtained for measurement of T1, T2 and % water content (wet weight--dry weight/wet weight). Water content increased with ischemia (78 +/- 4%) and reperfusion (81 +/- 4%) (both p less than 0.01 versus control values). Values for T1 increased with ischemia (598 +/- 39 versus 487 +/- 23 ms in normal tissue from the same heart, p less than 0.01). Even greater T1 changes occurred in the animals with reperfusion (654 +/- 52 ms, p less than 0.01 versus the intra-animal control values). Changes in T2 were similar but less marked (ischemic zone 43.9 +/- 1.0 versus 41.2 +/- 1.0 ms in nonischemic tissue in the corresponding heart, p less than 0.05; reperfusion zone 48.3 +/- 3.5 versus 41.9 +/- 2.3 ms in the normal zone, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of digital intravenous ventriculography with direct left ventriculography for quantitation of left ventricular volumes and ejection fractions

Digital images of the left ventricle obtained at 30 frames/second from continuous fluoroscopy after intravenous injection of contrast medium (digital intravenous Ventriculography) were used to estimate left ventricular (LV) volumes and ejection fraction with use of several techniques for identifying the ventriculographic silhouette. The digital technique was compared with direct contrast left Ventriculography in 26 patients undergoing diagnostic cardiac catheterization. End-diastolic and end-systolic volumes calculated from digital intravenous and direct left ventriculograms were obtained with use of a standard area-length formula. Both end-diastolic volume (EDV) (r = 0.88, y = 1.06x ? 17.1 ml) and end-systolic volume (ESV) (r = 0.89, y = 0.96x + 0.43 ml) determined from digital intravenous ventriculography (mask mode images) correlated closely with those obtained by direct left ventriculography. Combining the EDV and ESV to define the relation between the 2 techniques yielded an even closer correlation (r = 0.96). There was also good correlation between the 2 techniques for measurement of ejection fraction (r = 0.81, standard error of the estimate 6.7%). Measurements from direct left Ventriculography were frequently invalidated by ventricular arrhythmias during the time of opacification of the left ventricle; this was rarely the case for digital intravenous Ventriculography. It is concluded that area-length estimates of LV volumes and ejection fraction can be accurately obtained from digital processing of fluoroscopic LV images after intravenous injection of contrast medium.     

Beneficial effects of nitroglycerin on abnormal ventricular wall motion at rest and during exercise in patient with previous myocardial infarction.

The effects of sublingually administered nitroglycerin on segmental left ventricular wall motion determined by videotracking and radiographic left heart size were evaluated at rest and during submaximal hand grip exercise in 10 patients with previous transmural myocardial infarction. After nitroglycerin, diastolic left heart size decreased in the resting state from an average of 49.5 +/- 5.7 (standard deviation) to 47.9 +/- 5.6 mm/m2 body surface area (P less than 0.01) and during handgrip exercise from a mean of 50.7 +/- 590 to 49.1 +/- 4.7 mm/m2 (P less than 0.05). In the resting state, the average maximal velocity of shortening in segments with normal wall motion increased after nitroglycerin from 18.1 +/- 3.0 to 23.5 +/- 5.5 mm/sec (P less than 0.01), whereas during handgrip exercise alone, the velocity of shortening averaged 25.6 +/- 6.9 mm/sec and increased further after nitroglycerin to 30.1 +/- 10.6 mm/sec (P less than 0.05). The effects of nitroglycerin on the average extent of shortening in normal segments were similar. In all 10 patients, there was a decrease in the number of segments with abnormal wall motion. The number of sites with dyssynergy decreased after nitroglycerin from 24 to 15 in the resting state and from 40 to 22 when nitroglycerin was administered before handgrip exercise. Sublingually administered nitroglycerin appears to decrease left heart size, increase the velocity and extent of shortening in normal left ventricular segments and often reduce the extent of left ventricular wall motion abnormalities at rest and during isometric exercise in patients with previous transmural myocardial infarction.     

Normal left ventricular emptying in coronary artery disease at rest: analysis by radiographic and equilibrium radionuclide ventriculography

The volume ejected early in systole has been proposed as an indicator of abnormal left ventricular function that is present at rest in patients with coronary artery disease with a normal ejection fraction and normal wall motion. The volume ejected in systole was examined by calculating the percent change in ventricular volume using both computer-assisted analysis of biplane radiographic ventriculograms at 60 frames/s and equilibrium gated radionuclide ventriculograms. Ventricular emptying was examined with radiographic ventriculography in 33 normal patients and 23 patients with coronary artery disease and normal ejection fraction. Eight normal subjects and six patients with coronary artery disease had both radiographic ventriculography and equilibrium gated radionuclide ventriculography. In all patients, there was excellent correlation between the radiographic and radionuclide ventricular emptying curves (r = 0.971). There were no difference in the ventricular emptying curves of normal subjects and patients with coronary artery disease whether volumes were measured by radiographic or equilibrium gated radionuclide ventriculography. It is concluded that the resting ventricular emptying curves are identical in normal subjects and patients with coronary artery disease who have a normal ejection fraction and normal wall motion.