sodium-pertechnetate-tc-99m and Aortic-Valve-Insufficiency

To evaluate interventricular septal motion and left ventricular function after aortic valve replacement for chronic aortic regurgitation, we studied 12 patients at rest and during exercise by radionuclide angiography after a mean of 19 (range 12-36) months after operation (group I). Twenty patients with chronic aortic regurgitation without aortic valve replacement served as controls (group II). None of the patients had coronary artery disease as documented by arteriography. Abnormal interventricular septal motion at rest was seen in 11 patients of group I, of whom 8 showed hypokinesis and 3 akinesis. During exercise, the interventricular septal wall motion improved in 4 patients, worsened in 3 patients and did not change in 5 patients. All patients of group II had normal interventricular septal motion at rest. During exercise, 5 patients showed septal wall hypokinesia together with apical and posterolateral wall motion abnormalities. The left ventricular ejection fraction at rest was 62% +/- 20% in group I and 66% +/- 8% in group II (not significant). During exercise, the left ventricular ejection fraction was 59% +/- 24% in group I and 68% +/- 13% in group II (not significant). We conclude that abnormal interventricular septal motion at rest is commonly found in patients with aortic valve replacement for chronic aortic regurgitation. During exercise, septal wall motion in the patients with aortic valve replacement shows a variable response from complete normalization to akinesia. These findings are mostly associated with a normal global left ventricular function both at rest and during exercise, which precludes myocardial ischaemia as a primary cause for abnormal septal wall motion after aortic valve replacement.

Topics: Adult; Aortic Valve Insufficiency; Erythrocytes; Exercise Test; Female; Gated Blood-Pool Imaging; Heart Septum; Heart Valve Prosthesis; Humans; Male; Myocardial Contraction; Sodium Pertechnetate Tc 99m; Ventricular Function, Left

We compared M-mode echocardiographic and gated equilibrium radionuclide angiography assessment of the left ventricular (LV) dimensions at rest and during isometric exercise in 18 patients with chronic aortic valve incompetence. The two methods showed a satisfactory correlation when comparing LV size at rest and during exercise (LV end-diastolic dimension in echocardiography vs LV end-diastolic volume in radionuclide angiography, r = 0.80, P less than 0.01 at rest and r = 0.81, P less than 0.01 at rest and r = 0.75; P less than 0.01 during exercise), but fractional shortening in echocardiography and ejection fraction in radionuclide angiography did not correlate (r = 0.27, not significant (NS) at rest and r = 0.34, NS during exercise). Thus echocardiography and radionuclide angiography describe LV dimensions at rest and during handgrip exercise in a similar fashion, documenting the concordance of these noninvasive methods to describe LV size in aortic incompetence at rest and during exercise.

Topics: Adult; Aortic Valve Insufficiency; Echocardiography; Erythrocytes; Female; Heart Ventricles; Humans; Isometric Contraction; Male; Middle Aged; Muscle Contraction; Radiography; Radionuclide Angiography; Sodium Pertechnetate Tc 99m; Technetium; Technetium Tc 99m Aggregated Albumin

We have evaluated left ventricular regurgitation by means of factor analysis of 99mTc first-pass radionuclide angiography (FPRNA) and time-activity curve deconvolution. The FPRNA regurgitant fraction (RF) was computed in 26 individuals: 13 patients (eight mitral, three aortic, and two mitral-aortic) and 13 controls. The reference method was contrast ventriculography (CV) performed within 1 hr after FPRNA. In 19 patients, CV was preceded by the determination of cardiac output, using indocyanine green dye (n = 16) or thermodilution technique (n = 3), to determine a catheterization regurgitant fraction (CATH-RF). Lung and left ventricular (LV) time-activity curves were gathered by factor analysis and the FPRNA regurgitant fraction assessed by a lagged normal deconvolution of these curves. In valvular regurgitation, the LV deconvolved curve demonstrates the appearance of a long transit time component that is amenable to quantification. The presence of regurgitation was determined by contrast ventriculography. With a 10% RF as an acceptable upper limit of normal for nonregurgitant patients, FPRNA yielded one false-negative and no false-positive studies (n = 26), while CATH-RF yielded two false-negative and four false-positive determinations (n = 19). The following are results of quantitative determination of RF (mean +/- s.d.): FPRNA 0.39 +/- 0.19 (n = 13 Valvular), 0.01 +/- 0.03 (n = 13 Controls); CATH 0.34 +/- 0.24 (n = 11 Valvular), 0.13 +/- 0.12 (n = eight controls). FPRNA was able to differentiate (p less than 0.001) between control patients (CV grading 0) and mild/moderate regurgitation (CV grading 1+ or 2+) and severe regurgitation (3+ or 4+) (p less than 0.025).

Topics: Adult; Aged; Aortic Valve Insufficiency; Evaluation Studies as Topic; Factor Analysis, Statistical; Female; Humans; Male; Middle Aged; Mitral Valve Insufficiency; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

Pulsations of the ascending aorta during fluoroscopy in patients with aortic insufficiency (AI) have been described. The authors present their observations of a similar phenomenon in patients who have AI undergoing scintiangiography. In addition, this paper describes a technique to validate and quantitate this finding. They studied 17 patients with documented AI and 14 subjects of a control group. First-pass studies were acquired in the RAO 15 degrees projection. Regions of interest were placed over the proximal aorta during systole and diastole. An aortic ejection fraction (AF) was determined. The calculated AEF data were correlated with the presence or absence of AI. The mean AEF from the 17 AI patients was 27.1 +/- 7.2%, while the mean for the non-AI group was 12.0 +/- 6.5% with p less than .001. An AEF of 18% separates the two groups with a sensitivity, specificity, and accuracy of 88%, 86%, and 87% respectively. Preliminary data demonstrate a mean reduction in AEF of 12.2 percentage points in 7 AI patients who underwent aortic valve replacement. The AEF may be a useful new parameter to evaluate hemodynamic changes associated with aortic valve replacement in patients with aortic insufficiency.

Topics: Adult; Aorta; Aortic Valve; Aortic Valve Insufficiency; Evaluation Studies as Topic; Female; Heart Valve Prosthesis; Hemodynamics; Humans; Male; Middle Aged; Pulsatile Flow; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

The influence of left ventricular volume variations and regurgitant fraction variations upon left ventricular ejection fraction during exercise was examined using equilibrium radionuclide angiography in patients suffering from aortic regurgitation. Ejection fraction (EF), regurgitant fraction (RF), end diastolic volume (EDV) and end systolic volume (ESV) variations from rest to peak exercise were determined in 44 patients suffering from chronic aortic regurgitation (AR) and in 8 healthy volunteers (C). In C, EF increased (+0.10 +/- 0.03, P less than 0.01) and ESV decreased significantly (-23% +/- 12%, P less than 0.01), RF and EDV did not vary significantly. In AR patients, EF, EDV and ESV did not vary significantly because of important scattering of individual values. Changes in EF and ESV were inversely correlated (r = -0.79, P less than 0.01) and RF decreased significantly (-0.12 +/- 0.10, P less than 0.01). Volumes and EF changes during exercise occurred in three different ways. In a 1st subgroup of 7 patients, EF increased (+0.09 +/- 0.03, P less than 0.05) in conjunction with a reduction of ESV (-24% +/- 12%, P less than 0.05) without a significant change in EDV. In a 2nd group of 22 patients, EF decreased (-0.04 +/- 0.07, P less than 0.01) in association with an increase in ESV (+17% +/- 16%, P less than 0.01) and no change in EDV. In a 2nd group of 22 patients, EF decreased (-0.04 +/- 0.07, P less than 0.01) in association with an increase in ESV (+17% +/- 16%, P less than 0.01) and no change in EDV. In a 3rd subgroup of 15 patients, EF decreased (-0.02 +/- 0.06, P less than 0.01) despite a reduction in ESV (-7% +/- 6%, P less than 0.01) because of a dramatic EDV decrease (-10% +/- 6%, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aortic Valve Insufficiency; Erythrocytes; Exercise Test; Female; Humans; Male; Myocardial Contraction; Physical Exertion; Radionuclide Angiography; Sodium Pertechnetate Tc 99m; Stroke Volume

Topics: Aortic Valve Insufficiency; Erythrocytes; Humans; Mitral Valve Insufficiency; Sodium Pertechnetate Tc 99m; Stroke Volume; Tomography, Emission-Computed

Twenty-three patients with chronic aortic incompetence (17 men and 6 women) aged 27 to 71 years (average 51 years) underwent sequential gamma-angiography at rest and during the different levels of exercise and recovery phase to investigate the evolution of ventricular function and regurgitant fraction and so, guide therapy. The radionuclide indices of left ventricular function (end diastolic and end systolic indexed volumes, global ejection fraction, regional wall motion) and the regurgitant fractions were calculated and compared with clinical, echocardiographic, angiographic and haemodynamic data. The changes observed on effort during gamma-angiography allowed identification of 3 groups of patients: Group I: compensated aortic incompetence with a normal left ventricular ejection fraction (0.69 +/- 0.1), a moderate regurgitant fraction (40 per cent +/- 20 per cent) and, during exercise, a stable left ventricular end diastolic volume index (less than 5 per cent variation), an end systolic volume index which decreased (average-13 per cent), an ejection fraction which increases (by more than 0.05 in 62.5 per cent of cases) and with good global and regional wall motion. Group II: intermediate cases with a left ventricular ejection fraction of 0.62 +/- 0.09 and a regurgitant fraction of 60 +/- 16 per cent. Individual variations were observed with this group which either resembled those of Group I or those of Group III.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Aortic Valve Insufficiency; Chronic Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Contraction; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume

This is an account of 2 groups of 10 patients each who received Starr Edwards ball valves in either the mitral (M) or aortic (A) position on average 14.7 +/- 3 or 14.9 +/- 2.4 years ago, respectively. Non-invasive scintigraphic studies were performed using the first pass of 18 to 20 mCi 99 m-Technetium Pertechnetate. Enddiastolic and endsystolic volumes were found elevated at rest: (M) EDV 135 +/- 50 ml, ESV 63 +/- 30 ml; (A) EDV 163 +/- 41 ml, ESV 69 +/- 25 ml. The response to maximum exercise--during which the heart rate increased from 85 +/- 23 min-1 to 133 +/- 33 min-1--was abnormal, since none of the volumes changed significantly. During exercise, therefore, the increase of the cardiac output was totally heart rate dependent: (M) 6.1 +/- 2.3 to 9.3 +/- 2.3 l/min; (A) 7.0 +/- 1.9 to 10.9 +/- 3.1 l/min. The dynamics of the rapid diastolic filling rate of the left ventricle (RFR) and the mean pulmonary transit time (MTT) served as functional parameters of the Starr Edwards ball valves in the mitral position. The rapid filling rate increased from 205 +/- 98 to 321 +/- 58 ml/sec, whereas MTT decreased from 7.4 +/- 1.4 to 5.4 +/- 2.1 sec. In patients with aortic valve replacement the left ventricular ejection rate was assessed, it rose from 233 +/- 80 to 459 +/- 232 ml/sec. The significant changes of the parameters proved that the Starr Edwards ball valve mechanism functions satisfactorily 11 to 19 years post-operatively.

Topics: Aortic Valve Insufficiency; Aortic Valve Stenosis; Cardiac Output; Exercise Test; Follow-Up Studies; Heart Failure; Heart Valve Prosthesis; Hemodynamics; Humans; Mitral Valve Insufficiency; Mitral Valve Stenosis; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

We studied the exercise ejection fraction response in 56 patients with chronic aortic insufficiency. All had left ventricular dilatation but preserved resting ejection fraction and minimal or no symptoms. The exercise ejection fraction increased by 0.05 units or greater in 18 (32%) patients (group I), remained within 0.05 units of the resting value in 18 (32%) patients (group II), and fell by 0.05 units or greater in 20 (36%) patients (group III). There were no significant differences among the groups in left ventricular end-diastolic dimension, end-systolic dimension, or fractional shortening by echocardiography or in resting left ventricular volumes and ejection fraction by radionuclide angiography. Left ventricular end-systolic wall stress was significantly higher in group III than in either group I or group II (89 +/- 20 vs 70 +/- 18 and 69 +/- 17 X 10(3) dyne/cm2; p less than .005). At peak exercise there were no differences among groups in systolic blood pressure. However, end-systolic volume increased from 65 +/- 28 to 77 +/- 36 ml/m2 in group III and fell from 50 +/- 21 to 28 +/- 18 ml/m2 in group I during exercise. Thus, at peak exercise end-systolic volume was nearly three times greater in group III than in group I. Although stress could not be determined directly during exercise, the directional changes in its determinants suggest that it also would have been higher in group III patients. A highly significant inverse correlation was present between the ejection fraction response and the change in end-systolic volume (r = -.87, p less than .0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Aortic Valve Insufficiency; Blood Pressure; Cardiac Output; Cardiac Volume; Chronic Disease; Echocardiography; Erythrocytes; Exercise Test; Female; Heart; Humans; Male; Middle Aged; Myocardial Contraction; Physical Exertion; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stress, Mechanical; Stroke Volume

Forty consecutive asymptomatic patients with chronic aortic regurgitation who underwent three serial yearly rest and postexercise radionuclide angiograms were compared with 27 consecutive patients with chronic aortic regurgitation and aortic valve replacement who were studied preoperatively, 3 and 15 months postoperatively. Patients were divided into four subgroups based upon the resting left ventricular ejection fraction and the functional reserve on the initial study. Of the 40 medically treated patients, 19 (47.5%) and 24 (60%) demonstrated a response at least one type lower at 12 months and 24 months, respectively. Initial functional reserve, initial duration of exercise, and the change in exercise duration during the 24 months was not associated with changes in resting or postexercise left ventricular ejection fraction. A seesaw pattern was observed between the resting and the postexercise left ventricular ejection fraction as ventricular function deteriorated. We observed in the surgical groups a reversal of the seesaw interaction between the resting and postexercise ejection fraction seen in the medical patients. In the surgical groups the left ventricular end-diastolic pressure, initial functional reserve, initial duration of exercise, and change in exercise duration postoperatively were not predictors of improvement in left ventricular function at 15 months. Comparing medical and surgical serial data, we suggest yearly radionuclide angiographic determination of rest left ventricular ejection fraction in asymptomatic patients with chronic aortic regurgitation. When the rest ejection fraction is less than 50%, exercise angiography should be performed to determine functional reserve. When functional reserve is also abnormal, surgery should be recommended.

Topics: Adolescent; Adult; Aged; Aortic Valve Insufficiency; Cardiac Output; Child; Chronic Disease; Coronary Circulation; Female; Heart Rate; Heart Valve Prosthesis; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Contraction; Physical Exertion; Postoperative Complications; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

To evaluate the usefulness of two-dimensional echocardiography in asymptomatic or minimally symptomatic patients with significant aortic regurgitation and left ventricular enlargement, left ventricular size and function measurements obtained by a nongeometric technique, gated blood pool radionuclide angiography, were compared with measurements made by several two-dimensional echocardiographic methods in 20 patients. Left ventricular size was best assessed by an apical biplane modified Simpson's rule algorithm obtained by computer-assisted planimetry. For end-diastolic volume, r = 0.95 and standard error of the estimate = 25 ml; for end-systolic volume, r = 0.94 and standard error of the estimate = 16 ml. A newly introduced simplified two-dimensional method obviating the need for planimetry and using multiple axis measurements yielded satisfactory results, although volumes larger than 300 ml were markedly underestimated. Evaluation of volumes from a single minor axis measured directly from two-dimensional images and M-mode tracings obtained under two-dimensional echocardiographic control was inadequate for clinical use. Ejection fraction was correctly assessed by the modified Simpson's rule method as well as by the simplified two-dimensional method (r = 0.81 to 0.83, standard error of the estimate = 7%). However, when methods without planimetry were further simplified, a satisfactory correlation was no longer obtained. The M-mode approach using a corrected cube formula also provided an accurate estimation of ejection fraction, a finding that is attributed to the absence of regional wall motion abnormalities in this group of patients, the ability to locate the M-mode beam more adequately under two-dimensional control and the persistence of an ellipsoidal configuration and a circular cross section in the left ventricular chamber. The data indicate that two-dimensional echocardiography is a valuable approach to the assessment of left ventricular size and function in these patients. Moreover, this approach provides a practical and convenient way of improving M-mode evaluation of function and of determining left ventricular shape, thus permitting adequate selection of geometric algorithms for volume calculations.

Topics: Adult; Aged; Aortic Valve Insufficiency; Cardiomegaly; Computers; Echocardiography; Heart; Humans; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume

The change in cardiac output during upright exercise in patients with aortic regurgitation (AR) is not well known. We measured left ventricular (LV) ejection fraction (EF) and volume, regurgitant fraction (RF), total cardiac output and forward cardiac output at rest, and peak upright exercise by means of radionuclide angiography in ten normal subjects and 15 patients with AR. In the normal subjects, there was no significant change in the end-diastolic volume but there was a significant decrease in the end-systolic volume (p = 0.0001) and a significant increase in EF (p = 0.0001). The increase in cardiac output during exercise was due to increases in both stroke volume and heart rate. In patients with AR, there was a significant decrease during exercise in RF (53 +/- 15% at rest, and 45 +/- 15% during exercise; p = 0.03), and in end-diastolic and end-systolic volume (p = 0.02, and p = 0.003, respectively). The EF increased during exercise (p = 0.003). The total stroke volume did not change (68 +/- 19 ml/m2 at rest, and 67 +/- 14 ml/m2 during exercise; p, NS). Thus, in patients with AR, individual changes in EF, RF, and volume are quite variable, but as a group a decrease in RF and an increase in heart rate contribute to the increase in forward flow. The total stroke volume may not increase during exercise, despite an increase in EF and a decrease in end-systolic volume because of a concomitant decrease in end-diastolic volume.

Topics: Adolescent; Adult; Aged; Aortic Valve Insufficiency; Cardiac Output; Female; Heart; Heart Function Tests; Humans; Male; Middle Aged; Physical Exertion; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume

The ability to quantitate aortic (AR) or mitral regurgitation (MR), or both, by radionuclide angiocardiography was evaluated in children and young adults at rest and during isometric exercise. Regurgitation was estimated by determining the ratio of left ventricular stroke volume to right ventricular stroke volume obtained during equilibrium ventriculography. The radionuclide measurement was compared with results of cineangiography, with good correlation between both studies in 47 of 48 patients. Radionuclide stroke volume ratio was used to classify severity: the group with equivocal regurgitation differed from the group with mild regurgitation (p less than 0.02); patients with mild regurgitation differed from those with moderate regurgitation (p less than 0.001); and those with moderate regurgitation differed from those with severe regurgitation (p less than 0.01). The stroke volume ratio was responsive to isometric exercise, remaining constant or increasing in 16 of 18 patients. After surgery to correct regurgitation, the stroke volume ratio significantly decreased from preoperative measurements in all 7 patients evaluated. Results from the present study demonstrate that a stroke volume ratio greater than 2.0 is compatible with moderately severe regurgitation and that a ratio greater than 3.0 suggests the presence of severe regurgitation. Thus, radionuclide angiocardiography should be useful for noninvasive quantitation of AR or MR, or both, helping define the course of young patients with left-side valvular regurgitation.

Topics: Adolescent; Adult; Aortic Valve Insufficiency; Child; Child, Preschool; Erythrocytes; Heart; Humans; Infant; Isometric Contraction; Mitral Valve Insufficiency; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium

Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease.

Topics: Aortic Valve; Aortic Valve Insufficiency; Aortic Valve Stenosis; Arrhythmias, Cardiac; Coronary Angiography; Electrocardiography; Female; Heart; Heart Valve Prosthesis; Heart Ventricles; Hemodynamics; Humans; Male; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium

The stroke-volume ratio determined from the equilibrium gated blood-pool study has been utilized to assess valvular regurgitation, but it is difficult to get reproducible results using generally available equipment. We have developed a new approach utilizing the Fourier amplitude ratio of the left and right ventricles, which is easily implemented and reproducible. Initial clinical experience shows that 17 patients with valvular regurgitation were clearly distinguished from 30 patients without valve disease.

Topics: Aortic Valve Insufficiency; Heart Valve Diseases; Heart Ventricles; Humans; Mitral Valve Insufficiency; Pulmonary Valve Insufficiency; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium; Technology, Radiologic

Exercise radionuclide angiography is being used to evaluate left ventricular function in patients with aortic regurgitation. Ejection fraction is the most common variable analyzed. To better understand the rest and exercise ejection fraction in this setting, 20 patients with asymptomatic or minimally symptomatic severe aortic regurgitation were studied. All underwent simultaneous supine exercise radionuclide angiography and pulmonary gas exchange measurement and underwent rest and exercise measurement of pulmonary artery wedge pressure (PAWP) during cardiac catheterization. Eight patients had a peak exercise PAWP less than 15 mm Hg (group 1) and 12 had a peak exercise PAWP greater than or equal to 15 mm Hg (group 2). Group 1 patients were younger and more were in New York Heart Association class I. Group 1 patients also had a higher mean rest ejection fraction (0.64 +/- 0.08 vs 0.49 +/- 0.13, p less than 0.01, higher exercise ejection fraction (0.63 +/- 0.10 vs 0.40 +/- 0.18, p less than 0.01), lower end-systolic volume (38 +/- 13 vs 79 +/- 36 ml/m2, p less than 0.01) and higher peak oxygen uptake (24.9 +/- 5.1 vs 16.6 +/- 4.9 ml/kg/min, p less than 0.01) than group 2 patients. However, the two groups had similar cardiothoracic ratios, changes in ejection fractions with exercise, and rest and exercise regurgitant indexes. Using multiple regression analysis, the best correlate of the exercise PAWP was peak oxygen uptake (r = -0.78, p less than 0.01). No other measurement added significantly to the regression. When peak oxygen uptake was excluded, rest and exercise ejection fraction also correlated significantly (r = -0.62 and r = -0.60, respectively, p less than 0.01). Patients with asymptomatic or minimally symptomatic severe aortic regurgitation have a wide spectrum of cardiac performance in terms of the PAWP during exercise. The absolute rest and exercise ejection fraction and the level of exercise achieved are noninvasive variables that correlate with exercise PAWP in aortic regurgitation, but the change in ejection fraction with exercise by itself is not.

Topics: Adolescent; Adult; Age Factors; Aged; Aortic Valve Insufficiency; Cardiac Catheterization; Cardiac Output; Exercise Test; Female; Heart Rate; Heart Ventricles; Humans; Male; Middle Aged; Oxygen Consumption; Pressure; Pulmonary Gas Exchange; Pulmonary Wedge Pressure; Radionuclide Imaging; Regression Analysis; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium

Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (greater than or equal to 7.0 minutes) had a significantly higher ejection fraction at rest (probability [p] = 0.02) and during exercise (p = 0.0002), higher cardiac index at exercise (p = 0.0008) and lower exercise end-systolic volume (p = 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both p = 0.001) and cardiac index at rest (p = 0.03) and exercise (p = 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean +/- standard deviation 476 +/- 146 versus 377 +/- 92 mm Hg, p less than 0.05). Thus, in patients with chronic aortic regurgitation: 1) left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and 2) the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest.

Topics: Adolescent; Adult; Age Factors; Aged; Aortic Valve Insufficiency; Cardiac Volume; Echocardiography; Exercise Test; Female; Heart; Heart Ventricles; Humans; Male; Middle Aged; Physical Exertion; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium

First pass radionuclide angiocardiography was utilized to calculate right and left ventricular ejection fraction in 74 infants and children. For the synchronization of radionuclide imaging with the cardiac cycle, the peaks and valleys of corrected ventricular time activity curve were adopted as the time reference points instead of R wave of electrocardiogram. Left ventricular ejection fractions obtained by the radionuclide technique correlated well with those derived from the contrast angiographic technique (r = 0.90), but right ventricular ejection fractions correlated less well (r = 0.74). This noninvasive technique appeared useful for evaluation of right and left ventricular ejection fraction.

Topics: Aortic Valve Insufficiency; Aortic Valve Stenosis; Cardiac Output; Cardiomyopathies; Child; Child, Preschool; Female; Heart Defects, Congenital; Heart Diseases; Humans; Infant; Male; Mitral Valve Insufficiency; Mucocutaneous Lymph Node Syndrome; Pulmonary Valve Insufficiency; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Syndrome; Technetium

This study was performed to assess the effect of pacing-induced tachycardia in patients with aortic regurgitation. In 12 patients (5 men and 7 women with a mean age of 53 years) with aortic regurgitation, left ventricular end-diastolic and end-systolic volume indexes were measured with multigated equilibrium blood pool imaging, and forward cardiac index was determined with thermodilution, both at rest (mean heart rate +/- standard deviation 72 +/- 8 beats/min) and during atrial pacing at 100 and 120 beats/min. Pacing caused a decremental reduction in left ventricular end-diastolic and end-systolic volume indexes and radionuclide-determined stroke volume index but no change in radionuclide-determined cardiac index or left ventricular ejection fraction. Forward cardiac index increased incrementally from the baseline value at rest to that at 120 beats/min despite a decremental reduction in stroke volume index. There was a stepwise decrease in regurgitant volume/stroke (46 +/- 20 ml/m2 at baseline, 27 +/- 15 at 120 beats/min; p less than 0.05) but no change in regurgitant volume/min (3.38 +/- 1.80 liters/min per m2 at baseline, 3.22 +/- 1.78 at 120 beats/min; difference not significant [NS]) or regurgitant fraction (0.54 +/- 0.13 at baseline, 0.49 +/- 0.13 at 120 beats/min; NS). Mean femoral arterial, pulmonary arterial and pulmonary capillary wedge pressures did not change with pacing.

Topics: Aortic Valve Insufficiency; Blood Pressure; Cardiac Catheterization; Cardiac Output; Cardiac Pacing, Artificial; Erythrocytes; Female; Heart; Heart Rate; Humans; Male; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium; Thermodilution

We examined the accuracy with which left ventricular output can be estimated by equilibrium radionuclide ventriculography. After red blood cells were labeled in vivo, we measured left ventricular end-diastolic and end-systolic count rates and the count rate in 5 ml of the patient's blood. After estimating the average ratio of counting efficiency for the left ventricle to counting efficiency for the blood sample (Elv/Es) in six patients, we calculated left ventricular output in 26 other patients as (left ventricular activity ejected per minute divided by activity per liter of blood) divided by the previously estimated Elv/Es. Radionuclide left ventricular output closely approximated Fick cardiac output (r = 0.94) in patients without mitral or aortic regurgitation and exceeded Fick cardiac output in all patients with valvular regurgitation. Regurgitant fraction, calculated as the difference between the radionuclide and Fick outputs divided by the radionuclide output, correlated with the severity of of regurgitation as assessed angiographically. The equilibrium radionuclide ventriculogram is an excellent means for noninvasive estimation of left ventricular output.

Topics: Adult; Aged; Aortic Valve Insufficiency; Blood Volume; Cardiac Catheterization; Cardiac Output; Diastole; Erythrocytes; Female; Heart Ventricles; Humans; Male; Middle Aged; Polyphosphates; Radiography; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Systole; Technetium; Tin Polyphosphates

Quantitative radionuclide angiography (with the first pass technique and a computerized multicrystal camera) was used to evaluate hemodynamic changes in three subject groups during symptom-limited upright exercise. The 12 normal subjects had significant increases in heart rate, stroke volume, left ventricular ejection fraction and cardiac output during exercise; changes in end-diastolic and end-systolic volumes were not significant. In the 24 patients with coronary artery disease there were significant increases in heart rate and cardiac output during exercise, but insignificant changes in end-diastolic, end-systolic and stroke volumes and ejection fraction. The change in diastolic volume in these patients was determined by the extent of coronary artery disease, propranolol therapy, end point of exercise and presence of collateral vessels. Furthermore, patients with previous myocardial infarction had a lower ejection fraction and higher end-diastolic and end-systolic volumes during exercise than those without myocardial infarction. In the 12 patients with chronic aortic regurgitation of moderate to severe degree, there was a decrease in the end-diastolic volume during exercise. This response was distinctly different from that of the normal subjects or the patients with coronary artery disease. All three groups had a significant decrease in pulmonary transit time during exercise. It is concluded that changes in cardiac output in normal subjects during upright exercise are related to augmentation of stroke volume and tachycardia, whereas in patients with coronary artery disease they are related mainly to tachycardia. Left ventricular dilatation during exercise occurred in some normal subjects and in patients with coronary artery disease but was not a consistent finding. However, a decrease in left ventricular end-diastolic volume is common in patients with aortic regurgitation. Such a decrease may be explained by a reduction in the regurgitant volume per beat caused by shortening of the diastolic filling period or a decrease in systemic vascular resistance, or both.

Topics: Adult; Aged; Aortic Valve Insufficiency; Coronary Disease; Electrocardiography; Exercise Test; Female; Heart; Hemodynamics; Humans; Male; Middle Aged; Physical Exertion; Posture; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium

Topics: Aged; Aortic Valve Insufficiency; Blood Vessels; Computers; Electrocardiography; Female; Heart; Humans; Methods; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium; Ventricular Function