Study of the value of corrected ejection fraction in the evaluation of left ventricular function in patients with mitral or aortic regurgitation

Evaluation of left ventricular function in the presence of valvular regurgitation is still a clinical problem because ejection phase indices including ejection fraction are heavily dependent on preload and afterload and cannot be regarded as reliable indices of contractility in diseases associated with altered loading conditions. The authors attempted to evaluate the usefulness of the new index-corrected ejection fraction in the evaluation of left ventricular (LV) function in patients with chronic mitral (MR) or aortic regurgitation (AR). The study included 21 patients with chronic severe MR (11 patients) and AR (10 patients) with a mean age of 18 years. All patients underwent valve replacement or repair. Echo Doppler study was performed preoperatively and postoperatively and included measurement of the following LV parameters: end-diastolic dimension (EDD), end-diastolic volume (EDV), end-systolic dimension (ESD), end-systolic volume (ESV), ejection fraction (EF), systolic blood pressure/end-systolic dimension (SBP/ESD); also mitral and aortic stroke volume were calculated cross-sectional area (CSA) x time velocity integral TVI. Corrected ejection fraction (EFc) was derived from the following equation: EFc = [EF + square root of (ASV x MSV) / EDV] / 2. The mean preoperative EFc did not change significantly after surgical correction of mitral or aortic regurgitation. Preoperative EFc did not show significant difference compared with postoperative EF in the two groups. Preoperative EFc correlated significantly with other preoperative and postoperative indices of LV function. Postoperative EFc showed very close correlation with other postoperative parameters. Thus, using the new index-corrected ejection fraction in the assessment of LV function in patients with mitral or aortic regurgitation has several advantages: Noninvasive, independent of loading changes, helpful in predicting the immediate postoperative clinical course, and a reliable index for evaluation of LV systolic function preoperatively and postoperatively.     

Volumetric evaluation of aortic regurgitation by combined first-pass/equilibrium radionuclide ventriculography

In 16 men with normal valvular function (group 1) and 23 men and one woman with isolated aortic regurgitation (group 2) effective stroke was determined by first-pass radionuclide ventriculography. Total left ventricular stroke volume was derived from equilibrium radionuclide ventriculography using a geometric approach for the end-diastolic volume multiplied by the ejection fraction. The difference between the two stroke volumes as a fraction of total left ventricular stroke volume was taken as radionuclide regurgitant fraction. Radionuclide lv/rv stroke count ratio was calculated as the ratio of end-diastolic-end-systolic count-rate differences from the left and right ventricles. All patients underwent left heart catheterization. Angiographic regurgitant fraction was evaluated by the method of Sandler and Dodge in 16 patients of group 2. In the others, aortic regurgitation was quantified in 5 grades of severity. Group l was classified correctly by both radionuclide regurgitant fraction and lv/rv stroke count ratio (specificity 100%). In group 2 the radionuclide regurgitant fraction was elevated in all (from + 20% to +88%, sensitivity 100%), radionuclide lv/rv stroke count ratio in 19 of 24 cases (from 0.6 to 5.6, sensitivity 79%). The angiographic regurgitant fraction correlated well with the radionuclide regurgitant fraction (r = 0.78), whereas no significant correlation was found between the angiographic stroke volume ratio (i.e. left ventricular stroke volume/cardiac output per beat) and radionuclide stroke count ratio (r = 0.10) due to the high rate of false-negative results of the latter method.(ABSTRACT TRUNCATED AT 250 WORDS)     

Relationship between echocardiography, cardiac output, and abnormally contracting segments in patients with ischemic heart disease.

Twenty-four patients with proven coronary artery disease and abnormally-contracting segments were studied by both echocardiography and biplane angiographic techniques. Comparison was made between the left ventricular biplane angiographic volumes and those obtained from echocardiographic measurements which were calculated from cubed function and regression equaltion methods. The percent abnormally contracting segment (ACS) was obtained from biplane left ventricular angiography and was calculated from the diastolic and systolic anteroposterior and lateral angiocardiograms. The angiographic end-diastolic volume correlated with that calculated from the echocardiographic dimensions with an r value of 0.865 and SEE of +/- 22.64 ml. The angiographic end-systolic volume and echo end-systolic volume did not correlate as well, with an r = 0.7063. The difference in stroke volume predicted by the diastolic and systolic echocardiographic dimensions and the actual stroke volume determined by Fick technique was related to the percent abnormally contracting segment of the left ventricle (r = 0.8967). The percent ACS could be estimated from echo and Fick stroke volume measurements by the cube function and regression equations. Echo ventricular volume determinations were analyzed for the cube function method and the regression equations of Fortuin et al. and Teichholz and coworkers, with the method of Fortuin et al. producing the most sensitive relationship: % ACS = 0.32 (SVecho - SVFick) % + 8.9%. The correlation coefficient for the estimate was 0.8967 with a SEE of +/- 4.78%. In patients with coronary artery disease and abnormally contracting segments, echocardiography can provide reliable measurements of left ventricular end-diastolic volume but estimates of end-systolic volume are less accurate. If mitral regurgitation or a ventricular aneurysm can be excluded, the difference in echocardiographic and forward stroke volume by an independent method is related to the angiographic and forward stroke volume by an independent method is related to the angiographic abnormally contracting segment, and this relationship permits estimation of the size of the abnormally, contracting segment.     

Quantitative evaluation of cineaortography in the assessment of aortic regurgitation

Cineaortography, quantitative biplane left ventricular angiocardiography and Fick cardiac output studies were performed in 69 patients with aortic regurgitation to evaluate the usefulness of the aortogram in quantitating regurgitation. Thirteen patients had coexistent aortic stenosis and 12 had coexistent mitral stenosis. Patients with concomitant mitral regurgitation were excluded because their aortic regurgitant flow cannot be separately quantified with biplane ventriculography. Twenty-eight other patients without valvular regurgitation were also studied to assess further the accuracy of the quantitative ventriculography, and the stroke volumes derived from Fick and angiographic methods were found to correlate well (r = 0.97). Aortic regurgitation in the 69 patients, graded on a 1 to 5 scale from the aortogram, correlated significantly with the percent and volume of regurgitation (r = 0.56 and 0.65, P < 0.01), respectively). However, there was a wide range in amount of regurgitant flow within the aortographic grades, especially in grades 4 and 5, and there was considerable overlap between the grades. The degree of aortic regurgitation was more commonly overestimated than underestimated from the aortogram, but the correlation tended to be better in the patients with a large end-diastolic volume and normal ejection fraction and without aortic or mitral stenosis.     

End-systolic volume as a predictor of postoperative left ventricular performance in volume overload from valvular regurgitation

Although over-all cardiac performance may remain normal in patients with left ventricular volume overload from valvular regurgitation, impairment of myocardial function may occur and remain undetected by currently accepted methods of assessing ventricular performance. Since end-systolic volume reflects myocardial contractile function yet is independent of preload, we assessed preoperative end-systolic volume as a measure of myocardial function in 41 patients with aortic regurgitation, mitral regurgitation or both. Preoperative end-systolic volume was compared to postoperative left ventricular performance as measured by postoperative echocardiographic per cent dimension change (% ΔD) and New York Heart Association class. Preoperative end-systolic volume correlated well with postoperative left ventricular performance in patients with aortic regurgitation (r = 0.77) or mitral regurgitation (r = 0.73). Much poorer correlations existed for preoperative ejection fraction, enddiastolic volume or left ventricular end-diastolic pressure. Preoperative end-systolic volume also predicted patients at high risk for perioperative cardiac death, with all such cardiac deaths occurring in patients with an end-systolic volume >60 cc/m². Again, both preoperative ejection fraction and end-diastolic volume were less precise predictors of surgical outcome. Patients with aortic regurgitation appeared to tolerate a larger end-systolic volume better than those with mitral regurgitation.End-systolic volume is an easily determinable parameter of left ventricular function which is independent of the abnormal preload that occurs in mitral regurgitation and aortic regurgitation and appears to provide a measure for the onset of myocardial dysfunction in patients with these lesions. Whether this myocardial dysfunction is due to a depressed inotropic state of individual sarcomeres, a stress-shortening imbalance or to other factors is unknown, but its presence has major prognostic importance.     

Left ventricular volume determined echocardiographically by assuming a constant left ventricular epicardial long-axis/short-axis dimension ratio throughout the cardiac cycle.

OBJECTIVES. The purpose of this study was to develop and test a simplified echocardiographic method to calculate left ventricular volume. BACKGROUND. This method was based on the assumption that the ratio of the left ventricular epicardial long-axis dimension to the epicardial short-axis dimension was constant throughout the cardiac cycle. With use of this constant ratio, the method developed to calculate left ventricular volume at a given point in the cardiac cycle required the left ventricular endocardial long-axis dimension to be measured at only one point in the cardiac cycle. METHODS. Studies were performed in 13 normal dogs, 8 normal puppies, 9 normal pigs, 12 dogs with aortic stenosis, 13 dogs with acute mitral regurgitation, 12 dogs with chronic mitral regurgitation, 7 dogs that had undergone mitral valve replacement and 6 pigs that had had chronic supraventricular tachycardia. Animals with aortic stenosis developed left ventricular pressure overload hypertrophy with a 60% increase in left ventricular mass; chronic mitral regurgitation caused left ventricular volume overload hypertrophy with a 46% increase in left ventricular volume; supraventricular tachycardia caused a dilated cardiomyopathy with a 55% decrease in left ventricular ejection fraction. RESULTS. The left ventricular epicardial long-axis/short-axis dimension ratio remained constant throughout the cardiac cycle in each animal group. End-diastolic and end-systolic volumes calculated with the simplified echocardiographic method correlated closely with angiographically measured volumes; for end-diastolic volume, echocardiographic end-diastolic volume = 1.0 (angiographic end-diastolic volume) -1.8 ml, r = 0.96; for end-systolic volume, echocardiographic end-systolic volume = 0.98 (angiographic end-systolic volume) -0.7 ml, r = 0.95. CONCLUSIONS. Thus the left ventricular epicardial long-axis/short-axis dimension ratio was constant throughout the cardiac cycle in a variety of animal species and age groups and in the presence of cardiac diseases that significantly altered left ventricular geometry and function. The simplified echocardiographic method examined provided an accurate determination of left ventricular volumes.     

Noninvasive quantification of mitral regurgitation in dilated cardiomyopathy: correlation of two Doppler echocardiographic methods

The presence and severity of functional mitral regurgitation were quantified by Doppler echocardiography in 17 patients with dilated cardiomyopathy and no evidence of primary valvular disease. Mitral regurgitant fraction was greater than 20% in 11 of the 17 patients, and exceeded 40% in four patients. Total stroke volume, calculated from the difference between end-diastolic and end-systolic volumes obtained by two-dimensional echocardiography, correlated well with mitral valve inflow determined by Doppler echocardiography (r = 0.90, p less than 0.001). Similarly, mitral regurgitant volume, calculated as the difference between echocardiographic total stroke volume and forward aortic volume obtained by Doppler echocardiography, correlated well with regurgitant volume calculated as the difference between mitral valve inflow and forward aortic flow, both determined by Doppler echocardiography (r = 0.90, p less than 0.001). Accordingly, functional mitral regurgitation can be conveniently demonstrated in patients with dilated cardiomyopathy by two different Doppler echocardiography methods, whose results are closely correlated. Mitral regurgitant fraction is greater than 20% in two thirds of the patients with a dilated cardiomyopathy.     

Doppler-derived rate of left ventricular pressure rise. Its correlation with the postoperative left ventricular function in mitral regurgitation

A new Doppler-derived index of the rate of left ventricular (LV) pressure rise (delta P/delta t) was evaluated for the prognostic stratification of patients with chronic mitral regurgitation. The index is derived from the continuous wave Doppler mitral regurgitation signal by dividing magnitude of LV-left atrial pressure gradient rise (delta p) between 1 and 3 m/sec of the mitral regurgitation velocity signal by the time taken (delta t) for this change. We studied the LV delta P/delta t and other echocardiographic indexes of LV function before and after mitral valve surgery in 25 patients with chronic, severe mitral regurgitation in the absence of significant coronary artery disease. There was a good correlation between postoperative ejection fraction (EF) and the derived LV delta P/delta t (r = 0.75, p less than 0.001). The other echocardiographic parameters that correlated with postoperative EF were LV end-systolic dimension (r = -0.7, p less than 0.001), end-systolic volume (r = -0.69, p less than 0.001), end-diastolic dimension (r = -0.58, p less than 0.01), end-diastolic volume (r = -0.57, p less than 0.01), preoperative EF (r = 0.69, p less than 0.001), end-systolic wall stress (r = -0.61, p less than 0.01), and end-systolic wall stress normalized for end-systolic volume index (r = -0.45, p less than 0.05). With multiple regression, the LV delta P/delta t and LV end-systolic dimension (ESD) were shown to be independent predictors of postoperative EF. The postoperative EF could defined by the equation: 43 + 0.8 square root delta P/delta t--0.53 ESD (mm) (r = 0.86).(ABSTRACT TRUNCATED AT 250 WORDS)     

Early changes in left ventricular size and function after correction of left ventricular volume overload

The ability to predict early postoperative left ventricular size and function in patients with isolated aortic or mitral regurgitation was determined utilizing multigated blood pool imaging before and 2 to 4 weeks after valve replacement (aortic valve, 20 patients; mitral valve, 20 patients). Early postoperatively, ejection fraction decreased significantly (p <0.001) in both patient groups (from 0.55 ± 12 to 0.40 ± 0.14 [mean ± 1 standard deviation] in patients with aortic regurgitation and from 0.66 ± 0.09 to 0.48 ± 0.11 in patients with mitral regurgitation). The decrease in ejection fraction was associated with a large decrease in stroke volume with minimal or no change in end-systolic volume; it was unrelated to the preoperative ejection fraction. Early postoperative ejection fraction correlated best with preoperative end-systolic volume and was normal in 14 (67 percent) of 21 patients with a preoperative ejection fraction above 0.60; 4 (27 percent) of 15 patients with a preoperative ejection fraction of 0.50 to 0.60; and in 0 of 4 patients with a preoperative ejection fraction below 0.50 (p <0.05). In addition, a repeated scan in 16 patients late (1 to 2 years) after operation showed a further reduction in endsystolic volume in patients with aortic regurgitation with an increase in ejection fraction toward preoperative values. There was no significant change in patients with mitral regurgitation.End-diastolic volume decreased significantly (p <0.001) early postoperatively (from 162 ± 60 to 102 ± 41 ml/m² in patients with aortic regurgitation and from 131 ± 40 to 78 ± 30 ml/m² in patients with mitral regurgitation). This decrease was closely related to a decrease in stroke volume and was unrelated to preoperative ejection fraction. Early postoperative end-diastolic volume correlated best with the preoperative end-systolic volume. The major part of the reduction in end-diastolic volume occurred within 2 weeks of valve replacement.Removal of chronic left ventricular volume overload due to aortic or mitral regurgitation produces a decrease in ejection fraction and end-diastolic volume. The early reduction is in part a result of altered loading conditions and may not necessarily imply alterations in myocardial contractile function. The reduction in ejection fraction appears to persist in patients with mitral regurgitation.     

Hemodynamic consequences of afterload reduction in patients with chronic aortic regurgitation.

Nitroprusside was used to reduce afterload in 13 patients with isolated, severe aortic regurgitation. The drug significantly lowered mean aortic pressure, pulse pressure, left ventricular end-diastolic pressure and left ventricular volume. Total ventricular, or angiographic, cardiac index was generally unaffected, but forward cardiac index was improved significantly in 8 of 13 patients. Augmentation of forward cardiac index was seen in patients with subnormal resting forward cardiac index, in patients with decidedly elevated end-diastolic pressure, and in those with depressed resting ejection fractions. Regurgitant fraction fell with nitroprusside in six patients and remained unchanged in seven. Total stroke work index was diminished in all patients. These data show that afterload reduction in patients with severe aortic regurgitation may improve hemodynamics by reducing aortic regurgitation or by improving ventricular pump function. The lowered total stroke work, reduced ventricular size and improved forward cardiac index imply that afterload reduction may benefit left ventricular failure and delay progressive ventricular dysfunction in patients with aortic regurgitation.     

Echocardiographic characteristics in patients > or =100 years of age

The centenarian population is increasing, and patients > or =100 years old are encountered more frequently in clinical practice. Cardiovascular disease is the most common cause of death in this subset of patients. We report the echocardiographic characteristics of 63 hospitalized centenarians. Patients ranged in age from 100 to 112 years and were admitted to the hospital for a variety of diagnoses. The mean left ventricular end-diastolic dimension was 3.9 +/- 0.7 cm (2.8 to 5.8), the mean left ventricular end-systolic dimension was 1.8 +/- 0.7 cm (0.8 to 3.5), the mean ventricular septal thickness was 1.2 +/- 0.25 cm (0.8 to 1.9), the mean left ventricular posterior wall thickness was 1.1 +/- 0.14 cm (0.8 to 1.6), the mean left ventricular ejection fraction was 84% +/- 11% (49% to 97%), the mean aortic root diameter at the level of the sinuses was 3.3 +/- 0.4 cm (2.1 to 4.1), the mean left atrial dimension was 4.5 +/- 0.7 cm (3.1 to 7), the mean right ventricular end-diastolic dimension was 3.4 +/- 0.6 cm (2.0 to 4.8), and the mean pulmonary artery systolic pressure was 37 +/- 14 mm Hg. Moderate or severe valvular lesions were common, including aortic stenosis (27%), aortic regurgitation (17%), mitral regurgitation (22%), and tricuspid regurgitation (28%). In conclusion, centenarian hearts have important differences from younger hearts, including more hypertrophied left ventricle, higher ejection fraction, higher pulmonary artery systolic pressure, and more prevalent significant valvular heart disease.     

Noninvasive evaluation of the magnitude of aortic and mitral regurgitation by means of Doppler two-dimensional echocardiography

Using transmitral flow velocity and left ventricular ejection flow velocity, we measured left ventricular inflow volume (LVIV) and left ventricular outflow volume (LVOV) by pulsed Doppler echocardiography in 73 patients who had mitral valve regurgitation (MR), aortic valve regurgitation (AR), or no valvular regurgitation. Doppler-determined regurgitant volume (DOPRV), Doppler-determined regurgitant fraction (DOPRF), total stoke volume, and forward stroke volume were calculated to compare the severity assessed by angiographic scoring and the regurgitant fraction determined by radionuclide angiography (RIRF). In 17 patients with MR, LVIV (84.4 +/- 20.4 ml) was significantly greater (p less than 0.01) than LVOV (52.5 +/- 15.7 ml). LVOV, which is equivalent to forward stroke volume, was lower in patients with MR (52.2 +/- 15.7 ml) than in normal subjects (67.0 +/- 15.7 ml). In 15 patients with AR, LVOV (121.7 +/- 61.1 ml) was significantly greater (p less than 0.01) than LVIV (75.1 +/- 28.1 ml) and LVOV, which is equivalent to total stroke volume, was greater in patients with AR (121.7 +/- 61.1 ml) than in normal subjects (64.0 +/- 14.4 ml). DOPRF correlated with RIRF (r = 0.79, p less than 0.01, n = 11). DOPRV (mild: 10.5 +/- 8.5 ml; moderate: 28.8 +/- 13.6 ml; severe: 74.5 +/- 36.7 ml) and DOPRF (mild: 13.7% +/- 11.5%; moderate: 33.1% +/- 14.2%; severe: 52.6% +/- 15.3%) increased markedly with the severity of regurgitation as assessed by cineangiography. In AR, total stroke volume influenced both forward stroke volume and regurgitant volume, and in MR, regurgitant volume influenced both total stroke volume and forward stroke volume. Total stroke volume in AR and regurgitant volume in MR may play a key role in valvular regurgitation.     

Limitations of comparing left ventricular volumes by two dimensional echocardiography,myocardial markers and cineangiography

Measurement of left ventricular volume at end-diastole or end-systole with both two dimensional echocardiography and either Cineangiography or radionuclide scans, not recorded simultaneously, has shown large echocardiographic underestimation of volumes even in normal ventricles. In this study fluoroscopic and two dimensional echocardiographic recordings were obtained in 18 patients with abnormal wall motion and previously implanted myocardial markers. The echocardiographic values for volume and those derived from myocardial markers correlated well (r = 0.87), and there were no statistically significant differences in values obtained with the two methods at end-diastole or end-systole. The ejection fractions obtained with two dimensional echocardiography (mean ± standard deviation 46 ± 7 percent) and with fluoroscopic recording of the markers (41 ± 9 npercent) did not differ statistically.These results were compared with those in another 18 patients (nine with abnormal wall motion) having two dimensional echocardiography within 24 hours of a 30 ° right anterior oblique contrast left ventriculogram. Again, two dimensional echocardiographic ventricular volume correlated well with the angiographic volume (r = 0.85), although echocardiographic end-diastolic volume was consistently 20 percent less than angiographic end-diastolic volume (p < 0.01). Ejection fraction obtained with echocardiography (47 ± 8 percent) was less than that obtained with angiography (60 ± 7 percent) (p < 0.001). Interobserver variability in calculating volume with echocardiography was 4 percent.Probable reasons for the lack of severe underestimation of volume with echocardiography even in very abnormal ventricles, relative to that demonstrated in prior reports, include improvements in ultrasonic beam width, tracing method, transducer position and scan plane orientation within the ventricle. In addition, the possible effects of angiographic dye in the ventricular trabeculae are discussed and the effect of simultaneous studies by two different methods are compared.     

Predictors of long-term survival after valve replacement for chronic aortic regurgitation; is M-mode echocardiography sufficient?

AIMS: The clinical importance of pre-operative and follow-up echocardiographic studies in patients operated on for chronic severe aortic valve regurgitation is still a matter of debate. The prognostic significance of M-mode echocardiography has never been directly compared with clinical and angiographic data. METHODS AND RESULTS: Univariate and multivariate analyses of cumulative survival were performed for clinical, echocardiographic and angiographic data of 125 patients operated on between 1975 and 1983, and followed for 13.3+/-6.4 years. Ten and 20 year survival rates were 77% and 48%, respectively. Age, NYHA class, angiographic volumes, ejection fraction, as well as M-mode echocardiographic end-systolic dimension and shortening fraction were the main pre-operative prognostic parameters for long-term survival. In a multivariate analysis the angiographic end-systolic volume index, age and preoperative NYHA class were independent pre-operative prognostic variables of long-term survival. A postoperative reduction in end-diastolic dimension of >20% predicted a significantly better late survival (74% vs 44% after 20 years, P<0.001). CONCLUSIONS: Age, pre-operative NYHA class and left ventricular systolic function are the main determinants of long-term survival after valve replacement for chronic aortic regurgitation. Despite a slightly lower predictive value of echocardiography when compared to angiography, it appeared sufficient for everyday clinical decision making for valve replacement. Echocardiography within 6 months postoperatively is able to detect recovery of left ventricular function, and enables additional risk-stratification, regardless of pre-operative findings.     

Influence of heart rate and atrial transport on left ventricular volume and function: relation to hemodynamic changes produced by supraventricular arrhythmia

The response of the left ventricle to pacing-induced changes in heart rate and the atrioventricular (A-V) relation was examined with equilibrium gated radionuclide ventriculography in 20 patients who had normal ventricular function after surgery for recurrent supraventricular tachycardia. In 10 patients count-derived left ventricular ejection fraction, end-diastolic volume and stroke volume were measured during sinus rhythm and during atrial pacing at 120, 140 and 160 beats/min. In the other 10 patients similar determinations were made during sequential A-V and simultaneous ventricular and atrial (V/A) pacing, both at rates of 100 and 160 beats/min. Left ventricular ejection fraction did not change significantly with atrial pacing (from 0.65 +/- 0.02 [mean +/- standard error of the mean] at a baseline sinus rate of 91 +/- 3 beats/min to 0.62 +/- 0.03 at 160 beats/min) despite a progressive decrease in end-diastolic volume. The percent reduction in end-diastolic volume (% delta EDV) and stroke volume (+ delta SV) from the baseline values was linear and related to change in heart rate (delta HR) as % delta EDV = -0.60 delta HR + 5.19 (r = 0.71; p less than 0.01) and % delta SV = -0.62 delta HR + 5.03 (r = 0.76; p less than 0.001). Left ventricular ejection fraction with baseline sequential A-V pacing at 100 beats/min was 0.67 +/- 0.03 and not significantly altered by either sequential A-V or simultaneous V/A pacing at 160 beats/min. At 100 beats/min, loss of atrial transport with simultaneous V/A pacing resulted in a small reduction in end-diastolic volume from a baseline value of -9.0 +/- 1.9 percent (p less than 0.01) and a nonsignificant reduction in stroke volume of -3.7 +/- 1.6 percent. During simultaneous V/A pacing at 160 beats/min, the reduction in end-diastolic and stroke volumes from the baseline value was -26.6 +/- 3.8 percent and -28.8 +/- 4.3 percent, respectively (both p less than 0.01), but was significantly smaller (-16.1 +/- 3.6 percent and -19.2 +/- 4.1 percent, respectively [p less than 0.05]) when atrial transport was maintained during sequential A-V pacing at the same heart rate. During simultaneous V/A pacing at 160 beats/min, two thirds of the reduction in end-diastolic and stroke volumes from the baseline value was due to the increment in heart rate as assessed from sequential A-V pacing and the other third was due to loss of atrial transport. The data indicate that the hemodynamic consequences of supraventricular tachyarrhythmias in patients with normal ventricular function are due primarily to decreases in ventricular volume as heart rate is increased and atrial contribution is lost rather than to any changes in left ventricular ejection fraction.     

Three echocardiographic methods in right ventricular function evaluation

We employed two-dimensional echocardiography for the assessment of right ventricular (RV) volumes and/or function in a series of 44 patients. The results of three different echocardiographic approaches were compared with the data obtained from single-plane RV angiography following ultrasound within a 7-day interval. Only the echocardiographic area length method with two orthogonal imaging planes employed (apical 4-chamber and subcostal projections) yielded the beneficial results. The correlations between echocardiographic and angiographic RV volume estimates were rather high (end-diastolic volume: r = 0.83, end-systolic volume: r = 0.82, stroke volume: r = 0.81) and satisfactory in ejection fraction (r = 0.75). Using the method mentioned, the differentiation of patients with an angiographic evidence of RV failure (echocardiographic ejection fraction less than 0.55) from those without it was possible with a sensitivity of 0.68 and a specificity of 0.82. Concerning the clinical impact of the presented study, we can recommend the technique in question as a screening procedure for the detection of changes in RV function exceeding 12% (95% confidence limits).     

Is angiographic ventriculography necessary for the assessment of ischemic patients?

A total of 53 patients with a provisional diagnosis of ischemic heart disease and without any clinical evidence of valvular, congenital, or primary muscle heart disease were studied by echocardiography and biplane left ventricular cineangiography. For angiographic ejection fraction analysis, a program developed in our department for use on an Apple Macintosh computer interfaced to a digitizing tablet was employed. Echocardiographic outlines of systolic and diastolic images were traced with a digitizing system on the screen and ejection fractions were calculated by a program incorporated in the echo machine. Good echo windows allowing ejection fraction calculations were present in 35 patients. There was a good correlation between angiographic and echocardiographic ejection fraction (r = 0.7, SEE = 0.09), and wall motion assessment revealed no significant discrepancies between the two image modalities. The remaining 18 patients had poor echo windows, preventing accurate echocardiographic determination of the ejection fraction. However, limited assessment of left ventricular size and wall motion was possible in all patients and allowed the identification of those who had impaired left ventricular function as judged by angiography (angiographic ejection fraction < 35%). We conclude that even in patients with poor echo windows echocardiographic assessment of left ventricular function provides clinical information similar to angiography which should not be considered mandatory for the investigation of ordinary ischemic patients.     

Measurement of aortic regurgitation by Doppler echocardiography.

In an attempt to develop a new approach to the non-invasive measurement of aortic regurgitation, transmitral volumetric flow (MF) and left ventricular total stroke volume (SV) were measured by Doppler and cross sectional echocardiography in 23 patients without aortic valve disease (group A) and in 26 patients with aortic regurgitation (group B). The transmitral volumetric flow was obtained by multiplying the corrected mitral orifice area by the diastolic velocity integral, and the left ventricular total stroke volume was derived by subtracting the left ventricular end systolic volume from the end diastolic volume. The aortic regurgitant fraction (RF) was calculated as: RF = 1 - MF/SV. In group A there was a close agreement between the transmitral volumetric flow and the left ventricular total stroke volume, and the difference between the two measurements did not differ significantly from zero. In group B the left ventricular total stroke volume was significantly larger than the transmitral volumetric flow, and there was good agreement between the regurgitant fractions determined by Doppler echocardiography and radionuclide ventriculography. Discrepancies between the two techniques were found in patients with combined aortic and mitral regurgitation or a low angiographic left ventricular ejection fraction (less than 35%). The effective cardiac output measured by Doppler echocardiography accorded well with that measured by the Fick method. Doppler echocardiography provides a new and promising approach to the non-invasive measurement of aortic regurgitation.     

Measurement of aortic regurgitation by Doppler echocardiography

In an attempt to develop a new approach to the non-invasive measurement of aortic regurgitation, transmitral volumetric flow (MF) and left ventricular total stroke volume (SV) were measured by Doppler and cross sectional echocardiography in 23 patients without aortic valve disease (group A) and in 26 patients with aortic regurgitation (group B). The transmitral volumetric flow was obtained by multiplying the corrected mitral orifice area by the diastolic velocity integral, and the left ventricular total stroke volume was derived by subtracting the left ventricular end systolic volume from the end diastolic volume. The aortic regurgitant fraction (RF) was calculated as: RF = 1 - MF/SV. In group A there was a close agreement between the transmitral volumetric flow and the left ventricular total stroke volume, and the difference between the two measurements did not differ significantly from zero. In group B the left ventricular total stroke volume was significantly larger than the transmitral volumetric flow, and there was good agreement between the regurgitant fractions determined by Doppler echocardiography and radionuclide ventriculography. Discrepancies between the two techniques were found in patients with combined aortic and mitral regurgitation or a low angiographic left ventricular ejection fraction (less than 35%). The effective cardiac output measured by Doppler echocardiography accorded well with that measured by the Fick method. Doppler echocardiography provides a new and promising approach to the non-invasive measurement of aortic regurgitation.     

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.