Effect of volume load of the left ventricle in aortic and mitral insufficiency on the geometry and function of the right ventricle

To investigate the effect of chronic left ventricular enlargement on right ventricular geometry and function, biplane cineventriculograms were analyzed in 23 patients with aortic regurgitation (AR) and in 17 patients with mitral regurgitation (MR). Left ventricular end-diastolic volume indices (LVEDVI) were elevated and significantly (p less than 0.05) different in patients with aortic regurgitation (AR) (190.2 +/- 65.2 ml/m2) and mitral regurgitation (MR) (148.7 +/- 40.1 ml/m2). Right ventricular end-diastolic volume indices (RVEDVI), however, were comparable and within the normal range (AR: 96.6 +/- 18.3 ml/m2, MR: 100.2 +/- 33.7 ml/m2). Mean pulmonary artery pressure was significantly (p less than 0.05) higher in patients with mitral regurgitation with 24.7 +/- 12.8 mm Hg (AR: 17.5 +/- 6.6 mm Hg). Six patients with mitral insufficiency had concomitant tricuspid valve insufficiency. In five out of six patients with tricuspid insufficiency, right ventricular afterload was significantly elevated. Only in patients with mitral regurgitation was a significant correlation (r) between left and right ventricular end-diastolic volume index found (RVEDVI = 0.7 X LVEDVI +1, r = 0.80). Moreover, in patients with MR, left ventricular end-diastolic volume index correlated with right ventricular end-systolic volume index (RVESVI = 0.4 X LVEDVI -8, r = 0.73). Right ventricular ejection fraction was significantly different (p less than 0.05) between patients with aortic and mitral insufficiency (AR: 53.7 +/- 8.9%, MR: 46.7 +/- 10.7%). Particularly in patients with normal left ventricular ejection fraction (greater than 50%) and mitral regurgitation, the incidence of a reduced right ventricular ejection fraction (less than 50%) was significantly higher (p less than 0.01) compared to patients with aortic regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Improvement in forward cardiac output without a change in ejection fraction during nitroglycerin therapy in patients with functional mitral regurgitation

Left ventricular volumes and forward aortic flow were measured using combined two-dimensional echocardiography and doppler cardiography in seven patients with decompensated congestive heart failure and functional mitral regurgitation prior to and during intravenous administration of nitroglycerin. Total stroke volume was calculated from the difference between end-diastolic and end-systolic volumes, and regurgitant mitral volume from the difference between total stroke volume and forward aortic flow. Regurgitant mitral volume fell from 19 +/- 9 to 3 +/- 3 mL/beat (p less than 0.001), while forward stroke volume increased from 35 +/- 8 to 45 +/- 9 mL/beat (p less than 0.001). The changes were well correlated (r = 0.8, p less than 0.001). Total stroke volume decreased from 54 +/- 12 to 48 +/- 6 mL/beat (p less than 0.05), and ventricular end-diastolic volume from 173 +/- 66 to 158 +/- 66 mL (p less than 0.05). Left ventricular ejection fraction did not change significantly: 33 +/- 9% vs 32 +/- 9% (NS). Thus, in patients with severe congestive heart failure and functional mitral regurgitation, intravenous nitroglycerin redistributes blood flow within the heart by decreasing mitral regurgitation and increasing forward aortic flow, without affecting left ventricular ejection fraction.     

Follow-up studies in chronic aortic insufficiency

In order to study the course of chronic aortic regurgitation 17 patients with various degrees of aortic valve incompetence were investigated twice with a time interval of 1.5 +/- 0.4 years. The following parameters were evaluated: NYHA class; electrocardiographic sum of the largest R-wave in V4-V6 plus the largest S-wave in V1-V3 (RS index); echocardiographic left ventricular end-diastolic diameter (EDD); roentgenographic heart volume (HV); scintigraphic left ventricular end-diastolic volume (EDV), regurgitated blood volume (RBV) and ejection fraction (EF). During the period of observation functional deterioration occurred in 5 cases, all suffering from moderate to severe aortic regurgitation. While EF did not change significantly (55 +/- 12% vs. 55 +/- 11%), all other parameters showed a significant increase: RS index 5.4 +/- 1.4 mVolt to 6.0 +/- 1.7 mVolt (p less than 0.01); EDD 6.3 +/- 0.7 to 6.8 +/- 0.9 cm (p less than 0.001); HV 1017 +/- 151 ml to 1099 +/- 261 ml (p less than 0.01); EDV 371 +/- 131 ml to 441 +/- 175 ml (p less than 0.001); RBV 117 +/- 57 ml to 151 +/- 77 ml (p less than 0.001). Cases with functional deterioration showed a higher initial EDV and EDD (487 +/- 143 vs. 322 +/- 93 ml, p less than 0.05; 7.1 +/- 0.7 vs. 6.1 +/- 0.5 cm, p less than 0.01). The increase of HV, EDV and RBV during the time of observation was higher than in the remaining patients (166 +/- 137 vs. 39 +/- 95 ml, p less than 0.05; 133 +/- 75 vs. 44 +/- 29 ml, p less than 0.01; 66 +/- 22 vs. 22 +/- 31 ml, p less than 0.01). On average it was less pronounced in cases with mild initial left ventricular dilation than in those with marked dilation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Limitations of scintigraphically determined left-ventricular/right-ventricular stroke volume in the evaluation of the severity of aortic valve insufficiency

Noninvasive evaluation of aortic regurgitation can be performed by the radionuclide determination of the left/right ventricular stroke volume ratio. This ratio proved to have a relatively low sensitivity. Therefore, we conducted a study comprising 25 patients with angiographically verified aortic regurgitation in order to look for characteristics of patients with false-negative results. In 5 patients with aortic regurgitation the scintigraphically determined left/right ventricular stroke volume ratio was within normal range. In 3 other patients with severe regurgitation the radionuclide ratio was distinctly lower when compared with the angiographic stroke volume ratio (calculated from the left ventricular stroke volume and effective stroke volume). Left heart failure was observed in all these 8 patients, 7 of 8 patients showed additional right heart failure. Only 2 of the other 17 patients had signs of left heart failure. In the 8 patients with discrepant results, the roentgenographically determined heart volume was increased (1617 vs 1057 ml; 2p less than 0.001), left ventricular ejection fraction decreased (31 vs 60%; 2p less than 0.001), and mean pulmonary artery and right atrial pressure were elevated (38 vs 18 mm Hg; 2p less than 0.001; 11 vs 6 mm Hg; 2p less than 0.001). We conclude that in patients with aortic regurgitation, congestive heart failure associated with functional pulmonic and tricuspid regurgitation and geometric reasons can lead to a reduced sensitivity of the radionuclide left/right ventricular stroke volume ratio.     

Left ventricular function in chronic aortic regurgitation

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.     

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.     

Early postoperative changes in left ventricular chamber size, architecture, and function in aortic stenosis and aortic regurgitation and their relation to intraoperative changes in afterload: a prospective two-dimensional echocardiographic study

We prospectively studied 16 patients with isolated aortic stenosis and eight with isolated aortic regurgitation undergoing aortic valve replacement, using two-dimensional echocardiography preoperatively, intraoperatively, and 41 +/- 7 days postoperatively to calculate the intraoperative change in afterload, quantify the postoperative changes in left ventricular chamber size, architecture, load and function, determine whether the postoperative left ventricular remodeling correlated with the intraoperative change in afterload in aortic stenosis and aortic regurgitation, and assess whether preoperative afterload excess precluded postoperative improvement in left ventricular function. Preoperative left ventricular mass, end-systolic meridional and circumferential wall stresses, ejection fraction, and stress-shortening relations in patients with aortic stenosis and aortic regurgitation were similar. However, our patients with aortic regurgitation had severe systolic dysfunction, with ejection fraction less than 55% in all but one patient, compared with only 10 of 16 patients with aortic stenosis. Left ventricular end-diastolic volume, mass/volume ratio, and chamber shape were significantly different in patients with aortic stenosis and aortic regurgitation (174 +/- 64 vs 294 +/- 140 ml, p less than .01; 1.81 +/- 0.63 vs 1.14 +/- 0.18, p less than .01; and 0.59 +/- 0.09 vs 0.69 +/- 0.09, p less than .05, respectively). Intraoperative end-systolic meridional and circumferential stresses fell significantly in patients with aortic stenosis but remained unchanged in those with aortic regurgitation. The changes in left ventricular volume and ejection fraction during early postoperative remodeling (6 weeks) correlated with the intraoperative change in afterload in patients with aortic stenosis. In contrast, there was no intraoperative change in afterload in patients with aortic regurgitation and no significant changes in left ventricular volume, architecture, or function at 6 weeks or at 6 months. The differences in left ventricular remodeling and changes in function between patients with aortic stenosis and aortic regurgitation in the early postoperative period most probably relates to the major difference in intraoperative reduction in afterload, although a contributory role may have been played by the preoperative left ventricular dysfunction in those with aortic regurgitation that was underestimated by measurement of ejection fraction.     

Reversal of left ventricular dilatation, hypertrophy, and dysfunction by valve replacement in aortic regurgitation

Although aortic valve replacement for aortic regurgitation relieves left ventricular volume overload, ventricular geometry does not consistently normalize. To assess the extent, determinants, and functional consequences of reversal of left ventricular dilatation and hypertrophy, 38 patients with severe aortic regurgitation were studied pre- and postoperatively by serial echocardiography and radionuclide cineangiography. Left ventricular end-diastolic dimension normalized in 58% of patients by 9 +/- 6 months postoperatively, at which time 50% of patients had normalized mass; cumulative normalization rose to 66% for end-diastolic dimension and 68% for left ventricular mass during further follow-up. All patients who had normalized end-diastolic dimension also had normal postoperative ejection fractions (mean 61 +/- 8%). In contrast, patients in whom the left ventricle remained dilated had a 42% prevalence of subnormal postoperative left ventricular ejection fraction. Preoperative left ventricular end-systolic dimension less than or equal to 55 mm identified 86% of patients in whom end-diastolic dimension normalized, whereas end-systolic dimension exceeded 55 mm in 81% of those with persistent dilatation; other proposed preoperative predictors of operative outcome correctly identified lower proportions (from 59% to 71%) of patients in whom left ventricular size did or did not normalize. In conclusion, aortic valve replacement resulted in normalized left ventricular chamber size and mass in two thirds of the patients selected for operation by current criteria; favorable geometric outcome is associated with persistence or recovery of normal left ventricular function.     

Left ventricular function in chronic asymptomatic aortic insufficiency. Angioscintographic study

More accurate information is needed on the usefulness of radionuclide angiography performed during exercise for the assessment of left ventricular function in chronic aortic regurgitation and on its value compared with echocardiography. Between January, 1985 and January, 1988, we studied 23 asymptomatic patients presenting with severe, isolated and pure aortic regurgitation. Nine patients who were not operated upon during that period (group N) had the following characteristics: age 39.4 +/- 12.3 years, left ventricular end-diastolic diameter 67.3 +/- 4.7 mm, left ventricular end-systolic diameter 43.4 +/- 3.2 mm, left ventricular fibre shortening fraction 0.36 +/- 0.05, left ventricular radionuclide ejection fraction 0.67 +/- 0.10 at rest and 0.66 +/- 0.09 during maximum exercise. Compared with the values obtained in 8 controls of the same age (ejection fraction 0.65 +/- 0.07, p less than 0.05, at rest and 0.76 +/- 0.09, p less than 0.05, during maximum exercise), the behaviour of group N patients during exercise was perturbed. Fourteen patients who underwent surgery presented with the following characteristics: age 53.3 +/- 13.3 years (p less than 0.05), left ventricular end-diastolic diameter 71.4 +/- 8.7 mm (p less than 0.05), left ventricular end-systolic diameter 49.4 +/- 6.5 mm (p less than 0.05), fibre shortening fraction 0.31 +/- 0.03 (p less than 0.01), ejection fraction 0.53 +/- 0.08 at rest (p less than 0.001) and 0.40 +/- 0.08 during maximum exercise (p less than 0.001). These results suggest that radionuclide angiography performed during exercise is effective in the early detection and accurate evaluation of myocardial dysfunction in patients with chronic aortic regurgitation at the asymptomatic stage.(ABSTRACT TRUNCATED AT 250 WORDS)     

Size dependence of the end-systolic stress/volume ratio in humans: implications for the evaluation of myocardial contractile performance in pressure and volume overload

The end-systolic stress/volume ratio is currently recognized as a relatively load-independent index of myocardial contractile performance, but its dependence on ventricular size may limit its value for interpatient comparisons. In this study, the relation between the end-systolic stress/volume ratio and left ventricular end-diastolic volume was angiographically analyzed in 104 patients with normal coronary angiograms. Eighteen patients had a normal ventricle, 24 had aortic stenosis, 18 had aortic regurgitation, 9 had mitral regurgitation and 35 had cardiomyopathy. An inverse relation between the end-systolic stress/volume ratio and left ventricular end-diastolic volume was demonstrated in the normal group (r = 0.72, p less than 0.001); subjects with a larger left ventricle had a reduced index but, presumably, the same degree of contractility as that of subjects with a smaller ventricle. Attempts to normalize values by using end-diastolic volume or body surface area were unsuccessful. A similar inverse relation was demonstrated in the aortic stenosis group (r = 0.48, p less than 0.05), probably because hypertrophy helps to keep wall stress normal or low despite progressive ventricular enlargement in these patients. The end-systolic stress/volume ratio was also inversely related to left ventricular chamber size in patients with volume overload due to aortic regurgitation (r = 0.80, p less than 0.001) and in those with cardiomyopathy (r = 0.84, p less than 0.001). However, at a given left ventricular end-diastolic volume, the end-systolic stress/volume ratio was higher in patients with aortic regurgitation than in those with cardiomyopathy, suggesting better contractile performance for a comparable degree of ventricular dilation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Left ventricular volume characteristics and its relationship with right ventricle after repair of tetralogy of Fallot

In order to study the left ventricular volume characteristics and right ventricular influence on left ventricle, cardiac catheterization and biplane cineangiography was performed in 61 patients after repair of tetralogy of Fallot. Preoperative left ventricular volume size was also measured in 25 patients. Postoperative left ventricular end-diastolic volume index (LVEDVI) was 93 +/- 22 ml/m2 (mean +/- standard deviation) and it was 140 +/- 29% of normal left ventricular volume. Left ventricular ejection fraction (LVEF) was 60 +/- 6%. Left ventricular size significantly increased from 109 +/- 25% to 140 +/- 23% of normal by corrective surgery (p less than 0.001). Left ventricular volume characteristics are correlated with right ventricle. LVEDVI increased with increasing right ventricular end-diastolic volume index (RVEDVI) and decreased right ventricular ejection fraction (RVEF). LVEDVI (ml/m2) = 60 + 0.29 RVEDVI (ml/m2), r = 0.52, p less than 0.001, LVEDVI (ml/m2) = 141 - 0.90 RVEF (%), r = -0.30, p less than 0.02. LVEF decreased with increasing RVEDVI and decreased RVEF. LVEF (%) = 68 - 0.075 RVEDVI (ml/m2), r = -0.51, p less than 0.001, LVEF (%) = 43 + 0.32 RVEF (%), r = 0.40, p less than 0.001. On the contrary there was no relationship between right ventricular volume characteristics and right ventricular systolic pressure. There were two cases whose LVEF was less than 50%. In one case right ventricular systolic pressure was as high as 98 mmHg. In the other patient RVEDVI was 299 ml/m2 (453% of normal right ventricular volume) because of severe pulmonary regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Preoperative left ventricular function: minimal requirement for successful late results of valve replacement for aortic regurgitation

Postoperative survival and left ventricular function were studied in 62 patients who underwent aortic valve replacement for isolated, chronic aortic regurgitation between 1978 and 1985. The average follow-up period was 3.8 years. There were three in-hospital and six late deaths. Five (56%) of the nine postoperative deaths were of cardiac-related causes. The mean 7 year survival rate was 83 +/- 5%. Preoperative left ventricular end-systolic volume index was the most important indicator (p less than 0.001) for subsequent cardiac death. The 6.5 year survival rate was 92 +/- 4% for patients with an end-systolic volume index less than 200 ml/m2 compared with 51 +/- 16% for those whose index was greater than 200 ml/m2. None of the 48 patients with an end-systolic volume index less than 200 ml/m2 died of cardiac-related causes. Twenty-three of the 48 patients with an end-systolic volume index less than 200 ml/m2 (Group 1) and 6 of the 12 patients with a higher index (Group 2) underwent repeat catheterization 26 months postoperatively. Preoperative afterload, assessed by end-systolic wall stress, was elevated in both groups, but decreased postoperatively, becoming identical to the afterload in 20 normal control subjects. Although the preoperative ejection fraction was depressed in both groups, the great majority of patients in Group 1, compared with none in Group 2, exhibited normal ejection fraction postoperatively. Thus, in patients who recently underwent surgery for aortic regurgitation, satisfactory late results in both long-term survival and reversal of left ventricular dysfunction were obtained when the preoperative end-systolic volume index was less than 200 ml/m2.     

Long-term nifedipine unloading therapy in asymptomatic patients with chronic severe aortic regurgitation

Vasodilating agents acutely reduce regurgitant volume and improve left ventricular performance in aortic regurgitation, but more information is necessary about their long-term efficacy. To evaluate the effects of 12 months of therapy with nifedipine, a randomized, double-blind, placebo-controlled trial was performed in 72 asymptomatic patients with severe aortic regurgitation. At 12 months, patients receiving nifedipine had a significant reduction in left ventricular end-diastolic volume index (110 +/- 19 versus 136 +/- 22 ml/m2, p less than 0.01) and mass (115 +/- 19 versus 142 +/- 16 g/m2, p less than 0.01) measured by two-dimensional echocardiography. They also had a reduction in left ventricular mean wall stress (360 +/- 27 versus 479 +/- 36 kdyne/cm2, p less than 0.001) and an increase in ejection fraction (72 +/- 8% versus 60 +/- 6%, p less than 0.05). These data show that the long-term unloading action of nifedipine is able to reverse left ventricular dilation and hypertrophy and suggest that such therapy has the potential to delay the need for valve replacement in asymptomatic patients.     

Persisting volume overload of the left ventricle following surgical correction of chronic aortic insufficiency

After aortic valve replacement for chronic aortic regurgitation, complete normalization of the left ventricular end-diastolic volume can rarely be observed. We therefore investigated the role of continual volume overload caused by persisting concomitant mitral regurgitation. 20 patients who received an aortic valve for chronic aortic regurgitation (group 1), 5 patients after operation for aortic stenosis (group 2) and 6 patients with double valve replacement because of aortic and mitral valve lesions were included in the study 1 to 108 months after operation. All patients were examined clinically and by combined first pass/equilibrium radionuclide ventriculography. In the case of significant regurgitation (greater than 20%) 2-dimensional colour-coded Doppler-echocardiography was performed in patients of group 1 to localize the regurgitant lesion. 15 patients of group 1 had a typical systolic murmur indicating mitral regurgitation. 14 of these patients had significant scintigraphic left-sided heart regurgitation: 7 patients had regurgitant fractions between 21 and 40%; 6 patients between 41 and 60%; in 1 patient RF was 64%. Echocardiography confirmed mitral regurgitation in 9 of 11 of these cases. No significant regurgitation was observed in patients of group 2; mild regurgitation was measured in 5 of 6 patients of group 3 (26 to 31%). We conclude that in patients with chronic aortic regurgitation complete normalization of the left ventricular end-diastolic volume after valve replacement may not occur in some patients because of persisting mitral regurgitation.     

Left heart volume characteristics following ventricular septal defect closure in infancy.

Left ventricular and left atrial volume, left ventricular ejection fraction, and left ventricular muscle mass were determined preoperatively and postoperatively in 13 patients who underwent surgical closure of ventricular septal defects in the first two years of life. Left ventricular end-diastolic volume and systolic output averaged 255 +/- 19% (+/- SEM) and 240 +/- 19% of normal, respectively, before operation but fell to within normal limits postoperatively. Left ventricular ejection fraction was normal preoperatively (100 +/- 4% of normal) and remained so after correction (106 +/- 3%, NS). Left ventricular mass was mildly elevated at the preoperative catheterization (271 +/- 21%) and decreased significantly following repair (P less than 0.001). However, the postoperative left atrial volume (147 +/- 14%) remained abnormal (P greater than 0.05). These data suggest that when early surgical closure of a ventricular septal defect is necessary because of failure of medical management, good results with regard to postoperative left ventricular size and function can be expected.     

Mechanics of postextrasystolic potentiation in normal subjects and patients with valvular heart disease

To determine the relative influence of preload, afterload, and inotropic state on postextrasystolic potentiation (PESP) of ventricular performance in man, we computed angiographic left ventricular volume and wall stress frame by frame for a control and potentiated beat in each of 31 patients. In 10 normal subjects, PESP increased ejection fraction by 14%, while left ventricular end-diastolic volume increased by 8% (p less than .001) and end-systolic stress fell by 21% (p less than .005). Enhanced diastolic filling (+6%, p less than .005) with a small decline in end-systolic stress (-8%, p = NS) likewise contributed to potentiation of ejection fraction (+14%, p less than .001) in seven patients with aortic stenosis. Diastolic filling was not significantly augmented during the compensatory pause in six patients with isolated mitral regurgitation, nor in eight patients with aortic regurgitation (+2%, p = NS for both). Although afterload tended to fall for potentiated beats in patients with aortic (-11%, p = NS) and mitral regurgitation (-23%, p = NS), analysis of ejection fraction-end-systolic stress relationships demonstrated an independent effect of inotropic state on potentiated ejection performance. Thus, utilization of preload reserve contributed to PESP in normal subjects and patients with aortic stenosis, but not in those with volume overload imposed by chronic valvular regurgitation. Enhanced inotropic state independent of small changes in afterload was demonstrated in all subgroups.     

Mechanisms for left ventricular systolic dysfunction in aortic regurgitation: importance for predicting the functional response to aortic valve replacement

To test the hypothesis that the combined use of the time-varying elastance concept and conventional circumferential stress-shortening relations would elucidate differential mechanisms for left ventricular systolic dysfunction in severe, chronic aortic regurgitation and therefore predict the functional responses to aortic valve replacement, 31 control patients and 37 patients with aortic regurgitation were studied. The studies included micromanometer left ventricular pressure determinations, biplane contrast cineangiograms under control conditions and radionuclide angiograms under control conditions and during methoxamine or nitroprusside infusions with right atrial pacing. The patients with aortic regurgitation were classified into three groups: Group I had normal Emax and stress-shortening relations, Group II had abnormal Emax but normal stress-shortening relations and Group III had abnormal Emax and stress-shortening relations. The left ventricular end-diastolic and end-systolic volumes showed a progressive increase and the ejection fraction showed a progressive decrease from Group I to III; these values differed from those in the control patients (p less than 0.001). In Group I, there was a decrease in left ventricular volumes (p less than 0.05) but no significant change in ejection fraction (61 +/- 7% versus 63 +/- 4%) after aortic valve replacement. In contrast, in Group II, reduction in left ventricular volumes (p less than 0.01) was associated with an increase in ejection fraction from 50 +/- 8% to 64 +/- 11% (p less than 0.01). Finally, in Group III, reduction in left ventricular volumes (p less than 0.05) was associated with a further decrement in ejection fraction from 35 +/- 13% to 30 +/- 13%. Group I patients had compensated adequately for chronic volume overload. However, Group II had left ventricular dysfunction that was associated with an increase in the left ventricular volume/mass ratio compared with that in the control patients and Group I (p less than 0.05 for both), suggesting inadequate hypertrophy and assumption of spherical geometry. Finally, irreversible myocardial dysfunction had supervened in Group III. In conclusion, a combined analysis of left ventricular chamber performance using the time-varying elastance concept and myocardial performance using conventional circumferential stress-shortening relations provides complementary information that elucidates differential mechanisms for left ventricular systolic dysfunction and therefore predicts the functional response to aortic valve replacement.     

Late results of prosthetic valve replacement for aortic regurgitation and the prognostic significance of the end-diastolic and regurgitated blood volumes

Between January 1975 and December 1985 214 patients underwent prosthetic aortic valve replacement for isolated aortic regurgitation. Patient follow-up averaged 5.4 years after the operation (range 0.7-10.7 years). Preoperative staging showed 9 patients to be in NYHA stage II, 111 patients in stage III, and 94 patients in stage IV. At follow-up 3 patients complained of increased fatigue, 9 patients remained stable and 167 patients had improved. 103 of these patients were free of symptoms under stress, i.e. NYHA stage I. The hospital mortality was 3.7% (8/214 patients). An additional 26 patients died within an average of 2.8 years. The cumulative 5-year survival rate was 85%; the 10-year survival rate was 81.5%. 10 patients underwent a second operation within an average of 3.4 years. The correlation between the end-diastolic volume and the regurgitated blood volume has prognostic significance. 25 patients with appropriate enlargement of the left ventricle showed a significant decrease of the end-diastolic volume and the roentgenographic heart volume combined with an increase of ejection fraction. None of these 25 patients died from cardiac complications. A control group of 9 patients with myocardial damage showed no significant change in the above parameters. 4 patients in the control group died. We conclude that the relationship of regurgitated blood volume and the left ventricular end-diastolic volume is of prognostic significance for patients with chronic aortic regurgitation presenting with minimal symptoms.     

Relationship of contractile state to ejection performance in patients with chronic aortic valve disease

To assess the relative contributions of afterload mismatch and impaired contractility to pump dysfunction in patients with chronic aortic valve disease, simultaneous left ventricular cineangiography and micromanometry were performed in 56 patients: 21 with severe aortic stenosis, 16 with severe aortic regurgitation, and 19 normal control subjects. Left ventricular mass was increased in patients with aortic stenosis and aortic regurgitation (172 +/- 52 and 224 +/- 63 g/m2, respectively, vs 89 +/- 16 for control subjects; p less than .05) as were end-diastolic volume (101 +/- 39 and 167 +/- 44 vs 77 +/- 16 ml/m2; p less than .05) and end-systolic volume (50 +/- 40 and 84 +/- 43 vs 24 +/- 7 ml/m2; p less than .05). Although ejection fraction was depressed in both abnormal groups (0.56 +/- 0.18 for patients with aortic stenosis and 0.53 +/- 0.13 for those with aortic regurgitation vs 0.69 +/- 0.05 for control subjects; p less than .05), the decrease in ejection fraction was disproportionate to the mild degree of afterload mismatch (end ejection stress 129 +/- 17 in patients with aortic stenosis and 154 +/- 58 in those with aortic regurgitation vs 117 +/- 46 kdyn/cm2 in control subjects; p = NS) with 10 of 21 patients with aortic stenosis and 12 of 16 patients with aortic regurgitation falling below the 95% prediction limit of the linear inverse relationship between ejection fraction and end-systolic stress for controls (EF = 0.78 - 0.00074 X ESS).(ABSTRACT TRUNCATED AT 250 WORDS)     

Anatomo-functional correlations of changes in electrocardiographic repolarization in aortic and mitral valve insufficiency. Comparison of indices based on QRS voltages

Electrocardiographic repolarization changes and voltage criteria for left ventricular hypertrophy were examined, in relation to hemodynamic, echocardiographic and angiographic data. This was done to evaluate their association with abnormalities in cardiac function and structure in 53 patients with chronic aortic regurgitation and 36 patients with chronic mitral regurgitation. No patient showed evidence of coronary artery disease. Of the patients with aortic regurgitation, the 27 patients with an abnormal repolarization pattern at ECG had worse NYHA functional class when compared to the 24 patients with normal repolarization (2.4 +/- 1 vs 1.6 +/- 0.9; p less than .01). They also had greater left ventricular dimensions (end-diastolic volume: 162 +/- 57 ml/m2 vs 109 +/- 15 ml/m2, p less than .01; end-systolic volume: 85 +/- 46 ml/m2 vs 44 +/- 31 ml/m2, p less than .01), lower left ventricular ejection fraction (.50 +/- .12 vs .63 +/- .14; p less than .01), greater left ventricular mass (170 +/- 56 gr/m2 vs 119 +/- 29 gr/m2; p less than .01) and higher end-diastolic left ventricular pressure (21 +/- 11 mmHg vs 11 +/- 8 mmHg; p less than .01). QRS voltage was less closely related to cardiac function and structure and thus, did not modify the conclusions based on repolarization findings alone. Furthermore, repolarization patterns identified patient subgroups with high or low prevalences of previously described predictors of poor surgical outcome. The presence or absence of the "strain" pattern was not related to differences in cardiac structure and function, in patients with mitral regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)