Mitral regurgitation: a new clinical perspective

Mitral regurgitation is a common valvular heart disease, particularly in the elderly population. The timing of surgical repair is controversial, but recent literature suggests a new clinical perspective on the management of this disease. Despite receiving medical treatment and having few initial symptoms, patients with mitral regurgitation due to flail leaflets have an excess mortality rate (6.3% per year) and high morbidity. Ten years after mitral regurgitation has been diagnosed, 90% of the patients have either died or undergone an operation. After surgical correction of mitral regurgitation, left ventricular dysfunction is a frequent complication and is the cause of excess heart failure and mortality. This complication is due to preoperative left ventricular dysfunction but is incompletely predictable with use of current methods. Conversely, considerable progress in surgery has resulted in an extremely low operative mortality rate (about 1% in patients younger than 75 years of age) and high feasibility of valve repair, even in patients with anterior leaflet prolapse. These facts have led to the new perspective that early surgical correction (before occurrence of overt symptoms or left ventricular dysfunction) should be considered when patients are diagnosed with severe mitral regurgitation.

Determinants of the pulmonary artery pressure rise in left ventricular dysfunction

Pulmonary artery hypertension in patients with left ventricular dysfunction is related to poor outcome but the role of cardiac functional abnormalities in the genesis of pulmonary hypertension remains unknown. The aim of this prospective study was to identify the determinants of pulmonary hypertension in 102 consecutive patients with primary left ventricular dysfunction (ejection fraction < 50%). Systolic pulmonary artery pressure was measured by continuous wave Doppler. Left ventricular systolic and diastolic function, severity of functional mitral regurgitation, cardiac output, and left atrial volume were assessed using Doppler echocardiography. In patients with left ventricular dysfunction, systolic pulmonary artery pressure was increased (51 +/- 14 mmHg, range 23 to 87 mmHg). Mitral deceleration time (r = -0.61; p = 0.0001) and mitral effective regurgitant orifice (r = 0.50; p = 0.0001) were the strongest parameters related to systolic pulmonary artery pressure. Multivariate analysis identified these two variables as the strongest predictors of systolic pulmonary artery pressure in association with the mitral E/A ratio (p = 0.006) and age (p = 0.005). In conclusion, pulmonary hypertension is common and variable in patients with left ventricular dysfunction. It is closely related to diastolic dysfunction and severity of functional mitral regurgitation but not independently to the degree of left ventricular systolic dysfunction. These findings underline the importance of assessing diastolic function and quantifying mitral regurgitation in patients with left ventricular dysfunction.

Early surgery in patients with mitral regurgitation due to flail leaflets: a long-term outcome study

BACKGROUND

The optimal timing for surgery in patients with mitral regurgitation is disputed. Because of the frequency of left ventricular dysfunction, which is difficult to predict, early surgery has been recommended, but its potential benefits have not been demonstrated.

METHODS AND RESULTS

The outcomes of 221 patients (mean age, 65 +/- 13 years; 71% males) with flail leaflets diagnosed with two-dimensional echocardiography between 1980 and 1989 who were eligible for operation were analyzed. Group I comprised 63 patients who had early mitral valve surgery (within 1 month after diagnosis). Group II comprised 158 patients initially treated conservatively (80 of whom were operated on later). Group I patients were younger (P=.009), had more symptoms (P<.0001), and were more frequently in atrial fibrillation (P=.023) than group II patients. There was no difference in ejection fraction between the groups. The early surgery strategy was followed by an improved overall survival rate (P=.028) and a lower incidence of cardiovascular deaths (P=.025), congestive heart failure (P=.046), and new chronic atrial fibrillation (P=.032), as confirmed by multivariate analysis (adjusted risk ratios of 0.31, 0.18, 0.38, and 0.05, respectively; all P<.02).

CONCLUSIONS

In patients with mitral regurgitation due to flail leaflets, the strategy of early surgery versus conservative management is associated with an improved long-term survival rate, decreased cardiac mortality, and decreased morbidity after diagnosis. This outcome advantage suggests that early surgery is a reasonable treatment option to be considered in low-risk candidates with repairable valves and severe mitral regurgitation.

Optimizing timing of surgical correction in patients with severe aortic regurgitation: role of symptoms

OBJECTIVES

We sought to determine the independent effect of preoperative symptoms on survival after surgical correction of aortic regurgitation (AR).

BACKGROUND

Aortic valve replacement for severe AR is recommended after New York Heart Association functional class III or IV symptoms develop. However, whether severe preoperative symptoms have a negative influence on postoperative survival remains controversial.

METHODS

Preoperative characteristics and postoperative survival in 161 patients with functional class I or II symptoms (group 1) were compared with those in 128 patients with class III or IV symptoms (group 2) undergoing surgical repair of severe isolated AR between 1980 and 1989.

RESULTS

Compared with group 1, group 2 patients were older (p < 0.0001), were more often female (p = 0.001) and more often had a history of hypertension (p = 0.001), diabetes mellitus (p = 0.029) or myocardial infarction (p = 0.005) and were more likely to require coronary artery bypass graft surgery (p < 0.0001). The operative mortality rate was higher in group 2 (7.8%) than in group 1 (1.2%, p = 0.005), and the 10-year postoperative survival rate was worse (45% +/- 5% [group 2] vs. 78% +/- 4% [group 1], p < 0.0001). Compared with age- and gender-matched control subjects, long-term postoperative survival was similar to that expected in group 1 (p = 0.14) but significantly worse in group 2 (p < 0.0001). On multivariate analysis, functional class III or IV symptoms were significant independent predictors of operative mortality (adjusted odds ratio 5.5, p = 0.036) and worse long-term postoperative survival (adjusted hazard ratio 1.81, p = 0.0091).

CONCLUSIONS

In the setting of severe AR, preoperative functional class III or IV symptoms are independent risk factors for excess immediate and long-term postoperative mortality. The presence of class II symptoms should be a strong incentive to consider immediate surgical correction of severe AR.

Determination of ventricular ejection fraction: a comparison of available imaging methods. The Cardiovascular Imaging Working Group

Knowledge of left ventricular ejection fraction has been shown to provide diagnostic and prognostic information in patients with known or suspected heart disease. In clinical practice, the ejection fraction can be determined by using one of the five currently available imaging techniques: contrast angiography, echocardiography, radionuclide techniques of blood pool and first pass imaging, electron beam computed tomography, and magnetic resonance imaging. In this review, we discuss the clinical application as well as the advantages and disadvantages of each of these methods as it relates to determination of ventricular ejection fraction.

Papillary fibroelastoma: echocardiographic characteristics for diagnosis and pathologic correlation

OBJECTIVES

We sought to determine the clinical and echocardiographic characteristics of papillary fibroelastoma (PFE).

BACKGROUND

PFE is a rarely encountered cardiac tumor about which relatively little is known.

METHODS

Institutional records were reviewed for the years 1980 to 1995 for patients with pathologic or echocardiographic diagnosis of PFE. Group 1 included 17 patients with the pathologic diagnosis of PFE who also underwent echocardiography. Echocardiographic features of PFE were established in group 1. Group 2 included 37 patients with only echocardiographic evidence of PFE.

RESULTS

In group 1, 7 (41.2%) of 17 patients had symptoms related to PFE. Neurologic events occurred in 5 (29.4%) of 17 patients. All patients had the tumor surgically removed. During follow-up, no new embolic events occurred. Echocardiographic characteristics of PFE included a small tumor (12.1 +/- 6.5 x 9.0 +/- 4.3 mm), usually pedunculated (14 [94%] of 17 patients) and mobile, with a homogeneous speckled pattern and a characteristic stippling along the edges. PFEs were most common on valvular surfaces (12 [60%] of 20 PFEs) but were not uncommon on other endocardial surfaces (8 [40%] of 20 PFEs). The tumor did not cause valvular dysfunction. In group 2, 16 (43%) of 37 patients were asymptomatic. Five patients (13.5%) had a previous neurologic event. During follow-up (mean 31 months, range 1 to 77), nine neurologic events occurred.

CONCLUSIONS

PFEs are associated with embolism, can be diagnosed with echocardiography, are often an incidental clinical finding and do not cause valvular dysfunction.

Eosinophilic myocarditis manifesting as myocardial infarction: early diagnosis and successful treatment

OBJECTIVE

To report a case of eosinophilic myocarditis with remarkable initial clinical manifestations and outcome.

MATERIAL AND METHODS

A 67-year-old woman with hypertension and a history of asthma and drug hypersensitivity was referred to our institution with a diagnosis of acute myocardial infarction on the basis of severe chest pain, ST elevation on an electrocardiogram, and a slight increase in cardiac enzymes. Further diagnostic studies were performed.

RESULTS

Echocardiography disclosed left ventricular dysfunction in conjunction with apical asynergy, thinning, and thrombus. The eosinophil count in the peripheral blood was increased only slightly. Coronary angiography showed normal arteries and prompted the performance of endomyocardial biopsy, which revealed active eosinophilic myocarditis. After corticosteroid therapy, global and regional left ventricular function returned to normal.

CONCLUSION

This unusual clinical picture and outcome demonstrate that eosinophilic myocarditis may simulate acute myocardial infarction and should be considered in patients with a history of allergies or acute left ventricular dysfunction, even in the absence of pronounced eosinophilia in the peripheral blood. With appropriate medical therapy, recovery for these patients can be complete.

Outcome after surgery for mitral regurgitation. Determinants of postoperative morbidity and mortality

BACKGROUND AND AIMS OF THE STUDY

The incidence and impact of congestive heart failure and coronary artery disease on late survival after surgical correction of mitral regurgitation are poorly defined. In addition to the uncertainty about the frequency of this complication, the mechanisms of heart failure have not been fully analyzed.

METHODS

To determine survival and the incidence and mechanisms of congestive heart failure after mitral valve surgery for mitral regurgitation, we analyzed the long-term outcome of 576 consecutive postoperative survivors.

RESULTS

The analysis demonstrated that preserved preoperative left ventricular function (ejection fraction > or = 60%) was associated with improved survival (adjusted risk ratio 0.49; 95% C.I. 0.36-0.661) and reduced incidence of congestive heart failure (adjusted risk ratio 0.30; 95% C.I. 0.20-0.441), while concomitant coronary artery disease was associated with an excess mortality (adjusted risk ratio 1.80; 95% C.I. 1.34-2.41) and incidence of congestive heart failure (adjusted risk ratio 2.12; 95% C.I. 1.48-3.031).

CONCLUSIONS

These results suggest that left ventricular dysfunction and coronary artery disease are major determinants of mortality and morbidity after surgical correction of mitral regurgitation. For the prevention of postoperative congestive heart failure, early surgical correction of mitral regurgitation should be considered before left ventricular dysfunction occurs.

Determinants of pulmonary hypertension in left ventricular dysfunction

OBJECTIVES

This study sought to analyze the determinants of pulmonary hypertension in patients with left ventricular dysfunction.

BACKGROUND

Pulmonary hypertension in patients with left ventricular dysfunction is a predictor of poor outcome. The independent role of cardiac functional abnormalities in the genesis of pulmonary hypertension is unclear.

METHODS

In 102 consecutive patients with primary left ventricular dysfunction (ejection fraction < 50%), systolic pulmonary artery pressure was prospectively measured by Doppler echocardiography (using tricuspid regurgitant velocity), and left ventricular systolic and diastolic function, functional mitral regurgitation, cardiac output and left atrial volume were quantified.

RESULTS

Systolic pulmonary artery pressure was elevated in patients with left ventricular dysfunction (51 +/- 14 mm Hg [mean +/- SD]), but the range was wide (23 to 87 mm Hg). Of the numerous variables correlating significantly with systolic pulmonary artery pressure, the strongest were mitral deceleration time (r = -0.61, p = 0.0001; odds ratio of pulmonary pressure > or = 50 mm Hg [95% confidence interval] if < 150 ms, 48.8 [14.8 to 161]) and mitral effective regurgitant orifice (r = 0.50, p = 0.0001; odds ratio [95% confidence interval] if > or = 20 mm2, 5.9 [2.3 to 15.5]). In multivariate analysis, these two variables were the strongest predictors of systolic pulmonary artery pressure in association with age (p = 0.005). Ejection fraction or end-systolic volume was not an independent predictor of pulmonary artery pressure.

CONCLUSIONS

Pulmonary hypertension is frequent and highly variable in patients with left ventricular dysfunction. It is not independently related to the degree of left ventricular systolic dysfunction but is strongly associated with diastolic dysfunction (shorter mitral deceleration time) and the degree of functional mitral regurgitation (larger effective regurgitant orifice). These results emphasize the importance of assessing diastolic function and quantifying mitral regurgitation in patients with left ventricular dysfunction.

Surgery for aortic regurgitation in women. Contrasting indications and outcomes compared with men

BACKGROUND

Indications for surgical correction of aortic regurgitation have been established mostly in men and have not been validated in women. The outcome of this surgical correction in women is unknown.

METHODS AND RESULTS

Baseline characteristics and postoperative outcomes were compared between 51 women and 198 men undergoing surgery for isolated aortic regurgitation between 1980 and 1989. Compared with men, women had surgery rarely for severe left ventricular enlargement (systolic diameter > or = 55 mm in 11% versus 27%, P = .031; diastolic diameter > or = 80 mm in 0% versus 16%, P < .0001) and more often for class III to IV symptoms (59% versus 32%, P < .0001). Operative mortalities were similar in women and men (3.9% and 4.5%, respectively). Among operative survivors, 10-year survival was worse for women than for men (39 +/- 9% versus 72 +/- 4%, P = .0002) and, in contrast with men, was worse than expected for women (P < .0001). Independent predictors of late survival were different for men (age and ejection fraction) and women (age and concomitant coronary bypass grafting). By multivariate analysis, female sex was an independent predictor of worse late survival (adjusted relative risk, 1.80; 95% CI, 1.04 to 3.11).

CONCLUSIONS

The generalization to women of the unadjusted left ventricular diameter surgical criteria established in men results in irrelevant criteria almost never reached in women, who often undergo surgery after developing severe symptoms. After surgery, women exhibit an excess late mortality, suggesting that surgical correction of aortic regurgitation should be considered at an earlier stage in women.

Clinical outcome of mitral regurgitation due to flail leaflet

BACKGROUND

Mitral regurgitation due to flail leaflet is difficult to manage, because it is frequently asymptomatic yet carries a high risk of left ventricular dysfunction and because the natural history of the condition is poorly defined.

METHODS

We obtained clinical follow-up data through 1994-1995 in 229 patients with isolated mitral regurgitation due to flail leaflet; this condition was first diagnosed by echocardiography between 1980 and 1989.

RESULTS

The 86 patients who were treated medically had a mortality rate significantly higher than expected (6.3 percent yearly, P=0.016 for the comparison with the expected rate in the U.S. population according to the 1990 census). Independent determinants of mortality were an older age, the presence of symptoms, and a lower ejection fraction. Patients who were even transiently in New York Heart Association functional class III or IV had a high mortality rate (34 percent yearly), but the rate was also notable (4.1 percent yearly) among those in class I or II. At 10 years, the mean (+/- SE) rates of heart failure, atrial fibrillation, and death or surgery were 63 +/- 8, 30 +/- 12, and 90 +/- 3 percent, respectively. In a multivariate analysis, surgical correction of mitral regurgitation (performed in 143 patients) was associated with a reduced mortality rate (hazard ratio, 0.29; 95 percent confidence interval, 0.15 to 0.56; P<0.001).

CONCLUSIONS

When treated medically, mitral regurgitation due to flail leaflet is associated with excess mortality and high morbidity. Surgery is almost unavoidable within 10 years after the diagnosis and appears to be associated with an improved prognosis; this finding suggests that surgery should be considered early in the course of the disease.

Secular trends in coronary atherosclerosis--analysis in patients with valvular regurgitation

BACKGROUND

Between 1980 and 1989, mortality due to coronary artery disease decreased considerably in the United States, suggesting a possible decrease in the prevalence of coronary atherosclerosis. We examined this possibility in patients with valvular regurgitation who, often in the absence of angina, underwent coronary angiography before valve-replacement surgery.

METHODS

We studied 601 patients with isolated, nonischemic valvular regurgitation who were operated on between 1980 and 1989 and who had undergone preoperative coronary angiography. From the angiograms we determined the prevalence of clinically significant coronary artery disease and of multivessel disease, assessed the mean degree of stenosis, and analyzed the trends in the data over the years of the study.

RESULTS

The prevalence of coronary artery disease (35 percent in 1980-1981, 37 percent in 1982-1983, 34 percent in 1984-1985, 37 percent in 1986-1987, and 35 percent in 1988-1989; P = 0.97) did not change significantly during the study period. We found no significant change in the prevalence of multivessel disease (24 percent in 1980-1981 and 23 percent in 1988-1989, P = 0.99) or in the mean ( +/- SD) degree of stenosis (11 +/- 13 percent in 1980-1981 and 13 +/- 14 percent in 1988-1989, P = 0.07). When these measures of coronary atherosclerosis were adjusted for age and sex, there were still no significant changes over time (P = 0.39 for the prevalence of coronary artery disease, P = 0.81 for that of multivessel disease, and P = 0.57 for the mean degree of stenosis). The patients' mean total cholesterol level decreased from 219 +/- 48 mg per deciliter (5.66 +/- 1.24 mmol per liter) to 206 +/- 44 mg per deciliter (5.33 +/- 1.14 mmol per liter) between 1980 and 1989 (P = 0.04).

CONCLUSIONS

From 1980 to 1989, no significant change was observed in angiographic measures of coronary atherosclerosis in patients with nonischemic valvular regurgitation, in contrast to the marked decrease in mortality due to coronary disease in the general population. These findings suggest that the well-documented reduction in mortality due to coronary disease may not be due to a reduction in the prevalence of coronary atherosclerosis.

Aortic regurgitation complicated by extreme left ventricular dilation: long-term outcome after surgical correction

OBJECTIVES

This study sought to determine the outcome of aortic valve replacement for aortic regurgitation complicated by extreme left ventricular dilation.

BACKGROUND

Aortic valve replacement has been recommended in aortic regurgitation with extreme left ventricular dilation (diastolic dimension >/= 80 mm), but extreme left ventricular dilation raises concern about irreversible left ventricular dysfunction.

METHODS

Thirty-one patients with a preoperative echocardiographic diastolic dimension >/= 80 mm (group 1) undergoing operation for severe isolated aortic regurgitation between 1980 and 1989 were compared with 188 patients with a diastolic dimension <80 mm operated on during the same period (group 2).

RESULTS

Preoperatively, extreme left ventricular dilation was seen only in male patients and was associated with a reduced ejection fraction (43 +/- 12% vs. 53 +/- 11% [mean +/- SD], p < 0.0001). The postoperative outcome of group 1 was compared with that of male patients in group 2 (group 2M, n = 144). The operative mortality rates for groups 1 and 2M were 0% and 5.6%, respectively (p = 0.35). Late survival in operative survivors was similar in groups 1 and 2M, but compared with expected survival, an excess mortality was observed for group 1 (p = 0.024). Preoperative ejection fraction, but not diastolic dimension, independently predicted late survival and postoperative ejection fraction. Postoperatively, groups 1 and 2M showed a similar improvement in ejection fraction, but persistent left ventricular enlargement was more frequent in group 1.

CONCLUSIONS

Extreme left ventricular dilation due to aortic regurgitation is observed in male patients and is frequently associated preoperatively with a reduced ejection fraction but is not a marker of irreversible left ventricular dysfunction. Operative risk and late postoperative survival are acceptable in these patients, although a late excess mortality, predicted best by preoperative ejection fraction, is observed. Therefore, extreme left ventricular dilation is not a contraindication to operation, which should be performed before left ventricular dysfunction occurs.

Intensity of murmurs correlates with severity of valvular regurgitation

PURPOSE

To evaluate the relationship between the intensity of murmurs and severity of mitral and aortic regurgitation.

PATIENTS AND METHODS

Consecutive patients with chronic isolated aortic (n = 40) or mitral (n = 170) regurgitation undergoing echocardiographic quantitation of regurgitation between 1990 and 1991 were studied. Regurgitant volume and fraction were measured using two simultaneous methods (quantitative Doppler echocardiography and quantitative two-dimensional echocardiography); the intensity of the regurgitant murmur (grade 0 to 6) was noted by physicians unaware of the study.

RESULTS

Correlations between murmur intensity and regurgitant volume and fraction were good in aortic regurgitation (r = .60 and r = .67, respectively; P < 0.001) and mitral regurgitation (r = .64 and r = .67, respectively; P < 0.001) but weaker (r = .47 and r = .45, respectively) in the subset of mitral regurgitation of ischemic or functional cause. Murmur intensity grades > or = 3 for aortic regurgitation and > or = 4 for mitral regurgitation predicted severe regurgitation (regurgitant fraction > or = 40%) in 71% and 91% of patients, respectively. Murmur grades < or = 1 for aortic regurgitation and < or = 2 for mitral regurgitation predicted "not severe" regurgitation in 100% and 88% of patients, respectively. Murmur grades 2 for aortic regurgitation and 3 for mitral regurgitation were not correlated to degree of regurgitation. The severity of regurgitation was the most powerful determinant of intensity of murmur.

CONCLUSIONS

Murmur intensity correlates well with the degree of chronic organic aortic and mitral regurgitation, and can be used as a predictor of regurgitation severity and as a simple guideline for diagnostic testing in these patients.

Changes in effective regurgitant orifice throughout systole in patients with mitral valve prolapse. A clinical study using the proximal isovelocity surface area method

BACKGROUND

In patients with mitral valve prolapse, spontaneous changes of the effective regurgitant orifice during systole are not well documented. Such changes can now be analyzed by use of the proximal isovelocity surface area method, but the changes raise concern about the reliability of this method for assessing overall severity of regurgitation in these patients.

METHODS AND RESULTS

In a prospective study of 42 patients with mitral valve prolapse, the effective mitral regurgitant orifice was calculated at four phases of systole (early, mid, mid-late, and late) as the ratio of regurgitant flow to regurgitant velocity by use of the proximal isovelocity surface area method. Throughout systole, the effective regurgitant orifice increased significantly, from 32 +/- 27 mm2 in early systole to 41 +/- 27 in midsystole, 55 +/- 30 in mid-late systole, and 107 +/- 66 mm2 during late systole (P < .0001). Phasic regurgitant volume increased from early to mid-late systole but decreased in late systole. For quantitation of the overall effective regurgitant orifice, four approaches using the proximal isovelocity surface area were compared with simultaneously performed quantitative Doppler echocardiography (54 +/- 30 mm2) and quantitative two-dimensional echocardiography (51 +/- 29 mm2). All correlations were good (r > .95), but overestimation was considerable when the largest flow convergence was used (70 +/- 39 mm2; both P < .0001), significant when the simple mean of the four phases was used (59 +/- 36 mm2; P = .005 and P = .0007, respectively), mild when a weighted mean of the four phases was used (55 +/- 33 mm2; P = .41 and P = .01, respectively), and no overestimation was observed when the effective regurgitant orifice calculated at maximum regurgitant velocity was used (54 +/- 30 mm2; P = .29 and P = .17, respectively).

CONCLUSIONS

Phasic changes of mitral regurgitation are observed in patients with mitral valve prolapse. The effective regurgitant orifice increases throughout systole. Regurgitant volume also increases initially but tends to decrease in late systole. These changes can lead to overestimation of the overall degree of regurgitation, but properly timed measurements made by use of the proximal isovelocity surface area method allow an accurate estimation of the overall effective regurgitant orifice.

Congestive heart failure after surgical correction of mitral regurgitation. A long-term study

BACKGROUND

In patients with mitral regurgitation, surgical intervention produces immediate improvement in symptoms, but the long-term incidence and significance of postoperative congestive heart failure are unknown.

METHODS AND RESULTS

The long-term outcome of 576 operative survivors of surgical correction of pure mitral regurgitation performed between 1980 and 1989 was analyzed. Survival was 77 +/- 2% and 56 +/- 3% at 5 and 10 years, respectively. Cumulative incidence of congestive heart failure was 23 +/- 2%, 33 +/- 3%, and 37 +/- 3% at 5, 10, and 14 years, respectively. Survival after the first episode of congestive heart failure was dismal, 44 +/- 4% at 5 years. Cause of congestive heart failure was left ventricular dysfunction in two thirds of the patients and valvular dysfunction in the other third. With multivariate analysis, the independent predictors of postoperative heart failure were preoperative ejection fraction (P = .0001), coronary artery disease (P = .0017), and New York Heart Association functional class (P = .012), with borderline value for atrial fibrillation (P = .10). The performance of valve repair was independently predictive of a lower incidence of the combined end point of death and heart failure (P = .001), compared with valve replacement.

CONCLUSIONS

Congestive heart failure frequently occurs late after surgical correction of mitral regurgitation and portends dismal prognosis. This complication is due most often to left ventricular dysfunction; its main determinant is decreased left ventricular function preoperatively. These data should lead to earlier indication of surgical correction of mitral regurgitation, before left ventricular dysfunction occurs.

Effective mitral regurgitant orifice area: clinical use and pitfalls of the proximal isovelocity surface area method

OBJECTIVES

We attempted to determine the accuracy and pitfalls of calculating the mitral regurgitant orifice area with the proximal isovelocity surface area method in a clinical series that included patients with valvular prolapse and eccentric jets.

BACKGROUND

The effective regurgitant orifice area, a measure of lesion severity of mitral regurgitation, can be calculated by the proximal isovelocity surface area method, the accuracy and pitfalls of which have not been established.

METHODS

In 119 consecutive patients with isolated mitral regurgitation, effective regurgitant orifice area was measured by the proximal isovelocity surface area method and compared with measurements simultaneously obtained by quantitative Doppler and quantitative two-dimensional echocardiography.

RESULTS

The effective mitral regurgitant orifice area measured by the proximal isovelocity surface area method tended to be overestimated compared with that measured by quantitative Doppler and quantitative two-dimensional echocardiography (38 +/- 39 vs. 36 +/- 33 mm2 [p = 0.09] and 34 +/- 32 mm2 [p = 0.02], respectively). Overestimation was limited to patients with prolapse (61 +/- 43 vs. 56 +/- 35 mm2 [p = 0.05] and 54 +/- 34 mm2 [p = 0.014]) and was restricted to patients with nonoptimal flow convergence (n = 7; 137 +/- 35 vs. 84 +/- 34 mm2 [p = 0.002] and 79 +/- 33 mm2 [p = 0.002]). In patients with optimal flow convergence (n = 112), excellent correlations with both reference methods were obtained (r = 0.97, SEE 6 mm2 and r = 0.97, SEE 7 mm2, p < 0.0001).

CONCLUSIONS

In calculating the mitral effective regurgitant orifice area with the proximal isovelocity surface area method, the observed pitfall (overestimation due to nonoptimal flow convergence) is rare. Otherwise, the method is reliable and can be used clinically in large numbers of patients.

Valve repair improves the outcome of surgery for mitral regurgitation. A multivariate analysis

BACKGROUND

Mitral valve repair has been suggested as providing a better postoperative outcome than valve replacement for mitral regurgitation, but this impression has been obscured by differences in baseline characteristics and has not been confirmed in multivariate analyses.

METHODS AND RESULTS

The outcomes in 195 patients with valve repair and 214 with replacement for organic mitral regurgitation were compared using multivariate analysis. All patients had preoperative echocardiographic assessment of left ventricular function. Before surgery, patients with valve repair were less symptomatic than those with replacement (42% in New York Heart Association functional class I or II versus 24%, respectively; P = .001), had less atrial fibrillation (41% versus 53%; P = .017), and had a better ejection fraction (63 +/- 9% versus 60 +/- 12%, P = .016). After valve repair, compared with valve replacement, overall survival at 10 years was 68 +/- 6% versus 52 +/- 4% (P = .0004), overall operative mortality was 2.6% versus 10.3% (P = .002), operative mortality in patients under age 75 was 1.3% versus 5.7% (P = .036), and late survival (in operative survivors) at 10 years was 69 +/- 6% versus 58 +/- 5% (P = .018). Late survival after valve repair was not different from expected survival. After surgery, ejection fraction decreased significantly in both groups but was higher after valve repair (P = .001). Multivariate analysis indicated an independent beneficial effect of valve repair on overall survival (hazard ratio, 0.39; P = .00001), operative mortality (odds ratio, 0.27; P = .026), late survival (hazard ratio, 0.44; P = .001), and postoperative ejection fraction (P = .001).

CONCLUSIONS

Valve repair significantly improves postoperative outcome in patients with mitral regurgitation and should be the preferred mode of surgical correction. The low operative mortality is an incentive for early surgery before ventricular dysfunction occurs.

Echocardiographic prediction of left ventricular function after correction of mitral regurgitation: results and clinical implications

OBJECTIVES

This study attempted to determine the incidence, prognosis and predictability of postoperative left ventricular dysfunction in patients undergoing correction of mitral regurgitation.

BACKGROUND

Left ventricular function in patients with mitral regurgitation is altered by loading conditions and is difficult to assess. Predictive value of preoperative variables on postoperative left ventricular function and the role of echocardiography are uncertain.

METHODS

In 266 patients undergoing correction of mitral regurgitation between 1980 and 1989, left ventricular function was echocardiographically assessed preoperatively (within 6 months) and postoperatively (within 1 year).

RESULTS

After correction of mitral regurgitation, left ventricular ejection fraction decreased significantly ([mean +/- SD] 50% +/- 14% vs. 58% +/- 13%, p < 0.0001). Postoperative left ventricular dysfunction (ejection fraction < 50%) was frequent (41% of patients) and carried a poor prognosis (at 8 years survival, 38% +/- 9% vs. 69% +/- 8%, p < 0.0001). Four preoperative echocardiographic variables showed good correlation with postoperative ejection fraction: preoperative ejection fraction (r = -0.70), systolic diameter (r = -0.63), diameter/thickness ratio (r = -0.64) and end-systolic wall stress (r = -0.62) (all p < 0.0001). With multivariate analysis, ejection fraction (p = 0.0001) and systolic diameter (p = 0.0005) were independent predictors of postoperative ejection fraction, and angiographic variables provided no incremental predictive power. In addition to echocardiographic variables, recent regurgitation, functional class and coronary artery disease were also independent predictors of postoperative ejection fraction.

CONCLUSIONS

After surgical correction of mitral regurgitation, left ventricular dysfunction is frequent and carries a poor prognosis. Postoperative ejection fraction can be predicted by echocardiographic preoperative ejection fraction and systolic diameter. Recent onset of regurgitation, mild or no symptoms, and absence of coronary artery disease are independent and favorable predictors of postoperative ejection fraction. These results should lead to consideration of surgical correction at an earlier stage.

Overestimation of severity of ischemic/functional mitral regurgitation by color Doppler jet area

Color Doppler jet analysis is widely used to characterize the degree of mitral regurgitation (MR), but the validity of this approach in patients with ischemic or functional MR has not been established. It was hypothesized that color Doppler jet area overestimates the magnitude of MR of ischemic or functional origin. The severity of isolated MR in 170 patients was measured by using Doppler/echocardiography. Group 1 (n = 58) included patients with ischemic or functional MR, and group 2 (n = 112) included those with organic MR. The regurgitant jet area and 2 methods of quantitation (quantitative Doppler and quantitative 2-dimensional echocardiography) were measured simultaneously. In group 1, color jet area was larger (10.6 +/- 5.3 vs 8.2 +/- 5.3 cm2, p = 0.004) but corresponded to a smaller regurgitant volume and regurgitant fraction by quantitative Doppler (28 +/- 14 vs 55 +/- 46 ml, p = 0.0006, and 31 +/- 12% vs 38 +/- 20%, p = 0.02, respectively) and by quantitative 2-dimensional echocardiography (22 +/- 11 vs 49 +/- 40 ml, p < 0.0001, and 27 +/- 12% vs 36 +/- 20%, p = 0.005, respectively). Enlargement of the left-sided chambers was more marked in group 1. In ischemic/functional MR, the diagnosis of severe regurgitation by color Doppler (jet area > 8 cm2) was confirmed by quantitative methods (regurgitant fraction > or = 50%) in only 6% to 11% of patients, whereas it was confirmed in 60% to 73% of patients with organic MR (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic prediction of survival after surgical correction of organic mitral regurgitation

BACKGROUND

Left ventricular dysfunction is a frequent cause of death after successful surgical repair of mitral regurgitation. The role of preoperative echocardiographic left ventricular variables in the prediction of postoperative survival and thus their clinical implications remain uncertain.

METHODS AND RESULTS

The survival of 409 patients operated on between 1980 and 1989 for pure, isolated, organic mitral regurgitation and with a preoperative echocardiogram (within 6 months of operation) was analyzed. The overall survival was 75% at 5 years (90% of expected), 58% at 10 years (88% of expected), and 44% at 12 years (73% of expected). Operative mortality was 6.6% and markedly improved from 1980 to 1984 (10.7%) to 1985 to 1989 (3.7%). Multivariate analysis showed that age (P = .0003), date of operation (P = .003), and functional class (P = .016) but not left ventricular function were predictors of operative mortality. In the most recent period (1985 to 1989), operative mortality was 12.3% in patients age 75 years or older and 1.1% in patients younger than 75 years. Late survival was analyzed in the operative survivors. Multivariate analysis showed that the most powerful predictor was echocardiographic ejection fraction (EF) (P = .0004), followed by age (P = .0031), creatinine level (P = .0062), systolic blood pressure (P = .0164), and presence of coronary artery disease (P = .0237). The late survival at 10 years was 32 +/- 12% for patients with EF < 50%, 53 +/- 9% for EF 50% to 60%, and 72 +/- 4% for EF > or = 60%. The hazard ratio compared with EF > or = 60% was 2.79 (95% confidence interval, 1.65 to 4.72) for EF < 50% and 1.81 (95% confidence interval, 1.11 to 2.95) for EF 50% to 60%. Echocardiographic EF remained the best predictor of late survival, even when combined with left ventricular angiographic variables. The survival of patients with EF > or = 60% was 100% of expected at 10 years but was better in patients in class I or II than in those in class III or IV (82 +/- 6% versus 59 +/- 6%, respectively, at 10 years; P = .0021). The preoperative predictors of operative and late mortality remained significant independent of the type of surgical correction performed in combined multivariate analyses.

CONCLUSIONS

In organic mitral regurgitation, (1) operative mortality has markedly decreased recently, being at a low 1.1% in patients younger than 75 years, and is predicted by age and symptoms and not by left ventricular function, and (2) left ventricular EF measured by echocardiography is the most powerful predictor of late survival. These results suggest that surgical treatment should be considered early, even in the absence of severe symptoms, in patients with severe mitral regurgitation, before left ventricular dysfunction occurs.

Effective regurgitant orifice area: a noninvasive Doppler development of an old hemodynamic concept

OBJECTIVES

The purpose of this study was to determine the feasibility, relation to other methods and significance of the effective regurgitant orifice area measurement.

BACKGROUND

Assessment of the severity of valvular regurgitation (effective regurgitant orifice area) has not been implemented in clinical practice but can be made by Doppler echocardiography.

METHODS

Effective regurgitant orifice area was calculated by Doppler echocardiography as the ratio of regurgitant volume/regurgitant jet time-velocity integral and compared with color flow Doppler mapping, angiography, surgical classification, regurgitant fraction and variables of volume overload.

RESULTS

In 210 consecutive patients examined prospectively, feasibility improved from the early to the late experience (65% to 95%). Effective regurgitant orifice area was 28 +/- 23 mm2 (mean +/- SD) for aortic regurgitation (32 patients), 22 +/- 13 mm2 for ischemic/functional mitral regurgitation (50 patients) and 41 +/- 32 mm2 for organic mitral regurgitation (82 patients). Significant correlations were found between effective regurgitant orifice and mitral jet area by color flow Doppler mapping (r = 0.68 and r = 0.63, p < 0.0001, respectively) and angiographic grade (r = 0.77, p = 0.0004). Effective regurgitant orifice area in surgically determined moderate and severe lesions was markedly different in mitral regurgitation (35 +/- 12 and 75 +/- 33 mm2, respectively, p = 0.009) and in aortic regurgitation (21 +/- 8 and 38 +/- 5 mm2, respectively, p = 0.08). Strong correlations were found between effective regurgitant orifice area and variables reflecting volume overload. A logarithmic regression was found between effective regurgitant orifice area and regurgitant fraction, underlining the complementarity of these indexes.

CONCLUSIONS

Calculation of effective regurgitant orifice area is a noninvasive Doppler development of an old hemodynamic concept, allowing assessment of the lesion severity of valvular regurgitation. Feasibility is excellent with experience. Effective regurgitant orifice area is an important and clinically significant index of regurgitation severity. It brings additive information to other quantitative indexes and its measurement should be implemented in the comprehensive assessment of valvular regurgitation.

Amplitude-weighted mean velocity: clinical utilization for quantitation of mitral regurgitation

OBJECTIVES

The purpose of this study was to determine the clinical usefulness of the amplitude-weighted mean velocity method for quantitation of mitral regurgitation.

BACKGROUND

Amplitude-weighted mean velocity is a nonvolumetric method for calculating the mitral regurgitant fraction. Its previous validation at one center mandated an independent assessment of its usefulness and limitations.

METHODS

In 56 patients with and 16 patients without mitral regurgitation, the regurgitant fraction was measured simultaneously by amplitude-weighted mean velocity, quantitative Doppler study and quantitative two-dimensional echocardiography. In 16 patients, multiple gain settings were used to determine the influence of this variable on amplitude-weighted mean velocity.

RESULTS

In patients without regurgitation, amplitude-weighted mean velocity showed more scattering of regurgitant fraction (-18% to 23%) than Doppler (p = 0.016) or two-dimensional echocardiography (p = 0.022). The absolute value of regurgitant fraction was (mean +/- SD) 8 +/- 6%, 4 +/- 2% and 4 +/- 3%, respectively (p = NS). With increasing gain, the amplitude-weighted mean velocity mitral and aortic integrals increased, but the calculated regurgitant fraction remained unchanged. In patients with mitral regurgitation, significant correlation was found between amplitude-weighted mean velocity and Doppler study (r = 0.79, p = 0.0001) and between amplitude-weighted mean velocity and two-dimensional echocardiography (r = 0.76, p = 0.0001) for calculated regurgitant fraction, but the standard error of the estimate (12%) was large.

CONCLUSIONS

The amplitude-weighted mean velocity-calculated regurgitant fraction is gain independent, whereas the aortic and mitral integrals are gain dependent. Compared with Doppler and two-dimensional echocardiography, it shows more scattering of values in patients without regurgitation, but the methods correlate significantly in patients with mitral regurgitation. Amplitude-weighted mean velocity can be used as a simple adjunctive tool for comprehensive, noninvasive quantitation of mitral regurgitation.

Multiplane transesophageal echocardiography: image orientation, examination technique, anatomic correlations, and clinical applications

Multiplane transesophageal echocardiography (TEE) consists of a single ultrasound array or imaging sector that can be rotated around the long axis of the ultrasound beam typically in a 180 degrees arc. This capability produces a circular (conical) continuum of tomographic two-dimensional images. The principal advantage of multiple TEE is that the transducer can be rotated to an image-specific orientation and critically optimized. Thus, manipulation of the transducer is less complex than with the biplane technique, and user adaptation is considerably enhanced. The logical image notation (that is, degrees of rotation) and orientation are described in this report. A step-by-step approach to the multiplane TEE examination, which evolved from our initial experience with 400 consecutive patients, is correlated with accompanying tomographic anatomic corroboration. The unique clinical applications are discussed and related to the amplification of diagnostic information. Although the multiplanar TEE transducer is relatively large, all adult patients who weigh 40 kg or more can be examined. No major complications occurred in our initial experience with this promising new technology.