Pulsed Doppler echocardiography in the diagnosis and estimation of severity of aortic insufficiency

Pulsed Doppler Echocardiography: An Historical Perspective

Over the past six decades, echocardiography has evolved into an important technique for not only imaging cardiac structures, but also, by employing the Doppler equation, for assessing cardiac blood flow and tissue velocities. This review focuses on pulsed Doppler echocardiography: its principles, early development, and clinical applications. Important clinical applications include: (1) measurement of flow velocities, stroke volumes, and regurgitant and shunt volumes; (2) assessment of time intervals, e.g., pulmonary artery acceleration time as a measure of pulmonary artery pressure and resistance or the timing of mitral regurgitation in hypertrophic cardiomyopathy; (3) detection of turbulent flow in regurgitation, stenoses, and shunts, enhanced by the implementation of color Doppler; and (4) evaluation of left ventricular diastolic function in conjunction with pulsed tissue Doppler and deformation (strain) measurements.

Directional Doppler in Cardiology: A 50-Year Journey

In 1968, while cardiologists were focused on cardiac structures imaged by ultrasound, Daniel Kalmanson in Paris, France, devised a new ultrasonic modality, directional continuous-wave Doppler, enabling him to record instantaneous cardiovascular blood flow velocities with recognition of their direction (relative to the transducer) in vessels. An innovative presentation of Doppler data also made velocity traces physiologically understandable. Following the noninvasive study of the arterial and venous beds, flow velocity in the right (1969) and left (1970) cardiac chambers was studied by means of a directional Doppler catheter. The curtain was then raised for the renewal of our pathophysiologic understanding of cardiac dynamics and the adoption of a new methodology. Technological evolution paved the way for clever researchers to pioneer important advances, diversifying the technique. Guided by the early principles, which are still valid in 2018, directional Doppler finally gained acceptance from the entire scientific community.

The Integration of Doppler Ultrasound With Two-Dimensional Echocardiography and the Noninvasive Cardiac Hemodynamic Revolution of the 1980s

In the 1970s, as cardiac imaging matured from M-mode to two-dimensional echocardiography, investigators in Norway showed that continuous-wave Doppler ultrasonography could be used to accurately measure the mean gradient and pressure half-time for stenotic mitral valves. In the 1980s, continuous-wave Doppler was validated for measurement of the pressure gradient across stenotic aortic valves, and pulsed-wave Doppler combined with two-dimensional echocardiographic imaging was validated for noninvasive measurement of stroke volume and cardiac output. The combination of stroke volume measurement and measurement of the time-velocity integral of flow through the aortic valve was then validated as a means to accurately calculate valve area for patients with stenotic aortic valves or aortic prostheses. This integration of cardiac Doppler ultrasonography with two-dimensional echocardiographic cardiac imaging led to a revolution in noninvasive hemodynamic evaluations, which have replaced invasive hemodynamic evaluations in surgical decision making for most patients with native or prosthetic valvular stenosis.

Quantitative Doppler-Echocardiographic Determination of Regurgitant Volume in Patients with Aortic Insufficiency

Background:

The severity of aortic regurgitation (AR) can be determined by invasive or echocardiographic methods. We systematically compared quantitative invasive and echocardiographic data with semiquantitative invasive grades in a prospective series of patients.

Methods:

Using Doppler-echocardiography we determined the cardiac output over the aortic, pulmonary and mitral valve in 27 patients (20 with, 7 without AR). Aortic regurgitant volume was calculated as the difference between the cardiac output over aortic and pulmonary valve/ mitral valve. During angiography the severity of AR was assessed semiquantitatively by aortography and the regurgitant volume was calculated invasively as the difference between the left- and right ventricular cardiac output.

Results:

The echocardiographically and invasively determined regurgitant blood volume correlated closely (R≈0.8). The regurgitant volume increased with higher angiographic grade but there was significant overlap between adjoining qualitative grades.

Conclusion:

In patients with AR, quantitative echocardiographic and angiographic measurements of the regurgitant volume correlate closely.

Aortic root size and prevalence of aortic regurgitation in elite strength trained athletes

Athletes involved in mainly static or isometric exercise (e.g., weight lifting, power lifting, and bodybuilding) develop pressure overloads due to the high systemic arterial pressure found in this type of exercise. It is hypothesized that chronically elevated aortic wall tension in strength-trained athletes is associated with aortic dilatation and regurgitation. The aim of this study was to evaluate aortic root size and the prevalence of aortic regurgitation in elite strength-trained athletes. The cohort included 100 male athletes (mean age 22.1 +/- 3.6 years; all were finalists or medalists in the country) and 128 healthy age- and height-matched subjects (the control group). Aortic root diameters at end-diastole were measured at 4 locations: (1) the aortic annulus, (2) the sinuses of Valsalva, (3) the sinotubular junction, and (4) the maximal diameter of the proximal ascending aorta. Aortic root diameters at all levels were significantly greater in the strength-trained athletes (p <0.05 for all comparisons). When the strength-trained athletes were divided into quartiles of duration of high-intensity strength training (first quartile: <18 months; second quartile: >18 and <36 months; third quartile: >36 and <54 months; fourth quartile: >54 months), progressive enlargement was found at all aortic diameters. In conclusion, aortic root diameters in all segments of the aortic root were significantly greater in elite strength-trained athletes compared with an age- and height-matched population.

A new echocardiographic method for the assessment of the severity of aortic regurgitation: color M-mode flow propagation velocity

PURPOSE

Echocardiographic Doppler methods widely used in assessment of the severity of aortic regurgitation (AR) are considered sensitive and reliable. However, they all have limitations for quantitation of AR. The color M-mode Doppler flow propagation velocity (FPV) method has been shown to provide useful insights in the evaluation of left ventricular diastolic function and appears to be minimally affected with preload changes. Clinical data regarding the value of FPV in the determination of the significance of valvular insuffiencies are lacking. The purpose of this study was to evaluate the use of FPV in measurement of the severity of AR and to compare its reliability with angiography and other echocardiographic methods.

METHODS

Twenty-nine patients (13 male, 16 female) who had cardiac catheterization for various reasons before echocardiographic evaluation were included. The mean age was 53.6 +/- 13.4 years. At the time of cardiac catheterization, the degree of AR was assessed as mild in 10 patients, as moderate in 12, and as severe in 7. In all patients, FPV measurements of AR were obtained with color M-mode Doppler in the apical 5-chamber view. Regurgitation jet height and its ratio to left ventricular outflow obtained in the parasternal long axis with color flow Doppler, pressure half-time, and slope of AR obtained with continuous wave Doppler in apical 5-chamber view were other echocardiographic methods chosen for comparison.

RESULTS

The mean values of FPV were 93.1 +/- 18.4 cm/s, 49.8 +/- 8.0 cm/s, and 31.7 +/- 4.9 cm/s in severe, moderate, and mild AR groups, respectively (P <.001). Significant correlation was observed between angiographic grades, FPV, pressure half-time, slope, and jet height and ratio to left ventricular outflow (P <.0001, r = 0.93; P <.0001, r = -0.81; P <.0001, r = 0.76; P <.0001, r = 0.92, respectively).

CONCLUSION

FPV is a simple, practical, and reliable method for the quantification of AR.

Acute pulmonary edema in the emergency department: clinical and echocardiographic survey in an aged population

BACKGROUND

This study is aimed at better defining the prevalence of left ventricular dysfunction, atrial fibrillation, and mitral regurgitation in aged patients with cardiogenic acute pulmonary edema.

METHODS

One hundred and twenty-three consecutive patients with acute pulmonary edema (APE) arriving at the emergency department of a peripheral hospital who underwent Doppler echocardiography within 36 hours of admission were reviewed retrospectively.

RESULTS

Left ventricular ejection fraction (LVEF) was normal or near normal (ie, LVEF > or = 40%) in 41.4% (n = 51 patients), and depressed in 58.5% (n = 72). Significant valvular dysfunction was present in 37.4%; mitral regurgitation was the most frequent (22.8%; n = 28). We found a significant positive correlation between systolic blood pressure (SBP) and LVEF (P = 0.003). Within the group of patients presenting with lower SBP (< or = 140 mm Hg), as blood pressure diminished, LVEF also diminished significantly (P = 0.008). In a logistic regression analysis, male sex and SBP of less than 120 mm Hg were found to be the strongest predictors for LVEF < or = 40%, conferring a 2.68- and 2.73-fold risk, respectively (95%CI, 1.19 to -6.00; P = 0.016 and 95%CI, 0.956-7.80; P = 0.061, respectively) compared with female sex and higher SBP groups.

CONCLUSIONS

This study emphasizes that emergency departments should have clear-cut policies for diagnosing and treating acute coronary syndromes and tachyarrhythmias, as being potential treatable causes of APE. Once stabilized, patients should be examined for treatable valvular causes. A further study, of acute echocardiography done upon arrival to the emergency department in patients with APE is warranted.

Value of echocardiographic findings in predicting cardiovascular complications in infective endocarditis

Echocardiography allows the detection of vegetations and estimation of valvular dysfunction in patients with infective endocarditis. The value of echocardiographic findings in predicting cardiac and other vascular complications in infective endocarditis is not well understood. Identification of high-risk patients and early surgery may improve their prognosis. The authors reviewed echocardiographic findings and related them to the development of congestive heart failure, systemic embolism, and the need for surgery or the risk of death without surgery in patients with infective endocarditis. There were 125 episodes of endocarditis in 114 patients (84 episodes [67%] in men) with a mean age +/- standard deviation of 37 +/- 7 years. Vegetations were detected by echocardiography on at least 1 valve in 87 episodes (70%); on the mitral valve in 36 episodes (29%); on the aortic valve in 21 episodes (17%); and on the tricuspid valve in 45 episodes (36%). Severe aortic regurgitation was present in 9 episodes (7%) and severe mitral regurgitation in 4 instances (3%). In 12 of 21 episodes (57%) of vegetations on the aortic valve compared with 15 of 104 patients (14%) without vegetations on the aortic valve (p < 0.001), and in 8 of 9 instances (89%) of severe aortic regurgitation compared with 19 of 116 episodes (16%) without severe aortic regurgitation (p<0.00001), the patients developed congestive heart failure. In 18 of 55 episodes (33%) of vegetations on the aortic/mitral valve compared with 17 of 70 episodes (25%) without vegetations on the aortic valve/mitral valve (p = NS), the patients developed systemic embolism. In 13 of 21 episodes (62%) of vegetations on the aortic valve compared with 19 of 104 episodes (19%) without vegetations on the aortic valve (p < 0.001), and in 8 of 9 episodes (89%) of severe aortic regurgitation compared with 24 of 116 episodes (21%) without severe aortic regurgitation (p < 0.00001), the patients either had surgery or died without surgery. Echocardiographic findings do not reliably predict the risk of systemic embolism in patients with infective endocarditis. Vegetations on the aortic valve and severe aortic regurgitation detected by echocardiography predict a high risk of developing congestive heart failure, and for the combined outcome of requiring surgery, or dying without surgery in infective endocarditis. Early surgery may improve the outlook for survival of these patients.

Aortic regurgitation: quantitative methods by echocardiography

Quantification of aortic regurgitation (AR) is a common and difficult clinical problem. The severity of regurgitation has traditionally been estimated with the use of contrast aortography, which is impractical as a screening tool or for serial examinations. In the past two decades, Doppler echocardiography has emerged as an important tool in the quantification of AR. Pulsed Doppler mapping of the depth of the regurgitant jet into the left ventricle was one of the initial echocardiographic methods used for this purpose. The slope and pressure (or velocity) half-time of continuous-wave Doppler profiles of regurgitant jets are also useful. These Doppler techniques may be used to determine the regurgitant volume or regurgitant fraction in patients with AR. The use of color Doppler to measure the height (or cross-sectional area) of the regurgitant jet relative to the height (cross-sectional area) of the left ventricular outflow tract is both sensitive and specific in the quantification of AR. More recently, the continuity principle has been used to determine the effective aortic regurgitant orifice area, which increases as AR becomes more severe. Although this is a promising tool, calculation of this value is not yet common practice in most echocardiography laboratories. Although no single echocardiographic technique is without limitations, all have some validity, and it is reasonable to use a combination of them to obtain a composite estimate of the severity of AR.

Prospective evaluation of pulmonary edema

OBJECTIVES

To describe the clinical profile and hospital outcome of successive unselected patients with pulmonary edema hospitalized in an internal medicine department.

DESIGN

Prospective, consecutive, unsolicited patients diagnosed with pulmonary edema.

SETTING

An internal medicine department in a 900 tertiary care center.

PATIENTS

A total of 150 consecutive unselected patients (90 males, 60 females; median age, 75 yrs).

RESULTS

Ischemic heart disease, hypertension, various valvular lesions and diabetes mellitus were present in 85%, 70%, 53%, and 52% of patients, respectively. Acute myocardial infarction at admission was observed in 15% of patients. The most common precipitating factors associated with the development of pulmonary edema included: high blood pressure (29%), rapid atrial fibrillation (29%,) unstable angina pectoris (25%), infection (18%), and acute myocardial infarction (15%). Twenty-two patients (15%) were mechanically ventilated. Eighteen patients (12%) died while in the hospital, and the cause of death was cardiac pump failure in 82%. The median hospital stay was 10 days. Predictors for increase rate of in-hospital mortality included: diabetes (p<.05), orthopnea (p<.05), echocardiographic finding of moderate-to-severely depressed global left ventricular systolic function (p<.001), acute myocardial infarction during hospital stay (p<.001), hypotension/shock (p<.05), and the need for mechanical ventilation (p<.001).

CONCLUSIONS

Most patients with pulmonary edema in the internal medicine department are elderly, having ischemic heart disease, hypertension, diabetes, and a previous history of pulmonary edema. The overall mortality is high (in-hospital, 12%) and the predictors associated with high in-hospital mortality are related to left ventricular myocardial function. The long median hospital stay (10 days) and the need for many cardiovascular drugs, impose a considerable cost in the management and health care of these patients.

Heart motion adapted cine phase-contrast flow measurements through the aortic valve

A method for magnetic resonance cine velocity mapping through heart valves with adaptation of both slice offset and angulation according to the motion of the valvular plane of the heart is presented. By means of a subtractive labeling technique, basal myocardial markers are obtained and automatically extracted for quantification of heart motion at the valvular level. The captured excursion of the basal plane is used to calculate the slice offset and angulation of each required time frame for cine velocity mapping. Through-plane velocity offsets are corrected by subtracting velocities introduced by basal plane motion from the measured velocities. For evaluation of the method, flow measurements downstream from the aortic valve were performed both with and without slice adaptation in 11 healthy volunteers and in four patients with aortic regurgitation. Maximum through-plane motion at the aortic root level as calculated from the labeled markers averaged 8.9 mm in the volunteers and 6.5 mm in the patients. The left coronary root was visible in 2-4 (mean: 2.2) time frames during early diastole when imaging with a spatially fixed slice. Time frames obtained with slice adaptation did not contain the coronary roots. Motion correction increased the apparent regurgitant volume by 5.7 +/- 0.4 ml for patients with clinical aortic regurgitation, for an increase of approximately 50%. The proposed method provides flow measurements with correction for through-plane motion perpendicular to the aortic root between the valvular annulus and the coronary ostia throughout the cardiac cycle. Magn Reson Med 42:970-978, 1999.

Discrete subaortic stenosis: assessing adequacy of myectomy by transesophageal echocardiography

BACKGROUND

Membranectomy and myectomy are standard therapy for discrete subaortic stenosis (DS) and are associated with low rates of endocarditis, recurrence, and aortic insufficiency. Extensive myectomy increases risk of complications such as conduction tissue damage and iatrogenic ventricular septal defect (VSD).

MATERIALS AND METHODS

Forty-five adult patients with DS underwent operations in Gulhane Military Medical Academy. Exertional dyspnea was the principal symptom in 29 (64.4%) patients. Transesophageal echocardiography (TEE) was performed routinely in all patients to assess the length and depth of needed myectomy during the perioperative period. Aortic insufficiency (AI) was also noted preoperatively in 31 (68.9%) and a history of aortic valve endocarditis was present in 4 (8.9%) patients.

RESULTS

Myectomy was performed according to TEE measurements. An average of 10 mm in width, 10 mm in depth, and 2.3 mm in length of septal tissue was resected. The mean left ventricle-aorta peak systolic gradient decreased from 70.2+/-9.7 to 17.2+/-2.7 mmHg (p < 0.001). Aortic valve repair was performed in 8 (7.8%) patients and aortic valve replacement in 11 (24.4%) patients at the initial operation. Iatrogenic VSD did not occur in any of the patients. Average postoperative left ventricular outflow tract diameter was 21+/-1.5 mm. Temporary complete heart block occurred in three patients. There was an early residual gradient (36+/-8 mmHg) resulting from temporary hypercontraction that decreased (18+/-5 mmHg) in the first postoperative day.

CONCLUSIONS

Myectomy under perioperative TEE measurement is safe and effective in the treatment of DS. TEE-guided myectomy reduces complications such as complete heart block and iatrogenic VSD.

Long-term follow-up results after balloon dilatation of pulmonic stenosis, aortic stenosis, and coarctation of the aorta: a review

Although immediate and intermediate-term results after balloon dilatation of congenital stenotic lesions of the heart in children are well studied, long-term results have not been documented. Therefore, we reviewed our experience along with the limited published data to address this issue. Late follow-up after balloon pulmonary and aortic valvuloplasty shows low-residual gradients, reintervention-free rates in the mid-80s for pulmonic and in the mid-50s for aortic stenosis, and an increase in degree and prevalence of similunar valve insufficiency. Balloon angioplasty of aortic coarctation results in low-residual gradients, residual hypertension in a minority of patients, low prevalence of aneurysms, and high rates of recurrence in the neonate and young infant. Overall, balloon dilatation is a useful technique in relieving congenital obstructive lesions of the heart in the pediatric patient, but continued study of (1) late pulmonary and aortic insufficiency after valvuloplasty, (2) recurrence and aneurysms after balloon angioplasty of coarctations and, (3) femoral artery compromise in lesions requiring transfemoral artery approach is warranted.

The role of intraoperative echocardiography in valve surgery

The widespread use and popularity of intraoperative echocardiography (IOE) has resulted from advances in cardiac surgery, reparative procedures for valvular heart disease and, most specifically, mitral valve repair. IOE has grown exponentially and is becoming an integral part of the planning and evaluation of many types of surgical procedures such that it is now considered standard of care especially for the perioperative management of patients undergoing mitral and aortic valve repair. This article discusses the application of intraoperative echocardiography and focus specifically on valvular heart disease as this represents the most widely accepted indication for the procedure in current clinical practice.

Quantification of mitral regurgitation with MR phase-velocity mapping using a control volume method

Reliable diagnosis and quantification of mitral regurgitation are important for patient management and for optimizing the time for surgery. Previous methods have often provided suboptimal results. The aim of this in vitro study was to evaluate MR phase-velocity mapping in quantifying the mitral regurgitant volume (MRV) using a control volume (CV) method. A number of contiguous slices were acquired with all three velocity components measured. A CV was then selected, encompassing the regurgitant orifice. Mass conservation dictates that the net inflow into the CV should be equal to the regurgitant flow. Results showed that a CV, the boundary voxels of which excluded the region of flow acceleration and aliasing at the orifice, provided accurate measurements of the regurgitant flow. A smaller CV provided erroneous results because of flow acceleration and velocity aliasing close to the orifice. A large CV generally provided inaccurate results because of reduced velocity sensitivity far from the orifice. Aortic outflow, orifice shape, and valve geometry did not affect the accuracy of the CV measurements. The CV method is a promising approach to the problem of quantification of the MRV.

Progressive enlargement of the regurgitant orifice in patients with chronic aortic regurgitation

The severity of aortic regurgitation is dependent on the size of the regurgitant orifice, the left ventricular response to volume overload, and the diastolic pressure difference across the aortic valve. The purpose of this study was to test the hypothesis that the aortic regurgitant orifice increases over time in patients with audible chronic aortic regurgitation. To assess serial changes in aortic regurgitant severity by the use of two-dimensional and Doppler echocardiography, 59 patients (29 men and 30 women) with audible chronic aortic regurgitation were prospectively identified and evaluated annually with two-dimensional and Doppler echocardiograms. Patients were followed for a median of 38 months. We measured two separate indicators of the size of the regurgitant orifice: the color Doppler regurgitant jet width and the Doppler-derived regurgitant orifice area. Jet width increased with time (0.5 +/- 0.4 cm at baseline, 0.04 +/- 0.01 cm/year slope, p < 0.001). The regurgitant orifice area also increased (0.12 +/- 0.14 cm2 at baseline, 0.01 +/- 0.01 cm2/year, p = 0.05). Changes in regurgitant orifice area were related to changes in left ventricular end-diastolic dimension (p < 0.001). There were no significant changes in left ventricular chamber dimensions, volumes, and regurgitant volume over time in this cohort. Increases in jet width and orifice area occurred in patients with all degrees of baseline disease severity, with bicuspid or tricuspid leaflet morphology, and with male or female sex. In this prospective study of chronic aortic regurgitation, both jet width and Doppler-derived regurgitant orifice area increased over time. These findings suggest that one factor in the progression of chronic aortic regurgitation is enlargement of the orifice.

Doppler evaluation of aortic regurgitation in children

Doppler indexes have been used successfully to determine the severity of aortic regurgitation (AR) in adults but have not been evaluated systematically in children. To evaluate the accuracy of specific Doppler echocardiographic indexes in assessing the degree of AR in children, 30 children underwent 2-dimensional and Doppler echocardiography within 24 hours of angiography. Patients were divided into 4 groups based on the degree of angiographic AR. Color Doppler jet width, short-axis jet area, jet length, and maximum jet area were measured. AR slope was measured using continuous-wave Doppler. Flow in the abdominal aorta was evaluated using pulsed Doppler. Doppler indexes were compared with the angiographic grade of AR. Jet width and short-axis jet area were significantly different between groups and showed strong correlation with the angiographic grade. Holodiastolic flow reversal in the abdominal aorta separated 1+ to 2+ from 3+ to 4+ AR (100% sensitivity and 100% negative predictive value for 3+ to 4+ AR). Jet length, maximum jet area, and the ratio of reverse to forward abdominal aortic velocity time integrals correlated with angiography but showed little difference between groups that differed by only 1 angiographic grade. AR slope did not correlate with the angiographic grade. We conclude that in children, color Doppler jet width, short-axis jet area, and holodiastolic abdominal aortic flow reversal are the best predictors of angiographic severity. Use of these indexes may obviate the need for angiography to determine the degree of AR in children.

The importance of slice location on the accuracy of aortic regurgitation measurements with magnetic resonance phase velocity mapping

Although several methods have been used clinically to evaluate the severity of aortic regurgitation, there is no purely quantitative approach for aortic regurgitant volume (ARV) measurements. Magnetic resonance phase velocity mapping can be used to quantify the ARV, with a single imaging slice in the ascending aorta, from through-slice velocity measurements. To investigate the accuracy of this technique, in vitro experiments were performed with a compliant model of the ascending aorta. Our goals were to study the effects of slice location on the reliability of the ARV measurements and to determine the location that provides the most accurate results. It was found that when the slice was placed between the aortic valve and the coronary ostia, the measurements were most accurate. Beyond the coronary ostia, aortic compliance and coronary flow negatively affected the accuracy of the measurements, introducing significant errors. This study shows that slice location is important in quantifying the ARV accurately. The higher accuracy achieved with the slice placed between the aortic valve and the coronary ostia suggests that this slice location should be considered and thoroughly examined as the preferred measurement site clinically.

Slice location dependence of aortic regurgitation measurements with MR phase velocity mapping

Although several methods have been used clinically to assess aortic regurgitation (AR), there is no "gold standard" for regurgitant volume measurement. Magnetic resonance phase velocity mapping (PVM) can be used for noninvasive blood flow measurements. To evaluate the accuracy of PVM in quantifying AR with a single imaging slice in the ascending aorta, in vitro experiments were performed by using a compliant aortic model. Attention was focused on determining the slice location that provided the best results. The most accurate measurements were taken between the aortic valve annulus and the coronary ostia where the measured (Y) and actual (X) flow rate had close agreement (Y = 0.954 x + 0.126, r2 = 0.995, standard deviation of error = 0.139 L/min). Beyond the coronary ostia, coronary flow and aortic compliance negatively affected the accuracy of the measurements. In vivo measurements taken on patients with AR showed the same tendency with the in vitro results. In making decisions regarding patient treatment, diagnostic accuracy is very important. The results from this study suggest that higher accuracy is achieved by placing the slice between the aortic valve and the coronary ostia and that this is the region where attention should be focused for further clinical investigation.

Follow-up results of balloon aortic valvuloplasty in children with special reference to causes of late aortic insufficiency

The purpose of this study was to report on 3- to 9-year follow-up data after balloon aortic valvuloplasty in children and to investigate causes of aortic insufficiency at late follow-up. Although the immediate and short-term results of balloon aortic valvuloplasty have been well documented, little information is available on long-term follow-up results. During a 7.3-year period ending December 1992, 26 young patients, aged 6 weeks to 20 years, underwent balloon aortic valvuloplasty with resultant reduction of peak-to-peak aortic valvar gradient from 71 +/- 20 (mean +/- SD) to 25 +/- 12 mm Hg (p < 0.001). None required immediate surgical intervention. At intermediate-term follow-up, 6 (23%) of 26 had restenosis develop and underwent surgical (4 patients) or repeat balloon valvuloplasty (2 patients). Clinical and echo-Doppler data 3 to 9 years (median 6 years) after balloon valvuloplasty revealed residual peak instantaneous Doppler gradients of 26 +/- 13 mm Hg (p < 0.001), without restenosis beyond what was observed at intermediate-term follow-up. Aortic insufficiency progressed in seven patients. However, none required intervention. Actuarial intervention-free rates at 1, 2, 5, and 9 years were 80%, 76%, 76%, and 76%, respectively. Logistic regression analysis suggested that the degree of Doppler-quantitated aortic insufficiency 1 day after valvuloplasty predicts persistent aortic insufficiency at late follow-up. These data indicate that immediately successful balloon aortic valvuloplasty in children yields a residual gradient of < or = 36 mm Hg at a median of 6 years of follow-up in most patients and an intervention-free rate at 9 years of 76%. Restenosis occurs but can be treated with a repeat intervention with good results. Aortic insufficiency remains stable and does not appear to require intervention, at least during the first decade after balloon dilatation.

Regression of left ventricular dilatation and hypertrophy after aortic valve replacement

The aim of the study was to assess the influence of aortic valve replacement on left ventricular size and muscle hypertrophy according to the type of preexisting valve disease (aortic stenosis, insufficiency or combined disease). The study group consisted of 143 consecutive patients (pts) after aortic valve replacement (109 men, 34 women, mean age 48.1 +/- 10.9 years). Reason for the operation was aortic stenosis in 35 pts, aortic insufficiency in 64 pts and combined disease in 44 pts. Echocardiography was performed before surgery, 1 month and 1 year after operation, and yearly during 5-year follow-up. Transvalvular aortic pressure gradients decreased significantly after valve replacement in all subsets without further changes during follow-up (Pmax (mmHg): from 54.2 +/- 20.7 to 17.9 +/- 9.6 in combined disease pts, from 72.3 +/- 19.9 to 21.6 +/- 14.6 in aortic stenosis and from 34.5 +/- 24.2 to 15.6 +/- 11.3 in aortic insufficiency pts, respectively, P < 0.0005). One year after surgery the diastolic dimension of the left ventricle decreased significantly in all subjects, whereas the systolic dimension only in aortic insufficiency and combined disease pts (from 44 +/- 11.8 to 31.6 +/- 5.4 mm, P < 0.001 and from 41.9 +/- 11.5 to 33 +/- 6.7 mm, P < 0.05, respectively). Further decrease of both diastolic and systolic dimensions was observed only in the aortic insufficiency group. Ejection fraction of left ventricle increased only in combined disease pts (from 51.6 +/- 10% to 56.8 +/- 8.2%, P < 0.05). Wall thickness of the left ventricle decreased 1 year after valve replacement only in the aortic stenosis group and in further follow-up in the aortic stenosis and combined disease group. Normalization of left ventricular size is observed in more than 90% of patients during 5-year follow-up as opposed to left ventricular muscle hypertrophy, regressed only in less than a half of the study population. In patients with aortic valve disease the greatest hemodynamic improvement is observed 1 year after valve replacement. This is expressed by marked reduction of the left ventricular dimensions and wall thickness, without significant improvement of the ejection fraction. Further regression of left ventricle dimensions occurs in patients operated on due to predominant valve insufficiency, whereas regression of left ventricular hypertrophy is observed in patients with preexisting valvular stenosis.

Effect of hypertension on aortic root size and prevalence of aortic regurgitation

Although early reports suggested that hypertension predisposed to aortic root enlargement and consequent aortic regurgitation, more recent pathological and M-mode echocardiographic studies have not found an association between hypertension and aortic enlargement when age is considered. These discrepancies may partially reflect methodological shortcomings in the accuracy and reproducibility of aortic and blood pressure measurements. Therefore, we measured two-dimensional echocardiographic diameters of the aortic root at four locations and compared findings with ambulatory and resting blood pressures and measures of body size in 110 normotensive and 110 hypertensive men and women matched for age and sex. Aortic diameters at the anulus (2.41 +/- 0.29 versus 2.34 +/- 0.24 cm, P = .06) and sinuses (3.47 +/- 0.44 versus 3.37 +/- 0.36 cm, P = .08) were marginally higher, whereas diameters at the supra-aortic ridge (2.94 +/- 0-38 versus 2.81 +/- 0.32 cm, P < .01) and ascending aorta (3.26 +/- 0.45 versus 3.11 +/- 0.32 cm, P < .01) were significantly increased in hypertensive subjects. Aortic diameters increased with increasing quartiles of diastolic and systolic pressures, particularly at the supra-aortic ridge and ascending aorta. In multivariate analyses, blood pressure remained an independent determinant of distal aortic diameters after body size and age were considered. Aortic regurgitation was seen in 5 normotensive and 7 hypertensive subjects and did not differ in severity. Thus, hypertension is associated with a slight increase in aortic root size, most notably of the supra-aortic ridge and proximal ascending aorta. Although dilatation at the commissural attachment might be expected to predispose to an increase in aortic regurgitation, we did not detect such a difference in this population of healthy, asymptomatic individuals.

Aortic valve regurgitation after surgical versus percutaneous balloon valvotomy for congenital aortic valve stenosis

To compare characteristics of aortic regurgitation (AR), the results of 213 procedures (110 balloon aortic valvotomies [BAV] and 103 surgical aortic valvotomies [SAV]) for treatment of congenital aortic valve stenosis were reviewed. These procedures were performed in 187 patients from June 1981 to September 1993. Echocardiograms recorded immediately before, within 6 months afterward, and at latest follow-up were compared. Color Doppler was used to assess the degree of AR and was quantified as the ratio of the regurgitant jet width to valve annulus, the jet width ratio. Whereas BAV patients were older (median age 5.7 years vs 3 months; p = 0.0001), there was no significant difference in median follow-up interval (3.1 years [range 0.5 to 7.2] for BAV vs 3.6 years [range 0.6 to 10.4] for SAV; p = 0.44). The mean balloon-to-annulus ratio for BAV was 0.99 +/- 0.09. An open valvotomy was performed in 83% of surgical cases. Acute systolic gradient reduction and subsequent increase at late follow-up was similar for both groups. Acutely, the mean jet width ratio increased similarly (p = 0.84) for BAV (+9 +/- 15%; p = 0.0001) and SAV (+9 +/- 12%; p = 0.0003) and was not related to age at procedure. At late follow-up, mean jet width ratio further increased significantly in both groups, although there was no difference (p = 0.17) in amount of progression (BAV +10 +/- 12%; p = 0.0001, SAV +15 +/- 13%; p = 0.0002). Thus, BAV and SAV produce AR of similar severity with similar rates of progression.

Severity of Aortic Regurgitation Assessed by Digital Image Processing of Doppler Spectral Recordings

Visual estimates of the intensity of the regurgitant signal (RS) obtained by continuous-wave (CW) Doppler has been used as an indicator of the severity of aortic regurgitation (AR). This study was designed to test this concept quantitatively using digital image processing methods. Twenty-one patients with AR were studied, 14 of whom had concomitant mitral valve disease. Patients with aortic stenosis were excluded. By angiography, 10 patients had mild (grade 1 or 2), 5 had moderate (grade 3), and 6 severe (grade 4) AR. We digitized three well-defined AR envelopes and calculated the mean pixel intensity (MPI) of the RS and the systolic flow signal (SFS) using an offline computer analysis system developed in our laboratory. To negate the effects of different gain settings, the ratio of RS to SFS (RS/SFS ratio) was compared to angiographic grade of AR. Thus, each patient served as his own control. The mean RS/SFS ratio was 0.54 +/- 0.42 SD (range 0.46-0.59) for mild AR, 0.76 +/- 0.71 SD (range 0.65-0.82) for moderate AR, and 0.84 +/- 0.52 (range 0.77-0.92) for severe AR. This RS/SFS ratio correlated well with angiographic severity of AR (r = 0.9). A ratio of <0.6 identified patients with mild AR and >0.6 correlated with moderate-to-severe AR. We conclude that the ratio of the regurgitant to systolic flow CW Doppler signal is an accurate noninvasive indicator of AR severity. (ECHOCARDIOGRAPHY, Volume 13, May 1996)

Transesophageal echocardiographic evaluation of native valvular disease and repair

Surgery for valvular heart disease corrects systolic or diastolic dysfunction of the mitral, aortic, or tricuspid valves. The intraoperative echocardiographic assessment of the native heart valve is aimed at defining the pathology of valve disease, determining the mechanism of valve dysfunction, and quantitating the degree (grade) of valvular stenosis or insufficiency.

Aortic regurgitation in coronary artery bypass grafting: implications for cardioplegia administration

BACKGROUND

Echocardiography can detect aortic regurgitation (AR) that may interfere with the adequate delivery of cardioplegia solution to the myocardium during cardiac operation. When aware of this lesion, the surgeon can modify the operative technique accordingly. We sought to evaluate the ability of intraoperative transesophageal echocardiography to detect AR and to correlate the severity of the lesion with the need for retrograde cardioplegia administration.

METHODS

Eighty-four consecutive patients undergoing coronary artery bypass grafting were evaluated. When AR was noted by intraoperative transesophageal echocardiography, a cannula was placed in the coronary sinus for possible retrograde cardioplegia administration. The surgeon was unaware of the severity of AR. After operation, the severity of AR was quantitated using the ratio of the regurgitation jet width to the left ventricular outflow tract diameter.

RESULTS

The AR patients who required retrograde cardioplegia had a significantly higher ratio of regurgitation jet width to left ventricular outflow tract diameter than those AR patients who did not (0.36 +/- 0.06 versus 0.19 +/- 0.06, p < 0.005).

CONCLUSIONS

Transesophageal echocardiography can provide accurate information regarding the presence and severity of AR. The calculated severity of AR on transesophageal echocardiography is associated with the need for retrograde cardioplegia administration.

Cardiac valve involvement in systemic lupus erythematosus and primary antiphospholipid syndrome: lack of correlation with antiphospholipid antibodies

The aim of this study was to determine the prevalence of cardiac valve disease in systemic lupus erythematosus or in patients with primary antiphospholipid syndrome and to assess the role of the antiphospholipid antibodies as risk factor for endocardial lesions. We studied 39 consecutive patients with systemic lupus erythematosus (mean age 34 +/- 12 years, 38 female and one male), 20 women with primary antiphospholipid syndrome (mean age 32 +/- 4 years) and 20 normal subjects (mean age 35 +/- 8 years, 15 female and five male). All patients with primary antiphospholipid syndrome had increased levels of serum anticardiolipin antibodies and recurrent fetal abortions; some of them also had arterial and/or venous thrombosis and/or thrombocytopenia. M-mode, two-dimensional and Doppler echocardiography were performed in all patients. IgG anticardiolipin antibodies were measured by an enzyme-linked immunosorbent assay. Valvular lesions were observed in 15 patients (38%) with systemic lupus erythematosus. These abnormalities included: mitral valve thickening or vegetation, mitral valve prolapse and aortic valve vegetation; mitral, aortic and tricuspid regurgitation; mitral stenosis. None of the patients with primary antiphospholipid syndrome and of the normal subjects was found to have valvular abnormalities. In systemic lupus erythematosus, high levels of anticardiolipin antibodies were detected in 73% of the patients with valvular lesions and in 67% of the patients without valvular lesions (P > 0.05). We conclude that valvular involvement is frequent in patients with systemic lupus erythematosus but it is apparently unrelated to antiphospholipid autoimmunization.

Mitral and aortic regurgitation in 84 patients with mucopolysaccharidoses

In echocardiographic and necropsy studies nodular thickening of the mitral valve and, less frequently, of the aortic valve has been found in 60%-90% of patients with mucopolysaccharidoses (MPS). Little is known about the haemodynamic consequences of these morphological changes. In this study 84 unselected patients with different enzymatically proven MPS and 84 age and sex matched, healthy persons were studied prospectively by colour Doppler flow mapping. The patients' age ranged from 1 to 47 years (median 8.1 years). Mitral and aortic regurgitation were defined as a holosystolic or holodiastolic jet originating from the valve into the left atrium or the left ventricular outflow tract, respectively, with peak velocities exceeding 2.5 m/s. Of the 84 patients with satisfactory studies, mitral regurgitation was detected in 64.3% and aortic regurgitation in 40.5%, respectively. Regurgitation was severe in 4.8% of mitral valves and 8.3% of aortic valves. The frequency of aortic and/or mitral regurgitation was 75% in all patients, 89% in MPS I, 94% in MPS II, 66% in MPS III, 33% in MPS IV, and 100% in MPS VI. Combined mitral and aortic regurgitation was present in 29% of our patients. None of the control persons showed mitral or aortic regurgitation.

CONCLUSION

Aortic and mitral regurgitation are more frequent in patients with MPS than previously thought and that therefore these patients should have regular colour Doppler flow mapping and antibiotic prophylaxis when required.

Postoperative follow-up of fibromuscular subaortic stenosis

OBJECTIVES

This study attempted to determine whether early subaortic resection at lower levels of obstruction reduces the rate of recurrence of subaortic stenosis or reduces secondary damage to the aortic valve, or both.

BACKGROUND

Fibromuscular subaortic stenosis is a progressive condition, and at present it is unclear whether early operation reduces the recurrence rate along with decreasing the incidence of aortic insufficiency.

METHODS

Thirty-seven patients with fibromuscular subaortic stenosis and no other significant cardiac abnormality who underwent open subaortic resection were evaluated. The preoperative, early and late postoperative catheterization or echocardiographic findings as well as the operative reports were reviewed. The median age at operation was 6.4 years (range 1.1 to 17.3). The entire group has been followed up postoperatively for a median of 5.2 years (range 1.1 to 11). Mean systolic gradients across the left ventricular outflow tract were used for the purpose of this study.

RESULTS

There was a significant correlation between the preoperative mean systolic gradient and the incidence of preoperative aortic regurgitation and late postoperative aortic valve thickening as well as the incidence and degree of late postoperative aortic regurgitation. Late postoperative gradient and degree of aortic regurgitation correlated significantly with the follow-up interval. Aortic regurgitation was progressive in some patients despite subaortic resection. A preoperative mean gradient > 30 mm Hg provided a reasonable cutoff for the likelihood postoperatively of needing a reoperation, having a postoperative shelf, a thickened aortic valve, moderate aortic regurgitation or a gradient of > 10 mm Hg.

CONCLUSIONS

Our results suggest that although early subaortic resection may not reduce the rate of recurrence of fixed subaortic stenosis, it is likely to reduce acquired damage to the aortic valve.

Alterations in transmitral flow dynamics in patients with early mitral valve closure and aortic regurgitation

Ten patients with severe aortic regurgitation (AR) and early diastolic mitral closure demonstrated by M-mode echocardiography (group I) were compared to 10 age-matched patients with severe AR and normal timing of mitral closure to quantify the accompanying alterations in transmitral flow dynamics assessed by pulsed Doppler echocardiography. Transmitral filling period expressed as a fraction of the time available for diastolic filling was significantly shortened in group I patients relative to group II patients (0.50 +/- 0.10 vs 1.04 +/- 0.09, p < 0.001) because early mitral closure truncated transmitral filling and obliterated the atrial contribution to left ventricular filling. The rapid diastolic filling period normalized for the time available for diastolic filling was also shortened for group I patients relative to group II patients (0.49 +/- 0.11 vs 0.64 +/- 0.19; p < 0.05). Early mitral closure in group I patients was functionally incomplete because 9 of the 10 patients had diastolic mitral regurgitation, which was not detected in any patients in group II (p < 0.001). Thus the group I patients with early mitral closure and severe aortic regurgitation had truncated transmitral inflow and diastolic mitral regurgitation. These patients had higher pulmonary capillary wedge pressures (32 +/- 6 vs 11 +/- 9 mm Hg; p < 0.001) and more severe functional limitation (p < 0.001) than group II patients.

A simplified method for determining regurgitant fraction by Doppler echocardiography in patients with aortic regurgitation

OBJECTIVES

This study attempted to develop and validate a simple method for calculating aortic regurgitant fraction by use of pulsed wave Doppler echocardiography.

BACKGROUND

Although several investigators have been able to determine aortic regurgitant fraction by Doppler echocardiography, the methods used require accurate determination of the cross-sectional areas of intracardiac sites at which the volumetric flow is calculated.

METHODS

Our concept was based on a constant relation that exists between the cross-sectional area of the left ventricular outflow tract and the mitral valve annulus in normal subjects. To verify this, we used Doppler echocardiography to measure the flow velocity integral of the left ventricular outflow tract and the mitral annulus in the apical view in 50 normal subjects (32 men, 18 women, mean age 34 years).

RESULTS

Close correlation (r = 0.95) was observed between the flow velocity integral (FVI) of the outflow tract (OT) and that of the mitral annulus (MA): FVIMA/FVIOT = 0.77. Because mitral flow equals aortic flow in normal subjects, the ratio of the cross-sectional area of the mitral annulus to that of the outflow tract was 1/0.77. In patients with aortic regurgitation, the regurgitant fraction (RF) = (Aortic flow-Mitral flow)/Aortic flow = 1-Mitral flow/Aortic flow. Substituting 0.77 for the area component of flow, RF = 1-(1/0.77).(FVIMA/FVIOT). To evaluate the accuracy of this method, we compared the regurgitant fraction derived by Doppler echocardiography with that from catheterization findings in 20 patients with aortic regurgitation (an isolated lesion was found in 14). The regurgitant fraction by catheterization was the difference between total (angiographic) and forward (thermodilution) stroke volumes as a percent of total flow. Good correlation was observed between catheterization and Doppler regurgitant fraction (r = 0.88, SEE 9%, p < 0.01).

CONCLUSIONS

Thus, regurgitant fraction can be estimated from Doppler echocardiography in patients with aortic regurgitation by a method that requires only measurements of the flow velocity integral from the mitral annulus and left ventricular outflow tract.

Quantitative assessment of valvular function after cardiac transplantation by pulsed Doppler echocardiography

In 31 patients who had undergone cardiac orthotopic transplantation, valvular regurgitation was studied by echocardiographic and pulsed Doppler over 2 years. The first week after cardiac transplantation, transplant recipients had an increase in the severity of tricuspid, mitral (group II), and aortic regurgitation, as well as a greater number of simultaneously regurgitating valves when compared with those in a group of 60 normal subjects of similar age to heart donors: transplant recipients, trivalvular regurgitation 48% (95% confidence interval [CI] 30 to 66) vs control group, 5% (CI 1 to 13; p < 0.001). Moderate-severe tricuspid regurgitation (TR) was the most frequent occurrence (55%, CI 36 to 73) followed by pulmonary (PR) (42%, CI 25 to 61), moderate mitral (MR) (32%, CI 15 to 51), and mild aortic (AR) (23%, CI 10 to 43) regurgitation. These regurgitations were asymptomatic at rest except for TR. TR was associated with right-sided heart failure in 76% of patients in the early postoperative period and controlled with diuretic drugs. This regurgitation correlated with persistence of post-transplant pulmonary hypertension (r = 0.6) and was not related to pulmonary hypertension before cardiac transplant. There was also no relation found between donor ischemia time or episodes of cardiac rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Persistent truncus arteriosus operated during infancy: long-term follow-up

Between July 1974 and October 1988 19 consecutive infants (mean age 2.7 months, range 5 days to 11.7 months) underwent surgical correction for persistent truncus arteriosus by one surgeon (J.L.M.). Continuity between the right ventricle and pulmonary arteries was achieved with an antibiotic-sterilized aortic homograft (diameter 13-18 mm) together with patch closure of the ventricular septal defect. There were 3 early postoperative deaths (16%): 1 patient had severe aortic regurgitation, the other 2 had preoperative cardiac arrests. Of the latter, 1 had suffered severe cerebral damage, and the other developed recurrent pulmonary hypertensive crises and low cardiac output. The 16 survivors have been followed for 3.1-17.3 years (mean 7.8 years). Four patients required subsequent replacement of the homograft for stenosis, aortic valve replacement for regurgitation, or both (3.0, 4.0, 8.5, and 12.0 years postoperatively). Of the 16 survivors, 15 are in NYHA class I. Of the 13 patients who have not had aortic valve surgery, 9 have no evidence of stenosis or regurgitation. In the 14 children with the original homograft the median of the residual peak gradient across the right ventricular outflow tract is 15 mmHg (range 10-40 mmHg), and no patient has severe homograft regurgitation at follow-up. Repair of persistent truncus arteriosus has been achieved with low early mortality and no late mortality, which reflects excellent long-term function of the homograft. Furthermore, if truncal valve function is good at presentation, patients are unlikely to require aortic valve surgery.

Prognostic significance of the pattern of aortic root dilation in the Marfan syndrome

OBJECTIVES

The present study examines the incidence of aortic complications (dissection, marked dilation requiring surgery or progressive moderate to severe aortic regurgitation) and their relation to clinical features and aortic root morphology in patients with the Marfan syndrome.

BACKGROUND

Considerable phenotypic variability exists in the Marfan syndrome, and the prospective prediction of the risk for aortic complications in individual patients remains elusive.

METHODS

One hundred thirteen patients with the Marfan syndrome underwent anthropometric and echocardiographic evaluation and were followed-up for 49 +/- 24 (mean +/- SD) months. Aortic root dilation was defined as localized when confined to the sinuses of Valsalva (based on two-dimensional echocardiographic confidence limits utilizing age and body size) and generalized if dilation additionally involved the supraaortic ridge and proximal ascending aorta.

RESULTS

Aortic root dilation was present in 80% of patients and was localized in 28% and generalized in 51%. Aortic complications occurred during follow-up in none of 23 patients with normal initial aortic size, in 2 (6%) of 32 patients with initially localized dilation and in 19 (33%) of 58 patients with generalized dilation (p < 0.0005). Complications were associated with larger initial aortic size (p < 0.00005), higher systolic blood pressure (p < 0.005), height (p < 0.05), aortic growth rate (p < 0.05) and older age (p < 0.01). The only independent predictor of aortic complications was initial aortic root size (p < 0.005). However, when aortic size, one of the indications for surgical referral, was excluded from analyses, the only independent predictor of aortic complications was generalized aortic dilation (p < 0.005).

CONCLUSIONS

The present study indicates that generalized aortic root dilation is a potent marker of an increased risk for subsequent aortic complications in Marfan syndrome.

Quantification of aortic regurgitation by magnetic resonance velocity mapping

The use of magnetic resonance (MR) velocity mapping in the quantification of aortic valvular blood flow was examined in 10 patients with angiographically verified aortic regurgitation. MR velocity mapping succeeded in identifying and quantifying the regurgitation in all patients, and the regurgitant volume determined with MR velocity mapping agreed well with the grade obtained by aortic root angiography (p < 0.02). The accuracy in quantification of the aortic valvular flow rate was demonstrated by a significant correlation between the stroke volume (ml) measured by MR velocity mapping and calculated from MR imaging of the left ventricular end-diastolic and end-systolic volumes in eight patients (Y = 0.89 x X + 11, r = 0.97, p < 0.001). This finding was confirmed by a good agreement between the net cardiac output (L/min) quantified with MR velocity mapping and simultaneous 125I-indicator dilution measurement in all subjects (Y = 0.89 x X + 0.08, r = 0.82, p < 0.01). In conclusion, MR velocity mapping may be used as a noninvasive tool in the quantification of aortic regurgitation.

Progression of aortic valve dysfunction in 51 adult patients with congenital bicuspid aortic valve: assessment and follow up by Doppler echocardiography

OBJECTIVE

To assess the pattern and progression of aortic valve dysfunction by serial Doppler echocardiographic examinations in ambulatory adult patients with congenital bicuspid aortic valve.

DESIGN AND SETTING

Retrospective analysis of patients referred for Doppler echocardiography over a four year period.

SUBJECTS

Fifty one adult patients with echocardiographic diagnosis of congenital bicuspid aortic valve had serial Doppler echocardiographic studies at least six months apart. There were 40 men and 11 women with a mean age of 36 years.

MAIN OUTCOME MEASURE

Doppler echocardiographic values of aortic valve dysfunction. Cardiac events including endocarditis and aortic valve replacement were also evaluated.

RESULT

Coarctation was present in five patients. 31 (61%) patients had a functionally normal bicuspid aortic valve defined as a mean gradient < 25 mm Hg and mild regurgitation. Significant aortic regurgitation was present in 15 patients (moderate in 12 and severe in three). Three patients had isolated aortic stenosis and two patients had combined aortic valve dysfunction. At a median follow up of 21 months (range six to 46 months), six patients had aortic valve surgery (one for aortic stenosis, three for aortic regurgitation, and two for endocarditis). Only 22 patients (43%) continued to have a functionally normal aortic valve.

CONCLUSION

In this cohort of fairly young patients, aortic regurgitation is more common than aortic stenosis. Progression of aortic valve dysfunction occurs in patients with pre-existing valve dysfunction and even in those with normal aortic valve function at the initial echocardiographic examination.

Value and limitations of Doppler echocardiographic determination of mitral valve area in Lutembacher syndrome

OBJECTIVES

Our objective was to compare the Doppler pressure half-time, Doppler continuity equation and two-dimensional echocardiographic planimetric methods of estimating mitral valve area in Lutembacher syndrome.

BACKGROUND

Fluid dynamics theory predicts that mitral pressure half-time varies inversely with mitral valve area and directly with net chamber compliance and the peak early diastolic transmitral gradient in pure mitral stenosis. The effects of an atrial shunt on these interrelations have not been investigated.

METHODS

Correlation and agreement between mitral valve area estimates obtained by the three methods and that obtained by cardiac catheterization was ascertained in 11 patients with Lutembacher syndrome.

RESULTS

Valve areas determined by planimetry and the continuity equation method correlated and agreed well with catheterization measurements (r = 0.83 and 0.81, respectively). The pressure half-time method consistently overestimated mitral valve area; the extent of overestimation was greater in patients with larger atrial shunts. The hemodynamic pressure half-time was independent of the mitral valve area, chamber compliance and the peak transmitral gradient. It was dependent on the magnitude of the atrial shunt, although the correlation obtained was only fair (r = 0.61).

CONCLUSIONS

These findings suggest that the Doppler pressure half-time method is an inaccurate measure of mitral valve area whenever an atrial shunt coexists with mitral stenosis. Planimetry and the Doppler continuity equation methods yield accurate estimates of mitral valve area in Lutembacher syndrome.

Cardiac involvement in patients with myeloproliferative disorders

INTRODUCTION

To evaluate cardiac involvement in myeloproliferative disorders (MPD), two-dimensional and Doppler echocardiographic studies were performed in 30 patients with MPD.

PATIENTS AND METHODS

There were 18 women and 12 men, with an age range from 35 to 76 years. Eighteen patients had polycythemia vera (PV), 8 had essential thrombocythemia (ET), and 4 had agnogenic myeloid metaplasia (AMM).

RESULTS

Echocardiography revealed valvular lesions in 19 of 30 patients (63%) compared with only 1 of 22 patients (4.5%) in a control group of patients referred for echocardiography to exclude a cardiac source for idiopathic systemic thromboembolism (chi 2 = 13.39, p < 0.001, by chi 2 test with Yates' correction). Valvular lesions were found in 77% of patients with PV, 50% with ET, and 25% with AMM (p = NS). The aortic and mitral valves were the most commonly involved valves, and the most common echocardiographic lesion was leaflet thickening, which was found in 12 patients (40%), followed by vegetations, which were observed in 5 patients (16%). In their past history, 14 of 30 (47%) MPD patients had arterial or venous thrombosis or embolism. Twelve of 19 (63%) patients with valvular lesions had thromboembolism compared with only 2 of 11 (18%) patients without evidence of valvular lesions (chi 2 = 3.99, p < 0.05, by chi 2 test with Yates' correction). Pulmonary hypertension, unrelated to the severity of valvular disease and probably resulting from pulmonary venous occlusion, was found in four patients (13%).

CONCLUSIONS

We conclude that the heart is frequently involved in patients with MPD, particularly when their past history is complicated by a thromboembolic event. Some patients have clinically significant valvular disease. Pulmonary hypertension is another relatively common finding in MPD patients. Echocardiography provides information of clinical significance in MPD patients. A larger number of patients is needed to determine whether the presence of valvular lesions is of prognostic significance and may herald future thromboembolic events.

Semiquantitation of aortic regurgitation by different Doppler echocardiographic techniques and comparison with ultrafast computed tomography

Fourteen patients with chronic aortic regurgitation were studied by several two-dimensional and Doppler echocardiographic methods to determine the severity of aortic regurgitation. Semiquantitation of aortic regurgitation was performed by various color-flow imaging measurements, diastolic half-time of the continuous-wave regurgitation jet, and pulsed-wave velocity curve in the descending aorta. These measurements were compared with regurgitant volume and fraction by ultrafast computed tomography. All Doppler methods demonstrated a significant correlation for severity of aortic regurgitation with regurgitant fraction by ultrafast computed tomographic scanning, but scatter was present with each method. The methods with the closest correlation were at the lowest level of obtainable results. In clinical practice, all Doppler methods must be used to determine the severity of aortic regurgitation.

Calculation of aortic regurgitation orifice area by Doppler echocardiography: an application of the continuity equation

The evaluation of aortic regurgitation by current echocardiographic techniques has been qualitative and load-dependent. The area of the regurgitant orifice, which is theoretically independent of haemodynamic conditions, has not been determined non-invasively. In 20 patients with various degrees of aortic regurgitation, this area was determined by use of the continuity equation applied during diastole. The velocity-time integrals were determined at the supravalvar (VTIs) and regurgitant orifice (VTIj) levels by pulsed and continuous wave Doppler respectively. The cross sectional area at the supravalvar level (As) was also measured by cross sectional echocardiography. The regurgitant orifice is given by: (As x VTIs)/VTIj. Other non-invasive measurements of the aortic regurgitation severity were also recorded: (a) an overall echo score (1-5+) given blindly by two echocardiographers, (b) the maximal proximal jet width by colour Doppler, (c) left ventricular end systolic and end diastolic volumes and left ventricular mass. The regurgitant area ranged from 0.25 to 1.7 cm2 and this area accorded with the overall echo score and the maximal proximal jet width measured by colour Doppler. The aortic regurgitation orifice area can be calculated non-invasively and it may be a quantitative measure of the severity of aortic regurgitation.

The effect of exercise-induced myocardial ischemia on postischemic left ventricular diastolic filling

To determine whether exercise-induced ischemia impairs left ventricular diastolic filling in the postischemic period in humans, 101 men (mean age 57 +/- 10 years) were studied before and 2 h after a symptom-limited thallium-201 tomographic treadmill with pulsed Doppler echocardiography of mitral valve inflow. In the postischemic period 2 h after exercise, diastolic filling was significantly impaired in the ischemia group (reversible thallium defect; n = 24) as reflected by a decrease in the peak early filling velocity (44.5 +/- 10.1 to 39.9 +/- 9.9 cm/s, p less than 0.01), peak early to atrial filling velocity ratio (0.91 +/- 0.27 to 0.76 +/- 0.25, p less than 0.001), and deceleration rate of early filling (281 +/- 104 to 245 +/- 86 cm/s2, p less than 0.01). Similar alterations in the postischemic period occurred in the myocardial infarction-ischemia group (partially reversible defect; n = 28) as seen by a decrease in the peak early filling velocity (47.6 +/- 11.6 to 41.8 +/- 12.0 cm/s, p less than 0.001), peak early to atrial filling velocity ratio (0.84 +/- 0.21 to 0.68 +/- 0.18, p less than 0.001), and early time-velocity integral (7.06 +/- 1.78 to 5.64 +/- 2.07 cm, p less than 0.001). In the control group (no defects; n = 33) and myocardial infarction group (fixed defect; n = 16), diastolic filling was unchanged in the postexercise period. Heart rate and blood pressure were unchanged post-exercise in all groups. Exercise-induced ischemia impairs diastolic filling in the postischemic period in humans.(ABSTRACT TRUNCATED AT 250 WORDS)

The Marfan syndrome: cardiovascular physical findings and diagnostic correlates

Correlations among cardiac symptoms and auscultatory and phonoechocardiographic findings in Marfan syndrome have not been completely defined. A total of 24 patients with Marfan syndrome (16 men and 8 women; mean age 28.2 +/- 8.6 years) were studied. Mitral valve prolapse was noted in 22, of whom 19 had either nonejection systolic click or mitral regurgitation murmur. Mitral regurgitation was noted in 12 patients by Doppler imaging. Aortic root dilatation was noted in 20 patients and aortic regurgitation in six, five of whom had aortic regurgitation murmur (5 of 20 patients had undergone surgery). Proximal aortic dissection was noted in two. Dyspnea (n = 12) was associated with progressive mitral or aortic regurgitation in four, but in the others dyspnea could not be explained by valvular or ventricular abnormalities. Chest pain was related to pneumothorax in five and aortic dissection in two but was not associated with either in 15 patients. Palpitations (n = 12) and lightheadedness (n = 6) were not associated with specific arrhythmias. In conclusion, mitral valve prolapse and aortic root dilatation were the most common cardiovascular abnormalities in Marfan syndrome. Mitral valve prolapse was frequently associated with typical auscultatory findings and symptoms including dyspnea, chest pain, palpitations, and lightheadedness, whereas aortic root dilatation could be clinically silent unless complicated by aortic regurgitation or aortic dissection.

Association of aortic dilation with regurgitant, stenotic and functionally normal bicuspid aortic valves

To determine whether aortic root dilation associated with a bicuspid aortic valve occurs independently of valvular hemodynamic abnormality, aortic root dimensions were measured by two-dimensional echocardiography in 83 adults with a functionally normal (n = 19), mildly regurgitant (n = 26), severely regurgitant (n = 27) or stenotic (n = 11) bicuspid aortic valve and compared with findings in normal subjects matched for age and gender. Aortic root measurements were made at four levels: anulus, sinuses of Valsalva, supraaortic ridge and proximal ascending aorta. Seventy-one percent of patients with a bicuspid aortic valve were men. When compared with control subjects, all hemodynamic subgroups showed a significantly larger aortic root size at three levels: sinuses of Valsalva, supraaortic ridge and proximal ascending aorta (p less than 0.05 to p less than 0.001). The prevalence of aortic root enlargement among all hemodynamic subgroups ranged from 9% to 59% at the level of the anulus, 36% to 78% at the sinuses, 47% to 79% at the supraaortic ridge and 50% to 64% in the ascending aorta. Thus, there is a high prevalence of aortic root enlargement in patients with a bicuspid aortic valve that occurs irrespective of altered hemodynamics or age. These findings support the hypothesis that bicuspid aortic valve and aortic root dilation may reflect a common developmental defect.

Quantitative assessment of aortic regurgitation by combined two-dimensional, continuous-wave and colour flow Doppler measurements

The width of the regurgitant jet at the aortic valve plane, i.e. the core flow diameter, the ratio of the jet width to the left ventricular outflow diameter, the regurgitant volume and regurgitant fraction were determined using two-dimensional, continuous wave and colour flow Doppler echocardiography. The relationship between the non-invasive measurements and semiquantitative angiographic grading of the regurgitant flow (1 + to 4+) was examined in a primary group of 20 patients with chronic aortic regurgitation. Cut-off points for the non-invasive measurements were selected so as to separate patients with mild or moderate regurgitation (1+ or 2+) from patients with moderately severe or severe regurgitation (3+ or 4+). These cut-off points were prospectively applied in a new group of 35 patients with aortic regurgitation to predict the angiographic grading. Jet width correctly predicted the angiographic grading in 86% of cases, the ratio of the jet width to the outflow diameter in 83% of cases, the regurgitant volume in 86% of cases and the regurgitant fraction in 91% of cases. We conclude that the severity of aortic regurgitation as determined by angiographic grading can be estimated with reasonable accuracy by non-invasive techniques based on colour flow imaging.