- Email: [email protected]
Effect of Percutaneous Mitral Balloon Valvuloplasty on Left Atrial Appendage Function: A Doppler Tissue Study
Effect of Percutaneous Mitral Balloon Valvuloplasty on Left Atrial Appendage Function: A Doppler Tissue Study Osman Karakaya, MD, Muhsin Turkmen, MD, Atilla Bitigen, MD, Mustafa Saglam, MD, Irfan Barutcu, MD, Ali Metin Esen, MD, Mustafa Bulut, MD, Erdem Turkyilmaz, MD, and Cevat Kirma, MD, FESC, Istanbul, Turkey
The aim of this study was to compare left atrial appendage (LAA) functions by Doppler tissue imaging (DTI) before and after percutaneous balloon mitral valvuloplasty (PBMV). Twenty patients with symptomatic rheumatic mitral stenosis who underwent PBMV were included in this study. LAA functions were measured before and after PBMV. To determine LAA functions, LAA late filling (LAALF) velocity, LAA late emptying (LAALE) velocity, and area change of LAA percent were measured. In the DTI records, the first positive wave identical to the LAALE wave after the P wave was accepted as LAA late systolic wave, and the second negative wave identical to the LAALF flow was accepted as late diastolic wave. There was no difference in LAALF velocity and area change of LAA percent after PBMV. LAALE velocity increased after PBMV compared with baseline (P ⴝ .005). Late emptying, systolic, and
Reduced left atrial (LA) appendage (LAA) function
can be a cause for stroke in patients with in sinus rhythm even in the absence of mitral valve disease.1 A subset of mitral stenosis (MS) in sinus rhythm at increased risk of embolization can be indicated by a Doppler transesophageal echocardiographic (TEE) LAA flow profile.2 One of the factors implicated in the development of the thrombus is stasis in LA and LAA, observed as a reduction in blood flow velocity.3,4 Stasis in blood flow in a patient with chronic MS occurs concomitantly with reduction in wall movement. Both the magnitude and the pattern of LAA emptying and filling velocities are dependent on loading conditions, and LAA function is influenced to a greater extent by changes in left ventricular function.5 Doppler tissue imaging (DTI) is a new ultrasonographic technique based on the Doppler principle From the Department of Cardiology, Kosuyolu Heart Education and Research Hospital. Reprint requests: Irfan Barutcu, MD, 19 Mayıs Mahallesi Sarıkanarya Sok, Muhsinbey Apt No: 25/17-Kozyatagˇı, Istanbul, Turkey (E-mail: [email protected]). 0894-7317/$32.00 Copyright 2006 by the American Society of Echocardiography. doi:10.1016/j.echo.2005.10.022
434
diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline (P ⴝ .023, P ⴝ .002, and P ⴝ .002, respectively). LAALE velocity measured by standard Doppler was increased after PBMV compared with baseline (P ⴝ .005), but there was no change in area change of LAA percent or LAALF. Spontaneous echocontrast was present in 7 of the 20 patients before procedure. It completely disappeared (4 patients) or decreased (3 patients) after procedure. In patients with spontaneous echocontrast, LAALE and late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline. Our results suggest that PBMV improves LAA functions and, thereby, may have a favorable influence on future thromboembolic complications. (J Am Soc Echocardiogr 2006;19:434-437.)
that allows quantification of intramural myocardial velocities by detection of consecutive phase shift of the ultrasound signal reflected from contracting myocardium.6 LAA Doppler tissue velocities have been shown to decrease in patients with MS and normal in sinus rhythm.7,8 However, the changes in LAA functions of patients with MS after percutaneous balloon mitral valvuloplasty (PBMV) have not been studied yet. Therefore, the purpose of this study was to evaluate the effect of PBMV on LAA functions by DTI in patients with MS.
METHODS Study Group A total of 20 patients with rheumatic MS (4 men and 16 women; mean age 33 ⫾ 8 years) were included in the study. Those who were fulfilling the PBMV intervention criteria and those who had experienced a successful intervention were included.9 Patients who did not accept TEE evaluation after PBMV; who had hypertension, diabetes mellitus, congenital heart disease, atrial fibrillation, left ventricular systolic dysfunction, mitral prosthetic valve, aortic stenosis, or history of myocar-
Journal of the American Society of Echocardiography Volume 19 Number 4
Karakaya et al 435
dial infarction; or who underwent PBMV in an emergency condition were excluded from the study. All participants gave their informed consent and our institutional review board approved the study protocol.
was accepted as LAA late systolic wave, and the second negative wave identical to the LAA late filling (LAALF) flow was accepted as late diastolic wave.
Transthoracic Echocardiography
LAA maximal and minimal areas were calculated coincidentally with the P wave and QRS complex on ECG, respectively. Areas were measured by tracing a line from the top of the limbus of the upper left pulmonary vein along the whole appendage endocardial border. Area change of LAA (LAAAC) percent was calculated according to the formula: (maximal LAA area ⫺ minimal LAA area)/maximal LAA area ⫻ 100.
All participants underwent transthoracic echocardiography (TTE) and TEE evaluation by an experienced research echocardiographer using commercially available equipment with a 3.5-MHz transducer (Vivid System Five, GE Vingmed, Horten, Norway). TTE including 2-dimensional and Doppler echocardiographic studies were performed in the left lateral decubitus position with conventional views (parasternal long and short axis, apical 4 chambers) according to the American Society of Echocardiography guidelines.10 Mitral valve area was calculated both by direct planimetric method on short-axis view during diastole and by pressure half-time method.11 The mean and peak diastolic transmitral pressure gradients were determined from apical 4-chamber view. Parameters measured by TTE were measured again on the third day after PBMV. TEE After completion of TTE all patients were asked to refrain from oral water and food intake for at least 4 hours. Using a 5-MHz multiplane transesophageal probe, TEE was performed. Electrocardiographic (ECG) monitoring was performed and arterial saturation was followed by pulse oximetry during TEE examination. Topical lidocaine spray was used to anesthetize the oropharynx, and sedation with meperidine was achieved if needed. Throughout the study, a 1-lead ECG was recorded continuously. An appropriate position with peripheral venous line was also obtained before the procedure. The TEE probe was swallowed after adequate topical anesthesia and sedation. Routine TEE measurements were made completely. All images were recorded on a magneto-optical disk for subsequent analysis. The measurements were conducted using software (EchoPAC 6.4.1) (GE Vingmed Ultrasound, Horten, Norway). Doppler Tissue Examination of LAA LAA Doppler tissue records were obtained by the sample volume of pulsed wave (PW) Doppler placed on LAA lateral wall while imaging transverse basal shortaxis view. Sample volume was positioned within the walls of the LAA near the orifice to obtain spectral analysis of PW Doppler interrogation. The ultrasonic Doppler beam was aligned as parallel as possible to each myocardial wall. The adjustments necessary for DTI were done automatically using the software loaded on the equipment. Care was taken to keep the cursor as parallel as possible to the LAA wall, and to allow it to take myocardial records during the whole heart cycle. In the DTI records, the first positive wave identical to the LAA late emptying (LAALE) wave after the P wave
LAA Dimensions
LAA Doppler Flow LAA flow measurements were obtained from a side approximately 1 cm below the outlet of LAA cavity, where there were no wall artifacts and a net flow could be recorded by using PW Doppler, provided that suitable gain and filter adjustments were done. LAA emptying and filling velocities were also measured. In cases with quadriphasic wave patterns, the positive flow observed before the P wave on the ECG was referred to as early emptying velocity; the negative flow after early emptying velocity, as early filling velocity; the positive flow observed after P wave, as LAALF velocity; and the negative flow immediately after this velocity, as LAALE velocity. A mean 5 consecutive cycles was used to calculate all echocardiography parameters. All procedures including standard TTE, DTI, and TEE examinations were repeated on the third day after PBMV. The acquired images were also analyzed by one other cardiologist blinded to clinical detail to obtain the interobserver variability and also by the same cardiologist twice on different days to obtain the intraobserver variability. Interobserver and intraobserver variability was found to be less than 5% for both. Statistical Analysis Statistical analysis was performed with software (SPSS for Windows, Version 10.0, SPSS Inc, Chicago, Ill). Data are presented as mean ⫾ SD. Nonparametric continuous variables were tested with paired sample test. A P value less than .05 was considered to indicate statistical significance.
RESULTS All patients had rheumatic valve disease origin. All patients were in sinus rhythm. New York Heart Association functional capacity was class III in 13 patients and class II in 7 patients before PBMV. After PBMV, functional capacities were class I in 19 patients and class II in one patient. Comparison of pre- and post-PBMV measurements performed by TTE are shown in Table 1. Comparison of LAA functions before and after PBMV are illustrated in
Journal of the American Society of Echocardiography April 2006
436 Karakaya et al
Table 1 Comparison of transthoracic echocardiographic variables before and after percutaneous balloon mitral valvuloplasty Variables
Before
After
LA, cm 3.6 ⫾ 0.46 2.49 ⫾ 0.68 EF, % 58 ⫾ 8.3 63 ⫾ 6.9 LV diastolic diameter, cm 4.5 ⫾ 0.4 4.5 ⫾ 0.4 LV systolic diameter, cm 2.8 ⫾ 0.4 2.8 ⫾ 0.4 Max Gr, mm Hg 14 ⫾ 7.8 7⫾2 Mean Gr, mm Hg 8⫾5 3 ⫾ 1.3 MVA pht, cm2 0.7 ⫾ 0.2 1.9 ⫾ 0.27 MVA plan, cm2 1 ⫾ 0.2 2.2 ⫾ 0.2 PAP, mm Hg 66 ⫾ 8 41 ⫾ 9
P values
.002 NS NS NS .002 .0001 .0001 .0001 .0001
EF1, Left ventricular ejection fraction; LA, left atrial diameter; LV, left ventricular; Max Gr, mitral maximum gradient; Mean Gr, mitral mean gradient; MVA pht, pressure half-time mitral valve area; MVA plan, planimetric mitral valve area; NS, statistically not significant; PAP, pulmonary artery pressure.
Figure 1 Left atrial appendage Doppler tissue imaging velocities obtained in study patient.
Table 2 Comparison of left atrial appendage parameters measured by transesophageal echocardiography before and after percutaneous balloon mitral valvuloplasty Variables
LAALE, cm/s LAALF, cm/s LEW, cm/s LSW, cm/s LDW, cm/s LAAAC, %
Before
31 44 8 29 8.4 46
⫾ ⫾ ⫾ ⫾ ⫾ ⫾
16 18 4.6 3.4 3.4 8
After
P values
⫾ ⫾ ⫾ ⫾ ⫾ ⫾
.005 NS .023 .002 .002 NS
42 46 22 45 14 53
15 15 10 8.2 6.4 8
LAAAC%, left atrial appendage area change; LEW, late emptying wave; LSW, late systolic wave; LDW, late diastolic wave. LEW, late emptying wave; LSW, late diastolic wave; NS, statistically not significant.
Figure 2 Sample of left atrial appendage area measurement.
Table 2. There was no difference in LAALF velocity and LAAAC percent after PBMV. LAALE velocity increased after PBMV compared with baseline (P ⫽ .005). Late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline (P ⫽ .023, P ⫽ .002, and P ⫽ .002, respectively). Spontaneous echocontrast (SEC) was present in 7 of the 20 patients before procedure but completely disappeared (4 patients) or decreased (3 patients) after procedure. In patients with SEC, LAALE and late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline (23 ⫾ 12 vs 39 ⫾ 11 cm/s, P ⫽ .003; 7.6 ⫾ 3.3 vs 16.3 ⫾ 3.9 cm/s, P ⫽ .003; 25 ⫾ 2.9 vs 36 ⫾ 6.1 cm/s, P ⫽ .006; and 7.4 ⫾ 3.2 vs 12 ⫾ 3.9 cm/s, P ⫽ .002, respectively). However, the other parameters remained unaltered after PBMV. LAALE velocity measured by standard Doppler was increased after PBMV compared with baseline (P ⫽ .005), but there was no change in LAAAC percent or LAALF velocity. A representative illustration of DTI is shown in Figures 1 and 2.
DISCUSSION In this study we have noted that LAA functions are improved after PBMV as detected by DTI, and LAA emptying velocity measured by standard Doppler increased, but LAAAC percent and filling velocities did not alter after PBMV in patients with MS. Successful PBMV decreases the intensity of spontaneous LA contrast, reduces the size of the LA, and improves LA function. Even if these findings do not constitute proof for the efficacy of PBMV on thromboembolism or even more so on atrial fibrillation, they consistently show the beneficial effect of the procedure on the causes of these conditions.12,13 Effect of PBMV on LAA functions has been investigated in various studies. Wang et al14 showed the changes in LAA flow velocities and in SEC at the time of transient occlusion of mitral valve by balloon inflation.14 LAA blood flow velocity reduces substantially even to the point of complete stasis resulting in
Journal of the American Society of Echocardiography Volume 19 Number 4
acute enhancement of SEC to the highest grade almost simultaneously during the mechanical obstruction of blood flow by balloon inflation at the mitral valve. Upon balloon deflation, LAA blood flow velocity increases again resulting in the reduction or disappearance of SEC within the same time interval and LAA emptying and filling velocities have increased after procedure.14 Basal and postprocedure LAA velocities in patients with atrial fibrillation were found to be lower when compared with velocities in those with in sinus rhythm.14 In the same study at peak balloon inflation, LAA velocities were significantly lower and SEC was significantly higher in a group with atrial fibrillation than in a group with in sinus rhythm. Thus, the authors have concluded that regular contraction in sinus rhythm may decrease SEC formation. Relief of MS may not only confer hemodynamic benefits for improvement of symptoms but also have a favorable influence on future thromboembolism.15 It has been detected that LAA ejection fractions measured by planimetry do not increase but LAA peak Doppler velocities and integral of LAA velocities measured 48 hours after PBMV increases apparently.16 In another study the ratio of LAA emptying velocity to LA diameter was found to be superior to only velocity measurements for evaluation of LAA functions.17 In our study we found that LAA emptying velocity increased significantly. We also observed that planimetrically measured change in LAA area and filling velocities did not change. DTI is a relatively new ultrasound technique for use in quantifying regional myocardial function. With either pulsed or color format, it can be used to quantify inplane regional myocardial velocities.18 After showing the use of DTI in evaluating the LAA functions, its change in pathologic conditions has also been searched.7,8 Gurlertop et al8 determined that the PW Doppler tissue peak velocities in mitral valve diseases were decreased. However, the changes in LAA functions of patients with MS after PBMV have not been studied yet. Therefore, in this study, we evaluate the changes in LAA functions by DTI in patients with MS after PBMV. Our results suggest that PBMV improves LAA functions and, thereby, may have a favorable influence on future thromboembolic complications. However, these findings should be confirmed by further large-scale studies and long-term follow-up.
REFERENCES 1. Kamalesh M, Copeland TB, Sawada S. Severely reduced left atrial appendage function: a cause of embolic stroke in patients in sinus rhythm? J Am Soc Echocardiogr 1998;11:902-4.
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2. Daimee MA, Salama AL, Cherian G, Hayat NJ, Sugathan TN. Left atrial appendage function in mitral stenosis: is a group in sinus rhythm at risk of thromboembolism? Int J Cardiol 1998;66:45-54. 3. Shively BK, Gelgand EA, Crawfort MH. Regional left atrial stasis during atrial fibrillation and flutter: determinants and relation to stroke. J Am Coll Cardiol 1996;27:1722-9. 4. Goldman ME, Pearce LA, Hart RG, Zabalgoitia M, Asinger RW, Safford R, et al. Pathophysiologic correlates of thromboembolism in nonvalvular atrial fibrillation, I: reduced flow velocity in the left atrial appendage (the stroke prevention in atrial fibrillation [SPAFF-III] study). J Am Soc Echocardiogr 1999;12:1080-7. 5. Hoit BD, Shao Y, Gabel M. Influence of acutely altered loading conditions on left atrial appendage flow velocities. J Am Coll Cardiol 1994;24:1117-23. 6. McDicken WN, Sutherland GR, Moran CM, Gordon LN. Color Doppler velocity imaging of the myocardium. Ultrasound Med Biol 1992;18:651-4. 7. Topsakal R, Eryol NK, Ozdogru I, Seyfeli E, Abaci A, Oguzhan A, et al. Color Doppler tissue imaging to evaluate left atrial appendage function in patients with mitral stenosis in sinus rhythm. Echocardiography 2004;21:235-40. 8. Gurlertop Y, Yılmaz M, Acikel M, Bozkurt E, Erol MK, Senocak H, et al. Tissue Doppler properties of the left atrial appendage in patients with mitral valve disease. Echocardiography 2004;21:319-24. 9. Prendergast BD, Shaw TR, Iung B, Vahanian A, Northridge DB. Contemporary criteria for the selection of patients for percutaneous balloon mitral valvuloplasty. Heart 2002;87: 401-4. 10. Henry WL, DeMaria A, Gramiak R, King DL, Kisslo JA, Popp RL, et al. Report of the American Society of Echocardiography committee on nomenclature and standards in two-dimensional echocardiography. Circulation 1980;62:212-7. 11. Hatle L, Brubakk A, Tromsdal A, Angelsen B. Noninvasive assessment of pressure drop in mitral stenosis by Doppler ultrasound. Br Heart J 1978;40:131-40. 12. Vahanian A, Palacios IF. Percutaneous approaches to valvular disease. Circulation 2004;109:1572-9. 13. Chiang CW, Lo SK, Ko YS, Cheng NJ, Lin PJ, Chang CH. Predictors of systemic embolism in patients with mitral stenosis: a prospective study. Ann Intern Med 1998;128:885-9. 14. Wang J, Chung Ann Choo D, Zhang X, Yang Q, Xian T, Lu D, et al. The effect of transient balloon occlusion of the mitral valve on left atrial appendage blood flow velocity and spontaneous echo contrast. Clin Cardiol 2000;23:501-6. 15. Lin JM, Hsu KL, Hwang JJ, Li YH, Tseng YZ. Effects of percutaneous mitral valvuloplasty on left atrial appendage flow velocity. Am J Cardiol 1995;76:609-11. 16. Porte JM, Cormier B, Iung B, Dadez E, Starkman C, Nallet O, et al. Early assessment by transesophageal echocardiography of left atrial appendage function after percutaneous mitral commissurotomy. Am J Cardiol 1996;77:72-6. 17. Roijer A, Meurling CJ, Eskilsson J, Olsson B. Left atrial appendage outflow velocity index is superior to conventional criteria for prediction of maintenance of sinus rhythm after cardioversion: an echocardiographic study in patients with atrial fibrillation of a few months’ duration. Scand Cardiovasc J 2001;35:119-24. 18. Hatle L, Sutherland GR. Regional myocardial function–a new approach. Eur Heart J 2000;21:1337-57.
The aim of this study was to compare left atrial appendage (LAA) functions by Doppler tissue imaging (DTI) before and after percutaneous balloon mitral valvuloplasty (PBMV). Twenty patients with symptomatic rheumatic mitral stenosis who underwent PBMV were included in this study. LAA functions were measured before and after PBMV. To determine LAA functions, LAA late filling (LAALF) velocity, LAA late emptying (LAALE) velocity, and area change of LAA percent were measured. In the DTI records, the first positive wave identical to the LAALE wave after the P wave was accepted as LAA late systolic wave, and the second negative wave identical to the LAALF flow was accepted as late diastolic wave. There was no difference in LAALF velocity and area change of LAA percent after PBMV. LAALE velocity increased after PBMV compared with baseline (P ⴝ .005). Late emptying, systolic, and
Reduced left atrial (LA) appendage (LAA) function
can be a cause for stroke in patients with in sinus rhythm even in the absence of mitral valve disease.1 A subset of mitral stenosis (MS) in sinus rhythm at increased risk of embolization can be indicated by a Doppler transesophageal echocardiographic (TEE) LAA flow profile.2 One of the factors implicated in the development of the thrombus is stasis in LA and LAA, observed as a reduction in blood flow velocity.3,4 Stasis in blood flow in a patient with chronic MS occurs concomitantly with reduction in wall movement. Both the magnitude and the pattern of LAA emptying and filling velocities are dependent on loading conditions, and LAA function is influenced to a greater extent by changes in left ventricular function.5 Doppler tissue imaging (DTI) is a new ultrasonographic technique based on the Doppler principle From the Department of Cardiology, Kosuyolu Heart Education and Research Hospital. Reprint requests: Irfan Barutcu, MD, 19 Mayıs Mahallesi Sarıkanarya Sok, Muhsinbey Apt No: 25/17-Kozyatagˇı, Istanbul, Turkey (E-mail: [email protected]). 0894-7317/$32.00 Copyright 2006 by the American Society of Echocardiography. doi:10.1016/j.echo.2005.10.022
434
diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline (P ⴝ .023, P ⴝ .002, and P ⴝ .002, respectively). LAALE velocity measured by standard Doppler was increased after PBMV compared with baseline (P ⴝ .005), but there was no change in area change of LAA percent or LAALF. Spontaneous echocontrast was present in 7 of the 20 patients before procedure. It completely disappeared (4 patients) or decreased (3 patients) after procedure. In patients with spontaneous echocontrast, LAALE and late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline. Our results suggest that PBMV improves LAA functions and, thereby, may have a favorable influence on future thromboembolic complications. (J Am Soc Echocardiogr 2006;19:434-437.)
that allows quantification of intramural myocardial velocities by detection of consecutive phase shift of the ultrasound signal reflected from contracting myocardium.6 LAA Doppler tissue velocities have been shown to decrease in patients with MS and normal in sinus rhythm.7,8 However, the changes in LAA functions of patients with MS after percutaneous balloon mitral valvuloplasty (PBMV) have not been studied yet. Therefore, the purpose of this study was to evaluate the effect of PBMV on LAA functions by DTI in patients with MS.
METHODS Study Group A total of 20 patients with rheumatic MS (4 men and 16 women; mean age 33 ⫾ 8 years) were included in the study. Those who were fulfilling the PBMV intervention criteria and those who had experienced a successful intervention were included.9 Patients who did not accept TEE evaluation after PBMV; who had hypertension, diabetes mellitus, congenital heart disease, atrial fibrillation, left ventricular systolic dysfunction, mitral prosthetic valve, aortic stenosis, or history of myocar-
Journal of the American Society of Echocardiography Volume 19 Number 4
Karakaya et al 435
dial infarction; or who underwent PBMV in an emergency condition were excluded from the study. All participants gave their informed consent and our institutional review board approved the study protocol.
was accepted as LAA late systolic wave, and the second negative wave identical to the LAA late filling (LAALF) flow was accepted as late diastolic wave.
Transthoracic Echocardiography
LAA maximal and minimal areas were calculated coincidentally with the P wave and QRS complex on ECG, respectively. Areas were measured by tracing a line from the top of the limbus of the upper left pulmonary vein along the whole appendage endocardial border. Area change of LAA (LAAAC) percent was calculated according to the formula: (maximal LAA area ⫺ minimal LAA area)/maximal LAA area ⫻ 100.
All participants underwent transthoracic echocardiography (TTE) and TEE evaluation by an experienced research echocardiographer using commercially available equipment with a 3.5-MHz transducer (Vivid System Five, GE Vingmed, Horten, Norway). TTE including 2-dimensional and Doppler echocardiographic studies were performed in the left lateral decubitus position with conventional views (parasternal long and short axis, apical 4 chambers) according to the American Society of Echocardiography guidelines.10 Mitral valve area was calculated both by direct planimetric method on short-axis view during diastole and by pressure half-time method.11 The mean and peak diastolic transmitral pressure gradients were determined from apical 4-chamber view. Parameters measured by TTE were measured again on the third day after PBMV. TEE After completion of TTE all patients were asked to refrain from oral water and food intake for at least 4 hours. Using a 5-MHz multiplane transesophageal probe, TEE was performed. Electrocardiographic (ECG) monitoring was performed and arterial saturation was followed by pulse oximetry during TEE examination. Topical lidocaine spray was used to anesthetize the oropharynx, and sedation with meperidine was achieved if needed. Throughout the study, a 1-lead ECG was recorded continuously. An appropriate position with peripheral venous line was also obtained before the procedure. The TEE probe was swallowed after adequate topical anesthesia and sedation. Routine TEE measurements were made completely. All images were recorded on a magneto-optical disk for subsequent analysis. The measurements were conducted using software (EchoPAC 6.4.1) (GE Vingmed Ultrasound, Horten, Norway). Doppler Tissue Examination of LAA LAA Doppler tissue records were obtained by the sample volume of pulsed wave (PW) Doppler placed on LAA lateral wall while imaging transverse basal shortaxis view. Sample volume was positioned within the walls of the LAA near the orifice to obtain spectral analysis of PW Doppler interrogation. The ultrasonic Doppler beam was aligned as parallel as possible to each myocardial wall. The adjustments necessary for DTI were done automatically using the software loaded on the equipment. Care was taken to keep the cursor as parallel as possible to the LAA wall, and to allow it to take myocardial records during the whole heart cycle. In the DTI records, the first positive wave identical to the LAA late emptying (LAALE) wave after the P wave
LAA Dimensions
LAA Doppler Flow LAA flow measurements were obtained from a side approximately 1 cm below the outlet of LAA cavity, where there were no wall artifacts and a net flow could be recorded by using PW Doppler, provided that suitable gain and filter adjustments were done. LAA emptying and filling velocities were also measured. In cases with quadriphasic wave patterns, the positive flow observed before the P wave on the ECG was referred to as early emptying velocity; the negative flow after early emptying velocity, as early filling velocity; the positive flow observed after P wave, as LAALF velocity; and the negative flow immediately after this velocity, as LAALE velocity. A mean 5 consecutive cycles was used to calculate all echocardiography parameters. All procedures including standard TTE, DTI, and TEE examinations were repeated on the third day after PBMV. The acquired images were also analyzed by one other cardiologist blinded to clinical detail to obtain the interobserver variability and also by the same cardiologist twice on different days to obtain the intraobserver variability. Interobserver and intraobserver variability was found to be less than 5% for both. Statistical Analysis Statistical analysis was performed with software (SPSS for Windows, Version 10.0, SPSS Inc, Chicago, Ill). Data are presented as mean ⫾ SD. Nonparametric continuous variables were tested with paired sample test. A P value less than .05 was considered to indicate statistical significance.
RESULTS All patients had rheumatic valve disease origin. All patients were in sinus rhythm. New York Heart Association functional capacity was class III in 13 patients and class II in 7 patients before PBMV. After PBMV, functional capacities were class I in 19 patients and class II in one patient. Comparison of pre- and post-PBMV measurements performed by TTE are shown in Table 1. Comparison of LAA functions before and after PBMV are illustrated in
Journal of the American Society of Echocardiography April 2006
436 Karakaya et al
Table 1 Comparison of transthoracic echocardiographic variables before and after percutaneous balloon mitral valvuloplasty Variables
Before
After
LA, cm 3.6 ⫾ 0.46 2.49 ⫾ 0.68 EF, % 58 ⫾ 8.3 63 ⫾ 6.9 LV diastolic diameter, cm 4.5 ⫾ 0.4 4.5 ⫾ 0.4 LV systolic diameter, cm 2.8 ⫾ 0.4 2.8 ⫾ 0.4 Max Gr, mm Hg 14 ⫾ 7.8 7⫾2 Mean Gr, mm Hg 8⫾5 3 ⫾ 1.3 MVA pht, cm2 0.7 ⫾ 0.2 1.9 ⫾ 0.27 MVA plan, cm2 1 ⫾ 0.2 2.2 ⫾ 0.2 PAP, mm Hg 66 ⫾ 8 41 ⫾ 9
P values
.002 NS NS NS .002 .0001 .0001 .0001 .0001
EF1, Left ventricular ejection fraction; LA, left atrial diameter; LV, left ventricular; Max Gr, mitral maximum gradient; Mean Gr, mitral mean gradient; MVA pht, pressure half-time mitral valve area; MVA plan, planimetric mitral valve area; NS, statistically not significant; PAP, pulmonary artery pressure.
Figure 1 Left atrial appendage Doppler tissue imaging velocities obtained in study patient.
Table 2 Comparison of left atrial appendage parameters measured by transesophageal echocardiography before and after percutaneous balloon mitral valvuloplasty Variables
LAALE, cm/s LAALF, cm/s LEW, cm/s LSW, cm/s LDW, cm/s LAAAC, %
Before
31 44 8 29 8.4 46
⫾ ⫾ ⫾ ⫾ ⫾ ⫾
16 18 4.6 3.4 3.4 8
After
P values
⫾ ⫾ ⫾ ⫾ ⫾ ⫾
.005 NS .023 .002 .002 NS
42 46 22 45 14 53
15 15 10 8.2 6.4 8
LAAAC%, left atrial appendage area change; LEW, late emptying wave; LSW, late systolic wave; LDW, late diastolic wave. LEW, late emptying wave; LSW, late diastolic wave; NS, statistically not significant.
Figure 2 Sample of left atrial appendage area measurement.
Table 2. There was no difference in LAALF velocity and LAAAC percent after PBMV. LAALE velocity increased after PBMV compared with baseline (P ⫽ .005). Late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline (P ⫽ .023, P ⫽ .002, and P ⫽ .002, respectively). Spontaneous echocontrast (SEC) was present in 7 of the 20 patients before procedure but completely disappeared (4 patients) or decreased (3 patients) after procedure. In patients with SEC, LAALE and late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline (23 ⫾ 12 vs 39 ⫾ 11 cm/s, P ⫽ .003; 7.6 ⫾ 3.3 vs 16.3 ⫾ 3.9 cm/s, P ⫽ .003; 25 ⫾ 2.9 vs 36 ⫾ 6.1 cm/s, P ⫽ .006; and 7.4 ⫾ 3.2 vs 12 ⫾ 3.9 cm/s, P ⫽ .002, respectively). However, the other parameters remained unaltered after PBMV. LAALE velocity measured by standard Doppler was increased after PBMV compared with baseline (P ⫽ .005), but there was no change in LAAAC percent or LAALF velocity. A representative illustration of DTI is shown in Figures 1 and 2.
DISCUSSION In this study we have noted that LAA functions are improved after PBMV as detected by DTI, and LAA emptying velocity measured by standard Doppler increased, but LAAAC percent and filling velocities did not alter after PBMV in patients with MS. Successful PBMV decreases the intensity of spontaneous LA contrast, reduces the size of the LA, and improves LA function. Even if these findings do not constitute proof for the efficacy of PBMV on thromboembolism or even more so on atrial fibrillation, they consistently show the beneficial effect of the procedure on the causes of these conditions.12,13 Effect of PBMV on LAA functions has been investigated in various studies. Wang et al14 showed the changes in LAA flow velocities and in SEC at the time of transient occlusion of mitral valve by balloon inflation.14 LAA blood flow velocity reduces substantially even to the point of complete stasis resulting in
Journal of the American Society of Echocardiography Volume 19 Number 4
acute enhancement of SEC to the highest grade almost simultaneously during the mechanical obstruction of blood flow by balloon inflation at the mitral valve. Upon balloon deflation, LAA blood flow velocity increases again resulting in the reduction or disappearance of SEC within the same time interval and LAA emptying and filling velocities have increased after procedure.14 Basal and postprocedure LAA velocities in patients with atrial fibrillation were found to be lower when compared with velocities in those with in sinus rhythm.14 In the same study at peak balloon inflation, LAA velocities were significantly lower and SEC was significantly higher in a group with atrial fibrillation than in a group with in sinus rhythm. Thus, the authors have concluded that regular contraction in sinus rhythm may decrease SEC formation. Relief of MS may not only confer hemodynamic benefits for improvement of symptoms but also have a favorable influence on future thromboembolism.15 It has been detected that LAA ejection fractions measured by planimetry do not increase but LAA peak Doppler velocities and integral of LAA velocities measured 48 hours after PBMV increases apparently.16 In another study the ratio of LAA emptying velocity to LA diameter was found to be superior to only velocity measurements for evaluation of LAA functions.17 In our study we found that LAA emptying velocity increased significantly. We also observed that planimetrically measured change in LAA area and filling velocities did not change. DTI is a relatively new ultrasound technique for use in quantifying regional myocardial function. With either pulsed or color format, it can be used to quantify inplane regional myocardial velocities.18 After showing the use of DTI in evaluating the LAA functions, its change in pathologic conditions has also been searched.7,8 Gurlertop et al8 determined that the PW Doppler tissue peak velocities in mitral valve diseases were decreased. However, the changes in LAA functions of patients with MS after PBMV have not been studied yet. Therefore, in this study, we evaluate the changes in LAA functions by DTI in patients with MS after PBMV. Our results suggest that PBMV improves LAA functions and, thereby, may have a favorable influence on future thromboembolic complications. However, these findings should be confirmed by further large-scale studies and long-term follow-up.
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