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Mechanism and incidence of notched pulmonary venous atrial reversal wave
Mechanism and Incidence of Notched Pulmonary Venous Atrial Reversal Wave Dae-Won Sohn, MD, Rak-Kyeong Choi, MD, and Yong-Jin Kim, MD, Seoul, Korea
In certain patients, pulmonary venous flow pattern obtained by the pulsed wave Doppler during transesophageal echocardiography shows a notching on the atrial reversal (A) wave. However, the incidence or the mechanism of this notched A wave has not been described. After transthoracic echocardiographic evaluation for the chamber sizes, wall thickness, and left-ventricular function, transesophageal echocardiography was performed in 100 patients with in sinus rhythm. Discernible pulmonary venous A wave was observed in 46 patients. Among these 46 patients, notched A wave was observed in 11 (31%). In 4 patients with notched A wave, leftatrial pressure waveforms could be obtained during mitral balloon valvuloplasty. In all these patients, left-atrial pressure waveforms showed prominent c
P
ulmonary venous flow pattern can be obtained more reliably with transesophageal echocardiography (TEE) compared with transthoracic echocardiography (TTE). In our laboratory, pulmonary venous flow pattern has been routinely obtained during TEE and revealed, in certain patients, notched pulmonary venous atrial reversal (A) waves that are not clearly seen with TTE. To our knowledge, however, the mechanism or the incidence of this notched A wave has not been discussed.
waves. In 2 patients, transesophageal echocardiography was repeated after mitral balloon valvuloplasty. Late peak of the notched A wave decreased with the decrease in the magnitude of rise in leftatrial c wave. Among the transthoracic echocardiographic parameters, patients with notching (n ⴝ 11) had significantly larger left atriums than patients without notching (n ⴝ 35)(49.3 ⴞ 6.2 vs 37.3 ⴞ 4.4 mm, P < .0001). There were no significant differences in left-ventricular dimensions, wall thickness, and ejection fraction. In conclusion, notched pulmonary venous A wave indicates the presence of left-atrial c wave; and presence of left-atrial c wave may represent decreased left-atrial compliance. (J Am Soc Echocardiogr 2003;16:77-9.)
intramural hematoma (3), evaluation for valvular regurgitation (12), and uncertain cause of dyspnea (1). Echocardiography Echocardiograms were obtained using Acuson XP/10 (Mountain View, Calif) with a 2.5-MHz transducer. After TTE evaluation for chamber sizes, wall thickness, and left-ventricular function, TEE was performed according to the recommendation1 reported earlier. Pulmonary venous flow signal was obtained at the left upper pulmonary vein using pulsed wave Doppler and recorded on a strip chart with a sweep speed of 100 mm/s.
METHODS Statistics Study Subjects A total of 100 patients with in sinus rhythm who were referred to our laboratory for TEE were enrolled. Mean age was 52 ⫾ 12 years, and 74 patients were male (74%). Indications for the TEE were: evaluation of the intracardiac source of emboli (76), possible candidate for mitral balloon valvuloplasty (8), follow up examination for aortic From the Clinical Research Institute and Division of Cardiology, Department of Internal Medicine, Seoul National University College of Medicine. Reprint requests: Dae-Won Sohn, MD, Division of Cardiology, Department of Internal Medicine, Seoul National University College of Medicine, 28 Yungun-Dong, Chongno-Gu, Seoul 110744, Korea (E-mail: [email protected]). Copyright 2003 by the American Society of Echocardiography. 0894-7317/2003/$30.00 ⫹ 0 doi:10.1067/mje.2003.38
Results are reported as the mean values ⫾ SD. Student t test was used to compare TTE parameters in patients with and without notched A waves. A P value of less than .05 was considered statistically significant.
RESULTS A discernible pulmonary venous A wave was present in 46 patients and a notching on the A wave (Figure 1) was noticed in 11 (31%). Referral diagnosis of the patients with notched A wave were: mitral stenosis for the detection of left-atrial thrombus (5), cerebral infarction for the source of emboli (5), and dyspnea of uncertain cause (1). In 4 patients with notched A wave, left-atrial pressure waveforms could be obtained during mitral balloon valvuloplasty. Promi-
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Figure 1 Pulmonary venous flow obtained by transesophageal echocardiography in patients with mitral stenosis. Notching on pulmonary venous atrial reversal wave is noted. Figure 3 Before (A) and after (B) mitral balloon valvuloplasty in patients with notched pulmonary venous atrial reversal (A) wave. With decrease in left-atrial pressure, both late peak in pulmonary venous A wave and left-atrial c wave decreased. Table 1 Transthoracic echocardiographic parameters in patients with discernible pulmonary venous A wave
Figure 2 Right- (A) and left- (B) atrial pressures in patient shown in Figure 1. Prominent c wave is noted in left-atrial pressure. However, right-atrial pressure did not show c wave.
nent c waves were observed in the left-atrial pressure waveforms (Figure 2). In 2 patients, TEE was repeated after mitral balloon valvuloplasty and late peak of the notched A wave decreased with the decrease in the magnitude of rise in left-atrial c wave (Figure 3). Among the echocardiographic parameters in patients with discernible pulmonary venous A wave (n ⫽ 46), patients with notched A wave (n ⫽ 11) had significantly larger left atriums than those patients without notching (n ⫽ 35). There was no significant difference in left-ventricular dimensions, wall thickness, and ejection fraction (Table).
DISCUSSION The first peak of the notched pulmonary venous A wave is produced by the rise in left-atrial pressure as a result of left-atrial contraction; that is, a wave in left-atrial pressure. The second peak implies that there is an additional rise in the left-atrial pressure between the first peak and the systolic forward flow; that is, between a wave and x descent in left-atrial pressure. Therefore, the timing of the late peak coincides with c wave. Two findings in our study support this speculation. First, in 4 patients with notched A wave, prominent left-atrial c waves were
Left ventricular dimension (mm) systolic diastolic Left ventricular wall thickness (mm)* EF (%) Left atrial dimension (mm)
Notching (ⴚ) N ⴝ 35
Notching (ⴙ) N ⴝ 11
P value
32.2 ⫾ 6.3 50.0 ⫾ 606 10.9 ⫾ 1.7
33.5 ⫾ 6.3 51.7 ⫾ 5.6 11.0 ⫾ 2.2
NS NS NS
58.0 ⫾ 10.6 37.3 ⫾ 4.4
57.9 ⫾ 9.4 49.3 ⫾ 6.2
NS ⬍.005
*(interventricular septal thickness ⫹ left ventricular posterior wall thickness)/2; NS, not significant; EF, ejection fraction.
observed at the time of mitral balloon valvuloplasty. Second, TEE was repeated after mitral balloon valvuloplasty in 2 patients and the changes in left-atrial c waves were reflected in the changes of late peak of notched A waves. Two theories have been suggested as the mechanism of production of a jugular venous c wave. In one theory, the jugular venous c wave was presumed to have been caused by carotid-artery interference.2 However, later studies regarding the timing of the jugular venous c wave and carotid-artery pulsation did not support this theory.3-5 Therefore, another, more reasonable theory is that the jugular venous or right-atrial c wave is caused by the closure of the tricuspid valve. An opinion that combines the 2 theories6 (that both carotid-artery pulsation and tricuspid valve closure contribute to the production of jugular venous c wave) has also been suggested. Considering the similarity between the left- and right-atrial event in the production of atrial pressure
Journal of the American Society of Echocardiography Volume 16 Number 1
waves, left-atrial c wave is presumed to be caused by mitral valve closure. Among the TTE parameters, patients with notching on the pulmonary venous A wave had significantly larger left atriums than those patients without notching. It is conceivable that, because of the decreased left-atrial compliance in patients with an enlarged left atrium, the small volume change during mitral valve closure produces a significant pressure rise that can be manifested as c wave. This speculation is further favored by the decrease in the magnitude of rise in c wave with the decrease in left-atrial pressure and absence of c wave in the right-atrial pressure, despite the presence of a prominent left-atrial c wave seen in 4 patients who underwent mitral balloon valvuloplasty (Figure 2). Although atrial c wave is reported to be present in healthy patients, whether it is truly a normal finding was once questioned on the basis of the infrequency of c wave in right-atrial pressure tracings at cardiac catheterization laboratories. Presence of prominent
Sohn, Choi, Kim
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atrial c wave might represent “stiff atrium,” even if the patient can be categorized as normal on the basis of current diagnostic criteria. Therefore, more sophisticated study is needed to validate this speculation. REFERENCES 1. Seward JB, Khandheria BK, Oh JK, Abel MD, Hughes RW Jr, Edward WD, et al. Transesophageal echocardiography: technique, anatomic correlations, implementation, and clinical applications. Mayo Clin Proc 1988;63:649-80. 2. Meckenzie J. Disease of the heart. 2nd ed. New York: Oxford Medical Publications; 1910. p. 113. 3. Hartman H. The jugular venous tracing. Am Heart J 1960;59: 698-717. 4. Feder W, Cherry RA. External jugular phlebogram as reflecting venous and right atrial hemodynamics. Am J Cardiol 1963:12; 383-93. 5. Bonner AJ Jr, Tavel ME. The relationship of the jugular “C” wave to changing diastolic intervals. Am Heart J 1972;84: 441-5. 6. Colman AL. Jugular C wave. N Engl J Med 1971;285:462.
In certain patients, pulmonary venous flow pattern obtained by the pulsed wave Doppler during transesophageal echocardiography shows a notching on the atrial reversal (A) wave. However, the incidence or the mechanism of this notched A wave has not been described. After transthoracic echocardiographic evaluation for the chamber sizes, wall thickness, and left-ventricular function, transesophageal echocardiography was performed in 100 patients with in sinus rhythm. Discernible pulmonary venous A wave was observed in 46 patients. Among these 46 patients, notched A wave was observed in 11 (31%). In 4 patients with notched A wave, leftatrial pressure waveforms could be obtained during mitral balloon valvuloplasty. In all these patients, left-atrial pressure waveforms showed prominent c
P
ulmonary venous flow pattern can be obtained more reliably with transesophageal echocardiography (TEE) compared with transthoracic echocardiography (TTE). In our laboratory, pulmonary venous flow pattern has been routinely obtained during TEE and revealed, in certain patients, notched pulmonary venous atrial reversal (A) waves that are not clearly seen with TTE. To our knowledge, however, the mechanism or the incidence of this notched A wave has not been discussed.
waves. In 2 patients, transesophageal echocardiography was repeated after mitral balloon valvuloplasty. Late peak of the notched A wave decreased with the decrease in the magnitude of rise in leftatrial c wave. Among the transthoracic echocardiographic parameters, patients with notching (n ⴝ 11) had significantly larger left atriums than patients without notching (n ⴝ 35)(49.3 ⴞ 6.2 vs 37.3 ⴞ 4.4 mm, P < .0001). There were no significant differences in left-ventricular dimensions, wall thickness, and ejection fraction. In conclusion, notched pulmonary venous A wave indicates the presence of left-atrial c wave; and presence of left-atrial c wave may represent decreased left-atrial compliance. (J Am Soc Echocardiogr 2003;16:77-9.)
intramural hematoma (3), evaluation for valvular regurgitation (12), and uncertain cause of dyspnea (1). Echocardiography Echocardiograms were obtained using Acuson XP/10 (Mountain View, Calif) with a 2.5-MHz transducer. After TTE evaluation for chamber sizes, wall thickness, and left-ventricular function, TEE was performed according to the recommendation1 reported earlier. Pulmonary venous flow signal was obtained at the left upper pulmonary vein using pulsed wave Doppler and recorded on a strip chart with a sweep speed of 100 mm/s.
METHODS Statistics Study Subjects A total of 100 patients with in sinus rhythm who were referred to our laboratory for TEE were enrolled. Mean age was 52 ⫾ 12 years, and 74 patients were male (74%). Indications for the TEE were: evaluation of the intracardiac source of emboli (76), possible candidate for mitral balloon valvuloplasty (8), follow up examination for aortic From the Clinical Research Institute and Division of Cardiology, Department of Internal Medicine, Seoul National University College of Medicine. Reprint requests: Dae-Won Sohn, MD, Division of Cardiology, Department of Internal Medicine, Seoul National University College of Medicine, 28 Yungun-Dong, Chongno-Gu, Seoul 110744, Korea (E-mail: [email protected]). Copyright 2003 by the American Society of Echocardiography. 0894-7317/2003/$30.00 ⫹ 0 doi:10.1067/mje.2003.38
Results are reported as the mean values ⫾ SD. Student t test was used to compare TTE parameters in patients with and without notched A waves. A P value of less than .05 was considered statistically significant.
RESULTS A discernible pulmonary venous A wave was present in 46 patients and a notching on the A wave (Figure 1) was noticed in 11 (31%). Referral diagnosis of the patients with notched A wave were: mitral stenosis for the detection of left-atrial thrombus (5), cerebral infarction for the source of emboli (5), and dyspnea of uncertain cause (1). In 4 patients with notched A wave, left-atrial pressure waveforms could be obtained during mitral balloon valvuloplasty. Promi-
77
78 Sohn, Choi, Kim
Journal of the American Society of Echocardiography January 2003
Figure 1 Pulmonary venous flow obtained by transesophageal echocardiography in patients with mitral stenosis. Notching on pulmonary venous atrial reversal wave is noted. Figure 3 Before (A) and after (B) mitral balloon valvuloplasty in patients with notched pulmonary venous atrial reversal (A) wave. With decrease in left-atrial pressure, both late peak in pulmonary venous A wave and left-atrial c wave decreased. Table 1 Transthoracic echocardiographic parameters in patients with discernible pulmonary venous A wave
Figure 2 Right- (A) and left- (B) atrial pressures in patient shown in Figure 1. Prominent c wave is noted in left-atrial pressure. However, right-atrial pressure did not show c wave.
nent c waves were observed in the left-atrial pressure waveforms (Figure 2). In 2 patients, TEE was repeated after mitral balloon valvuloplasty and late peak of the notched A wave decreased with the decrease in the magnitude of rise in left-atrial c wave (Figure 3). Among the echocardiographic parameters in patients with discernible pulmonary venous A wave (n ⫽ 46), patients with notched A wave (n ⫽ 11) had significantly larger left atriums than those patients without notching (n ⫽ 35). There was no significant difference in left-ventricular dimensions, wall thickness, and ejection fraction (Table).
DISCUSSION The first peak of the notched pulmonary venous A wave is produced by the rise in left-atrial pressure as a result of left-atrial contraction; that is, a wave in left-atrial pressure. The second peak implies that there is an additional rise in the left-atrial pressure between the first peak and the systolic forward flow; that is, between a wave and x descent in left-atrial pressure. Therefore, the timing of the late peak coincides with c wave. Two findings in our study support this speculation. First, in 4 patients with notched A wave, prominent left-atrial c waves were
Left ventricular dimension (mm) systolic diastolic Left ventricular wall thickness (mm)* EF (%) Left atrial dimension (mm)
Notching (ⴚ) N ⴝ 35
Notching (ⴙ) N ⴝ 11
P value
32.2 ⫾ 6.3 50.0 ⫾ 606 10.9 ⫾ 1.7
33.5 ⫾ 6.3 51.7 ⫾ 5.6 11.0 ⫾ 2.2
NS NS NS
58.0 ⫾ 10.6 37.3 ⫾ 4.4
57.9 ⫾ 9.4 49.3 ⫾ 6.2
NS ⬍.005
*(interventricular septal thickness ⫹ left ventricular posterior wall thickness)/2; NS, not significant; EF, ejection fraction.
observed at the time of mitral balloon valvuloplasty. Second, TEE was repeated after mitral balloon valvuloplasty in 2 patients and the changes in left-atrial c waves were reflected in the changes of late peak of notched A waves. Two theories have been suggested as the mechanism of production of a jugular venous c wave. In one theory, the jugular venous c wave was presumed to have been caused by carotid-artery interference.2 However, later studies regarding the timing of the jugular venous c wave and carotid-artery pulsation did not support this theory.3-5 Therefore, another, more reasonable theory is that the jugular venous or right-atrial c wave is caused by the closure of the tricuspid valve. An opinion that combines the 2 theories6 (that both carotid-artery pulsation and tricuspid valve closure contribute to the production of jugular venous c wave) has also been suggested. Considering the similarity between the left- and right-atrial event in the production of atrial pressure
Journal of the American Society of Echocardiography Volume 16 Number 1
waves, left-atrial c wave is presumed to be caused by mitral valve closure. Among the TTE parameters, patients with notching on the pulmonary venous A wave had significantly larger left atriums than those patients without notching. It is conceivable that, because of the decreased left-atrial compliance in patients with an enlarged left atrium, the small volume change during mitral valve closure produces a significant pressure rise that can be manifested as c wave. This speculation is further favored by the decrease in the magnitude of rise in c wave with the decrease in left-atrial pressure and absence of c wave in the right-atrial pressure, despite the presence of a prominent left-atrial c wave seen in 4 patients who underwent mitral balloon valvuloplasty (Figure 2). Although atrial c wave is reported to be present in healthy patients, whether it is truly a normal finding was once questioned on the basis of the infrequency of c wave in right-atrial pressure tracings at cardiac catheterization laboratories. Presence of prominent
Sohn, Choi, Kim
79
atrial c wave might represent “stiff atrium,” even if the patient can be categorized as normal on the basis of current diagnostic criteria. Therefore, more sophisticated study is needed to validate this speculation. REFERENCES 1. Seward JB, Khandheria BK, Oh JK, Abel MD, Hughes RW Jr, Edward WD, et al. Transesophageal echocardiography: technique, anatomic correlations, implementation, and clinical applications. Mayo Clin Proc 1988;63:649-80. 2. Meckenzie J. Disease of the heart. 2nd ed. New York: Oxford Medical Publications; 1910. p. 113. 3. Hartman H. The jugular venous tracing. Am Heart J 1960;59: 698-717. 4. Feder W, Cherry RA. External jugular phlebogram as reflecting venous and right atrial hemodynamics. Am J Cardiol 1963:12; 383-93. 5. Bonner AJ Jr, Tavel ME. The relationship of the jugular “C” wave to changing diastolic intervals. Am Heart J 1972;84: 441-5. 6. Colman AL. Jugular C wave. N Engl J Med 1971;285:462.