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Iatrogenic Lutembacher's syndrome after percutaneous transluminal mitral valvotomy
Volume 119
Brief Communications
Number 1
with a " y " descent equal or deeper than the "x" descent was present in 78.9% in group A and in 31.6% in group B (p < 0.00001). T h e results of the present study demonstrate t h a t VF or ventricular tachycardia requiring emergency countershock m a y occur in 0.85% of the patients s u b m i t t e d to hemodynamic monitoring and is an almost exclusive finding in patients with AMI, and more precisely with inferior A M I (Fig. 1). F u r t h e r m o r e , the presence of E C G findings of acute RVI, such as Q wave and S T segment elevation in right precordial lead V4R o r a noncompliant p a t t e r n in the right atrial pressure waveform permits the identification of a high-risk group of patients for this complication. Interestingly, the aforementioned criteria m a y be easily identified prior to the insertion of the catheter and a selection of patients can be made or extreme precautions can be taken. VF has also been related to manipulation of pacing electrodes in patients with acute right ventricular necrosis. 13 Sclarovsky et al. 13 reported the occurrence of VF in 5 of 30 patients with A M I who underwent ventricular pacing, and all five had right ventricular infarction. Ventricular fibrillation appeared in four cases when pacing was started and in one case during the i m p l a n t a t i o n of the catheter. The a r r h y t h m i a was repetitive in two cases secondary to electrical stimulation. Thus it seems t h a t there is a relation between right ventricular mechanical stimulation and VF when there is acute right ventricular necrosis. It seems reasonable to recommend t h a t in patients with suspected RVI, indications for hemodynamic monitoring should be reconsidered on an individual basis, and a fullyt r a i n e d cardiologist should perform the insertion of the catheter in the appropriate setting. No d a t a are available concerning the possible benefit of prophylactic use of ant i a r r h y t h m i c drugs in these patients. 7 When an episode of V F occurs during insertion of a catheter, a new a t t e m p t to correctly place the catheter into the pulmonary artery m a y be successful in most cases, b u t the possibilities of producing a new episode of VF is extremely high (5 of 23 patients, 21.7 %), and hemodynamic monitoring should be reserved for patients in whom the clinical m a n a g e m e n t otherwise would be considered very difficult. REFERENCES
1. Cairns JA. Ventricular fibrillation due to passage of a SwanGanz catheter. Am J Cardiol 1975;35:589. 2. Katz JD, Cronau LH, Barash PG, Mandel SD. Pulmonary artery flow-guided catheters in the perioperative period. JAMA 1977;237:2832-4. 3. Elliot CG, Zimmerman GA, Clemmer TP. Complications of pulmonary artery catheterization in the care of critically ill patients. A prospective study. Chest 1979;76:647-52. 4. Sprung CL, Jacobs LJ, Caralis PV, Karpf M. Ventricular arrhythmia during Swan-Ganz catheterization of the critically ill. Chest 1981;79:413-15. 5. Sise MJ, Hollingsworth P, Brimm JE, Peters RM, Virgilio RW, Shackford SR. Complications of the flow-directed pulmonary-artery catheter: a prospective analysis in 219 patients. Crit Care Med 1981;9:315-18. 6. Sprung C1, Pozen RG, Rozanski JJ, Pinero LR, Eisler BR, Castellanos A. Advanced ventricular arrhythmias during bedside pulmonary artery catheterization. Am J Med 1982;72: 203-8. 7. Salmenpera M, Peltola K, Rosenberg P. Does prophylactic lidocaine control cardiac arrhythmias associated with pulmonary artery catheterization? Anesthesiology 1982;56:210-12.
209
8. Dee Boyd K, Thomas SJ, Gold J, Boyd AD. A prospective study of complications of pulmonary artery catheterizations in 500 consecutive patients. Chest 1983;84:245-9. 9. Shah KB, Rao TL, Laughlin S, E1-Etr AA. A review of pulmonary artery catheterization in 6,245 patients. Anesthesiology 1984;61:271-5. 10. Blanco Paj6n MJ, Fernandez de la Reguera G, Hurtado Reyes IC, Molina M~ndez FJ, Blackaller Palacios R, Luna Ortiz P. Complicaciones del uso del cat~ter de flotaci6n en cirugia cardiovascular. Estudio prospectivo. Arch Inst Cardiol Mex 1986;56:147-55. 11. L6pez-Send6n J, Coma-Canella I, Alcasena S, Seoane J, Gamallo C. Electrocardiographic findings in acute right ventricular infarction: sensitivity and specificity of electrocardiographic alterations in right precordial leads V4R, V3R, V1, V2 and V3. J Am Coll Cardiol 1985;6:1273-9. 12. L6pez-Send6n J, Coma-Canella I, Gamallo C. Sensitivity and specificity of hemodynamic criteria in the diagnosis of acute right ventricular infarction. Circulation 1981;64:515-25. 13. Sclarovsky S, Zafrir Z, Strasberg B, Krakoff O, Lewin R, Arditi A, Rosen KM, Agmon J. Ventricular fibrillation complicating temporary ventricular pacing in acute myocardial infarction: significance of right ventricular infarction. Am J Cardiol 1981;14:101-3.
latrogenic Lutembacher's syndrome after percutaneous transluminal mitral valvotomy Chen-Huan Chen, MD, Shoa-Lin Lin, MD, Tsui-Lieh Hsu, MD, Chin-Chien Chen, MD, Shih-Pu Wang, MD, and Mau-Song Chang, MD. Taipei, Taiwan, Republic of
China
Lutembacher's syndrome, indicating coexistence of atrial septal defect (ASD) and rheumatic mitral valve disease, is a recognized pathologic e n t i t y J Whereas a nonrestrictive atrial septal defect can decompress the left atrium and attenuate the pulmonary venous congestion, the mitral valvular lesion may augment the left-to-right interatrial shunt and precipitate right-sided h e a r t failure. The following case illustrates the interesting hemodynamic interaction although the ASD had been " c r e a t e d " during the procedure of percutaneous transluminal mitral valvotomy (PTMV). A 35-year-old woman had experienced palpitation and exertional dyspnea for more t h a n 15 years and rheumatic mitral stenosis had been diagnosed by cardiac catheterization for 8 years. She was referred for PTMV. Clinical examination revealed a grade IV/VI diastolic rumbling murmur with opening snap at the apex. The electrocardiogram showed atrial fibrillation and right ventricular hypertrophy. T h e chest x-ray film showed cardiomegaly with pulmonary congestion. The two-dimensionaI echocardiogram (2-D echo) demonstrated typical rheumatic mitral stenosis (Fig. 1, A). Pulsed Doppler echocardiography From the Divisionof Cardiology,Department of Medicine,Veterans General Hospital-Taipei, and National Yang-Ming Medical College. Reprint requests:Dr. Mau-SongChang,Divisionof Cardiology,Department of Medicine,Veterans General Hospital-Taipei, Taipei, Taiwan, Republic of China. 4/4/16524
2 10
January 1990 American Heart Journal
Brief Communications
T a b l e I. Hemodynamic data before, immediately after, and 3 months after percutaneous transluminal mitral valvotomy
Heart rate (beats/min) Right atrium (ram Hg) Right ventricle (ram Hg) Pulmonary artery (ram Hg) Left atrium (ram Hg) Left ventricle (mm Hg) Aortic pressure (ram Hg) Mean pressure gradient (ram Hg) Mitral valve area (cm2) Cardiac output (L/min) Pulmonary-tosystemic flow ratio Shunt flow (L/rain)
Fig. 1. Short-axis views of the diastolic mitral valve ori-
fice before (A), immediately after (B), and 3 months after valvuloplasty (C). The successful splitting of the posterior commissure (arrow) resulted in significant increase in mitral valve area. No evidence of fusion of the commissure was noted 3 months later.
demonstrated trivial mitral regurgitation and moderate tricuspid regurgitation. PTMV was performed with double balloon technique. 2 Before the procedure, no interatrial shunt could be demonstrated by oximetry. Immediately after the procedure, a left-to-right atrial shunt was detected. 2-D echo performed 24 hours after the PTMV
Before
After
3 Months
60
84
100
7
10
15
57/6
70/10
43/9
61/30
75/32
51/24
29
17
16
120/13
106/8
133/11
119/70
96/68
120/98
18
8
10
0.4
1.2
0.7
2.3
4.8
3.0
1.0
1.83
3.24
0
2.2
5.7
demonstrated split posterior commissure and increased mitral orifice (Fig. 1, B). Mild mitral regurgitation and moderate tricuspid regurgitation were demonstrated by color-coded Doppler echocardiography. The patient was discharged with improved exercise tolerance. Three months after PTMV, progressive abdominal fullness, lower leg edema, and shortness of breath developed. The jugular veins were bouncing. A grade III/VI systolic murmur could be heard at both the pulmonic area and left lower sternal border. The liver was enlarged and pulsatile. Shifting dullness could be demonstrated. Moderate peripheral edema was present. 2-D echo showed well-preserved splitting of the posterior commissure without significant reduction in valvular area (Fig. 1, C). The right atrium was enlarged. Color Doppler echocardiography disclosed moderate to severe mitral regurgitation, severe tricuspid regurgitation, and a turbulent flow passing from the left atrium to the right atrium through a defect at the interatrial septum (Fig. 2). Follow-up left and right heart catheterization (Table I) suggested restenosis of the mitral orifice and the presence of a large left-to-right atrial shunt. She subsequently underwent open-heart surgery for repair of the ASD, replacement of a prosthetic mitral valve, and tricuspid annuloplasty. During the operation, a linear defect 1 cm in length at the muscular atrial septum beneath the fossa ovalis was found. The posterior commissure was split well to the mitral anulus without evidence of restenosis. The mitral anterior leaflet was redundant with prominent regurgitant capacity. The patient was subsequently discharged after an uneventful recovery.
Volume 119
Brie[ Communications
Number 1
211
Fig. 2. C•••r•••dedD•pp•erech•cardi•gramd•ne3m•nthsaftervalvu••p•astydem•nstratedaturbu•ent flow (arrowhead) passing from the left atrium (LA) to the right atrium (RA) and right ventricle (RV) through a defect at the interatrial septum.
Creation of a significant ASD secondary to the transseptal technique is perhaps the most frequent complication of PTMV. Whereas the incidence of interatrial left-to-right shunt determined by oximetry immediately after PTMV is around 15% to 20% in larger series 3, 4 and may be as high as 57 % by transesophageal color Doppler technique, 5 the short-term and long-term follow-up results are still limited.6, 7 Palacios et al. 7 suggested that ASD is hemodynamically well tolerated and that two thirds of them are closed at follow-up, which was certainly not true in our case. The magnitude of interatrial left-to-right shunt may be increased by coexisting mitral valve lesions. In the setting of PTMV, the persistent mitral inflow obstruction (either due to initial unsuccessful PTMV or to later restenosis), the prexisting or created significant mitral regurgitation, and inadvertent transseptal puncture over the muscular portion of the atrial septum may prevent the healing of ASD. Our case clearly demonstrated that the presence of hemodynamically significant ASD could result in deterioration of the clinically silent right-sided heart overload in patients with rheumatic mitral stenosis and mandate an imminent surgical repair and valvular replacement, which obviously canceled the beneficial effect of PTMV. Thus it is essential to further refine the technique of PTMV, prob-
ably by using a low profile balloon and avoiding puncture of the muscular atrial septum. REFERENCES
1. Bashi W , Ravikumar E, JairajPS, Krishnaswami S, John S. Coexistent mitral valve disease with left-to-rightshunt at the atriallevel:clinicalprofile,hemodynamics, and surgicalconsiderations in 67 consecutive patients. A M HEART J 1987; 114:1406-14. 2. AI Zaibag M, Kasab SA, Ribeiro PA, Fagih MR. Percutaneous double balloon mitral valvotomy for the rheumatic mitral valve stenosis.Lancet 1986;1:757-61. 3. Inoue K, Nobuyoshi M, Chen C, et al. Advantage of Inoueballoon (self-positioningballoon)in percutaneous transvenous mitral commissurotomy. Circulation 1988;78(suppl II):490. 4. PalaciosIF, Block PC. Percutaneous mitral balloon valvotomy (PMV): update of immediate resultsand follow-up. Circulation 1988;78(suppl II):489. 5. Cormier B, Vahanian A, Michel PL, et al.The contributionof transesophageal echocardiography in the ultrasound assessment of percutaneous mitral valvuloplasty.J A m Coll Cardiol 1989;13:51A. 6. Cequier A, Bonan R, Dyrda I,et al.Atrial shunting afterpercutaneous mitral valvuloplasty. Circulation 1988;78(suppl II):488. 7. Palacios IF, Block PC. Atrial septal defect during percutaneous mitral balloon valvotomy (PMV): immediate resultsand follow-up. Circulation 1988;78(suppl II):529.
Brief Communications
Number 1
with a " y " descent equal or deeper than the "x" descent was present in 78.9% in group A and in 31.6% in group B (p < 0.00001). T h e results of the present study demonstrate t h a t VF or ventricular tachycardia requiring emergency countershock m a y occur in 0.85% of the patients s u b m i t t e d to hemodynamic monitoring and is an almost exclusive finding in patients with AMI, and more precisely with inferior A M I (Fig. 1). F u r t h e r m o r e , the presence of E C G findings of acute RVI, such as Q wave and S T segment elevation in right precordial lead V4R o r a noncompliant p a t t e r n in the right atrial pressure waveform permits the identification of a high-risk group of patients for this complication. Interestingly, the aforementioned criteria m a y be easily identified prior to the insertion of the catheter and a selection of patients can be made or extreme precautions can be taken. VF has also been related to manipulation of pacing electrodes in patients with acute right ventricular necrosis. 13 Sclarovsky et al. 13 reported the occurrence of VF in 5 of 30 patients with A M I who underwent ventricular pacing, and all five had right ventricular infarction. Ventricular fibrillation appeared in four cases when pacing was started and in one case during the i m p l a n t a t i o n of the catheter. The a r r h y t h m i a was repetitive in two cases secondary to electrical stimulation. Thus it seems t h a t there is a relation between right ventricular mechanical stimulation and VF when there is acute right ventricular necrosis. It seems reasonable to recommend t h a t in patients with suspected RVI, indications for hemodynamic monitoring should be reconsidered on an individual basis, and a fullyt r a i n e d cardiologist should perform the insertion of the catheter in the appropriate setting. No d a t a are available concerning the possible benefit of prophylactic use of ant i a r r h y t h m i c drugs in these patients. 7 When an episode of V F occurs during insertion of a catheter, a new a t t e m p t to correctly place the catheter into the pulmonary artery m a y be successful in most cases, b u t the possibilities of producing a new episode of VF is extremely high (5 of 23 patients, 21.7 %), and hemodynamic monitoring should be reserved for patients in whom the clinical m a n a g e m e n t otherwise would be considered very difficult. REFERENCES
1. Cairns JA. Ventricular fibrillation due to passage of a SwanGanz catheter. Am J Cardiol 1975;35:589. 2. Katz JD, Cronau LH, Barash PG, Mandel SD. Pulmonary artery flow-guided catheters in the perioperative period. JAMA 1977;237:2832-4. 3. Elliot CG, Zimmerman GA, Clemmer TP. Complications of pulmonary artery catheterization in the care of critically ill patients. A prospective study. Chest 1979;76:647-52. 4. Sprung CL, Jacobs LJ, Caralis PV, Karpf M. Ventricular arrhythmia during Swan-Ganz catheterization of the critically ill. Chest 1981;79:413-15. 5. Sise MJ, Hollingsworth P, Brimm JE, Peters RM, Virgilio RW, Shackford SR. Complications of the flow-directed pulmonary-artery catheter: a prospective analysis in 219 patients. Crit Care Med 1981;9:315-18. 6. Sprung C1, Pozen RG, Rozanski JJ, Pinero LR, Eisler BR, Castellanos A. Advanced ventricular arrhythmias during bedside pulmonary artery catheterization. Am J Med 1982;72: 203-8. 7. Salmenpera M, Peltola K, Rosenberg P. Does prophylactic lidocaine control cardiac arrhythmias associated with pulmonary artery catheterization? Anesthesiology 1982;56:210-12.
209
8. Dee Boyd K, Thomas SJ, Gold J, Boyd AD. A prospective study of complications of pulmonary artery catheterizations in 500 consecutive patients. Chest 1983;84:245-9. 9. Shah KB, Rao TL, Laughlin S, E1-Etr AA. A review of pulmonary artery catheterization in 6,245 patients. Anesthesiology 1984;61:271-5. 10. Blanco Paj6n MJ, Fernandez de la Reguera G, Hurtado Reyes IC, Molina M~ndez FJ, Blackaller Palacios R, Luna Ortiz P. Complicaciones del uso del cat~ter de flotaci6n en cirugia cardiovascular. Estudio prospectivo. Arch Inst Cardiol Mex 1986;56:147-55. 11. L6pez-Send6n J, Coma-Canella I, Alcasena S, Seoane J, Gamallo C. Electrocardiographic findings in acute right ventricular infarction: sensitivity and specificity of electrocardiographic alterations in right precordial leads V4R, V3R, V1, V2 and V3. J Am Coll Cardiol 1985;6:1273-9. 12. L6pez-Send6n J, Coma-Canella I, Gamallo C. Sensitivity and specificity of hemodynamic criteria in the diagnosis of acute right ventricular infarction. Circulation 1981;64:515-25. 13. Sclarovsky S, Zafrir Z, Strasberg B, Krakoff O, Lewin R, Arditi A, Rosen KM, Agmon J. Ventricular fibrillation complicating temporary ventricular pacing in acute myocardial infarction: significance of right ventricular infarction. Am J Cardiol 1981;14:101-3.
latrogenic Lutembacher's syndrome after percutaneous transluminal mitral valvotomy Chen-Huan Chen, MD, Shoa-Lin Lin, MD, Tsui-Lieh Hsu, MD, Chin-Chien Chen, MD, Shih-Pu Wang, MD, and Mau-Song Chang, MD. Taipei, Taiwan, Republic of
China
Lutembacher's syndrome, indicating coexistence of atrial septal defect (ASD) and rheumatic mitral valve disease, is a recognized pathologic e n t i t y J Whereas a nonrestrictive atrial septal defect can decompress the left atrium and attenuate the pulmonary venous congestion, the mitral valvular lesion may augment the left-to-right interatrial shunt and precipitate right-sided h e a r t failure. The following case illustrates the interesting hemodynamic interaction although the ASD had been " c r e a t e d " during the procedure of percutaneous transluminal mitral valvotomy (PTMV). A 35-year-old woman had experienced palpitation and exertional dyspnea for more t h a n 15 years and rheumatic mitral stenosis had been diagnosed by cardiac catheterization for 8 years. She was referred for PTMV. Clinical examination revealed a grade IV/VI diastolic rumbling murmur with opening snap at the apex. The electrocardiogram showed atrial fibrillation and right ventricular hypertrophy. T h e chest x-ray film showed cardiomegaly with pulmonary congestion. The two-dimensionaI echocardiogram (2-D echo) demonstrated typical rheumatic mitral stenosis (Fig. 1, A). Pulsed Doppler echocardiography From the Divisionof Cardiology,Department of Medicine,Veterans General Hospital-Taipei, and National Yang-Ming Medical College. Reprint requests:Dr. Mau-SongChang,Divisionof Cardiology,Department of Medicine,Veterans General Hospital-Taipei, Taipei, Taiwan, Republic of China. 4/4/16524
2 10
January 1990 American Heart Journal
Brief Communications
T a b l e I. Hemodynamic data before, immediately after, and 3 months after percutaneous transluminal mitral valvotomy
Heart rate (beats/min) Right atrium (ram Hg) Right ventricle (ram Hg) Pulmonary artery (ram Hg) Left atrium (ram Hg) Left ventricle (mm Hg) Aortic pressure (ram Hg) Mean pressure gradient (ram Hg) Mitral valve area (cm2) Cardiac output (L/min) Pulmonary-tosystemic flow ratio Shunt flow (L/rain)
Fig. 1. Short-axis views of the diastolic mitral valve ori-
fice before (A), immediately after (B), and 3 months after valvuloplasty (C). The successful splitting of the posterior commissure (arrow) resulted in significant increase in mitral valve area. No evidence of fusion of the commissure was noted 3 months later.
demonstrated trivial mitral regurgitation and moderate tricuspid regurgitation. PTMV was performed with double balloon technique. 2 Before the procedure, no interatrial shunt could be demonstrated by oximetry. Immediately after the procedure, a left-to-right atrial shunt was detected. 2-D echo performed 24 hours after the PTMV
Before
After
3 Months
60
84
100
7
10
15
57/6
70/10
43/9
61/30
75/32
51/24
29
17
16
120/13
106/8
133/11
119/70
96/68
120/98
18
8
10
0.4
1.2
0.7
2.3
4.8
3.0
1.0
1.83
3.24
0
2.2
5.7
demonstrated split posterior commissure and increased mitral orifice (Fig. 1, B). Mild mitral regurgitation and moderate tricuspid regurgitation were demonstrated by color-coded Doppler echocardiography. The patient was discharged with improved exercise tolerance. Three months after PTMV, progressive abdominal fullness, lower leg edema, and shortness of breath developed. The jugular veins were bouncing. A grade III/VI systolic murmur could be heard at both the pulmonic area and left lower sternal border. The liver was enlarged and pulsatile. Shifting dullness could be demonstrated. Moderate peripheral edema was present. 2-D echo showed well-preserved splitting of the posterior commissure without significant reduction in valvular area (Fig. 1, C). The right atrium was enlarged. Color Doppler echocardiography disclosed moderate to severe mitral regurgitation, severe tricuspid regurgitation, and a turbulent flow passing from the left atrium to the right atrium through a defect at the interatrial septum (Fig. 2). Follow-up left and right heart catheterization (Table I) suggested restenosis of the mitral orifice and the presence of a large left-to-right atrial shunt. She subsequently underwent open-heart surgery for repair of the ASD, replacement of a prosthetic mitral valve, and tricuspid annuloplasty. During the operation, a linear defect 1 cm in length at the muscular atrial septum beneath the fossa ovalis was found. The posterior commissure was split well to the mitral anulus without evidence of restenosis. The mitral anterior leaflet was redundant with prominent regurgitant capacity. The patient was subsequently discharged after an uneventful recovery.
Volume 119
Brie[ Communications
Number 1
211
Fig. 2. C•••r•••dedD•pp•erech•cardi•gramd•ne3m•nthsaftervalvu••p•astydem•nstratedaturbu•ent flow (arrowhead) passing from the left atrium (LA) to the right atrium (RA) and right ventricle (RV) through a defect at the interatrial septum.
Creation of a significant ASD secondary to the transseptal technique is perhaps the most frequent complication of PTMV. Whereas the incidence of interatrial left-to-right shunt determined by oximetry immediately after PTMV is around 15% to 20% in larger series 3, 4 and may be as high as 57 % by transesophageal color Doppler technique, 5 the short-term and long-term follow-up results are still limited.6, 7 Palacios et al. 7 suggested that ASD is hemodynamically well tolerated and that two thirds of them are closed at follow-up, which was certainly not true in our case. The magnitude of interatrial left-to-right shunt may be increased by coexisting mitral valve lesions. In the setting of PTMV, the persistent mitral inflow obstruction (either due to initial unsuccessful PTMV or to later restenosis), the prexisting or created significant mitral regurgitation, and inadvertent transseptal puncture over the muscular portion of the atrial septum may prevent the healing of ASD. Our case clearly demonstrated that the presence of hemodynamically significant ASD could result in deterioration of the clinically silent right-sided heart overload in patients with rheumatic mitral stenosis and mandate an imminent surgical repair and valvular replacement, which obviously canceled the beneficial effect of PTMV. Thus it is essential to further refine the technique of PTMV, prob-
ably by using a low profile balloon and avoiding puncture of the muscular atrial septum. REFERENCES
1. Bashi W , Ravikumar E, JairajPS, Krishnaswami S, John S. Coexistent mitral valve disease with left-to-rightshunt at the atriallevel:clinicalprofile,hemodynamics, and surgicalconsiderations in 67 consecutive patients. A M HEART J 1987; 114:1406-14. 2. AI Zaibag M, Kasab SA, Ribeiro PA, Fagih MR. Percutaneous double balloon mitral valvotomy for the rheumatic mitral valve stenosis.Lancet 1986;1:757-61. 3. Inoue K, Nobuyoshi M, Chen C, et al. Advantage of Inoueballoon (self-positioningballoon)in percutaneous transvenous mitral commissurotomy. Circulation 1988;78(suppl II):490. 4. PalaciosIF, Block PC. Percutaneous mitral balloon valvotomy (PMV): update of immediate resultsand follow-up. Circulation 1988;78(suppl II):489. 5. Cormier B, Vahanian A, Michel PL, et al.The contributionof transesophageal echocardiography in the ultrasound assessment of percutaneous mitral valvuloplasty.J A m Coll Cardiol 1989;13:51A. 6. Cequier A, Bonan R, Dyrda I,et al.Atrial shunting afterpercutaneous mitral valvuloplasty. Circulation 1988;78(suppl II):488. 7. Palacios IF, Block PC. Atrial septal defect during percutaneous mitral balloon valvotomy (PMV): immediate resultsand follow-up. Circulation 1988;78(suppl II):529.