Early Results of Maze III Operation Without Cryoablation / 대한흉부외과학회지

BACKGROUND: Atrial fibrillation is one of the most prevalent of all arrhythmias and in up to 79% of the patients with mitral valve disease. This study examined whether the atrial fibrillation that occur in patients with mitral valve operation could be eliminated by a concommitant maze operation without cryoablation. MATERIAL AND METHOD: From May 1997 to April 1998, 14 patients with atrial fibrillation associated with mitral valve disease underwent Maze III operation without cryoablation. Preoperatively there were 6 men and 8 women with an average age of 46.2+/-10.7 years. Eleven patients had mitral stenosis, and three had mitral insufficiency. The associated heart diseases were aortic valve disease in 4, tricuspid valve regurgitation in 1 and ASD in 2. Using transthoracic echocardiography, the mean left atrial diameters was 54.7+/-5.3 mm and thrombi were found in the left atrium of 2 patients. Postoperatively the ratio between the peak speed of the early filling wave and that of the atrial contraction wave (A/E ratio) was determined from transmitral flow measurement. Operations were mitral valve replacement in 13 including 4 aortic valve replacements, 1 DeVega annuloplasty and 2 ASD closures. Maze III operation was performed in 1 patient. RESULT: Five patients (38%) had recurred atrial fibrillation, which was reversed with flecainide or amiodarone at the average time of postoperative 38.8+/-23.5 days. Postoperative complications were postoperative transient junctional rhythm in 6, transient atrial fibrillation in 5, reoperation for bleeding in 3, postpericardiotomy syndrome(1), unilateral vocal cord palsy(1), postoperative psychosis(1), and myocardial infarction(1). Postoperatively A/E ratio was 0.43+/-0.22 and A wave found in 9(64%) patients. 3 to 14 months postoperatively (average follow- up, 8.1 months), all of patients had normal sinus rhythm and 9(64%) patients had left atrial contraction and 11(79%) patients were not on a regimen of antiarrhythmic medication. CONCLUSION: We conclude that Maze III operation without cryoablation is an effective surgical treatment in atrial fibrillation associated with the mitral valve disease.

Effects of percutaneous mitral valvuloplasty on pulmonary venous flow velocities in patients with mitral stenosis

BACKGROUND: Recent development of transesophageal echocardiography(TEE) makes it possible to record pulmonary venous flow velocities(PVFV) accurately. To observe the differences of PVFV between normal controls and patients with severe mitral stenosis and to clarify the effects of percutaneous mitral valvuloplasty(PMV) on PVFV, TEE was performed in 12 normal controls and 11 patients with severe mitral stenosis. METHODS: PVFV was recorded from left upper pulmonary vein in longitudinal view of midesophageal position with a 5 MHz probe. Peak velocity and velocity-time integral(VTI) of systole and diastole were calculated with a digitizer. TEE was performed before and one day after PMV. Hemodynamic data(left atrial pressure, transmitral diastolic pressure gradient and cardiac output) were analyzed to demonstrate the possible correlation with PVFV. RESULTS: 1) 75%(9/12) of normal controls showed 4 distinct phases of PVFV with 2 systolic forward peaks, I diastolic forward and I end-diastolic backward peak. Peak systolic velocity was 52.6+/-.9cm/sec and peak diastolic forward velocity was 36.0+/-10.3cm/sec : Systolic VTI was greater than diastolic VTI, too(11.1+/-3.6cm vs 5.2+/-.6cm). 2) In patients with tight mitral stenosis(mean mitral area : 0.9cm2), most(10/11, 91%) showed one peak of systolic forward flow : Peak systolic velocity(27.8+/-15.8cm/sec) and systolic velocity-time integral(3.4+/-1.8cm)were significantly smaller than those of normal controls, while there was no statistical difference in peak diastolic forward velocity and velocity-time integral(34.5+/-12.7cm/sec, 4.3+/-1.7cm) compared to normal controls. There were no significant differences according to the rhythm. After successful PMV(mean mitral valve area : 1.9cm2) peak systolic and diastolic velocities increased up to 46.9+/-13.8cm/sec, 41.4+/-7.5cm/sec respectively, and systolic increase was statistically significant. The systolic increase of peak pulmonary venous velocity and velocity-time integral was more prominent in normal sinus group compared to patients with atrial fibrillation. 3) In patients with mitral stenosis, there was no correlation between peak diastolic forward velocity of pulmonary vein and peak transmitral early diastolic velocity(r=-0.19, p=0.40) : There was a weak negative correlation between mean left atrial pressure and peak systolic velocity of pulmonary vein(r=-0.46, p=0.03) in the pooled data of pre- and postvalvuloplasty(N=22). Also there noticed a negative correlation between diastolic transmitral pressure gradient and peak diastolic velocity of pulmonary vein(r=-0.49, p=0.02, N=22). CONCLUSION: Pulmonary venous velocities of patients with tight mitral stenosis showed decreased peak systolic velocity and VTI due to increased left atrial pressure and decreased compliance. which normalized immediately after successful PMV. In patients with mitral stenosis there seems to be somewhat different relationships between hemodynamic indices and pulmonary venous flow velocities, and further study with more patients with variable mitral valve area would be necessary to clarify the exact correlation.