摘要
Objective To monitor the influence of radiofrequency ablation (RFA) of tachycardia on cardiac structure and cardiac function. Methods 210 patients received routine RFA in our laboratory from March 1995 to March 1998. 104 of them underwent transesophageal echocardiography (TEE) procedure before RFA because of dissatisfactory results of the transthoracic echocardiography. 12 cases in 104 were found to have cardiac valvular insufficiency by TEE and they were excluded from our study. Totally 92 patients entered our serial study. 49 were men and 43 women aged from 16 to 61 years with an avarage of 34.2±11.0 years. The indications of RFA were frequent paroxysmal supraventricular tachycardia. The RFA energy we used ranged from 15 W to 40 W. The resistances were around 100 Ω. The times of radiofrequency current discharge were 60 seconds to 450 seconds with an avarage of 170±110 seconds. The cardiac electrophysiologic diagnosis from routine electrocardiography or transesophageal atrial pacing were left and right atrioventricular accessary pathways in 48 cases and 14 cases respectively, and atrioventricular dual reentrant pathway in 30 cases. TEE was performed before and three , ten days after the RFA. The procedure of TEE was the routine way as reported before with an I 5100 5 Mhz monoplane or a V 510 B 3.5 to 7.0 Mhz biplane phased array transducers. According to the synchronized electrocardiography, two dimensional supradiaphrag￣matic four chamber view was frozen at the end diastolic phase, the phase of the peak of the R wave on the electrocardiogram, and then, the end systolic phase, the phase of the near end of the T wave on the electrocardiogram. The endocardial border of the left ventricle was traced with a cursor and the volume of the left ventricle in the end diastole (EDV) and the end systole (ESV) were calculated by the computed sonographic system automatically. Left ventricular ejection fraction (EF) equalled (EDV-ESV)/EDV. Again the two dimensional supradiaphragmatic four chamber and five chamber pictures were viewed and the mitral valves, tricuspid valves and aortic valves including their morphology and motility were examined. Doppler color flow technique was used to detect the blood flow through the valves in order to detect the valvular regurgitation. Results RFA were successfully performed in all 92 patients in this study. There were no RFA related complications found during patients' hospitalization. All 92 TEE procedures before and three days, ten days after RFA were satisfactory. The left ventricular EF we calculated were around 0.57-0.61 with an avarage of 0.59±0.11. There were no statistically significant differences of left ventricular EF between before and after RFA or among the different tachycardia (P>0.05, individually). For the cardiac valves involved in RFA, there were no aortic valvular disorders after left accessary pathway RFA, but were 4 cases of mitral regurgitation (8.33%) three days after the procedure. These mitral regurgitations disappeared on TEE ten days after RFA. For the tricuspid valves involved in RFA of the right accessary pathways or atrioventricular dual pathways, 9 cases were found regurgitation (20.45%) three days after RFA. The regurgitations were more significant in 2 of the 9 patients. On TEE follow up ten days after RFA, tricuspid regurgitations remained in 4 cases including those two significant ones. That is, 30.76% (4/13) patients had valvular regurgitation remained ten days after RFA. Conclusion We consider that RFA is a relatively safe catheterization technique. There is no influence on the cardiac function but a slight damage to the involved cardiac valves after RFA. Most of the valvular damages could disappear in several days after RFA. But one third of these valvular disorders remain and need to be followed up.
Objective To monitor the influence of radiofrequency ablation (RFA) of tachycardia on cardiac structure and cardiac function. Methods 210 patients received routine RFA in our laboratory from March 1995 to March 1998. 104 of them underwent transesophageal echocardiography (TEE) procedure before RFA because of dissatisfactory results of the transthoracic echocardiography. 12 cases in 104 were found to have cardiac valvular insufficiency by TEE and they were excluded from our study. Totally 92 patients entered our serial study. 49 were men and 43 women aged from 16 to 61 years with an avarage of 34.2±11.0 years. The indications of RFA were frequent paroxysmal supraventricular tachycardia. The RFA energy we used ranged from 15 W to 40 W. The resistances were around 100 Ω. The times of radiofrequency current discharge were 60 seconds to 450 seconds with an avarage of 170±110 seconds. The cardiac electrophysiologic diagnosis from routine electrocardiography or transesophageal atrial pacing were left and right atrioventricular accessary pathways in 48 cases and 14 cases respectively, and atrioventricular dual reentrant pathway in 30 cases. TEE was performed before and three , ten days after the RFA. The procedure of TEE was the routine way as reported before with an I 5100 5 Mhz monoplane or a V 510 B 3.5 to 7.0 Mhz biplane phased array transducers. According to the synchronized electrocardiography, two dimensional supradiaphrag￣matic four chamber view was frozen at the end diastolic phase, the phase of the peak of the R wave on the electrocardiogram, and then, the end systolic phase, the phase of the near end of the T wave on the electrocardiogram. The endocardial border of the left ventricle was traced with a cursor and the volume of the left ventricle in the end diastole (EDV) and the end systole (ESV) were calculated by the computed sonographic system automatically. Left ventricular ejection fraction (EF) equalled (EDV-ESV)/EDV. Again the two dimensional supradiaphragmatic four chamber and five chamber pictures were viewed and the mitral valves, tricuspid valves and aortic valves including their morphology and motility were examined. Doppler color flow technique was used to detect the blood flow through the valves in order to detect the valvular regurgitation. Results RFA were successfully performed in all 92 patients in this study. There were no RFA related complications found during patients' hospitalization. All 92 TEE procedures before and three days, ten days after RFA were satisfactory. The left ventricular EF we calculated were around 0.57-0.61 with an avarage of 0.59±0.11. There were no statistically significant differences of left ventricular EF between before and after RFA or among the different tachycardia (P>0.05, individually). For the cardiac valves involved in RFA, there were no aortic valvular disorders after left accessary pathway RFA, but were 4 cases of mitral regurgitation (8.33%) three days after the procedure. These mitral regurgitations disappeared on TEE ten days after RFA. For the tricuspid valves involved in RFA of the right accessary pathways or atrioventricular dual pathways, 9 cases were found regurgitation (20.45%) three days after RFA. The regurgitations were more significant in 2 of the 9 patients. On TEE follow up ten days after RFA, tricuspid regurgitations remained in 4 cases including those two significant ones. That is, 30.76% (4/13) patients had valvular regurgitation remained ten days after RFA. Conclusion We consider that RFA is a relatively safe catheterization technique. There is no influence on the cardiac function but a slight damage to the involved cardiac valves after RFA. Most of the valvular damages could disappear in several days after RFA. But one third of these valvular disorders remain and need to be followed up.
