Development of an echocardiographic method for choosing the best fitting single-pass VDD lead.
To achieve stable single-lead VDD pacing, a selection of the electrode with the optimal distance between the lead tip and the floating atrial dipole (AV distance [AVD]) is important. The authors hypothesized that the size of the right heart chambers may affect atrial sensing, and that measurement of their internal dimension at end-diastole (RHIDd) in the apical four chamber view by transthoracic echocardiography may aid in choosing the proper AVD. Twenty-six consecutive cases that had undergone VDD pacer implantation using the conventional chest X ray were examined retrospectively by the echocardiographic method. The chest x-ray method properly selected a lead with optimal atrial sensing, defined as minimum P wave amplitude > or = 1.0 mV, for only 20 (77%) of 26 patients. By comparing these results with their respective RHIDd, a cut-off point of 13 cm was obtained that indicated a criterion for choosing the proper AVD. The indication was that if the RHIDd was > or = 13 cm, a lead with an AVD of 15.5/16 cm should have been used; if the RHIDd was < 13 cm, a lead with an AVD of 13/13.5 cm should have been chosen. Using the echocardiographic method, all six patients who had suboptimal atrial sensing could be identified and classified as having missized (four undersized; two oversized) permanent leads. In conclusion, the described method provides a promising preoperative assessment of the best fitting electrode length in single lead VDD pacing. A prospective study is ongoing to verify its applicability.
Yin
Wei-Hsian
WH
Heart Center, Cheng-Hsin General Hospital and the National Yang-Ming University, School of Medicine, Taipei, Taiwan. chinfung@dreamer.com.tw
Jen
Hsu-Lung
HL
Chiang
Meng-Cheng
MC
Chuang
Yi-Cheng
YC
Chang
Chung-Yi
CY
Young
Mason Shing
MS
Wei
Jeng
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004452:Echocardiography / Q000379:methods*; D004567:Electrodes, Implanted; D005260:Female; D006321:Heart / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D006331:Heart Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography