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Updated: Jan 24, 2026

Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR
Published on: April 8, 2013
A new method to recommend left ventricular lead positions for improved CRT volumetric response and long-term
Xinwei Zhang1, Zhiyong Qian1, Haipeng Tang2
1Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Guangzhou Road 300, Nanjing, 210029, Jiangsu, China.
Objectives:
Using ECG-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), we sought to develop and validate a new method to recommend left ventricular (LV) lead positions in order to improve volumetric response and long-term prognosis after cardiac resynchronization therapy (CRT).
Methods:
Seventy-nine patients received gated SPECT MPI at baseline, and echocardiography at baseline and follow-up. The volumetric response referred to a reduction of ≥ 15% in LV end-systolic volume 6 months after CRT. After excluding apical, septal, and scarred segments, there were three levels of recommended segments: (1) the optimal recommendation: the latest contracting viable segment; (2) the 2nd recommendation: the late contracting viable segments whose contraction delays were within 10° of the optimal recommendation; and (3) the 3rd recommendation: the viable segments adjacent to the optimal recommendation when there was no late contracting viable segment.
Results:
After excluding 11 patients whose LV lead was placed in apical or scarred segments, 75.6% of the patients concordant to recommended LV segments (n = 41) responded to CRT while 51.9% of those with non-recommended LV lead locations (n = 27) were responders (P = .043). Response rates were 76.9%, 76.9% , and 73.3% (P = .967), respectively, when LV lead was implanted in the optimal recommendation (n = 13), the 2nd recommendation (n = 13), and the 3rd recommendation (n = 15). LV leads placed at recommended segments reduced composite events of all-cause mortality or heart failure (HF) rehospitalization compared with pacing at non-recommended segments (log-rank χ2 = 5.623, P = .018).
Conclusions:
Pacing in the recommended LV lead segments identified on gated SPECT MPI was associated with improved volumetric response to CRT and long-term prognosis.
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