Author Affiliations:
1. King Abdulaziz Medical City - National Guard Health Affairs, Riyadh, Kingdom of Saudi Arabia
2. King Fahad Armed Forces Hospital, Jeddah, Kingdom of Saudi Arabia
3. Prince Sultan Cardiac Center, Riyadh, Kingdom of Saudi Arabia
4. King Faisal Hospital and Research Center, Riyadh, Kingdom of Saudi Arabia
5. King Abdulaziz University Hospital, Jeddah, Kingdom of Saudi Arabia
6. National Heart Center at the Royal Hospital, Muscat, Oman
7. King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia
Brief Title: Reverse Remodeling by MultiPoint Pacing in the Middle East
Word count: 4,536
Funding Sources: This study was funded by Abbott.
Conflicts of Interest: Najib Al Rawahi, Fayez Bokhari, Raed Sweidan, Ahmed Al Fagih, Yahya Al Hebaishi, Ahmed Al Fagih, Ahmad Hersi, Naeem Al Shoaibi, and Maria Loricchio received research grants and/or consultancy fees from Abbott. Alexandre Chami and Nima Badie are employees of Abbott.
Corresponding Author: Abdulmohsen Almusaad, MD King Abdalaziz Medical City
National Guard Health Affairs
Riyadh, Kingdom of Saudi Arabia
Telephone: +966 50 323 1833
E-mail: a_almusaad@yahoo.com Abstract
Introduction :  Cardiac resynchronization therapy (CRT) with multipoint left ventricular (LV) pacing (MultiPoint™ Pacing, MPP) has been shown to improve CRT response, although MPP response using automated pacing vector programming has not been demonstrated in the Middle East.
Objective: Compare the impact of MPP to conventional biventricular pacing (BiV) using echocardiographic and clinical changes at 6 months post-implant.
Methods : This prospective, randomized study was conducted at 13 Middle Eastern centers. After de novo CRT-D implant (Abbott Unify Quadra MP™ or Quadra Assura MP™) with quadripolar LV lead (Abbott Quartet™), patients were randomized to either BiV or MPP therapy. In BiV patients, the LV pacing vector was selected per standard practice; in MPP patients, the two LV pacing vectors were selected automatically using VectSelect. CRT response was defined at 6 months post-implant by a reduction in LV end-systolic volume (ESV) ≥15%.
Results :  One-hundred and forty-two patients (61 years old, 68% male, NYHA class II/III/IV 19%/75%/6%, 33% ischemic, 57% hypertension, 52% diabetes, 158 ms QRS, 25.8% ejection fraction [EF]) were randomized to either BiV (N=69) or MPP (N=73). After 6 months, MPP vs. BiV patients experienced greater ESV reduction (25.0% vs. 15.3%, P=0.08), greater EF elevation (11.9% vs. 8.6%, P=0.36), significantly greater ESV response rate (68.5% vs. 50.7%, P=0.04), and significantly greater NYHA class improvement rate (80.8% vs. 60.3%, P=0.01).
Conclusions :  With MPP and automatic LV vector selection, more CRT patients in the Middle East experienced reverse remodeling and clinical improvement relative to conventional BiV pacing.
Keywords: Cardiac resynchronization therapy; heart failure; reverse remodeling; multipoint pacing