1. Volume 12, Issue 10, Pages 2141-2147 (October 2015)
Prominent R wave in ECG lead V1 predicts improvement of left ventricular ejection fraction after cardiac resynchronization therapy in patients with or without left bundle branch block 
Weeranun D. Bode, MD, Michael F. Bode, MD, Leonard Gettes, MD, Brian C. Jensen, MD, John P. Mounsey, BMBCh, PhD, Eugene H. Chung, MD, FHRS 
Heart Rhythm 
Volume 12, Issue 10, Pages (October 2015)
DOI: /j.hrthm
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2. Figure 1
A–C: Examples of positive biventricular (BiV) paced ECG morphology (R/S ≥1 in lead V1 and/or R/S ≤1 in lead I). A: V1: R = 8 mm, S = 5 mm, R/S = 1.6; lead I: R = 0 mm, S = 7 mm, R/S = 0. B: V1: R = 6 mm, S = 5 mm, R/S 1.2; lead I: R = 3 mm, S = 3 mm, R/S = 1. C: V1: R = 4 mm, S = 12 mm, R/S = 0.33; lead I: R = 0 mm, S = 7 mm, R/S = 0. D, E: Examples of negative BiV paced ECG morphology. D: V1: R = 4 mm, S = 12 mm, R/S = 0.33; lead I: R = 6 mm, S = 3 mm, R/S = 2. E: V1: R = 0 mm, S = 11 mm, R/S = 0; lead I: R = 5 mm, S = 1 mm, R/S = 5
Heart Rhythm  , DOI: ( /j.hrthm )
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3. Figure 2
Study algorithm. BiV = biventricular; LVEF = left ventricular ejection fraction.
Heart Rhythm  , DOI: ( /j.hrthm )
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4. Figure 3
Results. Thirty-six patients were responders (left ventricular ejection fraction [LVEF] improvement ≥7.5%), and 32 patients were nonresponders (LVEF improvement <7.5%). Of the responders, 34 (94%) showed positive biventricular (BiV) paced ECG morphology, and 2 (6%) showed negative BiV paced ECG morphology. Of the nonresponders, 15 (47%) showed positive BiV paced ECG morphology, and 17 (53%) showed negative BiV paced ECG morphology (χ2 = 19.04, P < .0001).
Heart Rhythm  , DOI: ( /j.hrthm )
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5. Figure 4
Left ventricular ejection fraction (LVEF) improvement (%) for patients with positive biventricular (BiV) paced ECG morphology (14.3%; 95% confidence interval 10.91–17.62) (white) and negative BiV paced ECG morphology (2.6%; 95% confidence interval 0.78–4.49) (black). *P =
Heart Rhythm  , DOI: ( /j.hrthm )
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6. Figure 5
Left bundle branch block (LBBB) and left ventricular ejection fraction (LVEF) improvement. Of the responders, 21 (60%) were diagnosed with LBBB, and 14 (40%) were diagnosed with non-LBBB. Of the nonresponders, 13 (41%) were diagnosed with LBBB, and 19 (59%) were diagnosed with non-LBBB (χ2 = 2.51, P = .113).
Heart Rhythm  , DOI: ( /j.hrthm )
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7. Figure 6
Left bundle branch block (LBBB) and biventricular (BiV) ECG morphology criteria. Patients by LBBB status on their preprocedural ECG and prediction of response by BiV ECG morphology criteria on their postprocedural ECG. One patient with chronic right ventricular pacing was not included in this analysis, thus reducing the number of patients with non-LBBB to 33. Asterisk denotes presence of right bundle branch block (RBBB) in nonresponders: 1 nonresponder with non-LBBB /+BiV ECG had RBBB, and 4 nonresponders with non-LBBB/–BIV ECG had RBBB. +BiV ECG = positive BiV paced ECG morphology; –BiV ECG = negative BiV paced ECG morphology; RBBB = right bundle branch block.
Heart Rhythm  , DOI: ( /j.hrthm )
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