Morphology-based ECG criteria for identifying left-atrial low-voltage areas on voltage mapping: a diagnostic accuracy study

Figures

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  Figure 1. Exclusion of patients.

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  Figure 2. Study workflow.

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  Figure 3. Description of the 4 ECG criteria.

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  Figure 4. An example of negative atrial vector attenuation. leads V1–V2 of a 12-lead ECG (40 mm/mV, 50 mm/s) in Sinus rhythm before first-time ablation. The baseline is defined as the isoelectric point immediately preceding the P-wave onset. The positive amplitude is measured as the maximum peak deflection above baseline, and the negative amplitude as the maximum peak deflection below baseline, both measured from this same pre-P-wave baseline. In cases where multiple deflections are present, the largest amplitude in each direction is used for the ratio calculation. (A) A normal negative atrial vector in a 70-year old patient with persistent AF, moderate dilatation, no significant low-voltage areas on invasive voltage mapping. (B) Negative atrial vector attenuation in a 76-year old patient with persistent AF, mild dilatation, diffuse low-voltage areas.

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  Figure 5. An example of poor terminal P-wave progression in leads V4–V6, defined as either a negative or iso-electric segment in the second half of the P-wave duration in at least two of leads V4–V6. The second half is defined temporally as the latter 50% of total P-wave duration, measured from P-wave onset to offset. leads V3–V6 of a 12-lead ECG (40 mm/mV, 50 mm/s) in Sinus rhythm before first-time ablation. (A) Normal terminal P-wave progression V4–V6 in a 69 year-old patient, persistent AF, mild left atrial dilatation, low-voltage areas <5%. (B) Poor terminal P-wave progression V4–V6 in a 83 year-old patient, persistent AF, mild left atrial dilatation, diffuse low-voltage areas.

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  Figure 6. Two representative cases illustrating the relationship between 12-lead ECG morphology and invasive left atrial voltage mapping. For each case, the 12-lead ECG (40 mm/mV, 50 mm/s, recorded in sinus rhythm before first-time ablation) is shown on the left, with the corresponding invasive bipolar voltage map (CARTO 3) on the right. Purple indicates normal bipolar voltage (>0.50 mV); colors approaching red and yellow indicate progressively lower voltages. (A) All criteria negative in a 57-year old patient with paroxysmal AF, mild left atrial dilatation. On invasive voltage mapping no significant low-voltage areas. (B) presence of advanced interatrial block and poor terminal p-wave progression (red arrows) in a 62-year old patient, persistent AF, severe left atrial dilatation, low voltage areas mostly around the anterior wall.

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  Figure 7. AUC analysis and ROC curves for different screening methods.