Metrics of electrical dyssynchrony and electrical activation patterns from surface ecg electrodes

A method of cardiac pacing comprising:

• a) determining a baseline rhythm using a plurality of body-surface electrodes;
• (b) determining a set of baseline functional electrical metrics in response to determining the baseline rhythm;
• (c) delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode;
• (d) determining a set of functional electrical metrics relating to cardiac depolarization and repolarization in response to resynchronization pacing;
• (e) determining whether relative reduction of a first functional electrical metric from the set of functional electrical metrics in step d exceeds X % of a first electrical functional metric from the set of baseline functional electrical metrics in step b;
• (f) determining whether an absolute value of a second functional electrical metric from the set of the functional electrical metrics is less than Y ms;
• and
• (g) determining that a site is responsive to CRT in response to determining whether steps e) and f) are met.

A system of cardiac pacing comprising:

• a) processing means for determining a baseline rhythm using a plurality of body-surface electrodes;
• (b) processing means for determining a set of baseline functional electrical metrics in response to determining the baseline rhythm;
• (c) delivering means for delivering resynchronization pacing using a right ventricular electrode and a pacing left ventricular electrode or only with a left ventricular electrode;
• (d) processing means for determining a set of functional electrical metrics relating to cardiac depolarization and repolarization in response to resynchronization pacing;
• (e) processing means for determining whether relative reduction of a first functional electrical metric from the set of functional electrical metrics in step d exceeds X % of a first electrical functional metric from the set of baseline functional electrical metrics in step b;
• (f) processing means for determining whether an absolute value of a second functional electrical metric from the set of the functional electrical metrics is less than Y ms;
• and
• (g) processing means for determining that a site is responsive to CRT in response to determining whether steps e) and f) are met.