Acoustic cardiac triggering: a practical solution for synchronization and gating of cardiovascular magnetic resonance at 7 Tesla

Table 1 Synopsis of the trigger detection variance assessment

	Mean cardiac interval length			Standard deviation of the mean cardiac interval length			Standard deviation of the cardiac trigger offset
Subject	(ms)			(ms)			(ms)
	ACT	ECG	POX	ACT	ECG	POX	ACT	ECG	POX
1	869	865	840	89	54	45	78	10	11
2	870	795	1103	83	126	87	76	477	101
3	875	845	834	48	28	34	13	3	19
4	1064	999	1079	76	143	52	44	456	456
5	926	990	923	49	54	31	14	56	23
6	841	939	898	95	69	35	149	52	15
7	848	839	876	79	62	48	75	257	67
8	1110	886	1091	37	174	33	1	1047	14
9	762	576	660	81	168	144	112	488	331

Synopsis of the mean R-R interval lengths, standard deviation of the mean R-R interval lengths and standard deviation of the cardiac trigger detection offset deduced from the signal waveforms of ECG, POX and ACT triggered acquisitions. A significant difference in the standard deviation of the R-R interval length deduced from ECG, ACT and POX waveforms indicates trigger misregistration. A large standard deviation of the offset between the ECG's R-wave and the trigger detection which was derived from the ECG, POX and ACT waveforms indicates trigger misregistration

ISSN: 1532-429X