Table 3. Electrocardiographic parameters.

		Derivation Group				Validation Group
Parameters	Controls	DD 1	DD 2	p-value*	Controls	DD 1	p-value*
Heart rate (bpm)	67 ± 10	78 ± 11	73 ± 12	< 0.0001	71 ± 14	77 ± 12	0.1
Heart rate Echo (bpm)	69 ± 12	72 ± 9	67 ± 11	0.2†	69 ± 15	75 ± 15	0.7†
P wave duration (ms)	105 ± 18	114 ± 19	110 ± 20	< 0.01	101 ± 11	113 ± 21	< 0.0001
P wave amplitude (mV)	0.11 ± 0.04	0.11 ± 0.04	0.08 ± 0.03	0.1	0.11 ± 0.06	0.12 ± 0.06	0.1
PQ (ms)	153 ± 22	169 ± 28	171 ± 38	< 0.005	145 ± 22	167 ± 30	Q
Pend - Q (ms)	48 ± 21	54 ± 28	61 ± 38	0.09	44 ± 19	54 ± 23	0.07
P wave dispersion	50 ± 16	58 ± 16	62 ± 20	< 0.005	51 ± 17	57 ± 18	< 0.005
QRS (ms)	89 ± 12	90 ± 16	96 ± 14	0.2	88 ± 14	90 ± 13	0.7
QT (ms)	390 ± 33	371 ± 29	397 ± 38	< 0.005	388 ± 36	388 ± 30	1
QTc (ms)	409 ± 25	422 ± 24	434 ± 32	< 0.0005	416 ± 28	438 ± 32	< 0.05
Tpeak - Tend	69 ± 11	66 ± 12	72 ± 18	0.2	71 ± 14	69 ± 17	0.7
Tpeak - Tend dispersion	36 ± 14	35 ± 18	42 ± 15	0.4	38 ± 16	37 ± 17	0.6
QT dispersion	43 ± 17	44 ± 23	57 ± 33	0.09	45 ± 21	49 ± 23	0.3
QTc dispersion	46 ± 17	50 ± 26	64 ± 39	0.09	48 ± 16	49 ± 21	0.5
U wave (n/%)	27 (33)	22 (33)	7 (50)	0.8	15 (30)	16 (32)	0.9
Tend - P (ms)	373 ± 110	240 ± 78	276 ± 108	< 0.0001	349 ± 152	237 ± 131	< 0.0005
Tend - Q (ms)	526 ± 119	409 ± 85	447 ± 115	< 0.0001	494 ± 141	404 ± 129	< 0.0001

DD 1 and 2 indicates diastolic dysfunction grade 1 and 2, * p value is given for the comparison of Controls vs DD (ANOVA in the derivation group), values are given as mean ± SD or numbers and percentages, † p = ns for the comparison of heart rate values during echocardiographic vs. heart rate values during ECG in Controls and DD, respectively.