Table 5.

QT Interval Rate Dependence

	Mitral Valve Prolapses	Healthy Relatives	Healthy Volunteers	P Valuea
QT end/R‐R slope 24 hours	0.21 ± 0.07	0.19 ± 0.07	0.19 ± 0.05	NS/NS/NS
QT end/R‐R slope day	0.17 ± 0.06	0.15 ± 0.07	0.16 ± 0.05	NS/NS/NS
QT end/R‐R slope night	0.16 ± 0.06	0.13 ± 0.04	0.11 ± 0.06	0.019/0.001/NS
QT apex/R‐R slope 24 hours	0.19 ± 0.05	0.20 ± 0.04	0.20 ± 0.04	NS/NS/NS
QT apex/R‐R slope day	0.17 ± 0.05	0.17 ± 0.04	0.18 ± 0.04	NS/NS/NS
QT apex/R‐R slope night	0.14 ± 0.05	0.14 ± 0.05	0.13 ± 0.05	NS/NS/NS

^aMitral valve prolapses versus healthy relatives/mitral valve prolapses versus healthy volunteers/healthy relatives versus healthy volunteers.