Acute effects of using an electronic nicotine-delivery device (electronic cigarette) on myocardial function: comparison with the effects of regular cigarettes

Table 3 Tissue Doppler velocity and longitudinal deformation measurements in electronic cigarette users (ECIG, n = 40) and smokers (SM, n = 36), before and after device and cigarette use respectively*

Parameter	Before use	After use	Change	P-value^a	P-value^b
Sm (cm/s)
ECIG	9.7 ± 1.6	9.9 ± 1.6	0.2 ± 0.7	0.171	0.613
SM	9.7 ± 1.4	9.7 ± 1.5	-0.8 ± 1.1	0.571
P-value^c	0.896	0.723
Em (cm/s)
ECIG	12.7 ± 1.9	12.9 ± 2.1	0.2 ± 0.7	0.095	< 0.001
SM	12.8 ± 2.1	11.9 ± 1.5	-0.7 ± 1.4	< 0.001
P-value^c	0.892	0.032
Am (cm/s)
ECIG	9.7 ± 1.7	9.9 ± 1.6	0.2 ± 0.8	0.122	0.441
SM	9.3 ± 1.2	9.4 ± 1.3	0.1 ± 0.6	0.801
P-value^c	0.212	0.099
Em/Am
ECIG	1.34 ± 0.29	1.33 ± 0.28	-0.01 ± 0.13	0.540	0.011
SM	1.40 ± 0.28	1.30 ± 0.24	-0.08 ± 0.13	0.004
P-value^c	0.408	0.655
E/Em
ECIG	5.60 ± 1.04	5.61 ± 1.11	0.01 ± 0.47	0.869	0.052
SM	5.83 ± 0.95	6.10 ± 0.98	0.29 ± 0.74	0.021
P-value^c	0.311	0.044
MPIt
ECIG	0.48 ± 0.08	0.47 ± 0.09	-0.01 ± 0.04	0.080	< 0.001
SM	0.49 ± 0.06	0.52 ± 0.07	0.03 ± 0.05	0.004
P-value^c	0.654	0.019
GS (%)
ECIG	-21.1 ± 1.9	-21.5 ± 1.6	-0.4 ± 1.2	0.059	0.087
SM	-21.0 ± 2.6	-20.7 ± 3.1	0.2 ± 1.7	0.441
P-value^c	0.769	0.192
SRs (s ^-1 )
ECIG	-1.13 ± 0.10	-1.14 ± 0.11	-0.01 ± 0.07	0.362	0.613
SM	-1.08 ± 0.13	-1.10 ± 0.13	-0.2 ± 0.1	0.150
P-value^c	0.059	0.115
SRe (s ^-1 )
ECIG	1.47 ± 0.25	1.49 ± 0.23	0.01 ± 0.08	0.347	< 0.001
SM	1.43 ± 0.25	1.35 ± 0.24	-0.08 ± 0.12	< 0.001
P-value^c	0.493	0.022
SRa (s ^-1 )
ECIG	0.88 ± 0.20	0.89 ± 0.18	0.01 ± 0.08	0.462	0.441
SM	0.86 ± 0.14	0.88 ± 0.14	0.03 ± 0.09	0.111
P-value^c	0.536	0.796

*Longitudinal deformation measurements were performed in 37 electronic cigarette users and 34 smokers.
Sm, mitral annulus systolic velocity; Em, mitral annulus early diastolic velocity; Am, mitral annulus late diastolic velocity; MPIt, myocardial performance index estimated by tissue Doppler echocardiography; GS, global longitudinal strain; SRs, peak systolic strain rate; SRe, peak early diastolic strain rate; SRa, peak late diastolic strain rate.
^aP-value for time effect.
^bRepeated measurements ANOVA. Effects reported are significant differences between the two groups in the degree of change in each particular variable.
^cP-value for group effect.

ISSN: 1471-2261