Correlation between impedance cardiography and 6 min walk distance in atrial fibrillation patients.
The correlation between impedance cardiography (ICG) and 6 min walk distance (6MWD) in atrial fibrillation (AF) patients remains unknown.



We recruited 49 subjects in the study (21 AF patients and 28 patients without AF) and estimated hemodynamic parameters: cardiac output (CO), stroke volume (SV), stroke volume index (SVI), left stroke work (LSW), left stroke work index (LSWI), stroke systemic vascular resistance (SSVR), stroke systemic vascular resistance index (SSVRI); 6MWD, left ventricle ejection fraction (LVEF), NT-pro brain natriuretic peptide (NT-pro BNP) for the two groups.



The AF group have apparently lower CO (2.26 ± 0.14 VS 4.11 ± 0.20 L/min, p = 0.039) and distinctly higher SVR (677.60 ± 69.10 VS 344.41 ± 22.98 dynes/cm(5), p = 0.001), SSVRI (396.97 ± 36.80 VS 199.01 ± 11.72 dynes/cm(5)/m(2), p < 0.001) than the control group. NT-pro BNP (1409.48 ± 239.90 VS 332.59 ± 68.85 pg/ml, p = 0.001) in the AF group was significantly higher than the control group and 6MWD (264.33 ± 14.55 VS 428.79 ± 29.98 m, p < 0.001) in the AF group was lower than the control group. There was no significant difference in LVEF between the two groups (62.67 ± 7.62 % VS 63.93 ± 5.03 %, p = 0.470). Pearson correlation analysis revealed that CO (R = 0.494, p = 0.023), SV (R = 0.633, p = 0.002), LSW (R = 0.615, p = 0.003) and LSWI (R = 0.491, p = 0.024) significantly correlated positively with 6MWD in AF patients.



AF patients had lower cardiac output, shorter 6MWD and higher NT-pro BNP than patients with sinus rhythm. The cardiac output measured by impedance cardiography significantly correlated positively with 6MWD in AF patients.
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Ling
L
Ding
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Xiao-Qing
XQ
Quan
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Shu
S
Zhang
Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Lei
L
Ruan
Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Le
L
Zhang
Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Kai
K
Zheng
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Wei-Wei
WW
Yu
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Xiao-Fen
XF
Wu
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Tao
T
Mi
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Cun-Tai
CT
Zhang
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China. zhouhonglian63@163.com.
Hong-Lian
HL
Zhou
D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D002307:Cardiography, Impedance; D016022:Case-Control Studies; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011237:Predictive Value of Tests; D013318:Stroke Volume; D014655:Vascular Resistance; D016277:Ventricular Function, Left; D000070857:Walk Test
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
6 min walk distance; Atrial fibrillation; Impedance cardiography