| Summary: | Background: The heart ejects in the central elastic arteries. No previous study addressed the question whether ECG voltages are more closely associated with central than with peripheral blood pressure (BP).
Methods: Using the oscillometric Mobil-O-Graph 24 h PWA monitor, we measured brachial, central BP and central hemodynamics over 24 hours in 177 men (mean age, 29.1 years), and linked to ECG voltages.
Results: From wakefulness to sleep, as documented by diaries, systolic/diastolic BP decreased by 11.7/13.1 mmHg peripherally and by 9.3/13.6 mmHg centrally, whereas pulse pressure (PP) increased by 4.3 mmHg. Over 24 hours and the awake and asleep periods, the peripheral-minus-central differences in systolic/diastolic BPs and pulse pressure averaged 11.8/–1.6, 12.7/–1.8 and 10.3/–1.2 mmHg and 13.4, 14.4 and 11.5 mmHg, respectively (P < 0.0001). Cornel voltage and index averaged 1.18 mV and 114.8 mV×ms. The Cornell voltages were 0.104/0.086 and 0.082/0.105 mV higher in relation to brachial 24-h and asleep systolic/diastolic BP (per 1-SD), respectively, and 0.088/0.90 mV and 0.087/0.107 mV higher in relation to central BP. The corresponding estimates for the Cornel indexes were 9.6/8.6 and 8.2/105 mV×ms peripherally and 8.6/8.9 and 8.8/10.7 mV×ms centrally. The regression slopes were similar for brachial and central BP (P≥0.054). Associations of the ECG measurements with awake BP, PP, the augmentation ratio and pressure amplification did not reach significance.
Cornell voltage (SV3 + RaVL, mV)
Cornell index (Cornell voltage × QRS duration, mV·ms)
Peripheral BP
Central BP
Peripheral BP
Central BP
Estimate (95% CI)
P
Estimate (95% CI)
P
Estimate (95% CI)
P
Estimate (95% CI)
P
Systolic BP
24-h
0.104 (0.016 to 0.191)
0.021
0.088 (0.0003 to 0.177)
0.049
9.61 (0.65 to 18.57)
0.036
8.58 (−0.40 to 17.56)
0.061
Awake
0.086 (−0.001 to 0.175)
0.054
0.062 (−0.026 to 0.151)
0.17
7.69 (−1.30 to 16.69)
0.093
5.80 (−3.23 to 14.82)
0.21
Asleep
0.082 (−0.006 to 0.170)
0.068
0.087 (−0.001 to 0.175)
0.053
8.17 (−0.82 to 17.16)
0.075
8.76 (−0.217 to 17.74)
0.056
Diastolic BP
24-h
0.086 (−0.002 to 0.174)
0.056
0.090 (0.002 to 0.178)
0.045
8.57 (−0.41 to 17.55)
0.061
8.93 (−0.04 to 17.90)
0.051
Awake
0.056 (−0.032 to 0.145)
0.21
0.060 (−0.029 to 0.149)
0.18
5.62 (−3.42 to 14.65)
0.22
5.97 (−3.06 to 15.00)
0.19
Asleep BP
0.105 (0.017 to 0.192)
0.020
0.107 (0.019 to 0.194)
0.017
10.53 (1.60 to 19.47)
0.021
10.71 (1.78 to 19.64)
0.019
Pulse pressure
24-h
0.040 (−0.049 to 0.129)
0.38
0.016 (−0.073 to 0.105)
0.72
3.07 (−5.99 to 12.13)
0.50
1.31 (−7.76 to 10.38)
0.77
Awake
0.048 (−0.041 to 0.137)
0.29
0.012 (−0.077 to 0.101)
0.78
3.63 (−5.43 to 12.68)
0.43
0.68 (−8.40 to 9.74)
0.88
Asleep
0.001 (−0.091 to 0.088)
0.98
0.001 (−0.087 to 0.090)
0.98
−0.29 (−9.37 to 8.78)
0.95
0.21 (−8.86 to 9.28)
0.96
ECG refers to electrocardiography. BP stands for blood pressure. Cornell voltage is the voltage sum of S wave in precordial V3 lead (SV3) and R wave in limb aVL lead (ReVL), while Cornell index is the product of QRS duration multiplied by the Cornell voltage. The estimate (95% Confidence Interval, CI) of the association was unadjusted and expressed as 1-SD increase of BP. P value is for significance of the estimate. The association estimates of Cornell voltage (P ≥ 0.054) and index (P ≥ 0.079) with central BP were not significantly different from those estimates with peripheral measurements.
TableAssociation of ECG Cornell voltage and indexes with peripheral and central BP.
Conclusions: The diurnal rhythm of peripheral and central BP run in parallel. Central BP does not improve the association of Cornell voltage or index with peripheral BP.
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