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Accuracy of pulse interval timing in ambulatory blood pressure measurement

View Article: PubMed Central - PubMed

ABSTRACT

Blood pressure (BP) monitors rely on pulse detection. Some blood pressure monitors use pulse timings to analyse pulse interval variability for arrhythmia screening, but this assumes that the pulse interval timings detected from BP cuffs are accurate compared with RR intervals derived from ECG. In this study we compared the accuracy of pulse intervals detected using an ambulatory blood pressure monitor (ABPM) with single lead ECG. Twenty participants wore an ABPM for three hours and a data logger which synchronously measured cuff pressure and ECG. RR intervals were compared with corresponding intervals derived from the cuff pressure tracings using three different pulse landmarks. Linear mixed effects models were used to assess differences between ECG and cuff pressure timings and to investigate the effect of potential covariates. In addition, the maximum number of successive oscillometric beats detectable in a measurement was assessed. From 243 BP measurements, the landmark at the foot of the oscillometric pulse was found to be associated with fewest covariates and had a random error of 9.5 ms. 99% of the cuff pressure recordings had more than 10 successive detectable oscillometric beats. RR intervals can be accurately estimated using an ABPM.

No MeSH data available.


Distribution of ΔRRFP for each participant.The boxes denote the inter-quartile range (IQR, upper: Q3, lower: Q1) of the data, the upper and lower whiskers are defined as min (max(ΔRRFP), Q3 + 1.5*IQR) and max (min(ΔRRFP), Q1-1.5*IQR) respectively. Outliers are any points outside of this range.
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f5: Distribution of ΔRRFP for each participant.The boxes denote the inter-quartile range (IQR, upper: Q3, lower: Q1) of the data, the upper and lower whiskers are defined as min (max(ΔRRFP), Q3 + 1.5*IQR) and max (min(ΔRRFP), Q1-1.5*IQR) respectively. Outliers are any points outside of this range.

Mentions: A summary of the results for the mixed effects models is given in Table 1. QQ plots and univariate plots for the models are given in supplementary Figures S1–S3. Age, MAP and RR interval were centred to the median values for the population (34 years, 90 mmHg and 912 ms respectively). The sizes of the random effects due to participant number and measurement order were small (less than 10−6 ms). This indicates that the between-participant variability is not significantly larger than the within-subject variability in the response as suggested by Fig. 5 for the FP case.


Accuracy of pulse interval timing in ambulatory blood pressure measurement
Distribution of ΔRRFP for each participant.The boxes denote the inter-quartile range (IQR, upper: Q3, lower: Q1) of the data, the upper and lower whiskers are defined as min (max(ΔRRFP), Q3 + 1.5*IQR) and max (min(ΔRRFP), Q1-1.5*IQR) respectively. Outliers are any points outside of this range.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5120306&req=5

f5: Distribution of ΔRRFP for each participant.The boxes denote the inter-quartile range (IQR, upper: Q3, lower: Q1) of the data, the upper and lower whiskers are defined as min (max(ΔRRFP), Q3 + 1.5*IQR) and max (min(ΔRRFP), Q1-1.5*IQR) respectively. Outliers are any points outside of this range.
Mentions: A summary of the results for the mixed effects models is given in Table 1. QQ plots and univariate plots for the models are given in supplementary Figures S1–S3. Age, MAP and RR interval were centred to the median values for the population (34 years, 90 mmHg and 912 ms respectively). The sizes of the random effects due to participant number and measurement order were small (less than 10−6 ms). This indicates that the between-participant variability is not significantly larger than the within-subject variability in the response as suggested by Fig. 5 for the FP case.

View Article: PubMed Central - PubMed

ABSTRACT

Blood pressure (BP) monitors rely on pulse detection. Some blood pressure monitors use pulse timings to analyse pulse interval variability for arrhythmia screening, but this assumes that the pulse interval timings detected from BP cuffs are accurate compared with RR intervals derived from ECG. In this study we compared the accuracy of pulse intervals detected using an ambulatory blood pressure monitor (ABPM) with single lead ECG. Twenty participants wore an ABPM for three hours and a data logger which synchronously measured cuff pressure and ECG. RR intervals were compared with corresponding intervals derived from the cuff pressure tracings using three different pulse landmarks. Linear mixed effects models were used to assess differences between ECG and cuff pressure timings and to investigate the effect of potential covariates. In addition, the maximum number of successive oscillometric beats detectable in a measurement was assessed. From 243 BP measurements, the landmark at the foot of the oscillometric pulse was found to be associated with fewest covariates and had a random error of 9.5 ms. 99% of the cuff pressure recordings had more than 10 successive detectable oscillometric beats. RR intervals can be accurately estimated using an ABPM.

No MeSH data available.