Arterial pressure changes monitoring with a new precordial noninvasive sensor.
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ABSTRACT: Background
Recently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2) amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes.Methods
The transcutaneous force sensor was positioned in the precordial region in 146 consecutive patients referred for exercise (n = 99), dipyridamole (n = 41), or pacing stress (n = 6). The curve of S2 peak amplitude variation as a function of heart rate was computed as the increment with respect to the resting value.Results
A consistent S2 signal was obtained in all patients. Baseline S2 was 7.2 +/- 3.3 mg, increasing to 12.7 +/- 7.7 mg at peak stress. S2 percentage increase was + 133 +/- 104% in the 99 exercise, + 2 +/- 22% in the 41 dipyridamole, and + 31 +/- 27% in the 6 pacing patients (p < 0.05). Significant determinants of S2 amplitude were blood pressure, heart rate, and cardiac index with best correlation (R = .57) for mean pressure.Conclusion
S2 recording quantitatively documents systemic pressure changes.
SUBMITTER: Bombardini T
PROVIDER: S-EPMC2531180 | biostudies-literature | 2008 Aug
REPOSITORIES: biostudies-literature
Publications
Arterial pressure changes monitoring with a new precordial noninvasive sensor.
Bombardini Tonino T Gemignani Vincenzo V Bianchini Elisabetta E Venneri Lucia L Petersen Christina C Pasanisi Emilio E Pratali Lorenza L Pianelli Mascia M Faita Francesco F Giannoni Massimo M Arpesella Giorgio G Picano Eugenio E
Cardiovascular ultrasound 20080821
<h4>Background</h4>Recently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2) amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes.<h4>Methods</h4>The transcutaneous force sensor was positioned in the precordial re ...[more]
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