Elgendi Mohamed, Bobhate Prashant, Jain Shreepal, Guo Long, Kumar Shine, Rutledge Jennifer, Coe Yashu, Zemp Roger, Schuurmans Dale, Adatia Ian
Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada ; Current address: Electrical and Computer Engineering in Medicine Group, University of British Columbia, and British Columbia Children's Hospital, Vancouver, British Columbia, Canada.
Department of Pediatrics and Pediatric Pulmonary Hypertension Service, Stollery Children's Hospital, University of Alberta, Edmonton, Alberta, Canada.
Pulm Circ. 2015 Dec;5(4):631-9. doi: 10.1086/683694.
We hypothesized that vibrations created by the pulmonary circulation would create sound like the vocal cords during speech and that subjects with pulmonary artery hypertension (PAH) might have a unique sound signature. We recorded heart sounds at the cardiac apex and the second left intercostal space (2LICS), using a digital stethoscope, from 27 subjects (12 males) with a median age of 7 years (range: 3 months-19 years) undergoing simultaneous cardiac catheterization. Thirteen subjects had mean pulmonary artery pressure (mPAp) < 25 mmHg (range: 8-24 mmHg). Fourteen subjects had mPAp ≥ 25 mmHg (range: 25-97 mmHg). We extracted the relative power of the frequency band, the entropy, and the energy of the sinusoid formants from the heart sounds. We applied linear discriminant analysis with leave-one-out cross validation to differentiate children with and without PAH. The significance of the results was determined with a t test and a rank-sum test. The entropy of the first sinusoid formant contained within an optimized window length of 2 seconds of the heart sounds recorded at the 2LICS was significantly lower in subjects with mPAp ≥ 25 mmHg relative to subjects with mPAp < 25 mmHg, with a sensitivity of 93% and specificity of 92%. The reduced entropy of the first sinusoid formant of the heart sounds in children with PAH suggests the existence of an organized pattern. The analysis of this pattern revealed a unique sound signature, which could be applied to a noninvasive method to diagnose PAH.
我们假设，肺循环产生的振动会产生类似于说话时声带发出的声音，并且肺动脉高压（PAH）患者可能具有独特的声音特征。我们使用数字听诊器，在心脏尖部和左第二肋间（2LICS）记录了27名受试者（12名男性）的心音，这些受试者年龄中位数为7岁（范围：3个月至19岁），同时进行心脏导管插入术。13名受试者的平均肺动脉压（mPAp）<25 mmHg（范围：8 - 24 mmHg）。14名受试者的mPAp≥25 mmHg（范围：25 - 97 mmHg）。我们从心音中提取了频段的相对功率、熵以及正弦共振峰的能量。我们应用留一法交叉验证的线性判别分析来区分有无PAH的儿童。结果的显著性通过t检验和秩和检验确定。在2LICS记录的、优化窗口长度为2秒的心音中，mPAp≥25 mmHg的受试者相对于mPAp < 25 mmHg的受试者，第一正弦共振峰的熵显著降低，灵敏度为93%，特异性为92%。PAH患儿心音中第一正弦共振峰熵的降低表明存在一种有组织的模式。对这种模式的分析揭示了一种独特的声音特征，可应用于一种无创诊断PAH的方法。
