Cardiac acoustic biomarkers as surrogate markers to diagnose the phenotypes of pulmonary hypertension: an exploratory study

Nobuhide Yamakawa,Koichi Node,Norihiko Kotooka,Tatsuhiko Kuroda,Tomoyuki Kato

doi:10.1007/s00380-021-01943-7

Abstract

Pulmonary hypertension (PH) is commonly associated with left heart disease. In this retrospective study, using the database of a clinical study conducted between January 2008 and July 2008, the phenotypes of PH were classified using non-invasive cardiac acoustic biomarkers (CABs) and compared with classification by echocardiography. Records with same-day measurement of acoustic cardiography and right heart catheterization (RHC) parameters were included; cases with congenital heart disease were excluded. Using the RHC measurements, PH was classified as pre-capillary PH (Prec-PH), isolated post-capillary PH (Ipc-PH), and combined pre-capillary and post-capillary PH (Cpc-PH). The first, second, third, and fourth heart sounds (S1, S2, S3, and S4) were quantified as CABs (intensity, complexity, and strength). Forty subjects were selected: 5 had Prec-PH, 5 had Ipc-PH, 8 had Cpc-PH, and 22 had No-PH. CABs were significantly correlated with RHC measurements, with significant differences among phenotypes. Phenotype classification was performed using various CABs, and the diagnostic performance as assessed by the area under the receiver operating characteristic curve was 0.674–0.720 for Prec-PH, 0.657–0.807 for Ipc-PH, and 0.742 for Cpc-PH. High negative and low positive predictive values for phenotype identification were observed. CABs may provide an ambulatory measurement method with home-monitoring friendliness which is more convenient than standard examinations to identify presence of PH and its phenotypes.

Highlights

Pulmonary hypertension (PH) is commonly associated with left heart disease and categorized as PH due to left heart disease (PH-LHD) [1]
Significant correlations were observed between mean pulmonary artery pressure (PAP) and S2Complexity (V4) or S3Strength (V4), pulmonary artery wedge pressure (PAWP) and S3Intensity (V4) or S3Strength (3L, V4), pulmonary vascular resistance (PVR) and S2Complexity (3L, V4), and cardiac index (CI) and S1Intensity (3L) or S1Complexity (V4)
right heart catheterization (RHC) parameters and cardiac acoustic biomarkers (CABs) of the PH phenotypes are shown in Tables 3 and 4

Summary

Introduction

Pulmonary hypertension (PH) is commonly associated with left heart disease and categorized as PH due to left heart disease (PH-LHD) [1]. The majority of PH-LHD patients are reported to have heart failure (HF), with both reduced and preserved ejection fraction [2], which is a well-known pathological condition for functional and structural impairment in the heart [3]. The structure and hemodynamic status of the pulmonary circulation are largely affected by both pulmonary and cardiac failure, possibly leading to a poor prognosis due to remodeling in the right ventricle, as well as in the pulmonary artery and veins [4]. PH is mainly characterized by increased pulmonary artery pressure (PAP) on right heart catheterization (RHC) [6]. RHC provides precise information for PH diagnosis, and to differentiate PH phenotypes [pre-capillary PH (Prec-PH), isolated post-capillary PH (Ipc-PH), and combined pre- and post-capillary PH (Cpc-PH)] when other hemodynamic parameters, such as pulmonary artery wedge pressure (PAWP) and pulmonary vascular resistance (PVR), are available [7]. PAP has been a target of continuous monitoring for HF patients by an implantable device to decrease the risk of re-hospitalization [9], but no other

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Conclusion