Novel Approach to Assess Cardiac Function Using Systolic Performance and Myocardial Performance Indices From Simultaneous Electrocardiography and Phonocardiography Recordings in Dogs With Various Stages of Myxomatous Mitral Valve Disease

Abstract

Background and Objective: Myxomatous mitral valve disease (MMVD) progression entails changes in the structural and functional properties of the heart affecting cardiac timings and intervals within the cardiac cycle. Conventionally, echocardiography is used to determine the cardiac time intervals (CTIs) including systolic and myocardial performance indices (SPI and MPI) in evaluating cardiac function. Alternatively, these CTIs can also be measured using simultaneous recordings of electrocardiography (ECG) and phonocardiography (PCG), but their values in different MMVD stages remain to be established. This study aimed to establish and prove the use of derived SPI and MPI from a dedicated device as a novel approach to assess cardiac function in different stages of MMVD dogs.Materials and Methods: A prospective study in 52 dogs with different MMVD stages measured the CTIs using a novel device. These were compared and correlated with standard echocardiographic parameters. The predictive value of SPI and three new proposed formulas to estimate MPI (i.e., F1, F2, and F3) in association with asymptomatic from symptomatic MMVD dogs were investigated.Results: Our findings revealed that CTI parameters measured from a novel device including QS1, QS2, S1S2, MPI-F1, and MPI-F2 were altered at different stages of MMVD. The SPI and all proposed MPI formulas were comparable with the systolic time interval and Tei index from echocardiography. In addition, the SPI, MPI-F1, and MPI-F2 were significantly correlated with the Tei index. However, the SPI was not able to differentiate the various stages of MMVD. Conversely, only the MPI-F1 (i.e., (QS1 + S2)/S1S2) demonstrated good predictive accuracy when compared between asymptomatic and symptomatic MMVD dogs similar to the Tei index. Moreover, this formula was able to differentiate stages B1 and C with remarkable predictive accuracy, higher sensitivity, and high specificity when compared with the Tei index.Conclusion: We have successfully described the CTI parameters in different MMVD stages using simultaneous ECG and PCG recordings in dogs. Furthermore, we have proven that the concept of using the newly proposed parameters from a novel device is equivalent to the Tei index. Thus, we established a novel approach to evaluate cardiac function and its supportive use in the diagnosis of MMVD patients.

Use of proposed systolic and myocardial performance indices derived from simultaneous ECG and PCG recordings to assess cardiac function in healthy Beagles

“…We did not notice a similar study on healthy dogs. However, we previously reported the use of similar CTI parameters in MMVD dogs [37]. This study found that MPI-F1 may not be interchangeably used with the Tei index as it demonstrated a wide disagreement.…”

“…Moreover, the available commercial device measuring both ECG and PCG device ([The Eko DUO ECG + Digital Stethoscope; Eko DUO] Eko Devices Inc., California) is designed mainly for humans with proprietary algorithms and software. Recently, we reported the use of the Eko DUO device to determine CTIs and its feasibility in measuring cardiac function in MMVD dogs [37]. Nevertheless, the development of a novel device designed primarily for dogs can be a supportive tool in describing and evaluating cardiac functions, particularly in areas where STE is limited or inaccessible.…”

Evaluation of the association between electrocardiogram parameters and left cardiac remodeling in dogs with myxomatous mitral valve disease

“…However, the rate of change in the PR interval and R-wave amplitude over time improved the diagnostic ability for left cardiac remodeling. Although several studies have evaluated ECGs in dogs with MMVD in recent years [21,22], to the best of our knowledge, this is the first R-wave amplitude, and mean electrical axis.…”

Iron parameters analysis in dogs with myxomatous mitral valve disease

“…Many studies chose to combine groups C and D into a group of symptomatic dogs [ 29 ] or B1 and B2 as an asymptomatic group [ 30 , 31 ] for statistical analysis. The results obtained were also analyzed with a division into asymptomatic and symptomatic dogs [ 32 , 33 ], as in this article.…”