Author + information
- Stephanie Hakimiana,b,
- Mahdi Esfahaniana,b,
- Kale Kaustubha,b,
- Elie Donatha,b,
- Steven Borzaka,b and
- Robert Chaita,b
Background: Cardiac time intervals (CTI) have been classically obtained with phonocardiography, though this technique has been overlooked since the advent of the 2D M-mode echocardiography. The “HemoTag” is a new technology that uses heart sounds and an ECG signal transduced via 3 thoracic electrodes to measure CTI and can potentially constitute a quick and cost effective means of assessing presence or absence and severity of pulmonary hypertension in patients. “HemoTag” indices were assessed as a marker of pulmonary artery systolic pressure using peak tricuspid regurgitation velocity as established echocardiographic measures of pulmonary hypertension, using a variety of prediction models.
Methods: 103 consecutive patients were recruited at an outpatient cardiology clinic from March and September 2016. CTI measurements were obtained for all patients using both conventional echocardiography and via “HemoTag”. EMAT (electro-mechanical activation time) was evaluated for correlation with tricuspid regurgitation peak velocity (TRmax mmHg) with use of the modified Bernoulli equation (Δp = 4V2).
Results: The female to male ratio was 0.91 and the mean age was 69.83 +/- 15.60 years. The mean systolic blood pressure was 129.36 +/- 20.85 mmHg; and mean weight 179.32 +/- 49.15 pounds. With a linear regression-based prediction model, a sensitivity of 72.73%, specificity of 82.61% and accuracy of 81.25% was noted. With a support vector machine (SVM)-based prediction model, a sensitivity of 90.9%, specificity of 85.51% and accuracy of 86.25% was noted. Patients were then randomly allocated into two subsets – one to drive the model and the other to validate it. Using a logistic regression, an ROC curve was employed to assess performance with an AUC of 0.83 in the validation set.
Conclusion: “HemoTag” represents a cost effective and potentially widely applicable technology for the assessment of EMAT, which seems to correlate with TRmax and thus pulmonary hypertension. Larger studies are needed to reinforce the conclusions stated above.
Poster Hall, Hall C
Friday, March 17, 2017, 10:00 a.m.-10:45 a.m.
Session Title: Imaging Pulmonary Vascular Disease Plus the Impact of Congenital Heart Disease
Abstract Category: 35. Pulmonary Hypertension and Pulmonary Thrombo-embolic Disease
Presentation Number: 1100-004
- 2017 American College of Cardiology Foundation