Dear HeartLogic™ users,

In this issue we would like to deepen the correlation between HeartLogic algorithm and NT-proBNP biomarker for HF diagnosis.

You could find a brief summary about NT-proBNP and Heart Failure, a review of literature about HeartLogic and NT-proBNP, including the latest findings presented at Heart Failure Congresses, and a new case of the month.


NT-proBNP and Heart Failure



N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a non-active prohormone, produced by the heart and released in response to changes in pressure inside the heart. An increase in BNP or NT-proBNP levels occurs when heart failure develops or gets worse, and levels goes down when heart failure is stable.
In patients with heart failure, a high NT-proBNP level has been shown to be an independent predictor of in-hospital mortality, hospital readmission, lower life expectancy and stroke1.  Reviews of the role of the BNP and NT-proBNP suggest they have value in ruling out the presence of HF due to the high sensitivity of the tests. However, low specificity limits test usefulness for ruling-in HF2


NT-proBNP & HeartLogic:
data from MultiSENSE



Gardner et al3 presented a post hoc evaluation using results from the MultiSENSE study and the HeartLogic index.

A total of 900 patients were analyzed:

  • 145 HF events from 88 patients (0.20 events/pt-ys)
  • 456 patients (51%) experiences at least one HeartLogic alert
  • 120 patient –year IN ALERT state (17% of total patient-years follow-up)
A baseline NT-proBNP above a threshold of 1000 pg/ mL was associated with an event rate of 0.42 events/pt-yr, whereas below the threshold was associated with an event rate of 0.07 events/pt-yr, resulting in an event rate ratio of 6.0
NT-proBNP & HeartLogic: data from MultiSENSE
At the nominal threshold of 16, IN HeartLogic alert state was associated with an event rate of 0.80 events/pt-yr, whereas the OUT of alert state was associated with an event rate of 0.08 events/pt-yr, resulting in an event rate ratio of 10.6
NT-proBNP & HeartLogic: data from MultiSENSE
In the multivariable model, the event rate ratio for HeartLogic (at nominal threshold) remained significant (4.78; CI, 2.94–7.75; P<0.0001) and greater than the event rate ratios for the other variables (p<0.10 in univariate analysis) included NT-proBNP. This finding demonstrated that HeartLogic provides a measure of the risk of an HF event independent of baseline clinical variables.

Patients with HIGH baseline NT-proBNP when IN HeartLogic alert had a 50-fold higher event rate as compared to when patients with LOW baseline NT-proBNP when OUT of an alert state.

HeartLogic significantly augments the prognosis of a single snapshot NT-proBNP assessment at baseline for longer durations.

The main findings of this study are:

- HeartLogic identified patients at higher risk of an HF event independent of all baseline clinical measures, including NT-proBNP.

- HeartLogic significantly enhances the risk stratification offered by a single snapshot NT-proBNP during the following year.

Dynamic assessment using HeartLogic alerts either by itself or in conjunction with intermittent/sparse NT-proBNP can automatically identify periods of time in which patients are at significantly increased risk of worsening HF with the potential to better triage resources to this vulnerable patient population.


NT-proBNP & HeartLogic:
latest findings



A new analysis from MultiSENSE study about the use of HeartLogic and NT-proBNP has been presented at ESC-HF 2019 as Late Breaking Clinical Trials.

“HeartLogic Performs as Well as NT-proBNP to Rule Out Acute Heart Failure at Point of Care”
– Gardner et al.

The purpose of the analysis was to compare the diagnostic accuracy of NT-proBNP and HeartLogic to rule out acute decompensated HF (ADHF) in acute settings.

Of the total 603 hospitalizations only 76 (52 HF, 24 non-HF) had both valid NT-proBNP measures within 48 hours of admission (71 within 24 hours), and valid HeartLogic value for the day before the hospitalization date.

HeartLogic-based ROC was similar to the ROC of NT-proBNP (AUC of 0.809 and 0.803, respectively, p=0.932).

An exclusion criterion of HeartLogic index <1 achieved the same performance as an NT-proBNP<300pg/ml

  • When HeartLogic was <1 at admission (9 cases) or NT-proBNP <300 at admission (9), the adjudication was non-Heart Failure in 7 (0.778 NPV for both measures)
  • Of 52 hospitalizations adjudicated as heart failure, thresholds were exceeded for HeartLogic in 50 and NT-proBNP in 50 (sensitivity 0.962 for both measures)
  • Using either HeartLogic <1 or NT-proBNP < 300 at admission to rule out heart failure agreed with the adjudicated admission reason in 57 of 76 admissions (accuracy 75% for both measures)

The agreement between the two criteria was 84.2%.

Limiting the evaluation to 52 hospitalizations with acute dyspnoea (42 HF, 10 non-HF), the performance of HeartLogic and NT-proBNP were similar (p=0.906).

Expanding the evaluation of HeartLogic across all 467 hospitalizations with HeartLogic data (89 HF, 378 non-HF), performance was still similar (sensitivity 0.934, NPV 0.876 for the criterion of HeartLogic index <1; AUC of 0.734, p=0.166)

New data about the use of HeartLogic and NT-proBNP is going to be presented in the 2020 congresses... stay tuned!


Case of the month



A 74 year-old man underwent implantation of PERCIVA™ ICD VR for primary prevention of sudden cardiac death on February 21, 2019.

HeartLogic™ was activated on April 25, 2019, and physician became aware that…