Cardiovascular screening in low-income settings using a novel 4-lead smartphone-based electrocardiograph (D-Heart®).

BACKGROUND: MHealth technologies are revolutionizing cardiovascular medicine. However, a low-cost, user-friendly smartphone-based electrocardiograph is still lacking. D-Heart® is a portable device that enables the acquisition of the ECG on multiple leads which streams via Bluetooth to any smartphone. Because of the potential impact of this technology in low-income settings, we determined the accuracy of D-Heart® tracings in the stratification of ECG morphological abnormalities, compared with 12-lead ECGs.

METHODS: Consecutive African patients referred to the Ziguinchor Regional Hospital (Senegal) were enrolled (n=117; 69 males, age 39±11years). D-Heart® recordings (3 peripheral leads plus V5) were obtained immediately followed by 12 lead ECGs and were assessed blindly by 2 independent observers. Global burden of ECG abnormalities was defined by a semi-quantitative score based on the sum of 9 criteria, identifying four classes of increasing severity.

RESULTS: D-Heart® and 12-lead ECG tracings were respectively classified as: normal: 72 (61%) vs 69 (59%); mildly abnormal: 42 (36%) vs 45 (38%); moderately abnormal: 3 (3%) vs 3 (3%). None had markedly abnormal tracings. Cohen's weighted kappa (kw) test demonstrated a concordance of 0,952 (p<0,001, agreement 98,72%). Concordance was high as well for the Romhilt-Estes score (kw=0,893; p<0,001 agreement 97,35%). PR and QRS intervals comparison with Bland-Altman method showed good accuracy for D-Heart® measurements (95% limit of agreement ±20ms for PR and ±10ms for QRS).

CONCLUSIONS: D-Heart® proved effective and accurate stratification of ECG abnormalities comparable to the 12-lead electrocardiographs, thereby opening new perspectives for low-cost community cardiovascular screening programs in low-income settings.