Diagnostic sensitivity of a smartphone-based electrocardiographic monitoring system in patients with ST elevated myocardial infarction

Abstract

Introduction and objectivesThe pocket sized KardiaMobile (KM) is a monitoring device for ECG recording through a smartphone-based application. This system is generally aimed as screening tool to detect alterations in cardiac rhythm but its diagnostic potential for detection of ST changes remains largely unknown. This study sought to assess the diagnostic sensitivity of the KM system for detection of ST changes in patients with ST elevated myocardial infarction (STEMI). MethodsPatients admitted with diagnosis of STEMI were consecutively included. Recordings with KM were obtained in leads I, II and anterior precordial. KM recordings were obtained as well from healthy individuals. All recordings were submitted for blinded assessment. ResultsA total of 112 patients with STEMI and 25 healthy individuals were included. Among those showing ST changes, these consisted mostly in depression (75%). Sensitivity was modest for individual leads (57-58%). The combination of 2-leads, when including the precordial, and the combination of 3-leads markedly increased sensitivity (88-98% and 100% respectively) for both inferior and anterior STEMI. Specificity was very high (96-100%) and the Youden's J statistic was excellent for the 2-leads combinations that included the precordial lead (0.84-0.94) and for the 3-leads combination (0.96). ConclusionsThe Kardia Mobile system with the combination of 2-leads (I+precordial or II+precordial) or 3-leads shows a very high sensitivity for both anterior and inferior STEMI.