Accuracy of Cardiac Arrhythmias and Conduction Disorders Diagnosis Using Smartwatch in Comparison to Conventional Electrocardiogram in Patients With Cardiovascular Disease

The main objective of this study is to analyze, in patients with cardiovascular disease, the electrocardiographic aspects detected from the smartwatch device in comparison to the conventional electrocardiogram, identifying aspects of similarity between the tracings obtained and automatic diagnostic accuracy by the device and by visual assessment. of the layout. The secondary objectives will be to evaluate in the same population: aspects of practicality for the use of smart watches in clinical practice in cardiology; the success rate in obtaining the electrocardiographic tracing with adequate quality by the smart watch and describe the types of failure and assess the clinical characteristics related to the failure in obtaining the electrocardiographic tracing by the smart watch. Method: An observational, transversal, study of diagnostic accuracy will be carried out at the University Hospital of the Federal University of Piaui.

The sample size was calculated using MedCalc Statistical Software version 19.2.3 (MedCalc Software Ltd, Ostend, Belgium). For the sample calculation, the following parameters were considered: significance level of 95%, test power of 80%, value of the disease diagnosis rate of 84%, area under the receiver operating characteristic curve of 94% and equal proportion of number of positive and negative cases. The minimum sample size consisted of 100 patients, and an additional 10% will be added to compensate for possible losses. A total of 110 patients will be invited to participate in the study. Inclusion criteria: • Age ≥ 18 years;

• Patients followed up in the cardiology sector, hospitalized or outpatient, with the presence of one or more of the following diagnoses: systemic arterial hypertension, heart failure, valve disease, coronary atherosclerotic disease, myocardial infarction, endocarditis, myocarditis, diabetes, cardiac arrhythmias and patients with cardiac pacemakers or implantable automatic defibrillators. Exclusion criteria: • Patients who have electrocardiographic tracings, whether obtained from the watch or the conventional method, of poor quality that make it impossible or that makes the diagnosis difficult due to the technical aspect of the performance. • Withdrawal of the consent form at the request of the patient or guardian. Primary outcome: • Positive diagnostic correlation of the data obtained in group 1 (clock) in relation to group 2 (conventional ECG 12 leads and DI - single lead). Secondary outcome: • Successful verification of the electrocardiographic record by the watch; • Diagnostic accuracy of atrial fibrillation; • Diagnostic accuracy of heart rhythm disorders, excluding atrial fibrillation. Ethical aspects: All patients will be informed about the principles and objectives of the protocol before inclusion in the study and will be given explanations of potential advantages or disadvantages. All procedures involved in this study will be in accordance with the Helsinki Declaration of 1975, updated in 2013. The study will follow the principles of good clinical practice and the terms of Resolution No. 466/12 of December 12, 2012 of the National Health Council Ministry of Health. All patients or legal guardians will sign the informed consent form in writing before selection. Patients will be guaranteed that early withdrawal from the study will always be possible, without any consequence or impairment in their subsequent medical care. Data will be collected only after approval by the ethics and research committee. Those who do not sign the Informed Consent will not be included. Data collect The variables analyzed will be: clinical-demographic data of the patients, including age, sex, race, socioeconomic profile; comorbidities and electrocardiographic findings as measured by the clock and conventional ECG. The data will be analyzed comparatively between the groups: 1 = ECG on the clock; 2 = 12-lead conventional ECG and DI (single lead).

Electrocardiographic recording devices The smart watch used will be the Apple Watch series 4, from Apple Inc. (Specifications: Sensor I, 511 Hz, mobile operating system 13.1.3, operating system 6.0.1, Watch 4.2). For the recording of the conventional electrocardiogram, a mobile device will be used that allows the recording of 12 simultaneous leads and the rhythm tracing of the DI lead.

Criteria for electrocardiographic diagnosis The criteria for electrocardiographic diagnosis of morphological aspects, intervals and conclusive report will be based on the guideline of the Brazilian Society of Cardiology on the analysis and issuance of electrocardiographic reports.