ST Elevation Myocardial Infarction Hemodynamic OutComes: Role of Non-Invasive Cardiac System (SHOCk-NICaS) Study

Proposed novel solution for high-risk heart disease Overall in-hospital mortality among ST elevation myocardial infarction (STEMI) patients is 3-4%, but >50% patients experiencing cardiogenic shock (CS) secondary to STEMI die in the hospital. Evidence suggests early diagnosis and treatment of CS results in improved outcomes, albeit, there is no tool to diagnose CS reliably in a timely fashion in STEMI patients through the continuous monitoring. We hypothesize that bioimpedance-derived hemodynamic measures obtained using the Non-Invasive Cardiac System (NICaS) can facilitate early detection of CS, predict outcomes, and revolutionize the STEMI patient management. The objectives of SHOCk-NICaS study in STEMI patients are to: a) identify the CS early, using NICaS derived cardiac index of ≤1.8L/min/m2 or ≤2.2L/min/m2 with the use of vasopressor and/or inotropes, and compare it with the incidence of CS based upon lactate level ≥2mmol/L, and systolic blood pressure <90mmHg; b): determine the impact of primary percutaneous coronary intervention (PPCI), using NICaS derived hemodynamic measures (stroke volume, cardiac index, cardiac power index, etc), by comparing pre- and post-angioplasty; and c) identify outcome-associated hemodynamic markers. A composite score of death during hospital stay, prolonged hospitalization due to heart failure (>72hrs), and use of inotropic or mechanical circulation support is a primary outcome.

Methodology This is a multi-center, double-blind, prospective cohort study enrolling STEMI patients aged ≥18years visiting at 4 cardiac centers (St Boniface, St. Michael's, McGill University Hospital). Using validated NICaS protocol, hemodynamic parameters will be recorded at baseline, during the PPCI procedure, and within 24-hour post PPCI without altering the standard care. Statistical analysis: Baseline data will be reported as mean±SD or median±interquartile range. The outcomes will be assessed using multivariable logistic regression. We will analyze the impact of age, sex, gender, and ethnicity on hemodynamic measures. The targeted 500 patients will ensure a margin of error of 5% at a 95% CI. So far recruited 76 STEMI patients mark the study feasibility.

Significance This novel study in high-risk STEMI patients will provide a promising cost-effective, rapid, and non-invasive tool to identify CS early; a prompt intervention may curtail the high morbidity and mortality. The meticulously designed pragmatic study outcomes may revolutionize STEMI patient management.