SCA Screening: New Techniques for Identifying Patients at Risk

Background

Sudden cardiac arrest (SCA) is the leading cause of death in the United States. It is estimated that approximately 450,000 individuals die each year of this condition, which equates to 1,200 per day, 50 every hour, or one every 80 seconds. Mortality associated with SCA is larger than stroke, lung cancer, breast cancer, and AIDS combined. SCA is 95% fatal. Sudden cardiac arrest is the first presentation of cardiac disease in 20-25% of this defined population, though most occurrences (75-80%) occur in patients with recognized cardiac disease. According to the American Heart Association, individuals who have suffered a previous myocardial infarction have a sudden death rate that is 4-6 times higher than the general population. Reduced left ventricular ejection fraction (LVEF) remains the single most important risk factor for overall mortality and sudden cardiac death (Prior SG et al). Sudden cardiac death can be divided into three etiologies: 80% from coronary artery disease, 15% from cardiomyopathy, and 5% other (valvular, congenital, or ion-channel abnormalities). Literature clearly shows that early defibrillation is the key to survival. However, even with the best EMS programs, it is difficult to have high survival rates since many of the events are unwitnessed and it is difficult to reach the victim within 6-8 minutes. According to Swagemakers, 40% of SCAs are not witnessed or occur during sleep, and 80% of SCAs occur at home. In 1990, Dr. Roger White from the Mayo Clinic in Rochester, Minnesota approached the local police department and launched a study equipping police officers with semi-automatic defibrillators to see if the community could further improve patient outcomes. As a result, the survival rate is now estimated to be 43% as compared to 5% nationally. This shows the importance of early detection and defibrillation to survival.

SCA Campaign

On February 18th, 2008, Mayo Clinic initiated the Sudden Cardiac Arrest Awareness campaign. The goal of this program was to identify patients at risk for sudden cardiac arrest and to provide these patients with consultation discussing risk stratification and treatment options. From an operations perspective, the patients at risk were identified from screening patients undergoing LVEF measurements, which included echo, nuclear, and cath results. Reports were manually run from these databases utilizing reporting software, which identified patients with ejection fractions of Patient Screening Findings With one years’ worth of data, we now have a broader knowledge of the practice. We have discovered more patients going through our system with impaired ejection fractions than was previously estimated. Alerting physicians while the patient is hospitalized is an effective means to assure the critical discussion regarding SCA risk has taken place. This has also led to an improved awareness throughout the institution. We have witnessed an increase of 23% in new ICD implants as compared to the previous year along with an increased number of consultations through these efforts. Sending letters to physicians for patients undergoing clinical evaluation has been less effective, though. In an ideal practice, patients need to be screened daily in real time, in both the hospital and clinic settings, in order to capture all patients during their medical encounter. Patients post MI are not eligible for 40 days post infarct. For individuals who underwent stent, CABG, or have newly diagnosed non-ischemic cardiomyopathy, rescreening needs to take place in 90 days. We need to create a mechanism that reminds the screeners to assess the patient after these time periods.

Future Goals

The ultimate goal is to create tools that automate the screening process within the electronic medical record (EMR). This automated screening tool will screen discrete data elements imported from the echo, cath, nuclear, and MRI reports that are being sent into the EMR. When appropriate data elements and desired values are obtained from the EMR, the patient identified to be at risk will be relayed to the SCA coordinator through an inbox EMR message. This will allow the coordinator to act on the information daily while the patient is within the health care system. Screening tools will also be created to identify patients who have an ICD and/or have had the SCA discussion with their health care provider and have decided not to pursue ICD therapy.