Treatable vs Untreatable Sudden Cardiac Arrest: A new clinical algorithm can find the difference

Sudden cardiac arrests can be fatal, and triggering within minutes can cause life-threatening situations, including death. Certain forms of cardiac arrests can be treatable when acted on time. Clinicians and Scientists in the Smidt Heart Institute developed a clinical algorithm, for the first time, that distinguishes between treatable sudden cardiac arrest and untreatable forms of this condition.

With almost 3,00,00 lives claimed due to cardiac arrests in the U.S, it is observed that 10 minutes post-cardiac arrest is crucial to prevent fatal outcomes of this condition. Published in the peer-reviewed Journal of the American College of Cardiology: Clinical Electrophysiology, the study findings by Dr. Sumeet Chugh et al., show the potential to improve the prevention of sudden cardiac arrest and unexpected loss of heart function based on key risk factors.

The study: How the new clinical algorithm designed can make a difference?

All cardiac arrests are not the same. With potentially treatable certainties, sudden cardiac deaths manifest as ventricular fibrillation (VF) and ventricular tachycardia (VT), potentially treatable with defibrillation or non-shockable rhythms- pulseless electrical activity with minimum likelihood of survival. Though defibrillators are expensive and may not benefit individuals with certain manifestations of cardiac arrests, they can be a potent life-saver for treatable forms of this condition. 

The biggest challenge of the study was distinguishing between those who stand to benefit the most from an implantable cardioverter-defibrillator and those who do not benefit from the electric shock. 

The research included the data from two ongoing multi-year studies by Dr. Chugh. The ongoing studies gave researchers community-based information that could help determine ways to predict sudden cardiac arrests. Based on the statistical data, Dr. Chugh and his team conducted future risk assessment testing as a part of prospective studies for randomized clinical trials. 

The clinical assessment of the study was constructed with 13 clinical, electrocardiogram (ECG), echocardiographic variables that could put the patient at the risk of a sudden treatable cardiac arrest like- diabetes, myocardial infarction, heart failures, atrial fibrillation, stroke, pulmonary disorders, sudden fall in blood pressure, and seizures. 

The first-of-its-kind algorithm showed potential improvement in predicting the possibility of a sudden cardiac arrest using widely available clinical and non-invasive markers, especially in patients with mid-range or preserved left ventricular ejection fraction (LVEF). 

Sumeet Chugh, MD, director of the Center for Cardiac Arrest Prevention, also a professor and the Pauline and Harold Price Chair in Cardiac Electrophysiology Research, the lead author of the study says, “This new research provides a clinical risk assessment algorithm that can better identify patients at highest risk of treatable sudden cardiac arrest, and thus, a better understanding of those patients who would benefit from a defibrillator.”