As evidenced by the Framingham Heart Study, cardiologists know that heart rate variability (HRV) is a well-established marker of mortality and sudden death shown to be attenuated in patients with coronary artery disease (CAD) even at rest. Based on this clinical evidence, HeartTrends was developed to provide an innovative modality with a high sensitivity for detection of myocardial ischemia at rest.
The diagnostic yield of the HeartTrends test has now been established and reported in peer-reviewed journals ,. Clinical studies show HeartTrends sensitivity (77%) compared with standard exercise stress testing relating both to subsequent coronary angiography. The negative predictive value for ruling out myocardial ischemia was 98%. While your actual measurements may differ – and may even be lower-- HeartTrends offers a new, additional “risk factor” for enhanced patient diagnosis.
The heart rate of individuals displays beat-to-beat variations that result from fluctuations in autonomic nervous system activity at the sinus node. Heart rate variability (HRV) decreases under situations of stress, either emotional or physical, whereas it increases with rest. HRV is considered a noninvasive marker of autonomic nervous system function., Over the past decade, low HRV has been shown to have prognostic value in patients with myocardial infarction . In the general population low HRV is associated with death, and, as evidenced in the Framingham Heart Study, with the risk of cardiac events ,.
Several studies have shown that there is significant association between reduced HRV and incident coronary artery disease (CAD), suggesting that the imbalance of sympathetic and parasympathetic activity is associated with increased risk of CAD. These findings provide support for the hypothesis that correlates reduced parasympathetic activity to newly diagnosed CAD in the general population.
Recent clinical trial data indicates that the HRV analysis incorporated in the HeartTrends device is a highly sensitive, noninvasive tool that aids in the detection of myocardial ischemia in subjects without known prior CAD, thereby providing an important diagnostic tool and new independent cardiac risk factor for this population [9-13].
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 Clinical Trials.gov: US National Institute of Health (www.clinicaltrials.gov -- search for ‘HeartTrends’)