Abstract Body: Background: The emerging field of cardiac optogenetics uses pulses of light to stimulate optically-sensitive proteins in the heart, influencing cellular physiology with unprecedented spatiotemporal resolution. Effects include increased glutathione and carnosine activity, and promotion of ATP synthesis. Clinical benefits include improved functional capacity, heart rhythm stability, and relief form congestive heart failure (CHF). Transcutaneous phototherapy devices are now available (LifeWave Inc, San Diego, USA), which may provide these benefits without the requirement for an external power source.
Objective: To investigate whether upregulation of carnosine activity using a wearable cutaneous phototherapy device may improve echocardiographic measures of global heart function, cardiac contractility, and hemodynamics.
Methods: The Carnosine^® adhesive skin patch (34 mm outside diameter) contain an organic crystalline material that reflects back specific frequencies of infra-red light known to activate carnosine dipeptides throughout the body. These function as a high-energy phosphate system known to enhance muscle function. Study participants (n=12 healthy volunteers (7 male, 5 female), 40-66 years of age) underwent a focused baseline echocardiogram, which included atrial (A) and early (E) mitral valve inflow, peak tissue velocity (E’) at both the lateral and septal mitral annulus, and left ventricular ejection fraction (LVEF). 10-14 patches were then applied along the sternum and across the left thorax (3^rd-5^th interspace), incorporating the anterior axilla. The echocardiogram was repeated 20-30 minutes after patch application.
Results: LVEF was improved following application of the phototherapy device, increasing from 59.8±6.3% to 66.65±5.8% (Δ 6.3%, p<0.05), indicating an improvement in overall cardiac function. Septal E’ also increased, from 7.3±0.7 cm/s to 8.2±0.6 cm/s (Δ 0.89 cm/s, p<0.05), indicating a direct effect on contractility. E and A wave velocities increased from 63.7 cm/s to 66.1 cm/s (Δ 2.5±0.4 cm/s, p<0.08) and from 56.8 cm/s to 62.6 cm/s (Δ 5.7±0.7 cm/s, p<0.1), indicating augmented hemodynamics trending towards significance.
Conclusion: Self-powered wearable phototherapy devices may enhance myocardial contractility and overall cardiac function. Such technologies represent a promising therapy for CHF.