Devices, systems, and methods for cardiac resynchronization therapy

A wireless controller-transmitter for controlling stimulation of a left ventricle of a heart, the controller-transmitter comprising:

• one or more sensors configured to receive an indication of electrical conduction of the heart;
• a controller operably coupled to the one or more sensors and configured to determine, in substantially real-time, an occurrence of an onset of a QRS segment in the electrical conduction of the heart;
• and
• a transducer operably coupled to the controller and configured to emit an acoustic signal in response to the controller determining the occurrence of the onset of the QRS segment in the electrical conduction of the heart,
• wherein the transducer is configured to emit the acoustic signal toward a receiver-stimulator implanted within or adjacent the left ventricle to cause the receiver-stimulator to deliver electrical stimulation to the left ventricle within a predefined duration beginning at the onset of the QRS segment, and
• wherein emission of the acoustic signal is configured to improve contraction synchronization of the left ventricle and a right ventricle of the heart.

A method of controlling stimulation of a left ventricle of a heart of a human subject, the method comprising:

• sensing an initiation of an electrical signal to contract a right ventricle of the heart by detecting an onset of a QRS segment;
• and
• emitting acoustic energy in response to the sensed initiation of the electrical signal to contract the right ventricle,
• wherein the acoustic energy is directed toward a receiver-stimulator implanted within or adjacent the left ventricle, and
• wherein emitting the acoustic energy improves contraction synchronization of the left ventricle and a right ventricle of the heart by causing the receiver-stimulator to deliver electrical stimulation to the left ventricle.