Devices, systems, and methods for improving left ventricular structure and function using baroreflex activation therapy
Described here are devices, systems, and methods for improving left ventricular function in a patient with systolic heart failure with left ventricular dysfunction using baroreflex activation therapy. In general the systems have at least one electrode and a control system in communication with the electrode, the control system including a processor and memory, wherein the memory includes software defining a stimulus regime configured to effect improvement in left ventricular function. The methods for improving left ventricular function in a subject typically include identifying a patient in need of left ventricular function improvement and stimulating a baroreceptor with a baroreceptor activation device to improve left ventricular function.
1. A method for improving left ventricular function in a patient demonstrating symptoms of systolic heart failure with left ventricular dysfunction comprising:
identifying a patient in need of such improvement;
implanting a baroreflex activation device on a blood vessel, the blood vessel having a baroreceptor within its wall; and
activating a baroreflex in the patient to improve left ventricular function by electrically stimulating the baroreceptor using the baroreflex activation device.
2. The method of claim 1 , wherein the stimulation is pulsed.
3. The method of claim 1 , wherein the stimulation is continuous.
4. The method of claim 1 , wherein the baroreceptor is located in a vein.
5. The method of claim 4 , wherein the vein is selected from the group consisting of the inferior vena cava, the superior vena cava, the portal vein, the jugular vein, the subclavian vein, iliac vein, azygous vein, pulmonary vein, and femoral vein.
6. The method of claim 1 , wherein the baroreceptor is located in a carotid sinus, aortic arch, heart, common carotid artery, subclavian artery, pulmonary artery, femoral artery, or brachiocephalic artery.
7. The method of claim 1 , wherein improvement in left ventricular function is confirmed by a hemodynamic measurement.
8. The method of claim 7 , wherein the hemodynamic measurement is selected from the group consisting of left ventricular pressure, peak rate of change of left ventricular pressure during isovolumic contraction, left ventricular end-diastolic pressure, mean pulmonary artery pressure, mean pulmonary artery wedge pressure, mean right atrial pressure, cardiac output, left ventricular stroke volume, cardiac index, and combinations thereof.
9. The method of claim 1 , wherein improvement in left ventricular function is confirmed by an angiographic measurement.
10. The method of claim 9 , wherein the angiographic measurement is a left ventriculogram.
11. The method of claim 1 , wherein improvement in left ventricular function is confirmed by echocardiography and Doppler.
12. The method of claim 1 , wherein identifying a patient in need of left ventricular function improvement comprises identifying a patient having low ejection fraction, low cardiac output, increased end diastolic volume, ischemia, ventricular pump impairment, or combinations thereof.
13. The method of claim 1 , further comprising administering one or more active agents.
14. The method of claim 13 , wherein the active agent is selected from the group consisting of ACE inhibitors, diuretics, vasodilators, angiotensin II receptor blockers, beta-blockers, cardiac glycosides, anticoagulants, positive inotropic drugs, and combinations thereof.
15. The method of claim 1 , further comprising implanting one or more devices for improving left ventricular function.