Congestive Heart Failure
- Last Updated: February 17, 2017
Over 650,000 people in the US are diagnosed with congestive heart failure (CHF) each year, and it is the leading cause of hospitalization for people over 65. In CHF, the heart is weakened and pumps blood at a reduced rate. The heart's response can be to stretch (to try to pump more blood) or to increase its muscle mass (to generate more pressure). Both responses result in a heart that is less efficient and has higher demand for oxygen and nutrients. External signs of CHF can be retained fluid, especially in the legs, ankles, arms, and lungs.
The challenge of current treatment is truly an optimization of the medications, as the right balance is required. For example, your heart needs an adequate supply of blood, but an oversupply that results in an over expanded heart. Control of blood pressure needs to be high enough to adequately supply nutrients and oxygen to your heart, but not so high that the heart has to work harder to pump against the higher blood pressure. There is a scale for the disease and symptoms that has some recommendations for drug therapy to help balance the treatment options.
An additional part of the challenge is to make sure that there are no mechanical obstructions to perfusion of the heart that can be treated with stents or bypass surgery.
Focused Ultrasound Research
There are some early approaches to explore focused ultrasound's role in managing congestive heart failure. Part of the challenge is that the balance of various factors is required. This can make any intervention, including those with focused ultrasound, difficult to achieve.
One early, pre-clinical project is looking at the period after an infarction and uses focused ultrasound to shrink the size of the infarcted region. The goal is to achieve the right amount of tissue reduction to offset the post-myocardial tissue expansion that is typically seen. This project is in progress, and we will report the results when they are available. More research is needed prior to clinical trials.
Laughner JI, Sulkin MS, Wu Z, Deng CX, Efimov IR. Three potential mechanisms for failure of high intensity focused ultrasound ablation in cardiac tissue. Circ Arrhythm Electrophysiol. 2012 Apr;5(2):409-16. doi: 10.1161/CIRCEP.111.967216.
Otsuka R, Fujikura K, Abe Y, Okajima K, Pulerwitz T, Engel DJ, Muratore R, Ketterling JA, Kalisz A, Sciacca R, Marboe C, Yi G, Wang J, Homma S. Extracardiac ablation of the left ventricular septum in beating canine hearts using high-intensity focused ultrasound. J Am Soc Echocardiogr. 2007 Dec;20(12):1400-6.
Yin X, Epstein LM, Hynynen K. Noninvasive transesophageal cardiac thermal ablation using a 2-D focused, ultrasound phased array: a simulation study. IEEE Trans Ultrason Ferroelectr Freq Control. 2006 Jun;53(6):1138-49.