Regenerating Heart Tissue with Nanotube Patches

Each year, over 780,000 Americans suffer from a second heart attack as a result of previously damaged cardiac muscle.  Because of this, repairing or regenerating new tissue has been a focus of researchers from a wide array of disciplines. 

Nanotube patch technology is a combination of carbon nanofibers and polymers.  Combined, they are designed to help encourage cell growth.  The technology is based on two concepts.  First, the nano structures are similar in size to a cell, thus allowing for the interaction between the two and limiting the chance for rejection.  Additionally, the patch acts as a scaffold, allowing stem cells or other forms of therapy to be held in place long enough for the tissue to grow.

Lab tests have shown that nerve cells have also responded to the therapy.  It is an important concept considering electrical conductivity is a key function of a cardiac muscle cell.  Early studies have shown that the combination of carbon nanofibers and polymers led to five times as many heart tissue cells growing on the surface than with only the polymer.  Furthermore, the density of cell doubled after just four days.

Early designs allow for the flexible patch to be delivered in the cath lab or with a needle.  This will benefit already compromised patients that would be at risk from a surgical procedure.  Although it may be several years before the nanopatch enters the market, just think of the savings and improved outcomes.  The promise is enormous!

Wow!  It’s nothing short of revolutionary to combine bioelectromagnetism with acoustics.  The result is an ultrasound device that’s safer than a CT and can provide images that approach MRI quality.  This isn’t the first time I have written on a form of acoustic imaging, and every time I come back to it, it gets better.  Its excellent ability to distinguish between malignant and benign lesions at a fraction of the costs of higher-end systems makes it an exciting topic.

Because dissimilar tissues react differently to outside stimuli, each layer will vibrate at its own unique frequency when stimulated.  This can be measured and converted into an image by means of ultrasound detectors.  Researchers have used light, ultrasound, and RF energy for stimulating, and the results from RF or microwave energy (electromagnetic) have been very exciting. 

Cancerous tissue is 50 times more electrically conductive than normal tissue, and RF energy also has the ability to penetrate much deeper into the body than light.  This makes electromagnetic acoustic imaging an excellent technology for diagnosing a whole range of tumors despite their location.

However, many wonder: how safe is RF or microwave energy when used on humans?  It is the same form of energy used for radar and cooking.  Studies have shown that the low level of electromagnetic energy required for the body is safe on human tissues.  Researchers have also demonstrated the technology’s ability to detect and localize tumors as small as 2 mm in diameter.

Electromagnetic Acoustic Imaging – Next-Generation Ultrasound

Wow! It’s nothing short of revolutionary to combine bioelectromagnetism with acoustics. The result is an ultrasound device that’s safer than a CT and can provide images that approach MRI quality. This isn’t the first time I have written on a form of acoustic imaging, and every time I come back to it, it gets better. Its excellent ability to distinguish between malignant and benign lesions at a fraction of the costs of higher-end systems makes it an exciting topic.

Because dissimilar tissues react differently to outside stimuli, each layer will vibrate at its own unique frequency when stimulated. This can be measured and converted into an image by means of ultrasound detectors. Researchers have used light, ultrasound, and RF energy for stimulating, and the results from RF or microwave energy (electromagnetic) have been very exciting.

Cancerous tissue is 50 times more electrically conductive than normal tissue, and RF energy also has the ability to penetrate much deeper into the body than light. This makes electromagnetic acoustic imaging an excellent technology for diagnosing a whole range of tumors despite their location.

However, many wonder: how safe is RF or microwave energy when used on humans? It is the same form of energy used for radar and cooking. Studies have shown that the low level of electromagnetic energy required for the body is safe on human tissues. Researchers have also demonstrated the technology’s ability to detect and localize tumors as small as 2 mm in diameter.

Time-Reversed Ultrasound

Ultrasound technology has evolved to view just about every area of the body but it still has its limitations in efficiently penetrate varying tissues, which has limited ultrasound’s ability to treat and image critical areas of the body such as the brain, liver, and heart.  But, time-reversed ultrasound is an emerging technology designed to improve the accuracy of both imaging and therapeutic ultrasound technology. 

Time-reversal captures and records a sound wave.  The wave is then compressed and stored in a database, and then sent back in the opposite order it was received.  So, it is sent back to its exact origin but at a much higher power.  This allows it to be very accurate through multiple tissue layers while producing a highly focused sound wave that requires less power to generate. 

Focused ultrasound as a therapy has been approved since 2004 for treatment for uterine fibroids.  Although highly successful in soft tissue applications, it has limited accuracy when passing through bone or open body cavities.  Transcranial focused ultrasound surgery, an emerging technology for treating brain tumors, has realized the benefits of time-reversal technology.  In fact, one study found that refocusing the ultrasonic beam at the target improved the error to lower than 0.7 mm.

I had asked Dr. Emad S. Ebbini, Ph.D., biomedical researcher and associate professor at the University of Minnesota in Minneapolis, Minn., about the applications of Time Reversal technology and he noted, “Overall, time-reversal acoustics will be used to improve ultrasound technology.  With the time-reversal technique, you can correct for tissue aberrations and refocus the ultrasound wave to make it more accurate.  This overcomes the problem when you focus ultrasound through different types of tissue,”

Ultrasound is an amazing technology; it provides excellent image quality while being safe to both the operator and patient.  This and new handheld technology are two primary factors in driving a market that is expected to reach $1.4 billion by 2014.  When time-reversal acoustics becomes available, ultrasound will play a much larger role in the therapy market.

Growing a Broken Heart

The heart is an amazing device in itself but has one major drawback: once damaged, it has a limited ability to repair itself.  So, calling the use of your own cells to repair damaged heart tissue “groundbreaking” is an understatement! 

However, Dr. Warren Sherman, MD, FACC, FSCAI Director, Cardiac Cell-Based Endovascular Therapies Center for Interventional Vascular Therapy, Columbia University Medical Center, is a leading authority on autologous cell therapy and explained its potential to me.  He stated, “We’re looking at cell therapy for the treatment of heart muscle disease after it’s been damaged, meaning weeks, months, or years after it’s been damaged.  For patients with congestive heart failure, the impact could be huge.”

Autologous cell therapy is a process that uses a patient’s own cells to repair the damaged myocardium and consists of several steps.  The first step involves obtaining adult stem cells through a muscle biopsy of the patient’s thigh.  Next, the cells are cultured in a lab to separate immature cells; finally, millions of cells are implanted in the heart tissue by either an open or percutaneous, minimally invasive procedure using the femoral artery. 

There have been multiple clinical trials focused on when and where in the heart tissue to deliver the cell therapy.  These studies have shown that the timing of cell delivery after AMI (acute myocardial infarction) may be one of the most important criteria in determining the efficacy of the therapy.  When delivering in a one to seven day time frame, patients experienced LVEF (left ventricular ejection fraction) improvement by 6 to 9%.  Delivery of the cells up to three months after a MI enabled a 3 to 5% improved LVEF.

Considering what it takes to treat the 5 million Americans suffering from congestive heart failure, this could be nothing short of revolutionary.  Over 300,000 patients per year will never fully recover from a heart attack, and the Business Group on Health reports that the average cost of treating these patients starts at $1 million.  The routine use of autologous cell therapy is still several years away, but its potential impact already has people excited.