By Dr. Gholam Mohammadzadeh
In July 2014, a significant heart-healthy milestone was reached at Los Robles Hospital. Instead of undergoing open-heart surgery to replace a defective aortic valve, two patients with severe aortic stenosis, were the first at the hospital to receive new aortic heart valves via a catheter in the femoral artery.
Aortic stenosis occurs when the aortic valve in the heart narrows and restricts the amount of blood flow to the body. This can cause chest pains, shortness of breath and even heart failure. About 7 percent of Americans over age 65 are afflicted with aortic stenosis.
Since the 1960s, treatment for aortic stenosis involved surgically opening the chest and then replacing the aortic valve. Success has been spectacular. Today, aortic valve replacement (AVR) carries a mortality rate as low as 2 percent and very low complication rates in most patients.
However, despite these monumental achievements, there remains a subgroup of patients where the physical trauma that is inherent to open chest surgery can have unacceptable and often fatal consequences. This concern led to a concerted effort since the 1990s to transform the operation from open chest to a catheter based technology.
In 2002, the first transcatheter valve replacement took place in France with the first successful implantation in the U.S. coming in 2005. The minimally invasive surgery is done through the femoral artery in the groin, leaving the chest bones in place. Initially, the new technology was plagued with alarmingly high rates of post-operative stroke. Since then, improvements in security features of the catheter devices used in the procedure have led to safer surgeries and a reduction in the numbers of post-operative complications.
In 2010 and 2011, The New England Journal of Medicine announced the findings of the “Partner Trials” that firmly established the safety and efficacy of Transcatheter Aortic Valve Replacement (TAVR) in the two populations of inoperable and high-risk patients. In the inoperable patients, the trials found that TAVR reduced mortality by 24.7 percent at two years, while reducing hospital readmission rates by 37.5 percent in the same period compared with patients managed by medications only. In patients who are deemed to be at high risk for conventional AVR, the trial showed that TAVR offered the same benefits and results without the risks of open-heart surgery. The Partner Trials paved the way for the FDA to clear TAVR for these two patient subgroups in 2011 and 2012.
More recently, in June 2014, the FDA allowed the use of a newer generation of valves called the Edwards Sapien valves. These valves promise to make the transcatheter surgery feasible for even more patients. The valves are bigger yet can pass through smaller femoral arteries. With the Edwards Sapien valves, post-operative
stroke rates have been reduce to around 3.2 percent.
Locally, a team of four doctors trained for 15 months to perfect the procedure. As of October 2014, seven patients have undergone TAVR utilizing the new generation of Sapien valves at Los Robles Hospital. Los Robles is the only hospital between Los Angeles and San Francisco that offers this new valve replacement option.
Among the seven patients that have undergone the procedure, two were deemed inoperable and the rest were considered high risk for conventional open-heart surgery. This group included two patients who were in their 90s and one who had end stage renal disease. Mortality, stroke and vascular complications have been zero thus far. Four of the patients left the hospital in four or fewer days. All seven have gotten a new lease on life.
A patient must be chosen with care for TAVR. TAVR requires cardiologists and cardiac surgeons to commit to a team approach to the process including the selection of the patients, procedural techniques and post-operative care. For high-risk patients, TAVR is the biggest breakthrough technology in heart care in over 50 years. It will save countless lives.
Dr. Gholam Mohammadzadeh is a Cardiovascular and Thoracic Surgery doctor in Thousand Oaks and is affiliated with Los Robles Hospital and Medical Center and Providence Tarzana Medical Center. 805-379-6717.