Chinese researchers have made significant strides in treating hypertrophic cardiomyopathy (HCM), a condition that has posed a global health challenge since the late 1950s. Their breakthroughs have garnered worldwide attention and recognition.

For nearly four decades, there has been a dearth of specific drug treatments available, while the existing HCM medications can only manage symptoms rather than addressing the root cause of myocardial hypertrophy, according to professor Xie Xiaojie from the Department of Cardiology, the Second Affiliated Hospital, School of Medicine, Zhejiang University.  

Young patients, particularly adolescents, often experience more severe symptoms of HCM and are at a heightened risk of sudden cardiac death. This condition is a leading cause of fatal cardiac events in individuals under 35. As the disease progresses, complications such as heart failure, arrhythmia and stroke can arise, significantly impacting the physical and emotional well-being of patients and their families, Xie added. 

Xie said invasive procedures like surgery or interventional therapy can be effective but are complex, carry risks and are suitable for only a limited patient population. The development of new drug therapies has been a critical unmet need in the field consequently, Xie added.

A turning point arrived this year with China's approval of Mavaket capsules by the State Food and Drug Administration. This marks a global first as the world's initial selective cardiac myosin allosteric inhibitor. The drug offers fresh hope for adult patients in China grappling with obstructive hypertrophic cardiomyopathy.

Xie pointed out that Mavaket's mechanism of action bears similarities to targeted cancer therapies. It selectively decreases the ATPase activity of cardiac myosin heavy chain, effectively reducing excessive myosin-actin cross-bridge formation.

This process promotes a shift in the myosin group to an energy-conserving super-relaxed state, ultimately inhibiting excessive myocardial contraction and enhancing diastolic compliance and energy metabolism. The approval of this innovative drug is considered a monumental step forward in the treatment of hypertrophic cardiomyopathy.

Xie further explained that HCM can be categorized into two primary types: obstructive (HOCM) and non-obstructive. Common symptoms include shortness of breath, chest pain and fainting. These symptoms can often mimic other heart conditions, leading to overlooked or misdiagnosed cases.

Recognizing its significance, Mavaketel has been incorporated into several leading clinical guidelines. These include the "Chinese Hypertrophic Cardiomyopathy Guidelines 2022," "2023 Guideline for Diagnosis and treatment for Chinese Adult Patients with Hypertrophic Cardiomyopathy," "2023 ESC Guidelines for the Management of Cardiomyopathies" and "2024 AHA/ACC Guideline for the Management of Hypertrophic Cardiomyopathy."

This widespread endorsement solidifies Mavaketel's position as a preferred treatment option for patients with HOCM.

In addition, Chinese researchers have pioneered a beating-heart myectomy system and developed a minimally invasive procedure to treat HOCM.

The study was conducted by a research team led by Wei Xiang, a professor at the Tongji Hospital in Wuhan, central China's Hubei Province, and was published in the Journal of the American College of Cardiology.

It is estimated that there are about 2 to 5 million patients with HOCM in China, and the global population of such patients stands at approximately 15 to 20 million, posing a serious threat to human health.

Currently, the conventional treatment for HOCM is through open-chest surgery to resect the hypertrophic myocardium. This surgical method is not only highly invasive but also technically challenging, resulting in suboptimal outcomes and high mortality rates in hospitals with less experience.

The novel transapical beating-heart septal myectomy procedure has overcome the limitations of traditional open-chest procedures, allowing for the precise resection of hypertrophic myocardium without the need for chest opening, cessation of the heartbeat, or blood transfusion.

Wei was recently invited to the Mayo Clinic, a world-renowned cardiovascular treatment center in the United States, to discuss this groundbreaking medical breakthrough. Cardiac surgeons from countries and regions such as the United States, Switzerland and Italy have also traveled to China to learn about the technology. 

"In the field of HOCM surgery, we used to follow the world, but now we are keeping pace with it or even leading," Wei said.

(With input from Xinhua)