香蕉直播

The wind howled across the jagged ridgeline, whipping at our jackets as we scrambled down another cliff face on Tasmania鈥檚 Western Arthurs, one of the wildest, most dangerous hikes in Australia. Clouds hung low, rain pelted sideways, and the narrow, muddy track snaked along edges where a single slip could mean disaster. But to my dad, this was heaven.

A seasoned mountaineer, my dad had spent his life adventuring, summiting peaks from the Andes to the Himalayas. To me, he was unbreakable, a force of nature with a grin, always chasing the next summit, the next storm. When park rangers stopped us and recommended we turn back due to the worsening weather, he just smiled and waved them off.

鈥淲e鈥檝e got the gear,鈥� he said, ducking into his pack and triumphantly pulling out two pairs of bright yellow dishwashing gloves. 鈥淲e鈥檒l ride it out.鈥� We pulled the rubber gloves over our woollen gloves - a bushwalker鈥檚 hack to keep our hands dry. The rangers seemed awfully confused, but after some more serious chats, allowed us to continue.

"That hike marked the moment I first understood the weight of a failing heart valve. Of course I had heard it before, the heart is the most important muscle in the body. But I didn鈥檛 truly understand what that meant until I saw my dad, the strongest person I knew, brought to exhaustion doing something he has done his entire life."

Mr Angus Grant

We pushed on through eight brutal days of rain, wind, and sheer ascents with fatal drops. To my surprise, the dishwashing gloves were a lifesaver, keeping our hands warm and core temperature up. But something else was wrong. On the climbs, I watched my dad鈥檚 boots drag a little more with every hill. Each step slower. Each breath heavier. At first, we thought it was just the flu causing his exhaustion, so we powered on. Still, it was jarring to see him struggle through terrain he once glided over.

He had undergone heart valve replacement surgery when I was twelve, but I barely registered it - a quiet medical event that happened in the background of childhood.

We finished the traverse, slowly and painfully. But when we returned home, his body didn鈥檛 bounce back. Fatigue lingered. Tests followed. The diagnosis hit hard: his artificial heart valve was failing, less than seven years after surgery. He would need another open-heart surgery to replace it, his second of what would eventually become several.

That hike marked the moment I first understood the weight of a failing heart valve. Of course I had heard it before, the heart is the most important muscle in the body. But I didn鈥檛 truly understand what that meant until I saw my dad, the strongest person I knew, brought to exhaustion doing something he has done his entire life.

The problem

The human heart has four valves which open and close with every beat, keeping blood flowing in the right direction. These valves ensure that blood moves efficiently through the heart and out to the rest of the body. When one fails, often due to age, disease, or damage, it can lead to fatigue, chest pain and heart failure.

For patients like my dad, the main treatment is valve replacement surgery which involves implanting an artificial valve made from animal tissue into the position of the diseased native valve. These are called bioprosthetic valves. They鈥檙e designed to mimic the natural motion of the heart and are preferred for their compatibility and low risk of blood clotting.

But there鈥檚 a catch: they don鈥檛 last

Over time, these valves begin to degrade. The tissue stiffens and the valve鈥檚 ability to open and close properly diminishes. Most bioprosthetic valves begin to fail within eight to10 years. For younger patients, that means repeat open-heart surgeries.

My dad鈥檚 valve didn鈥檛 even last seven years.

He鈥檚 not alone. Every year, over 300,000 people worldwide receive bioprosthetic valves, and many will need another.

鈥淪ome will go through this cycle two, three, even four times in their lifetime鈥�, says Professor Martin Ng, an interventional cardiologist at the Royal Prince Alfred hospital in Sydney鈥檚 inner west.

鈥淩epeat surgeries aren鈥檛 just physically taxing. They鈥檙e emotionally exhausting, financially draining, and each one increases the risk of complications.鈥�

What鈥檚 most frustrating is how slowly the valve industry moves. Bold, revolutionary valves sound exciting but, in reality, they face enormous barriers. Clinical trials take years. Regulatory approvals take longer. And even then, surgeons hesitate to adopt, not because they鈥檙e unwilling, but because they鈥檝e spent decades mastering older models.

鈥淣ew valves can feel unfamiliar, behave differently in the body, and add complexity to procedures surgeons have already perfected鈥�, says Joy Lee, a clinical consultant at a large valve manufacturing company.

鈥淭hey鈥檙e reluctant to be early adopters and prefer to wait for more clinical evidence, but this can take decades.鈥�

On average it takes 15 years for a new valve to go from initial design to widespread use in hospitals. The result? We鈥檙e still implanting valves made from the same material used in the early 2000s, the material that we all know leads to failure.

Think about how much the world has changed since the 2000s. In 2007, I still remember sitting in long queues of traffic approaching the Sydney Harbour Bridge, waiting in line to pay the toll fee at the toll booths, in cash! And if the toll booths weren鈥檛 enough, there were the maps.

On Saturday mornings, Dad would drive me to soccer and toss me the battered street directory, expecting a ten-year-old to navigate Sydney鈥檚 backstreets like a co-pilot in a rally car. 鈥淭hird left on O鈥機onnell Street in 300 metres!鈥� I鈥檇 yell, having absolutely no idea how far that was. We鈥檝e gone from glovebox maps to live traffic updates, from toll booths to contactless tags, from asking your kid for directions to arguing with Siri. So how are we up to the 24th generation of iPhones, but only the third generation of bioprosthetic heart valves?

This is what drew me into this field. I didn鈥檛 just want to understand why my dad鈥檚 valve failed, but I wanted to find a practical solution that could help patients now, not decades from now.

The biology

Bioprosthetic valve failure begins immediately after surgery, where the body鈥檚 immune system recognises the valve as foreign and slowly begins to attack. White blood cells gather, releasing proteins that slowly break down the valve material. Other immune cells send out chemical signals that create a cycle of low-grade inflammation. It's not an all-out attack, more of a chronic irritation that quietly eats away at the valve over time.

This inflammatory environment also causes calcium to build up on the valve surface. Bit by bit, these calcium deposits stiffen the valve, making it harder for them to open and close with each beat. Watching Dad struggle up those climbs, I was seeing this in real time. What starts as a small biological response eventually leads to mechanical breakdown. The only path from here is open-heart surgery to remove the degraded valve and implant a new one.

We often think of this failure as inevitable, like rust on a car. But what if it wasn鈥檛? What if we could protect the valve, camouflaging it from the body鈥檚 immune system as soon as it was implanted?

The solution

That鈥檚 where the work my colleagues and me in the Applied Materials Group at the Charles Perkins Centre, University of Sydney, comes in. Together, we鈥檝e been developing a coating that can be applied to existing bioprosthetic valves, simply by dipping the valve into a solution - like dipping metal into anti-rust paint. Within minutes, a microscopic film covers the valve and creates a natural interface between the valve and the body. Instead of triggering immune cells to attack, it encourages the growth of healthy, native cells to grow onto the valve surface.

The body therefore treats the valve as its own, preventing the long-term inflammation that leads to valve degradation and extending the lifespan of the implant. Crucially, this coating doesn鈥檛 alter the valve鈥檚 function or require surgeons to learn new techniques. It鈥檚 a minimal intervention, designed to improve on what already exists without being held up by the hurdles that often delay more revolutionary inventions.

Of course, we still need researchers chasing the big breakthroughs, the paradigm-shifting discoveries that redefine a field. But if every lab aims for revolution, we risk overlooking simple interventions that could transform lives today. That鈥檚 where we鈥檙e losing time, and where patients are paying the price.

At the Charles Perkins Centre, our strength lies in collaboration, in bringing together fundamental scientists, translational engineers, surgeons and policy experts to develop solutions that are not just scientifically sound, but ready for the real world. It鈥檚 this ecosystem that has allowed us to work on something as nuanced as a bioprosthetic heart valve coating, while still thinking broadly about systemic change. Because better health isn鈥檛 just about what鈥檚 possible, it鈥檚 about what鈥檚 practical.

The next leap forward won鈥檛 always be a giant one. Sometimes, it鈥檚 a pair of dishwashing gloves that keeps your hands dry in a storm. Sometimes, it鈥檚 a simple coating that helps a replacement heart valve last longer. Not revolutionary, but effective and ready to be used. My dad isn鈥檛 the only one who could benefit from this. There are millions of others living with chronic diseases who are waiting for 鈥榯he next big thing鈥�. But they need better, sooner. So let鈥檚 keep chasing the big ideas, but also champion the ones that are ready now, and build systems brave enough to support both.