balloon catheters coated by Freudenberg


Improving the flow

Narrowing of the blood vessels often poses a serious threat to the health of elderly people. Innovative balloon catheters coated by Hemoteq, a Freudenberg Medical company, noticeably improve patients’ quality of life and make an effective contribution to sustainability.

When a blood vessel narrows, danger lurks deep inside the human body. Such so-called "stenoses" caused by arteriosclerosis can lead to cardiovascular disease – one of the most frequent causes of death worldwide. If a blood clot blocks a narrowed coronary artery, the resulting lack of oxygen often causes a life-threatening heart attack. If the carotid artery is affected by vasoconstriction, there is a risk of stroke. And finally, if the pelvic and leg arteries are narrowed by arteriosclerosis, peripheral arterial occlusive disease sometimes occurs. Patients then suffer from pain in their legs when walking, due to circulatory problems, and must take frequent breaks – even over short distances.

Dr. Hans Krankenberg

Deposits in the vessel walls

How does this dangerous narrowing of the blood vessels occur? "Vasoconstriction is caused by an increased concentration of plaque over decades in the vessel walls – blood fats, blood clots, connective tissue and calcium. Risk factors include smoking, lipid metabolic disorders with elevated LDL cholesterol levels, high blood pressure, obesity and diabetes mellitus. Lack of exercise over many years also plays a significant role. At an advanced stage, arteriosclerosis cannot be cured; however, it can be treated," says PD Dr. Hans Krankenberg, principal consultant for angiology at the Asklepios Clinic in Harburg, Germany. The internal medicine, angiology and cardiology specialist has been dealing with the secondary diseases of arteriosclerosis, such as peripheral arterial occlusive disease, for many years. He has found that conservative treatments have a limited effect: “A healthy lifestyle, nicotine withdrawal, weight reduction, anticoagulant drugs such as acetylsalicylic acid (ASA) and frequent walking can help but are not routinely put into practice by patients,” says Hans Krankenberg talking from experience.

Drug-coated stents and balloon catheters: the preferred therapy

Stent and balloon catheter treatment is much more effective. Stents are tubular, mostly metallic implants of a few millimeters’ diameter. Using keyhole surgery, they are placed at the narrowing of the vessels to restore blood flow. With balloon dilation, a delicate balloon is guided directly to the stenosis on a thin catheter and then inflated to mechanically widen the vessel. The balloon catheter is removed immediately after the procedure. Often, the two methods are combined. Nonetheless, it is still possible for the blood vessels to narrow again after a few months. “To reduce the risk of re-stenosis, the preferred therapy is to coat stents and balloon catheters with cell growth-inhibiting drugs,” says Dr. Krankenberg.

As precise as a stamping process

This is where Hemoteq AG, a Freudenberg Medical company, comes into play: After many years of research, the company has succeeded in improving drug-donating balloon dilation using an innovative coating technology. “The drug-coated balloon catheter’s active ingredient is released from the balloon’s surface into the vessel wall,” says Dr. Michael Hoffmann, CEO and co-founder of Hemoteq AG. True to all Freudenberg innovations, the Group’s expertise lies in both the material and the process. Hemoteq's research team first looked at which drug and with which formulaic properties is best suited for coating the balloon catheter and for absorption into the vessel wall. After numerous studies, the drug paclitaxel is usually used. With special additives, it can form tiny, needle-shaped crystals on the balloon’s surface that can transfer well to the vessel wall. “We have reached the point whereby the balloon presses the active ingredient against the vessel wall like a stamp, delivering the drug precisely to where it is needed,” says Dr. Hoffmann. Paclitaxel is in fact a cancer drug that, in small doses, can also prevent vessel-wall growths from vascular diseases- thereby keeping the blood vessel permanently open.

The balloon catheter: the balloon at the end of the tube is guided to the constriction in the body’s vascular system where it inflates and widens the blood vessel.

Innovative coating technology

How Hemoteq applies the drug to the catheter is crucial. The balloon catheter, manufactured by a different company, is folded on delivery. The balloons must be completely and consistently coated with the correct dosage of the drug. A so-called drag and drop process makes this possible. In a special device, a movable nozzle applies a drop of the pharmacological coating solution to the surface of the rotating balloon. The drop is “dragged” continuously along the balloon’s length and penetrates deep into the folds. Hemoteq’s highly-efficient, camera-monitored and automated coating process delivers the medication precisely to where the body needs it, prolonging and improving the drug’s effect.

Contribution to greater sustainability

Ingenuity at its best: “Thanks to Hemoteq technology, balloon coating will become much more efficient: Compared to other industrial solutions, the Paclitaxel dose applied to the balloon is significantly lower but equally effective. “This reduction improves sustainability in many ways – health is a key sustainability theme at Freudenberg,” says René Heilmann, Head of Marketing at Freudenberg Medical. First and foremost, the patient benefits, as the lower drug dose improves therapy: fewer side effects, less follow-up treatment.

René Heilmann

This and high product efficacy, generate better quality of life. The contribution to environmental protection is also considerable, as a reduction in the use of medication cuts down on cytotoxic waste in hospitals. Finally, production costs are lower, potentially saving the healthcare system money. Dr. Krankenberg is satisfied with the medical progress made using coated balloon catheters: "Studies and clinical practice show that vessels treated in this way stay open much longer – significantly improving patient health.” However, the physician also says: “The research goes on; we have not yet reached the end of the line.” One thing is clear: Freudenberg is doing everything possible to drive forward further groundbreaking and sustainable innovations – including those for treating vascular constriction.


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