A novel catheter technique for patching holes in the heart may make it possible for many patients to avoid surgery altogether and others to regain enough strength to safely undergo surgical repair at a later date, according to a study reported at the 30th Annual Scientific Sessions of the Society for Cardiovascular Angiography and Interventions, May 9–12, 2007, in Orlando, FL.
The patch successfully closed ventricular septal defects (VSDs)—or ruptures in the wall between the right and left ventricles—in nearly all patients, allowing blood to circulate normally again and relieving fluid back-up in the lungs. After recovery, patients were able to return to active lives.
"Patients with acute VSDs may be critically ill with heart failure and perhaps be in cardiogenic shock," said Matthew W. Martinez, M.D., a cardiology fellow at the Mayo Clinic in Rochester, MN. "This procedure offers an alternative for patients who are too sick to undergo emergency heart surgery or simply don't want surgery."
To track the long-term effectiveness of the catheter procedure, Dr. Martinez and his colleagues reviewed the medical records of 10 patients treated with the VSD patch between 1995 and 2005. Of these, 5 patients experienced rupture of the ventricular wall, or septum, as a result of a heart attack. In the other 5 patients, the VSD was an unintended consequence of a previous heart surgery.
In all cases, the VSD allowed a portion of the blood in the left ventricle to shoot backward into the right ventricle with each heart beat, rather than being circulated to the rest of the body. As a result, patients were experiencing such severe heart failure they were short of breath at rest or with minimal activity, and were judged to have New York Heart Association class 3 and 4 heart failure.
A variety of patches were used in the study, but all were some form of AMPLATZER Occluder (AGA Medical Corp., Plymouth, MN). The VSD patch is composed of two discs connected by a thick shaft. The discs are made of flexible nitinol metal and covered in polyester fabric that encourages heart tissue to grow over the discs, completely covering them during healing.
Before implantation, the flexible double-disc patch is pulled into a catheter, collapsing and compressing it lengthwise. It is then threaded through a vein into the right ventricle and across the rupture into the left ventricle. The patch is pushed partially out of its catheter sheath until the first disc pops open. The catheter is then withdrawn back into the right ventricle, with the first disc positioned against the left ventricular wall and the connecting shaft filling the hole created by the rupture. From inside the right ventricle, the patch is pushed forward again, releasing the second disc, which covers the rupture on the right side of the heart.
Implantation of the VSD occluder was performed by Donald J. Hagler, M.D., FSCAI, a professor of pediatrics in the Divisions of Pediatric Cardiology and Cardiovascular Diseases at the Mayo Clinic. The procedure was successful in all patients, without complications. One patient died 5 days later of illness unrelated to the VSD patch. In 2 patients, the rupture didn't fully heal, causing damage to blood cells as they jetted through the narrow opening. A third patient developed a bacterial infection that started several months after device implantation. The patch was removed and all 3 patients had successful surgery to repair the rupture.
Even in such cases, the VSD patch serves its purpose by allowing patients to regain enough strength to withstand surgery, Dr. Martinez said. "Surgery is the long-term answer for some patients," he said. "In such cases, the VSD occluder successfully bridges the patients to surgery."
After a follow-up that averaged more than 1 year, patients were feeling markedly better and were much more active, even able to climb a flight of stairs before becoming short of breath. All patients were ranked in New York Heart Association class 2 or better.
Kathy Boyd David | EurekAlert!
Skin patch dissolves 'love handles' in mice
18.09.2017 | Columbia University Medical Center
Medicine of the future: New microchip technology could be used to track 'smart pills'
13.09.2017 | California Institute of Technology
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
21.09.2017 | Physics and Astronomy
21.09.2017 | Life Sciences
21.09.2017 | Health and Medicine