Cath Lab Digest

BACKGROUND
Left ventricular direct access and sheath placement through a mini-thoracotomy has been utilized to allow minimally invasive valvular surgery. One potential problem encountered is the closure of the ventricular puncture incision in a beating heart. Our aim was to develop a sutureless closure technique which does not leave behind a foreign body exposed on the endocardial surface.

METHOD
We sought to evaluate this concept in-vivo in the porcine model. Thoractomy was performed with exposure of the beating heart. Six-French sheaths were placed in the transapical territory in the left ventricle and right ventricle, with fluoroscopy confirming sheath placement. The incisions were then closed using three types of commercially available femoral vascular closure systems (AngioLink™, StarClose™ and Mynx™).

RESULTS
One animal had 1 device placed in each of the left and right ventricles and closure was immediately observed intra-operatively (AngioLink™). Another animal had 5 devices (StarClose™) placed in the left ventricle and 1 in the right ventricle, with closure observed within 1 minute of application. A third animal had removal of the sheath and spontaneous closure observed at two sites. These two sites continued to bleed for 2 to 3 minutes. The same animal underwent application of 6 Mynx™ devices at sheath sites using an extravascular bio-inert sealant. One site failed and five others were immediately successful. Histopathological evaluation confirmed no evidence of device exposure on the endovascular surface in the first 2 animals. The Mynx™ device sealant was present on the endocardial surface at closure sites post mortem.

CONCLUSION
We have introduced a new concept of using vascular closure systems for closing ventricular wall-stab incisions after transapical surgery. We intend to expand the scale of animal studies and evaluate the device for any modifications in mechanism or technique for ultimate use in human subjects.

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Richard R. Heuser, MD, FACC, FACP, FESC, FSCAI, is an internationally recognized cardiologist, inventor, educator and author. A diplomate of the American Board of Cardiovascular Diseases and the American Board of Interventional Cardiovascular Diseases, Dr. Heuser is one of the early pioneers of angioplasty and is considered one of American’s top cardiologists. Dr. Heuser is currently in practice at the Phoenix Heart Center/Physicians Group of Arizona. He is Director of Cardiology and Chief of Cardiac Catheterization Laboratory at St. Luke’s Hospital and Medical Center, Phoenix, Arizona, and Clinical Professor of Medicine at the University of Arizona College of Medicine, as well as Director of the Interventional Fellowship Program at the University of Arizona College of Medicine, Phoenix Campus.

With 13 patents granted for different catheters stents and other medical devices, Dr. Heuser has served as a principal investigator to research the safety and/or effectiveness of more than 100 medical devices and 50 pharmaceutical products, and has participated in more than 20 research studies. He has authored numerous articles, textbooks and medical manuscripts, and is frequency invited to international medical conferences to present findings of research developed in Phoenix.

Dr. Heuser received his medical degree from the University of Wisconsin School of Medicine in Madison, Wisconsin, and completed his medicine internship and residency, as well as his cardiology fellowship, at the Johns Hopkins Hospital in Baltimore, Maryland.