MR Enhancing Implants

TY - CHAP

T1 - MR Enhancing Implants

AU - Melzer, Andreas

AU - Immel, Erwin

AU - Boyd, Richard

AU - Wendt, Daniel

N1 - Copyright: © Springer Science+Business Media New York 2014.

PY - 2014

Y1 - 2014

N2 - Implantation of cardiovascular implants such as stents, prosthetic heart valves or vena cava filters (VCF) are usually performed using X-ray-based imaging techniques (fluoroscopy) in a cath lab. Possible migration and intraluminal changes in the implants require a post interventional follow-up diagnostic procedure. For example, restenosis (up to 25 %) and late in-stent thrombosis (up to 2 % by in drug-eluting stents and despite dual anti-platelet therapy with aspirin and thienopyridine up to 6 % in diabetes patients) frequently occur after the implantation of a vascular stent. Vena cava filter is by nature subject of thrombus capturing. For explantation and retrieval, it must be assured that no large blood clot formations are still present in the filter. Prosthetic heart valves and the recently introduced balloon and self-expanding heart valves for transapical and TAVI procedure require follow-up imaging of possible complications such as paravalvular leakages, valve thrombosis or malfunction of the valve leaflets which are made of bovine pericardium or porcine heart valves. Therefore, post interventional non-invasive follow-up diagnostic is needed. Transthoracic ultrasound (TUS) is the method of choice for routine follow-up but due to the sound scattering at the valve scaffold, diagnosis is compromised. More thorough diagnosis can be achieved by invasive techniques such as transesophageal endoscopic ultrasound (TEE) or intravascular ultrasound (IVUS) reveals more information but still the sound scattering leaves gaps in the diagnoses of valve function. X-ray-based invasive imaging with iodinated contrast agents can be applied but the disadvantage of this diagnostic method is, additional to the ionising radiation, adverse reactions to iodinated contrast agents. This includes general (acute and delayed) and organ-specific adverse effects (contrast-induced nephrotoxicity and cardiovascular, pulmonary and neurotoxicity) and occurs, for example, in 17–35 % of patients with history of previous adverse reaction (some of the predisposing factors for an adverse reaction are: infants and elderly, history of asthma or allergy, dehydration and heart disease).

AB - Implantation of cardiovascular implants such as stents, prosthetic heart valves or vena cava filters (VCF) are usually performed using X-ray-based imaging techniques (fluoroscopy) in a cath lab. Possible migration and intraluminal changes in the implants require a post interventional follow-up diagnostic procedure. For example, restenosis (up to 25 %) and late in-stent thrombosis (up to 2 % by in drug-eluting stents and despite dual anti-platelet therapy with aspirin and thienopyridine up to 6 % in diabetes patients) frequently occur after the implantation of a vascular stent. Vena cava filter is by nature subject of thrombus capturing. For explantation and retrieval, it must be assured that no large blood clot formations are still present in the filter. Prosthetic heart valves and the recently introduced balloon and self-expanding heart valves for transapical and TAVI procedure require follow-up imaging of possible complications such as paravalvular leakages, valve thrombosis or malfunction of the valve leaflets which are made of bovine pericardium or porcine heart valves. Therefore, post interventional non-invasive follow-up diagnostic is needed. Transthoracic ultrasound (TUS) is the method of choice for routine follow-up but due to the sound scattering at the valve scaffold, diagnosis is compromised. More thorough diagnosis can be achieved by invasive techniques such as transesophageal endoscopic ultrasound (TEE) or intravascular ultrasound (IVUS) reveals more information but still the sound scattering leaves gaps in the diagnoses of valve function. X-ray-based invasive imaging with iodinated contrast agents can be applied but the disadvantage of this diagnostic method is, additional to the ionising radiation, adverse reactions to iodinated contrast agents. This includes general (acute and delayed) and organ-specific adverse effects (contrast-induced nephrotoxicity and cardiovascular, pulmonary and neurotoxicity) and occurs, for example, in 17–35 % of patients with history of previous adverse reaction (some of the predisposing factors for an adverse reaction are: infants and elderly, history of asthma or allergy, dehydration and heart disease).

KW - Heart Valve

KW - Larmor Frequency

KW - Prosthetic Heart Valve

KW - Radio Frequency Pulse

KW - Resonant Circuit

UR - https://www.scopus.com/pages/publications/105041889519

U2 - 10.1007/978-1-4614-7657-3_55

DO - 10.1007/978-1-4614-7657-3_55

M3 - Chapter (peer-reviewed)

AN - SCOPUS:105041889519

SN - 9781461476566

SP - 725

EP - 737

BT - Intraoperative Imaging and Image-Guided Therapy

A2 - Jolesz, Ference A.

PB - Springer New York

CY - New York

ER -