Caval-Aortic Access to Allow Transcatheter Aortic Valve Replacement in Otherwise Ineligible Patients Initial Human Experience

ObjectivesThis study describes the first use of caval-aortic access and closure to enable transcatheter aortic valve replacement (TAVR) in patients who lacked other access options. Caval-aortic access refers to percutaneous entry into the abdominal aorta from the femoral vein through the adjoining inferior vena cava.BackgroundTAVR is attractive in high-risk or inoperable patients with severe aortic stenosis. Available transcatheter valves require large introducer sheaths, which are a risk for major vascular complications or preclude TAVR altogether. Caval-aortic access has been successful in animals.MethodsWe performed a single-center retrospective review of procedural and 30-day outcomes of prohibitive-risk patients who underwent TAVR via caval-aortic access.ResultsBetween July 2013 and January 2014, 19 patients underwent TAVR via caval-aortic access; 79% were women. Caval-aortic access and tract closure were successful in all 19 patients; TAVR was successful in 17 patients. Six patients experienced modified VARC-2 major vascular complications, 2 (11%) of whom required intervention. Most (79%) required blood transfusion. There were no deaths attributable to caval-aortic access. Throughout the 111 (range 39 to 229) days of follow up, there were no post-discharge complications related to tract creation or closure. All patients had persistent aorto-caval flow immediately post-procedure. Of the 16 patients who underwent repeat imaging after the first week, 15 (94%) had complete closure of the residual aorto-caval tract.ConclusionsPercutaneous transcaval venous access to the aorta allows TAVR in otherwise ineligible patients, and may offer a new access strategy for other applications requiring large transcatheter implants

Incomplete retention after direct myocardial injection

Direct intramyocardial injection may permit local delivery of protein and gene therapy agents for myocardial and coronary artery disease. Little is known about the immediate fate of materials administered via percutaneous endomyocardial catheters or via surgical epicardial injection. In this study, we use a novel method to evaluate the acute retention of agents injected directly into the myocardium, compare epicardial with the percutaneous endocardial and postmortem delivery, and evaluate the influence of injectate volume on myocardial retention. Fifteen 40–50 kg pigs underwent overlapping myocardial injections using a percutaneous endomyocardial catheter, an epicardial needle via an open chest, and epicardial needle postmortem. Multiple distinct 15 Μ neutron-activated microsphere species were used as tracers. Two or three myocardial walls were injected in each animal using 3.5 mm, 27–28 gauge needles at varying injectate volumes. Animals were sacrificed immediately. Myocardial walls were divided and multiple microsphere species were quantified. In an additional study, nine 70 kg pigs underwent percutaneous endomyocardial injections with replication-deficient adenovirus encoding for the production of lac-Z. The injectate volume was varied, while the viral particle number remained constant. The animals were sacrificed 5 days after the percutaneous injections; the heart, liver, and spleen were collected for Β-galactosidase activity. Endomyocardial injection was associated with 43% ± 15% microsphere retention, compared with 15% ± 21% ( P < 0.01) retention of open chest epicardial injection and 89% ± 60% ( P < 0.01) for postmortem injection. Reducing the injectate volume from 100 to 10 ΜL improved microsphere retention ( P = 0.01). There was a trend toward improved viral transfection associated with smaller injection volumes. Despite direct intramyocardial administration, a significant fraction of injectate is not retained locally. Catheter-based needle endomyocardial injection is associated with equivalent or superior injectate retention compared with open chest epicardial injection. Proportionately, more injectate may be retained at lower volumes. Loss may involve a combination of channel leakage, venous, and lymphatic return. Cathet Cardiovasc Intervent 2002;55:392–397. © 2002 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/35254/1/10136_ftp.pd