James C. Fudge

Cutting balloon catheterization for interventional treatment of cor triatriatum dexter: 2 cases.

Cutting balloon dilatation was performed successfully in two dogs with cor triatriatum dexter and clinical signs of ascites. The cutting balloon catheter uses incisional microtomes embedded in a balloon catheter. During balloon expansion, these microtomes incise the adjacent tissue, decreasing circumferential wall stress. This theoretically reduces both the likelihood of fracturing the adjacent tissues in an uncontrolled manner and the potential neoproliferative response to standard balloon dilatation and the subsequent incidence of re-stenosis. In both cases described, clinical signs resolved completely following cutting balloon dilatation of the anomalous membrane. Based on the outcome of these 2 cases, cutting balloon dilatation appears to be a viable treatment option for dogs affected with cor triatriatum dexter.

Improving detection of hypertension in girls with turner syndrome using ambulatory blood pressure monitoring

Background/Aims: Turner syndrome (TS) is associated with increased mortality due to cardiovascular disease and a dramatically higher rate of aortic dissection. The recognition and treatment of hypertension in this population is critical. We sought to assess the ability to detect blood pressure (BP) abnormalities comparing ambulatory blood pressure monitoring (ABPM) with conventional BP measurement methods. We hypothesized that ABPM would improve detection of hypertension and alter management strategies. Methods: Twenty-three girls with TS underwent BP measurements using an automated oscillometric method and a manual mercury sphygmomanometer. Twenty-four-hour ABPM was performed (Spacelabs 90217, Issaquah, Wash., USA). BP values were compared to normative data based on height and sex for ABPM, and for age, height and sex for automated oscillometric and manual measurements. Results: Five (22%) subjects were found to have ambulatory hypertension (3 of these with severe hypertension). Three subjects had prehypertension using ABPM measurements. Only 1 of the 5 patients with ambulatory hypertension was categorized as hypertensive using manual BP measurements. Twelve subjects (52%) had nocturnal hypertension. ABPM data led to a change in medical management of hypertensive patients with initiation of antihypertensive therapy. Conclusions: ABPM is advantageous in TS, as it improves detection of hypertension, identifies those with non-dipping BP patterns, and changes medical management of patients.

Evaluation of the UF/NCI hybrid computational phantoms for use in organ dosimetry of pediatric patients undergoing fluoroscopically guided cardiac procedures

Epidemiologic data demonstrate that pediatric patients face a higher relative risk of radiation induced cancers than their adult counterparts at equivalent exposures. Infants and children with congenital heart defects are a critical patient population exposed to ionizing radiation during life-saving procedures. These patients will likely incur numerous procedures throughout their lifespan, each time increasing their cumulative radiation absorbed dose. As continued improvements in long-term prognosis of congenital heart defect patients is achieved, a better understanding of organ radiation dose following treatment becomes increasingly vital. Dosimetry of these patients can be accomplished using Monte Carlo radiation transport simulations, coupled with modern anatomical patient models. The aim of this study was to evaluate the performance of the University of Florida/National Cancer Institute (UF/NCI) pediatric hybrid computational phantom library for organ dose assessment of patients that have undergone fluoroscopically guided cardiac catheterizations. In this study, two types of simulations were modeled. A dose assessment was performed on 29 patient-specific voxel phantoms (taken as representing the patients true anatomy), height/weight-matched hybrid library phantoms, and age-matched reference phantoms. Two exposure studies were conducted for each phantom type. First, a parametric study was constructed by the attending pediatric interventional cardiologist at the University of Florida to model the range of parameters seen clinically. Second, four clinical cardiac procedures were simulated based upon internal logfiles captured by a Toshiba Infinix-i Cardiac Bi-Plane fluoroscopic unit. Performance of the phantom library was quantified by computing both the percent difference in individual organ doses, as well as the organ dose root mean square values for overall phantom assessment between the matched phantoms (UF/NCI library or reference) and the patient-specific phantoms. The UF/NCI hybrid phantoms performed at percent differences of between 15% and 30% for the parametric set of irradiation events. Among internal logfile reconstructed procedures, the UF/NCI hybrid phantoms performed with RMS organ dose values between 7% and 29%. Percent improvement in organ dosimetry via the use of hybrid library phantoms over the reference phantoms ranged from 6.6% to 93%. The use of a hybrid phantom library, Monte Carlo radiation transport methods, and clinical information on irradiation events provide a means for tracking organ dose in these radiosensitive patients undergoing fluoroscopically guided cardiac procedures.

Organ doses in pediatric patients undergoing cardiac‐centered fluoroscopically guided interventions: Comparison of three methods for computational phantom alignment

PURPOSE To assess various computational phantom alignment techniques within Monte Carlo radiation transport models of pediatric fluoroscopically guided cardiac interventional studies. METHODS Logfiles, including all procedure radiation and machine data, were extracted from a Toshiba infinix-I unit in the University of Florida Pediatric Catheterization Laboratory for a cohort of 10 patients. Two different alignment methods were then tested against a ground truth standard based upon identification of a unique anatomic reference point within images co-registered to specific irradiation events within each procedure. The first alignment method required measurement of the distance from the edge of the exam table to the top of the patients head (table alignment method). The second alignment method fixed the anatomic reference point to be the geometric center of the heart muscle, as all 10 studies were cardiac in nature. Monte Carlo radiation transport simulations were performed for each patient and intervention using morphometry-matched hybrid computational phantoms for the reference and two tested alignment methods. For each combination, absorbed doses were computed for 28 organs and root mean square organ doses were assessed and compared across the alignment methods. RESULTS The percent error in root mean square organ dose ranged from -57% to +41% for the table alignment method, and from -27% to +22% for the heart geometric centroid alignment method. Absorbed doses to specific organs, such as the heart and lungs, demonstrated higher accuracy in the heart geometric centroid alignment method, with average percent errors of 10% and 1.4%, respectively, compared to average percent errors of -32% and 24%, respectively, using the table alignment method. CONCLUSIONS Of the two phantom alignment methods investigated in this study, the use of an anatomical reference point - in this case the geometric centroid of the heart - provided a reliable method for radiation transport simulations of organ dose in pediatric interventional cardiac studies. This alignment method provides the added benefit of requiring no physician input, making retrospective calculations possible. Moving forward, additional anatomical reference methods can be tested to assess the reliability of anatomical reference points beyond cardiac centered procedures.

Pulmonary and tricuspid valvuloplasty in carcinoid heart disease

A 26‐year‐old female with carcinoid heart disease consisting of severe pulmonary and tricuspid valve stenosis was admitted with line associated sepsis. She recovered from sepsis with antibiotics and aggressive fluid resuscitation but became grossly volume overloaded with evidence of tense ascites and lower extremity edema. She developed worsening renal and hepatic function due to congestive nephropathy and hepatopathy, which did not respond to intravenous diuretics, and she was deemed too sick for surgical pulmonary and tricuspid valve replacement. Pulmonary and tricuspid valvuloplasty was performed as a rescue measure to alleviate her congestive symptoms and improve her candidacy for valve replacement.

Hybrid Stage 1 Palliation in a Patient With Hypoplastic Left Heart Syndrome and Unusual Decompressing Levoatrial Cardinal Vein in Turner Syndrome: Utility of Multimodality Imaging.

A newborn with prenatal diagnosis of Turner syndrome with hypoplastic left heart syndrome (HLHS) was born at term at our institution without perinatal complications. Prostaglandin (PGE) infusion was started, and the initial transthoracic echocardiogram (TTE) confirmed HLHS with severe mitral and aortic valve stenosis. There was a restrictive atrial communication with a large tortuous, decompressing levoatrial cardinal vein (LACV) that drained in a very unusual fashion to the superior vena cava (Figure 1A and B and Video 1). Family wished to pursue every available option, despite known poor outcomes with traditional stage 1 Norwood palliation in the 1 Pediatric Cardiology, University of Florida, Gainesville, FL, USA 2 UF Health Congenital Heart Center, University of Florida College of Medicine, Gainesville, FL, USA 3 Department of Pediatrics, Congenital Heart Center, University of Florida, Gainesville, FL, USA