John Crouch

Open versus endoscopic saphenous vein harvesting: wound complications and vein quality

BACKGROUND The saphenous vein is an important conduit for coronary artery bypass grafting. Wound complications from traditional open vein harvesting occur often. Minimally invasive endoscopic saphenous vein harvesting may decrease wound complications. Vein quality may be an issue with endoscopic harvesting. METHODS We reviewed 568 patients who had bypass grafting and saphenous vein harvesting either endoscopic (group A, n = 180) versus open (group B, n = 388). Both groups were demographically similar and management identical. Wound complication was defined by the need for intervention and included lymphocele, hematoma, cellulitis, edema, eschar, and infection. Multiple vein segments were obtained from 8 patients, 4 from each group, and examined histologically. RESULTS Wound complications were significantly less in group A (9/180, 5%) versus group B (55/388, 14.2%), p value equal to or less than 0.001. Open harvesting (p< or =0.001), diabetes (p< or =0.001), and obesity (p< or =0.02) were risk factors for wound complication by univariate analysis. By multiple logistic analysis, open harvesting (p< or = 0.0007) and diabetes (p< or =0.0001) were independent risk factors for wound infection. Histologic evaluation of vein samples showed that there was no difference between the groups and vascular structural integrity was maintained. CONCLUSIONS Endoscopic saphenous vein harvesting was associated with fewer wound complications and infections. Vein quality was not adversely effected because of endoscopic harvesting.

The Acute Effects of Pneumonectomy on Pulmonary Vascular Impedance in the Dog

Pulmonary vascular impedance is a measure of the pulsatile characteristic of pressure and flow that occurs in the proximal pulmonary arteries. Pulmonary vascular resistance (PVR) is most influenced by the distal circulation of the lung. This study was performed to evaluate the changes that occurred in pulmonary vascular impedance, as well as in other hemodynamic variables, following pneumonectomy by a closed-chest method in 10 anesthetized dogs. The following observations were made (numbers compare mean values for the 10 dogs before and after pneumonectomy): (1) PVR increased from 447 to 761 dyne sec cm-5 (p = .02); (2) the oscillatory work of the right ventricle increased from 1.23 to 1.76 J/min (p = .006); (3) the mean pulmonary artery pressure increased from 14 to 18.8 mm Hg (p = .0001); and (4) cardiac output and heart rate remained unchanged. Surprisingly, the estimated characteristic impedance (the impedance to oscillatory flow in the proximal bed) did not change significantly (279 to 296 dyne sec cm-5). This observation cannot be explained by the usual lumped compartmental models classically used to characterize the pulmonary vascular bed.

Emergency Medical Text Classifier: New system improves processing and classification of triage notes

Objective Automated syndrome classification aims to aid near real-time syndromic surveillance to serve as an early warning system for disease outbreaks, using Emergency Department (ED) data. We present a system that improves the automatic classification of an ED record with triage note into one or more syndrome categories using the vector space model coupled with a ‘learning’ module that employs a pseudo-relevance feedback mechanism. Materials and Methods: Terms from standard syndrome definitions are used to construct an initial reference dictionary for generating the syndrome and triage note vectors. Based on cosine similarity between the vectors, each record is classified into a syndrome category. We then take terms from the top-ranked records that belong to the syndrome of interest as feedback. These terms are added to the reference dictionary and the process is repeated to determine the final classification. The system was tested on two different datasets for each of three syndromes: Gastro-Intestinal (GI), Respiratory (Resp) and Fever-Rash (FR). Performance was measured in terms of sensitivity (Se) and specificity (Sp). Results: The use of relevance feedback produced high values of sensitivity and specificity for all three syndromes in both test sets: GI: 90% and 71%, Resp: 97% and 73%, FR: 100% and 87%, respectively, in test set 1, and GI: 88% and 69%, Resp: 87% and 61%, FR: 97% and 71%, respectively, in test set 2. Conclusions: The new system for pre-processing and syndromic classification of ED records with triage notes achieved improvements in Se and Sp. Our results also demonstrate that the system can be tuned to achieve different levels of performance based on user requirements.

The use of angiodynography to quantify blood flow in the canine aorta

Previous attempts to quantify blood flow by means of ultrasound have been hampered by inaccurate diameter measurements and failure to account for the parabolic nature of the cross-sectional velocity profile. Angiodynography (ADG) provides a B-mode image of vessel walls, and the outer flow envelope is constantly monitored to provide phasic diameter measurements throughout the cardiac cycle. Frequency shifts are color-coded to provide a real-time visual display of varying velocity patterns across the vessel lumen throughout the cardiac cycle as well as calculation of average flow velocity and mean blood flow. Simultaneous flow values obtained with ADG were compared with electromagnetic flow probe (EMF) measurements in 12 open-chest dogs. Flow was varied with volume administration and exsanguination, and 201 data points were obtained. The average flow determined by EMF was 2.0 +/- 0.9 L/min compared with 2.04 +/- 0.71 L/min for ADG. The correlation coefficient was 0.88, the y-intercept was close to zero, and the slope approached unity, confirming the ability of ADG to accurately determine volume blood flow rather than merely to establish a flow trend. It is concluded that ADG offers an accurate way of quantifying volume blood flow.

Biatrial High-Grade Leiomyosarcoma With Nine-Year Post-Surgical Survival

Primary cardiac leiomyosarcoma is a rare tumor with poor prognosis. We present a 53-year-old female patient with biatrial leiomyosarcoma with inferior vena cava and coronary sinus involvement who underwent aggressive surgical resection with reconstruction of her left and right atrium and coronary sinus with bovine pericardium followed by adjuvant radiation therapy. She is living well with no recurrence 9 years after diagnosis.

Association between sleep disordered breathing and life threatening ventricular arrhythmia among left ventricular assist device patients

The association between sleep disordered breathing (SDB) and ventricular arrhythmias (VA) is well established. Limited data is available on the severity of SDB and VA among patients with continuous flow left ventricular assist device (CF-LVAD). Among 230 patients who received CF-LVAD between Jan

Prophylactic use of thoracic endovascular aortic repair in a young patient with impending aortic rupture

Prophylactic thoracic endovascular aortic repair (TEVAR) was successfully performed on a 22-year-old female who was incidentally found to have left-sided T8 and T9 pedicle screws from a prior thoracic spine fusion surgery for scoliosis indenting the descending thoracic aorta (DTA) on a computed tomography (CT) scan of the chest (red arrow, Fig. 1a). Subsequent CT angiography (CTA) and 3-dimensional reconstruction (3DR) images of the DTA demonstrated the left T9 pedicle screw indenting the posterior medial DTA by 4 mm and the left T8 pedicle screw abutting the posterior medial margin of the DTA with no associated leak or pseudoaneurysm (red arrows, Fig. 1b and c). To avoid rupture of the DTA, prophylactic TEVAR was deemed appropriate. After fluoroscopic confirmation of the indentation (red arrow, Fig. 1d, Online Video 1), two Endurant aortic cuff grafts (Medtronic, Minneapolis, Minn.) (size 23 × 23 × 70 mm) were successfully deployed in an overlapping fashion to allow two layers of stent graft at the site of the aortic indentation without any immediate complications. Follow-up at 1 year with repeat CTA and 3DR imaging of the DTA revealed no complications and maintained aortic integrity (Fig. 1e, f, and g). TEVAR is the preferred therapeutic modality for the treatment of various DTA pathologies. To our knowledge, this is the first case of the unique use of TEVAR in a patient with impending aortic rupture due to pedicle screws.

Does Left Ventricular Assist Device Implantation Affect Driving Patterns in Patients With End-Stage Heart Failure?

Background In 2012, the Canadian Society of Cardiology indicated that patients supported with left ventricular assist device (LVAD) may drive a private vehicle 2 months after implantation, provided they are deemed clinically stable. Objective evidence supporting this recommendation is limited. We sought to compare data regarding driving habits in our patients following LVAD implantation. Citation: Pinniti M.et al. (2017) “Does Left Ventricular Assist Device Implantation Affect Driving Patterns in Patients With EndStage Heart Failure?” The VAD Journal, 3. doi: https://doi.org/10.13023/VAD.2017. 05 Editor-in-Chief: Maya Guglin, University of Kentucky Received: February 15, 2016 Accepted: March 16, 2017 Published: March 16, 2017

Favorable Outcomes of LVAD as Bridge to Simultaneous Heart-Kidney Transplantation

Chronic kidney disease (CKD) is an established risk factor for incident cardiovascular disease and progression of heart failure disease state, and is associated with decreased survival after left ventricular assist device (LVAD) therapy or heart transplantation (HT). Combined heart-kidney transplantation (HKT) compared with isolated HT recently has been shown to have survival advantage among patients whose estimated glomerular filtration rate is less than 37 ml/min/m2. Data on LVAD to HKT are limited.

Expecting the unexpected: right atrial mass in a transplant patient

We present a 71‐year‐old male, who had had a heart transplantation 24 years prior, who came to our clinic with a low‐grade fever and a new II/VI holosystolic murmur. Echocardiography showed a large mass in the right atrium with attachment near the junction of the right atrium and superior vena cava. The patient was taken to the operating room for resection of the mass. Microscopic evaluation was consistent with thrombus. Differential diagnosis of cardiac masses after cardiac transplant includes tumour, thrombus, and vegetation. Final diagnosis can be challenging; multimodality imaging and biopsy or resection often are required for final diagnosis.