Is Neurogenic Bladder a Risk Factor for Febrile Urinary Tract Infection After Ureteroscopy and, if so, Why?

OBJECTIVE: To characterize the rate of febrile urinary tract infections (UTIs) after ureteroscopy in patients with neurogenic bladder compared with those with physiologically normal bladders. Although generally considered safe and effective, there is a growing body of evidence suggesting that patients with neurogenic bladder are at an increased risk of infectious complications following ureteroscopy. METHODS: We performed a retrospective chart review of those undergoing ureteroscopy in a single academically affiliated hospital system between June 2013 and May 2016. Information regarding neurogenic bladder status, culture results, bladder management, and the presence of upper tract decompression was collected. Postoperative febrile UTI was defined as a hospital admission within 1 week of surgery because of fever not attributable to another source. RESULTS: Of 467 ureteroscopies, 44 (9.5%) were performed in the setting of neurogenic bladder. Febrile UTI rates were higher in patients with neurogenic bladder compared with control patients (9% vs 1.4%, P = .01) with significantly higher rates in those dependent on bladder catheterization. Interestingly, the presence of a nephrostomy tube in patients with physiologically normal bladders increased the risk of postoperative febrile UTI to levels comparable with patients with neurogenic bladder who were catheter dependent (10.5% vs 12.5%, respectively). CONCLUSION: Although infectious complications in the neurogenic population are likely multifactorial, the reliance on catheterization and thus colonization appears to be a significant factor and extends to non-neurogenic patients. These data suggest that bacterial colonization may be the significant underlying risk factor for febrile UTI after ureteroscopy.

An automated coring and apical connector insertion device facilitates aortic valve bypass (apicoaortic conduit) surgery: preclinical experience in a chronic ovine model.

BACKGROUND AND AIM OF THE STUDY: Aortic valve bypass (AVB, apicoaortic conduit) surgery is an alternative treatment for high-risk patients with aortic stenosis (AS). An automated coring and connector insertion device designed to simplify the apical AVB anastomosis has been developed. The applicator consists of a toroidal shaft-mounted balloon, an integrated circular coring knife, and a stented apical connector supporting a Dacron graft. In this way, apical myocardial coring, connector insertion and core removal may be automated. METHODS: AVB was performed without cardiopulmonary bypass in eight sheep. A conduit containing a porcine valve was anastomosed to the descending aorta using a partial occlusion clamp. The applicator was used to insert the apical connector, and the connector and conduit were joined with a quick-connector. The descending aorta was occluded proximal to the distal anastomosis to simulate AS. Gradients across the conduit were measured after implantation, and one month later at sacrifice. RESULTS: All AVB implants were performed successfully. The median blood loss was 50 ml (IQR: 13- 98 ml). The median connector implantation time was 29 s, and the peak gradients across the conduit early and at 30 days after AVB were 5.2 +/- 2.6 mmHg and 2.7 +/- 1.4 mmHg, respectively. One animal died of hemothorax at 24 h after surgery, but all remaining animals survived and gained weight. Gross and histopathologic assessments demonstrated widely patent conduits and normal brain histology in all animals. CONCLUSION: The applicator facilitated the safe and expeditious performance of AVB surgery. The clinical use of this device will improve the safety and increase the adoption of this beating-heart therapy for AS.

Magnetic resonance investigation of blood flow after aortic valve bypass (apicoaortic conduit).

BACKGROUND: Aortic valve bypass (AVB, apicoaortic conduit) is an alternative to aortic valve replacement (AVR) for high-risk patients with aortic stenosis (AS). The redistribution of blood flow after AVB has been poorly characterized. In order to understand cardiovascular physiology after AVB, we performed cardiac magnetic resonance (CMR) imaging of AVB recipients. METHODS: Fifteen patients with symptomatic AS underwent beating-heart AVB. Electrocardiography-gated two-dimensional phase-contrast velocity mapping CMR imaging was conducted on each patient. Instantaneous flow was acquired at discrete intervals within the cardiac cycle and ventricular function and volumes were evaluated. Five age-matched patients without aortic valve disease served as controls. RESULTS: Conduit flow (as a percent of total cardiac output) was 65% ± 5%. Ejection fraction was unchanged compared with before AVB (50% ± 17% versus 57% ± 13%; p = 0.91). Ventricular volumes and cardiac indices were within normal limits and similar to those values in controls (cardiac index 2.9 ± 1.0 versus 2.3 L/min/m(2); p = 0.26; end-diastolic volume index 59 ± 17 mL versus 55 ± 20 mL; p = 0.66; end-systolic volume index, 25 ± 12 versus 25 ± 18 mL; p = 0.91; stroke volume index, 33 ± 11 versus 30 ± 6 mL; p = 0.57 for AVB and control patients, respectively). There was a small degree of retrograde blood flow in the descending aorta above the level of the conduit insertion (10% ± 8% of cardiac output). CONCLUSIONS: Aortic valve bypass results in a predictable blood flow distribution between the native aorta and conduit and is associated with normal ventricular volumes and function.

Undersized tricuspid annuloplasty rings optimally treat functional tricuspid regurgitation.

BACKGROUND: In contrast to mitral valve repair, residual and recurrent regurgitation after tricuspid valve (TV) repair for functional tricuspid regurgitation (TR) is common. We have systematically used undersized, rigid 3-dimensional annuloplasty rings to treat functional TR. METHODS: From March 2006 to October 2009, 101 consecutive patients with moderate or greater functional TR underwent TV repair with an undersized rigid 3-dimensional annuloplasty ring. All patients had a predischarge echocardiography evaluation in a core echocardiography laboratory. Follow-up echocardiography was available for 96% of surviving patients. Mean follow-up was 17±9 months. RESULTS: Twenty-nine percent of patients had undergone previous cardiac operations, 74% were in New York Heart Association functional class III or IV, and 48% had atrial fibrillation. Mitral valve operations were performed in 93 patients, aortic valve operations in 17, coronary artery bypass grafting in 21, and CryoMaze procedures in 40. Size 26 or 28 rigid tricuspid annuloplasty rings were used in 88% of patients, and no ring larger than a 28 has been used since November 2008. The operative mortality rate was 6% (n=6). Freedom from significant TR (TR>moderate) at hospital discharge, as assessed by the clinical core laboratory, was 97%. Only 3% of patients had TR greater than moderate during follow-up. No patient required TV reoperation. New postoperative permanent pacemakers were inserted in 3 patients. CONCLUSIONS: Tricuspid valve repair with an undersized (size 26 or 28) rigid 3-dimensional annuloplasty ring is the method of choice for reliable and durable treatment of functional TR.

Mitral regurgitation: current trends in diagnosis and management.

Mitral regurgitation is the most prevalent heart valve disorder in the United States. Individuals with mitral regurgitation may be asymptomatic or may present with dyspnea, orthopnea, fatigue, and/or heart rhythm disturbances. Long-standing mitral regurgitation causes chronic left ventricular volume overload, which leads to left ventricular dilation and contractile dysfunction. Without treatment, mitral regurgitation results in biventricular failure and death. Echocardiography is the preferred diagnostic test to assess the presence and severity of mitral regurgitation. Mitral valve surgery, the only effective treatment for patients with severe mitral regurgitation, is recommended early in the course of the disease to prevent the development of heart failure. Early recognition of mitral regurgitation and timely referral for mitral valve surgery significantly improve symptoms and long-term survival.

Aortic valve bypass for aortic stenosis in a patient with paroxysmal nocturnal hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired bone marrow disorder characterized by hemolytic anemia, neutropenia, thrombocytopenia, hemoglobinuria, and venous thrombosis. Cardiopulmonary bypass-induced complement activation may be associated with exacerbation of hemolysis in patients with PNH undergoing cardiac operations. We describe a 77-year-old man with PNH and critical symptomatic aortic stenosis who underwent successful aortic valve bypass operation without cardiopulmonary bypass as an alternative to conventional aortic valve replacement.