SLC3A1 and SLC7A9 mutations in autosomal recessive or dominant canine cystinuria: a new classification system.

BACKGROUND: Cystinuria, one of the first recognized inborn errors of metabolism, has been reported in many dog breeds. HYPOTHESIS/OBJECTIVES: To determine urinary cystine concentrations, inheritance, and mutations in the SLC3A1 and SLC7A9 genes associated with cystinuria in 3 breeds. ANIMALS: Mixed and purebred Labrador Retrievers (n = 6), Australian Cattle Dogs (6), Miniature Pinschers (4), and 1 mixed breed dog with cystine urolithiasis, relatives and control dogs. METHODS: Urinary cystinuria and aminoaciduria was assessed and exons of the SLC3A1 and SLC7A9 genes were sequenced from genomic DNA. RESULTS: In each breed, male and female dogs, independent of neuter status, were found to form calculi. A frameshift mutation in SLC3A1 (c.350delG) resulting in a premature stop codon was identified in autosomal-recessive (AR) cystinuria in Labrador Retrievers and mixed breed dogs. A 6 bp deletion (c.1095_1100del) removing 2 threonines in SLC3A1 was found in autosomal-dominant (AD) cystinuria with a more severe phenotype in homozygous than in heterozygous Australian Cattle Dogs. A missense mutation in SLC7A9 (c.964G>A) was discovered in AD cystinuria in Miniature Pinschers with only heterozygous affected dogs observed to date. Breed-specific DNA tests were developed, but the prevalence of each mutation remains unknown. CONCLUSIONS AND CLINICAL IMPORTANCE: These studies describe the first AD inheritance and the first putative SLC7A9 mutation to cause cystinuria in dogs and expand our understanding of this phenotypically and genetically heterogeneous disease, leading to a new classification system for canine cystinuria and better therapeutic management and genetic control in these breeds.

Early discharge after coronary artery bypass graft surgery: are patients really going home earlier?

OBJECTIVE: This study was undertaken to determine whether early discharge after coronary artery bypass grafting allows patients to return home earlier or merely increases the use of outpatient nursing and inpatient rehabilitation services. METHODS: Patterns of discharge were analyzed in 407 patients undergoing bypass grafting in 1990, when there were no early extubations or fast track protocols, and compared with 379 patients in 1998, when these protocols were used. RESULTS: Patients in 1998 had a higher prevalence of class IV angina (35.3% vs 22.8%; P =.006), urgent/emergency surgery (58.3% vs 44.9%; P =.015), and lower ejection fractions (48.9% +/- 16.4% vs 52.9% +/- 13.5%; P =.0002). Despite these increased risk factors, 1998 patients spent less time receiving ventilatory support (10.2 +/- 9.2 vs 26.7 +/- 15.7 hours; P <.001) and had a shorter length of stay (5.4 +/- 2.5 vs 9.2 +/- 4.3 days; P <.001). However, fewer 1998 patients were discharged home (56.7% vs 97.0%; P <.0001). A higher percentage of 1998 patients (43.3% vs 2.9%; P <.00001) were discharged to extended care facilities where their average length of stay was 10.6 +/- 15.1 days. Readmission to the Boston Medical Center was also more common in 1998 patients (5.3% vs 0.5%; P <.0001). CONCLUSIONS: Early extubation and fast track protocols have resulted in earlier discharge from acute care facilities. However, the anticipated earlier return to home has been offset by the increased use of outpatient nursing services, discharges to extended care facilities, and hospital readmissions.

Improved clinical outcomes after operation of the proximal aorta: a 10-year experience.

BACKGROUND: This study evaluated the impact of recent advances (particularly noninvasive diagnosis, retrograde cerebral perfusion, heparin-bonded circuits, and use of collagen-impregnated grafts and antifibrinolytic agents) on clinical outcomes of patients undergoing proximal aortic operations. METHODS: One hundred eight consecutive patients undergoing 111 proximal aortic operations over 10 years were studied. The cohort was divided into two groups: early, 1987 to 1993 and late, 1994 to 1997. RESULTS: Baseline patients profiles, indications for operation (aneurysm, 66 patients; dissection, 45 patients), priority of the operation, and surgical procedures were comparable for both groups. Mortality and morbidity for the entire cohort were 13.5% (15 of 111) and 66% (73 of 111), respectively. Compared with the early group, the late group was characterized by significantly higher use of noninvasive diagnostic modalities (69% versus 10%), exclusive use of heparin-bonded circuits and collagen-impregnated grafts (100% versus 0% for both), use of antifibrinolytic agents (79% versus 8%), and the introduction of retrograde cerebral perfusion (43% versus 0%) (p<0.00001 for all). These changes in practice were associated with a substantial decrease in operative mortality (26% [13 of 49] versus 3% [2 of 62], p = 0.001), overall morbidity (77% [38 of 49] versus 56% [35 of 62], p = 0.02), blood transfusions (55.6+/-48 donor units versus 29.3+/-35 donor units, p = 0.003), and a shorter hospital stay (21.6+/-31 days versus 12.1+/-15 days, p = 0.07). Average long-term follow-up for 99% (107 of 108) of patients was 29.6+/-30 months (1 to 120 months). Ten-year actuarial survival was 57.3%+/-8% with 93% being in New York Heart Association functional class I or II. CONCLUSIONS: Recent advances, particularly noninvasive diagnosis and improved operative management, have led to a substantial reduction in mortality and morbidity after proximal aortic operation. Improved short- and long-term outcomes were achieved both in acute dissection and aneurysm procedures, although patients remain at risk for long-term distal aortic complications.

Minimally invasive cardiac valve surgery.

With the recent advancement and experience in minimally invasive coronary artery bypass surgery in selected patients, minimally invasive valve surgery using similar techniques is promising. Coupled with the movement in cardiac surgery to decrease costs, hospital lengths of stay and recovery time, minimally invasive techniques for both mitral and aortic valve surgery are promptly being pursued. This article reviews various minimally invasive surgical techniques for mitral and aortic valve surgery. Mitral valve surgery by means of port-access technology is detailed. Techniques for minimally invasive aortic valve surgery via a ministernotomy and a parasternal incision are described.

Repair of left ventricular aneurysm: long-term results of linear repair versus endoaneurysmorrhaphy.

BACKGROUND: Recently, endoaneurysomorrhaphy has been proposed as a more physiologic repair of postinfarction left ventricular aneurysm than is linear repair. There are only a few studies comparing the short-term and long-term results of the two techniques. METHODS: Clinical outcomes and echocardiographic measurements of left ventricular volume and sphericity in 27 patients who underwent endoaneurysmorrhaphy were compared with those in 20 patients who had linear repair. RESULTS: The two groups were matched with respect to age, gender, comorbid risk factors, functional class, urgency of the operation, and concomitant procedures. Preoperatively, left ventricular ejection fraction was lower in the endoaneurysmorrhaphy group (0.25 +/- 0.08 versus 0.30 +/- 0.09; p = 0.03). Follow-up was available in 44 patients (94%) and ranged from 2 to 86 months (mean, 41.0 +/- 26.5 months). Thirty-day operative mortality, perioperative complications, 5-year survival, and freedom from cardiac death were similar. Early postoperative percentage increase in left ventricular ejection fraction was greater after endoaneurysmorrhaphy (0.51 +/- 0.64 versus 0.18 +/- 0.48; p = 0.036). Long-term functional improvement was significantly better in the endoaneurysmorrhaphy group: At the time of last follow-up, 88% of patients were in New York Heart Association class I/II, compared with 53% after linear repair (p = 0.01). There were no measurable differences between the groups with respect to left ventricular ejection fraction (0.28 +/- 0.11 versus 0.27 +/- 0.11; p = 0.90), left ventricular volume (171.6 +/- 59.1 versus 169.9 +/- 54.4 mL; p = 0.94), and sphericity index (0.61 +/- 0.09 versus 0.61 +/- 0.12; p = 1.0). CONCLUSIONS: Despite having a similar effect on left ventricular geometry, endoaneurysmorrhaphy resulted in a greater increase in postoperative left ventricular ejection fraction and a substantially improved long-term clinical outcome.

Current perspectives on prosthetic heart valves and valve repair.

The quest for the ideal cardiac valve substitute represents a highly categorized goal for the cardiac surgical community. Ongoing research has resulted in the development and creation of multiple newer heart valves and techniques for valve repair. Each of the many valves commercially available possesses a wide array of features. With the expansion of research investigations, improvement in long-term management can be translated and incorporated directly into patient care. As valvular replacement and repair/reconstruction surgery become more commonplace, it is paramount for nurses to be knowledgeable regarding the critical components of care.