Does cardiac resynchronisation therapy improve survival and quality of life in patients with end-stage heart failure?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether bi-ventricular pacing, also referred to as cardiac resynchronisation therapy (CRT), improves survival and quality of life in patients with severe (NYHA III/IV) symptomatic heart failure. Cardiac pacing can be achieved by stimulation of the right ventricle, left ventricle (LV) or by bi-ventricular pacing. This best evidence topic considers only bi-ventricular pacing. This involves placement of pacing leads in the right ventricle, epicardially on the LV with a lead typically placed in a branch of the coronary sinus and, unless the patient is in permanent atrial fibrillation, in the right atrium. Bi-ventricular pacing allows the optimisation of atrio-ventricular timing and resynchronisation of septal and postero-lateral left ventricular contraction. Symptomatic heart failure has a high morbidity and a poor prognosis. Patients with dyspnoea at rest or on minimal exertion (NYHA III/IV) are at high risk of death due to progressive heart failure, while those with less severe symptoms are more likely to experience sudden cardiac death. Up to 50% of patients with NYHA class III/IV symptoms have a prolonged QRS duration (>120 ms) on 12-lead ECG (usually in a LBBB pattern). This intra-ventricular conduction delay is a surrogate marker of mechanical dyssynchrony (an uncoordinated regional contraction-relaxation pattern) and is associated with reduced cardiac output and increased mortality. Bi-ventricular pacing can reduce the delay in activation of the LV free wall found in many patients with LV systolic dysfunction, thereby improving mechanical synchrony and cardiac output. It may also reduce pre-systolic mitral regurgitation. Three hundred and fifty-six papers were identified using the search method outlined, nine randomised controlled trials and a meta-analysis in addition to published guidelines presented the best evidence to answer the clinical question. Current best available evidence suggests that in patients with left ventricular systolic dysfunction (LVEF or=120 ms), and NYHA class III or IV symptoms despite optimal pharmacological therapy, bi-ventricular pacing significantly reduces the number of hospitalisations from heart failure, improves functional status (NYHA class, peak oxygen uptake and exercise tolerance) and improves health related quality of life. The CARE-HF study also demonstrated a reduction in mortality from progressive heart failure and all-cause mortality.     

Treatment with bone marrow-derived stromal cells accelerates wound healing in diabetic rats

Bone marrow stem cells participate in tissue repair processes and may have a role in wound healing. Diabetes is characterised by delayed and poor wound healing. We investigated the potential of bone marrow-derived mesenchymal stromal cells (BMSCs) to promote healing of fascial wounds in diabetic rats. After manifestation of streptozotocin (STZ)-induced diabetic state for 5 weeks in male adult Sprague-Dawley rats, healing of fascial wounds was severely compromised. Compromised wound healing in diabetic rats was characterised by excessive polymorphonuclear cell infiltration, lack of granulation tissue formation, deficit of collagen and growth factor [transforming growth factor (TGF-beta), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), platelet-derived growth factor PDGF-BB and keratinocyte growth factor (KGF)] expression in the wound tissue and significant decrease in biomechanical strength of wounds. Treatment with BMSC systemically or locally at the wound site improved the wound-breaking strength (WBS) of fascial wounds. The improvement in WBS was associated with an immediate and significant increase in collagen levels (types I-V) in the wound bed. In addition, treatment with BMSCs increased the expression of growth factors critical to proper repair and regeneration of the damaged tissue moderately (TGF-beta, KGF) to markedly (EGF, VEGF, PDGF-BB). These data suggest that cell therapy with BMSCs has the potential to augment healing of the diabetic wounds.     

Effects of radiation therapy on pedicled transverse rectus abdominis myocutaneous flap breast reconstruction

Radiotherapy is being increasingly used in the treatment of breast cancer after breast conservation as well as after total mastectomy. The effect of radiation on pedicled transverse rectus abdominis myocutaneous (TRAM) flap reconstruction is examined. A retrospective review of 199 patients undergoing 232 pedicled TRAM flap reconstructions was performed to identify patients who received radiotherapy. Patients were stratified into 5 groups by the use and timing of radiation as well as the timing of the reconstruction. The overall esthetic appearances were assessed by blinded reviewers. The incidence of flap complications was 34.2% in the immediate nonirradiated group, 10.7% in the delayed nonirradiated group, 44% in the post-TRAM radiation group, 60% in the immediate pre-TRAM radiation group, and 33% in the delayed pre-TRAM radiation group (P = 0.010). Patients who had immediate TRAM flap reconstruction and did not receive radiation had a better global esthetic outcome (P < 0.001) than the other 4 groups. The esthetic outcome was similar whether radiation was administered pre- or post-TRAM flap reconstruction. Radiation therapy has a deleterious effect on the esthetic outcome of pedicled TRAM flap reconstruction whether administered before or after reconstruction. There was no difference in TRAM flap complications in any of the groups that received radiation therapy.     

Evaluation of abduction range of motion and avoidance of inferior scapular impingement in a reverse shoulder model

The purpose of this study was to determine the effects of prosthetic design and surgical technique of reverse shoulder implants on total abduction range of motion and impingement on the inferior scapular neck. Custom implants in three glenosphere diameters (30, 36, and 42 mm), with 3 different centers of rotation offsets (0, +5, and +10 mm), were placed into a Sawbones scapula (Pacific Research Laboratories, Vashon, WA) in 3 different positions: superior, center, and inferior glenoid. Humeral sockets were manufactured with a 130 degrees , 150 degrees , and 170 degrees neck-shaft angle. Four independent factors (glenosphere diameter, center of rotation offset, glenosphere position on the glenoid, and humeral neck-shaft angle) were compared with the 2 dependent factors of range of motion and inferior scapular impingement. Center of rotation offset had the largest effect on range of motion, followed by glenosphere position. Neck-shaft angle had the largest effect on inferior scapular impingement, followed by glenosphere position. This information may be useful to the surgeon when deciding on the appropriate reverse implant.     

Unstable elbow dislocations

Seventeen patients with a posterior dislocation of the elbow and either no fracture or a minimal capsuloligamentous avulsion fracture were treated operatively for persistent redislocation after manipulative reduction. Fifteen had open reduction and ligament repair (3 with ancillary hinged external fixation), and 2 infirm patients had closed reduction and cross pinning of the elbow joint. Among the 12 patients treated with ligament repair alone, 1 redislocated (treated with a second surgery for hinged external fixation) and 4 had residual subluxation (treated with temporary casting of protected active exercises) after ligament repair alone (42% residual instability). A concentric, stable elbow was eventually achieved in all 17 patients. The average flexion arc was 113 degrees . The average Broberg and Morrey score was 88, with 3 excellent, 10 good, and 2 fair results. A small percentage of elbow dislocations require operative treatment. Ligament repair alone may not be sufficient, and protection with a hinged external fixator is recommended.     

Subscapularis function after total shoulder replacement: results with lesser tuberosity osteotomy

Until recently, little consideration was placed on the integrity of the subscapularis tendon after total shoulder arthroplasty. We have noted that several of our patients exhibited loss of internal rotation strength and subscapularis function after total shoulder arthroplasty utilizing an anatomic soft tissue repair of the subscapularis, both with and without bone tunnels. On the basis of those results, we began removing the subscapularis with a small piece of bone by a lesser tuberosity osteotomy in an attempt to achieve improved subscapularis function through bony healing at the repair site. A retrospective review of 28 patients (30 shoulders) was done of patients who had total shoulder arthroplasty performed between 2001 and 2003. The lesser tuberosity and attached subscapularis were repaired through bone tunnels in all cases. The mean follow-up was 1.1 years. Terminal internal rotation was evaluated by the belly-press examination. Subscapularis function was assessed by the patient's ability to tuck in a shirt behind the back, and 25 of 30 patients (83.3%) reported no difficulty. Belly-press examination results were normal in 18 of 30 patients (60%). Removal of the subscapularis through a lesser tuberosity osteotomy results in reliable restoration of internal rotation strength after total shoulder arthroplasty, as measured by the ability to perform a stomach press and to tuck in a shirt. In comparing these results with our earlier cohort of patients with similar demographics and postoperative rehabilitation that had soft tissue repair, improved results were seen in the group that underwent lesser tuberosity osteotomy.     

Newborn and toddler intestinal obstruction owing to congenital mesenteric defects

Transmesenteric hernia is a rare cause of intestinal obstruction most commonly affecting the small bowel. The mesenteric defect is usually 2 to 3 cm in diameter. The authors describe 2 cases of young pediatric patients presenting with bowel obstruction resulting from a congenital mesenteric defect. The initial patient had a 30-cm-wide congenital defect in the ileal mesentery through which the sigmoid colon and some loops of small bowel had herniated. The second patient is a newborn infant who presented with symptoms and radiographic evidence of proximal bowel obstruction initially thought to be resulting from malrotation with midgut volvulus but was found at surgical exploration to have a small defect in the ileal mesentery.