Absent right superior vena cava and persistent left superior vena cava in a patient with bicuspid aortic valve with aortic stenosis

Persistent left superior vena cava (LSVC) with absent right SVC (RSVC) is a rare congenital anomaly. If undetected, the condition may pose difficulties in central venous catheter insertion, pacemaker electrode insertion, and cannulation during cardiopulmonary bypass. We describe a case of persistent LSVC with absent RSVC, who was diagnosed to have bicuspid aortic valve with aortic stenosis.

Cardiac surgery at high altitude.

Eleven children between 4 and 17 years of age underwent ligation of a patent ductus arteriosus during two medical camps in September 2003 and August 2004 at the Sonam Norboo Memorial District Hospital at Leh, Ladakh (11,400 feet above mean sea level). These children had a low mean arterial oxygen saturation while breathing room air. They were all acclimatized to high altitude. Surgery was performed under general anaesthesia with endotracheal intubation. Patients were extubated on the table. All children survived the operation and were discharged within 5-6 days following surgery. No surgical or anaesthetic complications were encountered. Simple cardiac surgical procedures such as ligation of a patent ductus arteriosus can be performed safely at high altitudes.

Anticoagulation protocol and early prosthetic valve thrombosis.

BACKGROUND: [corrected] Prosthetic valve thrombosis is a major cause of morbidity and mortality following heart valve replacement with a mechanical valve. METHODS AND RESULTS: 538 patients who underwent mechanical valve replacement between April 1999 and June 2003 were included in the study. They were divided into two groups. Group A (n=245) consisted of patients who underwent mechanical valve replacement between April 1999 and June 2001. Anticoagulation was started on the first post-operative day and consisted of only oral nicoumalone. Group B (n=293) consisted of patients who underwent mechanical valve replacement between July 2001 and June 2003; enoxaparin was started six hours following surgery in addition to oral nicoumalone which was started on first post-operative day. Fifteen (6.1%) patients in group A developed early prosthetic valve thrombosis at an interval of 4.33+/-0.97 months (range 3-6 months) following surgery. Ten had prosthetic valve thrombosis in the mitral position and five had prosthetic valve thrombosis in the aortic position. In group B, six (2.1%) patients developed early prosthetic valve thrombosis at a median interval of 4.58+/-0.9 months (range 3.5-6 months) in the mitral position (p=0.01). CONCLUSIONS: Addition of enoxaparin to the anticoagulation regime in the immediate post-operative period significantly reduces early prosthetic valve thrombosis.

Mitral valve repair for nonrheumatic mitral regurgitation.

BACKGROUND: We studied the results of mitral valve repair in patients with severe mitral regurgitation of nonrheumatic etiology. METHODS AND RESULTS: Between January 1988 and April 2002, 116 patients, of which 59 were male and 57 female, with severe mitral regurgitation of nonrheumatic etiology, underwent mitral valve repair using a variety of techniques. Their mean age was 26.4 years (range 2-67 years). The cause of mitral regurgitation was congenital in 56 patients, myxomatous in 44, infective endocarditis in 7, and ischemic in 9. Ninety patients were in preoperative New York Heart Association class III, and 26 in class IV. Reparative procedures included posterior teflon felt collar annuloplasty (modified Cooley's) in 80 patients, chordal shortening in 37, cusp excision in 34, cleft closure in 8, chordal transfer in 6, and neochordae in 3. The early mortality was 3.4% (4 patients). Follow-up ranged from 1 to 167 months (mean 47 months), and was 95% complete. There were 2 late deaths (1.7%). Six patients (5.2%) underwent reoperation for severe mitral regurgitation post-repair. Of the remaining 104 patients, 90 (86.5%) had no or trivial mitral regurgitation at the last follow-up. Actuarial, reoperation-free, and event-free survival at 130 months was 93%+/-3.6%, 89.9%+/-6%, and 69.7%+/-13.7%, respectively. Ninety-two patients (88.5%) were in New York Heart Association class I at the last follow-up. CONCLUSIONS: Mitral valve repair in nonrheumatic mitral regurgitation patients provides satisfactory results with current surgical techniques, and is the preferred option in this subset of patients.

Autologous right atrial patch for closure of atrial septal defect.

BACKGROUND: Prosthetic or pericardial patches used for the closure of atrial septal defects are associated with infrequent but definite problems. As an alternative, we used a right atrial free-wall patch in 12 patients, 7-54 years of age. METHODS AND RESULTS: The presence of a large secundum atrial septal defect (n=2). associated mitral valve regurgitation (n=7), primum atrial septal defect (n=2) and sinus venosus defect (n=1) necessitated the use of a patch. The mitral valve was repaired in 9 patients (including 2 with a primum defect). One patient with a primum defect who was in congestive heart failure preoperatively died after 3 weeks due to refractory ventricular fibrillation. The remaining patients were discharged 5 to 7 days post procedure. No flow was detected across the septal patch on predischarge echocardiography. One patient underwent reoperation for failed mitral valve repair one month postprocedure. At reoperation, the patch was found to be intact with normal texture and without any suture dehiscence. Histopathological examination of the explanted patch revealed viable endothellum and subendothelial muscle on both surfaces of the patch. Follow-up ranged from 6 to 36 months. Echocardiography performed after 6 to 32 months post procedure showed an intact patch with no residual defect. All the patients are in sinus rhythm. Holter monitoring performed in 6 patients was normal in all of them. Electrophysiological study was performed in 2 patients using a mapping catheter 4 and 6 months post-procedure, respectively, and recorded normal atrial potentials from the site of the patch. CONCLUSIONS: The use of an autologous free right atrial wall as a patch for atrial septal defect closure is a viable option.