Cardiac surgery simulation: A low-cost feasible option in an Australasian setting

BACKGROUND

Simulation training is a useful adjunct to surgical training and education (SET) in Cardiothoracic Surgery yet training opportunities outside the Royal Australasian College of Surgery or industry-sponsored workshops are rare due to high cost and limited training faculty, time, assessment tools or structured curricula. We describe our experience in establishing a low-cost cardiac simulation programme.

METHODS

We created low-cost models using hospital facilities, hardware stores, abattoirs and donations from industry. Three workshops were conducted on coronary anastomoses, aortic and mitral valve replacement.

RESULTS

Whole porcine hearts were sourced from local farms. Industry donations of obsolete stock were used for suture and valve material-stations constructed using ironing-board, 2-L buckets and kebab-skewers. Suture ring holders were fashioned from recycled cardboard or donated. All participants were asked to complete pre and post simulation self-assessment forms. Across three workshops, 45 participants (57.8% female) with a median age 27 (interquartile range 24-31) attended. Training level consisted of nurses (8, 17.8%), medical students (17, 37.8%), residents/house officers (6, 13.3%) and registrars (14, 31.1%). There were improvements in knowledge of anatomy (mean difference 18%; 95% confidence interval 12%-24%), imaging (16%; 10%-22%) and procedural components (34%; 28%-42%); and practical ability to describe steps (30%; 24%-38%), partially (32%; 26%-38%) or fully complete (32%; 28%-38%) the procedure.

CONCLUSIONS

Simulation-based training in cardiac surgery is feasible in a hospital setting with low overhead costs. It can benefit participants at all training levels and has the potential to be implemented in training hospitals as an adjunct to the SET programme.

Tricuspid valve repair for torrential tricuspid regurgitation after permanent pacemaker lead extraction

Tricuspid regurgitation secondary to percutaneous lead extraction is uncommon, and it rarely requires surgical intervention. Most tricuspid regurgitation occurs during the implantation of tined leads, which can be entrapped in the tricuspid valve apparatus and may require immediate withdrawal. Severe tricuspid regurgitation as a sequela of extracting chronically implanted leads has rarely been reported. Herein, we report a case of torrential tricuspid regurgitation in a 67-year-old woman after the extraction of a permanent pacemaker lead. The regurgitation was confirmed on transesophageal echocardiography during lead extraction, and the tricuspid valve was successfully repaired with suture bicuspidization of the valve and the support of ring annuloplasty. A short review of the relevant literature follows the case report.

EXPERIENCE WITH UNIPOLAR RADIOFREQUENCY ABLATION FOR ATRIAL FIBRILLATION

BACKGROUND

The cut and sew Cox maze procedure for atrial fibrillation (AF), although effective, is not widely used because of technical complexity, prolonged duration and significant risk of postoperative bleeding. This study reviews our experience with the unipolar radiofrequency ablation (RFA) procedure, which was used to create a modified maze to treat AF.

METHODS

A retrospective review of 31 patients undergoing consecutive cardiac surgery who had concomitant RFA for AF over a 16-month period was carried out. A Cobra unipolar RFA probe (EPT; Boston Scientific, San Jose, CA, USA) was used to create a standard set of lesions.

RESULTS

There were 20 men and 11 women (mean age, 66 +/- 9 years; range, 48-87 years). AF was continuous in 21 patients and intermittent in 10. The median duration of AF leading up to surgery was 48 months (range, 6 months-20 years). Left atrium was enlarged in 81% of the patients. Operations included mitral valve repair (7 patients), replacement (5), coronary artery bypass (10), aortic valve replacement (1) and combined procedures (8). There were no complications directly attributable to RFA. There were three early deaths. One patient required a permanent pacemaker. Median follow up was 22 months (range, 12-30 months). One patient died 2 years after the operation from a stroke. Cardioversion was attempted in five patients within 3 months of operation and was successful in four. At 2 years following the procedure, the probability of the patient remaining in sinus rhythm was 0.71 +/- 0.15.

CONCLUSION

Surgical RFA can be carried out as a useful adjunct to conventional cardiac surgery. Although the results were satisfactory in this series, further studies are needed to refine the indication of the procedure and to assess its longer-term efficacy.

URGENT AND EMERGENCY CORONARY ARTERY BYPASS GRAFTING FOR ACUTE CORONARY SYNDROMES

BACKGROUND

Urgent and emergency coronary artery bypass grafting may be associated with significant mortality and morbidity. We report our recent experience with this group of patients.

METHODS

A retrospective analysis of 441 patients undergoing urgent and emergency surgery over a 3-year period was carried out. Multivariate analysis was used to identify subgroups of patients who were most at risk of death.

RESULTS

The 30-day mortality was 3.3 and 16.3% in the urgent and emergency groups, respectively. Urgent surgery was associated with significantly shorter duration of ventilation (16 h vs 69 h) and stay at the intensive care unit (31 h vs 102 h). The incidence of pneumonia, pulmonary embolism, renal failure and neurological events were also less in the urgent group. The preoperative use of the intra-aortic balloon pump was low (0.8% in the urgent group and 4.8% in the emergency group). Multivariate analysis showed that patients over 70 years of age (odds ratio 3.2, 95% confidence interval 1.1-9.5) with left main stenosis (odds ratio 4.4, 95% confidence interval 1.5-12.4) complicated by cardiogenic shock (odds ratio 17.8, 95% confidence interval 5.2-61.1) were at highest risk of death. Patients transferred directly to theatre from cardiac catheter laboratory following failed percutaneous interventions were found to be most at risk. Mortality in this group was 29%, with 50% patients being in shock and 36% having left main stenosis.

CONCLUSION

Satisfactory results have been obtained in urgent coronary artery bypass grafting, but acute coronary syndromes complicated by cardiogenic shock remain a high-risk group. Further studies are needed to define the optimal operative management in this group of patients.

Retroaortic course of the anomalous left main coronary artery: is it a benign anomaly? A case report and review of literature

BACKGROUND

Left coronary artery sharing a common origin with the right coronary artery and taking a retroaortic course is a rare coronary anomaly. It has been considered a benign entity.

CASE REPORT

We report a 19-year-old man who presented with chest pain. Cardiac enzymes were elevated suggesting myocardial ischaemia. Coronary angiography revealed single origin of the coronary artery in the right coronary sinus. The left main coronary artery followed a retroaortic course before bifurcating. The anomalous left coronary artery was dissected and reimplanted in the left coronary sinus. The patient made an uneventful recovery. One year later, he is well with no recurrence of symptoms.

CONCLUSIONS

Surgery to restore the normal anatomic position of the left coronary ostium is advisable whenever this anomaly is discovered.

Atrial myxoma with coexistent coronary artery disease: a report of two cases

The age at presentation and the symptoms of atrial myxomas and coronary artery disease can be similar. At times, the two lesions coexist. Operative strategy needs to be carefully planned when combined surgical treatment is contemplated. In the present paper, two cases of concomitant atrial myxoma and atherosclerotic coronary artery disease are reported. The first patient had a left atrial myxoma with triple-vessel coronary artery disease. The other had a right atrial myxoma and needed two bypass grafts. Both patients had a satisfactory outcome.

Use of a single silastic chest drain following thoracotomy: initial evaluation

BACKGROUND

It is standard practice to use multiple large bore semi-rigid chest tubes to drain the pleural cavity following thoracic procedures. These can cause pain and discomfort at the insertion site.

METHODS

We describe our experience with the use of a single small silastic drain following thoracotomy. From November 2001 to November 2003, size 19-F silastic chest tubes (Blake drains) were used for drainage of the pleural cavity in 37 patients at our institution. The patients ranged in age from 18 to 81 years (mean 65). The operations included 22 lobectomies, two bilobectomies, 10 wedge resections, and three other procedures.

RESULTS

Total drainage in each patient ranged from 420 to 5440 mL (mean 1387 mL). Tubes were left in place for an average of 4.3 days (range 1-12). The average postoperative length of stay was 7.6 days (range 3-44, median 5). Three patients required insertion of an additional tube for dislodgement, persistent air leak, and bronchopleural fistula, respectively. These complications occurred among the first 15 patients in the present series. None of the patients had persistent pleural effusion. Subjectively, these tubes were more comfortable for the patients and were easier to remove.

SUMMARY

The use of a single, small silastic chest drains following thoracotomy may be safe and effective in draining both fluid and air, though an additional tube may be necessary for persistent leaks.

Follow-up of Australian Aboriginal Patients Following Open-Heart Surgery in Western Australia

BACKGROUND

To date there has been only one published report pertaining to the outcomes following open-heart surgery in Australian aboriginal patients.

METHODS

The records of 57 consecutive aboriginal patients who underwent open-heart surgery at our institution over a 6-year period were retrospectively reviewed. Attempts were made to contact the patient by telephone, by letter, through their listed next of kin, general practitioners, community nurse or through the aboriginal liaison officer.

RESULTS

There were 38 males and 19 females. Forty-five patients had coronary artery bypass grafting, 10 had isolated valve procedures while 2 had a combined operation. Mechanical prostheses were used for all valve replacements. There was a high incidence of diabetes, hypertension, hypercholesterolemia and smoking. There was one hospital death. Follow-up ranged from 6 months to 6 years with a mean of 3.09 years. Forty-four of the 56 (78.6%) hospital survivors were contactable while 21.4% were not contactable. There were two late deaths. Of the coronary patients who could be contacted, only 79% were taking Aspirin and a similar number Statin. 23% patients had recurrence of angina. There were five episodes of anticoagulation related complications in three patients. Only 44% of the patients were conversant with anticoagulation.

CONCLUSIONS

The follow-up of the aboriginal patients was disappointing. The compliance with the medications was sub-optimal. There was a high incidence of recurrence of angina and anticoagulation related complications. The results raise concern about the use of mechanical prosthesis in these patients.

Functional tricuspid regurgitation secondary to aortic annular abscess: An unusual presentation of infective endocarditis

An unusual case of aortic annular abscess is presented, in which the patient presented with features of gross tricuspid regurgitation. There was no direct involvement of the tricuspid valve. Tricuspid regurgitation disappeared following surgical repair of the annular abscess. The present case also illustrates the utility of trans-oesophageal echocardiography in establishing the diagnosis and planning surgical intervention.

Intraaortic balloon pumping in children

BACKGROUND

Intraaortic balloon pump (IABP) usage in young children remains a rarity because, first, there is a widespread misconception that the greater elasticity of the aorta in children may prevent effective augmentation, and second, children in low cardiac output states are more likely to have associated right ventricular failure and pulmonary problems. We report our experience with the use of IABP in children undergoing cardiac surgery in whom mechanical support was necessary for the treatment of refractory cardiac failure.

METHODS

Over a 3-year period, 14 children were identified as requiring IABP support after cardiac surgery. Their median age was 3 years (range 7 days to 13 years) and their median weight was 13.3 kg (range 3.5-51 kg). Indications for IABP use were: failure to wean from cardiopulmonary bypass (5 patients), sudden deterioration in intensive therapy unit (ITU) (3 patients), progressive deterioration in ITU (4 patients), and prophylactic therapy for known poor preoperative ventricular function (2 patients).

RESULTS

Ten of 14 patients (71%) were successfully weaned from the IABP, of whom 8 became long-term survivors (57%). Among the survivors, the mean duration of IABP usage was 127 h (range 12-260 h), while for those who died while on IABP, the mean duration was 15 h (range 8-24 h). The most major IABP-related complication encountered was mesenteric ischemia, which had a fatal outcome.

CONCLUSIONS

IABP therapy, used as an adjunct to conventional medical treatment, can give properly selected young children in refractory low cardiac output states after heart surgery a greater than 50% chance of long-term survival.

Retrosternal fat pad for prevention of suppurative sternitis

An increased incidence of postoperative sternal infection has been reported after the use of bilateral internal mammary arteries for coronary artery grafting. In this series, a pedicled pericardial fat pad was mobilized to lie in the retrosternal space before the sternum was approximated. This technique was used in 101 consecutive patients who underwent coronary artery grafting using bilateral internal mammary arteries. Twenty-four percent of the patients were diabetic. No suppurative sternitis developed in any of these patients.

The clinical profile and surgical treatment of tetralogy of Fallot in the adult: results of repair in 200 patients

This report describes our 17-year experience with intracardiac repair in 200 patients older than 14 years with tetralogy of Fallot. Congestive failure, hemoptysis, and cerebral abscess were present in 15, 10, and 3% of patients, respectively. Prior palliative shunts had been performed in 24.5% only. Polycythemia with a hematocrit greater than 60% was noted in 100 patients but was not considered an incremental risk factor (p greater than 0.05). A transannular gusset was utilized in 74% of patients in the last 5 years of the study. Hospital mortality was 1.3% in the last 5 years. Ninety-seven percent of survivors at follow-up are asymptomatic and leading an active life. Recatheterization data from 86 patients revealed excellent or good results in 88%. The incidence of residual ventricular defect was 1% overall, with a zero incidence in the last 12 years. On the basis of this review, we consider that easier and hemodynamically satisfactory repair has been achieved in the adolescent and older patient compared with the child. The ultimate longevity, however, must await the results of long-term functional and serial hemodynamic evaluation.