Right ventricle to pulmonary artery conduit: a comparison of long-term graft-related events between bovine jugular vein conduit, aortic homograft, and porcine-valved conduits

Background

The optimal conduit for right ventricle to pulmonary artery (RV-PA) reconstruction does not exist. Reinterventions are common due to conduit stenosis and endocarditis. Tailoring conduit choice according to patients' characteristics could improve the outcomes. The study aimed to compare graft-related events (infective endocarditis, transcatheter pulmonary valve replacement (PVR), transcatheter conduit dilatation, surgical conduit replacement, and transcatheter pulmonary branch intervention for RV-PA reconstruction using bovine jugular vein, aortic homograft, and porcine-valved conduits.

Methods

In a retrospective cohort study, 155 patients with 193 procedures that were done in King Faisal Specialist Hospital and Research Center-Jeddah (KFSHRC JED) for implanting RV-PA conduits from 1999 to 2021 were included. The patients were grouped according to the type of conduit into 3 groups; Group 1 (n=153) received bovine jugular vein (BJVs) grafts, Group 2 (n=29) received aortic homografts, Group 3 (n=11) received porcine-valved conduits. Factors associated with graft-related events were evaluated using stepwise Cox regression analysis.

Results

Patients with BJVs were significantly younger than those with porcine-valved conduits 3 (P=0.009). The weight of BJVs patients was significantly lower than homografts (P=0.002) and porcine-valved conduits patients 3 (P<0.001). The conduit size was as expected significantly lower in BJVs patients than patients who received porcine-valved conduits (P<0.001) and patients who received aortic homografts (P<0.001). There was no difference between Group 2 and 3 (P=0.084). Operative mortality occurred in 13 patients: 12 (7.84%) with BJV conduit and 1 (9.09%) with porcine valved conduit (P=0.351). Male gender [odds ratio (OR): 10.04; 95% confidence interval (CI): 1.28-78.86; P=0.028] and smaller conduit size (OR: 0.78; 95% CI: 0.61-0.99; P=0.048) were associated with increased operative mortality. Freedom from graft-related events at 5 and 10 years was 67% and 52% in BJVs patients, 74% and 36% in patients who received aortic homografts, and 53% in patients who received porcine-valved conduits. Factors associated with increased graft-related events were male gender (HR: 1.58; 95% CI: 1.004-2.50, P=0.048) and younger age (HR: 0.995; 95% CI: 0.991-0.999, P=0.041).

Conclusions

RV-PA reconstruction was associated with low mortality, unrelated to the conduit type. Reinterventions for graft-related events were common. The durability and graft-related events might be comparable among BJV grafts, aortic homografts, and porcine-valved conduits. Factors associated with increased graft-related events in this study were male gender and younger age.

Venovenous malformation: a common finding after Kawashima operation

OBJECTIVES

It has been reported that systemic venovenous malformation (VVM) can develop in patients with interrupted inferior vena cava (IVC) and univentricular type of congenital heart disease who undergo superior vena cava to pulmonary artery connection (Kawashima operation). These malformations can lead to profound systemic desaturation postoperatively. However, there have been few reports that characterise the prevalence, anatomic details and clinical correlations of these systemic VVM arising after Kawashima operation. In this study, we describe our experience with VVM after Kawashima operation, and discuss issues regarding their evaluation and postoperative management.

METHODS

Eight patients with median age 19 months (range: 5-238) who underwent Kawashima operation were subjected to postoperative angiography, prospectively. Sites of VVM origin and entry, as well as their course, were documented. The presence of pulmonary arteriovenous malformations (AVMs) was also documented.

RESULTS

At median follow-up of 31 months (range: 16-72 months), a total of 14 VVM were found in different supra- and infra-diaphragmatic sites in six patients (75%); four of them had concomitant pulmonary AVM while the remaining two patients had only pulmonary AVM.

CONCLUSIONS

Our findings suggest that systemic VVM can occur frequently after Kawashima operation and can produce significant desaturation postoperatively, and hence we support hepatic incorporation. Performing detailed angiographic studies of the supra- and infra-diaphragmatic systemic veins in routine assessment of patients before Kawashima operation is, probably, warranted.

Hemolytic anemia: an unusual presentation of cor triatriatum sinistrum

Cor triatriatum is a congenital malformation of the heart which is usually presented with heart failure. We have dealt with an unusual presentation of a two-month-old child with cor triatriatum presented with hemolytic anemia.

Propranolol: a new indication for an old drug in preventing postoperative junctional ectopic tachycardia after surgical repair of tetralogy of Fallot

Junctional ectopic tachycardia (JET) is a major cause of postoperative morbidity after complete repair of tetralogy of Fallot (TOF). Propranolol is a known medication used in patients with TOF to prevent and control hypercyanotic spells. Despite this, there is little information regarding the relation between preoperative use of propranolol and the incidence of postoperative JET. The aim of this study was to examine the effect of preoperative use of propranolol on the incidence of postoperative JET after full surgical repair of TOF. A retrospective analysis of 109 patients in whom 57 patients received preoperative propranolol (propranolol group) was compared with 52 patients who did not receive propranolol preoperatively (control group). The incidence of postoperative JET was significantly higher in the control group (38%) than the propranolol group (21%) P=0.042. The propranolol group had significantly less mechanical ventilation time, less ICU stay and less total hospital stay than the control group (P<0.05). Our findings suggest that the preoperative use of propranolol may decrease the incidence of JET after full surgical repair of TOF. A prospective randomized study may help to elucidate the exact relationship between the preoperative use of propranolol and the incidence of postoperative JET.

Resternotomy for a retrosternal cardiac pseudoaneurysm in a 1.5-year- old child: a case report

Cardiac pseudoaneurysm is a contained rupture of the myocardium that can occur after cardiac surgery, chest trauma, and endocarditis. The wall of the pseudoaneurysm consists of fibrous tissue and lacks the structural elements found in a normal cardiac wall, and it is contained by the pericardial adhesions or the epicardial wall. Early surgery is recommended even for asymptomatic patients due to the propensity for rupture and fatal outcome. We report our experience with the surgical approach of a child with a cardiac pseudoaneurysm who had undergone a biventricular repair of a double outlet right ventricle with non-committed ventricular septal defect in the form of intraventricular tunneling.

The efficacy and safety of the Amplatzer ductal occluder in young children and infants

BACKGROUND

We have used the Amplatzer ductal occluder for transcatheter closure of large persistently patent arterial ducts, and used our experience to assess the safety and efficacy of the device in young children and infants.

METHODS AND PATIENTS

We used the Amplatzer ductal occluder prospectively in 43 patients with large patent arterial ducts, reviewing our experience to identify any problems or complications.

RESULTS

The procedure proved successful in 42 of the patients. We achieved complete occlusion of the duct in 33 (78.5 per cent) of the patients on the day of insertion. In 6 additional patients, complete occlusion occurred 1 week to 6 months after the procedure. Trivial leaks persisted in 2 patients, while one had a significant residual leak. Problems were encountered in 7 patients. The procedure failed in one, a device was wasted in 2, pulled through in 3, while we experienced kinking of the long Mullins sheath, being unable to retrieve the device, in one patient. Minor complications occurred in 6 patients, finding flow at a peak velocity of 2.2 metres per second in the descending aorta in 2 patients, and at 2.5 metres per second in 2 further patients, and flow at 2.5 metres per second in the pulmonary arteries of two patients. One patient experienced a major complication due to excessive bleeding. Out of the 14 patients suffering adverse events, 13 weighed less than 10 kilograms. This rate of problems and complication in these patients weighing less than 10 kilograms was significantly higher than in the patients weighing more than 10 kilograms.

CONCLUSION

Transcatheter occlusion of moderate to large patent arterial ducts with the Amplatzer ductal occluder device is safe and effective, with a high rate of complete occlusion. Problems and minor complications may be encountered in children weighing less than 10 kilograms. If the device is to be deployed completely in the ductal ampulla, and to avoid descending aortic obstruction, the size of the retention flanges of the occluder should not exceed the largest diameter of the patent arterial duct.

Enalapril does not enhance exercise capacity in patients after Fontan procedure

BACKGROUND

Angiotensin-converting enzyme inhibitors improve exercise capacity in adults with congestive heart failure by decreasing systemic vascular resistance and improving ventricular diastolic function. Patients who have undergone the Fontan procedure have decreased cardiac output, increased systemic vascular resistance, abnormal diastolic function, and decreased exercise capacity compared with normal people.

METHODS AND RESULTS

To test the hypothesis that afterload reduction therapy alters hemodynamic variables and augments exercise capacity in patients after a Fontan procedure, we compared the results of graded exercise with maximal effort from 18 subjects (14.5+/-6.2 years of age, 4 to 19 years after Fontan procedure) in a randomized, double-blind, placebo-controlled crossover trial using enalapril (0.2 to 0.3 mg x kg[-1] x d[-1], maximum 15 mg). Each treatment was administered for 10 weeks. Diastolic filling patterns at rest were assessed by Doppler determination of the systemic atrioventricular valve flow velocity at the conclusion of each therapy. No difference was detected in resting heart rate, blood pressure, or cardiac index. Diastolic filling patterns were also similar. Exercise duration was not different (6.4+/-2.6 [enalapril] versus 6.7+/-2.6 minutes [placebo]). The mean percent increase in cardiac index from rest to maximum exercise was slightly but significantly decreased in subjects after 10 weeks of enalapril therapy (102+/-34% [enalapril] versus 125+/-34% [placebo]; P<.02). At maximal exercise, cardiac index (3.5+/-0.9 [enalapril] versus 3.8+/-0.9 L x min[-1] x m2 [placebo]), oxygen consumption (18.3+/-9 [enalapril] versus 20.5+/-7 mL x min[-1] x kg[-1] [placebo]), minute ventilation (57.5+/-17 [enalapril] versus 55.4+/-19 L/min [placebo]), and total work (247+/-181 [enalapril] versus 261+/-197 W [placebo]) were not different.

CONCLUSIONS

We conclude that enalapril administration for 10 weeks does not alter abnormal systemic vascular resistance, resting cardiac index, diastolic function, or exercise capacity in patients who have undergone a Fontan procedure.