Bipolar Versus Unipolar Temporary Epicardial Ventricular Pacing Leads Use in Congenital Heart Disease: A Prospective Randomized Controlled Study.

BACKGROUND: To compare the pacing parameters of unipolar versus bipolar temporary ventricular epicardial pacing leads. DESIGN: Prospective Randomized Unblinded Controlled Study. PATIENTS AND METHODS: Fifty patients undergoing surgery for congenital heart disease who were anticipated to require temporary ventricular pacing leads were recruited preoperatively: 25 patients were randomized to receive unipolar temporary ventricular epicardial pacing leads; the remaining 25 were randomized to receive bipolar temporary ventricular epicardial leads. The baseline characteristics of the groups were similar. The pacing parameters were measured daily for up to first seven postoperative days (PODs) with the day of surgery recorded as POD 0. RESULTS: On the day of insertion, the mean pacing and sensing thresholds were similar for both unipolar and bipolar leads. Thresholds progressively deteriorated with each subsequent POD. By POD 4, the mean ± standard deviation pacing threshold of ventricular bipolar lead was 2.87 ± 0.37 mA compared with 5.6 ± 0.85 mA for the unipolar leads (P = 0.005). The decrease in sensing threshold of the unipolar ventricular pacing leads was significantly more than that of bipolar leads (by POD 5, 5.7 ± 2.64 vs 10.33 ± 2.8, P = 0.01). CONCLUSIONS: Our study shows that the bipolar leads (Medtronic 6495, Medtronic Inc., Minneapolis, MN, USA) have superior sensing and pacing thresholds in the ventricular position in patients undergoing surgery for congenital heart disease when compared to the unipolar leads (Medical Concepts Europe VF608ABB, Medical Concepts Europe Inc., Buffalo, NY, USA).

Retrospective Cohort Study Comparing Redo Operations Using Ferromagnetic Dissection and Conventional Monopolar Dissection.

Purpose To evaluate effectiveness of a novel hemostatic dissection tool in patients with congenital heart disease undergoing redo pericardiac dissections. Description This dissection tool employs ferromagnetic energy to cut and coagulate. The unit passes no electric current through the patient, thus eliminating cautery-induced dysrhythmias and electrical interference. Ferromagnetic dissection is precise and reduces thermal injury spread by as much as 90%. Evaluation We case matched 22 patients undergoing reoperation for congenital heart surgery by weight/operation. Group 1 used the ferromagnetic tool, and Group 2 used conventional monopolar cautery for pericardiac dissection. For groups 1 and 2, the mean weight was 27.7 and 28.4, respectively (P = .87). Time (minutes) from skin incision to cardiopulmonary bypass was 71 versus 72 (P = .44), cardiopulmonary bypass (minutes) was 75.6 versus 73.6 (P = .42), total operative time (minutes) was 193 versus 201 (P = .34). Chest tube output/kilogram in first 6 and first 24 hours was 0.4 versus 1.3 (P = .02) and 0.8 versus 2.4 (P = .01) for groups 1 and 2, respectively. Re-exploration for bleeding was 0% versus 9% (P = .07). There was no mortality. Conclusion The ferromagnetic dissection system appears safe and efficacious. Bleeding was significantly decreased and the need for re-exploration reduced.

Temperature and Neurologic Outcomes in Neonates Undergoing Cardiac Surgery: A Society of Thoracic Surgeons Study.

BACKGROUND: There is significant variability in postoperative neurological injury rates in patients with congenital heart disease, with early injuries impacting long-term neurodevelopmental outcomes; therefore, there is an urgent need for identifying effective strategies to mitigate such injuries. OBJECTIVES: This study aims to assess the association between nadir intraoperative temperature (NIT) and early neurological outcomes in neonates undergoing congenital heart surgery. METHODS: Analyzing data from 24,345 neonatal cardiac operations from the Society for Thoracic Surgeons Congenital Heart Surgery Database between 2010 and 2019, NIT was assessed using a mixed-effect logistic regression model, targeting major neurological injury (stroke, seizure, or deficit at discharge) as a primary endpoint. RESULTS: The study observed a shift from hypothermic circulatory arrest to cerebral perfusion with an increase in mean nadir temperature from 23.9 °C to 25.6 °C (P < 0.0001). Major neurological injury was noted in 4.9% of the cohort, with variations based on surgical procedure. After adjusting for risk, NIT was not significantly associated with major neurological injuries overall, but a lower NIT showed protective effects in the Norwood subgroup. Factors increasing the risk of major neurological injury included younger age at surgery, the Norwood procedure, longer cardiopulmonary bypass times, younger gestational age, presence of noncardiac abnormalities, and chromosomal anomalies. CONCLUSIONS: Whereas neurological injuries are prevalent after neonatal cardiac surgery, current practices lean towards higher core temperatures. This trend is supported by the nonsignificant impact of NIT on neurological outcomes. However, lower NIT in the Norwood subgroup indicates that reduced temperatures may be beneficial amidst specific risk factors.

Endocarditis and Incomplete Endothelialization 12 Years after Amplatzer Septal Occluder Deployment.

A 4-year-old boy had a 15-mm atrial septal defect repaired percutaneously with use of an Amplatzer Septal Occluder. At age 16 years, he presented with a week's history of fever, chills, dyspnea, fatigue, and malaise. Cultures grew methicillin-sensitive Staphylococcus aureus. A transesophageal echocardiogram showed a 1.25 × 1.5-cm pedunculated mass on the left aspect of the atrial septum just superior to the mitral valve, and a smaller vegetation on the right inferior medial aspect of the septum. At surgery, visual examination of both sides of the septum revealed granulation tissue, the pedunculated mass, the small vegetation, and exposed metal wires that suggested incomplete endothelialization of the occluder. We removed the occluder and patched the septal defect. The patient returned to full activity after 4 months and was asymptomatic 3 years postoperatively. Our report reinforces the need for further investigation into prosthetic device endothelialization, endocarditis prophylaxis, and recommended levels of physical activity in patients whose devices might be incompletely endothelialized. In addition to reporting our patient's case, we review the medical literature on this topic.

Technique and results for integration of the quest MPS all-blood cardioplegia delivery unit for modified ultrafiltration.

All blood cardioplegia delivery units offer the advantage of removing additional crystalloid volumes associated with multidose crystalloid or 4:1 blood cardioplegia. Further reductions in crystalloid and prime volumes can be achieved if the cardioplegia delivery unit can be integrated as the modified ultrafiltration (MUF) unit as well. This article reports our technique and results for integration of the Quest MPS all-blood cardioplegia delivery unit (Quest Medical, Allen, TX) for modified ultrafiltration. The charts of 50 consecutive patients were reviewed. Patient age ranged from 3 days to 5 years. There were nine neonates. Patient weight ranged from 1.7 to 20.4 kg. Standard prime volumes were 400 cc for patients weighing less than 12 kg, and 800 cc for patients weighing more than 12 kg. Cardiopulmonary bypass time ranged from 32 to 231 minutes. All patients were perfused with corporeal temperatures above 31 degrees C except Norwood cases. MUF time ranged from 5 to 15 minutes with an average of 10.2 minutes. Volume removed ranged from 100 to 600 cc with an average of 239 cc. There was one mortality (2%), which was unrelated to MUF. Additional prime volume was not required to initiate MUF through the MPS cardioplegia unit. The Quest MPS all-blood CPG unit can be safely and effectively integrated as a MUF unit without additional prime volumes. This approach allows for mild hypothermic cardiopulmonary bypass, multidose all-blood CPG, and MUF to be used with tremendous limitation of crystalloid usage.

Results with all blood retrograde microplegia as a myocardial protection strategy for complex neonatal arch reconstruction.

Neonatal arch reconstructions present a challenge for myocardial protection. We report our results for eight patients treated with intermittent cold all blood retrograde cardioplegia during arch reconstruction using continuous selective normothermic cerebral perfusion. Over a 10-month period eight consecutive neonates underwent complex arch reconstruction. Mean age was 8.4 days (range 2-23); weight 3.1 kg (range 2.7-3.8). Diagnosis was hypoplastic left heart syndrome (5), interrupted aortic arch/ventriculoseptal defect (2), and complex AP window (1). Mean cardiopulmonary bypass time was 149 minutes (range 80-201), mean cross-clamp time was 74 (range 51-101). All patients had primary chest closure and none required extra-corporeal membrane oxigenation. One patient (12%) had a period of low cardiac output syndrome, which resolved with high dose inotropes. All patients were discharged alive and well. Intermittent all blood retrograde microplegia is an effective myocardial protection strategy for complex neonatal arch reconstruction. Postoperative myocardial function is very good. This protection approach facilitates continuous selective normothermic cerebral perfusion.

Technique for the Norwood procedure using normothermic selective cerebral perfusion.

The Norwood procedure is commonly performed using either circulatory arrest or deep hypothermia with low-flow cardiopulmonary bypass. We describe our technique for the Norwood procedure using selective cerebral perfusion with corporeal normothermia (> 32 degrees C). A right radial artery catheter was placed and cerebral NIRS applied. A C-clamp was placed upon the innominate artery and gortex shunt placed. Cardiopulmonary bypass was established through the shunt. A 7.0 purse-string was placed at the beginning of the arch and a cross-clamp applied superior to this and cold cardioplegia was given by hand. The left carotid and subclavian were snared and a C-clamp was placed on the distal descending aorta. The cross-clamp was then repositioned across the base of the innominate and pump flow was reduced. This resulted in arch isolation with a bloodless field. Perfusion was then transferred to a neo-artic cannula and the central shunt completed. Cardiopulmonary bypass time was approximately 60 minutes and cardiac arrest time was approximately 20 minutes; core temperature had not dropped below 32 degrees C. The Norwood procedure can be successfully performed with normothermic selective cerebral perfusion thereby offering the theoretical benefit of avoiding deep hypothermia with or without circulatory arrest.