High-throughput and quantitative genome-wide messenger RNA sequencing for molecular phenotyping.

BACKGROUND: We present a genome-wide messenger RNA (mRNA) sequencing technique that converts small amounts of RNA from many samples into molecular phenotypes. It encompasses all steps from sample preparation to sequence analysis and is applicable to baseline profiling or perturbation measurements. RESULTS: Multiplex sequencing of transcript 3' ends identifies differential transcript abundance independent of gene annotation. We show that increasing biological replicate number while maintaining the total amount of sequencing identifies more differentially abundant transcripts. CONCLUSIONS: This method can be implemented on polyadenylated RNA from any organism with an annotated reference genome and in any laboratory with access to Illumina sequencing.

Cerebral near-infrared spectroscopy during cardiopulmonary bypass predicts superior vena cava oxygen saturation.

OBJECTIVE: Cerebral and flank near-infrared spectroscopy are used to monitor tissue oxygenation during cardiopulmonary bypass in pediatric patients. We sought to validate these noninvasive measurements as predictors of oxygen saturation in the superior and inferior venae cavae during cardiopulmonary bypass. METHODS: Eight patients underwent elective repair of congenital heart defects with bicaval cannulation. Ultrasonic flow probes and oximetric catheters were placed in the superior and inferior venae cavae limbs of the perfusion circuit. Cerebral and flank near-infrared spectroscopy and 12 additional variables were recorded each minute on cardiopulmonary bypass. Relationships between these variables and superior and inferior venae cavae oxygen saturation were analyzed by linear mixed modeling. The regression of superior vena cava oxygen saturation by current cerebral near-infrared spectroscopy and 1-minute lag cerebral near-infrared spectroscopy, which are equivalent to the regression of the superior vena cava saturation by the current cerebral near-infrared spectroscopy and the 1-minute change in cerebral near-infrared spectroscopy, were used to assess cerebral near-infrared spectroscopy as a trend monitor. RESULTS: The mean number of observation time points per patient was 86 (median 72, range 34-194) for 690 total observations. The root mean square percentage error was 6.39% for the prediction model of superior vena cava saturation by single-factor cerebral near-infrared spectroscopy. The root mean square percentage error was 10.8% for the prediction model of inferior vena cava saturation by single-factor flank near-infrared spectroscopy. CONCLUSIONS: Cerebral near-infrared spectroscopy accurately predicts superior vena cava oxygen saturation and changes in superior vena cava oxygen saturation on cardiopulmonary bypass. The relationship between flank near-infrared spectroscopy and inferior vena cava saturation is not as strong.

Heart transplantation techniques after hybrid single-ventricle palliation.

The Norwood procedure for hypoplastic left heart syndrome (HLHS) aims to provide an unobstructed systemic outflow tract, unrestrictive inter-atrial communication, controlled source of pulmonary blood flow, and reliable source of coronary blood flow. The hybrid palliative strategy of pulmonary artery banding and ductal stenting has emerged as an alternative treatment for neonates with HLHS. Neonates who have undergone a hybrid Norwood but are not candidates for the three-stage single-ventricle pathway may need heart transplantation. Patients who have undergone hybrid Norwood or those with visceral heterotaxy who have undergone ductal stenting and bilateral PA bands represent a technically challenging group of patients for heart transplantation, but it appears to be a favorable approach and we describe our experience with three patients who underwent heart transplant after a hybrid Norwood procedure.

Ministernotomy for repair of congenital cardiac disease.

We report our experience with repair of a variety of congenital heart defects utilizing a ministernotomy incision. A ministernotomy was used in 79 patients with a variety of congenital heart diseases from November 2004 to August 2007. Patients included 36 males and 43 females with ages ranging from 1 month to 122 months (median age, 22 months). The weight ranged from 3.5 kg to 40 kg (median weight, 10.9 kg). There were no deaths, and one conversion to full median sternotomy (1/79, 1.3%). The median cardiopulmonary bypass time was 59 min, and median aortic cross-clamp time was 38 min. One patient underwent atrial septal defect (ASD) repair with fibrillatory arrest time of 35 min. The operating time ranged from 103 min to 312 min (median operating time, 168 min). The intensive care unit (ICU) stay ranged from 1 to 21 days (median ICU stay, 1 day) and the hospital stay ranged from 2 to 56 days (median hospital stay, 4 days). There were no reinterventions for residual cardiac defects. We demonstrate the safety and efficacy of ministernotomy for the correction of a range of congenital heart defects with improved cosmetic results.

The aortic translocation (Nikaidoh) procedure: midterm results superior to the Rastelli procedure.

OBJECTIVE: Midterm follow-up is analyzed after the aortic translocation (Nikaidoh) procedure, an alternative to the Rastelli procedure for ventriculoarterial discordance, ventricular septal defect, and pulmonary stenosis. METHODS: Nineteen patients underwent a Nikaidoh procedure at a median age of 3.3 years (0.9-9.3 years). The native aortic valve was translocated from the right to the left ventricular outflow tract by full (n = 6) or partial (n = 13) mobilization of the aortic root. Seven patients with partial mobilization had the right coronary artery reimplanted as a button. The conal septum was divided in 13 patients. The right ventricular outflow tract was reconstructed with either a homograft (n = 4) or a right ventricular outflow tract patch (n = 15). The median follow-up was 11.4 years (0.1-23 years), and the median age at follow-up was 17.4 years (1-30 years). Left ventricular outflow tract obstruction and aortic insufficiency were assessed by echocardiography. RESULTS: One patient died of right coronary arterial ischemia. All remaining patients (95%) survived. The median survival was 13.6 years (longest, 23.0 years). Seven right ventricular outflow tract reoperations were required in 5 patients (6 with obstruction and 1 with pulmonary insufficiency). No reoperations have been performed on the left ventricular outflow tract or aortic valve. No patient had any left ventricular outflow tract obstruction or aortic insufficiency more than mild (mild in 9 patients, trivial in 3 patients, and absent in 6 patients). CONCLUSIONS: Midterm actuarial survival was 95% after the Nikaidoh procedure. Reintervention for the right ventricular outflow tract is more common when valved conduits are used versus valveless reconstruction; however, the Nikaidoh procedure provides complete freedom from important aortic insufficiency and left ventricular outflow tract obstruction.

The extracardiac lateral tunnel Fontan, constructed with bovine pericardium: comparison with the extracardiac conduit Fontan.

BACKGROUND: The Fontan procedure performed with an extracardiac conduit (ECC) has gained wide acceptance as an alternative to the intracardiac lateral tunnel because it avoids placement of extensive atrial suture lines and use of prosthetic material in the systemic circulation. The extracardiac lateral tunnel (ELT) is a modification of the Fontan procedure which uses pericardium and the external surface of the atrium to create a conduit from the inferior vena cava to the pulmonary artery. This surgery theoretically avoids disruption of intra-atrial conduction by eschewing endocardial suturing while maintaining conduit growth potential and the ability to easily create a fenestration to the systemic circulation. METHODS: We retrospectively analyzed the short-term outcome of 96 consecutive patients who underwent an extracardiac Fontan procedure. An ELT using bovine pericardium was performed in 59 patients, whereas 37 patients received a traditional ECC. RESULTS: The 2 groups were similar with respect to age (P = .96), body surface area (P = .54), number of preoperative Fontan risk factors (P = .43), and ventricular morphology (P = .72). There were no significant differences in the following outcome variables between the ELT and the traditional ECC: length of hospitalization (P = .73), duration of chest tube drainage (P = .48), abnormal rhythm at time of discharge (P = .27), and mortality (P = .63). CONCLUSIONS: The ELT Fontan can be performed with a low risk of mortality and complications. The results are equivalent to the traditional ECC procedure. The theoretical advantages of the procedure suggest that it should be considered a useful modification of Fontan surgery.

Fresh whole blood versus reconstituted blood for pump priming in heart surgery in infants.

BACKGROUND: In an attempt to reduce the coagulopathic and inflammatory responses seen after cardiopulmonary bypass, the use of fresh whole blood during heart operations has become the standard of care for neonates and infants at many institutions. We compared the use of fresh whole blood with the use of a combination of packed red cells and fresh-frozen plasma (reconstituted blood) for priming of the cardiopulmonary bypass circuit. METHODS: We conducted a single-center, randomized, double-blind, controlled trial involving children less than one year of age who underwent open-heart surgery. Patients were assigned to receive either fresh whole blood that had been collected not more than 48 hours previously (96 patients) or reconstituted blood (104 patients) for bypass-circuit priming. Clinical outcomes and serologic measures of systemic inflammation and myocardial injury were compared between the groups. RESULTS: The group that received reconstituted blood had a shorter stay in the intensive care unit than the group that received fresh whole blood (70.5 hours vs. 97.0 hours, P=0.04). The group that received reconstituted blood also had a smaller cumulative fluid balance at 48 hours (-6.9 ml per kilogram of body weight vs. 28.8 ml per kilogram, P=0.003). Early postoperative chest-tube output, blood-product transfusion requirements, and levels of serum mediators of inflammation and cardiac troponin I were similar in the two groups. CONCLUSIONS: The use of fresh whole blood for cardiopulmonary bypass priming has no advantage over the use of a combination of packed red cells and fresh-frozen plasma during surgery for congenital heart disease. Moreover, circuit priming with fresh whole blood is associated with an increased length of stay in the intensive care unit and increased perioperative fluid overload.

Fenestration improves clinical outcome of the fontan procedure: a prospective, randomized study.

BACKGROUND: The Fontan procedure is the definitive operation for palliation of complex congenital heart disease with single-ventricle physiology. Fenestration of the Fontan circuit allows for shunting of deoxygenated blood to the systemic circulation. This procedure improved the clinical outcomes of patients who are at high risk for poor Fontan results. However, it is controversial whether fenestration is beneficial for standard-risk patients. METHODS AND RESULTS: This prospective, randomized trial evaluated the clinical utility of fenestration in patients with standard preoperative risk profiles for Fontan surgery. Forty-nine consecutive patients were assigned to undergo either a fenestrated (25 patients) or nonfenestrated (24 patients) Fontan procedure. The fenestrated and nonfenestrated groups were comparable with respect to age (P=0.944), body surface area (P=0.250), number of preoperative risk factors for poor outcome (P=0.681), cardiopulmonary bypass time (P=0.302), number of patients who required aortic cross-clamping (P=0.240), preoperative oxygen saturation (P=0.101), and number of patients with dominant left ventricular morphology (P=0.534). Patients in the fenestrated group had 55% less total chest tube drainage (P=0.036), 41% shorter total hospitalization (P=0.018), and 67% fewer additional procedures in the postoperative period (P=0.006) than those in the nonfenestrated group. CONCLUSIONS: Baffle fenestration performed at the time of Fontan surgery improves short-term outcome in standard-risk patients by decreasing pleural drainage, hospital length of stay, and need for additional postoperative procedures.