Wanda C. Miller-Hance

Intraoperative transesophageal echocardiography for pediatric patients with congenital heart disease.

I ntraoperative transesophageal echocardiography (TEE) has been used in adult cardiac patients since the mid-1980s for the evaluation of valvular repair (1,2) and prosthetic valve function (3,4), and for monitoring of myocardial ischemia (5,6) and left ventricular preload (7-9). I mmediate detection of inadequate surgical repairs by TEE improves surgical corrections, thereby avoiding subsequent reoperations and reducing morbidity, mortality, and cost (10). Until 1990, intraoperative evaluation of infants and children undergoing congenital heart surgery was not feasible with TEE because probe sizes were too large for most children. The subsequent development of miniaturized probes has generated a number of studies, which have demonstrated that TEE can be performed safely in the pediatric population and provide substantial benefit as well (11-15). This review focuses on the evolution of intraoperative echocardiography for the evaluation of congenital heart surgery and the current practice of pediatric TEE in the operating room (OR). Our goal is to provide a reference source to those involved in the perioperative management of infants and children with congenital heart disease.

Myocardial Performance Index with Sevoflurane–Pancuronium versus Fentanyl–Midazolam–Pancuronium in Infants with a Functional Single Ventricle

Background:Patients with congenital heart disease characterized by a functional single ventricle make up an increasing number of patients presenting for cardiac or noncardiac surgery. Conventional echocardiographic methods to measure left ventricular function, i.e., ejection fraction, are invalid in these patients because of altered ventricular geometry. Two recently described Doppler echocardiographic modalities, the myocardial performance index and Doppler tissue imaging, can be applied to single-ventricle patients because they are independent of ventricular geometry. This study assessed the changes in myocardial performance index and Doppler tissue imaging in response to two anesthetic regimens, fentanyl–midazolam–pancuronium and sevoflurane–pancuronium. Methods:Thirty patients aged 4–12 months with a functional single ventricle were randomized to receive fentanyl–midazolam or sevoflurane. Myocardial performance index and Doppler tissue imaging were measured by transthoracic echocardiography at baseline and two clinically relevant dose levels. Results:Sixteen patients receiving sevoflurane and 14 receiving fentanyl–midazolam were studied. Myocardial performance index was unchanged from baseline with either agent (fentanyl–midazolam: 0.50 ± 15 baseline vs. 0.51 ± 0.15 at dose 2; sevoflurane: 0.42 ± 0.14 baseline vs. 0.46 ± 0.09 at dose 2). Doppler tissue imaging S (systolic)– and E (early diastolic)–wave velocities in the lateral ventricular walls at the level of the atrioventricular valve annulus were unchanged in the sevoflurane group; however, both Doppler tissue imaging S- and E-wave velocities were decreased significantly from baseline at dose 1 and dose 2 with fentanyl–midazolam, consistent with decreased longitudinal systolic and diastolic ventricular function. Conclusions:Myocardial performance index, a global measurement of combined systolic and diastolic ventricular function, is not affected by commonly used doses of fentanyl–midazolam or sevoflurane in infants with a functional single ventricle.

Congenital heart disease in the adult: a review with internet-accessible transesophageal echocardiographic images.

T he number of adults recognized with congenital heart disease (CHD) has increased dramatically over the past five decades because of significant advances in diagnosis and medical and surgical care. At the moment, the population of adults with CHD (ACHD) in the United States is estimated at approximately one million (1). For the first time, the number of adults with congenital cardiovascular malformations equals the number of children with these disorders. With additional refinements in surgical techniques and definitive repair at an earlier age, this patient group is likely to increase even further. Survival rates in CHD are influenced by many factors, including year of birth, age at diagnosis, complexity of the pathology, and whether the lesion(s) has been palliated or surgically corrected (Table 1) (1). As survival and life expectancy continue to improve, a growing number of unoperated, palliated, and “repaired” individuals require surgical interventions or other procedures related or unrelated to their heart disease. The care of these patients is becoming more frequent in all surgical settings, including tertiary care facilities, ambulatory centers, and labor and delivery suites. Adults with CHD may come to the attention of anesthesiologists for various indications including:

Left ventricular noncompaction cardiomyopathy in association with trisomy 13.

In recent years, left ventricular noncompaction (LVNC) has been recognized as a distinct form of cardiomyopathy with its own clinical presentation and natural history. More than 100 cases of LVNC have been described in children. Although LVNC has been described in association with metabolic disorders such as Fabrys disease or genetic disorders such as Roifmans syndrome, this case represents the first report of LVNC in a child with trisomy 13.

Role of transesophageal echocardiography in the management of pediatric patients with congenital heart disease.

Transesophageal echocardiography (TEE) has become a critical diagnostic and perioperative management tool for patients with congenital heart disease (CHD) undergoing cardiac and noncardiac surgical procedures. This review highlights the role of TEE in routine management of pediatric cardiac patient population with focus on indications, views, applications and technological advances.

Management of postoperative chylopericardium in childhood.

1. Josephson ME, Kastor JA. Paroxysmal supraventricular tachycardia. Is the atrium a necessary link? Circulation 1976;54:430-435. 2. Miller JM, Rosenthal ME, Vasallo JA, Josephson ME. Atrioventricular nodal reentrant tachycardia: studies on upper and lower “common pathways”. Circulation 1987:75:930-940. 3. Ross DL, Johhson DC, Denniss AR, Cooper MJ, Richards DA, Uther JB. Curative surgery for atrioventricular junctional (“AV nodal”) reentrant tachycardia. JACC 1985,6:1383S1392. 4. Cox JL, Holman WL, Cain ME. Cryosurgical treatment of atrioventricular node reentrant tachy-

Transesophageal echocardiography in tetralogy of Fallot.

Transesophageal echocardiography (TEE) plays an important role in the anatomical, functional, and hemodynamic assessment of patients with congenital heart disease (CHD). This imaging approach has been applied to both children and adults with a wide range of cardiovascular malformations. Extensive clinical experience documents significant contributions, particularly in the perioperative setting. In fact, in the current medical era, many consider this technology to be an essential adjunct to surgical and anesthetic management in CHD. This review focuses on the applications of TEE in patients with tetralogy of Fallot (TOF), the most common form of cyanotic heart disease. Emphasis is given to the perioperative use of this imaging modality and benefits derived during the prebypass and postbypass periods. Limitations and pitfalls relevant to the TEE assessment in patients with this anomaly are also addressed.

Continuous cerebral hemodynamic measurement during deep hypothermic circulatory arrest

While survival of children with complex congenital heart defects has improved in recent years, roughly half suffer neurological deficits suspected to be related to cerebral ischemia. Here we report the first demonstration of optical diffuse correlation spectroscopy (DCS) for continuous and non-invasive monitoring of cerebral microvascular blood flow during complex human neonatal or cardiac surgery. Comparison between DCS and Doppler ultrasound flow measurements during deep hypothermia, circulatory arrest, and rewarming were in good agreement. Looking forward, DCS instrumentation, alone and with NIRS, could provide access to flow and metabolic biomarkers needed by clinicians to adjust neuroprotective therapy during surgery.

Reliability of Intraoperative Contrast Transesophageal Echocardography for Detecting Interatrial Communications in Patients With Other Congenital Cardiovascular Malformations

The reliability of contrast transesophageal echocardiography (TEE) for diagnosing atrial communication has not been studied previously in patients with congenital heart disease. We prospectively evaluated the validity of intraoperative contrast TEE for determining atrial septal patency in a group of patients with congenital heart disease who underwent surgery using direct inspection for defi nitive diagnosis. Our study was prompted by the potential for surgical complications from paradoxic systemic air embolism 1 and observed cases of interatrial communications that were undetected despite a thorough preoperative assessment and intraoperative TEE including contrast studies. One child had severe neurologic damage due to systemic air embolization during open right-sided cardiac surgery with a beating heart.

Segmental wall-motion abnormalities after an arterial switch operation indicate ischemia.

We prospectively studied 29 consecutive neonates undergoing an arterial switch operation to determine if segmental wall motion abnormalities (SWMA) represented myocardial ischemia. Intraoperative transesophageal echocardiogram was recorded at baseline and twice after cardiopulmonary bypass. Cardiac troponin I (cTnI) levels were measured before sternal incision and 3, 6, 12, 24, 48, and 72 h after removal of the aortic cross-clamp. Immediate postoperative Holter and 15-lead electrocardiograms (ECG) were evaluated for ischemia. Transthoracic echocardiograms were obtained before hospital discharge. At bypass termination, immediately after protamine administration, segmental wall motion was normal in nine neonates and abnormal in 20. SWMA were transient in five and present at the time of chest closure in 15 neonates. Neonates in whom SWMA were present at chest closure had more segments involved than those in whom SWMA were transient (P > 0.001). Neonates with SWMA at chest closure had higher cTnI levels postoperatively versus neonates with normal wall motion (P = 0.02). Postoperative ECG data were available in 26 neonates. There was ECG evidence of myocardial ischemia in two of eight neonates with normal wall motion, one of five with transient SWMA, and nine of 13 with SWMA at chest closure. CTnI levels at 12, 24, and 48 h and intraoperative SWMA were predictive of postoperative SWMA. We believe these data indicate that SWMA, which persist at the completion of an arterial switch operation, and which are present in multiple myocardial segments, correlate with myocardial ischemia. Further follow-up of these patients is needed to determine if increased intraoperative myocardial ischemia correlates with long-term outcomes.