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G Wernovsky

Publications and source records attributed to G Wernovsky.

At least 55 records · Page 3Linked to original sources
PubMed1997

Factors that influence the development of atrial flutter after the Fontan operation.

OBJECTIVES: Atrial flutter is a frequent, potentially fatal complication of the Fontan operation, but risk factors for its development are ill defined. We evaluated clinical features that might predict the development of atrial flutter in patients who had a Fontan operation. METHODS: We evaluated 334 early survivors of a Fontan operation done between April 1973 and July 1991 (mean follow-up, 5.0 +/- 3.8 years). Evaluation included electrocardiography, Holter monitor recordings, and chart review. Modifications of the Fontan operation included an extracardiac conduit (n = 43), an atriopulmonary anastomosis (n = 117), or a total cavopulmonary anastomosis (n = 174). Patient, time, and procedure-related variables were analyzed with respect to the development of atrial flutter. RESULTS: Atrial flutter was identified in 54 (16%) patients at a mean of 5.3 +/- 4.7 years (range 0 to 19.7 years) after Fontan operation. Atrial flutter developed sooner and was more likely to occur in patients who were older at the time of Fontan operation (12.4 +/- 7.6 vs 6.3 +/- 5.2 years; p < 0.001), had a longer follow-up interval (8.7 +/- 3.9 vs 4.4 +/- 3.4 years; p < 0.001), had a prior atrial septectomy or pulmonary artery reconstruction (p < 0.01), and had worse New York Heart Association class symptoms (p < 0.02). The presence of sinus node dysfunction was associated with a higher incidence of atrial flutter (p < 0.001). Although there was a lower prevalence of atrial flutter in those patients with a total cavopulmonary anastomosis, the follow-up for this group was shorter. Anatomic diagnoses, perioperative hemodynamics, and other previous palliative operations were not associated with an increased incidence of atrial flutter. Multivariate analysis identified age at operation, duration of follow-up, extensive atrial baffling, and type of repair as factors associated with the development of atrial flutter after Fontan operation. CONCLUSION: Atrial flutter continues to develop with time after the Fontan operation. Further follow-up is necessary to determine whether a total cavopulmonary anastomosis reduces the incidence of atrial flutter.

Atrial Flutter↗
PubMed1997

Patterns of developmental dysfunction after surgery during infancy to correct transposition of the great arteries.

A randomized clinical trial was conducted to compare the early development of children with d-transposition of the great arteries (N = 171) repaired by an arterial switch operation that used either predominantly total circulatory arrest or predominantly continuous low-flow cardiopulmonary bypass. The children assigned to the circulatory arrest group scored lower than those assigned to low-flow bypass on the Bayley Scales of Infant Development at 1 year of age. Responses to parental questionnaires completed when the children were 2.5 years old indicated that the children in the circulatory arrest group, especially those with a ventricular septal defect, also manifested poorer expressive language and were considered to display more internalizing and externalizing problem behaviors. The use of circulatory arrest to protect vital organs during open heart surgery might place children at increased risk of early developmental difficulties, especially in the domains of motor and language function.

Brain Damage, Chronic↗
PubMed1996

Staged operation to Fontan increases the incidence of sinoatrial node dysfunction.

Morbidity and mortality of total cavopulmonary connection (modified Fontan procedure) may be decreased in many patients with single ventricle in whom the risk of surgery is high by performing the operations in a staged fashion. Each operative intervention, however, exposes the sinoatrial node region to risk of injury, and a multistaged approach may increase the risk of altered sinoatrial node function in these patients. The purpose of this study was to compare the prevalence of perioperative arrhythmias in patients undergoing either a primary or staged approach to the Fontan operation. Records were retrospectively reviewed for all patients having a Fontan procedure between January 1988 and December 1992. Of 324 patients undergoing a Fontan operation, 227 had a Fontan operation without a prior cavopulmonary shunt (group 1) and 97 had a cavopulmonary shunt before a Fontan operation (group 2). Arrhythmias were classified as altered sinoatrial node function, supraventricular tachycardia, or atrioventricular block. The prevalence of both transient (resolving before hospital discharge) and fixed (persisting until hospital discharge) altered sinoatrial node function was similar for the two groups after cavopulmonary shunt or primary Fontan despite a heterogeneous patient population (group 1: 10.6%/4.4%; group 2: 10.3%/3.1%; p=0.28). Conversion from cavopulmonary shunt to Fontan in group 2 resulted in a higher prevalence of altered sinoatrial node function in the early postoperative period (transient: 23.7%; fixed: 23.7%; p < 0.001) and on follow-up (group 1: 7.7%; group 2: 16.7%; p < 0.02). In group 2, 40 of 82 patients without arrhythmia after first intervention (cavopulmonary shunt) had an arrhythmia after the second intervention (Fontan) (49%); of 14 with an arrhythmia after the first operation, 10 (71%) had one at the second intervention (p < 0.01). In conclusion, a multistaged operative pathway to Fontan reconstruction is associated with a higher early risk of altered sinoatrial node function. The occurrence of altered sinoatrial node function after cavopulmonary shunt is itself a risk factor for arrhythmia after the Fontan operation. Longer follow-up is needed to assess the full impact of this finding.

Adolescent↗
PubMed1996

Sepsis, septic shock, acute abdomen? The ability of cardiac disease to mimic other medical illness.

Transport medicine offers the challenge of patient diagnosis based only on the relayed history an the impressions of referring medical personnel. A thorough pretransport review of the patient's history, physical examination, radiographs, laboratory values, and other supporting information can help avoid surprises upon arrival at the patient's bedside and lead to an appropriate diagnosis and management plan. One must approach the transported child with an open mind, however, to avoid misdiagnosis and inadequate or inappropriate intervention and management. One of the advantages of pediatric specialty transport services is the ability to critically assess a referred patient and offer diagnostic and therapeutic guidance in addition to transportation to the receiving center. These above two examples illustrate difficult cases where the diagnostic skills of the transport medical personnel enabled the patients to receive appropriate acute interventional and specific disease-related therapy.

Abdomen, Acute↗
PubMed1995

Sternotomy approach for the modified Blalock-Taussig shunt.

BACKGROUND: Since 1990, sternotomy has been the preferred approach for construction of a modified Blalock-Taussig shunt (MBTS) at Children's Hospital, Boston, Mass. In retrospect, we sought to test the hypothesis that this approach yields less mortality and morbidity than the traditional thoracotomy approach. METHODS AND RESULTS: One hundred four primary MBTSs with polytetrafluoroethylene grafts were constructed in patients from January 1988 through December 1992. Fifty-two shunts were constructed by thoracotomy approach and 52 by sternotomy approach. Fifteen of the thoracotomy patients were less than one month of age (8 less than 7 days), while 36 of the sternotomy patients were less than 1 month of age (20 less than 7 days). There were 10 shunt failures and 3 hospital deaths in the thoracotomy group and 4 shunt failures with 6 hospital deaths in the sternotomy group. The overall hospital mortality rate for the group was 8.7% (9 of 104). The operative route was not a significant predictor of hospital mortality (P = .30). However, there was a significant difference between the two operative approaches in shunt failure, with shunts that were created by thoracotomy four times more likely to fail than those created by the sternotomy route (odds ratio, OR, 3.88; 95% CI, 1.01 to 15.03; P = .049). The side of the shunt was also a significant predictor of failure with left-side MBTSs foru times more prone to failure (OR, 4.02; 95% CI, 1.19 to 15.25; P = .025). CONCLUSIONS: The sternotomy route is technically less challenging and is associated with fewer shunt failures than the classic thoracotomy approach. The potential theoretical disadvantages of this method for future sternal reentry for subsequent procedures was not apparent but requires prospective analysis.

Adolescent↗
PubMed1995

Postoperative course and hemodynamic profile after the arterial switch operation in neonates and infants. A comparison of low-flow cardiopulmonary bypass and circulatory arrest.

BACKGROUND: The neurological morbidity associated with prolonged periods of circulatory arrest has led some cardiac surgical teams to promote continuous low-flow cardiopulmonary bypass as an alternative strategy. The nonneurological postoperative effects of both techniques have been previously studied only in a limited fashion. METHODS AND RESULTS: We compared the hemodynamic profile (cardiac index and systemic and pulmonary vascular resistances), intraoperative and postoperative fluid balance, and perioperative course after deep hypothermia and support consisting predominantly of total circulatory arrest or low-flow cardiopulmonary bypass in a randomized, single-center trial. Eligibility criteria included a diagnosis of transposition of the great arteries and a planned arterial switch operation before the age of 3 months. Of the 171 patients, 129 (66 assigned to circulatory arrest and 63 to low-flow bypass) had an intact ventricular septum and 42 (21 assigned to circulatory arrest and 21 to low-flow bypass) had an associated ventricular septal defect. There were 3 (1.8%) hospital deaths. Patients assigned to low-flow bypass had significantly greater weight gain and positive fluid balance compared with patients assigned to circulatory arrest. Despite the increased weight gain in the infants assigned to low-flow bypass, the duration of mechanical ventilation, stay in the intensive care unit, and hospital stay were similar in both groups. Hemodynamic measurements were made in 122 patients. During the first postoperative night, the cardiac index decreased (32.1 +/- 15.4%, mean +/- SD), while pulmonary and systemic vascular resistance increased. The measured cardiac index was < 2.0 L.min-1.m-2 in 23.8% of the patients, with the lowest measurement typically occurring 9 to 12 hours after surgery. Perfusion strategy assignment was not associated with postoperative hemodynamics or other nonneurological postoperative events. CONCLUSIONS: After heart surgery in neonates and infants, both low-flow bypass and circulatory arrest perfusion strategies have comparable effects on the nonneurological postoperative course and hemodynamic profile.

Cardiopulmonary Bypass↗
PubMed1995

Coronary artery abnormalities detected at cardiac catheterization following the arterial switch operation for transposition of the great arteries.

Because the arterial switch operation has become the routine surgical approach for transposition of the great arteries, there is increasing awareness of adverse sequelae in some survivors. For the arterial switch to be considered the procedure of choice for transposition of the great arteries, long-term patency and normal function of the translocated coronary arteries must be achieved. We reviewed the cineangiograms and hemodynamic data in 366 patients who underwent postoperative catheterization after arterial switch operation. Of these, 13 patients (3%) had previously unsuspected coronary abnormalities diagnosed angiographically. No patient had noninvasive evidence of resting systolic dysfunction. Findings included left main coronary artery stenosis (n = 3) or occlusion (n = 2), anterior descending coronary artery stenosis (n = 1) or occlusion (n = 2), right coronary artery stenosis (n = 1) or occlusion (n = 1), and small coronary artery fistulas (n = 3). One patient died suddenly 3.3 years after surgery, 1 patient is lost to follow-up, and the remaining 10 patients are alive and asymptomatic up to 11 years after surgery.

Cardiac Catheterization↗
PubMed1995

Video-assisted thoracoscopic vascular ring division in infants and children.

OBJECTIVES: This study evaluated our early experience with video-assisted thoracoscopic vascular ring division and compared this approach with division by means of a conventional open thoracotomy. BACKGROUND: Video-assisted thoracoscopic techniques reduce surgical trauma and have been applied to several adult thoracic procedures; however, pediatric applications have been limited. We developed instruments and techniques for video-assisted thoracoscopic vascular ring division in the pediatric population. METHODS: We compared patient characteristics, operative results and postoperative hospital courses of all patients undergoing vascular ring division by a video-assisted approach with a historical control group of all patients undergoing division by an open thoracotomy between January 1991 and December 1992. RESULTS: Eight patients (median age 5 months, range 40 days to 5.5 years; median weight 6.2 kg, range 1.8 to 17.1) underwent video-assisted thoracoscopic vascular ring division. Four had a double aortic arch with an atretic left arch and a left ligamentum, and four had a right aortic arch with aberrant left subclavian artery and a left ligamentum. All eight had successful ring division with symptomatic relief and no mortality. A limited thoracotomy was performed in three patients to divide patent vascular structures, and the hospital period was prolonged in one because of chylothorax. These eight patients were compared with a historical cohort of eight pediatric patients having vascular ring division performed by a conventional thoracotomy. The two groups did not differ in age, weight, intensive care unit or postoperative hospital stay, duration of intubation or thoracostomy tube or hospital charges. Total operating room time was longer for the group undergoing video-assisted operation. CONCLUSIONS: Early results for video-assisted thoracoscopic vascular ring division are comparable to those of the conventional surgical approach. With further refinement in technique and instrumentation, video-assisted surgical intervention may become a viable alternative to open thoracotomy for management of the symptomatic vascular ring.

Aorta, Thoracic↗
PubMed1995

Developmental and neurologic status of children after heart surgery with hypothermic circulatory arrest or low-flow cardiopulmonary bypass.

BACKGROUND: Deep hypothermia with either total circulatory arrest or low-flow cardiopulmonary bypass is used to support vital organs during heart surgery in infants. We compared the developmental and neurologic sequelae of these two strategies one year after surgery. METHODS: Infants with D-transposition of the great arteries who underwent an arterial-switch operation were randomly assigned to a method of support consisting predominantly of circulatory arrest or a method consisting predominantly of low-flow bypass. Developmental and neurologic evaluations and magnetic resonance imaging (MRI) were performed at one year of age. RESULTS: Of the 171 patients enrolled in the study, 155 were evaluated. After adjustment for the presence or absence of a ventricular septal defect, the infants assigned to circulatory arrest, as compared with those assigned to low-flow bypass, had a lower mean score on the Psychomotor Development Index of the Bayley Scales of Infant Development (a 6.5-point deficit, P = 0.01) and a higher proportion had scores < or = 80 (i.e., 2 SD or more below the population mean) (27 percent vs. 12 percent, P = 0.02). The score on the Psychomotor Development Index was inversely related to the duration of circulatory arrest (P = 0.02). The risk of neurologic abnormalities increased with the duration of circulatory arrest (P = 0.04). The method of support was not associated with the prevalence of abnormalities on MRI scans of the brain, scores on the Mental Development Index of the Bayley Scale, or scores on a test of visual-recognition memory. Perioperative electroencephalographic seizure activity was associated with lower scores on the Psychomotor Development Index (P = 0.002) and an increased likelihood of abnormalities on MRI scans of the brain (P < 0.001). CONCLUSIONS: Heart surgery performed with circulatory arrest as the predominant support strategy is associated with a higher risk of delayed motor development and neurologic abnormalities at the age of one year than is surgery with low-flow bypass as the predominant support strategy.

Brain↗
PubMed1995

Cerebrovascular accidents following the Fontan operation.

The Fontan operation is one of the most common cardiac operations for children with congenital heart disease beyond the first year of age. Although the surgical mortality of this procedure has improved over the past 2 decades, the neurologic outcome in this population is not well described. We performed a retrospective review of 645 patients who underwent the Fontan procedure at Children's Hospital in Boston over the 15-year period between August, 1978 and July, 1993, to describe the incidence of postoperative cerebrovascular accidents or strokes among survivors. We identified 17 patients (2.6%) who suffered a stroke following the Fontan operation. The risk period for stroke in our population extended from the first postoperative day to 32 months after the Fontan procedure. The pre-, intra-, and postoperative clinical features of these patients are described.

Adolescent↗
PubMed1995

Video-assisted thoracoscopic surgery for congenital heart disease.

Video-assisted endoscopic techniques have reduced operative trauma in adult thoracic and general surgery, but applications in children with congenital heart disease have been limited. We report the development of video-assisted thoracic surgery procedures for neonates and infants with cardiovascular disease. Endoscopic instruments and techniques for pediatric cardiovascular procedures were designed and tested in the animal laboratory. Forty-eight operations were subsequently performed in 46 pediatric patients ranging in age from 2 hours to 14 years (median 9 months), weighing from 575 grams to 54 kg (median 8.5 kg). Clinical applications included seven different surgical procedures: patent ductus arteriosus interruption in infants (n = 26) and premature neonates (n = 5), vascular ring division (n = 8), pericardial drainage and resection (n = 3), arterial and venous collateral interruption (n = 2), thoracic duct ligation (n = 2), epicardial pacemaker lead insertion (n = 1), and diagnostic thoracoscopy (n = 1). There was no operative mortality. Technical success, defined as a video-assisted procedure completed without incising chest wall muscle or spreading the ribs, was achieved in 39 of 48 procedures (82%), with thoracotomy required to complete nine procedures. Most patients (22/25, 88%) undergoing elective ductus ligation were extubated in the operating room and discharged from the hospital within 48 hours of the operation. Eight of the last 10 patients having ductus ligation were discharged on the first postoperative day. Residual ductal flow was assessed by (1) transesophageal echocardiography in the operating room (incidence: 0/25, 0%, 70% CL 0% to 7.3%); (2) discharge auscultation (incidence: 1/30, 3%, 70% CL 0.5% to 10.8%); and (3) follow-up Doppler echocardiography (incidence: 3/25, 12%, 70% CL 5.4% to 22.6%). Video-assisted thoracoscopic techniques can be safely applied to pediatric patients with patent ductus arteriosus and vascular rings and may become an effective addition to the staged management of more complex forms of congenital heart disease.

Adolescent↗
PubMed1995

Factors influencing early and late outcome of the arterial switch operation for transposition of the great arteries.

Between January 1983 and January 1992, 470 patients underwent an arterial switch operation at our institution. An intact (or virtually intact) ventricular septum was present in 278 of 470 (59%); a ventricular septal defect was closed in the remaining 192. Survivals at 1 month and 1, 5, and 8 years among the 470 patients were 93%, 92%, 91%, and 91%, respectively. The hazard function for death (at any time) had a rapidly declining single phase that approached zero by one year after the operation. Risk factors for death included coronary artery patterns with a retropulmonary course of the left coronary artery (two types) and a pattern in which the right coronary artery and left anterior descending arose from the anterior sinus with a posterior course of the circumflex coronary. The only procedural risk factor identified was augmentation of the aortic arch; longer duration of circulatory arrest was also a risk factor for death. Earlier date of operation was a risk factor for death, but only in the case of the senior surgeon. Reinterventions were performed to relieve right ventricular and/or pulmonary artery stenoses alone in 28 patients. The hazard function for reintervention for pulmonary artery or valve stenosis revealed an early phase that peaked at 9 months after the operation and a constant phase for the duration of follow-up. Incremental risk factors for the early phase included multiple ventricular septal defects, the rapid two-stage arterial switch, and a coronary pattern with a single ostium supplying the right coronary and left anterior descending, with a retropulmonary course of the circumflex. The need for reintervention has decreased with time. The arterial switch operation can currently be performed early in life with a low mortality risk (< 5%) and a low incidence of reintervention (< 10%) for supravalvular pulmonary stenosis. The analyses indicate that both the mortality and reintervention risks are lower in patients with less complex anatomy.

Child, Preschool↗
PubMed1995

Arrhythmias and intracardiac conduction after the arterial switch operation.

UNLABELLED: Intraatrial baffling procedures such as the Mustard or Senning repair of transposition of the great arteries have been associated with a high incidence of cardiac arrhythmias. These abnormalities are thought to arise from trauma to the sinus node and atrial muscle during the procedure. In the arterial switch operation, there is little intraatrial manipulation other than the repair of the atrial septal defect. In theory, rhythm disturbances after the arterial switch operation should be less prevalent. From January 1, 1983, to December 31, 1990, 390 patients (230 with intact ventricular septum and 160 with a coexisting ventricular septal defect) underwent an arterial switch operation. Electrocardiograms and 24-hour Holter monitor studies were obtained in the 364 survivors at hospital discharge and during follow-up. Limited intracardiac electrophysiologic studies were performed 6 to 12 months after the operation. RESULTS: Atrioventricular node function was preserved in most patients; seven patients (2%) had first-degree, two (0.7%) second-degree, and five (1.7%) had complete atrioventricular block (all with coexisting ventricular septal defect). All five patients with complete heart block received a permanent pacemaker. In those patients not having a permanent pacemaker, sinus rhythm was present in 96% on the surface electrocardiogram and 99% during 24-hour Holter monitor studies (1 month to 8.5 years, mean 2.1 years after the operation). Intracardiac electrophysiologic studies (n = 158) demonstrated normal corrected sinus node recovery times and AH intervals in 97% of patients. Atrial ectopy was present in 152 of 172 (81%) patients, with the majority (64%) of patients having only occasional premature beats without repetitive forms. Ventricular ectopy was a frequent finding during 24-hour monitoring. At hospital discharge 70% had ventricular ectopy; these values fell to 57% (in patients with intact ventricular septum) and 30% (in patients with a coexisting ventricular septal defect) at follow-up. In the early postoperative period, there were 25 episodes of supraventricular tachycardia (14 of which required therapy), 6 episodes of junctional ectopic tachycardia, and 9 episodes of ventricular tachycardia. The incidence of supraventricular tachycardia had fallen to 5% at follow-up, with no atrial flutter or fibrillation noted. Three patients had ventricular tachycardia on follow-up Holter studies. In summary, our results confirm the theoretical advantages of anatomic correction over atrial level correction of transposition of the great arteries with respect to preservation of sinus node function and low incidence of clinically significant tachyarrhythmias.

Arrhythmias, Cardiac↗
PubMed1995

Status of the left ventricle after arterial switch operation for transposition of the great arteries. Hemodynamic and echocardiographic evaluation.

BACKGROUND: The potential for improved preservation of systemic ventricular function represents an important reason for the increasing popularity of the arterial switch operation. In support of this expectation, prior studies in patients early after arterial switch operation have found normal ventricular contractility and function. This study was conducted to extend those observations to up to 10 years of follow-up and to directly examine the effects of a coexisting ventricular septal defect or short-term preparatory banding of the pulmonary artery before the arterial switch operation. METHODS: Patients operated on from 1983 through 1991 were included. Echocardiographic and catheterization data were collected as part of a prospective evaluation of outcome in all patients who undergo the arterial switch operation at Boston Children's Hospital, with inclusion of data from the most recent catheterization only. Echocardiograms performed at least 6 months after the operation were included, with assessment of both the most recent status as well as serial trends. Whenever possible, echocardiographic evaluation included data necessary to perform analysis of ventricular mechanics including indices of afterload, preload, and contractility. Comparison was made to normal values and between subgroups defined on the basis of an arterial switch operation with or without ventricular septal defect and those who had a rapid two-stage arterial switch operation. RESULTS: Invasive measures of left and right ventricular filling pressures, cardiac index, and pulmonary vascular resistance did not differ among the three groups. Overall, echocardiographic left ventricular end-diastolic dimension, wall thickness, mass, afterload (end-systolic wall stress), function (fractional shortening and rate-corrected velocity of fiber shortening), contractility (stress-velocity and stress-shortening relations), and preload were normal, and none of these variables was different between the groups with and without a ventricular septal defect. Serial evaluation indicated a slight but significant trend toward ventricular dilatation, perhaps related to a relatively high incidence of at least mild aortic regurgitation (30%). In contrast, in the rapid two-stage group the echocardiographic indices of left ventricular function (fractional shortening and velocity of fiber shortening) and contractility (stress-velocity and stress-shortening relations) were found to be mildly but significantly reduced compared with normal subjects and with the other arterial switch operation groups. Over the duration of follow-up encompassed by this study, no tendency toward progressive depression of function was seen. CONCLUSIONS: As the length of observation after the arterial switch operation continues to increase, left ventricular size, mass, functional status, and contractility continues to be normal, with no evidence of time-related deterioration of function. As previously reported, the rapid two-stage arterial switch operation does represent a higher risk for mild impairment of myocardial mechanics.

Aortic Valve Insufficiency↗
PubMed1995

Milrinone: systemic and pulmonary hemodynamic effects in neonates after cardiac surgery.

OBJECTIVE: To evaluate the hemodynamic effects of intravenous milrinone in neonates with low cardiac output after cardiac surgery. DESIGN: Prospective cohort study. SETTING: Pediatric cardiac intensive care unit. PATIENTS: Ten neonates with low cardiac output (cardiac index of < or = 3.0 L/min/m2) after corrective cardiac surgery were enrolled in the study. The neonates' ages ranged from 3 to 27 days (median 5) and their weights ranged from 2.0 to 4.8 kg (median 3.7). The diagnoses were: transposition of the great arteries (n = 6, including two with ventricular septal defect), tetralogy of Fallot (n = 2), truncus arteriosus (n = 1), and total anomalous pulmonary venous connection (n = 1). INTERVENTIONS: Milrinone was intravenously administered in three stages: a) baseline stage, in which patients had a stable hemodynamic status, ventilation and gas exchange, hemostasis, and body temperature; b) loading stage, in which a 50 microgram/kg intravenous loading dose of milrinone was administered over 15 mins; and c) infusion stage, in which milrinone was continuously infused at 0.50 microgram/kg/min for 30 mins. MEASUREMENTS AND MAIN RESULTS: The mean heart rate increased after the loading stage (149 +/- 13 to 163 +/- 12 beats/min, p < .01) but slowed during the infusion stage (154 +/- 11 beats/min, p < .01 vs. loading stage). Both right and left atrial pressures were lowered in all ten neonates. Compared with baseline, mean arterial pressure decreased after the loading stage (66 +/- 12 to 57 +/- 10 mm Hg, p < .01) but did not decrease further at the infusion stage (59 +/- 12 mm Hg); changes in mean pulmonary arterial pressure were comparable. Cardiac index increased from a baseline mean of 2.1 +/- 0.5 to 3.0 +/- 0.8 L/min/m2 (p < .01) with the loading stage, and was maintained at 3.1 +/- 0.6 L/min/m2 during the infusion stage. Systemic vascular resistance index decreased below baseline values with loading, from 2136 +/- 432 to 1336 +/- 400 dyne.sec/cm5.m2 (p < .01), and pulmonary vascular resistance index also decreased with loading dose of milrinone, from 488 +/- 160 to 360 +/- 120 dyne.sec/cm5.m2 (p < .01). There was no change in the rate pressure index, an indirect measurement of myocardial oxygen consumption, throughout the study. CONCLUSIONS: Administration of milrinone in neonates with low cardiac output after cardiac surgery lowers filling pressures, systemic and pulmonary arterial pressures, and systemic and pulmonary vascular resistances, while improving cardiac index. Milrinone increases heart rate without altering myocardial oxygen consumption. While milrinone appears to be effective and safe during short-term use, the relative distribution of inotropic and vasodilatory properties of milrinone remains to be elucidated.

Cardiac Output, Low↗
PubMed1994

Video-assisted cardioscopy in congenital heart operations.

Recent advances in fiberoptics and endoscopic imaging technology have extended the applications of video assistance in surgical procedures. Video-assisted thoracoscopic surgical techniques have been employed to improve anatomic visualization within the pleural space and to reduce chest wall trauma. Open heart operations for congenital heart disease in neonates and infants also require clear visualization of small structures within confined spaces. By adapting pediatric thoracoscopic instrumentation, we have developed a technique for video-assisted cardioscopy. This technique was used in 4 patients with complex congenital heart disease to expose remote intracardiac structures and facilitate surgical repair. The patients ranged in weight from 4.6 to 17 kilograms, and visualization of the intended structures was achieved in each case within 12 minutes. There were no complications associated with the videoscope. Further experience with video-assisted cardioscopy might broaden its role as an adjunct to the surgical repair of complex congenital heart defects.

Cardiac Surgical Procedures↗