Search

We present the case of a neonate who was successfully treated with emergency hybrid palliation soon after birth, including a stent insertion into a severely thickened atrial septum and bilateral pulmonary artery banding. The patient was prenatally diagnosed with severe pulmonary venous hypertension owing to mitral atresia and intact atrial septum associated with functional single ventricle and coarctation of the aorta.

AIMS: The aims of this study were to provide a detailed descriptive analysis of pre-intervention morphologic and functional echocardiographic parameters in a large, unselected, multicentre cohort of neonates diagnosed with critical left heart obstruction and to compare echocardiographic features between the different subtypes of left-sided lesions. METHODS AND RESULTS: Pre-intervention echocardiograms for 651 patients from 19 Congenital Heart Surgeons' Society (CHSS) institutions were reviewed in a core lab according to a standardized protocol including >150 morphologic and functional variables. The four most common subtypes of lesions were: aortic atresia (AA)/mitral atresia (MA) (29% of patients), AA/mitral stenosis (MS) (20%), aortic stenosis (AS)/MS (26%), and isolated AS (iAS) (18%). Only 17% of patients with AS/MS had an apex-forming left ventricle, compared with 0% of those with AA/MA and AA/MS (P

Background Current laboratory tests measuring factor and factor inhibitor levels are limited in their ability to fully evaluate the hemostasis status of hemophilia patients. There are global assays including thromboelastogragh (TEG), Innovance ETP, and thrombinoscope measuring thrombin generation potential, which have potentials to provide more objective and clinically relevant markers to guide clinical management. However, performance characteristics of these global assays are not well-studied, and no parallel comparisons of three global assays have been made. Material and Methods With plasmas of 20 healthy individuals the normal variation of thrombin generation potential was determined for all three global assays. With five commercially available and three clinical plasma samples with different levels of factor VIII inhibitors, serial dilutions were made, and thrombin generation potentials were measured with the global assays. Results The means and standard deviations for thrombin generation potential of healthy individuals are 761.27±70.30 mm/min, 2126.43±441.62 nM/min, and 411.04±48.87 mA, by TEG, throminoscope and Innovance ETP respectively. Thrombinoscope shows a dose-dependent response to different levels of factor VIII inhibitors from the same patients, while Innovance ETP shows virtually no response to factor 8 inhibitors regardless of inhibitor levels. TEG appears more sensitive to factor VIII inhibitors than thrombinoscope, as a moderate level of factor VIII often abolishes thrombin generation by TEG (see Figure 1 for an example). Importantly, it was shown that the same levels of factor VIII inhibitor from different patients result in different level of inhibition for thrombin generation potential by thrombinoscope (Figure 2), which potentially explains the phenotypic heterogeneity of patients with same levels of factor VIII inhibition. Conclusion Global assays like thrombinoscope, but not Innovance ETP, offer an objective measurement of hemostasis in hemophilia patients with factor VIII inhibitors, which may lead to individualized hemophilia patient management. Future studies are warranted to validate the global assays clinically. Disclosures No relevant conflicts of interest to declare.

Mitral atresia is commonly seen as a part of the spectrum of hypoplastic left heart syndrome, and it is usually associated with multiple levels of systemic outflow tract obstruction. Isolated mitral atresia with a normal aortic valve is extremely rare. We report the rare combination of mitral atresia, transposition of the great arteries, and unobstructed systemic and pulmonary blood flow.

The atrioventricular (AV) conduction system in AV discordance remains unclear, especially in cases with complex cardiac anomaly. We report a case of accessory pathway reciprocating tachycardia in atrioventricular discordance (AVD) and mitral atresia with twin AV nodes. In this case, the anterior AV node was located along the atretic mitral valve. The anterior AV node was involved in tachycardia and the posterior AV node acted as a bystander during tachycardia. The anterior AV node in AVD can be located along the atretic mitral valve, and one of twin AV nodes might act as a bystander during AV reciprocating tachycardia.

Objective Intraoperative monitoring of the motor-evoked potential has been widely used in patients undergoing neurosurgery. Direct stimulation of the brain with high-frequency monopolar stimulation (HFMS) is one of the most common methods to produce motor-evoked potential. We studied the influence of HFMS on the rat cerebral cortex. Methods We applied 1.5, 15, 30, 40, or 50 mA of HFMS to the rat sensorimotor cortex by a short sequence of five monopolar, monophasic, anodal rectangular 500-Hz pulses. We delivered one short five-pulse train 100 times every 5 seconds and examined pre- and post-stimulation electroencephalograms and histological changes at the stimulation site. Results We observed no spike waves after HFMS in any of the rats. There was no change in the power spectrum or frequency content in any of the rats exposed to HFMS. Histologically, there was significant swelling of the dendrites in rats sacrificed immediately after exposure to 40- and 50-mA stimulation; the 50-mA stimulation group also exhibited slight swelling of the mitochondria. These findings were not obtained in any of the rats sacrificed 30 days after stimulation. Conclusion In rats exposed to a stimulation intensity of 30-mA or less, no morphological or electrophysiological changes were observed. However, the possibility that HFMS may affect neural tissue cannot be ruled out.

Background: Kilohertz frequency spinal cord stimulation (KHFSCS) is an emerging therapy for treating refractory neuropathic pain. Although KHFSCS has the potential to improve the lives of patients experiencing debilitating pain, its mechanisms of action are unknown and thus it is difficult to optimize its development. Therefore, the goal of this study was to use a computer model to investigate the direct effects of KHFSCS on specific neural elements of the spinal cord. Methods: This computer model consisted of two main components: (1) finite element models of the electric field generated by KHFSCS and (2) multicompartment cable models of axons in the spinal cord. Model analysis permitted systematic investigation into a number of variables (e.g., dorsal cerebrospinal fluid thickness, lead location, fiber collateralization, and fiber size) and their corresponding effects on excitation and conduction block thresholds during KHFSCS. Results: The results of this study suggest that direct excitation of large-diameter dorsal column or dorsal root fibers require high stimulation amplitudes that are at the upper end or outside of the range used in clinical KHFSCS (i.e., 0.5 to 5 mA). Conduction block was only possible within the clinical range for a thin dorsal cerebrospinal fluid layer. Conclusions: These results suggest that clinical KHFSCS may not function through direct activation or conduction block of dorsal column or dorsal root fibers. Although these results should be validated with further studies, the authors propose that additional concepts and/or alternative hypotheses should be considered when examining the pain relief mechanisms of KHFSCS.

Hypoplastic left ventricle, also termed hypoplastic left heart syndrome, is often associated with a variety of deformities, such as AV and aortic arch anomalies. The specimens presented in this chapter are limited to show mitral atresia and mild hypoplastic LV.

The concept of univentricular heart moved from hearts with only one ventricle connected with atria [double inlet ventricle or absent atrioventricular (AV) connection] to hearts not amenable to biventricular repair, namely hearts with two ventricles unable to sustain separately pulmonary and systemic circulations in sequence. In the latter definition, even hearts with one hypoplastic ventricle are considered “functional” univentricular hearts. They include pulmonary/aortic atresia or severe stenosis with hypoplastic ventricle, and rare conditions like huge intramural cardiac tumors and Ebstein anomaly with extreme atrialization of right ventricular cavity. In this setting, the surgical repair is univentricular with “Fontan” operation, bypassing the ventricular mass. In other words, functionally univentricular heart is a condition in which, after surgery, only one ventricle sustain systemic circulation. Univentricular hearts (double inlet or absent AV connection) almost invariably show two ventricular chambers, one main and one accessory, which lacks an inlet portion. The latter is located posteriorly when morphologically left and anteriorly when morphologically right. As far as double inlet left ventricle, this is usually associated with discordant ventriculo-arterial (VA) connection (transposition of the great arteries) and all the blood flow to the aorta, which takes origin from the hypoplastic anterior right ventricle, is ventricular septal defect (bulbo-ventricular foramen) dependent. If restrictive, an aortic arch obstruction may be present. Double inlet left ventricle may be rarely associated with VA concordance (Holmes heart). As far as double inlet right ventricle with posterior hypoplastic left ventricular cavity, ventriculo-arterial connection is usually of double outlet type; thus the term double inlet–outlet right ventricle may be coined. Absent right or left AV connection may develop in the setting of both d- or l-loop, whatever the situs. In this condition, the contra-lateral patent AV valve may be either mitral or tricuspid in terms of morphology and the underlying ventricle (main chamber) either morphologically left or right. Establishing the loop, whatever right or left (also called right or left ventricular topology), is a fundamental step in the segmental-sequential analysis of congenital heart disease.

To assess the similarity of the behavioural effects of the rapid transcranial magnetic stimulation (rTMS) to those produced by other antidepressant treatments, in particular to repeated electroconvulsive shock (ECS), we carried out experiments on Wistar rats. The effects of a standard ECS procedure (9 daily treatments; the current parameters: 150 mA, 50 Hz, 0.5 s) were compared with 18 d treatment with rTMS of the same field intensity of 1.6 T but with different stimulation frequency (20 or 30 Hz) and a different number of sessions (9 or 18). Twenty-four hours after the last treatment the forced swimming test was carried out and the immobility time was recorded. The standard ECT reduced the immobility by 50%, the intensive rTMS (90 or 104 K impulses for the whole period of treatment) caused a significant effect, although smaller than that induced by ECT (reduction by 20-30%). The stimulation at 20 Hz required 18 treatment sessions to produce a significant effect, while only 9 sessions with stimulation at 30 Hz were sufficient to produce a comparable result. This suggests that the effectiveness of rTMS may be augmented by increasing the number or frequency of rTMS impulses.

The surgical strategy in infants with mitral valve stenosis or atresia without diminutive ascending aorta remains to be established, including the potential for biventricular repair as a definitive operation. Our surgical experience of six infants with mitral valve stenosis (4patients) or atresia (2patients) without diminutive ascending aorta was evaluated based on three important factors:left ventricular volume;the nature of the systemic outflow obstruction; and the type of mitral valve anomaly. Two patients with systemic outflow tract diameter less than 65% of normal underwent systemic outflow tract reconstruction, and the other patients with outflow tract diameter more than 68%of normal were able to maintain systemic circulation without repair. Only one patient with mitral valve stenosis without left ventricular outflow tract obstruction underwent a successful open mitral valvotomy as a biventricular repair after first-stage palliation. The left ventricle of the other patients did not grow after first-stage palliation. Due to progressive subaortic narrowing, pulmonary artery banding should be avoided in patients with mitral atresia due to absent atrioventricular connection who are future Fontan candidates. Most patients with this lesion can be expected to become candidates for safe Fontan-type repair.

Despite improvements in survival of patients with hypoplastic left heart syndrome (HLHS) with various palliative procedures, certain risk factors, such as weight less than 2.5 kg, continue to predict increased mortality. We report the palliation of a patient with HLHS weighing 1.4 kg via a hybrid procedure consisting of banding of the pulmonary arteries bilaterally, stenting the ductus arteriosus, and balloon atrial septostomy. We propose that this may be another alternative for palliation in this high-risk patient group.

[Figure][1] [![Graphic][3] ][3][![Graphic][4] ][4] A newborn was diagnosed as having hypoplastic left heart syndrome with mitral atresia. On echocardiography, 4 pulmonary veins were seen connecting to the left atrium (LA). Color flow Doppler also showed a vessel that originated

Mitral atresia is a rare congenital heart defect when compared to atresia of other valves and it is often associated with other cardiac malformation such as patent ductus arteriosus, coarctation of the aorta, transposition of the great arteries, pulmonary stenosis, shunt defects, cor triatriatum, chamber, and valvular anomalies. There have been few reports of mitral atresia, therefore, the case of a 5-month-old male child with complaint of difficulty with breathing and echocardiographic diagnosis of atretic mitral valves, atrial septal defect of 15 mms, ventricular septal defect (VSD) of 10 mms and hypoplastic left ventricle is reported.

In this Chapter only congenital malformations of the mitral valve are considered, excluding atrioventricular septal defects, which are separately treated (see chapter “Atrioventricular septal defects”), as well as mitral atresia (see chapter “Hypoplastic left heart syndrome”).

A new stimulation pattern for evaluation of intense neuromuscular block (post-tetanic burst (PTB)) was compared with post-tetanic twitch (PTT) during spontaneous recovery from vecuronium-induced neuromuscular block. Thirty adult patients were allocated to two equal groups and we measured times from administration of vecuronium 0.1 mg kg −1 to return of PTB and PTT responses, and evoked responses to PTB and PTT stimuli. For PTB stimulation, a 50-Hz tetanus was applied at 50 mA for 5 s, and after a pause of 3 s, a 50-Hz burst stimulation was applied, consisting of three impulses at 50 mA. PTB stimuli were delivered every 5 min. Similarly, PTT consisted of a tetanus, a 3-s pause and one single twitch stimulation repeated every 5 min. Time to return of the PTB response was significantly shorter than that of PTT (mean 23.7 (SD 7.9) compared with 30.7 (7.0) min) ( P = 0.0160), although evoked responses to PTB did not differ significantly from those of PTT throughout recovery from vecuronium-induced neuromuscular block. This study suggested that PTB was more sensitive in evaluating intense neuromuscular block than PTT. ( Br. J. Anaesth . 1995; 74 : 293–295)

Dr Gaynor: So what shunt, what operation would you do for that patient? Dr Photiadis: Right now I think there is no data. Our data do not show it, and there are no other data, so we would still use the B-T shunt. Dr. S. Sano (Okayama, Japan): Yes, a Sano would be probably a reasonable alternative. Dr Gaynor: That is the one finding that did come out in your studies. Dr E. Bove (Ann Arbor, MI, USA): I enjoyed your paper, and I agree with your conclusion, but I rise to support what Dr. Gaynor said, and I think that we have to be very careful how we interpret data. It is a retrospective study, and if I understood from your abstract, it was surgeon preference which was not very clear. Does that mean one surgeon did one technique, another surgeon did a different one so that each surgeon decided preoperatively what he felt would be the best shunt? Additionally, looking at postoperative risk factors and showing that the Aristotle scores are equal does not have the same validity as a prospective randomized trial to reach the conclusion as you have reached. So even though I would like to agree with your conclusion, I think we have to be very careful how we interpret these data. Dr Photiadis: You are absolutely right, but again, randomisation may not give you the whole answer. If we have a patient, say aortic atresia, mitral atresia, who is stable preoperatively and whom you randomly assign to the Sano shunt, and then you have another patient with aortic atresia and mitral atresia, same anatomic type, was not prenatally diagnosed, decompensation without closure of the duct and cannot be stabilised, if you look on just the anatomic type, they are the same, but with respect to preoperative risk in fact they are not. By means of the Aristotle score these differences can be detected, with one patient being assigned to the low-risk and the other one to the high-risk group.

Interruption of the aortic arch and hypoplastic left heart syndrome in the same patient is exceptional. In the combined collections of the Registry of Cardiovascular Disease (St. Paul, Minnesota, U.S.A.) and the Registry of Congenital Heart Defects of the Rijksuniversiteit Gent (Gent, Belgium) three specimens were found with this unusual combination. These cases are herein described and compared with four similar cases previously reported in the literature.

This report briefly describes two cases of levoatriocardinal vein, in the setting of mitral atresia and a restrictive interatrial shunt, with clinical as well as echocardiographic features mimicking obstructive total anomalous pulmonary venous connection. One patient died of pulmonary hypertensive crisis, and the other survived the palliative procedures including the atrioseptectomy and pulmonary artery banding. The echocardiography, cine-angiocardiography, and magnetic resonance image for such an anomalous channel are presented. It is tempting to speculate that the thrombocytopenia and indirect hyperbilirubinemia be associated with the destructive consumption of thrombocytes and red blood cells in the serpentine levoatriocardinal vein.

A case of a previously unreported anomaly is presented in which absence of the aortic valve cusps, mitral atresia, a normal left ventricle, and an intact ventricular septum were diagnosed by cross sectional echocardiography. The development of a normal left ventricle, rather than the hypoplastic ventricle usually associated with mitral atresia, is explained by filling of the ventricular cavity via the regurgitant aortic valve.

Clinical, catheterization, and pathologic findings were recorded in a newborn infant with tuberous sclerosis and multiple cardiac rhabdomyomas that produced a clinical picture simulating mitral atresia and the hypoplastic left-heart syndrome. The clinical picture was due to a left atrial tumor that completely obstructed the mitral valvular orifice. Even if the diagnosis of left atrial tumor had been made, successful surgical correction was unlikely because of left ventricular rhabdomyomas, which produced severe subvalvular aortic stenosis and did not appear to be resectable. This case demonstrates the possibility that a hamartoma, such as a rhabdomyoma, occasionally can mimic the hypoplastic left-heart syndrome.

Three cases of persistent ostium primum coexisting with atresia of an atrioventricular valve (tricuspid atresia in one case and mitral atresia in two cases) are described. The presence of a persistent ostium primum in association with an atretic atrioventricular valve allows easy escape of blood from the atrium with an atretic valve. To our knowledge, this association of anomalies has not been previously reportd.

A case is described of mitral atresia, patent foramen ovale, subcristal ventricular septal defects (VSD), and dextro-transposition of the great arteries (d-TGA), coexisting with a normal-sized left ventricle and normal-sized great arteries in a 6 8/12-year old girl. The discussion is related to anatomic, embryologic, and surgical aspects of this particular condition, which, to our knowledge, has never been documented before.

Echocardiograms and angiograms of six infants with left ventricular hypoplasia were examined. Three observations were made: (1) A normal-sized aortic root echogram may be seen in infants with mitral atresia, intact ventricular septum and normally related great arteries. (2) A recognizable mitral valve echogram may be seen in mitral atresia. (3) The true echocardiographic left ventricular dimension may be exceedingly difficult to measure, the tendency being to overestimate it. Awareness of these pitfalls with aid in the echocardiographic diagnosis of left ventricular hypoplasia in infants.

The aortas in 41 specimeans of aortic atresia (ten with associated mitral atresia) were studied for the presence of coarctation of the aorta. The basic lesion, causing varying degrees of obstruction, was observed in 31 instances (75%), 24 minor, seven with major degrees of obstruction. In half, the aortic lesion lay proximal to the ductus, and in the majority of the remainder, opposite the ductus arteriosus. The location of lesion and degree of obstruction was essentially the same whether aortic atresia occurred alone or in association with mitral atresia. Angiography is a fairly reliable method of identifying coarctation associated with aortic atresia. An additional point of interest was that in aortic atresia alone there was strong dominance of the male sex, while this tendency was not observed when mitral atresia was associated with aortic atresia.

Four infants, three with transposition of the great arteries and one with mitral atresia and single ventricle, who did not improve following balloon atrial septostomy are presented. Each p...

In an infant with mitral atresia and an almost imperforate atrial septum a collateral venous channel provided a pathway through which pulmonary venous blood was carried to the systemic venous system. The collateral channel started at the upper left pulmonary vein and connected with the left innominate vein. Similarities between this case and the one in the literature are emphasized. In the latter, the collateral channel began at the left atrium and terminated in a systemic vein derived from the cardinal venous system, hence the name levoatriocardinal vein. The case emphasizes the point that angiocardiographic demonstration of an anomalous pulmonary venous channel does not preclude the presence of an underlying serious intracardiac obstructive lesion as mitral atresia with inadequate interatrial communication. Roentgenographic evidence of pulmonary venous obstruction and cardiac enlargement should suggest this possibility.