Atrial Septal Defect ASD

Supraventricular arrhythmias, particularly atrial flutter, are very common in patients with an ASD. In those who have not had surgical correction, arrhythmias are seen in 30-40 of patients by the age of 35 years. Atrial flutter in these patients is often ''typical'', i.e. dependent on conduction through a critical isthmus between the tricuspid annulus and inferior vena cava, and the activation wavefront may circle in either a counterclockwise or clockwise direction (Chan et al., 2000). In the...

Tetralogy of Fallot TOF

Most patients with TOF survive into adulthood with palliative or corrective surgery (Murphy etal., 1993). Patients with repaired TOF are at risk for both atrial and ventricular arrhythmias (Roos-Hesselink et al., 1995 Lucron etal., 1999). Following surgery, patients may have scarring of the right atrium from an atriotomy, and right ventricular scar from a ventriculotomy or ventricular outflow tract patch. In addition, residual haemodynamic lesions, such as RV dilatation caused by chronic...

Transposition of the Great Arteries

Atrial arrhythmias in patients with Mustard or Senning procedures are primarily IART secondary to a macro-re-entrant circuit developing around areas of scarring (Hayes and Gersony, 1986 Kanter etal., 2000). IART has been seen in around 10 at 5 years and 30 at 20 years of age, and often occurs in association with sinus node disease (Deanfield etal., 1988). Risk factors for flutter and IART include the occurrence of perioperative bradyarrhythmia, need for reoperation and sinus node dysfunction...

Functional Single Ventricle and Fontan Operation

The Fontan procedure offers surgical palliation to patients with a functional single ventricle. The primary arrhythmia following the atriopulmonary Fontan operation is IART, with atrial fibrillation also seen, but less frequently (Triedman, 2002). Retrospective studies from large cardiac surgical centres indicate that 25-50 of patients who have undergone the Fontan procedure will have clinical documentation of IART by 10 year follow-up. Frequently identified risk factors for IART include older...

Case Selection And Preparation

Knowledge of individual anatomy is essential when planning electrophysiological intervention. Review of the surgical case notes will allow assessment of the potential anatomical barriers for arrhythmia circuits and central obstacles for re-entry, such as atriotomy scars and patches. Documentation of clinical tachycardias via 12 lead electrocardiograms or Holter recordings is required to determine arrhythmia mechanisms and allow effective targeting of the arrhythmia substrate. Imaging...

Ventricular Tachycardia

Patients with ventricular dilatation, fibrosis or previous operative intervention are at risk of developing ventricular tachycardia. This is particularly seen in the patients with TOF who have undergone patch reconstruction of the right ventricular outflow tract (Lucron et al., 1999). Advanced mapping techniques are used to identify re-entry loops and corresponding channels between areas of scarring. Complex circuits may require ablation at several sites around the re-entrant zone to block all...

Surgical Procedures

16 Systemic-to-Pulmonary Artery Shunts, C. vanDoorn and M. R. de Leval . . . 251 Indications, 251 Disadvantages, 251 Surgical Technique, 251 Classical Blalock- Taussig Shunt, 251 Potts Shunt and Waterston Shunt, 254 Prosthetic Systemic-Pulmonary Artery Shunt, 255 Results, 259 17 Pulmonary Artery Banding, V. T. Tsang and J. Stark 261 Classical Indications, 261 Current Indications, 261 Ventricular Septal Defect, 261 Transposition of the Great Arteries, 262 Double-inlet Ventricle and Tricuspid...

Pulmonary Atresia

Pulmonary atresia is defined as a lack of continuity between the RVOT and the central pulmonary arteries, with a variable degree of hypoplasia of these structures. Pulmonary atresia is separated into two groups those with and those without a VSD. As the diagnosis and subsequent management of these two groups is different, it is useful to consider them separately. Pulmonary atresia with a VSD is the most common variant and is considered by some to be a severe form of ToF, with a subaortic VSD,...

Arterial Cannulation

The site of arterial cannulation will vary, depending on the requirements of the individual operation and the morphology of the circulation. Some situations are obvious, e.g. if the surgeon is to operate on the aortic root, the cannula should be positioned as distally as possible. However, more subtle positioning is also helpful. In an operation for tetralogy of Fallot, most of the surgical procedures take place on the right ventricular outflow tract or the pulmonary arteries, to the left of...

Pericardial Cavity

The heart is enclosed by a firm, fibrous sac, the pericardium. In functional terms, the pericardium consists of a tough bag that encloses the heart. The heart is placed into it from the base toward the apex, and the bag is subsequently closed by the fibrous layer merging at the cardiac base with the adventitial layers of the veins that enter and the arteries that leave the heart. In anatomical terms, the pericardium is a much more complex structure. This is because a second sac, the serous...

Congenitally corrected transposition ccTGA

This rare disorder is characterized by atrio-ventricular and ventricle-arterial discordance (right atrium to left ventricle to pulmonary artery and left atrium to right ventricle to aorta). Congenitally corrected transposition may be asymptomatic and in some patients is an incidental finding (Figure 5.17). However, the majority of patients with ccTGA have associated cardiac lesions (Bjarke and Kidd, 1976), such as VSDs, pulmonary stenosis or tricuspid valve abnormalities. Even without...

Straddling Left Atrioventricular Valves

A straddling left atrio-ventricular valve can be found in two distinct situations. The first is when the valve is of mitral structure, and is connected to a left-sided morphologically left ventricle and also to a right-sided morphologically right ventricle. This arrangement is basically that of concordant atrio-ventricular connections, but when the straddling valve is committed mostly to the ventricle receiving the other valve, then there is effective double-inlet right ventricle with...

Closed Cardiac Operations

Approximately 25 of cardiac surgery for congenital disease is performed without bypass, usually via a thoracotomy for procedures such as ligation of persistent ductus arteriosus, relief of coarctation of the aorta, formation of Blalock-Taussig shunts and banding of the pulmonary artery. Many of the patients are very cyanosed and or in severe heart failure. Some may require preoperative intensive care with respiratory and cardiac support. Levels of monitoring, vascular access and induction and...

R H Anderson and A E Becker

The purpose in this chapter is to show the anatomical variation that can exist in communications between ventricles, and to show how this variation relates to the atrio-ventricular and ventriculo-arterial connections that are present. In each example, we will describe the surgical anatomy of the conduction tissues. The key for various parts of the conduction tissues as they are superimposed on photographs is illustrated in Figure 8.1. Note the different conventions used for the right and left...

Angioplasty

Experiments establishing the basis for balloon angioplasty were performed in the early 1980s (Lock et al., 1981,1982). In those experiments, the balloon dilatation of experimental pulmonary artery stenoses was responsible for medial and intimal tearing, leading to the increase of vessel size, which reflects the efficacy of the procedure. Since then, balloon catheters have been used to dilate various vascular lesions, either congenital or postoperative. Balloon dilatation of aortic coarctation...

The Cardiac Skeleton

The fibrous skeleton is variably developed around the atrio-ventricular junctions, being strongest at the central fibrous body (Figure 2.37). There, the attachments of the leaflets of the mitral, tricuspid and aortic valves all meet together. Part of the fibrous body in this position also forms the membranous portion of the cardiac septum. Because of the differing positions of attachments of the leaflets of the mitral and tricuspid valves to the central fibrous body, and because of the wedge...

Velocityencoded Phase Contrast MR

Quantification of blood flow and velocity is an important tool in the management of congenital heart defects. Quantification of the pulmonary to systemic blood flow ratio (Qp Qs), valvular regurgitation fraction or vascular stenosis is used to assess disease progression, suitability for surgery and timing of surgery. Velocity-encoded phase contrast MR enables non-invasive quantification of blood flow and velocity in major vessels. Cardiac output and Qp Qs measured using this technique compare...

Ultrafiltration Uf

Modified Ultra Filtration Circuit

The increasing use of CPB in the neonatal period with haemodilution has exposed the tendency toward massive capillary leakage in these patients. Such capillary leakage can result in organ oedema and dysfunction and potentially fatal results. This problem reawakened interest in ultrafiltration, which was used in adult cardiac surgery for some time for removal of water from patients in chronic heart failure or for haemoconcentration towards the end of bypass. In conventional ultrafiltration...

Atrial Flutter and IART

If the typical flutter isthmus is involved in the reentry circuit, the area between the tricuspid valve (TV) and IVC is targeted for ablation (Figure 10.3). It is relatively narrow and in most patients good ablation catheter-tissue contact is achievable, although furrows and ridges may reduce tissue penetration with RF energy. Complete bidirectional conduction block across the flutter isthmus is the end point for ablation. IART may be re-entrant around a right atriotomy scar or, less usually,...

Junctions Between The Cardiac Segments

Types of Atrio-ventricular Connection There are several ways in which the atrial chambers can be joined to the underlying ventricular mass (Tynan et al, 1979), as illustrated in Figure 1.5. We describe the way in which the atrial and ventricular muscles masses are joined together as the ''types of atrio-ventricular connection''. In this respect, it should be noted that the normal heart, and many malformed hearts, possess two atrio-ventricular junctions. Thus, connections are usually plural....

Table 136 Basic principles of arrhythmia management for the intensivist

Ensure preoperative and immediate postoperative 12-lead ECGs have been recorded for later comparison Discuss patients with complex arrhythmia histories with an electrophysiologist prior to surgery Discuss any incidents of perioperative arrhythmias and precipitating factors with surgeon and anaesthetist Ensure abnormalities of plasma electrolytes are corrected Obtain a 12-lead ECG of arrhythmia prior to antiarrhythmic drug administration Record ECG after any subsequent interventions including...

Permanent Systems

The procedure requires X-ray fluoroscopy with a C arm and is performed in a catheter laboratory or a pacing theatre. Sterility is paramount and it is important to empower all members of the multidisciplinary team to point out areas of concern. We perform our procedures under general anaesthesia with a 24 hour course of anti-staphylococcal antibiotics starting at induction. Adult centres use basal sedation and local anaesthesia. Use of antibiotic cover is not universal but is very common....

In Doubleoutlet Ventricle

In hearts with double-outlet ventriculo-arterial connection, the hole between the ventricles forms the only egress for one of them. This hole, however, is not the space around which the surgeon secures a patch. It is important to appreciate this fundamental difference between interventricular communications in hearts in which each ventricle gives rise to a separate arterial trunk, and those in which there is a double-outlet ventriculo-arterial connection. The crucial feature in surgical repair...

Venous Reservoirs and Venous Drainage

Reservoir Pressure Heart

Blood drains from the patient via venous cannula into a venous reservoir before being pumped through the circuit. The reservoir acts as a holding tank, allowing fluctuations in the patient's circulatory volume to be tolerated. Figure 11.1 shows a diagram of the cardiopulmonary bypass circuit used at our department. Line 1 is the venous line from the right atrium or superior vena cava (SVC) to the venous cardiotomy reservoir (A). Line 2 is the venous line from the reservoir to the arterial pump...

Tetralogy of Fallot

Tetralogy of Fallot (ToF) is caused by malalignment of the infundibular septum, which leads to right ventricular outflow tract (RVOT) obstruction, a subaortic VSD with aortic override (Figure 5.6) and right ventricular hypertrophy. Current management consists of early single-stage reconstructive surgery, which has the benefit of leaving the patient acyanotic and has good survival rates. However, staged reconstruction may still be required under special circumstances (see Chapter 29). MR imaging...

Defects with Fibrous Continuity Between the Leaflets of the Aortic and Tricuspid Valves

These defects have conventionally been termed ''membranous defects'', but this can be a misleading term. As Becu et al. (1956) indicated, the defect is rarely caused by a deficiency of the interventricular component of the membranous septum. Indeed, during the development of the heart, the interventricular component is frequently not formed until after birth (Allwork and Anderson, 1979). The defect with fibrous continuity between the leaflets of the aortic and tricuspid valves results instead...

Identification Of The Cardiac Segments

Crista Supraventricularis

Atrial Situs (Atrial Arrangement) and Morphology Sequential segmental analysis can only work if structures are defined morphologically (Van Praagh, 1972 Anderson and Ho, 1997). This presents a problem only in relation to nomenclature of ventricles and the atrial chambers. Strict clarity demands that the words morphologically ''left'', or ''right'', ''ventricle'' or ''atrium'' should be used whenever these chambers are discussed and described, but this is somewhat cumbersome. For this reason,...

Anatomy Of The Ventricular Septal Defect In Tetralogy Of Fallot

Although the various types of ventricular septal defects found in tetralogy are comparable with isolated perimembranous, muscular or juxta-arterial defects that open to the outlet of the right ventricle, tetralogy is such a well-defined entity that the defects warrant separate consideration. We define ''tetralogy'' as the combination of a ventricular septal defect, subpulmonary infundibular stenosis, aortic overriding and right ventricular hypertrophy. The essence of the anomaly is cephalad...

Straddling Right Atrioventricular Valve

As with straddling of the left valve, this condition can also exist in two basic forms, each of which may produce basically univentricular or biventricular atrio-ventricular connections, depending on the degree of override of the atrio-ventricular junction. The first represents a spectrum between concordant atrio-ventricular connections with straddling tricuspid valve, and double-inlet left ventricle with right-sided rudimentary right ventricle and straddling right valve. The straddling valve...

Venous Cannulation

This is usually the method of choice for operations certain to involve circulatory arrest, or those in which the left side of the heart requires attention in the absence of intracardiac shunts. However, it is also preferred by some teams when low-flow bypass is required or when surgery on the inside of the heart is minimal e.g. the situation in the arterial switch procedure with intact ventricular septum . The choice of cannula is important for facilitating positioning within the right atrium...

Pulmonary Hypertension

Children with L-R shunts leading to pulmonary overcirculation or obstruction to pulmonary venous drainage pulmonary venous obstruction, mitral valve stenosis are at risk of developing pulmonary hypertension PHT Wessel, 2001 . PHT increases right ventricular afterload, potentially resulting in acute right ventricular failure, and may occur despite technically successful cardiac surgery. Pulmonary vascular reactivity has been related not only to the presence of preoperative pulmonary hypertension...

Quantitative Measurement

Atrioventricular Septal Defects And Echo

Echo measurement of ventricular shortening, wall thickness and cavity size remains a cornerstone of the assessment of ventricular function, hypertrophy or volume load. Figure 3.4, parasternal long axis in diastole, left, and systole, right, showing systolic apposition of the mitral valve and the septum as the mechanism of left ventricular outflow obstruction in hypertrophic cardiomyopathy . Contemporary clinical surgical decision making in many situations relies heavily on relatively simple...

Basic Rules Regarding Disposition Of The Conduction System

In any heart with a communication between two ventricles, application of a few basic rules enables fairly accurate prediction of the course of the conduction system. First, the regular atrio-ventricular node is always located at the apex of the triangle of Koch. Second, the branching atrio-ventricular bundle is positioned astride the crest of the muscular ventricular septum, regardless of whether that septum is aligned or malaligned relative to the atrial and muscular outlet septal structures....

Anatomy Of Cardiac Chambers

Triangle Koch Anatomy

To understand the spatial relationships of the different cardiac chambers, three basic rules of cardiac anatomy should be remembered. First, because of the orientation of the cardiac long axis, the ventricles are more or less to the left of their corresponding atrial chambers. Second, the right atrium and the right ventricle are relatively anterior to their left counterparts. Third, because of the anterior position of the chambers of the right heart, the aorta and its valve have a central...

P G Rees

Lillehei and colleagues devised a system of leaving at operation a wire attached to the ventricular epicardium and used it to pace the heart with a small external pacemaker system developed by Bakken Weirich etal., 1958 . In 1959, Elmquist and Senning described the first completely implantable pacing system involving the use of epicardial electrodes. At about that time, Furman and Robinson 1958 used endocardial leads introduced trans-venously. During the next few years...