Double Ventricular Pacing in a Patient with a "DDD" Universal Pacemaker

A patient with a DDD universal pacemaker presented with dyspnea. The electrocardiogram showed pacing artifacts both at the start of the QRS complex and 110 ms later. Also, 400 ms following sensed ventricular extrasystoles, there were normal single paced QHS complexes of slightly different morphology. An x-ray showed that the atrial electrode had displaced into the ventricle, and at exploration this was found to be due to late retraction of the electrode's active fixation helix. Following implantation of a new atrial lead, normal DDD pacing function was restored and the patient became asymptomatic.     

Prenatal sonographic delineation of the complex cardiac anatomy of thoraco-omphalopagus twins.

We describe a case of thoraco-omphalopagus twins diagnosed at 18 weeks' gestation. Each twin had a separate set of anatomical structures except for a shared heart, upper liver and anterior chest wall. The heart was located at the center of the juncture, and consisted of three atria and two ventricles, each twin having a single ventricle and right atrium but a fused left atrium. A set of great arteries originated from each single ventricle and there was juxtaposition of the aortic and pulmonary valves. One twin had transposition of the great arteries, whereas in the other these were normal in configuration. There was only one umbilical cord which contained four vessels (two arteries and two veins). This case report demonstrates the possibility of using fetal echocardiography to delineate the cardiovascular complex of the conjoined heart.     

Serial Lead Impedance Measurements Confirm Fixation of Helical Screw Electrodes During Pacemaker Implantation

The purpose of this study was to determine whether serial measurements of helical screw pacemaker lead impedance could reliably confirm electrode fixation in the right atrium and right ventricle. Fixation is generally assessed fluoroscopically, which can be misleading because the myocardium is radio lucent. Alternatively, because the electrical conductivity of blood is greater than that of myocardium, serial measurements of the lead impedance might be expected to show an impedance increase with appropriate fixation of the pacemaker electrode when the electrode becomes embedded in myocardial tissue. Impedance measurements were made during the placement of 23 atrial and 28 ventricular active fixation electrodes in 31 consecutive patients. Impedance measurements were recorded in unipolar and bipolar electrode configurations with the electrode free floating in the chamber, unfixed (with exposed screws) but touching the endocardial surface, and after fixation. No significant impedance differences were found between free-floating and unfixed electrode positions. With fixation, the lead impedance increased significantly in the ventricle (P = 0.0001, unipolar and bipolar) and the atrium (P = 0.0069 unipolar and 0.0052 bipolar). Typical increases, reflected by median values, were 197 ohms unipolar and 203 ohms bipolar in the ventricle and 47 ohms unipolar and 53 ohms bipolar in the atrium for electrodes with permanently exposed or retractable screw designs. Comparing serial measurements of lead impedance before and after electrode fixation is a valid electrical method of confirming appropriate fixation of helical screw electrodes.     

The Use of Active Fixation Electrodes for Permanent Endocardial Pacing Via a Persistent Left Superior Vena Cava

Two patients underwent permanent endocardial pacing for complete atrioventricular block. In each case a persistent left superior vena cava was either suspected or known to be present. An active fixation electrode was passed down the left superior vena cava and the tip positioned in the apex of the right ventricle. Stable ventricular pacing was achieved for the follow-up period of approximately six months. With the availability of such active fixation electrodes the presence of a persistent left superior vena cava no longer mandates insertion of an endocardial electrode via the right superior vena cava. when present, or implantation of an epicardial pacing system. (PACE, Vol. 5, March-April, 1982)     

Dynamic outflow tract obstruction in congenitally corrected transposition of the great arteries

Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease, constituting 0.5% of all congenital heart defects. The incidence of left ventricle (non-systemic ventricle) outflow tract obstruction ranges between 44 and 57%. Herein, we present the case of a 45 year old woman with CCTGA with progressively worsening dyspnea who had been referred for surgical correction of severe systemic ventricle (morphologic right ventricle) atrio-ventricular valve (tricuspid valve) regurgitation. Cardiac magnetic resonance imaging (CMR) and transesophageal imaging (TEE) demonstrated severe systemic ventricle (morphologic right ventricle) contractile dysfunction, as well as dynamic non-systemic ventricle (morphologic left ventricle) outflow tract obstruction due to systolic anterior motion (SAM) of the non-systemic ventricle (morphologic left ventricle) atrio-ventricular valve (mitral valve) with a large membranous ventricular septal aneurysm that protrudes into the outflow tract of the non-systemic ventricle (morphologic left ventricle). Ultimately, our patient was felt to be too high-risk for surgical correction and a course of medical therapy has been pursued.     

Transvenous Dual Chamber Pacing via a Unilateral Left Superior Vena Cava

A 74-year-old woman with a unilateral left superior vena cava required dual chamber permanent pacing after a radical cardiac operation for an incomplete form of endocardial cushion defect. An active fixation ventricular lead was used to prevent the instability induced by the strange course of the electrode. For atrial pacing, a ventricular passive fixation lead was used. A transvenous dual chamber pacemaker was successfully inserted via a unilateral left superior vena cava.     

Right ventricular septal pacing via transmural approach for resynchronization in a child with postoperative heart block

An infant with transposition of the great arteries was paced for postoperative heart block (single-site, right ventricular [RV] epicardial). She developed severe left ventricular (LV) dysfunction and septal dyskinesis. Resynchronization was performed at the age of 4 with an LV epicardial lead and an RV septal endocardial lead. The endocardial lead was affixed to the interventricular septum, then tunneled through the RV free wall and attached to an abdominal pulse generator. QRS duration decreased (176 to 122 ms) and LV ejection fraction improved (26 to 61%) and remained stable for 8 years. We present a case of successful resynchronization in congenital heart disease using a transmural RV septal lead.     

Two-dimensional echocardiographic features of double outlet left ventricle

In a cyanotic newborn infant, the diagnosis of double outlet left ventricle was made from the two-dimensional echocardiographic examination. The diagnosis was later confirmed at cardiac catheterization and surgery. The parasternal and subcostal views were especially useful for identification of the origin of both great arteries from the morphologic left ventricle. A review of the medical literature since 1967 revealed 77 cases of double outlet left ventricle, most of which were diagnosed only at surgery or postmortem examination. The anatomic features demonstrated with two-dimensional echocardiography in this case are representative of the findings cited most often in the cases reported in the medical literature.     

超声心动图评价大动脉调转术患者冠状动脉解剖类型

目的 评估超声心动图诊断大动脉调转术(ASO)患者冠状动脉解剖类型的准确性,总结超声观察冠状动脉位置及走行的方法.方法 2007年3月至2008年3月共50例患儿单纯依靠超声心动图检查确诊后行ASO,术前超声均对冠状动脉的解剖类型进行了评估,与术中所见进行对比.其中完全型大动脉转位(TGA)23例,右室双出口大动脉关系反位型(DORV)20例,矫正型大动脉转位(CTGA)2例,左室双出口大动脉关系反位型(DOLV)1例,完全型大动脉转位合并完全型肺静脉异位引流2例(TGA+TAPVC),完全型大动脉转位合并肺动脉瓣及瓣下狭窄(TGA+PS)2例.结果 50例患者中,冠状动脉发育正常40例,冠状动脉畸形10例.除2例因声窗条件差未能诊断冠状动脉解剖类型外,其余48例均能显示出冠状动脉的起源及走行方向,总可显示率为96.0%.与术中所见对比,48例患者超声诊断总正确率为95.8%.其中,冠状动脉正常者除1例因声窗条件未能显示冠状动脉外,其余均诊断正确.10例冠状动脉畸形包括单冠畸形4例;两支冠状动脉起自一个冠状窦2例;左冠状动脉前降支起源于右冠状窦2例;两支冠状动脉起源于相邻两个冠状窦,开口位于冠瓣交界两侧2例.其中1例因声窗限制未能诊断,2例诊断与术中有出入.冠状动脉畸形超声诊断准确率为77.8%.结论 通过多切面扫查,超声心动图能够准确诊断绝大部分ASO患者的冠状动脉解剖类型,为ASO提供全面而准确的诊断信息.     

Successful Long-Term Ventricular Pacing Via the Coronary Sinus After the Fontan Operation

A man with double inlet left ventricle and severe subpulmonary stenosis underwent a Fontan operation at the age of 29 years. Eight years later he developed atrial flutter with complete heart block. To avoid a further thoracotomy, a unipolar carbon tipped electrode was placed into the posterior cardiac vein via the coronary sinus. More than 8 years after implantation of the original lead, and after two generator changes, telemetric thresholds remain between 1.8–2.1 volts. Percutaneous transvenous ventricular pacing via the coronary sinus can produce an excellent long-term result and should be the initial approach of choice after a Fontan-type operation.     

Congenitally corrected transposition of the great arteries: MDCT angiography findings and interpretation of complex coronary anatomy

A 56-year-old male patient was admitted to our hospital because of dyspne and chest pain. A chest radiograph showed mild cardiomegaly. Echocardiography revealed unusual chamber in the heart. The chamber beneath the left atrium was morphologically right ventricle. To evaluate the precise complex anatomy of this abnormality, multidetector computed tomography (MDCT) angiography was performed. MDCT clearly revealed complex intracardiac and vascular anatomy, including typical imaging findings of a patient with congenitally corrected transposition of the great arteries (CCTGA). We described both imaging findings of MDCT angiography and interpretation of complex vascular anatomy in a patient with CCTGA.     

Two-dimensional echocardiographic diagnosis of double outlet left ventricle with subaortic ventricular septal defect, pulmonary stenosis, and a hypoplastic left ventricle.

Double outlet left ventricle (DOLV) is a rare congenital cardiac malformation in which both the pulmonary artery and the aorta arise exclusively or predominantly from the morphologic left ventricle. We describe a case of DOLV with situs solitus, d-loop ventricles, d-malposition of the great arteries (S, D, D), severe pulmonary stenosis, and a subaortic ventricular septal defect in which the left ventricle was also severely hypoplastic. The anatomic features were shown with 2-dimensional echocardiography, and the diagnosis was later confirmed at cardiac catheterization. Many morphologic variations of this malformation have been described but to the our knowledge DOLV with a hypoplastic left ventricle has not been reported before.     

Applying heart failure guidelines to adult congenital heart disease patients

There is a growing population of adult patients with congenital heart defects in the developed world. Most have been repaired, but few have been cured. Many have myocardial dysfunction. Most have exercise intolerance. Some have heart failure. As a group, they show neurohormonal activation similar to that seen in an adult heart failure population with acquired heart disease. Currently, the patients at greatest risk of heart failure are those without a systemic left ventricle, such as Mustard and Senning repairs of transposition of the great arteries (TGA), congenitally corrected TGA, and patients who have had a Fontan procedure. Exercise intolerance may predict hospitalization and death in such patients. For those patients with systemic left ventricles, it would seem reasonable to use the heart failure guidelines developed for patients with acquired heart disease. For those patients without a systemic left ventricle (e.g., a systemic right ventricle or single ventricle), there is currently no foundation for evidence-based therapy.     

Cardiovascular anomalies associated with prenatal exposure to theophylline

Theophylline has been shown to be a potent cardiovascular teratogen in animals, but there has been no evidence linking theophylline with congenital anomalies in infants. The cardiovascular anomalies in our three patients were aortic anomalies, double-outlet right ventricle, transposition of the great arteries, total anomalous pulmonary venous connection, and hypoplasia of the left ventricle. Some of these rare defects were also induced frequently in animal experiments with theophylline, which suggests that this drug can be a cardiovascular teratogen in a susceptible human fetus.     

Prenatal diagnosis of ventriculocoronary fistula.

BACKGROUND: Cardiac anomalies may be associated with abnormal coronary vascular connections. We report the prenatal diagnosis of ventriculocoronary fistula in three fetuses with associated cardiac anomalies. MATERIALS AND METHODS: Fetal echocardiography was performed in three patients referred for suspected cardiac anomaly. Two-dimensional fetal echocardiography was complemented by color Doppler flow imaging and spectral Doppler in all cases. RESULTS: A ventriculocoronary fistula was diagnosed in three patients referred at 22, 23 and 32 weeks. The first patient had hypoplastic left heart associated with transposition of the great arteries and pulmonary atresia with an intact interventricular septum. The coronary fistula arose from the transposed aorta to the left ventricle. In two patients ventriculocoronary fistula was found in association with pulmonary atresia and an intact interventricular septum. In all cases there was bidirectional flow within the fistula (diastolic blood flow towards the ventricle with reversal during ventricular systole). The pregnancy with hypoplastic left heart with transposition, and one of those with pulmonary atresia resulted in neonatal death and stillbirth, respectively. In the third instance the ventriculocoronary fistula was verified by postpartum cardiac angiography. The infant initially received a Blalock-Taussig shunt, subsequently replaced by a bidirectional Glenn shunt, and was doing well at the time of writing. CONCLUSION: A ventriculocoronary fistula can be identified prenatally by color and spectral Doppler. This anomaly should be sought in fetuses with outflow tract obstructive cardiac lesions and an intact interventricular septum. Prenatal diagnosis allows early angiography postnatally. Delineation of coronary vascular regions may therefore facilitate preoperative planning.     

胎儿完全性大动脉转位产前超声诊断简

目的探讨超声对胎儿完全性大动脉转位的诊断价值。方法回顾性分析2010年3月至2013年7月北京协和医院4例胎儿完全性大动脉转位的产前超声表现,并与病理结果进行比较。结果4例完全性大动脉转位胎儿中,3例四腔心切面正常,1例可见室间隔缺损。左室及右室流出道切面4例胎儿可见心室与大动脉连接关系异常,2例可见室间隔膜部缺损。三血管气管切面4例均仅可见2条血管。结论完全性大动脉转位具有特征性超声表现,重点观察心室流出道切面及三血管气管切面有助于产前正确诊断。     

Transseptal Left Ventricular Lead Placement Using Snare Technique

Background: Coronary sinus (CS) lead placement for cardiac resynchronization therapy has a failure rate of ～5–10%. Here we describe a way of implanting an endocardial left ventricular (LV) lead via a transseptal puncture (TSP), using a GooseNeck snare and active fixation lead. Methods: Three male patients (67–83 years) with failed or extracted epicardial LV leads implanted via the CS had an endocardial LV lead implanted. TSP was performed via a femoral vein. The active fixation pacing lead was advanced to the right atrium from a subclavian vein. A GooseNeck snare was passed via the TSP sheath and used to grasp the tip of the pacing lead. The sheath, GooseNeck snare, and pacing lead tip were then passed to the left atrium by sliding the system up the TSP guidewire and across the interatrial septum before deflecting the lead to permit implantation in the left ventricle. Results: Successful implantation was performed in all patients with an LV implant time of 25–55 minutes. Conclusion: The use of a GooseNeck snare via a deflectable transseptal sheath represents a reliable alternative method for endocardial LV lead placement in patients with failed CS LV lead implantation. (PACE 2012; 35:1248–1252)     

Micra implantation in a patient with transposition of great arteries

We describe a 56‐year‐old male with transposition of the great arteries and Mustard repair, superior vena cava obstruction, atrial fibrillation, and progressive deterioration of his epicardial lead performance. We were successful in deploying of Micra (Medtronic, Minneapolis, MN, USA) at the septo‐apical area of his nonsystemic ventricle in a stable position with satisfactory pacing and sensing thresholds.     

Antitachycardia Pacemaker Treatment of Postoperative Arrhythmias in Pediatric Patients

An automatic antitachycardia pulse generator (Intertach 262–12) was implanted in each of six pediatric patients (mean age, 10 years) with drug-resistant and persistent postoperative supraventricular arrhythmias. Four had bradycardia-tachycardia syndrome, two after a Mustard procedure for transposition of the great arteries, one after a Senning procedure for the same anomaly, and one after a Fontan procedure for univentricular heart with transposition of the great arteries. Of the two remaining patients, one had atrial flutter after a modified Fontan procedure for univentricular heart and one had intra-atrial reentry tachycardia after a modified Fontan procedure for double-outlet right ventricle with pulmonary stenosis. During a mean follow-up interval of 31 months after implantation, pacemakers were activated on multiple occasions and functioned appropriately in all six patients. Complications necessitated six invasive interventions in three patients: erosion or infection of the system, adaptor fracture, and connector block fracture on one occasion each and lead dislodgment on three occasions. Four of the six patients continued to take drugs at the end of this study; however, all patients had their drug therapy reduced and one was taking digoxin only. The number of hospital admissions decreased after implantation. Despite a number of technical challenges, this newer multiprogrammable antitachycardia pacemaker appears to be a valuable addition to the treatment of refractory postoperative supraventricular tachyarrhythmias in pediafric patients.     

Biventricular device implantation in a patient with congenitally corrected transposition and left-sided superior vena cava

An increasing number of patients with congenital heart disease are surviving into adulthood and some have indications for device therapy. Complex anatomical abnormalities may hinder the operator and require the adaptation of standard implantation techniques. We present the first report of successful biventricular ICD implantation in a patient with mesocardia, congenitally corrected transposition of the great arteries, pulmonary atresia, and a left superior vena cava draining into the coronary sinus. This case posed challenges in lead placement due to both complex anatomy and the risk of inappropriate device therapies secondary to far-field oversensing .