Transesophageal echocardiography for insertion of a physiological pacemaker in early pregnancy

Management of Complete Heart Block in a Pregnant Woman with Systemic Lupus Erythematosus-Associated Complications: Treatment Considerations and Pitfalls

We present a case of a pregnant woman with systemic lupus erythematosus (SLE) who was diagnosed with asymptomatic complete heart block (CHB) during pregnancy. To evaluate possible risks and benefits of pacemaker (PM) implantation, a multidisciplinary counselling board was held. Its recommendation was to perform PM implantation to prevent intra-uterine growth restriction from insufficient cardiac output using a fluoroscopic protective shield. The procedure was performed without complications and established permanent pacing on onwards ECG examinations. The patient subsequently gave birth to a healthy newborn. After a retrospective clinical case evaluation and review of relevant literature, a presumptive association between CHB and the primary diagnosis was proposed. Above that, pregnant women with SLE who develop hypertension are commonly treated with methyldopa, which may cause conduction abnormalities. Clinical recommendations for young female patients expecting pregnancy are lacking in this area. Careful diagnostic and treatment approaches should be used in the management of possible SLE-related complications in women of child-bearing age, focusing on preventable events.

[Bradycardia in pregnancy : Case report and review of the literature]

We report the case of a pregnant woman with complete heart block during her first trimester who presented with dyspnea at the East African Heart Rhythm Project in Nairobi. There was no evidence of an acute cause (e.g., myocarditis, cardiomyopathy, autoimmune or neuromuscular disease). No ECG had been previously documented; therefore, congenital complete heart block was likely. We implanted a dual-chamber pacemaker using conventional fluoroscopy. Several measures at implantation allowed us to limit fluoroscopy to 30 s and radiation to < 100 µGym². The implantation was uneventful, dyspnea improved instantaneously and further pregnancy, labor and birth were uncomplicated. Bradycardia requiring pacemaker implantation is rare during pregnancy and usually consists of symptomatic complete heart block. Beyond undiagnosed or untreated pre-existing atrioventricular block, drug therapy for fetal tachycardia, myocarditis (including Lyme borreliosis and Chagas disease), inflammatory infiltrative diseases (e.g., sarcoidosis), cardiomyopathies and neuromuscular disease may have caused bradycardia. In the absence of treatable causes, pacemaker implantation becomes necessary if bradycardia brings about risks for the mother or the fetus. Using transesophageal or intracardiac echocardiography, radiation can be avoided completely or, by taking some simple measures, may be kept to a minimum so that there is no risk for the fetus.

Progress in zero-fluoroscopy implantation of cardiac electronic device

Fluoroscopy is the imaging modality routinely used for cardiac device implantation. Due to the rising concern regarding the harmful effects of radiation exposure to both the patients and operation staffs, many efforts have been made to develop alternative techniques to achieve zero-fluoroscopy implantation. In this review, we describe the different methods aimed at avoiding the application of fluoroscopy in recent years, and evaluate their feasibility and safety in cardiac electronic device implantation.

CARDIAC ARRHYTHMIAS DURING PREGNANCY: A CLINICAL APPROACH

Physiologic changes in maternal haemodynamics, hormones and autonomic properties contribute to arrhythmias in pregnancy. While arrhythmias most commonly occur in pregnant women with structural heart disease or those with a history of cardiac arrhythmias, they can also occur de novo in women with no documented cardiac disease.

Transesophageal echocardiography and noncardiac surgery

The use of transesophageal echocardiography (TEE) for monitoring during cardiac and noncardiac surgery has increased exponentially over the past few decades. TEE has evolved from a diagnostic tool to a monitoring device and a procedural adjunct. The close proximity of the TEE transducer to the heart generates high-quality images of the intracardiac structures and their spatial orientation. The use of TEE in noncardiac and critical care settings is not well studied, and the evidence of the benefits of its use in these settings is lacking. Despite the widespread availability of TEE equipment in US hospitals, less than 30% of anesthesiologists are formally trained in the use of perioperative TEE. In this review, the safety and indications of TEE are reviewed and detailed analysis of the best available evidence in this regard is presented. Landmark trials evaluating the use of TEE and its therapeutic impact in noncardiac surgical setting are critically reviewed. This article details recommendations to familiarize anesthesiologists with TEE technology to exploit it to its fullest potential to achieve better patient monitoring standards and eventually improve outcome. Training of greater numbers of anesthesiologists in TEE is needed to increase awareness of the indications and contraindications. Until relatively inexpensive TEE equipment is available, the initial cost of equipment acquisition remains a significant prohibitive factor limiting its widespread use.

Arrhythmias in the pregnant patient: Current concepts in evaluation and management

Maternal arrhythmias during pregnancy may jeopardize the health of both mother and fetus. The correct identification of the arrhythmia is critical in the pregnant patient. Treatment should be reserved for arrhythmias that are hemodynamically unstable or cause debilitating symptoms. When medications are deemed necessary, the physician should use as few drugs as possible at the lowest effective doses and choose drugs with a history of safe use in pregnancy. Resuscitation of a pregnant patient in cardiac arrest should be modified with regard to the normal physiologic changes of pregnancy. With careful management, most of these challenging patients will have excellent outcomes.

Bradyarrhythmias in pregnancy: a case report and review of management

We present a case of unpaced pre-existing congenital heart block in pregnancy, diagnosed for the first time in labour. Our patient was asymptomatic and was managed conservatively with temporary pacing equipment on standby. She had a post-partum cardiology follow-up and was paced in the puerperium. We discuss the aetiopathogenesis and the variable presentation patterns of bradyarrhythmia in pregnancy and the multidisciplinary approach to their management. Our recommendations combine the Advanced Life Support algorithm for treatment of bradycardia and the successful management strategies of several documented case reports in the literature.

Transseptal left heart catheterisation guided by intracardiac echocardiography

OBJECTIVE

To develop a novel approach of transseptal puncture guided by intracardiac echocardiography and to assess its efficacy.

METHODS

Transcatheter intracardiac echocardiography with a 9 MHz rotating transducer was performed to guide transseptal puncture in 12 patients (mean age 43.1 years, range 31-68) who underwent radiofrequency catheter ablation of left sided accessory pathways. Initially, the echocardiography and transseptal catheters were placed adjacent to each other in the superior vena cava and were withdrawn to the level of the fossa ovalis.

RESULTS

The successful puncture site was associated with visualisation of the fossa ovalis (12 patients, 100%) and the aorta (12 patients, 100%), tenting of the fossa (six patients, 50%), penetration of the needle visualised by the ultrasound catheter (12 patients, 100 %), and echocardiographic contrast material applied in the left atrium (12 patients, 100%). The characteristic jump of the needle onto the fossa ovalis was observed simultaneously with fluoroscopy and intracardiac ultrasound (12 patients, 100%). All procedures were successful. There were no complications associated with the transseptal procedure.

CONCLUSIONS

Intracardiac echocardiography is feasible to guide transseptal puncture. The optimal puncture site can be assessed by simultaneous detection of the characteristic downward jump of the transseptal needle onto the fossa ovalis by intracardiac ultrasound and fluoroscopy.

Implantation of permanent dual chamber pacemaker in a pregnant woman by transesophageal echocardiographic guidance

A 37-year-old woman complained of fatigue and dizziness because of intermittent sinus arrest and asystole up to 5.2 seconds. She was 3 months into her pregnancy and a dual chamber permanent pacemaker was implanted by transesophageal echocardiographic guidance.

[Arrhythmias and pregnancy]

Although arrhythmias are one of the most frequent consultations during pregnancy, fortunately the majority are benign. Usually, they are well tolerated assuming they occur in patients with structurally normal hearts. However, pregnancy adds a new aspect to the so called "arrhythmia tolerance", because arrhythmia and therapy may jeopardize the fetus. For acute treatment of narrow and wide tachycardias, with few exceptions, antiarrhythmic medications appear to be safe. In addition to the relative security of drugs such as adenosine, digoxin, propranolol, procainamide and flecainide, we could use direct current countershock with no evidence of significant complications. Because no drug is absolutely safe, chronic pharmacologic therapy is best avoided during pregnancy. Finally, radiofrequency ablation could be recommended as an alternative in women with previous tachycardias who would like to become pregnant.

Identification of a malpositioned atrial pacemaker lead across a patent foramen ovale by transesophageal echocardiography

Transesophageal echocardiography was used for defining the unusual left atrial location of a malpositioned atrial pacemaker lead. This malpositioning occurred in a 75-year-old woman who had a small atrial septal aneurysm and a patent foramen ovale. Neither the precise location of the pacemaker lead tip nor the course of the lead was apparent by radiographic or transthoracic echocardiographic techniques. This report extends the potential utility of transesophageal echocardiography for the identification of malpositioned atrial pacemaker leads.

Echocardiographically guided electrophysiologic testing in pregnancy

Electrophysiologic testing is usually performed with fluoroscopy to guide catheter positioning. This method of visualizing catheter placement may not be ideal for patients who are pregnant. We report four cases of echocardiographically guided placement of catheters for electrophysiologic testing because of the consideration of pregnancy. Adequate visualization of catheters was possible, allowing for proper catheter positioning and complete electrophysiologic testing, including the recording of atrial, His-bundle, and ventricular potentials, as well as cardiac stimulation and induction of tachycardia. This method holds promise for patients in whom fluoroscopy may be relatively contraindicated, such as pregnant patients, as well as patients in whom it is desirable to avoid x-ray exposure such as women of childbearing age and young children.

Long-term follow up of patients treated with a software based antitachycardia pacemaker

INTRODUCTION

Over the past decade, several advances have been made in the management of tachycardias by pacing techniques, but limited data are available on the long-term outcome of patients treated with antitachycardia pacemakers.

PATIENTS AND METHODS

An antitachycardia pacemaker, the Intermedics Intertach, was implanted in 22 (17 female) patients with supraventricular tachycardia over a five year period. All were selected after detailed evaluation and testing of a temporary antitachycardia pacemaker system showed that their arrhythmia could be stopped promptly, reliably, and under different physiological conditions.

RESULTS

The 22 patients have been followed up for a mean period of 57.3 (range 19-76) months. All except one of the patients has had frequent episodes of tachycardia reliably ended by the pacemaker. Complications have occurred in seven patients, necessitating removal of the pacing system in four. Of the 18 patients who continue to have pacemakers, seven are being treated with beta blockers or verapamil; no other antiarrhythmic drugs are being taken.

CONCLUSIONS

Antitachycardia pacing is an acceptable long-term option for carefully selected patients with supraventricular tachycardia, but even after extensive testing a substantial number of the patients may continue to require drug treatment. Furthermore, the widespread use of curative techniques for supraventricular arrhythmias (catheter ablation and surgery) has decreased the need for this palliative treatment.

Transesophageal echocardiography to improve positioning of radiofrequency ablation catheters in left-sided Wolff-Parkinson-White syndrome

Two patients with the Wolff-Parkinson-White syndrome who underwent successful radiofrequency catheter ablation of their left-sided bypass tracts are described. Transesophageal echocardiography, a relatively new echocardiographic technique, was utilized in both patients and provided excellent visualization of intracardiac anatomy as well as the catheter tip. Transesophageal echocardiography was also synergistic with fluoroscopy and the intracardiac electrogram in providing more precise catheter placement. In addition, the use of transesophageal echocardiography may reduce fluoroscopic exposure and shorten the procedure time.