Alternative technique for implanting an epicardial cardioverter defibrillation patch during a tricuspid valve replacement for arrhythmogenic right ventricular cardiomyopathy

Transvenous endocardial cardioverter defibrillator lead implantation is contraindicated in patients with prosthetic tricuspid valves (TVs). A 61-year-old male was hospitalized due to right heart failure, severe TV regurgitation, and non-sustained ventricular tachycardia (VT), which required Sotalol. The patient received an implantable cardioverter defibrillator (ICD) using an epicardial cardioverter defibrillation patch during a TV replacement (TVR) for VT and severe TV regurgitation because of arrhythmogenic right ventricular cardiomyopathy. There were no complications and the stimulation thresholds were stable. ICD implantation with the use of an epicardial cardioverter defibrillation patch serves as a safe, easy and effective therapy for patients undergoing TVR complicated with ventricular arrhythmia.     

The implantable cardioverter defibrillator:the end of the thoracotomy approach

Internal cardioverter defibrillator (ICD) implantation has become a standard therapy for life-threatening arrhythmias. A simple and safe surgical implantation technique is therefore mandatory in this high risk population. In a 30-month period 86 patients received 87 ICD devices. An endocavitary lead system was used as first choice in 62 patients and defibrillation thresholds (DFT) of 25 joules (J) or less were obtained in 57 patients. A thoracotomy approach was avoided using a biphasic shock wave form in 17 patients and the addition of a subcutaneous (sc) patch in 11 patients or wire array lead in 9 patients. There was one early non-technique related death (1.7%) after the transvenous approach. Reoperation was necessary in three patients with lead complications and in two patients for local device problems (one migration, one infection). With the recent progress in ICD technology, a thoracotomy approach could be avoided for the last 52 patients. For comfort and cosmetic reasons left subcostal insertion of the device has been successfully used in the last 50 patients. We conclude that the nonthoracotomy approach can now be offered to all patients in need for an ICD as a consequence of the technological progress made in the field of electric treatment of malignant ventricular arrhythmias. A stepwise approach with a minimum of implanted hardware and the use of biphasic shock systems now offers a simple and efficient treatment alternative with very low perioperative risk. Internal cardioverter defibrillator implantation in combination with open heart procedures can easily be avoided.     

A case of idiopathic ventricular tachycardia with ventricular fibrillation successfully treated with cryoablations and implantable cardioverter defibrillator]

A 16-year-old girl with medically refractory idiopathic ventricular tachycardia (VT) with ventricular fibrillation (VF) underwent cryoablations of the VT origin and received implantable cardioverter defibrillator (ICD). Intraoperative epicardial and endocardial mapping demonstrated the earliest activation site of VT in the infundibular septum of right ventricle. Cryoablations were applied through a pulmonary arteriotomy under mild hypothermic cardiopulmonary bypass with the heart beating. Because of the episodes of VF. ICD implantation was followed. Her postoperative course was uneventful and she remains free from VT and VF.     

Left ventricular pacing site-timing optimization during biventricular pacing using a multi-electrode patch

A 71-year-old man with class IV congestive heart failure and an infected pacemaker/implantable cardioverter defibrillator (ICD) underwent median sternotomy for removal of endocardial leads with a 15-mm vegetation. Cardiac output during biventricular pacing was optimized with an aortic flow probe, a multi-electrode left ventricular patch, and a randomized protocol assessing 54 combinations of pacing site and right ventricle-left ventricle delay. Results that were assessed with response surface methodology determined permanent epicardial lead position and timing. The difference between the best and worst site-timing combinations altered cardiac index by nearly 70%. This experience demonstrates potential importance of the epicardial approach to site-timing optimization for biventricular pacing.     

Feasibility of implantable cardioverter defibrillator treatment in five patients with familial Friedreich's ataxia--a case series

Friedreich's ataxia (FRA) is an autosomal recessive disease of the central nervous system that is associated with familial cardiomyopathy. Cardiac involvement is seen in more than 90% of the patients and is the most common cause of death in these patients. We present a case series and discuss the indications for implantable cardioverter defibrillator (ICD) implantation in FRA with review of the literature. Five pediatric patients who suffer from FRA (four female and one male, mean age 17.4 years) underwent ICD implantation between 2007 and 2008 in the University Hospital of Goettingen. The diagnosis of FRA was established by standard clinical criteria and proven in each case by genotyping at the frataxin locus. The time from diagnosis to ICD implantation was 10.4±1.73 years (range 8-15 years). All patients received transvenous lead systems. There were no intraoperative and postoperative complications. At the latest follow-up, the neuromuscular symptoms exhibited no further progress and no ICD activations were noticed. Only minor repolarization changes were seen on electrocardiogram. All patients had normal echocardiographic findings and no angina has been reported. Coronary angiographies were normal. It is evident that many FRA patients develop ventricular dysfunction. In the absence of a definitive surgical cure an ICD is generally indicated in young patients with hemodynamically significant sustained ventricular tachyarrhythmias for prevention of sudden cardiac death. Our experience implies the safe use of ICD in children with FRA.     

Anatomical Consideration for an Implantable Centrifugal Biventricular Assist System

Abstract: A miniaturized pivot bearing-supported centrifugal blood pump (Gyro PI) has been developed as a long-term biventricular assist system (BiVAS). In this study we determined the anatomical configuration of this system using a bovine model. Under general anesthesia, a left lateral thoracotomy was performed to open the chest. Two Gyro PI-601 pumps for left and right assists were placed in the preperitoneal pocket by a subcostal abdominal incision. The left pump could be placed along the dome of the diaphragm just beneath the apex of the left ventricle. The right pump could be placed next to the left pump. The inlet and outlet ports of both pumps penetrated the diaphragm. The inlet port of the left pump, with a length of 55 mm, was inserted directly into the apex of the left ventricle. A woven Dacron graft (150 mm long, 11 mm inner diameter) was placed between the outlet port of the left pump and the descending aorta. As for the right pump. a 100 mm long and 120 degree angled inflow conduit was placed between the inlet port and the right ventricular infundibulum. The outlet port of the right pump was connected to the main trunk of the pulmonary artery using a 90 mm long, 11 mm inner diameter Dacron graft. We could perform biventricular assistance to confirm the anatomical feasibility of the Gyro implantable centrifugal BiVAS.     

Anestesia para paciente com cardiomiopatia arritmogênica do ventrículo direito portador de cardioversor desfibrilador implantável: descrição de caso

Background and objectivesArrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic cardiomyopathy characterized by potentially lethal ventricular tachycardia. Here we describe a patient with ARVC and an Implantable Cardioverter Defibrillator (ICD) in whom maxillary sinus surgery was performed under general anesthesia.Case reportThe patient was a 59 year‐old man who was scheduled to undergo maxillary sinus surgery under general anesthesia. He had been diagnosed as having ARVC 15 years earlier and had undergone implantation of an ICD in the same year. Electrocardiography showed an epsilon wave in leads II, aVR, and V1–V3. Cardiac function was within normal range on transthoracic echocardiography. The ICD was temporarily deactivated after the patient arrived in the operating room and an intravenous line was secured. An external defibrillator was kept on hand for immediate defibrillation if any electrocardiographic abnormality was detected. Remifentanil 0.3 μg/kg/min, fentanyl 0.1 mg, propofol 154 mg, and rocuronium 46 mg were administered for induction of anesthesia. Tracheal intubation was performed orally. Anesthesia was maintained oxygen 1.0 L.min^‐1, air 2.0 L.min^‐1, propofol 5.0–7.0 mg.kg^‐1.h^‐1, and remifentanil 0.1–0.25 μg.kg^‐1.min^‐1. The surgery was completed as scheduled and the ICD was reactivated. The patient was then extubated after administration of sugammadex 200 mg.ConclusionWe report the successful management of anesthesia without lethal arrhythmia in a patient with ARVC and an ICD. An adequate amount of analgesia should be administered during general anesthesia to maintain adequate anesthetic depth and to avoid stress and pain.     

Surgical treatment of tricuspid regurgitation caused by L?ffler's endocarditis.

A 25-year-old man with a history of bone-marrow-transplantation for the treatment of L?ffler's endocarditis underwent surgery for massive tricuspid regurgitation with paroxysmal atrial flutter. Dense fibrosis in the right ventricular endocardium with complete obliteration of the apex was seen intraoperatively, and the right ventricular cavity was diminished. Annular dilatation of the tricuspid valve and entrapment of the posterior leaflet to the endocardial fibrosis were also seen. Annuloplication at the posterior leaflet was performed. In addition, the right atrial free wall was widely resected and the septal and inferior vena cava-tricuspid valve isthmi were cryoablated for the treatment of atrial flutter. Postoperative catheterization revealed rather high right ventricular end-diastolic pressure. However, tricuspid regurgitation disappeared with the increased cardiac output. Atrial flutter could not be induced by repetitive stimulation in the postoperative electrophysiological examination.     

Anesthetic management of a patient with severe dilated cardiomyopathy and an automatic implantable cardioverter-defibrillator (AICD) during total gastrectomy

We report a case of severe dilated cardiomyopathy with an automatic implantable cardioverter-defibrillator (ICD) undergoing total gastrectomy. During the operation, the defibrillation function of the ICD was suspended and its pacing function was used solely in VOO mode. Electrodes of an external defibrillator were attached on the chest wall, and a pulmonary arterial (PA) catheter with a ventricle pacing port was inserted into the pulmonary artery. Proper perioperative management, including measures that the patient underwent the surgery uneventfully and could attain a rapid and successful discharge from the intensive care unit.     

Biventricular pacing in a patient with severe congestive heart failure

We report a case of dilated cardiomyopathy with severe congestive heart failure (ejection fraction: 19%) and complete left bundle branch block (QRS duration: 240 ms) 13 years after aortic valve replacement. Permanent biventricular pacing was implanted by inserting a left ventricular lead thorough a small left thoracotomy following intravenous insertion of right atrial and ventricular endocardial leads. Biventricular pacing increased hemodynamic parameters such as blood pressure, cardiac output and decreased mitral regurgitation. Symptoms and exercise tolerance improved dramatically. Left ventricular epicardial lead insertion via a small thoracotomy is thus useful in selected patients.     

Comparison of internal cardioverter defibrillator implantation techniques: subpectoral position

BACKGROUND: To compare surgical techniques for subpectoral implantation of internal cardioverter defibrillator (ICD). METHODS: Sequential comparison with review of the literature. SETTING: University Hospital. PARTICIPANTS: the patients requiring ICD. INTERVENTIONS: ICD insertions and device testing. MEASUREMENTS: defibrillation and pacing thresholds, defibrillator lead impedance, operative time, and proximity of generator site to midline, clinical outcomes. RESULTS: Comparable efficacy in defibrillation, surgical time and medial placement. No wound infections, seromas or lead dislodgments. Preservation of pectoral muscle integrity. CONCLUSIONS: Lateral single incision subpectoral ICD generator placement can be applied consistently with good RESULTS.     

Surgical treatment of tricuspid regurgitation caused by Löffler’s endocarditis

A 25-year-old man with a history of bone-marrow-transplantation for the treatment of Löffler’s endocarditis underwent surgery for massive tricuspid regurgitation with paroxysmal atrial flutter. Dense fibrosis in the right ventricular endocardium with complete obliteration of the apex was seen intraoperatively, and the right ventricular cavity was diminished. Annular dilatation of the tricuspid valve and entrapment of the posterior leaflet to the endocardial fibrosis were also seen. Annuloplication at the posterior leaflet was performed. In addition, the right atrial free wall was widely resected and the septal and inferior vena cava-tricuspid valve isthmi were cryoablated for the treatment of atrial flutter. Postoperative catheterization revealed rather high right ventricular end-diastolic pressure. However, tricuspid regurgitation disappeared with the increased cardiac output Atrial flutter could not be induced by repetitive stimulation in the postoperative electrophysiological examination.     

Superiority of endocardial versus epicardial implantation of the implantable cardioverter defibrillator (ICD).

The implantable cardioverter-defibrillator (ICD) has proved to be an efficient device for the treatment of severe ventricular tachyarrhythmias (VT). From May 1985 to August 1991, the ICD was implanted in 107 patients of whom 72% suffered from coronary artery disease, 17% from cardiomyopathy, 5% from long QT-syndrome and 6% from other heart disease. All patients had a life threatening episode of VT or at least one episode of ventricular fibrillation. Of 107 implants, 12% were combined with other heart surgery, 55% were isolated epicardial implantations (epi I) and in 33%, the novel endocardial (endo I) approach was chosen. Between epi I and endo I we found no difference in operation time, but time for ICU and in-hospital stay was significantly shorter using the transvenous approach. In addition, sensing and pacing capability of the endocardial screw-in electrode was superior and the need for thoracotomy was avoided, a particular advantage in patients with previous heart surgery. Complications after epi I were: temporary low cardiac output, 1; perioperative death, 2; infection, 3, and after endo I: electrode dislocation, 2. Hence, endo I may become the method of choice for patients without concomitant surgery.     

Structure function interface with sequential shortening of basal and apical components of the myocardial band

Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’.     

An unusual localization of an infected urachal sinus

Failure of obliteration of the urachus in intrauterine life results in anatomically recognizable distinct anomalies. The urachus is located between the umbilicus and apex of the bladder. However, this anatomic feature does not always exist, and this may lead to misdiagnosis of the urachal pathologies. A 5-year-old boy with infected urachal sinus is presented. The urachus showed an unusual anatomic course with its extention from the umbilicus to the right lateral side of the bladder instead of the apex of the organ.     

An unusual travel of an endocardial pacing lead to the left ventricle

A 80-year-old lady was admitted because of dyspnea, complete AV block and ventricular rate of 15 bpm. A DDDR pacemaker was successfully implanted. Postoperative EKG showed right bundle branch block and X-ray the ventricular lead in the left ventricle. It traveled all the way through a foramen ovale being later relocated in the right apex.     

Anesthetic management of a patient undergoing cardioverter defibrillator implantation: usefulness of transesophageal echocardiography and near infrared spectroscopy

A case of a patient with sustained ventricular tachycardia (VT) undergoing implantable cardiovertor defibrillator (ICD) implantation, using transesophageal echocardiography (TEE) and near infrared spectroscopy (NIR) is described. A 67-year-old man with sustained VT associated with old myocardial infarction underwent ICD implantation. Anesthesia was induced with fentanyl and propofol and maintained with nitrous oxide, oxygen, sevoflurane, and fentanyl. Global hypokinesis of the left ventricle was observed in the short-axis view provided by TEE. Intraoperative systolic blood pressure was maintained between 100 and 120mmHg, and cerebral oxygenated hemoglobin (HbO2) was between 63% and 65%. During periods of induced ventricular fibrillation, systolic blood pressure decreased to 60mmHg, HbO2 decreased to 59%, and TEE revealed cardiac arrest. These changes were transient; HbO2 returned to baseline values immediately after the restoration of normal rhythm. TEE confirmed no remarkable change in cardiac function after defibrillation testing. TEE and NIR were found to be beneficial for the anesthetic management of a patient with sustained VT who was underdoing ICD implantation.     

The nature of the obstructive muscular bundles in double-chambered right ventricle.

OBJECTIVE: Our goal was to establish the morphologic nature of the obstructive muscular lesions in double-chambered right ventricle. METHODS: We based our morphologic observations on 10 normal hearts and on the surgical findings in 26 patients, aged 0.5 to 24 years, with a mean of 6.9 years (SD 5.8 years). In the normal hearts, we measured the distance from the pulmonary valve to the apex of the right ventricle and from the takeoff of the moderator band to the ventricular apex. From angiograms available in 20 patients, using the frontal view, we then measured the distance from the pulmonary valve to the apex of the right ventricle and from the midpoint of the obstructive lesion to the apex of the right ventricle. This permitted calculations of multiple ratios. RESULTS: In the 10 normal hearts, the moderator band took origin at a mean ratio of 0.48 (SD 0.16) of the ventricular length. On the basis of the angiographic findings, we identified 2 basic forms of double-chambered right ventricle. In 9 patients, the obstructive muscular shelf was positioned low and diagonally across the apical component, with a mean ratio of 0.38 relative to the ventricular length (SD 0.02). In the other 11 patients, the obstructive shelf was high and horizontal, with a mean ratio of 0.27 (SD 0.02). The difference was statistically significant (P =.001). Surgical repair was performed successfully in all 26 patients through a right ventriculotomy. CONCLUSIONS: Double-chambered right ventricle is the consequence of a high or low muscular division of the apical component of the right ventricle. The abnormal muscular bundle probably represents accentuated septoparietal trabeculations, rather than always being an abnormal moderator band.     

Human Thoracic Anatomy Based on Computed Tomography for Development of a Totally Implantable Left Ventricular Assist System

Abstract: Human thoracic anatomy was studied using computed tomography (CT) for the development of a totally implantable electrohydraulic left ventricular system [Nimbus, Inc., and The Cleveland Clinic Foundation (CCF)]. To obtain statistical dimensional information for the chest wall, apex of the heart, and aorta, routine calibrated CT scans of 18 men and 17 women were analyzed. A special radiopaque vest was worn by the patient just prior to the scanning and X-ray procedures, so that each transverse scan could be assigned to a specific chest level after combination with a standard vertical referencing system set on the patient's radiogram. A polar coordinate system and direct measurement of transverse distances from the vertical column to points on the chest wall were employed to define collectively the shape and size of the intrathoracic surface of the chest wall. Locations of the aorta and apex were described by measuring their normalized distances from the midline and vertical column to the intrathoracic surface of the lateral and anterior chest wall. The radius of curvature of the intrathoracic wall lateral to the left ventricle was determined to be ˜ 10.4 cm for the average adult male chest. The present CCF intrathoracic pump with this curvature fits fairly well in both the average and individual thoraxes of these adult males. The location of the aorta, particularly of the descending aorta, was used to determine the optimal outlet design. The most critical anatomical area was the apex location. For adult males, an average distance of 2.8 cm from the apex to the internal chest wall was found. Because of this small dimension, careful design of the inflow port is being performed to avoid anatomical mismatch.     

Comparison of epicardial and endocardial linear ablation using handheld probes

BACKGROUND: The optimal technique for producing linear radiofrequency thermal lesions in myocardial tissue is unclear. We compared epicardial ablation on the beating heart with endocardial ablation after cardioplegia. METHODS: Radiofrequency lesions were produced using a multielectrode malleable handheld probe in ovine myocardium with three wall thicknesses. Detailed analysis of lesion dimensions was used to assess the effects of site of ablation, muscle thickness, and duration of ablation. RESULTS: After epicardial atrial ablation, myocardial lesions were detected in all sections without macroscopically visible epicardial fat (n = 10), but only 43% (6/14) of sections with epicardial fat. Three of 24 atrial epicardial sections (13%) and 92% (23/25) of endocardial atrial lesion sections were clearly transmural. In thicker tissues lesion depth was independent of endocardial (right ventricle: 3.9 +/- 1.1 mm, left ventricle: 3.8 +/- 0.7 mm) or epicardial (right ventricle: 3.4 +/- 0.6 mm, left ventricle: 4.3 +/- 0.9 mm) ablation site. Epicardial lesions are less deep in thinner areas of myocardium (p = 0.003). Lesions were all wider than they were deep. There was no significant increase in lesion depth with the increase in ablation duration from 1 to 2 minutes. CONCLUSIONS: Lesions were unlikely to be transmural with either technique when the wall thickness was greater than about 4 mm. Epicardial fat has an important negative effect on epicardial lesion formation. Where epicardial fat is absent epicardially produced lesions penetrate less deeply when the wall thickness is small, possibly due to endocardial cooling by circulating blood. Prolongation of the duration of ablation from 1 to 2 minutes does not significantly increase lesion depth.