A Review of Temporary Permanent Pacemakers and a Comparison with Conventional Temporary Pacemakers.

Temporary cardiac pacing is commonly used in patients with life-threatening bradycardia and serves as a bridge to implantation of a permanent pacemaker (PPM). For years, passive fixation leads have been used for this purpose, offering the advantage of that they can be placed at bedside. The downside, however, is that patients must remain on telemetry and bed rest until lead removal due to the risk of displacement and failure to capture. Even then, the latter cannot always be prevented. Temporary cardiac pacing with passive fixation leads has also been related to a higher incidence of infection and venous thrombosis, delayed recovery, and increased length of stay. Thus, over the last couple of decades, pacemaker leads with an active fixation mechanism have become increasingly used. This is known as a temporary PPM (TPPM) approach, which carries a very low risk of lead dislodgement and allows patients to ambulate, among other advantages. Here, we performed a review of the literature on the use of TPPMs and their advantages over temporary pacemakers with passive fixation leads and in order to evaluate the advantages and disadvantages of active and passive fixation leads in temporary cardiac pacing. Most articles found were case reports and case series, with few prospective studies. We excluded documents such as editorials and image case reports that provided little to no useful information for the final analysis. The literature search was performed in PubMed, Google Scholar, and other databases and articles written in English and Spanish were considered. Articles were screened up to January 2017. The search keywords used were "temporary permanent pacemaker," "external permanent pacemaker," "active fixation lead," "explantable pacemaker," "hybrid pacing," "temporary permanent generator," "prolonged temporary transvenous pacing," and "semipermanent pacemaker." A total of 24 studies with 770 patients were ultimately included in our review. The age group was primarily above the sixth decade of life, with the exception of one that included pediatric patients. Indications for pacing included device infection, sick sinus syndrome, atrioventricular block, ventricular tachycardia, and bradyarrhythmias associated with systemic illness. The duration of TPPM usage varied from a few days up to 336 days. A total of 18 (2.3%) TPPM-related infections were reported, in which the duration of TPPM use was less than 30 days in at least 15 patients. Loss of capture was documented in only eight patients (1.0%). Complication rates varied from 0% to 30%, with the highest event rates being present in studies that used femoral venous access. In conclusion, although no high-quality studies were identified in our literature search, we found the data retrieved suggest the association of overall favorable outcomes with the use of TPPMs. Device placement and removal typically involve a simple procedure, although fluoroscopy, usually applied in the cardiac catheterization laboratory, is necessary for implantation, which could represent an additional risk in a patient who is already hemodynamically unstable. When possible, a screw-in-lead pacemaker should be used for temporary pacing.

Cardiac resynchronization therapy resulting from atrial pacing: An unusual case of intraventricular conduction delay.

Cardiac resynchronization therapy device implantation is complicated by a significant rate of failure to place a left ventricular lead via the coronary sinus. The present case describes one such failure ironically leading to resynchronization. The patient's QRS narrowing subsequent to postimplant atrial pacing alone suggests that bradycardia-dependent phase 4 block was the indirect but exclusive cause of the patient's intraventricular conduction delay. Thus, phase 4 block should be considered when atrial pacing at a faster rate resolves a wide QRS interval.

Psychotropic Pharmacotherapy Associated With QT Prolongation Among Veterans With Posttraumatic Stress Disorder.

BACKGROUND: In 2012, the Food and Drug Administration issued Drug Safety Communications on several drugs associated with QT prolongation and fatal ventricular arrhythmias. Among these was citalopram, a selective serotonin reuptake inhibitor (SSRI) approved for depression and commonly used for posttraumatic stress disorder (PTSD). Evaluation of the risk for QT prolongation among other psychotropic drugs for individuals with PTSD remains limited. OBJECTIVE: Explore psychotropic drugs associated with QT prolongation among veterans with PTSD. METHODS: Patients in the Veterans Health Administration in 2006-2009 with PTSD and QT prolongation (176 cases) were matched 1:4 on age, gender, visit date and setting, and physical comorbidity. Classification trees assessed QT prolongation risk among prescribed medications (n=880). RESULTS: Receipt of any drug with known risk of QT prolongation varied by group (23% QT cases vs 15% control, p<0.01). Psychotropic medications conferring significant risks included ziprasidone (3% vs 1%, p=0.02) and buspirone (6% vs 2%, p=0.01). Increased risk was not observed for the SSRIs, citalopram and fluoxetine. Classification trees found that sotalol and amitriptyline carried greater risk among cardiac patients and methadone, especially if prescribed with quetiapine, among noncardiac patients. Per adjusted survival model, patients with QT prolongation were at increased risk for death (hazard ratio=1.60; 95% CI=1.04-2.44). CONCLUSIONS: Decision models are particularly advantageous when exploring nonlinear relationships or nonadditive interactions. These findings may potentially affect clinical decision-making concerning treatment for PTSD. For patients at higher risk of QT prolongation, antidepressants other than amitriptyline should be considered. Medications for comorbid conditions should also be closely monitored for heightened QT prolongation risk.

Retrograde venography and three-dimensional mapping of a great cardiac vein with separate drainage into the high right atrium in a patient with Wolf-Parkinson-White syndrome.

A 13-year-old boy presenting with palpitations was diagnosed with Wolf-Parkinson-White syndrome. We elected to bring him to the electrophysiology lab for evaluation of the accessory pathway and potential ablation. Structural assessment of the coronary sinus with electro-anatomical mapping and retrograde venography led to the discovery of a great cardiac vein having a separate insertion from the coronary sinus into the high right atrium. The accessory pathway was localized to the left lateral portion of the mitral annulus and treated successfully with radiofrequency ablation. Such venous anatomical variant has been seldom reported, and its association with an accessory pathway is described here for the first time. Its recognition can have important implications when performing procedures that require access into the coronary venous system.

First description of a double-wall balloon breach during cryoballoon ablation for atrial fibrillation.

BALLOON BREACH DURING CRYOABLATION: To date, this is the first published report of a double-wall breach while using the cryoballoon ablation catheter during the treatment of a patient with atrial fibrillation; however, there have been previous balloon breaches in both the second and third-generation cryoballoon ablation catheter usage. In this report, we describe the case of a double-wall balloon breach and the intraoperative care that was necessary to stabilize the patient. Additionally, we review other known cases of double-wall balloon breaches, and we examine the safety systems of the cryoballoon catheter that mitigate some of the potential patient complications.

Emerging role of digital technology and remote monitoring in the care of cardiac patients.

Current available mobile health technologies make possible earlier diagnosis and long-term monitoring of patients with cardiovascular diseases. Remote monitoring of patients with implantable devices and chronic diseases has resulted in better outcomes reducing health care costs and hospital admissions. New care models, which shift point of care to the outpatient setting and the patient's home, necessitate innovations in technology.

Detection of left atrial thrombus by intracardiac echocardiography in patients undergoing ablation of atrial fibrillation.

BACKGROUND: The role of intracardiac echocardiography (ICE) to detect thrombus within left atrium (LA) before atrial fibrillation (AF) ablation despite a recent transesophageal echocardiogram (TEE) is not well defined. We examined the prevalence of LA/left atrial appendage (LAA) thrombus using ICE immediately prior to AF ablation in patients in whom anticoagulation was not withheld. METHODS: We analyzed 122 consecutive patients (62.6 ± 10.8 years, 90 males, CHA(2)DS(2) -VASc score 2.4 ± 1.5, persistent AF 29.5 %) who underwent an ICE-guided AF ablation 1 day after a negative (n = 120) or inconclusive (n = 2) TEE for LA thrombus. LA was imaged with ICE from the right atrium, coronary sinus, and right ventricular inflow tract (RVIT). ICE and TEE images were compared for LAA area, thrombus, and spontaneous echo contrast (SEC). RESULTS: LAA was adequately visualized in 99 and 100 % of patients with TEE and ICE, respectively. RVIT was the best ICE view for LAA visualization. The LAA 2-D-area measured by TEE was 4.9 ± 0.5 vs. 5 ± 0.5 cm(2) by ICE (P = NS). ICE identified a thrombus in seven patients with a previous negative TEE, leading to cancellation of ablation. It ruled out a thrombus in two patients with an inconclusive TEE. Thrombi were found in the LAA (n = 4), atrial septum (n = 2), and left superior pulmonary vein (n = 1). SEC during TEE was more frequent in patients with thrombus on ICE than those without (85.7 vs. 17.4 %; p = 0.03; positive predictive value 23.1 %, negative predictive value 98.9 %). CONCLUSIONS: The results of our staged imaging approach suggest that ICE has a complimentary value in re-screening the LA/LAA for thrombus after a recent negative or equivocal TEE. The presence of SEC during TEE increases the probability of finding a thrombus with ICE, which could potentially be dislodged during catheter manipulation.

Determination of left atrium volume by fast anatomical mapping and intracardiac echocardiography. The contribution of respiratory gating.

BACKGROUND: The anatomical reconstruction of the left atrium (LA) and pulmonary veins with fast anatomical mapping (FAM) and intracardiac echocardiography (ICE) using the Carto 3 system (Biosense Webster, Inc) provides real-time guidance to catheter manipulation during ablation of atrial fibrillation (AF). The present study compared real-time LA volume reconstruction using FAM and ICE. In addition, the contribution of respiratory gating was assessed. METHODS: LA reconstruction was created using FAM and ICE in 60 consecutive patients (mean age 63 ± 9 years; 38 males) undergoing AF ablation. In the first 30 patients, FAM and ICE were performed without respiratory gating. In the last 30 patients, FAM and ICE were performed with respiratory gating. RESULTS: LA volumes determined by FAM were larger than those obtained with ICE in the absence of respiratory gating (n = 30; 129.5 ± 44 vs 110 ± 39.7 cm(3); p = 0.001). However, respiratory gating reduced LA volume determined with FAM by 17.7 ± 6.6% resulting in similar LA volumes to those obtained using ICE [n = 30; 100 ± 29.7 (61-154) vs 101.53 ± 40.1 (56-212) cm(3), p = 0.7, NS]. CONCLUSIONS: In the absence of respiratory gating, LA volumes determined by FAM are larger than those obtained with ICE. In contrast, with the addition of respiratory gating, both FAM and ICE provide similar real-time LA volumes.

Tricuspid valve incompetence following implantation of ventricular leads.

Most cardiovascular implantable electronic devices (CIEDs) require a ventricular lead to be placed across the tricuspid valve. Tricuspid regurgitation (TR) is an understudied clinical complication of right ventricular lead implantation and its clinical significance is unknown. We review the incidence, predictors, and current management of TR as a complication of ventricular lead implantation. Emerging technologies, including leadless pacing devices and subcutaneous systems, offer the benefit of little or none tricuspid valve disruption.

Surface 12 lead electrocardiogram recordings using smart phone technology.

IMPORTANCE: AliveCor ECG is an FDA approved ambulatory cardiac rhythm monitor that records a single channel (lead I) ECG rhythm strip using an iPhone. In the past few years, the use of smartphones and tablets with health related applications has significantly proliferated. OBJECTIVE: In this initial feasibility trial, we attempted to reproduce the 12 lead ECG using the bipolar arrangement of the AliveCor monitor coupled to smart phone technology. METHODS: We used the AliveCor heart monitor coupled with an iPhone cellular phone and the AliveECG application (APP) in 5 individuals. RESULTS: In our 5 individuals, recordings from both a standard 12 lead ECG and the AliveCor generated 12 lead ECG had the same interpretation. CONCLUSIONS: This study demonstrates the feasibility of creating a 12 lead ECG with a smart phone. The validity of the recordings would seem to suggest that this technology could become an important useful tool for clinical use. This new hand held smart phone 12 lead ECG recorder needs further development and validation.

Clinical efficacy of dofetilide for the treatment of atrial tachyarrhythmias in adults with congenital heart disease.

BACKGROUND: Atrial tachyarrhythmias (AT) including atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia represent a clinical challenge in the adult with congenital heart disease (CHD). Dofetilide (D) is a rapidly activating delayed rectifier potassium channel (IKr) blocker effective in pharmacological conversion and maintenance of normal sinus rhythm in patients with AF and AFL. There is limited knowledge regarding the role of D in adults with CHD. METHODS: Safety and efficacy of D was evaluated in a consecutive group of thirteen adult patients (age 40 ± 11; six women) with CHD and refractory AT. RESULTS: Ten patients had persistent (four AFL, one AF, and five atrial tachycardia) and three paroxysmal (one AF and two atrial tachycardia) AT. All patients were symptomatic during tachycardia, 12 patients had previously failed 2 ± 1 antiarrhythmic drugs. Mean systemic ventricular ejection fraction was 55 ± 9%; baseline QRS complex duration was 129 ± 45 ms (>120 ms in six patients). Patients were followed on D for 33 ± 39 months (median 16). Among 10 patients with persistent AT, seven patients (70%) pharmacologically converted to sinus rhythm on D and three patients (30%) required direct current cardioversion. Two patients (15.4%) experienced complete arrhythmia suppression, and seven (53.8%) experienced significant clinical improvement with sporadic recurrences; average time to recurrence was 5.5 ± 3.5 months. One patient developed torsade de pointes during loading, and the drug was discontinued. D was discontinued in five (38.5%) other patients due to recurrence of AT (n = 4) and renal failure (n = 1). Corrected QT interval (QTc) increased from 452 ± 61 to 480 ± 49 ms (P = .04) and corrected JT interval (JTc) from 323 ± 39 to 341 ± 33 ms (P = .09). CONCLUSIONS: D should be considered a pharmacologic alternative when adult patients with CHD develop AT. D does not depress conduction, sinus node, or ventricular function but needs close monitoring for potential ventricular pro-arrhythmia.

Clinical significance of increased tricuspid valve incompetence following implantation of ventricular leads.

PURPOSE: Cardiac rhythm management devices (CRMD) require a ventricular lead to be placed across the tricuspid valve. Tricuspid regurgitation (TR) is an under-recognized clinical complication of lead implantation and its clinical significance is unknown. We studied the incidence of hospitalizations for congestive heart failure (CHF) exacerbation among patients with worsening TR after ventricular lead implantation. METHODS: We reviewed 148 patients (age 68 ± 15) that received a CRMD. TR and pulmonary artery systolic pressure (PASP) measured by Doppler echocardiography before and after CRMD implantation were analyzed. Hospitalizations for CHF exacerbation post-implantation were counted. RESULTS: Follow-up was 32 ± 14 months. Ninety-nine (67%) patients had no change, 24 (16%) slight, and 9 (6%) significant increase in TR after CRMD implantation, while 13 (9%) patients had slight and 3 (2%) significant improvement. Patients with a significant increase in TR had higher incidence of hospitalizations (1.7 ± 0.5) compared to patients with slight (0.8 ± 1; p = 0.006) or no increase (0.5 ± 1; p = 0.0002) in TR. Patients with significant increase in TR had a greater change in PASP (25 mmHg; p = 0.002) after device implantation compared to those with a slight (10 mmHg; p = 0.002) or no increase (0.7 mmHg; p = 0.17). CONCLUSION: Increased TR following CRMD implantation is relatively common (33%) and correlated with subsequent risk of hospitalization for heart failure. A preventive strategy and close monitoring for development or worsening of CHF after CRMD implantation may help prevent hospital admissions.