Asymptomatic paroxysmal ventricular standstill in an elderly male following revascularization of multivessel coronary disease: A case report and literature review.

Ventricular standstill is a dangerous arrhythmia that requires prompt diagnosis and intervention, especially in patients with structural heart disease. Clinicians should recognize ventricular standstill as a complication of cardiac revascularization and be cognizant of asymptomatic cases necessitating intervention. Early evaluation to facilitate pacemaker implantation portends good outcomes in this patient subgroup.

Prediction of Recurrence of Atrial Fibrillation Post-ablation Based on Atrial Fibrosis Seen on Late Gadolinium Enhancement MRI: A Metaanalysis.

OBJECTIVES: This meta-analysis aims to investigate the recurrence of atrial fibrillation (AF) post-ablation based on the various stages of fibrosis seen in the late gadolinium enhancement magnetic resonance imaging (LGE-MRI). METHODS: Electronic databases were searched using specific terms and identified nine studies that met the inclusion criteria. A total of 1,787 patients underwent LGE-MRI to assess atrial fibrosis before catheter ablation for AF. We performed three analyses: first, we compared stage IV versus stage I (reference group). The second set examined the combined stages III and IV versus stages I and II (reference group). The third set compared stage IV versus combined stages I, II, and III. The metanalysis relied on a random-effects model to pool the odds ratios (OR) and 95% confidence intervals (CI) using the DerSimonian and Laird method. The data was analyzed using StatsDirect software in England. RESULTS: The study showed a higher rate of AF recurrence after ablation in stage IV atrial fibrosis than in stage I (OR, 9.54; 95% CI, 3.81 to 28.89; P<00001). Also, in patients with combined stages III & IV of atrial fibrosis, AF recurrence was significantly higher after ablation than in stages I & II groups (OR, 2.37; 95% CI, 1.61 to 3.50; P<00001). Similarly, compared to combined stages I, II, and III, patients with stage IV have higher odds of recurrence post-ablation (OR, 4.24; 95% CI, 2.39- 7.52, P < 0.001). CONCLUSION: This metanalysis demonstrates the strong association between left atrial fibrosis in LGE-MRI and AF post-ablation recurrence. The finding of this study will further assist clinicians in predicting the recurrence rate of AF based on the amount of fibrosis and tailor therapeutic decisions for further management.

Outcomes of catheter ablation versus antiarrhythmic therapy in patients with atrial fibrillation: a systematic review and meta-analysis.

BACKGROUND: Recent data have shown an advantage of rhythm control over rate control for the treatment of atrial fibrillation (AF). Nevertheless, the data regarding efficacy of catheter ablation (CA) compared with antiarrhythmic drugs (AADs) in patients with AF is lacking. Therefore, we sought to evaluate recurrence of arrhythmia, all-cause mortality, cardiovascular deaths, stroke/TIA, and all-cause readmissions of CA compared with AAD in patients with AF. METHODS: Systematically searched through PubMed, Google Scholar, EMBASE, and Cochrane for randomized control trials that compared CA and AAD in atrial fibrillation patients. Review Manager 5.4 and OpenMetaAnalyst were used to analyze the data. Data was pooled for the outcomes using random-effect models (DerSimonian and Laird) and reported as pooled odds ratio (OR). RESULTS: A total of 4822 patients were included. The CA group had 2417 patients while the AAD group included 2405 patients. Pooled data demonstrated that the CA arm had a statistically significant decrease in risk for recurrence of arrhythmia as compared to AAD (OR 0.25; [95% CI, 0.18-0.36]; p < 0.001). All-cause readmission was statistically significantly lower in CA as compared to AAD (OR 0.33; [95%CI, 0.17-0.63]; p < 0.001). For other secondary outcomes, there was no statistically significant difference between CA and AAD with regard to all-cause mortality (OR 0.75; [95% CI, 0.55-1.03]), cardiovascular death (OR 0.76; [95% CI, 0.22-2.54]), bleeding (OR 1.09, [95% CI 0.74, 1.61]), or stroke/TIA outcome (OR 0.90, [95% CI, 0.59-1.37]). CONCLUSIONS: In this study of pooled data from 16 RCTs, CA utilization for atrial fibrillation had improved freedom from arrhythmia as well as reduced all-cause readmission compared with AAD.

Loperamide-Induced Ventricular Tachycardia Storm.

Loperamide is an over-the-counter antilaxative medication with minor opioid properties. For this reason, it has recently become a drug of concern for the Food and Drug Administration due to its potential for abuse. In addition, further apprehension pertaining to its over-the-counter availability has developed due to the recent increase in reported cases of loperamide overdose or prolonged use leading to arrhythmias. We described a rare case of loperamide-induced ventricular tachycardia storm.

Takotsubo Cardiomyopathy and QTc Prolongation with Subsequent Improvement of QTc Interval and Resolution of Apical Ballooning: A Case Report.

Stress-induced cardiomyopathy, also known as Takotsubo cardiomyopathy (TTS), is characterized by transient regional systolic dysfunction. Furthermore, electrocardiogram (ECG) changes can vary as TTS evolves. We report a case of a 67-year-old woman who presented to the ER after cardiac arrest. She was found to have stress-induced cardiomyopathy with prolonged QTc interval. The patient developed torsades de pointes for which she required cardioversion, followed by improvement of QTc interval corresponding to resolution of echocardiographic evidence of apical ballooning.

Clinical outcomes of adjunctive posterior wall isolation in persistent atrial fibrillation: A meta-analysis.

BACKGROUND: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation but the recurrence rate remains relatively high in persistent patients with AF. Therefore, posterior wall isolation (PWI) in addition to PVI has been proposed to increase freedom from AF. OBJECTIVE: To evaluate the success of adjunctive PWI in persistent AF. METHODS: We searched electronic database using specific terms. The primary outcomes are recurrence rate of AF and recurrence of atrial arrhythmias. The secondary outcomes were atrial flutter/tachycardia (AFL/AT), procedure time, fluoroscopy time, and procedure related complications. Estimated risk ratios (RRs) and 95% confidence intervals (CIs) were evaluated. RESULTS: Six studies were included (1334 patients with persistent AF). Adjunctive PWI resulted in a significant reduction in the recurrence rate of AF compared with patients who had PVI only (19.8% vs 29.1%; RR, 0.64; 95% CI, 0.42-0.97; P < .04; I2 = 76%). There was a significant reduction in the recurrence rate of all atrial arrhythmia (30.8% vs 41.1%; RR, 0.75; 95% CI, 0.60-0.94; P < .01; I2 = 60%). Compared with PVI only, adjunctive PWI did not increase the rate of AFL or AT (11.6% vs 13.9%; RR, 0.85; 95% CI, 0.54-1.32; P < .46; I2 = 47%) or the rate of procedure related complications (4.6% vs 3.6%; RR, 1.25; 95% CI, 0.72-2.17; P < .44; I2 = 0%). CONCLUSION: In patients with persistent AF, adjunctive PWI was associated with decreased recurrence of AF and atrial arrhythmias compared with PVI alone without an increased risk of AFL or AT or procedure related complications.

The Ubiquitous Premature Ventricular Complex.

Premature ventricular complexes (PVCs) are one of the most commonly encountered arrhythmias and are ubiquitous in clinical practice, both in the outpatient and inpatient settings. They are often discovered incidentally in asymptomatic patients, however, can cause myriad symptoms acutely and chronically. Long thought to be completely benign, PVCs have been historically disregarded without pursuing any further evaluation. Newer data have revealed that a high burden of PVCs with specific characteristics can significantly increase a patient's risk of developing PVC-induced cardiomyopathy. The aim of this literature review is to provide further clarification on the identification of high-risk PVCs, subsequent workup, and the currently available treatment options. PVCs arise from an ectopic focus within the ventricles. Patients with PVCs can be either asymptomatic or have severe disabling symptoms. The diagnostic workup for PVCs includes electrocardiogram (ECG) and 24-h Holter monitor to assess the QRS morphology and its frequency. A transthoracic echocardiogram (TTE) is done to look for structural heart disease and cardiomyopathy. Management of PVCs should be focused on identifying and treating the underlying causes, such as electrolyte abnormalities, substance use, and underlying structural heart disease. Beta-blockers are first-line therapy for symptomatic PVCs. Nondihydropyridine calcium channel blockers, classic antiarrhythmic agents, and amiodarone can be considered as second-line agents. Patients who are unable to tolerate medical therapy should undergo catheter ablation of the PVC focus to prevent PVC-induced cardiomyopathy. PVCs are common in clinical practice, and it is vital to identify patients at higher risk for PVC-induced cardiomyopathy to facilitate early intervention. Patients with no evidence of structural heart disease and infrequent PVCs should be monitored closely, while those who are symptomatic should be treated medically. For those who have failed medical therapy, catheter ablation of the PVCs focus is recommended. Catheter ablation has been shown to reduce PVCs burden and improve left ventricular ejection fraction (LVEF) in those with PVC-induced cardiomyopathy.

Meta-Analysis Evaluating Outcomes of Surgical Left Atrial Appendage Occlusion During Cardiac Surgery.

Surgical left atrial appendage occlusion (S-LAAO) has become a common procedure performed in patients undergoing cardiac surgery; however, evidence to support this procedure remains inconclusive. This meta-analysis aims to assess the efficacy of S-LAAO in terms of ischemic stroke, postoperative atrial fibrillation, and all-cause mortality. A thorough literature review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We identified 10 relevant studies for our meta-analysis. It included 6,779 patients who underwent S-LAAO and 6,573 who did not undergo LAAO. In terms of ischemic stroke, the S-LAAO cohort had a lower events (pooled odds ratio [OR] 0.655 (0.518 to 0.829), p = 0.0004) compared with the non-LAAO cohort. S-LAAO cohort also had lower events of all-cause mortality (pooled OR 0.74 (95% confidence interval 0.55 to 0.99), p = 0.0408) when compared with the non-LAAO cohort. In regards to postoperative atrial fibrillation, there was no difference between the 2 groups (pooled OR 1.29 (95% confidence interval 0.81 to 2.06), p = 0.2752). In conclusion, S-LAAO was associated with lower events of ischemic stroke or systemic embolism and all-cause mortality when compared to the non-LAAO group.

Invasive treatment of atrial fibrillation.

PURPOSE OF REVIEW: The treatment of atrial fibrillation has experienced a significant evolution over the past two decades. Catheter-based ablation has become a first-line option in various guidelines. In this review, we highlight the recent multicenter ablation studies and the challenges facing this treatment modality. RECENT FINDINGS: Improved efficacy and safety of an invasive treatment of paroxysmal and persistent atrial fibrillation with catheter ablation. SUMMARY: Atrial fibrillation is a major health problem. Catheter ablation has become a standard of care in managing paroxysmal and persistent atrial fibrillation. This treatment modality, however, still faces major challenges, especially in patients presenting with persistent atrial fibrillation.

Prevalence and Impact of Chagas Disease Among Latin American Immigrants With Nonischemic Cardiomyopathy in Los Angeles, California.

BACKGROUND: Chagas disease is a well-known cause of cardiomyopathy in Latin America; however, 300 000 individuals are estimated to have Chagas disease in the United States. This study examined the prevalence and impact of Chagas cardiomyopathy (CCM) in a US population. We hypothesized that patients with CCM would have increased morbidity and mortality when compared with patients with non-CCM. METHODS AND RESULTS: This is a single-center, prospective cohort study. Enrollment criteria were new diagnosis of nonischemic cardiomyopathy (left ventricular ejection fraction ≤40%) and previous residence in Latin America for at least 12 months. Serological testing for Trypanosoma cruzi was performed at enrollment. The primary end point was all-cause mortality or heart transplantation. The secondary end point was heart failure-related hospitalization. A total of 135 patients were enrolled, with a median of 43 months of follow-up. Chagas disease was diagnosed in 25 (19%) patients. The primary end point occurred in 9 patients (36%) in the CCM group and in 11 patients (10%) in the non-CCM group (hazard ratio [HR], 4.46; 95% confidence interval, 1.8-10.8; P=0.001). The secondary end point occurred in 13 patients (52%) in the CCM group and in 35 patients (32%) in the non-CCM group (HR, 2.22; 95% confidence interval, 1.2-4.2; P=0.01). CONCLUSIONS: There is a high prevalence of Chagas disease among Latin American immigrants diagnosed with nonischemic cardiomyopathy in Los Angeles. Advanced CCM portends a poor prognosis and is associated with increased all-cause mortality/heart transplantation and heart failure-related hospitalization.

Pulsatility and the risk of nonsurgical bleeding in patients supported with the continuous-flow left ventricular assist device HeartMate II.

BACKGROUND: Bleeding is an important cause of morbidity and mortality in patients with continuous-flow left ventricular assist devices (LVADs). Reduced pulsatility has been implicated as a contributing cause. The aim of this study was to assess the effects of different degrees of pulsatility on the incidence of nonsurgical bleeding. METHODS AND RESULTS: The Utah Transplantation Affiliated Hospitals (U.T.A.H.) heart failure and transplant program databases were queried for patients with end-stage heart failure who required support with the continuous-flow LVAD HeartMate II (Thoratec Corp, Pleasanton, CA) between 2004 and 2012. Pulsatility was evaluated by means of the LVAD parameter pulsatility index (PI) and by the echocardiographic assessment of aortic valve opening during the first 3 months of LVAD support. PI was analyzed as a continuous variable and also stratified according to tertiles of all the PI measurements during the study period (low PI: <4.6, intermediate PI: 4.6-5.2, and high PI: >5.2). Major nonsurgical bleeding associated with a decrease in hemoglobin ≥2 g/dL (in the absence of hemolysis) was the primary end point. A total of 134 patients (median age of 60 [interquartile range: 49-68] years, 78% men) were included. Major bleeding occurred in 33 (25%) patients (70% gastrointestinal, 21% epistaxis, 3% genitourinary, and 6% intracranial). In multivariable analysis, PI examined either as a categorical variable, low versus high PI (hazard ratio, 4.06; 95% confidence interval, 1.35-12.21; P=0.04), or as a continuous variable (hazard ratio, 0.60; 95% confidence interval, 0.40-0.92; P=0.02) was associated with an increased risk of bleeding. CONCLUSIONS: Reduced pulsatility in patients supported with the continuous-flow LVAD HeartMate II is associated with an increased risk of nonsurgical bleeding, as evaluated by PI.

Electromagnetic interference of automatic implantable cardioverter defibrillator and HeartWare left ventricular assist device.

The use of continuous-flow left ventricular assist devices (LVAD) have markedly improved outcomes in patients with advanced heart failure (HF). The HeartWare LVAD is a miniaturized centrifugal pump implanted within the pericardial space. Implantable cardioverter-defibrillators (ICDs) are susceptible to oversensing of extracardiac signals (electromagnetic interference [EMI]). We report two cases of EMI in patients that received a HeartWare LVAD as destination therapy for advanced HF. The patients were 75 and 78 years old, both with severe ischemic dilated cardiomyopathy (ejection fraction < 0.20) and New York Heart Association class 4 heart failure. Both patients had a St. Jude Medical Unify ICD with a 7 Fr dual coil St. Jude Medical Durata ICD lead. In both patients, the lead location was in the right ventricular apex with an inferior orientation. Both patients experienced immediate ICD therapies after LVAD placement, requiring the tachytherapies to be disabled. ICD programming changes to increase sensitivity and the detection windows were ineffective. Both patients underwent ICD system revision. In one patient, the existing lead was moved to an anteroseptal location that stopped the EMI. In the other patient, the ICD system was changed to allow a separate right ventricular sensing lead in an anteroseptal location and a dual coil ICD lead placed in an apical location, a strategy used to obtain an acceptable defibrillation threshold. The patients have had no subsequent EMI detected on clinical and remote monitoring. Patients with a right ventricular apical ICD lead placement that undergo placement of a HeartWare LVAD are susceptible to EMI and inappropriate ICD therapies. These cases suggest the primary mechanism is proximity of the ICD lead to the device and as such relocation to an anteroseptal location can overcome the problem. These data suggest that all patients that receive a HeartWare LVAD with an ICD should have the device carefully checked at maximum LVAD output to determine if EMI may be present. ASAIO Journal 2013;59:136-139. Key Words: left ventricular assist device, electromagnetic interference, improper ICD shocks, end-stage heart failure.