Pro-arrhythmic Effect of the Vein of Marshall Ethanol Ablation: A Case Report of Perimitral Flutter After Vein of Marshall Ethanol Ablation.

The ligament of Marshall is an embryological remnant of the left superior vena cava that contains neural tissues shown to be an arrhythmogenic source of atrial fibrillation (AF). Vein of Marshall (VOM) ethanol ablation is an ablation technique that can potentially treat AF by targeting the ligament of Marshall. We report a case of a patient who developed a pro-arrhythmic effect related to VOM ethanol ablation, which manifested as a perimitral flutter.

Marked QTc Reduction Immediately Following Direct Current Cardioversion of Atrial Fibrillation: Clinical Implications and Mechanisms.

BACKGROUND: The QTc in sinus rhythm (SR) following direct current cardioversion (DCCV) of atrial fibrillation (AF) is commonly used as a baseline QTc for patients who require initiation of antiarrhythmic drugs for rhythm control. Inaccurate baseline QTc may cause drug-induced torsades de pointes. OBJECTIVES: This study sought to assess time-dependent QTc changes following DCCV. METHODS: We prospectively assessed QTc changes with Bazett's QTc and Fridericia's QTc formulas in 65 patients following conversion of AF to SR. Among these 65 patients, 48 underwent DCCV and 17 spontaneously converted to SR. RESULTS: There was a large and statistically significant decrease in QTc in SR immediately following DCCV in 40 patients, which occurred with an abrupt reduction in heart rate postcardioversion. This finding excluded 8 patients with ventricular-paced QRS. The mean decrease from QTc in AF was 70.7 ± 37.2 milliseconds in the QTc interval for heart rate using Bazett's formula and 33.8 ± 17.9 milliseconds in the QTc interval for heart rate using Fridericia's formula at 1-minute post-DCCV. In 17 patients with spontaneous conversion from AF to SR, the QTc reduction was comparable to those in patients with DCCV. The QTc increased with time and reached a steady state at 5 minutes following conversion. Initiation of Class III drugs based on the "shortened" baseline QTc following DCCV was associated with drug-induced torsades de pointes. CONCLUSIONS: In patients with AF following conversion, regardless spontaneous or DCCV, the QTc shortened significantly with decreases in heart rate, likely via the mechanism of time-dependent rate adaption of ventricular repolarization. A steady-state QTc at 5-minutes following DCCV should be used as real baseline for guidance of pharmacotherapy in patients with AF.

Dual atrial rhythms: a case report of an unusual cause of pacemaker syndrome.

BACKGROUND: Atrial dissociation (AD) is described as the existence of two simultaneous electrically isolated atrial rhythms. Theoretically, detection of dual atrial rhythms with a sufficiently high rate by pacemaker can lead to automatic mode switching and associated pacemaker syndrome. Such a clinical observation has not been reported before in the literature. CASE SUMMARY: An 87-year-old female with Ebstein's anomaly status post-tricuspid valve annuloplasty and tricuspid valve replacement and a dual-chamber pacemaker presented with congestive heart failure 1 week after undergoing atrial lead revision. Interrogation of her dual-chamber pacemaker revealed two atrial rhythms: sinus or atrial-paced rhythm and electrically isolated atrial tachycardia (AT). Sensing of both atrial rhythms by the pacemaker led to automatic mode switching, which manifested as ventricular paced rhythm with retrograde P waves on electrocardiogram. Adjusting the atrial lead sensitivity to a level higher than the sensing amplitude of AT restored atrial paced and ventricular sensed rhythm, which resulted in resolution of heart failure symptoms. DISCUSSION: Regardless of the cause of AD, there must be electrical insulation between the two rhythms for their independent coexistence in the atria. Atrial dissociation can lead to pacemaker syndrome from automatic mode switching. If the sensing amplitude during sinus rhythm is significantly larger than that of AT, adjusting the atrial lead sensitivity would solve the issue, as in the present case. Otherwise, atrial lead revision, pharmacotherapy, or AT ablation should be considered.

Terminal QRS Distortion in ST Elevation Myocardial Infarction as a Prediction of Mortality: Systematic Review and Meta-Analysis.

BACKGROUND: Terminal QRS distortion reflects advanced stage and large myocardial infarction predisposing the heart to adverse outcomes. Recent studies suggest that terminal QRS distortion is associated with morbidity and mortality in ST elevation myocardial infarction (STEMI). However, a systematic review and meta-analysis of the literature have not been done. OBJECTIVE: We assessed the association between terminal QRS distortion in patients with STEMI and mortality by a systematic review of the literature and a meta-analysis. METHODS: We comprehensively searched the databases of MEDLINE and EMBASE from inception to September 2017. Included studies were published prospective or retrospective cohort studies that compared all-cause mortality in subjects with STEMI with QRS distortion versus those without QRS distortion. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate risk ratios and 95% confidence intervals. RESULTS: Fifteen studies from January 1993 to May 2015 were included in this meta-analysis involving 7,479 subjects with STEMI (2,906 QRS distortion and 4,573 non-QRS distortion). QRS distortion was associated with increased mortality (pooled risk ratio = 1.81, 95% confidence interval: 1.37-2.40, p < 0.000, I2 = 41.6%). Considering the introduction of clopidogrel in 2004, we performed subgroup analyses before and after 2004, and the associated with higher mortality was still present (before 2004, RR 1.75, 95% CI 1.08-2.82, p = 0.022, I2 = 66.1%; after 2004, RR 1.96, 95% CI 1.44-2.65, p < 0.001, I2 = 0%). CONCLUSIONS: Terminal QRS distortion increased all-cause mortality by 81%. Our study suggests that terminal QRS distortion is an important tool to assess the risk in patients with STEMI.

Anaemia and mortality in patients with transcatheter aortic valve replacement: a systematic review and meta-analysis.

Objective: This study was done to determine the relationship between pre-procedural anaemia and mortality post transcatheter aortic valve replacement (TAVR). Introduction: TAVR is now a treatment option for patients with severe aortic stenosis (AS) with high surgical risk. Anaemia is a common comorbidity in the TAVR population. Small studies have suggested that anaemia is associated with worse short-term and long-term mortality in patients who underwent TAVR. However, there are no meta-analyses to further assess this association. Method: Studies were systematically searched from electronic databases (EMBASE and MEDLINE). Inclusion criteria were adult population with aortic stenosis who underwent TAVR, and number of patients with pre-procedural anaemia reported. Outcomes were short-term mortality or long-term mortality. Pooled effect size was calculated with a random-effect model, weighted for the inverse of variance. Heterogeneity was assessed with I2. Results: Six studies were included in the final analysis. Of these, pooled analysis of four studies examining association between anaemia and 30-day mortality did not show a statistically significant relationship. A pooled analysis of four studies examining the association of anaemia and long-term mortality after TAVR showed pooled adjusted risk ratio (RR) of 1.43, 95% CI 1.22-1.67 with low heterogeneity (I2 = 33%). Subgroup analysis after exclusion of one smaller study showed that the association remained significant (RR 1.41, 95% CI 1.27-1.56) with decreased heterogeneity (I2 = 0%). Conclusion: This systematic review and meta-analysis found an association between pre-procedural anaemia and increased long-term but not short-term mortality after TAVR. Further study of the pathophysiology underlying this association is needed.

New-onset atrial fibrillation is associated with increased mortality in critically ill patients: a systematic review and meta-analysis.

INTRODUCTION: Atrial fibrillation (AF) is one of the most comorbid conditions in critically ill patients requiring intensive care unit (ICU). Multiple studies have suggested that there may be an association between new-onset AF and adverse outcome in critically ill patients. However, there are no meta-analyses to assess this association. METHODS: Studies were systematically searched from electronic databases. Studies that examined the relationship between new-onset AF and adverse outcomes including mortality and length of stay in ICU patients were included. Studies that included patients with prior AF were excluded. The pooled effect size was calculated with a random-effect model, weighted for the inverse of variance, to determine an association between new-onset AF and in-hospital mortality. Heterogeneity was assessed with I2. RESULTS: Twelve studies were included. Pooled analysis showed statistically significant difference rate of the hospital mortality between patients with and without new-onset AF (OR 2.70; 95% CI 2.43-3.00). Subgroup analysis of only patients with sepsis or septic shock showed a significant association between new-onset AF and in-hospital mortality (OR 2.32; 95% CI 1.88-2.87). No significant heterogeneity was observed (I2 = 0%) in both analyses. Pooled analysis of four studies also showed a significant association between new-onset AF and short-term mortality (OR 2.22; 95% CI 1.28-3.83) with moderate heterogeneity (I2 = 67%). CONCLUSIONS: New-onset AF is associated with worse outcome in critically ill patients. Further studies should be done to evaluate for causality and adjust for confounders.

Frequent premature atrial complexes as a predictor of atrial fibrillation: Systematic review and meta-analysis.

BACKGROUND: Frequent premature atrial complexes (PACs) are associated with higher morbidity and mortality. Recent studies suggest that frequent PACs are associated with new onset atrial fibrillation (AF). However, a systematic review and meta-analysis of the literature has not been done. We assessed the association between frequent PACs and new onset AF by a systematic review and a meta-analysis. METHODS: We comprehensively searched the databases of MEDLINE and EMBASE from inception to September 2017. Included studies were published cohort (prospective or retrospective) that compared new onset AF among patients with and without frequent PACs documented by Holter monitoring or 12-lead electrocardiogram. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate risk ratios and 95% confidence intervals. RESULTS: Twelve studies from 2009 to 2017 were included in this meta-analysis involving 109,689 subjects (9217frequent and 100,472 non-frequent PACs). Frequent PACs were associated with increased risk of new onset AF (pooled risk ratio = 2.76, 95% confidence interval: 2.05-3.73, p < 0.000, I2 = 90.6%). CONCLUSION: Frequent PACs are associated with up to three-fold increased risk of new onset AF. Our study suggests that frequent PACs in general population is an independent predictor of new onset AF.

Left ventricular thrombosis in acute anterior myocardial infarction: Evaluation of hospital mortality, thromboembolism, and bleeding.

BACKGROUND: Left ventricular thrombosis (LVT) is a well-known complication of acute myocardial infarction, most commonly seen in anterior wall ST-segment elevation myocardial infarction (STEMI). It is associated with systemic thromboembolism. HYPOTHESIS: Our aim was to evaluate the impact of LVT on in-hospital mortality, thromboembolism, and bleeding in patients with anterior STEMI. METHODS: Data was collected from the Nationwide Inpatient Sample where patients with a primary diagnosis of "Anterior STEMI" [ICD9-CM code 410.1] were included. Comparisons were made between patients with LVT [ICD9-CM code 429.79] vs those without using propensity score matching (PSM). RESULTS: From 2002 to 2014, there were 157 891 cases of anterior STEMI. Among these, 649 (0.4%) had LVT. Post-PSM, there was no difference in in-hospital mortality between the groups with LVT and without (7.3% vs 8.6%). Thromboembolic event rate was higher with LVT compared to those without LVT (7.3% vs 2.1%). There was no difference in bleeding events between patients with LVT and those without (2.9% vs 3.2%). The baseline average length of stay in the group with LVT was longer than the group without LVT (7.9 ± 6.7 days vs 5.1 ± 6.0 days). The average hospitalization-related costs were also significantly higher among patients with LVT compared to those without (95 598 USD vs 66 641 USD per stay) at baseline. CONCLUSION: Among patients hospitalized with anterior STEMI, presence of LVT is associated with increased thromboembolic events, average length of hospital stay and average cost of hospitalization. However, it is not associated with increased in-hospital mortality or bleeding events.

Nonbacterial thrombotic endocarditis in a patient with primary antiphospholipid syndrome.

Nonbacterial thrombotic endocarditis (NBTE) is described in patients with mucin-producing cancers and connective tissue disorders (usually SLE). We report NBTE in the setting of primary antiphospholipid antibody syndrome (APS). A 65-year-old female with APS was incidentally found to have thickened mitral leaflets on transthoracic echocardiogram with no signs of infection. Transesophageal echocardiogram (TEE) showed a mobile mitral mass (1.4 × 0.7 cm) and moderate mitral regurgitation. Differential diagnoses included bacterial endocarditis, NBTE, thrombus or tumor. Given the history of primary APS, the absence of fever and negative blood cultures, NBTE was considered. Low-molecular-weight heparin, hydroxychloroquine and corticosteroid were initiated. Repeat TEE in a week revealed shrinkage of the mass (0.6 × 0.7 cm), indicating an inflammatory nature. Lifelong anticoagulation is indicated regardless of embolism occurrence. Hydroxychloroquine and corticosteroids may have roles in the treatment. Determining and treating the underlying etiology is important.

Etiologies, predictors, and economic impact of readmission within 1 month among patients with takotsubo cardiomyopathy.

BACKGROUND: Limited data exist on readmission among patients with takotsubo cardiomyopathy (TC), a commonly reversible cause of heart failure. HYPOTHESIS: We sought to identify etiologies and predictors for readmission among TC patients. METHODS: We queried the National Readmissions Database for 2013-2014 to identify patients with primary admission for TC using ICD-9-CM code 429.83. Patients readmitted to hospital within 1 month after discharge were further evaluated to identify etiologies, predictors, and resultant economic burden of readmission. Additionally, we analyzed readmission for TC at 6 months. RESULTS: We studied 5997 patients admitted with TC, of whom 1.2% experienced in-hospital mortality. Median age was 67 years, with 91.5% being female. Among survivors, 10.3% were readmitted within 1 month; 25% of the initial 1-month readmissions occurred within 4 days, 50% within 10 days, and 75% within 20 days from discharge. The most common etiologies for readmission were cardiac (26%), respiratory (16%), and gastrointestinal (11%) causes. Heart failure was the most common cardiac etiology. Significant predictors of increased 1-month readmission included systemic thromboembolic events, length of stay ≥3 days, and underlying psychoses. Obesity and private insurance predicted lower 1-month readmission. The annual national cost impact for index admission and 1-month readmissions was ≈$112 million. Recurrent TC was seen among 1.9% of patients readmitted within 6 months. CONCLUSIONS: Though the overall rate of 1-month readmission following TC is low, associated economic burden from readmission is still significant. Patients are readmitted mostly for noncardiac causes. Readmission for another episode of TC within 6 months was uncommon.

High Right Ventricular Stroke Work Index Is Associated with Worse Kidney Function in Patients with Heart Failure with Preserved Ejection Fraction.

BACKGROUND: In patients with heart failure with preserved ejection fraction (HFpEF), worse kidney function is associated with worse overall cardiac mechanics. Right ventricular stroke work index (RVSWI) is a parameter of right ventricular function. The aim of our study was to determine the relationship between RVSWI and glomerular filtration rate (GFR) in patients with HFpEF. METHOD: This was a single-center cross-sectional study. HFpEF is defined as patients with documented heart failure with ejection fraction > 50% and pulmonary wedge pressure > 15 mm Hg from right heart catheterization. RVSWI (normal value 8-12 g/m/beat/m2) was calculated using the formula: RVSWI = 0.0136 × stroke volume index × (mean pulmonary artery pressure - mean right atrial pressure). Univariate and multivariate linear regression analysis was performed to study the correlation between RVSWI and GFR. RESULT: Ninety-one patients were included in the study. The patients were predominantly female (n = 64, 70%) and African American (n = 61, 67%). Mean age was 66 ± 12 years. Mean GFR was 59 ± 35 mL/min/1.73 m2. Mean RVSWI was 11 ± 6 g/m/beat/m2. Linear regression analysis showed that there was a significant independent inverse relationship between RVSWI and GFR (unstandardized coefficient = -1.3, p = 0.029). In the subgroup with combined post and precapillary pulmonary hypertension (Cpc-PH) the association remained significant (unstandardized coefficient = -1.74, 95% CI -3.37 to -0.11, p = 0.04). CONCLUSION: High right ventricular workload indicated by high RVSWI is associated with worse renal function in patients with Cpc-PH. Further prospective studies are needed to better understand this association.

Breaking your heart-A review on CPR-related injuries.

Cardiopulmonary resuscitation (CPR) has been shown to increase survival after cardiac arrest, but is associated with the risk of acquired injuries to the patient. While traumatic chest wall injuries are most common, other injuries include upper airway, pulmonary and intra-abdominal injuries. This review discusses the risk factors and prevalence of CPR-related injuries.