Hidden in Plain Sight-An Unusual Case of Acute-onset Persistent Dyspnea.

Pacemaker (PM) syndrome is an uncommon complication after PM or defibrillator implant in patients with long-standing persistent atrial fibrillation. We present a case where an unexpected and unrecognized improvement in a comorbid condition paradoxically led to worsened symptoms, ie, acute-onset persistent dyspnea, in a patient with a single-chamber implantable cardiac defibrillator. A careful review of clinical data led to diagnosis and successful treatment.

How to Perform a Completely Fluoroless Ablation.

Radiation exposure related to electrophysiology catheter ablation procedures carries small but non-negligible stochastic and deterministic effects on health. Lead aprons can also place considerable pressure on the spinal column, resulting in potentially detrimental consequences. Fortunately, however, advancements in tools used for arrhythmia mapping and ablation have made it feasible to reduce or essentially eliminate the need for fluoroscopy, with no impact on the efficacy or safety of such procedures, as demonstrated by several long-term outcome studies. In this review, we describe our stepwise approach to safely and efficiently perform a completely fluoroless ablation.

Wearable Devices for Remote Monitoring of Heart Rate and Heart Rate Variability-What We Know and What Is Coming.

Heart rate at rest and exercise may predict cardiovascular risk. Heart rate variability is a measure of variation in time between each heartbeat, representing the balance between the parasympathetic and sympathetic nervous system and may predict adverse cardiovascular events. With advances in technology and increasing commercial interest, the scope of remote monitoring health systems has expanded. In this review, we discuss the concepts behind cardiac signal generation and recording, wearable devices, pros and cons focusing on accuracy, ease of application of commercial and medical grade diagnostic devices, which showed promising results in terms of reliability and value. Incorporation of artificial intelligence and cloud based remote monitoring have been evolving to facilitate timely data processing, improve patient convenience and ensure data security.

Left Atrial Appendage Closure in a Patient With a Patent Foramen Ovale Septal Occluder Device.

Left atrial appendage closure (LAAC) has evolved as a safe alternative to oral anticoagulation therapy for stroke prophylaxis. However, the presence of a patent foramen ovale (PFO) occluder device is considered a relative contraindication. Here we report a successful case of LAAC in the presence of a PFO occluder device. (Level of Difficulty: Beginner.).

Spontaneous Pothole Cardioversion of a Wide Complex Tachycardia.

External mechanical forces, if properly timed and of sufficient energy, have rarely been reported to convert tachyarrhythmias to sinus rhythm. We report a case of a patient with a wide-complex tachycardia that spontaneously converted to sinus rhythm after an ambulance ran over a pothole during emergency transport to the hospital. (Level of Difficulty: Beginner.).

Causes and Predictors of 30-Day Readmission in Patients With Syncope/Collapse: A Nationwide Cohort Study.

Background Syncope accounts for 0.6% to 1.5% of hospitalizations in the United States. We sought to determine the causes and predictors of 30-day readmission in patients with syncope. Methods and Results We identified 323 250 encounters with a primary diagnosis of syncope/collapse in the 2013-2014 Nationwide Readmissions Database. We excluded patients younger than 18 years, those discharged in December, those who died during hospitalization, hospital transfers, and those whose length of stay was missing. We used multivariable logistic regression analysis to evaluate the association between baseline characteristics and 30-day readmission. A total of 282 311 syncope admissions were included. The median age was 72 years (interquartile range, 58-83), 53.9% were women, and 9.3% had 30-day readmission. The most common cause of 30-day readmissions was syncope/collapse, followed by cardiac, neurological, and infectious causes. Characteristics associated with 30-day readmissions were age 65 years and older (odds ratio [OR], 0.7; 95% confidence interval [ CI ], 0.6-0.7), female sex (OR, 0.9; 95% CI, 0.8-0.9), congestive heart failure (OR, 1.5; 95% CI, 1.2-1.9), atrial fibrillation/flutter (OR, 1.3; 95% CI, 1.3-1.4), diabetes mellitus (OR, 1.2; 95% CI, 1.2-1.3), coronary artery disease (OR, 1.2; 95% CI, 1.2-1.3), anemia (OR, 1.4; 95% CI, 1.4-1.5), chronic obstructive pulmonary disease (OR, 1.4; 95% CI, 1.3-1.4), home with home healthcare disposition (OR, 1.5; 95% CI, 1.5-1.6), leaving against medical advice (OR, 1.7; 95% CI, 1.6-1.9), length of stay of 3 to 5 days (OR, 1.5; 95% CI, 1.4-1.6) or >5 days (OR, 2; 95% CI, 1.8-2), and having private insurance (OR, 0.6; 95% CI, 0.6-0.7). Conclusions The 30-day readmission rate after syncope/collapse was 9.3%. We identified causes and risk factors associated with readmission. Future prospective studies are needed to derive risk-stratification models to reduce the high burden of readmissions.

Meta-analysis of randomized controlled trials on atrial fibrillation ablation in patients with heart failure with reduced ejection fraction.

BACKGROUND: The role of catheter ablation (CA) is increasingly recognized as a reasonable therapeutic option in patients with atrial fibrillation (AF) and heart failure (HF). HYPOTHESIS: We aimed to compare CA to medical therapy in AF patients with HF with reduced ejection fraction (HFrEF). METHODS: We searched the literature for randomized clinical trials comparing CA to medical therapy in this population. RESULTS: Six trials with a total of 775 patients were included. AF was persistent in 95% of patients with a mean duration of 18.5 ± 23 months prior enrollment. The mean age was 62.2 ± 7.8 years, mostly males (83%) with mean left ventricular ejection fraction (LVEF) of 31.2 ± 6.7%. Compared to medical therapy, CA has significantly improved LVEF by 5.9% (Mean difference [MD] 5.93, confidence interval [CI] 3.59-8.27, P < 0.00001, I2 = 87%), quality of life, (MD -9.01, CI -15.56, -2.45, P = 0.007, I2 = 47%), and functional capacity (MD 25.82, CI 5.46-46.18, P = 0.01, I2 = 90%). CA has less HF hospital readmissions (odds ratio [OR] 0.5, CI 0.32-0.78, P = 0.002, I2 = 0%) and death from any cause (OR 0.46, CI 0.29-0.73, P = 0.0009, I2 = 0%). Freedom from AF during follow-up was higher in patients who had CA (OR 24.2, CI 6.94-84.41, P < 0.00001, I2 = 81%. CONCLUSION: CA was superior to medical therapy in patients with AF and HFrEF in terms of symptoms, hemodynamic response, and clinical outcomes by reducing AF burden. However, these findings are applicable to the very specific patients enrolled in these trials.

Meta-analysis of Risk of Ventricular Arrhythmias After Improvement in Left Ventricular Ejection Fraction During Follow-Up in Patients With Primary Prevention Implantable Cardioverter Defibrillators.

Implantable cardioverter defibrillators (ICDs) reduce the risk of sudden cardiac death in patients with impaired left ventricular ejection fraction (LVEF). However, there are limited data on the long-term benefit of ICD therapy in patients whose LVEF subsequently improves. We conducted a meta-analysis to evaluate the effect of LVEF improvement on ICD therapy during follow-up. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were calculated using random-effects modeling. Sixteen studies with 3,959 patients were included in our analysis. Study arms were defined by LVEF improvement at follow-up (improved LVEF [>35%]: 1,622; low LVEF [≤35%] 2,337). Mean age (64.8 vs 64.9 years, p = 0.97) was similar, whereas men were overrepresented in the persistent low LVEF group (79% vs 72%, p <0.001). Appropriate ICD therapy rate was 9.7% (improved LVEF) versus 21.8% (low LVEF) over a median follow-up period of 2.9 years. In the meta-analysis, improved LVEF group had significantly lower (3.3% vs 7.2% per year IRR 0.52; CI 0.38 to 0.70; p <0.001) appropriate ICD therapies which was uniformly seen across all subgroups (ICD-only studies: IRR 0.59; p = 0.004) (cardiac resynchronization therapy-defibrillator-only studies: IRR 0.31; p = 0.002) (super-responder studies [mean LVEF > 45%]: IRR 0.53; p = 0.002). Inappropriate ICD therapy rates were, however, similar in both groups (3.01% vs 2.56% per year IRR 0.76; CI 0.43 to 1.36; p = 0.35). All-cause mortality rates in our meta-analysis favored (3.63% vs 8.23% per year IRR 0.49; CI 0.35 to 0.69; p <0.001) the improved LVEF group. In conclusion, our meta-analysis demonstrates that an improvement in LVEF is associated with a significantly reduced risk of ventricular arrhythmia and mortality. However, inappropriate ICD therapy rates remain similar.

A 50-year-old man with incidental cardiac mass.

CLINICAL INTRODUCTION: A 50-year-old white male with a history of paroxysmal atrial fibrillation presented for transoesophageal echocardiogram prior to atrial fibrillation ablation. However, an echo lucent mass was noted (figure 1A). Colour Doppler and contrast administration showed no flow across the mass or the interatrial septum (see online supplementary videos 1 and 2). CT of the chest demonstrated a thin-walled, well-demarcated mass in the inferior border of the fossa ovalis protruding into the left atrium (figure 1B). QUESTION: Which of the following is the most likely diagnosis? Atrial myxomaBronchogenic cystCardiac angiosarcomaHydatid cyst.

Premature ventricular contraction-induced cardiomyopathy.

Premature ventricular contractions are of common occurrence in routine clinical practice. Though generally perceived as of benign consequence in healthy people in the absence of heart disease, their presence can be a harbinger of fatal ventricular tachyarrhythmia in individuals with structural heart disease. With some of the latest insights into the treatment of ventricular tachyarrhythmia, especially with the advent of catheter ablation, there has been renewed interest in premature ventricular contractions, not only as a predictor of arrhythmia, but also for their potential etiological association with cardiomyopathy.

Prolonged QTc interval and torsades de pointes induced by citalopram.

Citalopram is a selective serotonin reuptake inhibitor with a favorable cardiac-safety profile. Corrected QT interval (QTc) prolongation and cardiac arrhythmias have not been previously reported in association with citalopram use except in the presence of overdose, abnormal electrolyte values, or renal or liver failure. Herein, we report the case of a 40-year-old woman with mental depression who presented with a prolonged QTc interval and torsades de pointes after the initiation of citalopram at therapeutic doses. The QTc interval improved when citalopram therapy was discontinued. We recommend that clinicians investigate the family history for sudden deaths and perform baseline electrocardiography before prescribing citalopram. We also recommend routine electrocardiographic testing during citalopram therapy, and that patients with long QT syndrome avoid taking citalopram.

Use of the Impella microaxial blood pump for ablation of hemodynamically unstable ventricular tachycardia.

Ablation for ventricular tachycardia remains a challenge with suboptimal procedural success rates. One of the major causes of difficulty is precipitous hypotension when ventricular tachycardia is induced precluding even rapid mapping of the arrhythmia. We report the successful use of the Impella microcirculatory axial blood flow pump in 3 patients with hemodynamically unstable ventricular tachycardia that allowed successful completion of the procedure. In these 3 patients, there was no evidence of Impella-related valvular disturbance, iatrogenic ventricular arrhythmias, or interference with mapping and ablation catheter movement.

Statins as antiarrhythmics: a systematic review part I: effects on risk of atrial fibrillation.

BACKGROUND: Recent studies have demonstrated that statins may possess antiarrhythmic properties in addition to their lipid-lowering effects. METHODS: Studies which reported the association of statins with the incidence of atrial arrhythmias were identified through a systematic review of published literature. RESULTS: One randomized, placebo-controlled trial of 200 patients undergoing cardiac surgery showed that atorvastatin decreased the incidence of postoperative atrial fibrillation by 61%. Observational studies in patients with stable coronary disease, left ventricular dysfunction, or those undergoing cardiac or noncardiac surgery show that statin therapy is associated with an approximately 50% lower rate of atrial fibrillation. Two small randomized trials reported conflicting results: one showing that atorvastatin reduced the recurrence of AF after electrical cardioversion and the other finding that pravastatin did not. CONCLUSIONS: Published data suggests that statins may possess antiarrhythmic properties that reduce the propensity for atrial fibrillation. Most of this data is observational; more randomized, placebo-controlled trials are needed.

Statins as anti-arrhythmics: a systematic review part II: effects on risk of ventricular arrhythmias.

BACKGROUND: Recent studies have demonstrated that statins may possess anti-arrhythmic properties in addition to their lipid-lowering effects. METHODS: Studies which reported the association of statins with the incidence of ventricular arrhythmias were identified through a systematic review of the published literature. RESULTS: Statins have been associated with a significant reductions in ventricular arrhythmia in cardiomyopathy patients with an implantable cardioverter defibrillator, although randomized trials have not been completed. CONCLUSIONS: Published data suggests that statins may possess anti-arrhythmic properties that reduce the propensity for ventricular arrhythmias. Most of this data is observational; more randomized, placebo-controlled trials are needed.

The role of renin-angiotensin-aldosterone system-based therapy in diabetes prevention and cardiovascular and renal protection.

Hypertension increases the risk of type 2 diabetes mellitus (T2DM) and cardiovascular disease. In addition to lowering blood pressure, blockade of the renin-angiotensin-aldosterone system (RAAS) reduces the risk of new-onset T2DM and offers renal protection. Using a MEDLINE search, we identified multiple trials that reported the incidence of T2DM in patients taking inhibitors of RAAS. In this review, we will discuss the RAAS as a potential target in diabetes prevention and the mechanisms through which inhibitors of this system achieve such an important effect. We will also shed light on the beneficial cardiovascular and renal effects of RAAS blockade. Although multiple studies have demonstrated that inhibitors of RAAS, especially angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, can reduce the incidence of T2DM, randomized controlled studies are still needed to further elucidate their exact role in diabetes prevention.

Rapid bioprosthetic valve degeneration resulting in severe mitral stenosis.

A 61-year-old man presented 9 months after bioprosthetic mitral valve implantation with progressive exertional dyspnea. Transesophageal echocardiography revealed severe mitral stenosis with diffuse leaflet thickening but no calcification. Subsequent pathologic examination of the valve demonstrated infiltrating fibroconnective tissue and chronic inflammation. Careful echocardiographic follow-up of this valve type may be warranted, especially in patients with early recurrent symptoms.

Coronary artery disease prognosis and C-reactive protein levels improve in proportion to percent lowering of low-density lipoprotein.

This editorial outlines the data supporting aggressive lipid goals and options for treating low-density lipoprotein (LDL) cholesterol to a range of approximately 30 to 70 mg/dl. The physiologically normal cholesterol range is approximately 30 to 70 mg/dl for native hunter-gatherers, healthy human neonates, free-living primates, and virtually all wild mammals. Randomized statin trials in patients with recent acute coronary syndromes and stable coronary artery disease have demonstrated that cardiovascular events are reduced and cardiovascular survival optimized when LDL cholesterol is reduced to <70 mg/dl. Secondary prevention trials have shown a decrease in all-cause mortality in proportion to the magnitude of LDL cholesterol reduction. An original analysis of available data shows that the ability of a lipid-lowering therapy to reduce the C-reactive protein level is closely correlated with its efficacy in LDL cholesterol reduction. Randomized trial data have shown no relation between either percentage LDL cholesterol decrease or final LDL cholesterol level achieved and the risk for myopathy or hepatic transaminase elevations associated with statins. Therefore, intensive LDL cholesterol reduction to levels of 30 to 70 mg/dl should be pursued in subjects with or at high risk for coronary artery disease.

Effects of omega-3 fatty acids on resting heart rate, heart rate recovery after exercise, and heart rate variability in men with healed myocardial infarctions and depressed ejection fractions.

We explored possible mechanisms by which recommended intakes of omega-3 fatty acids may decrease the risk for sudden cardiac death in patients with documented coronary heart disease. The cardioprotective effects of omega-3 fatty acids have been documented in epidemiologic and randomized controlled trials. These fatty acids are presumed to decrease susceptibility to fatal arrhythmias, but whether this is mediated by classic risk factors or direct cardiac mechanisms is not known. Eighteen white men with a history of myocardial infarction and ejection fractions <40% were randomized to placebo or omega-3 fatty acids (585 mg of docosahexaenoic acid and 225 mg of eicosapentaenoic acid) for two 4-month periods in a crossover design. At the end of each period, heart rate (HR), HR variability, and rate of HR recovery after exercise were determined, as were effects on arterial compliance, blood pressure, cardiac function, and fasting serum levels of lipids and inflammatory markers. Omega-3 fatty acids decreased HR at rest from 73 +/- 13 to 68 +/- 13 beats/min (p <0.0001) and improved 1-minute HR recovery after exercise (-27 +/- 10 to -32 +/- 12 beats/min, p <0.01). HR variability in the high-frequency band increased (p <0.02), but no change was noted in overall HR variability. There were no significant effects on blood pressure, arterial compliance, lipids, or inflammatory markers. These changes are consistent with an increase in vagal activity and may in part explain the observed decrease in risk for sudden cardiac death seen with omega-3 fatty acid supplementation.