Age-Based Trends in the Outcomes of Percutaneous Left Atrial Appendage Occlusion: Insights from a Real-World Database.

The age-based trends in-hospital outcomes in patients with percutaneous left atrial appendage occlusion (LAAO) are unknown. Using the National Readmission Database from 2016 to 2019, patients who underwent LAAO were divided into 2 age groups: 60 to 79 and ≥80 years. The primary objective was to evaluate the age-based trends in the outcomes related to LAAO. The secondary objectives were to evaluate the mean cost and total cumulative cost of readmissions in both age groups in 2019. We identified 58,818 patients who underwent LAAO, of whom 36,964 (63%) were aged 60 to 79 years, and 21,854 (37%) were ≥80 years. The hospital mortality, pericardial complications, acute kidney injury, and in-hospital cardiac arrest did not change over time. The risk-adjusted postoperative stroke and bleeding requiring blood transfusion decreased in patients aged ≥80 years (p trend 0.03 for both outcomes). The length of stay decreased, and early discharge rates increased over time in both the unadjusted and risk-adjusted models in both age groups. The risk-adjusted 90-day readmission rates also decreased in patients aged ≥80 years. The inflation-adjusted cost did not change over time on the unadjusted and adjusted analyses. The total cumulative all-cause 90-readmission cost for both groups in 2019 was $31.7 million. Most outcomes after LAAO either improved or did not change from 2016 to 2019. Hospital mortality has remained <0.5% consistently since 2016. The risk-adjusted postoperative stroke, bleeding, and 90-day readmission rates improved in elderly vulnerable patients aged ≥80 years. The inflation-adjusted cost did not improve despite the decreasing length of stay and improving early discharge rates.

Risk of Atrial Fibrillation and Stroke After Bariatric Surgery in Patients With Morbid Obesity With or Without Obstructive Sleep Apnea.

Background and Purpose: Weight loss in morbidly obese patients reduces atrial fibrillation (AF); however, it is unknown whether similar benefits are maintained in patients with obstructive sleep apnea (OSA). We sought to determine whether incident AF and stroke rates are affected by OSA after weight loss and to identify predictors of AF and stroke. Methods: Differences in laparoscopic adjustable gastric banding­induced weight loss on incident AF and stroke events in those with and without OSA in the entire and in propensity-matched cohorts were determined longitudinally, and independent predictors of AF and stroke were identified. Results: Of 827 morbidly obese patients who underwent laparoscopic adjustable gastric banding (mean age, 44±11 years; mean body mass index, 49±8 kg/m2), incident AF was documented in 4.96% and stroke in 5.44% of patients during a mean 6.0±3.2-year follow-up. Despite a similar reduction in body weight (19.6% and 21% in 3 years), new-onset AF was significantly higher in patients with OSA than without OSA in the entire (1.7% versus 0.5% per year; P<0.001) and propensity-matched cohorts. Incident stroke was higher in the OSA than in the non-OSA group (2.10% versus 0.47% per year; P<0.001), but only 20% of patients with stroke had documented AF. On multivariate analysis, OSA (hazard ratio, 2.88 [95% CI, 1.45­5.73]), age, and hypertension were independent predictors of new-onset AF, and OSA (hazard ratio, 5.84 [95% CI, 3.02­11.30]), depression, and body mass index were for stroke events. Conclusions: In morbidly obese patients who underwent laparoscopic adjustable gastric banding, despite similar weight loss, patients with OSA had a higher incidence of AF and stroke than patients without OSA. Both non-AF and AF-related factors were involved in increasing stroke risk. Further investigation is warranted into whether OSA treatment helps reduce AF or stroke events in this population.

Characterizing Recurrence Following Hybrid Ablation in Patients With Persistent Atrial Fibrillation.

PURPOSE: It is widely accepted that atrial fibrillation (AF) accounts for half of arrhythmia recurrences following endocardial catheter ablation of AF. An epicardial-endocardial approach (hybrid) has emerged as an alternative to endocardial ablation alone for the treatment of AF, yet recurrence after a hybrid procedure has not been well characterized. This retrospective study is aimed at characterizing recurrence following hybrid ablation for patients with persistent AF. METHODS: Patients with persistent AF (N=108) received both endocardial and epicardial ablation of the posterior left atrial wall using catheter ablation and a small midline surgical approach (hybrid). Presence of atrial flutter or AF was determined with ambulatory monitoring (n=22) or electrocardiogram analysis (n=86) at each follow-up visit. Recurrence mode was confirmed by electrophysiology study for those patients undergoing subsequent catheter ablation after hybrid ablation. RESULTS: Patients were followed for a mean ± standard deviation of 25 ± 14 months. Of patients who had a recurrence, 53% (n=33) were in atrial flutter and 47% (n=29) were in AF. Of those who had a recurrence with atrial flutter, 14 received repeat ablation for either left (n=11) or left/right (n=3) atrial flutter and 3 received AF ablation. Half of ablations for atrial flutter recurrence following the hybrid procedure involved the mitral isthmus. CONCLUSIONS: Atrial flutter accounts for about half of arrhythmia recurrences post-hybrid ablation. If catheter ablation of the mitral isthmus is considered during the hybrid procedure to prevent subsequent occurrence of perimitral flutter, bidirectional block must be performed to ensure a complete line of block.

The beneficial effect of weight reduction on adverse cardiovascular outcomes following bariatric surgery is attenuated in patients with obstructive sleep apnea.

Weight loss after bariatric surgery is associated with reduction in adverse cardiovascular outcomes; however, the impact of obstructive sleep apnea (OSA) on reduction of cardiovascular outcomes after bariatric surgery in morbidly obese patients is not known. We retrospectively assessed differences in cardiovascular events after laparoscopic adjustable gastric banding (LAGB)-induced weight loss in patients with and without OSA before and after propensity score matching for age, sex, body mass index (BMI), and major comorbidities between the two groups and determined predictors of poor outcomes. OSA was present in 222 out of 830 patients (27 per cent) who underwent LAGB between 2001 and 2011. Despite a similar reduction in BMI (20.0 and 20.8 per cent), a significantly higher percentage of cardiovascular events were observed in patients with than without OSA (35.6 vs 6.9 per cent; p < 0.001) at 3 years (mean follow-up 6.0 ± 3.2; range: 0.5 to 13 years). The differences in the cumulative endpoint of new onset stroke, heart failure, myocardial infarction, venous thrombosis, and pulmonary embolism between the OSA and non-OSA groups were maintained after propensity matching. Patients with OSA treated with continuous positive airway pressure (CPAP) during sleep [n = 66] had lower cardiovascular event rates at 30 months compared with those not treated (p < 0.041). OSA (hazard ratio: 6.92, 95% CI: 3.39-14.13, p < 0.001) remained an independent predictor of cardiovascular events after multivariate analysis. Thus, patients with OSA, despite a similar initial weight loss after LAGB, had a higher incidence of cardiovascular events compared with a propensity-matched group without OSA. Treatment with CPAP appears to reduce such events.

Outcomes of In-Hospital Cardiopulmonary Resuscitation in Morbidly Obese Patients.

OBJECTIVES: This study sought to assess the impact of morbid obesity on outcomes in patients with in-hospital cardiac arrest (IHCA). BACKGROUND: Obesity is associated with increased risk of out-of-hospital cardiac arrest; however, little is known about survival of morbidly obese patients with IHCA. METHODS: Using the Nationwide Inpatient Sample database from 2001 to 2008, we identified adult patients undergoing resuscitation for IHCA, including those with morbid obesity (body mass index ≥40 kg/m2) by using International Classification of Diseases 9th edition codes and clinical outcomes. Outcomes including in-hospital mortality, length of stay, and discharge dispositions were identified. Logistic regression model was used to examine the independent association of morbid obesity with mortality. RESULTS: Of 1,293,071 IHCA cases, 27,469 cases (2.1%) were morbidly obese. The overall mortality was significantly higher for the morbidly obese group than for the nonobese group experiencing in-hospital non-ventricular fibrillation (non-VF) (77% vs. 73%, respectively; p = 0.006) or VF (65% vs. 58%, respectively; p = 0.01) arrest particularly if cardiac arrest happened late (>7 days) after hospitalization. Discharge to home was significantly lower in the morbidly obese group (21% vs. 31%, respectively; p = 0.04). After we adjusted for baseline variables, morbid obesity remained an independent predictor of increased mortality. Other independent predictors of mortality were age and severe sepsis for non-VF and VF group and venous thromboembolism, cirrhosis, stroke, malignancy, and rheumatologic conditions for non-VF group. CONCLUSIONS: The overall mortality of morbidly obese patients after IHCA is worse than that for nonobese patients, especially if IHCA occurs after 7 days of hospitalization and survivors are more likely to be transferred to a skilled nursing facility.

Comparative Effectiveness of Hybrid Ablation Versus Endocardial Catheter Ablation Alone in Patients With Persistent Atrial Fibrillation.

OBJECTIVES: The outcomes of hybrid ablation versus endocardial catheter ablation alone were evaluated in patients with persistent and long-standing persistent atrial fibrillation (AF). BACKGROUND: Variable outcomes exist following endocardial catheter ablation in medically refractory patients with persistent AF. A hybrid epicardial-endocardial approach has emerged as an alternative to endocardial ablation. METHODS: In 133 consecutive patients, 69 received endocardial ablation alone (pulmonary vein isolation and radiofrequency catheter ablation [endo group]) and 64 received endocardial catheter ablation and epicardial ablation (hybrid group). Recurrence was defined as any arrhythmia following the 3-month blanking period. RESULTS: Patients were followed for a median of 16 months. The hybrid and endo groups were similar in age (61 ± 10 years vs. 62 ± 8 years), body mass index (35 ± 6 kg/m2 vs. 35 ± 7 kg/m2), CHA2D2-VASc score (2 ± 1 vs. 2 ± 1), and ejection fraction (54 ± 11% vs. 53 ± 8%). The hybrid group had longer AF duration (median [interquartile range (IQR)] (12 months [IQR: 8 to 28 months] vs. 7 months [IQR: 5 to 12 months]; p < 0.001) and more previous ablations (58% vs. 25%; p < 0.001). Both groups had similar antiarrhythmic drug use at follow-up (55% vs. 48%). The hybrid group was less likely to have recurrence (37% vs. 58%; p = 0.013) and repeat ablation (9% vs. 26%; p = 0.012), and had an AF-free survival of 72% versus 51% (p = 0.01). CONCLUSIONS: Among patients with persistent AF, hybrid ablation is associated with less AF recurrence and fewer re-do ablations. Prospective large-scale randomized trials are needed to validate these results.

Identifying the third dimension in 2D fluoroscopy to create 3D cardiac maps.

Three-dimensional cardiac mapping is important for optimal visualization of the heart during cardiac ablation for the treatment of certain arrhythmias. However, many hospitals and clinics worldwide cannot afford the high cost of the current mapping systems. We set out to determine if, using predefined algorithms, comparable 3D cardiac maps could be created by a new device that relies on data generated from single-plane fluoroscopy and patient recording and monitoring systems, without the need for costly equipment, infrastructure changes, or specialized catheters. The study included phantom and animal experiments to compare the prototype test device, Navik 3D, with the existing CARTO 3 System. The primary endpoint directly compared: (a) the 3D distance between the Navik 3D-simulated ablation location and the back-projected ground truth location of the pacing and mapping catheter electrode, and (b) the same distance for CARTO. The study's primary objective was considered met if the 95% confidence lower limit was greater than 0.75% for the Navik 3D-CARTO difference between the 2 distances, or less than or equal to 2 mm. Study results showed that the Navik 3D performance was equivalent to the CARTO system, and that accurate 3D cardiac maps can be created using data from equipment that already exists in all electrophysiology labs.

Selective downregulation of mitochondrial electron transport chain activity and increased oxidative stress in human atrial fibrillation.

Mitochondria are critical for maintaining normal cardiac function, and a deficit in mitochondrial energetics can lead to the development of the substrate that promotes atrial fibrillation (AF) and its progression. However, the link between mitochondrial dysfunction and AF in humans is still not fully defined. The aim of this study was to elucidate differences in the functional activity of mitochondrial oxidative phosphorylation (OXPHOS) complexes and oxidative stress in right atrial tissue from patients without (non-AF) and with AF (AF) who were undergoing open-heart surgery and were not significantly different for age, sex, major comorbidities, and medications. The overall functional activity of the electron transport chain (ETC), NADH:O2 oxidoreductase activity, was reduced by 30% in atrial tissue from AF compared with non-AF patients. This was predominantly due to a selective reduction in complex I (0.06 ± 0.007 vs. 0.09 ± 0.006 nmol·min(-1)·citrate synthase activity(-1), P = 0.02) and II (0.11 ± 0.012 vs. 0.16 ± 0.012 nmol·min(-1)·citrate synthase activity(-1), P = 0.003) functional activity in AF patients. Conversely, complex V activity was significantly increased in AF patients (0.21 ± 0.027 vs. 0.12 ± 0.01 nmol·min(-1)·citrate synthase activity(-1), P = 0.005). In addition, AF patients exhibited a higher oxidative stress with increased production of mitochondrial superoxide (73 ± 17 vs. 11 ± 2 arbitrary units, P = 0.03) and 4-hydroxynonenal level (77.64 ± 30.2 vs. 9.83 ± 2.83 ng·mg(-1) protein, P = 0.048). Our findings suggest that AF is associated with selective downregulation of ETC activity and increased oxidative stress that can contribute to the progression of the substrate for AF.

Preexcitation Syndromes.

The classic electrocardiogram in Wolff-Parkinson-White (WPW) syndrome is characterized by a short PR interval and prolonged QRS duration in the presence of sinus rhythm with initial slurring. The clinical syndrome associated with above electrocardiogram finding and the history of paroxysmal supraventricular tachycardia is referred to as Wolff-Parkinson-White syndrome. Various eponyms describing accessory or anomalous conduction pathways in addition to the normal pathway are collectively referred to as preexcitation syndromes. The latter form and associated eponyms are frequently used in literature despite controversy and disagreements over their actual anatomical existence and electrophysiological significance. This communication highlights inherent deficiencies in the knowledge that has existed since the use of such eponyms began. With the advent of curative ablation, initially surgical, and then catheter based, the knowledge gaps have been mostly filled with better delineation of the anatomic and electrophysiological properties of anomalous atrioventricular pathways. It seems reasonable, therefore, to revisit the clinical and electrophysiologic role of preexcitation syndromes in current practice.

Circulating Biomarkers Predictive of Postoperative Atrial Fibrillation.

Postoperative atrial fibrillation (PoAF), a common complication of cardiac surgery, contributes significantly to morbidity, mortality, and increasing healthcare costs. Despite advances in surgical and medical management, the overall incidence of PoAF has not changed significantly, partly because of the limited understanding of mechanisms underlying acute surgery-related factors, such as myocardial injury, inflammation, sympathetic activation, and oxidative stress, which play an important role in the initiation of PoAF, whereas a preexisting atrial substrate appears to be more important in the maintenance of this dysrhythmia. Thus, in a majority of patients, PoAF becomes a manifestation of an underlying arrhythmogenic substrate that is unmasked after acute surgical stress. As such, the ability to identify which patients have this proarrhythmic substrate and are, therefore, at high risk for developing AF postoperatively, is important for the improved selection for prophylactic interventions, closer monitoring for complications, and establishing the probability of AF in the long term. This review highlights the role of the underlying substrate in promoting PoAF, proposed mechanisms, and the potential role of serum biomarkers to identify patients at risk for PoAF.

Clinical application of WHF-MOGE(S) classification for hypertrophic cardiomyopathy.

BACKGROUND: Recently, a new MOGE(S) (Morphofunctional, Organ involvement, Genetics, Etiology of details of the genetic disease or underlying cause, and functional Status) genotype to phenotype nosology system for classification of cardiomyopathies was proposed, but its clinical use has not been described. OBJECTIVES: This study presents the comprehensive geno-phenotypic evaluation of hypertrophic cardiomyopathy (HCM) patients by employing the newly proposed World Heart Federation classification of cardiomyopathies - the MOGE(S) classification. METHODS: From January 2011 to March 2014, 254 patients were evaluated (190 probands and 64 family members). Of those, 181 were HCM phenotype-positive probands, and 54.7% were male patients. Mean maximal left ventricular thickness was 2.2 ± 0.6 cm, with >2.5 cm thickness seen in 21.5% of patients. Obstructive HCM was present in 66.3% of patients, with an average peak gradient of 57.1 ± 47.2. Detailed clinical, imaging, and follow-up data were analyzed. Gene testing was performed in 129 patients (67.9%), and they were categorized into gene-positive (MHOHGADEG+) and gene-negative (MHOHGADEG-) groups based on the MOGE(S) classification. RESULTS: MHOHGADEG+ patients were younger at time of diagnosis, more likely to be female, more likely to have ventricular tachycardia and a family history of HCM or sudden death, had lower peak gradients, and were more likely to have sudden death risk factors. CONCLUSIONS: In addition to employing genotype-to-phenotype nosology to describe HCM, we propose a modification to the current MOGE(S) classification for HCM based on the presence or absence of obstruction and location of hypertrophy within the morphology.

Implantable cardioverter defibrillators in diabetics: efficacy and safety in patients at risk of sudden cardiac death.

Diabetes mellitus is a major risk factor for arrhythmogenesis and is associated with a two-fold increase in all-cause mortality and a four-fold increase in cardiovascular mortality including sudden cardiac death when compared with nondiabetics. Implantable cardioverter defibrillators (ICD) have been shown to effectively reduce arrhythmic death and all-cause mortality in patients with severe myocardial dysfunction. With a high competing risk of nonarrhythmic cardiac and noncardiac death, survival benefit of ICD in patients with diabetes mellitus could be reduced, but the subanalysis of diabetic patients in randomized clinical trials provides reassurance regarding a similar beneficial survival effect of ICD and cardiac resynchronization therapy in diabetics, as observed in the overall population with advanced heart disease. In this article, the authors highlight some of the clinical issues related to diabetes, summarize the data on the efficacy of ICD in diabetics when compared with nondiabetics and discuss concerns related to ICD implantation in patients with diabetes.

Pharmacological strategies for prevention of postoperative atrial fibrillation.

Atrial fibrillation (AF) complicating cardiac surgery continues to be a major problem that increases the postoperative risk of stroke, myocardial infarction, heart failure and costs and can affect long-term survival. The incidence of AF after surgery has not significantly changed over the last two decades, despite improvement in medical and surgical techniques. The mechanism and pathophysiology underlying postoperative AF (PoAF) is incompletely understood and results from a combination of acute and chronic factors, superimposed on an underlying abnormal atrial substrate with increased interstitial fibrosis. Several anti-arrhythmic and non-anti-arrhythmic medications have been used for the prevention of PoAF, but the effectiveness of these strategies has been limited due to a poor understanding of the basis for the increased susceptibility of the atria to AF in the postoperative setting. In this review, we summarize the pathophysiology underlying the development of PoAF and evidence behind pharmacological approaches used for its prevention in the postoperative setting.

Utility of unipolar recordings for complex Wolff-Parkinson-White ablation.

Radiofrequency ablation has been shown to be a safe and effective treatment strategy for the management of symptomatic patients with Wolff-Parkinson-White syndrome. It is supported by a success rate of 95% and a recurrence rate of less than 5%. However, ablation of accessory pathways can be challenging at times. The causes for failure can be grouped into three categories - unusual location of the pathway, technical difficulties in delivering the ablation and localization error [1]. In this case report we are reporting a case of a young male who presented to us with symptomatic Wolff-Parkinson-White syndrome with two failed prior ablations at another institution. This case illustrates the importance of knowing accurate localization and course of the accessory pathway by utilizing the unipolar and bipolar electrograms simultaneously during radiofrequency ablation.

Cardiac resynchronization therapy in patients with challenging anatomy due to venous anomalies or adult congenital heart disease.

BACKGROUND: Cardiac resynchronization therapy (CRT) has proven salutary effects in patients with congestive heart failure, systolic dysfunction, and electromechanical dyssynchrony in the setting of ischemic, nonischemic, and congenital cardiomyopathy. While CRT device implants have become routine in the adult ischemic or nonischemic cardiomyopathy populations, patients with congenital heart disease offer special challenges due to unusual anatomic variations. METHODS: A comprehensive assessment of anatomic abnormalities is essential prior to implant. In addition, implant techniques and equipment must be tailored to the expected anatomy. A flexible approach is necessary-implant may require equipment and techniques adapted from vascular intervention. CONCLUSION: This article describes our approach to CRT implant in patients with congenital heart disease, and is illustrated by reports of several cases.

Left atrial laceration with epicardial ligation device.

Many new devices and techniques are being developed to attempt a reduction in embolic stroke risk for patients with atrial fibrillation who are either unable or unwilling to maintain long-term anticoagulation. One of these new devices (LARIAT®, SentreHEART Inc., Redwood City, California, USA) employs delivery of an epicardial suture to ligate the left atrial appendage after percutaneous pericardial and transseptal access. This series presents three clinical cases that demonstrate a serious and recurrent complication of left atrial laceration and cardiac tamponade shortly following delivery of an epicardial suture ligation to the left atrial appendage. Three clinical cases are described in detail with pre- and postprocedure angiography and echocardiography as well as illustrations reflecting the surgeon's findings on direct visualization of the left atrial lacerations postligation. Potential hypotheses of each injury are examined in light of the case timelines and findings at sternotomy. There was no suggestion that tamponade was related to pericardial or transseptal access, but rather a complication with device delivery. These three patients quickly progressed to clinical cardiac tamponade despite attempted drainage, stressing the importance of cardiovascular surgery backup, including a cardiopulmonary bypass pump, when delivering novel, percutaneous ligation devices for the left atrial appendage.

Polymorphic ventricular tachycardia--part II: the channelopathies.

In this article, we explore the clinical and cellular phenomena of primary electrical diseases of the heart, that is, conditions purely related to ion channel dysfunction and not structural heart disease or reversible acquired causes. This growing classification of conditions, once considered together as "idiopathic ventricular fibrillation," continues to evolve and segregate into diseases that are phenotypically, molecularly, and genetically unique.