Endocardial (Watchman) vs epicardial (Lariat) left atrial appendage exclusion devices: Understanding the differences in the location and type of leaks and their clinical implications.

BACKGROUND: Watchman and Lariat left atrial appendage (LAA) occlusion devices are associated with LAA leaks postdeployment. OBJECTIVE: The purpose of this study was to compare the incidence, characteristics, and clinical significance of these leaks. METHODS: We performed a multicenter prospective observational study of all patients who underwent LAA closure. Baseline, procedural, and imaging variables along with LAA occlusion rates at 30-90 days and 1-year postprocedure were compared. RESULTS: A total of 478 patients (219 with the Watchman device and 259 with the Lariat device) with successful implants were included. Patients in the Lariat group had a higher CHADS2 (congestive heart failure, hypertension, age >74 years, diabetes, stroke) score and a larger left atrium and LAA. A total of 79 patients (17%) had a detectable leak at 1 year. More patients in the Watchman group had a leak compared with those in the Lariat group (46 [21%] vs 33 [14%]; P = .019). All the leaks were eccentric (edge effect) in the Watchman group and concentric (gunny sack effect) in the Lariat group. The size of the leak was larger in the Watchman group than in the Lariat group (3.10 ± 1.5 mm vs 2.15 ± 1.3 mm; P = .001). The Watchman group had 1 device embolization requiring surgery and 2 pericardial effusions requiring pericardiocentesis. In the Lariat group, 4 patients had cardiac tamponade requiring urgent surgical repair. Three patients in each group had a cerebrovascular accident and were not associated with device leaks. CONCLUSION: The Lariat device is associated with a lower rate of leaks at 1 year as compared with the Watchman device, with no difference in rates of cerebrovascular accident. There was no correlation between the presence of residual leak and the occurrence of cerebrovascular accident.

Safety and effectiveness of compassionate use of LARIAT® device for epicardial ligation of anatomically complex left atrial appendages.

BACKGROUND: Percutaneous left atrial appendage (LAA) ligation using an epicardial suture system (LARIAT®, SentreHEART, Palo Alto, CA) has been used in patients with nonvalvular atrial fibrillation (AF) and contraindication to oral anticoagulation. However, complex LAA anatomy may preclude its use. We report the safety and effectiveness of compassionate use of first-generation LARIAT® device for epicardial ligation of large, complex left atrial appendages. METHODS: Between January 2010 and March 2013, 93 patients with AF, high CHADS2 score, and contraindication(s) for oral anticoagulation therapy were evaluated for LAA ligation. Complex anatomy detected by 3D cardiac computed tomography CT angiography led to preclusion of 25 patients (27%). Of these, nine patients who opted for epicardial LAA ligation on compassionate grounds were studied. RESULTS: Mean age was 68.1 ± 8.2 years, four females, all with large LAA width (>40 mm, 45-58 mm) and additional anatomic complexities such as bilobed (two), long C-shaped-like (two), goose neck-like (one), multilobed cauliflower-like (two), cactus-like (one), and chicken wing-like (one) LAA. LAA ligation with LARIAT® was successfully performed with surgical standby in all patients. Seven patients (78%) were safely treated percutaneously and only two patients required minimally invasive thoracotomy (one due to inability to release the epicardial snare from long C-shaped LAA and other due to preexisting adhesions precluding pericardial entry). There were no major complications. Repeat trans-esophageal echocardiography at 3 months showed no remnant flow and none had stroke off Coumadin at 19.3 ± 8.2 months of follow-up. CONCLUSIONS: Despite a high preclusion rate, percutaneous LAA ligation may be safely and effectively performed on compassionate grounds using the first-generation LARIAT® device with surgical standby in patients with large and complex LAA.

Cryoballoon pressure waveform change during balloon inflation is not a reliable predictor of adequate pulmonary vein occlusion.

BACKGROUND: Cryoballoon ablation of pulmonary veins (PVs) is widely used to treat atrial fibrillation (AF). Successful ablation requires occluding the PVs by cryoballoon. Angiography is a standard method of assessing PV occlusion. To decrease contrast doses and overcome potential contraindications (e.g., allergy to contrast, renal disease), alternative methods have been tested, including intracardiac echocardiography, transesophageal echocardiography-color flow Doppler, and distal cryoballoon pressure monitoring. OBJECTIVE: We evaluated pressure monitoring's accuracy in detecting PV occlusion during cryoballoon ablation. METHODS: We studied 72 PVs in 18 nonconsecutive patients (mean age 68 ± 8 years; 13 male) who underwent cryoballoon ablation for paroxysmal AF. In 67 PVs, we documented the point at which the recorded pressure waveform at the distal tip of the inflated cryoballoon transformed from a left atrial into a pulmonary arterial pressure waveform. PV occlusion was confirmed by concurrent PV angiography through the distal balloon channel. Occlusion was rated on a I­IV scale in which I indicated poor occlusion with major leakage and IV indicated complete occlusion without leakage. RESULTS: In 43 of 67 PVs (64%), the change in the pressure waveform from left atrial to pulmonary arterial was associated with complete PV occlusion (grade IV), confirmed by angiography. In the other 24 PVs, complete occlusion was achieved by further movement of the cryoballoon under intracardiac echocardiographic guidance and angiographic confirmation. All 67 PVs were electrically isolated with cryoballoon. CONCLUSIONS: The change in pressure waveforms at the distal tip of inflated cryoballoon is not a reliable predictor of complete PV occlusion during cryoballoon ablation.

Race/ethnicity and the incidence of new-onset atrial fibrillation after isolated coronary artery bypass surgery.

BACKGROUND: Atrial fibrillation (AF) is more prevalent in Caucasians than in persons of other racial/ethnic groups. OBJECTIVE: The purpose of this study was to examine the association between race/ethnicity and new-onset postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG). METHODS: Data from all patients with no history of AF who underwent isolated CABG at our institution from 2000 through 2008 were analyzed. Univariate analyses of preoperative and perioperative variables were performed to identify predictors of POAF. Multivariate stepwise logistic regression was performed to determine independence. Propensity-score matching was used to assess racial/ethnic differences in POAF risk. RESULTS: Of the 5,823 patients (mean age 72 ± 11 years; 75.5% male) included in the study, 3,966 (68%) were Caucasian (mean age 65 ± 10 years; 77.9% male). The incidence of POAF was 28.9% (1,683/5,823) overall; 32.4% (1,287/3,966) in Caucasians and 21.3% (396/1,857) in non-Caucasians. Multivariate logistic regression revealed that Caucasian race/ethnicity independently predicted POAF (odds ratio [OR] 1.8, 95% confidence interval [CI] 1.5-2.0; P <.0001). The propensity-matching analysis of 715 Caucasians and 715 non-Caucasians confirmed Caucasian race/ethnicity as an independent predictor of POAF (OR 1.7, 95% CI 1.3-2.2; P <.001). Other independent predictors were obesity (OR 1.4, 95% CI 1.0-2.0; P = .04), congestive heart failure (OR 1.8, 95% CI 1.3-2.6; P = .0002), and age 50-59 years (OR 3.7, 95% CI 1.7-8.3; P = .0006), with increasing risk for each additional increment of 10 years. CONCLUSION: Caucasians are at higher risk for POAF after isolated CABG than are persons of other races. Race probably is a surrogate for unrecognized variables such as genetic disparities among racial/ethnic groups.

Lobectomy for pulmonary vein occlusion secondary to radiofrequency ablation.

Pulmonary vein stenosis, a recognized complication of transcatheter radiofrequency ablation in the left atrium, is often asymptomatic. Significant stenosis is commonly treated with percutaneous balloon dilation with or without stenting. We encountered a case of complete pulmonary vein occlusion that caused lobar thrombosis, pleuritic pain, and persistent cough. Imaging studies revealed virtually no perfusion to the affected lobe. A lobectomy was performed, resolving the persistent cough and pain. Pulmonary vein occlusion should be suspected in patients who present with pulmonary symptoms after having undergone ablative procedures for atrial fibrillation. This condition may necessitate surgical intervention if interventions such as balloon dilation or stenting are not possible or are ineffective.

Tachycardia-mediated cardiomyopathy and the permanent form of junctional reciprocating tachycardia.

Permanent junctional reciprocating tachycardia, or atrioventricular reentrant tachycardia utilizing a slowly conducting posteroseptal accessory pathway, is a rare form of reentrant supraventricular tachycardia in children and adults. The characteristic features of this narrow complex tachycardia are a long RP interval and inverted P waves in the inferior leads. This form of accessory-pathway-mediated tachycardia, which is usually incessant, can lead to a tachycardia-induced cardiomyopathy and congestive heart failure if left untreated. Radiofrequency ablation of the accessory pathway in permanent junctional reciprocating tachycardia is the definitive treatment in these patients, and in many instances the effects of prolonged tachycardia on ventricular function are reversible after successful ablation. We present an illustrative case.

Migraine and vasodepressor syncope in a large family.

We evaluated a 47-year-old woman for recurrent migraine and syncope. The patient had 7 children (not examined by the authors), all of whom also experienced migraine and syncope. The patient's father, now deceased, had reportedly experienced migraine and episodes of feeling faint. All 5 of the patient's siblings reported migraine, and 4 of the 5 reported syncope. The case of our patient, which we discuss herein, suggests a genetic link between these 2 conditions, both of which include vascular dysregulation in their pathogenesis. To our knowledge, the medical literature contains no previous description of familial associations of combined migraine and syncope.

Risk factors for major complications due to delay in surgery in staged carotid stenting and coronary bypass graft surgery.

AIMS: To answer the question whether the delay in coronary artery bypass grafting (CABG) after carotid stenting (CAS) results in adverse events, we describe our experience with planned staged CAS followed by CABG. METHODS AND RESULTS: We retrospectively surveyed our hospital carotid stenting data base, to identify all patients who were scheduled to undergo staged carotid stenting followed by CABG. A total of 39 patients who underwent CAS were candidates for staged CABG but only 28 (71.7%) of them referred. In the interval between carotid stenting and CABG, 4 deaths occurred (14.2% of cases), all of them were in the first week after CAS and due to cardiac problems. Also, 2 patients (7.1%) had a minor stroke. Increased number of predictors of type C (most important was stenosis of 95%-99%), age > 75 or significant valvular heart disease were associated with increased rate of complications after CAS. CONCLUSION: Should carotid intervention be performed in the high risk group of patients with > 4 suggested predictors of type C (most importantly is stenosis of 95%-99%), valvular heart disease or age > 75, physicians should closely observe the patients (perhaps in the hospital) during the waiting period before CABG, particularly in the first week after carotid stenting.

Postoperative atrial fibrillation and mortality after coronary artery bypass surgery.

OBJECTIVES: We sought to determine if the occurrence of postoperative atrial fibrillation (AF) affects early or late mortality following coronary artery bypass surgery (CABG). BACKGROUND: Atrial fibrillation is the most common arrhythmia seen following CABG. METHODS: The Texas Heart Institute Cardiovascular Research Database was used to identify all patients that developed AF after isolated initial CABG from January 1993 to December 1999 (n = 994). This population was compared with patients who underwent CABG during the same period but did not develop AF (n = 5,481). In-hospital end points were adjusted using logistic regression models to account for baseline differences. Long-term survival was evaluated using a retrospective cohort design, where Cox proportional hazards methods were used to adjust for baseline differences, and with case-matched populations (n = 390, 195 per arm). RESULTS: Atrial fibrillation was diagnosed in 16% of the population. Postoperative AF was associated with greater in-hospital mortality (odds ratio [OR] 1.7, p = 0.0001), more strokes (OR 2.02, p = 0.001), prolonged hospital stays (14 vs. 10 days, p < 0.0001), and a reduced incidence of myocardial infarction (OR 0.62, p = 0.01). At four to five years, survival was worse in patients who developed postoperative AF (74% vs. 87%, p < 0.0001 in the retrospective cohort; 80% vs. 93%, p = 0.003 in the case-matched population). On multivariate analysis, postoperative AF was an independent predictor of long-term mortality (adjusted OR 1.5, p < 0.001 in the retrospective cohort; OR 3.4, p = 0.0018 in the case-matched population). CONCLUSIONS: The occurrence of AF following CABG identifies a subset of patients who have a reduced survival probability following CABG. The impact of various strategies, such as antiarrhythmics and warfarin, aimed at reducing AF and its complications deserves further study.

Heart rate variability and cardiovascular mortality.

The autonomic nervous system plays a major role in affecting the cardiac milieu and promoting malignant ventricular activity. The measurement of heart rate variability (HRV) is a noninvasive tool for assessing the status of the autonomic nervous system. A depressed HRV among post-myocardial infarction patients is a well-established risk factor for arrhythmic death. A reduced HRV has also been used to identify diabetic patients with autonomic neuropathy. This paper presents recent developments in the use of HRV, focusing on further refinement and validation of the use of both linear and nonlinear dynamics for sudden death prognostication, evaluation of the effect of specific pharmacologic agents on HRV, and assessment of HRV in health and in specific disease states that have been associated with an increased mortality risk.