Neurogenic cardiac outcome in patients after acute ischemic stroke: The brain and heart connection.

BACKGROUND: Neurogenic cardiac impairment can occur after acute ischemic stroke (AIS), but the mapping of the neuroanatomic correlation of stroke-related myocardial injury remains uncertain. This study aims to identify the association between cardiac outcomes and middle cerebral artery (MCA) ischemic stroke, with or without insular cortex involvement, as well as the impact of new-onset atrial fibrillation (AF) after AIS on recurrent stroke. METHODS: Serial measurements of high sensitivity troponin T (TnT), brain natriuretic peptide (BNP), electrocardiography (ECG), echocardiogram, and cardiac monitoring were performed on 415 patients with imaging confirmed MCA stroke, with or without insular involvement. Patients with renal failure, recent cardiovascular events, or congestive heart failure were excluded. RESULTS: One hundred fifteen patients (28%) had left MCA infarcts with insular involvement, 122 (29%) had right MCA infarcts involving insular cortex, and 178 (43%) had no insular involvement. Patients with left MCA stroke with insular involvement tended to exhibit higher BNP and TnI, and transient cardiac dysfunction, which mimicked Takotsubo cardiomyopathy in 10 patients with left ventricular ejection fraction (LVEF) of 20-40%. Incidence of new-onset AF was higher in right MCA stroke involving insula (39%) than left MCA involving insula (4%). Nine out of fifty-three patients with new-onset AF were not on anticoagulant therapy due to various reasons; none of them experienced recurrent AF or stroke during up to a 3-year follow-up period. Statistically significant correlations between BNP or TnT elevation and left insular infarcts, as well as the incidence of AF and right insular infarcts, were revealed using linear regression analysis. CONCLUSIONS: The present study demonstrated that acute left MCA stroke with insular involvement could cause transient cardiac dysfunction and elevated cardiac enzymes without persistent negative outcomes in the setting of health baseline cardiac condition. The incidence of new-onset AF was significantly higher in patients with right MCA stroke involving the insula. There was no increased risk of recurrent ischemic stroke in nine patients with newly developed AF who were not on anticoagulant therapy, which indicated a need for further research on presumed neurogenic AF and its management.

Same-day discharge after cryoballoon ablation of atrial fibrillation: A multicenter experience.

BACKGROUND: It is common practice to observe patients during an overnight stay (ONS) following a catheter ablation procedure for the treatment of atrial fibrillation (AF). OBJECTIVES: To investigate the safety and economic impact of a same-day discharge (SDD) protocol after cryoballoon ablation for treatment of AF in high-volume, geographically diverse US hospitals. METHODS: We retrospectively reviewed 2374 consecutive patients (1119 SDD and 1180 ONS) who underwent cryoballoon ablation for AF at three US centers. Baseline characteristics, acute procedure-related complications, and longer-term evaluations of safety were recorded during routine clinical follow-up. The mean cost of an ONS was used in a one-way sensitivity analysis to evaluate yearly cost savings as a function of the percentage of SDD cases per year. RESULTS: The SDD and ONS cohorts were predominately male (69% vs. 67%; p = .3), but SDD patients were younger (64 ± 11 vs. 66 ± 10; p < .0001) with lower body mass index (30 ± 6 vs. 31 ± 61; p < .0001) and CHA2 DS2 -VASc scores (1.4 ± 1.0 vs. 2.2 ± 1.4; p < .0002). There was no difference between SDD and ONS in the 30-day total complication rate (n = 15 [1.26%] versus n = 24 [2.03%]; p = .136, respectively). The most common complication was hematoma in both the SDD (n = 8; 0.67%) and ONS (n = 11; 0.93%) cohorts. Sensitivity analysis demonstrated that when 50% of every 100 patients treated were discharged the same day, hospital cost savings ranged from $45 825 to $83 813 per year across US hospitals. CONCLUSIONS: SDD following cryoballoon ablation for AF appears to be safe and is associated with cost savings across different US hospitals.

Cardiac perforation and lead dislodgement after implantation of a MR-conditional pacing lead: a single-center experience.

OBJECTIVE: The purpose of our study was to determine if the rate of lead-related complications was increased with the Medtronic CapSureFix MRI™ SureScan™ 5086 MRI pacing lead (5086; Medtronic Inc., Minneapolis, MN, USA) compared to the previous generation of Medtronic CapSureFix Novus™ 5076 pacing lead (5076). BACKGROUND: The 5086 lead is a newly introduced active-fixation pacemaker lead designed to be used conditionally in a magnetic resonance (MR) scanner. This lead has specific design changes compared to the previous generation of 5076 pacing leads. METHODS: This study was a retrospective case control study of 65 consecutive patients implanted with two 5086 leads compared to 92 consecutive control patients implanted with two 5076 leads over a 14-month period at a high-volume tertiary care hospital. RESULTS: Pericarditis, pericardial effusion, cardiac tamponade, or death within 30 days of implant were seen in eight patients from the 5086 cohort and two from the 5076 cohort (odds ratio 6.3, 95% confidence interval 1.3-30.8, P = 0.02). Lead dislodgement occurred in four of the 5086 patients and in none of the 5076 patients (P < 0.03). CONCLUSIONS: In a high-volume center, the incidence of pericarditis, cardiac perforation, tamponade, death, and lead dislodgement was significantly higher with the MR-conditional Medtronic 5086 lead when compared to the previous generation Medtronic 5076 lead.

Multidisciplinary Approach to Patent Foramen Ovale Closure for Cryptogenic Stroke: Brain-Heart Board Experience.

Background and Objectives: Patent foramen ovale (PFO) is present in approximately 25% of adult population. The prevalence of PFO is high in patients with cryptogenic stroke suggesting paradoxical embolism. PFO closure in carefully selected patients is an effective secondary preventive strategy in these patients. We report predictors of management recommendations by the multidisciplinary Board and their impact on outcomes. Methods: Brain-Heart Board comprises vascular and interventional neurology and cardiology subspecialties (structural, electrophysiology, and cardiac imaging). Adult patients referred to the Board for consideration of PFO closure between October 2017 to March 2021 were included in this retrospective cohort analysis. Demographics, comorbid conditions, risk of paradoxical embolism (RoPE) score, event frequencies (transient ischemic attack [TIA] or stroke, intracranial hemorrhage [ICH], post-PFO closure cardiac arrhythmias), and modified Rankin Scale (mRS) at 1 year were compared between the groups (PFO closure vs medical management). Multivariable logistic regression was used to identify factors associated with management recommendation and chi-square tests to test differences in outcomes for patients according to management. Results: Two hundred seventy patients (229 stroke; 41 TIA) were discussed by the Board for PFO closure. 119 (44.0%) patients were recommended for PFO closure of which 117 (98.3%) had evidence of ischemic infarct on imaging. In univariate analysis, age was similar (50 ± 11.9 vs 52 ± 12.8, p = 0.17), but RoPE score was higher in closure as compared with the medical management group (6 [IQR 5-7] vs 5 [IQR 4-7], p < 0.05). In multivariable analysis, TIA as the index event was an independent predictor of Board recommendation against PFO closure (OR 0.05, 95% CI 0.01-0.19, p < 0.05). Event frequency was low in both cohorts (5.9% vs 4.8%, p > 0.05) and comprised cardiac arrhythmias (6 cases of atrial fibrillation and 1 ICH in closure group; 1 TIA and 1 recurrent stroke in medical management group). Excellent functional outcome (mRS 0-1) was similar in both cohorts (66.3% vs 70.7%, p > 0.05) at 1 year. Discussion: Multidisciplinary Brain-Heart Board provides a clinical practice model of collaborative care to ensure proper patient selection for PFO closure. TIA as the index event is associated with recommendation of medical management by the multidisciplinary Brain-Heart Board.

Ventricular late gadolinium enhancement by cardiac MRI as a predictor of atrial fibrillation in hypertrophic cardiomyopathy.

BACKGROUND: Atrial fibrillation (AF) increases stroke and mortality in patients with hypertrophic cardiomyopathy (HCM). Cardiac MRI (CMR) is increasingly used to detect late gadolinium enhancement (LGE) as a reliable indicator of left ventricular fibrosis, a potential predisposing factor of AF. Our research explored the correlation between left ventricular LGE and AF prevalence in HCM. METHODS: This retrospective study involved 351 HCM patients who underwent CMR. LGE percentages (0%, 1-5%, 6-14%, ≥15%) on CMR were compared with AF prevalence in HCM patients. Demographic, comorbidity, and imaging data were analyzed using appropriate univariate and multivariate analyses assessing for significant differences in AF prevalence. The predetermined significance level was p < 0.05. RESULTS: CMR demonstrated increased LGE in those with AF (p = 0.004). Increased LGE correlated with increased AF rates: 27.6% (0% LGE), 38.5% (1-5% LGE), 44.4% (6-14% LGE), and 54.7% (≥15% LGE) (p = 0.101, p = 0.043, p = 0.002, respectively, vs. 0% LGE). Adjusted for age, differences persisted and were most evident for LGE >15% (p = 0.001). Multivariate analysis, factoring age, gender, BMI, RVSP, and LVEF, supported LGE (odds ratio of 1.20, p = 0.036) and LAVI (odds ratio 1.05, 1.02-1.07, p < 0.001) as predictive markers for AF prevalence. CONCLUSIONS: Our study suggests a correlation between ventricular LGE and AF in patients with HCM. LGE exceeding 15% was associated with a significant increase in AF prevalence. These patients may require more frequent AF monitoring.

Four-year follow-up of outcomes of the hybrid epicardial-endocardial ablation: A single-center experience.

BACKGROUND: The CONVERGE trial demonstrated that hybrid epicardial and endocardial ablation was more effective than catheter ablation for the treatment of persistent atrial fibrillation (AF) at 1 year. Long-term real-world outcome data are scarce. OBJECTIVE: We described a single-center experience by evaluating the long-term effectiveness and safety of hybrid epicardial-endocardial ablation. METHODS: This is a retrospective single-center study. Patients were followed up to 4 years. The primary end point was the rate of AF recurrence up to 4 years postablation. Secondary end points included reduction in antiarrhythmic therapy use, the effect of the ligament of Marshall removal, epicardial posterior wall, 3-dimensional mapping during epicardial ablation, and left atrial appendage exclusion as adjunct intraoperative interventions for AF recurrence. RESULTS: Of the 170 patients, 86.5% had persistent AF and 13.5% had long-standing persistent AF. AF-free survival was 87.6% at 1 year, 76.9% at 2 years, 70.4% at 3 years, and 59.3% at 4 years. Antiarrhythmic drug use was 87.6% at baseline and reduced to 21%, 20.6%, 18%, and 14.1% at year 1, 2, 3, and 4, respectively (P < .01 for all). Three-dimensional epicardial mapping showed a significant reduction in combined recurrence from 42% to 25% over 4 years of follow-up (P = .023). Ligament of Marshall and left atrial appendage exclusion showed numerical reduction in AF recurrence from 35% to 26% (P = .49) and from 44% to 30% (P = .07). CONCLUSION: The hybrid convergent procedure reduces AF recurrence and the need for antiarrhythmic drugs and, while maintaining a good safety profile, for the treatment of persistent and long-standing persistent AF.

Optimizing Care of Patients With Right Bundle Branch Block Undergoing Transcatheter Aortic Valve Replacement.

OBJECTIVES: To evaluate the use of temporary-permanent pacemaker (TPP) in patients with right bundle branch block (RBBB) undergoing transcatheter aortic valve replacement (TAVR). We also sought to identify key predictors of permanent pacemaker (PPM) within 30 days of TAVR in this population. BACKGROUND: RBBB is a well-recognized risk factor for PPM post TAVR. TPP provides stable transient pacing and reduces the need for critical care beds. METHODS: This is a retrospective chart review of 371 patients who underwent TAVR at our institution. All patients with pre-existing RBBB had TPP placed prior to TAVR (n = 37). The primary outcome was the need for critical care beds. Multivariate logistic regression analysis was performed to identify predictors of PPM within 30 days of TAVR. RESULTS: 67 patients required PPM within 30 days of TAVR, and 56 implanted before discharge. 51% (19 out of 37) of TPP group required PPM before discharge compared to 11% (37 out of 334) of No TPP (p < 0.001), yet TPP group spent significantly fewer hours in a critical care bed (19 vs 28 h, p = 0.01). Length of membranous septum (LMS) <8.49 mm was the strongest independent predictor of PPM within 30 days of TAVR (RAUC of 0.80, Sensitivity 0.7 and Specificity 0.8) and 98% of patients with LMS < 7 mm required PPM within 30 days. CONCLUSION: TPP-TAVR is a well-defined multidisciplinary protocol that reduces the need for critical care beds in patients with pre-existing RBBB referred for TAVR. Additionally, LMS is the strongest predictor of PPM implantation in this population. CONDENSED ABSTRACT (100 WORDS): This study evaluated the use of temporary-permanent pacemakers (TPP) in patients with right bundle branch block (RBBB) undergoing transcatheter aortic valve replacement (TAVR). TPP-TAVR provided stable pacing allowing for early mobilization and reduced the need for critical care beds. Multivariate logistic regression analysis identified length of membranous septum (LMS) <8.49 mm in patients with RBBB as the strongest independent predictor of PPM need within 30 days of TAVR. 98% of patients with RBBB and LMS < 7 mm required PPM at 30 days regardless of other characteristics including valve type and size.

Accuracy of pulsatile photoplethysmography applications or handheld devices vs. 12-lead ECG for atrial fibrillation screening: a systematic review and meta-analysis.

BACKGROUND: The relative accuracy of pulsatile photoplethysmography applications (PPG) or handheld (HH) devices compared with the gold standard 12-lead electrocardiogram (ECG) for the diagnosis of atrial fibrillation is unknown. METHODS: Digital databases were searched to identify relevant articles. Raw data were pooled using a bivariate model to calculate diagnostic accuracy measures and estimate Hierarchical Summary Receiver Operating Characteristic (HSROC). RESULTS: A total of 10 articles comprising 4296 patients (mean age 68.9 years, with 56% males) were included in the analysis. Compared with EKG, the pooled sensitivity of PPG and HH devices in AF detection was 0.93 (95% CI 0.87-0.96; p < 0.05) and 0.87 (95% CI. 0.74-0.94; p < 0.05), respectively. The pooled specificity of PPG and HH devices in AF detection was 0.91 (95% CI 0.88-0.94; p < 0.05) and 0.96 (95% CI 0.90-0.98; p < 0.05), respectively. The diagnostic odds ratio was 129 and 144 for PPG and HH devices, respectively. Fagan's nomogram showed the probability of a patient having AF and normal rhythm on PPG or HH devices was 2-3%, while the post-test probability of having AF with an irregular R-R interval on PPG or HH devices was 73% and 82%, respectively. The scatter plot of positive and negative likelihood ratio showed high confirmation of AF and reliability of exclusion of absence of irregular R-R intervals (positive likelihood ratio > 10, and negative likelihood ratio < 0.1) on HH devices while PPG was used as confirmation only. CONCLUSIONS: The PPG or HH devices can serve as a reliable alternative for the detection of AF.

A cost comparison of atrial fibrillation monitoring strategies after embolic stroke of undetermined source.

Background: Detection of atrial fibrillation (AF) in patients with embolic stroke of undetermined source (ESUS) is challenging due to its paroxysmal nature. We sought to assess AF detection with an insertable cardiac monitor (ICM) and to perform cost analysis for various AF monitoring strategies post-ESUS We applied this cost analysis modeling to recently published Stroke AF and Per Diem trials. Methods: Retrospective chart review was performed in consecutive hospitalized patients with ESUS who had ICM placed prior to discharge. Utilizing rate of ICM-detected AF and Medicare average payments, we modeled 30-day per-patient diagnostic costs of Immediate ICM insertion prior to discharge versus using a wearable monitor followed by ICM in patients with ESUS, from Medicare and patient out-of-pocket perspectives. Similar modeling strategy and cost analysis was applied to the Stroke AF and Per Diem trials. Results: In 192 ESUS patients, AF detection increased with length of monitoring: 7.3 % at 14 days, 9.4 % at 30 days, and 17.2 % after a median ~ 6 months (189 days). Cost modeling predicted that immediate ICM leads to $3683-$4070 lower Medicare payments per-patient and $1425-$1503 lower patient out-of-pocket costs compared to Wearable-to-ICM strategies. Using similar modeling in the PER DIEM and STROKE AF trials, the additive costs of the 30-day ELR to ICM strategy ranged from $3786-$3946 from a payer perspective and $1472-$1503 from a patient out-of-pocket perspective. Conclusions: Use of ICM immediately after ESUS is cost-saving compared to Wearable-to-ICM strategies, due to the cost and low diagnostic yield of short-term wearable cardiac monitoring.

Left Atrial Volume Index Predicts Arrhythmia-Free Survival in Patients with Persistent Atrial Fibrillation Undergoing Cryoballoon Ablation.

BACKGROUND: Pulmonary vein isolation (PVI) using cryoballoon ablation (PVI-C) is increasingly performed as a first-line strategy for the treatment of patients with persistent atrial fibrillation (PersAF); however, follow-up data and predictors of procedural success are lacking. OBJECTIVE: To study the efficacy of PVI-C in patients with PersAF, focusing on predictors of procedural success. METHODS: By retrospective review, 148 consecutive patients with PersAF who underwent PVI-C were analyzed. The impact of several variables on outcome was evaluated in univariate and multivariate analyses and Cox proportional hazards regression models. RESULTS: After a mean follow-up of 19.2±10.9 months, 75 (50.7%) patients remained arrhythmia-free without the need for antiarrhythmic drug therapy. Patients with a normal left atrial volume index (LAVI) achieved a 71.0% arrhythmia-free survival. LAVI was the most powerful predictor of procedural success. CONCLUSIONS: Arrhythmia-free survival after PVI-C in select patients with PersAF are promising. Moreover, LAVI is a valuable measurement to help guide ablation strategy and predict outcome when using cryoballoon ablation.

Radiofrequency catheter ablation of chronic atrial fibrillation guided by complex electrograms.

BACKGROUND: Radiofrequency catheter ablation of atrial fibrillation (AF) guided by complex fractionated atrial electrograms has been reported to eliminate AF in a large proportion of patients. However, only a small number of patients with chronic AF have been included in previous studies. METHODS AND RESULTS: In 100 patients (mean age, 57+/-11 years) with chronic AF, radiofrequency ablation was performed to target complex fractionated atrial electrograms at the pulmonary vein ostial and antral areas, various regions of the left atrium, and the coronary sinus until AF terminated or all identified complex fractionated atrial electrograms were eliminated. Ablation sites consisted of > or = 1 pulmonary vein in 46% of patients; the left atrial septum, roof, or anterior wall in all; and the coronary sinus in 55%. During 14+/-7 months of follow-up after a single ablation procedure, 33% of patients were in sinus rhythm without antiarrhythmic drugs, 38% had AF, 17% had both AF and atrial flutter, 9% had persistent atrial flutter, and 3% had paroxysmal AF on antiarrhythmic drugs. A second ablation procedure was performed in 44% of patients. Pulmonary vein tachycardia was found in all patients in both previously targeted and nontargeted pulmonary veins. There were multiple macroreentrant circuits in the majority of patients with atrial flutter. At 13+/-7 months after the last ablation procedure, 57% of patients were in sinus rhythm without antiarrhythmic drugs, 32% had persistent AF, 6% had paroxysmal AF, and 5% had atrial flutter. CONCLUSIONS: Modest short-term efficacy is achievable with radiofrequency ablation of chronic AF guided by complex fractionated atrial electrograms, but only after a second ablation procedure in > 40% of patients. Rapid activity in the pulmonary veins and multiple macroreentrant circuits are common mechanisms of recurrent atrial arrhythmias.

Body mass index, obstructive sleep apnea, and outcomes of catheter ablation of atrial fibrillation.

BACKGROUND: Obesity and obstructive sleep apnea (OSA) are associated with atrial fibrillation (AF). The effects of a large body mass index (BMI) and OSA on the results of radiofrequency catheter ablation (RFA) of AF are unclear. OBJECTIVE: To evaluate the effect of BMI and OSA on the efficacy of RFA for AF. METHODS: RFA was performed in 324 consecutive patients (mean age = 57 +/- 11 years) with paroxysmal (234) or chronic (90) AF. OSA was diagnosed by polysomnography in 32 of 324 patients (10%) prior to ablation. Among the 324 patients, 18% had a normal BMI (<25 kg/m(2)), 39% were overweight (BMI >/= 25 kg/m(2) and <30 kg/m(2)), and 43% were obese (>or=30 kg/m(2)). RFA was performed to eliminate complex fractionated atrial electrograms (CFAE) in the pulmonary vein antrum and left atrium. RESULTS: At 7 +/- 4 months after a single ablation procedure, 63% of patients without OSA and 41% with OSA were free from recurrent AF without antiarrhythmic drug therapy (P = 0.02). Multivariate analysis including variables of age, gender, type and duration of AF, OSA, BMI, left atrial size, ejection fraction, and hypertension demonstrated that OSA was the strongest predictor of recurrent AF (OR = 3.04, 95% CI: 1.11-8.32, P = 0.03). There was no association between BMI and freedom from recurrent AF. A serious complication occurred in 3 of 324 patients, with no relationship to BMI. CONCLUSIONS: OSA is a predictor of recurrent AF after RFA independent of its association with BMI and left atrial size. Obesity does not appear to affect outcomes after radiofrequency catheter ablation of AF.

Inducibility of paroxysmal atrial fibrillation by isoproterenol and its relation to the mode of onset of atrial fibrillation.

BACKGROUND: Isoproterenol has been used to assess inducibility during catheter ablation for paroxysmal PAF. However, no studies have determined the sensitivity and specificity of isoproterenol for the induction of AF. It also is not clear whether isoproterenol is equally effective in inducing AF in the clinical subtypes of vagotonic, adrenergic, and random AF. OBJECTIVE: To determine the sensitivity and specificity of isoproterenol for the induction of atrial fibrillation (AF). METHODS: Isoproterenol was infused at 5, 10, 15, and 20 microg/min at 2-minute intervals or until AF was induced in 20 control subjects with no history of AF and in 80 patients with PAF. RESULTS: Among the 20 control subjects, AF was induced by isoproterenol in one patient (5%). Among the 80 patients with PAF, persistent AF was induced in 67 patients (84%, P < 0.001). Isoproterenol induced AF in 15 of 17 patients (88%) with vagotonic AF, 11 of 11 patients (100%) with adrenergic AF, and 41 of 52 patients (79%) with random episodes of AF (P = 0.2). The yield of AF was 11% (9/80) after 5 microg/min, 28% (22/80) after 10 microg/min, 51% (40/78) after 15 microg/min, and 88% (67/76) after 20 microg/min of isoproterenol (P < 0.01). Isoproterenol had to be discontinued in four patients (5%) before reaching the maximum dose due to reversible chest pain or systolic blood pressure <85 mmHg. CONCLUSIONS: Isoproterenol at infusion rates up to 20 microg/min has a high sensitivity (88%) and specificity (95%) for induction of AF in patients with PAF, regardless of whether the clinical subtype is vagotonic, adrenergic, or random.

Complex electrograms within the coronary sinus: time- and frequency-domain characteristics, effects of antral pulmonary vein isolation, and relationship to clinical outcome in patients with paroxysmal and persistent atrial fibrillation.

BACKGROUND: The mechanistic and clinical significance of complex fractionated atrial electrograms (CFAE) in the coronary sinus (CS) has been unclear. METHODS AND RESULTS: Antral pulmonary vein isolation (APVI) was performed in 77 patients with paroxysmal (32) or persistent AF (45). CS electrograms recorded for 60 seconds before and after APVI were analyzed in the time- and frequency-domains. Dominant frequency (DF), complexity index (CI: change in polarity of depolarization), and fractionation index (FI: change in direction of depolarization slope) were determined. Before APVI, there was no difference in DF, CI, or FI between paroxysmal and persistent AF. APVI resulted in a significant decrease in DF, CI, and FI in all patients. Baseline CI (43 +/- 13/s vs 54 +/- 14/s, P = 0.03) and FI (64 +/- 23/s vs 87 +/- 30/s, P = 0.02) were lower in patients with paroxysmal AF who had AF terminated by ablation than who did not. At 10 +/- 2 months, 69% of patients with paroxysmal AF and 49% of patients with persistent AF were free from AF after single ablation. Baseline CI was higher among patients with paroxysmal AF who had AF after APVI (56 +/- 20/s vs 44 +/- 10/s, P = 0.03). In patients with persistent AF, there was a larger decrease in DF after APVI among patients who remained free from AF (13 +/- 11% vs 7 +/- 9%, P < 0.05). CONCLUSIONS: Complexity of CS electrograms may reflect drivers of AF that perpetuate paroxysmal AF after APVI. In persistent AF, the extent to which APVI decreases DF in the CS correlates with efficacy, suggesting that DF identifies patients who may require additional ablation beyond APVI.

Prevalence and characteristics of continuous electrical activity in patients with paroxysmal and persistent atrial fibrillation.

BACKGROUND: Complex fractionated atrial electrograms (CFAEs) may play a role in the genesis of atrial fibrillation (AF). One type of CFAE is continuous electrical activity (CEA). The prevalence and characteristics of CEA in patients with paroxysmal and persistent AF are unclear. METHODS AND RESULTS: In 44 patients (age = 59 +/- 8 years) with paroxysmal (25) or persistent (19) AF, bipolar electrograms were systematically recorded for > or =5 seconds at 24 left atrial (LA) sites, including 8 antral sites, and 2 sites within the coronary sinus (CS). CEA was defined as continuous depolarization for >1 second with no isoelectric interval. CEA was recorded at the LA septum (79%), antrum (66%), posterior (68%) and anterior walls (67%), roof (66%), base of the LA appendage (61%), inferior wall (61%), posterior mitral annulus (48%), CS (41%), and in the LA appendage (14%). Antral CEA was equally prevalent in patients with paroxysmal (63%) and persistent AF (70%, P = 0.12). In patients with paroxysmal AF, the prevalence of CEA was similar among antral and nonantral LA sites, except for the LA appendage. However, in patients with persistent AF, CEA was more prevalent at the nonantral (80%) than antral sites (70%, P = 0.03). CEA at nonantral sites except the CS was more prevalent in persistent than in paroxysmal AF (80% vs 57%, P < 0.001). The mean duration of intermittent episodes of CEA was longer in persistent than in paroxysmal AF (P < 0.001). CONCLUSIONS: The higher prevalence and duration of CEA at nonantral sites in persistent than in paroxysmal AF is consistent with a greater contribution of LA reentrant mechanisms in persistent AF. However, the high prevalence of CEA at nonantral sites in paroxysmal atrial fibrillation (PAF) suggests that CEA alone is a nonspecific marker of appropriate target sites for ablation of AF. The characteristics of CEA that most accurately identify drivers of AF remain to be determined.

Relationship of frequent postinfarction premature ventricular complexes to the reentry circuit of scar-related ventricular tachycardia.

BACKGROUND: Postinfarction reentrant ventricular tachycardia (VT) is usually scar-related. However, the sites of origin of premature ventricular complexes (PVCs) in the setting of healed myocardial infarction have not been well characterized. OBJECTIVE: The purpose of this study was to determine the site of origin of frequent PVCs in postinfarction patients with VT and to determine the relationship to VT exit sites. METHODS: Mapping and catheter ablation were performed in 13 consecutive patients (12 men, mean age 62 +/- 8 years, mean ejection fraction 0.32 +/- 0.12) with prior myocardial infarction, sustained monomorphic VT, and >10 PVCs/h. The mean PVC burden was 12% +/- 11% on a 24-hour Holter monitor. Electroanatomical left ventricular voltage maps were constructed during sinus rhythm to identify scars. Endocardial activation maps of the PVCs were correlated with the voltage maps, and the most prevalent PVCs were ablated. The effect of PVC ablation on the inducibility of VT was determined. RESULTS: Seventeen sustained monomorphic VTs were reproducibly inducible. There were a total of 34 different PVC morphologies. The site of origin was identified for 18 of the 34 PVC morphologies in 12 of 13 patients. The 18 PVCs for which the site of origin could be identified accounted for 89% of the PVC burden in these patients. The site of PVC origin was in the infarct scar in 11 patients, the border zone in 1 patient, and unidentifiable in 1 patient. The site of PVC origin corresponded to the VT exit site for 14 of 17 reproducibly inducible VTs. The PVCs that were successfully mapped were ablated, and this rendered VT no longer inducible. CONCLUSION: Postinfarction PVCs usually arise from the infarct scar, and their site of origin often corresponds to the exit site of a reentrant VT. Therefore, catheter ablation of the PVCs often is associated with the loss of inducible VT.

Cardiac amyloidosis: The great masquerader.

Cardiac amyloidosis is an elusive condition that is notorious for mimicking various cardiovascular conditions that present with left ventricular hypertrophy (LVH). The hypertrophy in amyloidosis is typically diffuse; however, rare reports of echocardiographic resemblances with hypertrophic cardiomyopathy (HCM) exist, such as asymmetric septal hypertrophy and left ventricular outflow tract obstruction. Cardiac MRI can help differentiate amyloidosis from hypertrophic cardiomyopathy in unclear situations. This differentiation from HCM and other forms of cardiomyopathy has important treatment implications. Here we present the case of a 76-year-old man with cardiomyopathy who had echocardiographic features of asymmetric hypertrophic cardiomyopathy but was correctly diagnosed with amyloidosis with the help of cardiac MRI and ECG.

Hypertrophic cardiomyopathy with a large apical ventricular aneurysm and mural thrombus.

Hypertrophic cardiomyopathy (HCM) is characterized by increased left ventricular wall thickness in the absence of any other identifiable cause of thickness. It predisposes the patient to increased risk of sudden cardiac death (SCD) due to fatal arrhythmias. Approximately 2% of the HCM patients have left ventricular apical aneurysm. CMR imaging is better in identifying this apical aneurysm as compared to echocardiogram. This apical aneurysm, which can be akinetic or dyskinetic, increases the risk of disease-related adverse events as compared to general HCM. These adverse disease-related events include SCD, thromboembolism, and symptoms of heart failure. We report a rare case of hypertrophic cardiomyopathy in association with Williams-Beuren Syndrome. On CMR imaging, patient was found to have a large apical aneurysm and mid-ventricular obstruction with underlying thrombus. He was started on oral anticoagulation, and ICD was recommended.

Safety of anticoagulation with uninterrupted warfarin vs. interrupted dabigatran in patients requiring an implantable cardiac device.

BACKGROUND: The optimal strategy of peri-procedural anticoagulation in patients undergoing permanent cardiac device implantation is controversial. Our objective was to compare the major bleeding and thromboembolic complications in patients managed with uninterrupted warfarin (UW) vs. interrupted dabigatran (ID) during permanent pacemaker (PPM) or implantable cardioverter defibrillators (ICD) implantation. METHODS: A retrospective cohort study of all eligible patients from July 2011 through January 2012 was performed. UW was defined as patients who had maintained a therapeutic international normalized ratio (INR) on the day of the procedure. ID was defined as stopping dabigatran ≥12 hours prior to the procedure and then resuming after implantation. Major bleeding events included hemothorax, hemopericardium, intracranial hemorrhage, gastrointestinal bleed, epistaxis, or pocket hematoma requiring surgical intervention. Thromboembolic complications included stroke, transient ischemic attack, deep venous thrombosis, pulmonary embolism, or arterial embolism. RESULTS: Of the 133 patients (73.4±11.0 years; 91 males) in the study, 86 received UW and 47 received ID. One (1.2%) patient in the UW group sustained hemopericardium perioperatively and died. In comparison, the ID patients had no complications. As compared to the ID group, the UW group had a higher median CHADS2 score (2 vs. 3, P=0.04) and incidence of Grade 1 pocket hematoma (0% vs. 7%, P=0.09). Neither group developed any thromboembolic complications. CONCLUSIONS: Major bleeding rates were similar among UW and ID groups. Perioperative ID appears to be a safe anticoagulation strategy for patients undergoing PPM or ICD implantation.