Heat and cold stress increases the risk of paroxysmal supraventricular tachycardia.

Paroxysmal supraventricular tachycardia (PSVT) is a common arrhythmia in adults. Its occurrence depends on the presence of the reentry circuit and the trigger of the paroxysm. Stress, emotional factors, and comorbidities favour the occurrence of such an episode. We hypothesized that the occurrence of PSVT follows extreme thermal episodes. The retrospective analysis was based on the data collected from three hospital emergency departments in Poland (Olsztyn, Radom, and Wroclaw) involving 816 admissions for PSVT in the period of 2016-2021. To test the hypothesis, we applied the Universal Climate Thermal Index (UTCI) to objectively determine exposure to cold or heat stress. The risk (RR) for PSVT increased to 1.37 (p = 0.006) in cold stress and 1.24 (p = 0.05) in heat stress when compared to thermoneutral conditions. The likelihood of PSVT during cold/heat stress is higher in women (RR = 1.59, p< 0.001 and RR = 1.36, p = 0.024, respectively) than in men (RR = 0.64 at p = 0.088 and RR = 0.78, p = 0.083, respectively). The susceptibility for PSVT was even higher in all groups of women after exclusion of perimenopausal group of women, in thermal stress (RR = 1.74, p< 0.001, RR = 1.56, p = 0.029, respectively). Females, particularly at the perimenopausal stage and men irrespective of age were less likely to develop PSVT under thermal stress as compared to thermoneutral conditions. Progress in climate change requires searching for universal methods and tools to monitor relationships between humans and climate. Our paper confirms that the UTCI is the universal tool describing the impact of thermal stress on the human body and its high usefulness in medical researches.

Natural History of Arrhythmia After Successful Isolation of Pulmonary Veins, Left Atrial Posterior Wall, and Superior Vena Cava in Patients With Paroxysmal Atrial Fibrillation: A Multi-Center Experience.

Background We evaluated long-term outcome of isolation of pulmonary veins, left atrial posterior wall, and superior vena cava, including time to recurrence and prevalent triggering foci at repeat ablation in patients with paroxysmal atrial fibrillation with or without cardiovascular comorbidities. Methods and Results A total of 1633 consecutive patients with paroxysmal atrial fibrillation that were arrhythmia-free for 2 years following the index ablation were classified into: group 1 (without comorbidities); n=692 and group 2 (with comorbidities); n=941. We excluded patients with documented ablation of areas other than pulmonary veins, the left atrial posterior wall, and the superior vena cava at the index procedure. At 10 years after an average of 1.2 procedures, 215 (31%) and 480 (51%) patients had recurrence with median time to recurrence being 7.4 (interquartile interval [IQI] 4.3-8.5) and 5.6 (IQI 3.8-8.3) years in group 1 and 2, respectively. A total of 201 (93.5%) and 456 (95%) patients from group 1 and 2 underwent redo ablation; 147/201 and 414/456 received left atrial appendage and coronary sinus isolation and 54/201 and 42/456 had left atrial lines and flutter ablation. At 2 years after the redo, 134 (91.1%) and 391 (94.4%) patients from group 1 and 2 receiving left atrial appendage/coronary sinus isolation remained arrhythmia-free whereas sinus rhythm was maintained in 4 (7.4%) and 3 (7.1%) patients in respective groups undergoing empirical lines and flutter ablation (P<0.001). Conclusions Very late recurrence of atrial fibrillation after successful isolation of pulmonary veins, regardless of the comorbidity profile, was majorly driven by non-pulmonary vein triggers and ablation of these foci resulted in high success rate. However, presence of comorbidities was associated with significantly earlier recurrence.

Essentials of Paroxysmal Supraventricular Tachycardia for the Pediatrician.

Paroxysmal supraventricular tachycardia (SVT) is the most common clinical arrhythmia in young patients. With an estimated prevalence of roughly 1 in 500 children, a pediatrician may knowingly or unknowingly see several patients who are affected each year. SVT symptoms can sometimes be vague or conflated with common pediatric complaints. Different forms of SVT are predominant at different ages, sometimes complicating timely recognition and referral. Differing pathophysiology and age distribution impact risk of complications such as heart failure, or rarely, sudden death. Treatment choices continue to evolve as new medications, monitoring devices, and ablation technologies continue to mature. This review focuses on the most common types of paroxysmal SVT: atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and Wolff-Parkinson White syndrome. Atrial arrhythmia mechanisms are also briefly outlined. It is meant to provide practical guidelines for the diagnosis and management of patients with SVT from infancy through adolescence. [Pediatr Ann. 2021;50(3):e113-e120.].

Prevalence and incidence of patients with paroxysmal supraventricular tachycardia in the United States.

BACKGROUND: Paroxysmal supraventricular tachycardia (PSVT) encompasses a range of heart rhythm disorders leading to rapid heart rates. By virtue of its episodic nature, diagnosing PSVT is difficult and estimating incidence and prevalence on a population level is challenging. The objective of this study was to estimate the incidence and prevalence of PSVT in the United States (US) in contemporary practice. METHODS AND RESULTS: An observational retrospective longitudinal study using claims, enrollment, and demographic data from the IBM MarketScan® Commercial Research database (age < 65) and the Medicare Limited Data Set (age ≥ 65) from 2008 to 2016. Patients with a PSVT diagnosis code (ICD-9: 427.0; ICD-10: I47.1) on ≥2 outpatient, ≥1 emergency room, or ≥1 inpatient visit were considered as having PSVT. Patients with atrial fibrillation/atrial flutter (AF/AFL) were excluded from the initial analysis given the potential for misclassification. Incidence was estimated by assessing diagnoses made during year 5 of continuous enrollment. Finally, a sensitivity analysis was performed by including patients with both PSVT and AF/AFL diagnoses. Period prevalence and incidence rate were estimated to be 332.9 (323.2-342.9) and 57.8 (52.8-63.3) per 100 000 individuals, respectively, when excluding patients with AF/AFL. Projected to the 2018 US Census, prevalence and incidence are 1.26 million (1.21-1.30 million) and 188,981 (172,891-206,943), respectively. Including patients with AF/AFL, the prevalence may increase to 479.7 (467.9-491.8) with an incidence of 93.4 (86.9-100.5) per 100 000 individuals or a prevalence of 2.06 million (2.01-2.12 million). CONCLUSIONS: Approximately 1 in 300 people in the US had PSVT with the highest rates in older and female patients.

Trends in health care resource use and expenditures in patients with newly diagnosed paroxysmal supraventricular tachycardia in the United States.

BACKGROUND: Few data are available on the temporal patterns of health resource utilization (HRU) and expenditures around paroxysmal supraventricular tachycardia (PSVT) diagnosis. This study assessed the longitudinal trends in HRU and expenditures in the 3 years preceding and subsequent to PSVT diagnosis. METHODS: Adult patients (age 18-65 years) with newly diagnosed PSVT were identified using administrative claims from the IBM MarketScan Research Database between January 1, 2008 and December 31, 2016 and propensity-score matched (1:1) with non-PSVT controls. RESULTS: Among the 12,305 PSVT patients compared with matched controls, PSVT was associated with statistically significant higher annual rates of emergency department visits, physician office visits, inpatient hospitalizations, and diagnostic testing. HRU increased in the years preceding PSVT diagnosis, reaching its peak in the year following PSVT diagnosis. Over the 6-year follow-up period, PSVT was associated with higher mean annual per patient expenditures ($12,665) compared to matched controls ($6,004; P < .001). Upon diagnosis of PSVT, the mean expenditures per PSVT patient doubled from $11,714 in the year immediately preceding index diagnosis to $23,335 in the first postdiagnosis year. Inpatient services, diagnostic testing, and ablation procedures were the principle drivers of higher mean expenditures in the first year post-PSVT diagnosis versus the year prior to PSVT diagnosis. CONCLUSIONS: PSVT presents a substantial economic burden to health care systems. The annual expenditure per PSVT patient is within the range previously reported for atrial fibrillation. The increased HRU and expenditures in the year following diagnosis, which do not return to baseline, suggest a potential gap in non-interventional, long-term PSVT management.

Is paroxysmal supraventricular tachycardia truly benign? Insightful association between PSVT and stroke from a National Inpatient Database Study.

BACKGROUND: Atrial fibrillation and flutter are well-known causes of stroke. Whether other atrial arrhythmias categorized as paroxysmal supraventricular tachycardia (PSVT) are associated with stroke is less clear. We aimed to evaluate the association of PSVT with ischemic and embolic stroke and its impact on short-term outcomes in hospitalized stroke patients. METHODS: National Inpatient Sample database of the USA was used to assess the association of PSVT with ischemic stroke. Atrial fibrillation and flutter were excluded to minimize the confounding effects. The association of PSVT with stroke was evaluated using univariate and multivariate analysis. Subgroup analyses by gender, age, and stroke type were also performed. RESULTS: PSVT was associated with increased odds of overall ischemic stroke in univariate [OR 1.18 (95% CI 1.09-1.27) p < 0.001] analysis. No such association was observed in multivariate analysis (OR 1.06 (95% CI 0.98-1.14) p = 0.1) or with subgroup analysis by gender and age. However, PSVT was associated with embolic stroke in both univariate (OR 2.01 (95%CI 1.67-2.43, p < 0.001) and multivariate analysis (OR 1.7 (95%CI 1.4-2.14) p < 0.001) as well as in subgroup analyses by gender and age. Furthermore, the presence of PSVT was associated with increased mortality in embolic stroke (OR 4.11, CI 2.29 to 7.39, p < 0.001) and increased total hospital cost and length of hospital stay in all stroke types. CONCLUSIONS: PSVT is independently associated with higher prevalence of embolic stroke but not with overall ischemic stroke. Patients with embolic stroke in the presence of PSVT have worse in-hospital outcomes with increased mortality.

Hospitalization rate of paroxysmal supraventricular tachycardia in Sweden.

INTRODUCTION: The hospitalization rate of paroxysmal supraventricular tachycardia (PSVT) in a nationwide study is not established. We determined age- and sex-specific hospitalization rates and time trends for hospitalized PSVT in the Swedish population between 1987 and 2010. METHODS: This nationwide study is based on the Swedish Hospital Discharge Register. The patients with first PSVT diagnoses between January 1987 and December 2010 were identified. RESULTS: A total of 42,765 individuals with PSVT were diagnosed (mean age 60 years; 44% males). The overall age- and sex-adjusted hospitalization rate was 20 per 100,000 person-years. The hospitalization rate increased with advancing age with highest hospitalization rates in individuals aged 80-84 years (67.12 per 100,000 person-years) and did not change significantly over time. A total of 20,011 (46.8%) patients had "lone" PSVT without any comorbidities. Lone PSVT patients were younger than PSVT patients with comorbidities (mean age 54 vs. 67 years, p = .0002). CONCLUSIONS: This study showed a slight preponderance for females and stable hospitalization rate of PSVT over time; the hospitalization rate increased with age. A high proportion of PSVT patients had no comorbidities. They were affected at a younger age than patients with comorbidities, which suggests an inherent predisposition. Key messages This study represents the first extensive and nationwide hospitalization study of PSVT. Hospitalization is highest in old age but a bimodal pattern was observed with a small peak in the first years of life. Patients with lone PSVT are younger than those with comorbidities; which suggests an inherent predisposition.

Contemporary Burden and Correlates of Symptomatic Paroxysmal Supraventricular Tachycardia.

BACKGROUND: Contemporary data about symptomatic paroxysmal supraventricular tachycardia (PSVT) epidemiology are limited. We characterized prevalence and correlates of symptomatic PSVT within a large healthcare delivery system and estimated national PSVT burden. METHODS AND RESULTS: We identified adults with an encounter for potential PSVT between 2010 and 2015 in Kaiser Permanente Northern California, excluding those with prior known atrial fibrillation or atrial flutter. We adjudicated medical records, ECGs, and other monitoring data to estimate positive predictive values for targeted International Classification of Diseases (ICD), 9th and 10th Revisions codes in inpatient, emergency department, and outpatient settings. Combinations of diagnosis codes and settings were used to calculate PSVT prevalence, and PSVT correlates were identified using multivariable regression. We estimated national rates by applying prevalence estimates in Kaiser Permanente to 2010 US Census data. The highest positive predictive values included codes for "PSVT" in the emergency department (82%), "unspecified cardiac dysrhythmia" in the emergency department (27%), "anomalous atrioventricular excitation" as a primary inpatient diagnosis (33%), and "unspecified paroxysmal tachycardia" as a primary inpatient diagnosis (23%). Prevalence of symptomatic PSVT was 140 per 100 000 (95% confidence interval, 100-179) and was higher for individuals who were older, women, white or black, or who had valvular heart disease, heart failure, diabetes mellitus, lung disease, or prior bleeding. We estimate the national prevalence of symptomatic PSVT to be 168 per 100 000 (95% confidence interval, 120-215). CONCLUSIONS: Selected diagnostic codes in inpatient and emergency department settings may be useful to identify symptomatic PSVT episodes. We project that at least 0.168% of US adults experience symptomatic PSVT, and certain characteristics can identify people at higher risk.

Association of Burden of Atrial Fibrillation With Risk of Ischemic Stroke in Adults With Paroxysmal Atrial Fibrillation: The KP-RHYTHM Study.

Importance: Atrial fibrillation is a potent risk factor for stroke, but whether the burden of atrial fibrillation in patients with paroxysmal atrial fibrillation independently influences the risk of thromboembolism remains controversial. Objective: To determine if the burden of atrial fibrillation characterized using noninvasive, continuous ambulatory monitoring is associated with the risk of ischemic stroke or arterial thromboembolism in adults with paroxysmal atrial fibrillation. Design, Setting, and Participants: This retrospective cohort study conducted from October 2011 and October 2016 at 2 large integrated health care delivery systems used an extended continuous cardiac monitoring system to identify adults who were found to have paroxysmal atrial fibrillation on 14-day continuous ambulatory electrocardiographic monitoring. Exposures: The burden of atrial fibrillation was defined as the percentage of analyzable wear time in atrial fibrillation or flutter during the up to 14-day monitoring period. Main Outcomes and Measures: Ischemic stroke and other arterial thromboembolic events occurring while patients were not taking anticoagulation were identified through November 2016 using electronic medical records and were validated by manual review. We evaluated the association of the burden of atrial fibrillation with thromboembolism while not taking anticoagulation after adjusting for the Anticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) or CHA2DS2-VASc stroke risk scores. Results: Among 1965 adults with paroxysmal atrial fibrillation, the mean (SD) age was 69 (11.8) years, 880 (45%) were women, 496 (25%) were persons of color, the median ATRIA stroke risk score was 4 (interquartile range [IQR], 2-7), and the median CHA2DS2-VASc score was 3 (IQR, 1-4). The median burden of atrial fibrillation was 4.4% (IQR ,1.1%-17.23%). Patients with a higher burden of atrial fibrillation were less likely to be women or of Hispanic ethnicity, but had more prior cardioversion attempts compared with those who had a lower burden. After adjusting for either ATRIA or CHA2DS2-VASc stroke risk scores, the highest tertile of atrial fibrillation burden (≥11.4%) was associated with a more than 3-fold higher adjusted rate of thromboembolism while not taking anticoagulants (adjusted hazard ratios, 3.13 [95% CI, 1.50-6.56] and 3.16 [95% CI, 1.51-6.62], respectively) compared with the combined lower 2 tertiles of atrial fibrillation burden. Results were consistent across demographic and clinical subgroups. Conclusions and Relevance: A greater burden of atrial fibrillation is associated with a higher risk of ischemic stroke independent of known stroke risk factors in adults with paroxysmal atrial fibrillation.

Clinical Impact of Asymptomatic Presentation Status in Patients With Paroxysmal and Sustained Atrial Fibrillation: The Fushimi AF Registry.

BACKGROUND: The clinical characteristics and outcomes of asymptomatic patients with paroxysmal or persistent/permanent atrial fibrillation (AF) are largely unknown. METHODS: The Fushimi AF Registry is a community-based prospective survey of patients with AF who visited the participating medical institutions in Fushimi-ku, Japan. We investigated the clinical characteristics and outcomes of asymptomatic vs symptomatic patients in the paroxysmal AF (PAF; n = 1,837) and persistent/permanent (sustained atrial fibrillation [SAF]; n = 1,912) subgroups. RESULTS: In the PAF group, asymptomatic patients were older (asymptomatic vs symptomatic group, 74.1 vs 71.1 years of age; P < .01), more often male (62.1% vs 55.6%; P < .01), and had a higher CHA2DS2-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, history of stroke, vascular disease, age 65-74 years, and female sex) score (mean, 3.37 ± 1.73 vs 2.99 ± 1.63; P < .01), whereas the prevalence of major co-morbidities and CHA2DS2-VASc scores were comparable in the SAF group. Multivariable analysis indicated that age (≥ 75 years), history of stroke/systemic embolism, male sex, and chronic kidney disease were independent determinants of asymptomatic status in the PAF group, whereas age was nonsignificant in the SAF group. During the follow-up period, all-cause mortality was significantly higher (hazard ratio, 1.71 [95% CI, 1.31-2.29]; P < .01) in asymptomatic patients compared with symptomatic patients in the PAF group, whereas it was comparable in the SAF group. CONCLUSIONS: Asymptomatic clinical status is associated with older age, male sex, more co-morbidities with a higher stroke risk profile, and a higher incidence of all-cause death in patients with PAF; these characteristics and outcomes were not seen in the SAF group. TRIAL REGISTRY: UMIN Clinical Trials Registry; No.: UMIN000005834; URL: www.umin.ac.jp/ctr/index.htm.

Association of Paroxysmal Supraventricular Tachycardia with Ischemic Stroke: A National Case-Control Study.

BACKGROUND AND PURPOSE: Cardioembolic stroke accounts for approximately 15%-20% of all ischemic strokes. Atrial fibrillation constitutes one-half to two-thirds of all cardioembolic stroke events. The association of paroxysmal supraventricular tachycardia (PSVT) with ischemic stroke remains unclear. A national case-control study was conducted to identify the risk factors, including PSVT, for ischemic stroke in Taiwan. METHODS: We designed a national case-control study comprising patients diagnosed with ischemic stroke (n = 5633) from 1997 to 2011; each patient from the case group was randomly matched with the control group (n = 30,895) in Taiwan. Data were retrospectively collected from Taiwan's National Health Insurance Research Database, which contains not only claims data on hospitalization, emergency room visits, and outpatient department visits, but also patient characteristics. RESULTS: Logistic regression analysis was used to identify the risk factors for ischemic stroke. Independent risk factors for ischemic stroke included age (in 5-year intervals; odds ratio [OR], 1.76; 95% confidence interval [CI], 173-1.78), the male sex (versus the female sex; OR, 1.88; 95% CI, 1.74-2.01), chronic kidney disease (OR, 3.09; 95% CI, 2.67-3.57), PSVT (OR, 2.05; 95% CI, 1.30-3.19), and aspirin use (OR, .04; 95% CI, .03-0.05). CONCLUSIONS: Our study is the first in Taiwan to identify PSVT as a significant risk factor for ischemic stroke. New antithrombotic regimens, including aspirin, can be recommended for the primary prevention of stroke and for reducing the burden of stroke for patients with PSVT.

Progression of paroxysmal to persistent atrial fibrillation: 10-year follow-up in the Canadian Registry of Atrial Fibrillation.

BACKGROUND: Progression from paroxysmal to persistent atrial fibrillation (AF) has important clinical implications and is relevant to the management of patients with AF. OBJECTIVE: The purpose of this study was to define the long-term rate of progression from paroxysmal to persistent AF and the relevant clinical variables. METHODS: The Canadian Registry of Atrial Fibrillation enrolled patients after a first electrocardiographic diagnosis of paroxysmal AF. Associations between baseline characteristics and clinical outcomes were evaluated using a multivariable Cox proportional hazard model and a competing risk model accounting for death as a competing risk, where appropriate. RESULTS: We enrolled 755 patients (61.7% men) aged between 14 and 91 years (mean age 61.2 ± 14.2 years). The median follow-up was 6.35 years (interquartile range 2.93-10.04 years), with a rate of progression to persistent AF at 1, 5, and 10 years was 8.6%, 24.3%, and 36.3%, respectively. All-cause mortality was 30.3% at 10 years. Factors associated with AF progression were increasing age (hazard ratio [HR] 1.40; 95% confidence interval [CI] 1.23-1.60, for each 10-year increment), mitral regurgitation (HR 1.87; 95% CI 1.28-2.73), left atrial dilatation (HR 3.01; 95% CI 2.03-4.47), aortic stenosis (HR 2.40; 95% CI 1.05-5.48), and left ventricular hypertrophy (HR .47; 95% CI 1.04-2.08). Factors associated with a lower rate of progression were a faster heart rate during AF (HR 0.94; 95% CI 0.92-0.96 per 5-beat/min increment) and angina (HR 0.54; 95% CI 0.38-0.77). After accounting for death as a competing risk, left ventricular hypertrophy and aortic stenosis were no longer significant. CONCLUSION: Within 10 years of presenting with paroxysmal AF, >50% of patients will progress to persistent AF or be dead. Increasing age, mitral regurgitation, aortic stenosis, left ventricular hypertrophy, and left atrial dilatation were associated with progression to persistent AF.

Second-generation cryoballoon ablation for paroxysmal atrial fibrillation: Predictive role of atrial arrhythmias occurring in the blanking period on the incidence of late recurrences.

BACKGROUND: Although consensus documents on catheter and surgical ablation of atrial fibrillation (AF) suggest a uniform "blanking period" of 3 months, recent evidence suggested that early recurrences of atrial tachyarrhythmias (ERATs) are strongly associated with late recurrences (LRs), especially if ERATs occurred in the last part of the "blanking period". OBJECTIVE: The present study sought to assess the role of ERATs in predicting LRs in a large cohort of patients with paroxysmal AF who have undergone second-generation cryoballoon ablation. METHODS: Consecutive patients with drug-resistant paroxysmal AF who underwent pulmonary vein isolation using CB-A technology as the index procedure were retrospectively included in our analysis. The exclusion criteria were any contraindications for the procedure, including the presence of an intracavitary thrombus, uncontrolled heart failure, contraindications to general anesthesia, and persistent AF. RESULTS: A total of 331 consecutive patients (104 women [31%]; mean age 56.7 ± 13.3 years) were enrolled. Atrial tachyarrhythmias/AF recurrences were detected in 57 patients (17.2%). The highest prevalence of ERATs was observed in the first 2 weeks (55%) after pulmonary vein isolation. Of note, all the ERATs occurring 1.5 months after AF ablation relapsed after 3 months and were confirmed as definitive recurrences. Late recurrence of AF and atrial tachycardia occurred in 20 of 29 patients with ERATs (69.0%) and 28 of 302 patients without ERATs (9.3%) (P < .0001). A multivariate Cox regression analysis showed that the early recurrence within the blanking period was significantly and independently associated with an increased risk of developing a late recurrence (hazard ratio 6.79; 95% confidence interval 3.52-10.14; P < .0001). CONCLUSION: Our findings reveal that ERATs are strongly associated with an LR after paroxysmal AF ablation using CB-A technology (hazard ratio 6.79; 95% confidence interval 3.52-10.14; P < .0001). Of note, when ERATs occurred later than 1.5 months, patients systematically experienced an LR.

Long-term Prognosis of Paroxysmal Atrial Fibrillation and Predictors for Progression to Persistnt or Chronic Atrial Fibrillation in the Korean Population.

Little is known about the long-term prognosis of or predictors for the different clinical types of atrial fibrillation (AF) in Korean populations. The aim of this study was to validate a risk stratification to assess the probability of AF progression from paroxysmal AF (PAF) to persistent AF (PeAF) or permanent AF. A total of 434 patients with PAF were consecutively enrolled (mean age; 71.7 ± 10.7 yr, 60.6% male). PeAF was defined as episodes that are sustained > 7 days and not self-terminating, while permanent AF was defined as an ongoing long-term episode. Atrial arrhythmia during follow-up was defined as atrial premature complex, atrial tachycardia, and atrial flutter. During a mean follow-up of 72.7 ± 58.3 months, 168 patients (38.7%) with PAF progressed to PeAF or permanent AF. The mean annual AF progression was 10.7% per year. In univariate analysis, age at diagnosis, body mass index, atrial arrhythmia during follow-up, left ventricular ejection fraction, concentric left ventricular hypertrophy, left atrial diameter (LAD), and severe mitral regurgitation (MR) were significantly associated with AF progression. In multivariate analysis, age at diagnosis (P = 0.009), atrial arrhythmia during follow-up (P = 0.015), LAD (P = 0.002) and MR grade (P = 0.026) were independent risk factors for AF progression. Patients with younger age at diagnosis, atrial arrhythmia during follow-up, larger left atrial chamber size, and severe MR grade are more likely to progress to PeAF or permanent AF, suggesting more intensive medical therapy with close clinical follow-up would be required in those patients.

Predictors of new onset atrial fibrillation during 10-year follow-up after first-ever ischemic stroke.

BACKGROUND: Paroxysmal atrial fibrillation (AF) may be underdiagnosed in ischemic stroke patients but may be pivotal for initiation of oral anticoagulation therapy. We assessed clinical and ECG predictors of new-onset AF during 10-year follow-up (FU) in ischemic stroke patients. METHODS: The study sample comprised of 227 first-ever ischemic stroke patients without AF (median age 73, interquartile range 25%-75% 63-80years, 92 female) and 1:1 age- and gender-matched controls without stroke and AF enrolled in the Lund Stroke Register from March 2001 to February 2002. New-onset AF during FU was assessed by screening through regional ECG database and by record linkage with Swedish National Patient Register. The standard 12-lead sinus rhythm ECGs at stroke admission were retrieved from electronic database and digitally processed. Clinical baseline characteristics were studied using medical records. RESULTS: During FU, AF was found in 39 stroke patients and 30 controls, p=0.296. In stroke patients in multivariate Cox regression analysis AF was associated with hypertension (HR 3.45 CI 95% 1.40-3.49, p=0.007) and QRS duration (HR 1.02 CI 95% 1.00-1.03, p=0.049). High cardiovascular risk was predictive for AF development: for CHADS2≥4 HR 2.46 CI 95% 1.45-4.18, p=0.001 and for CHA2DS2-VASc≥5 HR 2.29 CI 95% 1.43-3.68, p=0.001. New onset AF was not associated with baseline ischemic stroke: HR 1.46 95% CI 0.90-2.35, p=0.121. CONCLUSION: High CHADS2 and CHA2DS2-VASc scores, but not baseline ischemic stroke, predict new onset AF in FU. QRS duration might be considered a potential risk marker for prediction of AF after ischemic stroke.

Electrophysiological studies in patients with paroxysmal supraventricular tachycardias but no electrocardiogram documentation: findings from a prospective registry.

AIMS: A significant proportion of patients presenting with paroxysmal supraventricular tachycardia (PSVT) has no electrocardiogram (ECG) documentation. In these patients an electrophysiological study (EPS) may be performed to facilitate the diagnosis. METHODS AND RESULTS: In a prospective registry we compared the prevalence of inducible arrhythmias and the clinical outcome in 525 patients with and without ECG documentation. Compared with patients with a documented PSVT a smaller but substantial proportion of patients (63.7%) without ECG documentation had inducible supraventricular tachycardias (SVT). Atrio-ventricular nodal reentrant tachycardia was the most common type in both groups. Patients with an inducible SVT and no documentation were significantly younger, had a shorter episode duration and a lower hospitalization rate, which may be the cause for the lacking documentation. Similar to patients with documented PSVTs most of these patients (90.0%) were asymptomatic or clinically improved after the EPS. Even 43% of patients without an inducible tachycardia improved clinically, probably due to a placebo effect of the EPS. In particular, patients between 31 and 60 years of age seemed to benefit from an EPS because they were more likely to have inducible SVTs that could be cured by radiofrequency ablation. CONCLUSION: Our data show that a substantial proportion of patients with suspected paroxysmal tachycardia, but without ECG documentation, have inducible SVTs and obtain a clear clinical benefit from an EPS. Thus, our data provide justification for using EPS for patients in this category. To the best of our knowledge, ours is the first prospective registry that supports this approach.

Long-term Prognosis of Paroxysmal Atrial Fibrillation and Predictors for Progression to Persistnt or Chronic Atrial Fibrillation in the Korean Population

Little is known about the long-term prognosis of or predictors for the different clinical types of atrial fibrillation (AF) in Korean populations. The aim of this study was to validate a risk stratification to assess the probability of AF progression from paroxysmal AF (PAF) to persistent AF (PeAF) or permanent AF. A total of 434 patients with PAF were consecutively enrolled (mean age; 71.7 +/- 10.7 yr, 60.6% male). PeAF was defined as episodes that are sustained > 7 days and not self-terminating, while permanent AF was defined as an ongoing long-term episode. Atrial arrhythmia during follow-up was defined as atrial premature complex, atrial tachycardia, and atrial flutter. During a mean follow-up of 72.7 +/- 58.3 months, 168 patients (38.7%) with PAF progressed to PeAF or permanent AF. The mean annual AF progression was 10.7% per year. In univariate analysis, age at diagnosis, body mass index, atrial arrhythmia during follow-up, left ventricular ejection fraction, concentric left ventricular hypertrophy, left atrial diameter (LAD), and severe mitral regurgitation (MR) were significantly associated with AF progression. In multivariate analysis, age at diagnosis (P = 0.009), atrial arrhythmia during follow-up (P = 0.015), LAD (P = 0.002) and MR grade (P = 0.026) were independent risk factors for AF progression. Patients with younger age at diagnosis, atrial arrhythmia during follow-up, larger left atrial chamber size, and severe MR grade are more likely to progress to PeAF or permanent AF, suggesting more intensive medical therapy with close clinical follow-up would be required in those patients.

Association of certain chronic maternal diseases with the risk of specific congenital heart defects: a population-based study.

OBJECTIVE: Previous epidemiological studies have evaluated cases with all congenital heart defects (CHDs), rather than analysing different types of CHD. The objective of this study was to evaluate the possible association of certain chronic maternal diseases with the risk of different types of CHD, because the role of possible environmental factors in the origin of CHDs is unclear in the vast majority of patients. STUDY DESIGN: Different types of CHD, diagnosed after lethal outcome (autopsy report) or after surgical intervention (catheter or correction), were evaluated in order to estimate the possible role of chronic maternal diseases in their origin. This analysis was based on the rates of medically recorded chronic maternal diseases in 3562 live-born cases with CHDs, 38,151 population controls without any birth defects, and 16,602 malformed controls with other isolated congenital abnormalities, using the data set of the population-based Hungarian Case-Control Surveillance of Congenital Abnormalities (1980-1996). RESULTS: Maternal epilepsy treated with carbamazepine and migraine were found to be associated with higher risk of ventricular septal defect; panic disorders were associated with higher risk of hypoplastic left heart; type I diabetes mellitus was associated with higher risk of coarctation of the aorta; chronic hypertension was associated with higher risk of ventricular septal defect, common atrioventricular canal and common truncus; and paroxysmal supraventricular tachycardia was associated with higher risk of atrial septal defect secundum, common atrioventricular canal and ventricular septal defect. CONCLUSION: In conclusion, certain chronic maternal diseases were found to be associated with higher risk of specific CHDs. Appropriate treatment of these diseases may help to prevent these CHDs.

Impact of metabolic syndrome on left atrial electroanatomical remodeling and outcomes after radiofrequency ablation of nonvalvular atrial fibrillation.

BACKGROUND: Recent studies reported worse outcomes after atrial fibrillation (AF) ablation in patients with metabolic syndrome (MetS). However, mechanisms of AF recurrence in MetS remain unclear. METHOD AND RESULTS: We performed pulmonary vein isolation and voltage mapping in 236 patients with AF (age 61±9.6 years; persistent AF 64%; MetS 54%). Left atrial (LA) low voltage areas were semiquantitatively estimated and presented as low voltage index. MetS was defined according to National Cholesterol Education Program Adult Treatment Panel III. Follow-up for AF recurrence ≤12 months was performed. LA low voltage areas were observed in 46% of patients with MetS versus 8.2% patients without MetS ; P<0.0001. MetS was an independent predictor of LA low voltage areas: odds ratio, 11.64; 95% confidence interval, 4.381-30.903; P<0.0001. Observed AF recurrence at 12 months was 42.7% in MetS versus 36.1% in the non-MetS group (P=0.303). The presence of LA low voltage areas was a predictor of 12-month AF recurrence: odds ratio, 2.99; 95% confidence interval, 1.36-6.56; P=0.006. Probability of 12-month AF recurrence increased with 84.5% for every unit of low voltage Index. CONCLUSIONS: MetS was not associated with worse outcomes after radiofrequency catheter ablation of AF, but LA low voltage areas were more frequently observed in patients with MetS. The presence and extent of LA low voltage areas may influence the long-term outcomes after catheter ablation.