Electrocardiographic ST-T Abnormities Are Associated With Stroke Risk in the REGARDS Study.

Background and Purpose- In previous studies, isolated nonspecific ST-segment and T-wave abnormalities (NSSTTAs), a common finding on ECGs, were associated with greater risk for incident coronary artery disease. Their association with incident stroke remains unclear. Methods- The REGARDS (Reasons for Geographic and Racial Differences in Stroke) study is a population-based, longitudinal study of 30 239 white and black adults enrolled from 2003 to 2007 in the United States. NSSTTAs were defined from baseline ECG using the standards of Minnesota ECG Classification (Minnesota codes 4-3, 4-4, 5-3, or 5-4). Participants with prior stroke, coronary heart disease, and major and minor ECG abnormalities other than NSSTTAs were excluded from analysis. Multivariable Cox proportional hazards regression was used to examine calculate hazard ratios of incident ischemic stroke by presence of baseline NSSTTAs. Results- Among 14 077 participants, 3111 (22.1%) had NSSTTAs at baseline. With a median of 9.6 years follow-up, 106 (3.4%) with NSSTTAs had ischemic stroke compared with 258 (2.4%) without NSSTTAs. The age-adjusted incidence rates (per 1000 person-years) of stroke were 2.93 in those with NSSTTAs and 2.19 in those without them. Adjusting for baseline age, sex, race, geographic location, and education level, isolated NSSTTAs were associated with a 32% higher risk of ischemic stroke (hazard ratio, 1.32 [95% CI, 1.05-1.67]). With additional adjustment for stroke risk factors, the risk of stroke was increased 27% (hazard ratio, 1.27 [95% CI, 1.00-1.62]) and did not differ by age, race, or sex. Conclusions- Presence of NSSTTAs in persons with an otherwise normal ECG was associated with a 27% increased risk of future ischemic stroke.

Cardiac biomarkers of prognostic importance in chronic obstructive pulmonary disease.

BACKGROUND: Ischemic heart disease is common in COPD and associated with worse prognosis. This study aimed to investigate the presence and prognostic impact of biomarkers of myocardial injury and ischemia among individuals with COPD and normal lung function, respectively. METHODS: In 2002-04, all individuals with airway obstruction (FEV1/VC < 0.70, n = 993) were identified from population-based cohorts, together with age and sex-matched non-obstructive referents. At re-examination in 2005, spirometry, Minnesota-coded ECG and analyses of high-sensitivity cardiac troponin I (hs-cTnI) were performed in individuals with COPD (n = 601) and those with normal lung function (n = 755). Deaths were recorded until December 31st, 2010. RESULTS: Hs-cTnI concentrations were above the risk stratification threshold of ≥5 ng/L in 31.1 and 24.9% of those with COPD and normal lung function, respectively. Ischemic ECG abnormalities were present in 14.8 and 13.4%, while 7.7 and 6.6% had both elevated hs-cTnI concentrations and ischemic ECG abnormalities. The 5-year cumulative mortality was higher in those with COPD than those with normal lung function (13.6% vs. 7.7%, p < 0.001). Among individuals with COPD, elevated hs-cTnI both independently and in combination with ischemic ECG abnormalities were associated with an increased risk for death (adjusted hazard ratio [HR]; 95% confidence interval [CI] 2.72; 1.46-5.07 and 4.54; 2.25-9.13, respectively). Similar associations were observed also among individuals with COPD without reported ischemic heart disease. CONCLUSIONS: In this study, elevated hs-cTnI concentrations in combination with myocardial ischemia on the electrocardiogram were associated with a more than four-fold increased risk for death in a population-based COPD-cohort, independent of disease severity.

Heart rate variability is depressed in the early transitional period for newborns with complex congenital heart disease.

PURPOSE: To compare early changes in autonomic nervous system (ANS) tone between newborns with complex congenital heart disease (CHD) and newborns without CHD. METHODS: We performed a case-control study of heart rate variability (HRV) in newborns with complex CHD [transposition of the great arteries (TGA) or hypoplastic left heart syndrome (HLHS)] and low-risk control newborns without CHD. Cases with CHD were admitted following birth to a pediatric cardiac intensive care unit and had archived continuous ECG data. Control infants were prospectively enrolled at birth. ECG data in cases and controls were analyzed for HRV in the time and frequency domains at 24 h of age. We analyzed the following HRV metrics: alpha short (αs), alpha long (αL), root mean square short and long (RMSs and RMSL), low-frequency (LF) power, normalized LF (nLF), high-frequency (HF) power, and normalized HF (nHF). We used ANOVA to compare HRV metrics between groups and to control for medication exposures. RESULTS: HRV data from 57 infants with CHD (TGA, n = 33 and HLHS, n = 24) and from 29 controls were analyzed. The HRV metrics αS, RMSL, LF, and nLF were significantly lower in infants with CHD than in the controls. Due to the effect of normalization, nHF was higher in CHD infants (P < 0.0001), although absolute HF was lower (P = 0.0461). After adjusting for medications, αS and nLF remained lower and nHF higher in newborns with CHD (P < 0.0005). CONCLUSIONS: Infants with complex CHD have depressed autonomic balance in the early postnatal period, which may complicate the fetal-neonatal transition.

Atrial Fibrillation Known Before or Detected After Stroke Share Similar Risk of Ischemic Stroke Recurrence and Death.

Background and Purpose- We aim to compare the risk of 1-year ischemic stroke recurrence and death for atrial fibrillation diagnosed after stroke (AFDAS), atrial fibrillation known before stroke (KAF), and sinus rhythm (SR). Methods- From June 2012 to January 2013, 19 604 patients with acute ischemic stroke were admitted to 219 urban hospitals in the China National Stroke Registry II. Based on heart rhythm assessed during admission, we classified patients as AFDAS, KAF, or SR. We explored the relationship between heart rhythm groups and 1-year ischemic stroke recurrence or death by using Cox regression adjusted for multiple covariates. Considering that death is a competing risk for stroke recurrence, we used the competing risks analysis of Fine and Gray and subdistribution Cox proportional hazards to test the association between heart rhythm and 1-year outcomes. Results- Among 19 604 ischemic stroke patients, 17 727 had SR, 495 AFDAS, and 1382 KAF. At 1 year, 54 (10.9%) patients with AFDAS, 182 (13.2%) with KAF, and 1008 (5.7%) with SR had recurrent ischemic strokes ( P<0.0001). Mortality was 22.0% in patients with AFDAS, 22.1% in patients with KAF, and 7.0% in patients with SR ( P<0.0001). AFDAS-related ischemic stroke recurrence adjusted risk was higher than that of SR (adjusted subdistribution hazard ratios, 1.61; 95% CI, 1.29-2.01) but not different from that of KAF (adjusted subdistribution hazard ratio, 1.12; 95% CI, 0.87-1.45]). The adjusted risk of 1-year death for AFDAS was also higher than that of SR (hazard ratio, 1.70; 95% CI, 1.37-2.12) and not different from that of KAF (hazard ratio, 1.10; 95% CI, 0.86-1.41). Conclusions- This study showed that AFDAS had similar risk of 1-year ischemic stroke recurrence and mortality when compared with KAF and higher risk when compared with SR. The potential risk of AFDAS should be given more emphasis, and appropriate treatment is needed to achieve reduction in the incidence of stroke recurrence and mortality.

The yield of long-term electrocardiographic recordings in refractory focal epilepsy.

OBJECTIVE: To determine the incidence of clinically relevant arrhythmias in refractory focal epilepsy and to assess the potential of postictal arrhythmias as risk markers for sudden unexpected death in epilepsy (SUDEP). METHODS: We recruited people with refractory focal epilepsy without signs of ictal asystole and who had at least one focal seizure per month and implanted a loop recorder with 2-year follow-up. The devices automatically record arrhythmias. Subjects and caregivers were instructed to make additional peri-ictal recordings. Clinically relevant arrhythmias were defined as asystole ≥ 6 seconds; atrial fibrillation < 55 beats per minute (bpm), or > 200 bpm and duration > 30 seconds; persistent sinus bradycardia < 40 bpm while awake; and second- or third-degree atrioventricular block and ventricular tachycardia/fibrillation. We performed 12-lead electrocardiography (ECG) and tilt table testing to identify non-seizure-related causes of asystole. RESULTS: We included 49 people and accumulated 1060 months of monitoring. A total of 16 474 seizures were reported, of which 4679 were captured on ECG. No clinically relevant arrhythmias were identified. Three people had a total of 18 short-lasting (<6 seconds) periods of asystole, resulting in an incidence of 2.91 events per 1000 patient-months. None of these coincided with a reported seizure; one was explained by micturition syncope. Other non-clinically relevant arrhythmias included paroxysmal atrial fibrillation (n = 2), supraventricular tachycardia (n = 1), and sinus tachycardia with a right bundle branch block configuration (n = 1). SIGNIFICANCE: We found no clinically relevant arrhythmias in people with refractory focal epilepsy during long-term follow-up. The absence of postictal arrhythmias does not support the use of loop recorders in people at high SUDEP risk.

Epileptic seizures associated with syncope: Ictal bradycardia and ictal asystole.

INTRODUCTION: Heart rate decrease during epileptic seizures is rare and should be considered in patients with unusual or refractory episodes of syncope or in patients with a history suggestive of both epilepsy and syncope. We systematically reviewed the literature to better understand the clinical signs and risk factors of ictal heart rate decreases. MATERIAL AND METHODS: We performed a literature-search on "ictal bradycardia" and "ictal asystole" in Pubmed and added papers from the references and personal archives. Articles relating to animal studies, seizures without ictal decrease of heart rate, cases without simultaneous electroencephalography (EEG) and electrocardiography (ECG), convulsive syncopes, or cases with bradycardia before seizure onset and articles written in other languages than English, Dutch, German, French, or Spanish were excluded. Full texts of the remaining articles were screened for cases of ictal bradycardia or ictal asystole. Cases were selected on the basis of a self-designed quality score. The relationship of RR wave interval of at least 5 s, signs of syncope, and EEG signs of ischemia were analyzed with chi-square test and identifying 95% confidence intervals. RESULTS: Ictal bradycardia and ictal asystole predominantly occurred during focal seizures with loss of awareness (proportion in the combined group of bradycardia and asystole (p1 + 2) = 0.85) in people with mainly left lateralized (p1 + 2 = 0.64; p = 0.001) temporal lobe seizures (p1 + 2 = 0.91). Seizures with ictal asystole typically started with a heart rate decrease. During ictal asystole in the majority of cases, not only the clinical signs of syncope occurred (change of proportion (Δp) = 0.67; 95% CI: 0.48-0.86; p < 0.0001), i.e., interrupting the seizure semiology, but also the characteristic EEG signs of ischemia (Δp = 0.50; 95% CI: 0.26-0.74; p < 0.001). We found a statistically significant relation between signs of syncope and EEG signs of ischemia (Δp = -0.37; 95% CI: (-0.64)-(-0.10); p < 0.01) but not between duration of asystole (5 s) and either signs of syncope (Δp = -0.36; 95% CI: (-0.77)-0.05; p = 0.03) or EEG signs of ischemia (Δp = -0.37; 95% CI: (-1.07)-0.33; p = 0.16). CONCLUSION: In the ictal bradycardia syndrome, signs of syncope disrupt the semiology of ongoing seizures and are associated with EEG signs of brain ischemia and the duration of the cardiac arrhythmia.

Consecutive episodes of heart and kidney failure in an "otherwise" healthy young man.

BACKGROUND: Acute renal failure is a rare occurrence in a patient with an unremarkable past medical history and should always lead to an in depth clinical study. The occurrence in the same healthy young subject, of consecutive episodes of heart failure and of acute renal failure is an even rarer event and should prompt diagnostic tests and restrict the diagnostic hypotheses. CASE PRESENTATION: We present the case of a 28 year-old man who, while waiting to undergo assessment for a mild chronic kidney disease, was diagnosed with decompensated dilated cardiomyopathy and placed on diuretics and ß-blockers. After few weeks he developed a non oligoanuric acute renal failure with a slight elevation of serum calcium. Renal biopsy proved suggestive for renal sarcoidosis; thus the hypothesis of systemic sarcoidosis with cardiac and renal involvement was possible avoiding further delay in initiation of therapy. CONCLUSIONS: Cardiac sarcoidosis is usually silent but the majority of cases are diagnosed when cardiac symptoms are present in a patient with systemic sarcoidosis. Renal involvement with granulomatous interstitial nephritis is also quite rare and can be an unexpected finding at kidney biopsy. This case highlights the need to evaluate thoroughly clinical problems that do not fit in a specific scenario and emphasizes the importance of performing a kidney biopsy in case of kidney failure of unknown etiology.

Predictors of Increased Length of Hospital Stay in Patients with Severe Cardiomyopathy Undergoing Coronary Artery Bypass Grafting.

OBJECTIVE: Predictors of operative outcome in patients with severely depressed left ventricular ejection fraction (LVEF) undergoing coronary artery bypass grafting (CABG) remain poorly defined. This study aims to identify preoperative variables that are associated with increased postoperative length of hospital stay or operative mortality in this patient population. DESIGN: Retrospective study. SETTING: Single tertiary care university hospital. PARTICIPANTS: Patients undergoing isolated CABG between January 2012 and March 2017 with an LVEF ≤ 25%. INTERVENTIONS: Isolated CABG. MEASUREMENTS AND MAIN RESULTS: Primary endpoint was a composite of prolonged length of stay, defined as postoperative length of stay >7 days or operative mortality. Of the 201 patients, 99 (49.3%) met the primary endpoint. Patient comorbidities, clinical presentation, presence of Q-waves on electrocardiogram, and echocardiographic parameters including ventricular dimensions and right heart dysfunction were not associated with the primary endpoint. On multivariable analysis, patients who were not on preoperative beta-blockers, patients with preoperative albumin of <3.5 g/dL, and higher Society of Thoracic Surgeons Predicted Risk of Mortality score were associated with increased prolonged length of stay or death. CONCLUSIONS: More than half of patients with severely depressed LVEF undergoing isolated CABG are able to be discharged within 7 days postoperatively. The absence of preoperative beta-blockers, low preoperative albumin levels, and higher Society of Thoracic Surgeons Predicted Risk of Mortality score are associated with more complicated or slower postoperative recovery after CABG in this patient population.

Preoperative QTc Interval is Not Associated With Intraoperative Cardiac Events or Mortality in Liver Transplantation Patients.

OBJECTIVES: The primary objective of this study was to determine whether liver transplantation recipients with preoperative prolonged corrected (QTc) intervals have a higher incidence of intraoperative cardiac events and/or postoperative mortality compared with their peers with normal QTc intervals. DESIGN: This was a retrospective cohort study. SETTING: Single academic hospital in New York, NY. PARTICIPANTS: Patients undergoing liver transplantation between 2007 and 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data relating to all liver transplantation recipients with preoperative electrocardiograms were queried from an institutional anesthesia data warehouse and electronic medical records. Primary outcomes were a composite outcome of intraoperative cardiac events and postoperative mortality. Patients with a prolonged QTc interval (>450 ms for men, >470 ms for women) did not demonstrate an association with intraoperative cardiac events, 30- or 90-day mortality, in-hospital mortality, or overall mortality compared with recipients in the normal QTc interval group. A prolonged QTc was found to be associated with increased anesthesia time, surgical time, length of hospital stay, and incidence of fresh frozen plasma and platelets transfusion. CONCLUSIONS: Prolonged QTc interval is not associated with an increased incidence of intraoperative cardiac events or mortality in liver transplantation recipients. The demonstrated correlation among QTc length and Model for End-stage Liver Disease score, blood component requirements, surgical and anesthetic times, and hospital length of stay likely represents the association between QTc length and severity of liver disease.

Cardiac parasympathetic activity and ventricular diastolic interactions in individuals with spinal cord injury.

STUDY DESIGN: Cohort cross-sectional study. OBJECTIVE: To investigate the relationship between cardiac vagal activity and left ventricular filling at rest and during vagal stimulation, via the cold face test (CFT), in individuals with spinal cord injury (SCI). SETTING: University-based laboratory at Brock University, St. Catharines, ON, Canada. METHODS: A total of 12 able-bodied (age: 40 ± 8.5 years) and 13 SCI individuals (age: 41 ± 8.5 years; C4-T6; AIS: A-D) were recruited. Cardiac parasympathetic activity was assessed via heart rate variability (HRV) while LV filling was assessed by conventional echocardiography. All indices of HRV and diastolic function were obtained at rest and during cardiac vagal stimulation via the CFT. RESULTS: At baseline, the able-bodied group demonstrated strong positive correlations between HRV and early diastolic filling; however, such correlations were absent in the SCI group. The CFT resulted in elevated HRV with concomitant bradycardia in the able-bodied group, while the SCI group experienced no change in HRV or heart rate during the CFT. Able-bodied individuals showed a positive correlation between the change in HRV and the change in LV diastole during the CFT, which was attributed to increased cardiac vagal tone and not the change in heart rate, however, no relationships were observed in the SCI group. CONCLUSION: In able-bodied individuals, cardiac parasympathetic activity is associated with LV filling at rest and during elevated cardiac vagal tone. After SCI, there is a discord between vagal and LV diastolic activity, where changes in autonomic function do not influence LV filling, suggesting a disconnect between parasympathetic and cardiac function.

Variation of Electrocardiogram Features Across Sleep Stages in Healthy Controls and in Patients with Sleep Apnea Hypopnea Syndrome.

Sleep apnea hypopnea syndrome (SAHS) is an independent risk factor for various cardiovascular diseases. Electrocardiogram (ECG) features such as the RR, PR, QT, QTc, Tpe intervals and the Tpe/QT, Tpe/QTc ratios are used to predict and study cardiovascular diseases. It is not clear whether regular patterns of PR and Tpe-related features across sleep stages exist in SAHSs or healthy controls nor whether sleep stages affect the short- and long-range influences of respiratory events on ECG indices. We enrolled 36 healthy controls and 35 patients with SAHS in our study and analyzed the abovementioned ECG features. In the healthy controls, a significant regularity existed in these indices across sleep stages, which were weakened or disturbed in the patient group, especially the Tpe-related features. The differences between the patients and healthy controls were generally consistent across all sleep stages: patients had smaller RR, PR, QT and Tpe/QTc values, but larger QTc, Tpe and Tpe/QT values. After filtering the short-range influence of respiratory events, the differences in most features remained highly significant, except the QT interval. In the patient group, respiratory events decreased RR and PR intervals in most sleep stages and increased the Tpe-related features' values in deep sleep stages. These results may aid in the study of the relationships among SAHS, sleep disorders and cardiovascular diseases.

Pharmacogenomics study of thiazide diuretics and QT interval in multi-ethnic populations: the cohorts for heart and aging research in genomic epidemiology.

Thiazide diuretics, commonly used antihypertensives, may cause QT interval (QT) prolongation, a risk factor for highly fatal and difficult to predict ventricular arrhythmias. We examined whether common single-nucleotide polymorphisms (SNPs) modified the association between thiazide use and QT or its component parts (QRS interval, JT interval) by performing ancestry-specific, trans-ethnic and cross-phenotype genome-wide analyses of European (66%), African American (15%) and Hispanic (19%) populations (N=78 199), leveraging longitudinal data, incorporating corrected standard errors to account for underestimation of interaction estimate variances and evaluating evidence for pathway enrichment. Although no loci achieved genome-wide significance (P<5 × 10-8), we found suggestive evidence (P<5 × 10-6) for SNPs modifying the thiazide-QT association at 22 loci, including ion transport loci (for example, NELL1, KCNQ3). The biologic plausibility of our suggestive results and simulations demonstrating modest power to detect interaction effects at genome-wide significant levels indicate that larger studies and innovative statistical methods are warranted in future efforts evaluating thiazide-SNP interactions.

Prediction of ventricular tachyarrhythmia in Brugada syndrome by right ventricular outflow tract conduction delay signs.

BACKGROUND: Brugada syndrome (BrS) is an autosomal dominant disease responsible for sudden cardiac death in young individuals without structural anomalies. The most critical part in the management of this channelopathy is identification of high-risk patients, especially asymptomatic subjects. Prior studies have shown that conduction delay in the right ventricular outflow tract (RVOT) is the main mechanism for developing ventricular tachyarrhythmia (VTA) in BrS patients. The aim of this study was to investigate the significance of electrocardiographic RVOT conduction delay parameters as predictors for development of VTA in patients with BrS. METHODS AND RESULTS: We retrospectively analyzed electrocardiograms obtained from 147 BrS patients (43 ± 15 years, 65% men) and assessed the following electrocardiographic parameters: (1) Tzou criteria (V1R > 0.15 mV, V6S > 0.15 mV, and V6S:R > 0.2), (2) prominent S wave in lead I, lead II, and lead III, (3) SII > SIII, and (4) prominent Q wave in lead III as possible predictors of VTA occurrences during follow-up. Prominent SI, SII, SIII, SII > SIII, QIII, and +ve Tzou criteria occurred more frequently in patients who either presented with VTA or developed VTA during the follow-up of 56 (IQR: 40-76) months. SII > SIII has the highest area under the curve for prediction of VTA (AUC: 0.84, sensitivity: 80%, specificity: 89%). Multivariable regression analysis showed that prominent S waves in lead I, SII > SIII and +ve Tzou criteria are independent predictors for VTA in BrS patients. CONCLUSION: Prominent S in lead I, SII > SIII and +ve Tzou criteria can be used as effective signs for predicting VTA in patients with BrS.

Utility of heart rate turbulence and T-wave alternans to assess risk for readmission and cardiac death in hospitalized heart failure patients.

BACKGROUND: Heart failure (HF) patients have a higher risk of recurrent HF and cardiac death, and electrical remodeling is considered to be an important factor for HF progression. The present study aimed to validate the utility of electrocardiogram and Holter monitoring for the risk stratification of HF patients. METHODS: Our study comprised 215 patients (144 males, mean age 62 years) who had been hospitalized due to acute decompensated HF. Electrocardiogram (QRS duration and QTc interval) and 24-hour Holter monitoring (heart rate variability, heart rate turbulence, and T-wave alternans [TWA]) were performed in stable condition before discharge. The clinical characteristics and outcomes were then investigated. RESULTS: During a median follow-up period of 2.7 years, there were 83 (38.6%) cardiac events (rehospitalization due to worsening HF [n = 51] or cardiac death [n = 32]). The patients with cardiac events had a lower turbulence slope (TS) and higher TWA compared to those without cardiac events (TS, 3.0 ± 5.5 ms/RR vs. 5.3 ± 5.6 ms/RR, P = 0.001; TWA, 66.1 ± 19.6 µV vs. 54.7 ± 15.1 µV, P < 0.001). Univariable analysis showed that TS, TWA, QRS duration, and QTc interval were associated with cardiac events (P = 0.004, P < 0.001, P = 0.037, and P = 0.024, respectively), while the multivariable analysis after the adjustment of multiple confounders showed that TS and TWA were independent predictive factors of cardiac events with a hazard ratio of 0.936 and 1.015 (95% confidence interval [CI]: 0.860-0.974, P = 0.006; and 95% CI: 1.003-1.027, P = 0.016), respectively. CONCLUSION: The measurement of TS and TWA is useful for assessing risk for rehospitalization and cardiac death in HF patients.

Change of sensing vector in the subcutaneous ICD during follow-up and after device replacement.

BACKGROUND: The subcutaneous implantable cardioverter defibrillator (S-ICD) has been established as a valuable alternative to transvenous ICD for prevention of sudden cardiac death. The system automatically chooses the optimal sensing vector. However, during follow-up and especially after device replacement we observed a change of the suggested sensing vector in automatic setup. Therefore, we analyzed frequency and reasons of vector change and its impact on inappropriate shocks (IAS). MATERIAL AND METHODS: Between June 2010 and December 2017, a total of 216 patients with S-ICD® were included in this analysis. In all patients sensing vectors at the time of implantation, during follow-up, and after device replacement were investigated. Median follow-up time was 27.3 ± 25.3 months. RESULTS: A change of the initial vector was seen in 77 patients (35.7%). The most frequent reason for vector change was the postoperative setup in supine and erect position in 54 patients (70.1%). In 12 patients (15.5%), the vector was manually changed due to inappropriate sensing and/or therapies. Routine setup during follow-up led to automatic vector change in 10 cases (13.0%). In only 1 patient the vector was manually changed due to oversensing in an exercise treadmill test. In 27 patients, the device was replaced due to battery depletion and in 6 of these patients the sensing vector was changed by the automatic setup. Vector change did not have an impact for inappropriate therapies in the follow-up; only 1 patient received an IAS due to an inadvertent vector change after device replacement. CONCLUSION: In the present study, a significant number of S-ICD® patients had a manual or automatic vector change during follow-up and after device replacement. The study underlines the importance of a thoroughly performed screening and at least two valuable sensing vectors preimplant. Further studies are needed to evaluate the necessity of a routine automatic setup during follow-up.

QRS morphology shift following catheter ablation of idiopathic outflow tract ventricular arrhythmias: Prevalence, mapping features, and ablation outcomes.

INTRODUCTION: In patients with monomorphic idiopathic outflow tract ventricular arrhythmias (OT-VAs), catheter ablation (CA) at the earliest activation site can result in a shift in QRS morphology indicating a change in the activation patterns. This study aimed to investigate the prevalence, mapping features, and ablation outcomes of OT-VAs displaying a QRS morphology shift following CA. METHODS AND RESULTS: We retrospectively analyzed 446 patients with monomorphic OT-VAs. A QRS morphology shift following CA was observed in 17 (4%) patients. Initially, the earliest activation site was within the right ventricular outflow tract (RVOT) in one (6%) patient, the left ventricular outflow tract (LVOT) in 10 (59%) patients (left coronary cusp/right coronary cusp junction in seven patients and LVOT endocardium in three patients), and within the distal coronary venous system in six (35%) patients. The VA was suppressed in all 17 patients, but VA recurrence with a different QRS morphology was observed after a waiting period. The recurrent VA was remapped in all patients and was eliminated targeting the new earliest site in 15 (88%) cases. In 11 of 15 successful cases, the ablation site for the recurrent VA shifted to an anatomical structure distinct from but adjacent to the initial site. In the remaining four patients, the recurrent VA was eliminated within the same anatomical structure. CONCLUSIONS: In patients with idiopathic OT-VAs, a QRS morphology shift following CA can be observed in 4% of the cases. In these cases, detailed remapping is necessary since the successful ablation site for the VAs with altered QRS morphology shifts to different anatomical structures in most patients.

Late potentials abolition reduces ventricular tachycardia recurrence after ablation especially in higher-risk patients with a chronic total occlusion in an infarct-related artery.

INTRODUCTION: Late potentials (LP) abolition is recognized as an effective strategy for substrate ablation of ventricular tachycardia (VT). The presence of a chronic total occlusion in a coronary artery responsible for a previous myocardial infarction (infarct related artery CTO, IRA-CTO) is emerging as a predictor of ventricular arrhythmias and VT recurrence after ablation. We sought to analyze the effects of LP abolition, focusing on the high-risk subgroup of patients with IRA-CTO. METHODS AND RESULTS: This was a single-center, observational study that screened all patients with prior myocardial infarction and clinical VT, referred for VT ablation at San Raffaele Hospital between 2010 and June 2013. Patients were then included in the study if they had a coronary diagnostic angiography (without revascularization) performed during the index hospitalization. The main endpoint was VT recurrence after ablation. Eighty-four patients formed the population of the study. An IRA-CTO was present in 47 patients (56%) and the presence of an IRA-CTO was a predictor of VT recurrence (HR 3.7, P = 0.005). LP were observed in 51 patients and successfully abolished in 38 cases. LP abolition was associated with lower VT recurrence especially among patients with IRA-CTO (24% vs. 65%, P = 0.005). The presence of an IRA-CTO, in combination with no LP abolition, was the strongest predictor of VT recurrence (HR 4.4, P < 0.001). CONCLUSIONS: Late potentials abolition is an effective strategy for substrate ablation of ventricular tachycardia. The additional reduction of VT recurrence achieved with LP abolition on top of noninducibility is especially significant among high-risk patients with IRA-CTO.

The prevalence and characteristics of coexisted atrioventricular nodal reentrant tachycardia and idiopathic left fascicular ventricular tachycardia.

BACKGROUND: Coexistence of idiopathic left fascicular ventricular tachycardia (ILFVT) and atrioventricular nodal reentrant tachycardia (AVNRT) has been rarely reported. OBJECTIVES: The study aimed at elucidating the prevalence of coexisted AVNRT in patients with ILFVT during longitudinal follow-up. The electrophysiological properties and clinical predictors of coexisted ILFVT and AVNRT were investigated. METHODS: From 1999 to 2017, a total of 108 patients (age: 33.7 ± 14.3, 84 male) with ILFVT from one tertiary center were consecutively enrolled. The prevalence of coexisted arrhythmias was explored during a longitudinal follow-up and the electrophysiological parameters from the index procedure were compared. RESULTS: During a mean follow-up period of 106.8 ± 69.5 months, 21 of 108 patients (19.4%) had coexisted AVNRT. The electrophysiological study demonstrated patients with coexisted ILFVT and AVNRT were characterized by more antegrade dual AV node conduction (52.4% vs. 19.5%, P = 0.002; 9.5%), shorter antegrade slow pathway effective refractory period (285.1 ± 34.1 ms vs. 329.2 ± 69.2 ms, P = 0.034), longer retrograde fast pathway effective refractory period (368.9 ± 56.7 ms vs. 312.5 ± 95.2, P = 0.036), and less VA dissociation (19.0% vs. 60.9%, P = 0.001) than those without a coexisted AVNRT. Multivariate logistic analysis showed that presence of antegrade dual AV nodal physiology and retrograde VA conduction could predict a coexisted AVNRT in patients with ILFVT (P = 0.005, OR: 4.80, 95% CI: 1.65-14.37 and P = 0.002, OR: 0.14, 95% CI: 0.04-0.49, respectively). CONCLUSION: There was a high prevalence of coexisted AVNRT in patients with ILFVT during longitudinal follow-up. The presence of antegrade dual AV nodal physiology and retrograde VA conduction can predict the coexisted AVNRT in patients with ILFVT.

A relation between ablation area and outcome of ablation using 28-mm cryoballon ablation: Importance of carina region.

INTRODUCTION: Pulmonary vein isolation (PVI) with wide antral ablation leads to better outcomes in atrial fibrillation ablation therapy, but the ablation area is relatively small during cryoballoon ablation (CBA). The present study tested the hypothesis that wide ablation can lead to better outcomes in CBA. METHODS AND RESULTS: Ninety-six patients with atrial fibrillation were enrolled (paroxysmal 76%, 64.1 ± 11.7 years). All patients underwent preprocedural computed tomography and the PV diameter at left atrial PV junction was measured. PV isolation was performed using a 28-mm CB for 3 minutes with single freezing. Sinus rhythm bipolar voltage amplitude maps with the NavX mapping system were generated after ablation. According to the voltage map, patients were divided into 3 subgroups (68 in the extensive isolation group, 17 in the individual isolation group, and 10 in the incomplete isolation group). Atrial tachyarrhythmias recurred in 9 patients of the extensive isolation group and 6 in the individual isolation group. The rate of 12-month freedom from tachyarrhythmia after a single ablation procedure was 84% (95% confidence interval [C.I.], 72%-91%) in the extensive group and 57% (95% C.I., 28%-78%) in the individual group (P = 0.048). Multiple logistic regression analyses revealed that maximal PV diameter was the only predictor to achieve extensive PVI (odds ratio, 1.57; 95% C.I. 1.08-2.29 P = 0.018). CONCLUSION: Extensive isolation is superior to individual isolation for achieving freedom from atrial arrhythmia in long term follow-up by CBA. Evaluating PV diameter at the left atrial PV junction is essential for applying CBA.

Epicardial ventricular tachycardia in ischemic cardiomyopathy: Prevalence, electrophysiological characteristics, and long-term ablation outcomes.

INTRODUCTION: The characteristics of the epicardial (EPI) substrate responsible for ventricular tachycardia (VT) in ischemic cardiomyopathy (ICM) are undefined, and data on the long-term outcomes of EPI catheter ablation limited. We evaluated the prevalence, electrophysiologic features, and outcomes of catheter ablation of EPI VT in ICM. METHODS AND RESULTS: From December 2010 to June 2013, a total of 13 of 93 (14%) patients with ICM underwent catheter ablation at our institution and had conclusive evidence of critical EPI substrate demonstrated to participate in VT with activation, entrainment and/or pace mapping during sinus rhythm (two other patients underwent EPI mapping but had no optimal ablation targets). The electrophysiologic substrate characteristics and activation/entrainment mapping data were compared with a reference group of ICM patients without evidence of critical EPI substrate (N = 44), defined as a complete procedural success (noninducibility of any VT at programmed stimulation) after endocardial (ENDO)-only ablation. Patients with failed EPI access (N = 2) or history of cardiac surgery (N = 92) were excluded from the study. All 13 patients had evidence of abnormal EPI substrate with fractionated/late/split electrograms and low-bipolar voltage areas. The critical VT ablation sites were all located within the EPI bipolar "dense" scar (<1.0 mV) opposite the ENDO bipolar scar in 77% of cases and extending beyond the ENDO bipolar scar (within the ENDO unipolar low-voltage area) in the remaining patients. Compared with the reference ENDO-only group, patients with EPI VT had a smaller ENDO bipolar scar area, 54.0 (37.1-84) vs 86.7 (55.6-112) cm2 ; P = 0.0159, with a similar extent of ENDO unipolar low voltage. No other substrate characteristics or location differed between the two groups. After 35.2 ± 24.2 months of follow-up, VT-free survival was 73% in patients with EPI VT compared with 66% in the ENDO-only group (log-rank P = 0.56). CONCLUSIONS: The presence of the critical EPI substrate responsible for VT can be demonstrated in at least 14% of patients with ICM. The majority of EPI critical ablation sites are distributed opposite the ENDO bipolar scar area and catheter ablation is effective in achieving long-term arrhythmia control.