Wireless CardioS framework for continuous ECG acquisition.

A first-level textile-based electrocardiogram (ECG) monitoring system referred to as "CardioS" (cardiac sensor) for continuous health monitoring applications is proposed in this study to address the demand for resource-constrained environments. and the signal quality assessment of a wireless CardioS was studied. The CardioS consists of a Lead-I ECG signal recorded wirelessly using silver-plated nylon woven (Ag-NyW) dry textile electrodes to compare the results of wired wearable Ag-NyW textile electrode-based ECG acquisition system and CardioS. The effect of prolonged usage of Ag-NyW dry electrodes on electrode impedance was tested in the current work. In addition, electrode half-cell potential was measured to validate the range of Ag-NyW dry electrodes for ECG signal acquisition. Further, the quality of signals recorded by the proposed wireless CardioS framework was evaluated and compared with clinical disposable (Ag-AgCl Gel) electrodes. The signal quality was assessed in terms of mean magnitude coherence spectra, signal cross-correlation, signal-to-noise-band ratio (Sband/Nband), crest factor, low and high band powers and power spectral density. The experimental results showed that the impedance was increased by 2.5-54.6% after six weeks of continuous usage. This increased impedance was less than 1 MΩ/cm2, as reported in the literature. The half-cell potential of the Ag-NyW textile electrode obtained was 80 mV, sufficient to acquire the ECG signal from the human body. All the fidelity parameters measured by Ag-NyW textile electrodes were correlated with standard disposable electrodes. The cardiologists validated all the measurements and confirmed that the proposed framework exhibited good performance for ECG signal acquisition from the five healthy subjects. As a result of its low-cost architecture, the proposed CardioS framework can be used in resource-constrained environments for ECG monitoring.

Use of Oral Empagliflozin to Obtain Optimal Blood Sugar Levels for Conducting 18 F-FDG PET-CT in Patients with Hyperglycemia-A Pilot Study.

Background Flourine-18 fluorodeoxyglucose positron emission tomography-computed tomography ( 18 F-FDG PET-CT) is a well-established imaging modality for the evaluation of patients with oncological and nononcological conditions. The underlying principle of imaging is the preferentially increased glucose consumption by cancer cells, due to overexpression of glucose type 1 receptors that are insulin independent. Thus, one of the factors that leads to decreased sensitivity of an 18 F-FDG PET-CT is elevated blood sugar levels, leading to decreased glucose uptake by cancer cells due to competitive inhibition. A significant percentage of patients scheduled for PET-CT scan has diabetes mellitus type II as a comorbid condition and often has elevated random blood sugar (RBS) precluding an upfront PET-CT evaluation. Such cases must be rescheduled. This causes delay in the evaluation and management of such patients. Empagliflozin is a novel sodium glucose type 2 inhibitor that prevents tubular reabsorption of glucose and increases renal glycosuria resulting in decreased blood sugar. This drug does not cause significant hypoglycemia or increase endogenous insulin secretion. This study was undertaken to evaluate a potential role for empagliflozin in facilitating optimal blood sugar control in patients with hyperglycemia on the day of the scheduled PET scan. Methods This is an interventional prospective study and patients detected to have RBS more than 200 mg/dL on the day of the scheduled scan were included in the study. The patients were administered two tablets of 10 mg empagliflozin and kept under observation. Samples for RBS were taken at approximately 2nd and 4th hour post administration by bedside method. These patients underwent scan on the same day after adequate sugar control and when an RBS of less than 200 mg/dL was achieved. The primary outcome studied was change in RBS values in the patient cohort and evaluation of PET SUV (standardized uptake value) compared with the rest of the patients scheduled on the same day. Secondary outcome was assessment of any side effects in the patients. Results Total of 10 patients were found to have elevated blood sugar (RBS > 200 mg/dL; irrespective of being on medication) and did not meet the evaluation criteria for a PET-CT scan on the scheduled day. Following administration of the drug, all 10 patients were able to attain blood sugar levels and fulfill the criteria for undergoing a PET-CT scan. No obvious side effect was noted in any of the patient. The SUV values of the patient cohort were comparable with the rest of the patient scanned on the day. Conclusion In this pilot study, 20 mg of empagliflozin (2 tablets of 10 mg) appears to be a safe and effective method for achieving optimal decrease in the RBS without causing hypoglycemia or hyperinsulinemia. It can be safely employed in the subset of population with RBS between 201 and 300 mg/dL to adequately bring the sugar levels at acceptable levels RBS less than 200 mg/dl and fulfill the FDG PET-CT criteria as per European Association of Nuclear Medicine (EANM) norms.

A Signal Processing Framework for the Detection of Abnormal Cardiac Episodes.

MOTIVATION: Cardiologists rely on the long duration Holter electrocardiogram (ECG) recordings in general for assessment of abnormal episodes and such process found to be tedious and time consuming. An automatic abnormal cardiac episode detection algorithm is the need of the hour that needs to be optimized to reduce the manual burden. OBJECTIVE: The current study presents a signal processing framework with a cross-database to detect abnormal episodes in long-term ECG signals. METHODOLOGY: The data was pre-processed to remove power line interference and baseline drift using basis pursuit sparsely decomposed tunable-Q wavelet transform (BPSD-TQWT). A total of 44 features of time domain, frequency domain, and time-frequency domain characteristics were extracted from the ECG signal. This proposed work tested classification performance with support vector machine (SVM), K-nearest neighbour (KNN), decision tree, naïve Bayes, the nearest mean classifier, and the nearest root mean square classifiers. The trained models with open-source data were used to predict the abnormal episodes from the proprietary database and vice versa. Finally, the performance was analysed via recall rate, specificity, precision, F1-score, and accuracy. RESULTS: Among six classification models, SVM performed best. With an open-source database, the SVM model achieved 95.01% accuracy, and detected the abnormal episodes from proprietary database with an accuracy of 99.31%. In addition, with the proprietary database SVM model classified the normal-abnormal cardiac episodes with an accuracy of 99.89% and detected the abnormal episodes from proprietary database with an accuracy of 92.51%. CONCLUSION: When the performance results were compared with the literature, it was observed that the proposed framework performed well. As a result, the proposed framework could be used in an autonomous diagnosis system.

Effect of Indian Music as an Auditory Stimulus on Physiological Measures of Stress, Anxiety, Cardiovascular and Autonomic Responses in Humans-A Randomized Controlled Trial.

Among the different anthropogenic stimuli humans are exposed to, the psychological and cardiovascular effects of auditory stimuli are less understood. This study aims to explore the possible range of change after a single session of auditory stimulation with three different 'Modes' of musical stimuli (MS) on anxiety, biomarkers of stress, and cardiovascular parameters among healthy young individuals. In this randomized control trial, 140 healthy young adults, aged 18−30 years, were randomly assigned to three MS groups (Mode/Raga Miyan ki Todi, Malkauns, and Puriya) and one control group (natural sounds). The outcome measurements of the State-Trait Anxiety Inventory, salivary alpha-amylase (sAA), salivary cortisol (sCort), blood pressure, and heart rate variability (HRV) were collected at three time points: before (M1), during (M2), and after the intervention (M3). State anxiety was reduced significantly with raga Puriya (p = 0.018), followed by raga Malkauns and raga Miyan Ki Todi. All the groups showed a significant reduction in sAA. Raga Miyan ki Todi and Puriya caused an arousal effect (as evidenced by HRV) during the intervention and significant relaxation after the intervention (both p < 0.005). Raga Malkauns and the control group had a sustained rise in parasympathetic activity over 30 min. Future studies should try to use other modes and features to develop a better scientific foundation for the use of Indian music in medicine.

External Cardiac Loop Recorders: Functionalities, Diagnostic Efficacy, Challenges and Opportunities.

According to the World Health Organization's (WHO) report of 2016, cardiovascular diseases (CVDs) accounted for mortality of an estimated 17.9 million people globally. Of these deaths, 85% were due to myocardial infarction and stroke. Further, the pre-dominant atrial fibrillation (AF) arrhythmia has been the most suspected underlying cause of transient ischemic attack or stroke. Thus, the etiologies of early symptoms like syncope and palpitations in patients needs to be evaluated by employing proper diagnostic tests to make early treatment decisions. The most widely referred 24 to 48 hour Holter electrocardiographic (ECG) monitoring tests have not been proved to be much effective in recognizing infrequent intermittent arrhythmic episodes. These drawbacks have led to the development of long-term ambulatory ECG (AECG) monitoring devices. This review reports the state-of-the-art existing AECG monitoring devices and their role of long-term ECG recording in patients suspected with cardiac syncope and palpitations to understand the underlying arrhythmic cause, as well as in the diagnosis and management of AF. Primarily, the utility and diagnostic yield of external cardiac recorders or event loop recorders (ELRs) in capturing the symptom-rhythm correlation which constitutes a clinically useful recordings of heart's electrical activity during infrequent arrhythmic conditions was critically reviewed. Furthermore, a brief case study on challenges involved in clinical data acquisition at a cardiac care unit using ambulatory external monitoring device has been presented. Finally, improvements in design engineering and algorithmic developments to enhance the diagnostic yield and usability of ELRs in clinical settings have been proposed.

Treatment of Class II division I malocclusion having severe crowding, proclination with noncomplaint fixed functional appliance therapy, and frictionless mechanics.

Our Objective was to treat a patient having proclined, protruded teeth along with a Class II Skeletal malocclusion. 0.022 × 0.028 inch MBT Brackets were placed, and leveling alignment was commenced. Individual canine retraction was carried out in both arches, followed by retraction of the incisors in the upper arch with a Burrstone's T Loop. E2Z Forsus fatigue resistance appliance was given for the correction of Class II malocclusion. Proclination, protrusion, and crowding were corrected along with Class II Skeletal base. Individual canine retraction along with frictionless mechanics and noncompliant functional correction has sufficient potential to prevent anchor loss and correct a Class II skeletal base.

His bundle pacing-is it the final frontier of physiological pacing ?-A single centre experience from the Indian sub-Continent.

BACKGROUND: Long term right ventricular pacing can have deleterious effects on left ventricular (LV) function. His bundle pacing (HBP), a novel procedure can probably circumvent this setback. We investigated if (1) HBP is associated with pacing induced LV dysfunction by using LV global longitudinal strain (GLS) and (2) intermediate term performance of the Select Secure (3830) lead in the His bundle location. This report is probably the first on HBP in the Indian population. METHODS: 61 patients, with normal LV ejection fraction (EF) with a guideline based indication for permanent pacing underwent a HBP pacemaker implantation using the His Select Secure 3830 lead; with lead guided mapping for locating the His bundle. The patients underwent GLS assessment; evaluation of the His lead parameters - sensing, impedance and capture thresholds immediately after implantation and at 6 months in addition to the standard follow up. RESULTS: At 6 month follow up, the average GLS did not show significant variation from baseline in patients requiring ventricular pacing more than 40% and was similar, irrespective of selective or non selective His bundle pacing. All the patients had stable pacemaker parameters - with little change in capture threshold, lead impedance or sensing of the His bundle lead - implying electrical and mechanical stability on intermediate term follow-up. CONCLUSION: HBP is a feasible procedure in the hands of an experienced operator, with stable lead performance. It does not appear to be associated with pacing mediated left ventricular dysfunction at intermediate term follow up. It should probably become the default method of permanent pacing.

Acute pulmonary thromboembolism: Epidemiology, predictors, and long-term outcome - A single center experience.

INTRODUCTION: Acute pulmonary thromboembolism (PTE) is a life-threatening disease. Mortality in PTE still remains very high in spite of progress in diagnostic tools. Mortality rate is about 30% in patients with unrecognized acute PTE. METHODS: It is a single center observational study of 31 consecutive patients who were hospitalized in the Department of Cardiology at MS Ramaiah Memorial hospital between January 1, 2010 and June 2015. All the patients confirmed with diagnosis of acute PTE by CT scan (either HRCT or CTPA) were included in the study. Following relevant investigations chosen patients were risk stratified as per standard guidelines into massive, sub massive or low risk and treated accordingly. The included patients were followed up for a period of 1 year with 2D-echocardiogram and other relevant investigations for comparison to assess improvement. Mortality due to either acute PTE or other causes was noted in the study. RESULTS: Of the 31 patients enrolled in our study, 71% (n=22) of the patients belonged to the age range 20-50 years with those in the age group 31-40 years comprising 39% (n=12) of the total. Elderly people over 65 years of age comprised only 19% (n=6) of the total number of patients. Dyslipidemia, prolonged immobilization, deep vein thrombosis, post-operative state, malignancy and post-partum period were the commonly reported risk factors. We thrombolysed a total of 18 (58%) patients with massive and submassive PTE, of which 12 (39%) received tenecteplase and 6 patients received streptokinase (19%). Three (9%) patients required repeat thrombolysis with streptokinase due to failed thrombolytic therapy with tenecteplase. CONCLUSIONS: Our study reported higher incidence of acute PTE in the middle age group population. Prevalence of dyslipidemia was high in this cohort of patients studied although the exact association of it in APE could not be determined. Thrombolytic therapy can be considered for patients with both massive and submassive pulmonary thromboembolism. Repeat thrombolysis can be considered in case one thrombolytic agent failed to give the desirable results.

Antianginal Efficacy and Tolerability of Ranolazine as an Add-on Drug to Concomitant Medications Primarily Metoprolol in Chronic Stable Angina Patients: A Prospective, Open-Label Study.

OBJECTIVE: To evaluate the efficacy and tolerability of ranolazine as an add-on drug in chronic stable angina patients and the impact of ranolazine on the quality of life in chronic stable angina patients receiving other antianginal medications. MATERIALS AND METHODS: It was a prospective, open-label, hospital-based study involving 144 patients with chronic stable angina. First group received either metoprolol 12.5 or 25 mg/day or other antianginal medications; if the symptoms persist, the dose of metoprolol was increased to 50 mg/day, and to the second group, ranolazine 500 mg BD or 1 g OD was added along with metoprolol or others if the anginal attacks were not subsiding. The patients were followed up to 6 months with electrocardiography, treadmill test, and quality of life questionnaire. Adverse events were recorded at each visit during the study. RESULTS: There was a statistically significant reduction in weekly anginal frequency (P < 0.001) and improvement in an exercise tolerance in both the groups, but more in the ranolazine group. Adverse events reported were mild, infrequent. CONCLUSION: Ranolazine is could be used as an add-on drug in chronic angina patients not improved with metoprolol or antianginal medications.

Cardiovascular risk profile and management of atrial fibrillation in India: Real world data from RealiseAF survey.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia with high risk for many cardiovascular (CV) complications. Adherence to recommended management guidelines is important to avoid complications. In India, there is little knowledge on how AF is managed in real world. METHODS: This is a cross-sectional study of patients in India enrolled in RealiseAF survey between February 2010 and March 2010 with a diagnosis of AF within the last 12 months. RESULTS: From 15 centers, 301 patients {mean age 59.9 years (14.4); 52.5% males} were recruited. AF was controlled in 50% of patients with 77 (26.7%) in sinus rhythm and 67 (23.3%) with heart rate <80beats/min. Hypertension (50.8%), valvular heart disease (40.7%), heart failure (25.9%), and diabetes (20.4%) were the most common underlying CV diseases. Increased risk for stroke (CHADS2 score≥2) was present in 36.6%. Most of the patients (85%) were symptomatic. AF was paroxysmal, persistent, and permanent in 28.7%, 22.7%, and 34.3% respectively. In 14%, AF was diagnosed as first episode. Forty-six percent of patients had rate control, 35.2% rhythm control, 0.3% both strategies, and 18.4% received no therapy for AF before the visit. At the end of the visit, adoption to rate control strategy increased to 52.3% and patients with no therapy decreased to 7%. CONCLUSION: AF in India is not adequately controlled. Concomitant CV risk factors and risk of stroke are high. The study underscores the need for improved adoption of guideline-directed management for optimal control of AF and reducing the risk of stroke.

Progressive hemifacial atrophy with ciliary body atrophy and ocular hypotony.

Progressive hemifacial atrophy (PHA) is a disease of unknown etiology affecting one-half of the face. Ocular involvement is uncommon. Atrophy of iris is rare, with only a few cases of partial atrophy being reported in the literature. We report a case of total atrophy of iris and ciliary body with associated ocular hypotony in a 16-year-old girl with PHA. We believe this is the first reported case of complete atrophy of iris and ciliary body in PHA. Ocular hypotony in PHA was thought to be due to intra-ocular inflammation. However in our case it appears to be secondary to severe atrophy of the ciliary body.

Randomized, double-blind, phase I/II study of intravenous allogeneic mesenchymal stromal cells in acute myocardial infarction.

BACKGROUND AIMS: Cell therapy is promising as an exploratory cardiovascular therapy. We have recently developed an investigational new drug named Stempeucel (bone marrow-derived allogeneic mesenchymal stromal cells) for patients with acute myocardial infarction (AMI) with ST-segment elevation. A phase I/II randomized, double-blind, single-dose study was conducted to assess the safety and efficacy of intravenous administration of Stempeucel versus placebo (multiple electrolytes injection). METHODS: Twenty patients who had undergone percutaneous coronary intervention for AMI were randomly assigned (1:1) to receive intravenous Stempeucel or placebo and were followed for 2 years. RESULTS: The number of treatment-emergent adverse events observed were 18 and 21 in the Stempeucel and placebo groups, respectively. None of the adverse events were related to Stempeucel according to the investigators and independent data safety monitoring board. There was no serious adverse event in the Stempeucel group and there were three serious adverse events in the placebo group, of which one had a fatal outcome. Ejection fraction determined by use of echocardiography showed improvement in both Stempeucel (43.06% to 47.80%) and placebo (43.44% to 45.33%) groups at 6 months (P = 0.26). Perfusion scores measured by use of single-photon emission tomography and infarct volume measured by use of magnetic resonance imaging showed no significant differences between the two groups at 6 months. CONCLUSIONS: This study showed that Stempeucel was safe and well tolerated when administered intravenously in AMI patients 2 days after percutaneous coronary intervention. The optimal dose and route of administration needs further evaluation in larger clinical trials (http://clinicaltrials.gov/show/NCT00883727).

A comparative evaluation of prasugrel and clopidogrel in patients with acute coronary syndrome undergoing percutaneous coronary intervention.

OBJECTIVE: Primary objective of this study was to compare the efficacy of Prasugrel vs. Clopidogrel in the patients with acute coronary syndromes (ACS) undergoing percutaneous coronary intervention (PCI) by measuring inhibition of platelet aggregation after loading and maintenance dose of both the drugs. The patients were also assessed for safety of the drugs. METHODS: This was a randomised, double-blind, double-dummy, comparative, multicentric clinical trial in patients with acute coronary syndrome (unstable angina, non-ST elevation MI and ST elevation MI) undergoing PCI. The patients were randomly assigned to receive prasugrel (loading dose of 60 mg followed by maintenance dose of 10-mg once daily) or clopidogrel (loading dose of 300 mg followed by maintenance dose of 75 mg once daily) for a period of 12 weeks. All the patients were co-prescribed aspirin 325 mg with both the drugs. The primary efficacy end point in this study was percentage inhibition of ADP induced platelet aggregation (IPA) at 4 +/- 1 hours after the loading dose and at 30 +/- 3 days during maintenance treatment. The platelet aggregation of both the drugs was measured by whole blood aggregometer using 10 mmol of ADP as an aggregant. Though this study was not powered to see the difference in clinical efficacy parameters, the patients were observed for the incidence of nonfatal MI, nonfatal stroke, re-hospitalization, death, or need for urgent revascularization due to a cardiac ischemic event at days 30 and 90 during the study. The safety of study drugs were evaluated by incidence of major bleeding, reported adverse drug reaction and alterations of any laboratory parameters. RESULT: A total of 220 patients were enrolled at 11 centres across India. Ten patients were given the loading dose of prasugrel or clopidogrel but did not underwent PCI due to change in investigator's decision to go for PCI. Out of 210 eligible patients, 21 patients were discontinued during the study. 157 patients were evaluated for platelet inhibition after loading dose at 4 hours and 150 patients at day 30 during maintenance phase of antiplalelet therapy. The investigators could not perform this test in remaining patients due to urgency and criticality of the patients. 189 patients were observed for the incidence of nonfatal MI, nonfatal stroke, rehospitalisation, urgent revascularisation or death due to a cardiac ischemic event. All eligible patients who received at least a loading dose were evalauted for safety. In prasugrel group, 85 and 77 patients were evaluated for IPA at 4 hours and day 30 respectively whereas in clopdogrel group 72 and 73 patients were tested for IPA at 4 hours and at 30 days. Patients in prasugrel group have demonstrated significantly higher inhibition of platelets as compared to clopidogrel group (82.5% vs 71.1%) at 4 hours and at 30 days (84.1% vs 67.4%). The difference in inhibition of platelets between prasugrel and clopidogrel after loading dose and maintenenace dose was statistically significant (p < or = 0.01). The patients were also evaluated for drug hyporesponsiveness to antiplatelet therapy if IPA was < 20% at day 30 from the baseline. More patients on prasugrel have shown response to antiplatlet therapy than on clopidogrel (97.4% vs 87.6%). The difference between the two groups was statistically significant (p < 0.05). There was no difference observed during the study in the incidence of nonfatal MI, nonfatal stroke, death, rehospitalisation or need for urgent revascularisation due to a cardiac event between prasugrel and clopidogrel. Both the drugs were found to be to be well tolerated and have comparable safety profile. CONCLUSION: This study suggests that prasugrel is more effective than clopidogrel as an anti platelet drug as evident by inhibition of platelet aggregation. More patients on clopidogrel are likely to have poor response to therapy as compared to prasugrel. Both the drugs were well tolerated and have comparable safety profile.

Clinical phenotype and linkage analysis of the congenital fibrosis of the extraocular muscles in an Indian family.

PURPOSE: To describe the clinical phenotype and linkage analysis of the congenital fibrosis of the extraocular muscles (CFEOM) in an Indian family. METHODS: Individuals were examined and their peripheral blood samples were withdrawn for genetic analysis. The disorder was tested for linkage to two known autosomal dominant CFEOM loci on chromosome 12p11.2-q12 (CFEOM1) and chromosome 16q24 (CFEOM3) using microsatellite markers. RESULTS: Nine individuals including seven affecteds participated in the study. All seven affecteds had a classic form of CFEOM which included congenital bilateral ptosis, hypotropia, and chin elevation. The disorder segregated as an autosomal dominant trait in this family. The maximum simulated lod score in this family was 2.02. Linkage to CFEOM3 was excluded (Z<-2.00), whereas analysis of chromosome 12 markers was positive. The maximum observed two-point lod score was 1.8 (given the size and structure of the family) at theta=0 with marker D12S345. Markers D12S61, D12S1631, D12S87, D12S345, D12S59, D12S1048, and D12S1668 cosegregated with the disease locus in all affecteds. Haplotype analysis showed that the candidate region spanned the centromere. CONCLUSIONS: The present data showed a classic CFEOM phenotype in an Indian family. The family's phenotype is consistent with linkage to CFEOM1 locus on chromosome 12p11.2-q12.

Evaluation of the predictors of choledocholithiasis: comparative analysis of clinical, biochemical, radiological, radionuclear, and intraoperative parameters.

This prospective study was performed to assess the predictive ability of the various indicators of common bile duct (CBD) calculi, individually or in combination, by analyzing 88 patients with gallstone disease. The patients were classified into two groups according to the presence of 10 predefined criteria. Of 53 patients with one or more risk factors (group 2), 26 harbored CBD calculi; none of 35 patients with no risk factors (group 1) had CBD stones. Jaundice correlated best, with a sensitivity of 69%; and pancreatitis had the lowest sensitivity (12%). Elevated serum bilirubin and alkaline phosphatase levels correlated better than liver enzymes and serum amylase. The sensitivity and negative predictive value of cholescintigraphy scanning for diagnosing CBD calculi were better than those of ultrasonography, the sensitivity being 84% versus 50% and the negative predictive value 95% versus 82%. Endoscopic retrograde cholangiopancreaticography was successful in 94% of the patients, and CBD calculi were diagnosed in 74%. Moreover, peroperative cholangiography was 100% sensitive with no false-positive results. Ultimately, a palpable stone at surgery was the best predictor. When all the criteria were analyzed, it was found that as the number of criteria increased so did the percentage of patients harboring CBD calculi.

Pulmonary vein morphology in patients with paroxysmal atrial fibrillation initiated by ectopic beats originating from the pulmonary veins: implications for catheter ablation.

BACKGROUND: Successful ablation of ectopic beats originating from the pulmonary veins (PV) could eliminate paroxysmal atrial fibrillation (PAF). However, information about the structure of the PV in patients with PAF that is initiated by PV ectopic beats has not been reported. METHODS AND RESULTS: We studied the morphology of the PVs and measured their diameters in 3 groups of patients. Group I included 52 patients (aged 66+/-14 years; 44 men) with focal atrial fibrillation (AF) from the PVs. Group II included 8 patients (aged 50+/-10 years; 3 men) with focal AF from the superior vena cava or cristal terminalis. Group III included 23 control patients (aged 55+/-16 years; 17 men). Of the control patients, 11 had AV node and 12 had AV reentrant tachycardia. After an atrial transseptal procedure, selective PV angiography using a biplane system with a right anterior oblique view of 30 degrees, a left anterior oblique view of 60 degrees, and a cranial angle of 20 degrees was performed. The ostial and proximal portions of the right and left superior PVs (RSPV and LSPV) were significantly dilated in group I patients compared with those in groups II and III. Furthermore, the ostia of the RSPV and LSPV were significantly dilated in group II compared with group III patients. However, the mean diameters of the inferior PVs were similar between the 3 groups. Comparisons of the individual PV diameters among the 3 subgroups of group I (which was divided according to where the ectopic focus was located) showed nonselective dilatation of the PV. CONCLUSIONS: Nonspecific dilatation of the ostia and proximal portion of superior PVs were found in patients with PAF initiated by ectopic beats from the superior PVs.

Initiation of atrial fibrillation by ectopic beats originating from the pulmonary veins: electrophysiological characteristics, pharmacological responses, and effects of radiofrequency ablation.

BACKGROUND: Atrial fibrillation (AF) can be initiated by ectopic beats originating from the atrial or great venous tissues. This study investigated the anatomic characteristics and electrophysiological properties of pulmonary veins (PVs), as well as the possible mechanisms and response to drugs of ectopic foci, and assessed the effects of radiofrequency (RF) ablation on AF initiated by ectopic beats originating from PVs. METHODS AND RESULTS: Seventy-nine patients with frequent episodes of paroxysmal AF and 10 control patients were included. Distal PVs showed the shortest effective refractory periods (ERPs), and right superior PVs showed a higher incidence of intra-PV conduction block than left superior PVs. Superior and left PVs had longer myocardial sleeves than inferior and right PVs, respectively. These electrophysiological characteristics were similar between AF and control patients. Propranolol, verapamil, and procainamide suppressed ectopic beats that originated from the PVs. Of 116 ectopic foci that initiated AF, 103 (88.8%) originated from PVs. A mean of 7+/-3 RF applications completely eliminated 110 ectopic foci (94.8%). During the 6+/-2-month follow-up period, 68 patients (86. 1%) were free of AF without any antiarrhythmic drugs. Follow-up transesophageal echocardiogram showed 42.4% of ablated PVs had focal stenosis. One patient had mild exertional dyspnea after ablation, but it resolved 3 months later; 1 patient had onset of mild exertional dyspnea 5 months after ablation. CONCLUSIONS: Electrophysiological characteristics of PVs are different from those in the atria. Ectopic beats from PVs can initiate AF, and beta-adrenergic receptor blocker, calcium channel blockers, and sodium channel blockers can suppress these ectopic beats. Careful mapping and elimination of these ectopic foci can cure paroxysmal AF.

Right atrial focal atrial fibrillation: electrophysiologic characteristics and radiofrequency catheter ablation.

INTRODUCTION: Information about focal atrial fibrillation (AF) originating from the right atrium has not been well described. The purposes of this study were to demonstrate the electrophysiologic characteristics and radiofrequency catheter ablation in patients who had right atrial focal AF. METHODS AND RESULTS: From January 1996 to September 1998, 172 patients with clinically documented attacks of paroxysmal AF were referred to this institution for electrophysiologic study and/or radiofrequency catheter ablation. Anterior free wall, crista terminalis, and right and left superior pulmonary veins were mapped simultaneously. Eight patients (4.7%) had right atrial focal AF, consistent activation sequence, irregular fibrillation interval (mean fibrillation interval: 164 +/- 11 msec), and episodes of exit block from the initiating foci observed. The presumed ablation site was chosen on the basis of the earliest bipolar activity relative to an atrial electrogram reference during the initiation of AF. After application of 2 +/- 1 radiofrequency pulses, AF was eliminated without recurrence during the follow-up period (mean: 14 +/- 8 months; range: 3 to 25). Twenty-four-hour Holter monitoring showed that the number of atrial premature beats decreased significantly at the 3-month follow-up (4,216 +/- 411 vs 135 +/- 14 beats/day). CONCLUSION: Right atrial focal AF is one subgroup of focal AF, and it can be cured by radiofrequency catheter ablation.

Double multielectrode mapping catheters facilitate radiofrequency catheter ablation of focal atrial fibrillation originating from pulmonary veins.

INTRODUCTION: Several reports have demonstrated that focal atrial fibrillation (AF) may arise from pulmonary veins (PVs). The purpose of this study was to investigate the safety and efficacy of using double multielectrode mapping catheters in ablation of focal AF. METHODS AND RESULTS: Forty-two patients (30 men, 12 women, age 65+/-14 years) with frequent attacks of paroxysmal AF were referred for catheter ablation. After atrial transseptal procedure, two long sheaths were put into the left atrium. Two decapolar catheters were put into the right superior PV (RSPV) and left superior PV (LSPV), or inferior PVs if necessary, guided by pulmonary venography. All the patients had spontaneous initiation of AF either during baseline (2 patients), after isoproterenol infusion (8 patients) or high-dose adenosine (2 patients), after short duration burst pacing under isoproterenol (14 patients), or after cardioversion of pacing-induced AF (16 patients). The trigger points of AF were from the LSPV (12 patients), RSPV (8 patients), and both superior PVs (19 patients). The trigger points from PVs (total 61 points) were 18 (30%) in the ostium of PVs and 43 inside the PVs (9 to 40 mm). After 6+/-3 applications of radiofrequency energy, 57 of 61 triggers were completely eliminated, and the other 4 triggers were partially eliminated. During a follow-up period of 8+/-2 months, 37 patients (88%) were free of symptomatic AF without any antiarrhythmic drugs. Twenty patients received a transesophageal echocardiogram, and 19 showed small atrial septal defects (2.8+/-1.2 mm) with trivial shunt. Fifteen defects closed spontaneously 1 month later. CONCLUSION: The technique using double multielectrode mapping catheters is a relatively safe and highly effective method for mapping and ablation of focal AF originating from PVs.