PULSE-SMART: Pulse-Based Arrhythmia Discrimination Using a Novel Smartphone Application.

BACKGROUND: Atrial fibrillation (AF) is a common and dangerous rhythm abnormality. Smartphones are increasingly used for mobile health applications by older patients at risk for AF and may be useful for AF screening. OBJECTIVES: To test whether an enhanced smartphone app for AF detection can discriminate between sinus rhythm (SR), AF, premature atrial contractions (PACs), and premature ventricular contractions (PVCs). METHODS: We analyzed two hundred and nineteen 2-minute pulse recordings from 121 participants with AF (n = 98), PACs (n = 15), or PVCs (n = 15) using an iPhone 4S. We obtained pulsatile time series recordings in 91 participants after successful cardioversion to sinus rhythm from preexisting AF. The PULSE-SMART app conducted pulse analysis using 3 methods (Root Mean Square of Successive RR Differences; Shannon Entropy; Poincare plot). We examined the sensitivity, specificity, and predictive accuracy of the app for AF, PAC, and PVC discrimination from sinus rhythm using the 12-lead EKG or 3-lead telemetry as the gold standard. We also administered a brief usability questionnaire to a subgroup (n = 65) of app users. RESULTS: The smartphone-based app demonstrated excellent sensitivity (0.970), specificity (0.935), and accuracy (0.951) for real-time identification of an irregular pulse during AF. The app also showed good accuracy for PAC (0.955) and PVC discrimination (0.960). The vast majority of surveyed app users (83%) reported that it was "useful" and "not complex" to use. CONCLUSION: A smartphone app can accurately discriminate pulse recordings during AF from sinus rhythm, PACs, and PVCs.

Association of Left Atrial Function Index With Late Atrial Fibrillation Recurrence after Catheter Ablation.

INTRODUCTION: Although catheter ablation (CA) for atrial fibrillation (AF) is commonly used to improve symptoms, AF recurrence is common and new tools are needed to better inform patient selection for CA. Left atrial function index (LAFI), an echocardiographic measure of atrial mechanical function, has shown promise as a noninvasive predictor of AF. We hypothesized that LAFI would relate to AF recurrence after CA. METHODS AND RESULTS: All AF patients undergoing index CA were enrolled in a prospective institutional AF Treatment Registry between 2011 and 2014. LAFI was measured post hoc from pre-ablation clinical echocardiographic images in 168 participants. Participants were mostly male (33% female), middle-aged (60 ± 10 years), obese and had paroxysmal AF (64%). Mean LAFI was 25.9 ± 17.6. Over 12 months of follow-up, 78 participants (46%) experienced a late AF recurrence. In logistic regression analyses adjusting for factors known to be associated with AF, lower LAFI remained associated with AF recurrence after CA [OR 0.04 (0.01-0.67), P = 0.02]. LAFI discriminated AF recurrence after CA slightly better than CHADS2 (C-statistic 0.60 LAFI, 0.57 CHADS2). For participants with persistent AF, LAFI performed significantly better than CHADS2 score (C statistic = 0.79 LAFI, 0.56 CHADS2, P = 0.02). CONCLUSION: LAFI, an echocardiographic measure of atrial function, is associated with AF recurrence after CA and has improved ability to discriminate AF recurrence as compared to the CHADS-2 score, especially among persistent AF patients. Since LAFI can be calculated using standard 2D echocardiographic images, it may be a helpful tool for predicting AF recurrence.

Classification and atherosclerosis distribution in patients with left main coronary disease.

OBJECTIVE: The purpose of this investigation was to characterize clinical variables and angiographic distribution of coronary atherosclerosis to classify patients with de novo left main (LM) disease in a real-world population presenting for coronary angiography. BACKGROUND: Limited quantitative and angiographic published data exist that provide detailed quantitative information to classify potential target population for elective LM percutaneous coronary intervention (PCI) and guide development of dedicated LM PCI platforms. METHODS: Medical history and clinical presentation were prospectively collected on 177 consecutive patients with LM stenosis > or =50% by coronary angiography. Blinded quantitative coronary angiography (QCA) was performed on all LM stenoses to classify LM-A (ostial), LM-B (nonostial, non-bifurcation), and LM-C (bifurcation involvement). QCA was performed on the left anterior descending (LAD), left circumflex (LCx), and right coronary arteries (RCA) and branches (> or =2.5 mm) to identify lesions with > or =60% stenosis or occlusion. RESULTS: No differences in baseline clinical history or presentation discriminated the distribution patterns of LM stenosis. QCA revealed 66% of LM stenoses were LM-C. Mean LM reference vessel diameter was 4.65 mm and average lesion length was 11.12 mm. Around 88.7% of patients had at least one lesion > or =60% in a major epicardial artery and 32.2% of patients had RCA chronic total occlusion. Right-to-left coronary collateralization was only identified in patients with obstructive stenosis in the LAD or LCx in addition to the LM stenosis. CONCLUSION: Dedicated LM stent platforms may need to be developed to accommodate larger vessel size and bifurcation distributions. A majority of patients with LM stenosis will require adjunctive epicardial vessel PCI to achieve complete anatomic revascularization.

Burden of Psychosocial and Cognitive Impairment in Patients With Atrial Fibrillation.

BACKGROUND: Impairments in psychosocial status and cognition relate to poor clinical outcomes in patients with atrial fibrillation (AF). However, how often these conditions co-occur and associations between burden of psychosocial and cognitive impairment and quality of life (QoL) have not been systematically examined in patients with AF. METHODS: A total of 218 patients with symptomatic AF were enrolled in a prospective study of AF and psychosocial factors between May 2013 and October 2014 at the University of Massachusetts Medical Center. Cognitive function, depression, and anxiety were assessed at baseline and AF-specific QoL was assessed 6 months after enrollment using validated instruments. Demographic and clinical information were obtained from a structured interview and medical record review. RESULTS: The mean age of the study participants was 63.5 ± 10.2 years, 35% were male, and 81% had paroxysmal AF. Prevalences of impairment in 1, 2, and 3 psychosocial/cognitive domains (eg, depression, anxiety, or cognition) were 75 (34.4%), 51 (23.4%), and 16 (7.3%), respectively. Patients with co-occurring psychosocial/cognitive impairments (eg, >1 domain) were older, more likely to smoke, had less education, and were more likely to have heart failure (all P < 0.05). Compared with participants with no psychosocial/cognitive impairments, AF-specific QoL at 6 months was significantly poorer among participants with baseline impairment in 2 (B = -13.6, 95% CI: -21.7 to -5.4) or 3 (B = -15.1, 95% CI: -28.0 to -2.2) psychosocial/cognitive domains. CONCLUSION: Depression, anxiety, and impaired cognition were common in our cohort of patients with symptomatic AF and often co-occurred. Higher burden of psychosocial/cognitive impairment was associated with poorer AF-specific QoL.

Relation of Atrial Fibrillation in Acute Myocardial Infarction to In-Hospital Complications and Early Hospital Readmission.

Atrial fibrillation (AF) is a common complication of acute myocardial infarction (AMI) and contributes to high rates of in-hospital adverse events. However, there are few contemporary studies examining rates of AF in the contemporary era of AMI or the impact of new-onset AF on key in-hospital and postdischarge outcomes. We examined trends in AF in 6,384 residents of Worcester, Massachusetts, who were hospitalized with confirmed AMI during 7 biennial periods between 1999 and 2011. Multivariate logistic regression analysis was used to examine associations between occurrence of AF and various in-hospital and postdischarge complications. The overall incidence of AF complicating AMI was 10.8%. Rates of new-onset AF increased from 1999 to 2003 (9.8% to 13.2%), and decreased thereafter. In multivariable adjusted models, patients developing new-onset AF after AMI were at a higher risk for in-hospital stroke (odds ratio [OR] 2.5, 95% confidence interval [CI] 1.6 to 4.1), heart failure (OR 2.0, 95% CI 1.7 to 2.4), cardiogenic shock (OR 3.7, 95% CI 2.8 to 4.9), and death (OR 2.3, 95% CI 1.9 to 3.0) than patients without AF. Development of AF during hospitalization for AMI was associated with higher rates of readmission within 30 days after discharge (21.7% vs 16.0%), but no significant difference was noted in early postdischarge 30-day all-cause mortality rates (8.3% vs 5.1%). In conclusion, new-onset AF after AMI is strongly related to in-hospital complications of AMI and higher short-term readmission rates.

Addition of B-Type Natriuretic Peptide to Existing Clinical Risk Scores Enhances Identification of Patients at Risk for Atrial Fibrillation Recurrence After Pulmonary Vein Isolation.

INTRODUCTION: Predicting which patients will be free from atrial fibrillation (AF) after pulmonary vein isolation (PVI) remains challenging. Clinical risk prediction scores show modest ability to identify patients at risk for AF recurrence after PVI. B-type natriuretic peptide (BNP) is associated with risk for incident and recurrent AF but is not currently included in existing AF risk scores. We sought to evaluate the incremental benefit of adding preoperative BNP to existing risk scores for predicting AF recurrence during the 6 months after PVI. METHODS: One hundred sixty-one patients with paroxysmal or persistent AF underwent an index PVI procedure between 2010 and 2013; 77 patients (48%) had late AF recurrence after PVI (>3 months post-PVI) over the 6-month follow-up period. RESULTS: A BNP greater than or equal to 100 pg/dL (P=0.01) and AF recurrence within 3 months after PVI (P<0.001) were associated with late AF recurrence in multivariate analyses. Addition of BNP to existing clinical risk scores significantly improved the areas under the curve for each score, with an integrated discrimination improvement of 0.08 (P=0.001) and a net reclassification improvement of 60% (P=0.001) for all risk scores. CONCLUSIONS: Circulating BNP levels are independently associated with late AF recurrence after PVI. Inclusion of BNP significantly improves the discriminative ability of CHADS2, CHA2DS2-VASc, R2CHADS2, and the HATCH score in predicting clinically significant, late AF recurrence after PVI and should be incorporated in decision-making algorithms for management of AF. B-R2CHADS2 is the best score model for prediction of late AF recurrence.

A 30-year perspective (1975-2005) into the changing landscape of patients hospitalized with initial acute myocardial infarction: Worcester Heart Attack Study.

BACKGROUND: The effects of lifestyle changes and evolving treatment practices on coronary disease incidence rates, demographic and clinical profile, and the short-term outcomes of patients hospitalized with acute myocardial infarction have not been well characterized. The purpose of this study was to examine multidecade-long trends (1975-2005) in the incidence rates, demographic and clinical characteristics, treatment practices, and hospital outcomes of patients hospitalized with an initial acute myocardial infarction from a population-based perspective. METHODS AND RESULTS: Residents of the Worcester, Mass, metropolitan area (median age, 37 years; 89% white) hospitalized with an initial acute myocardial infarction (n=8898) at all greater-Worcester medical centers during 15 annual periods between 1975 and 2005 comprised the sample of interest. The incidence rates of initial acute myocardial infarction were lower in 2005 (209 of 100,000 population) than in 1975 (277 of 100,000), although these trends varied inconsistently over time. Patients hospitalized during the most recent study years were significantly older (mean age, 64 years in 1975; 71 years in 2005), more likely to be women (38% in 1975; 48% in 2005), and have a greater prevalence of comorbidities. Hospitalized patients were increasingly more likely to receive effective cardiac medications and coronary interventional procedures for the period under investigation. Hospital survival rates improved significantly over time (81% survived in 1975; 91% survived in 2005), although varying trends were observed in the occurrence of clinically important complications. CONCLUSIONS: The results of this community-wide investigation provide insight into the changing magnitude, characteristics, management practices, and outcomes of patients hospitalized with a first myocardial infarction.

Age-based differences of percutaneous coronary intervention in the drug-eluting stent era.

INTRODUCTION: Limited data are available on contemporary percutaneous coronary intervention (PCI) practice patterns and outcomes in elderly patients. The objective of this study was to evaluate "real-world" PCI in elderly and nonelderly patients during the first year of availability of drug-eluting stents (DES) in the United States market (May 1, 2003-April 30, 2004). METHODS: One thousand one hundred sixty-six consecutive patients (272 elderly [age > or =75 years] and 894 nonelderly [age <75 years]) having PCI for de novo coronary artery disease (CAD) at Dartmouth-Hitchcock Medical Center were included in this study. Primary outcome measures of this study were in-hospital major adverse cardiac events (MACE-death, new MI, urgent revascularization). Secondary end points included acute renal failure, respiratory failure, and vascular complications. RESULTS: Elderly patients had higher MACE (8.5% vs 1.5%, P < or = 0.001), unadjusted in-hospital mortality (7.4% vs 0.8%, P < or = 0.001), in-hospital cardiac arrest (1.5% vs 0.3%, P = 0.03), requirements for assisted blood pressure support (13.2% vs 7.0%, P = 0.0001), respiratory failure (2.2% vs 0.9%, P = 0.08), acute renal failure (2.9% vs 0.8%, P = 0.005), and vascular complications (10.3% vs 5.5%, P = 0.005) than their nonelderly counterparts. Higher MACE rates persisted in the elderly despite correction for baseline differences using multivariate regression modeling. CONCLUSIONS: Advanced age remains a predictor of adverse outcomes attending PCI even in the contemporary era in which DES are available. This study highlights the need for further progress and investigation to optimize outcomes of PCI in the elderly.