Colleen Johnson

Electrocardiographic comparison of ventricular arrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy and right ventricular outflow tract tachycardia.

OBJECTIVES The purpose of this study was to evaluate whether electrocardiographic characteristics of ventricular arrhythmias distinguish patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) from those with right ventricular outflow tract tachycardia (RVOT-VT). BACKGROUND Ventricular arrhythmias in RVOT-VT and ARVD/C-VT patients can share a left bundle branch block/inferior axis morphology. METHODS We compared the electrocardiographic morphology of ventricular tachycardia or premature ventricular contractions with left bundle branch block/inferior axis pattern in 16 ARVD/C patients with that in 42 RVOT-VT patients. RESULTS ARVD/C patients had a significantly longer mean QRS duration in lead I (150 ± 31 ms vs. 123 ± 34 ms, p = 0.006), more often exhibited a precordial transition in lead V(6) (3 of 17 [18%] vs. 0 of 42 [0%] with RVOT-VT, p = 0.005), and more often had at least 1 lead with notching (11 of 17 [65%] vs. 9 of 42 [21%], p = 0.001). The most sensitive characteristics for the detection of ARVD/C were a QRS duration in lead I of ≥120 ms (88% sensitivity, 91% negative predictive value). QRS transition at V(6) was most specific at 100% (100% positive predictive value, 77% negative predictive value). The presence of notching on any QRS complex had 79% sensitivity and 65% specificity of (55% positive predictive value, 85% negative predictive value). In multivariate analysis, QRS duration in lead I of ≥120 ms (odds ratio [OR]: 20.4, p = 0.034), earliest onset QRS in lead V(1) (OR: 17.0, p = 0.022), QRS notching (OR: 7.7, p = 0.018), and a transition of V(5) or later (OR: 7.0, p = 0.030) each predicted the presence of ARVD/C. CONCLUSIONS Several electrocardiographic criteria can help distinguish right ventricular outflow tract arrhythmias originating from ARVD/C compared with RVOT-VT patients.

Comparison of effectiveness of atorvastatin 10 mg versus 80 mg in reducing major cardiovascular events and repeat revascularization in patients with previous percutaneous coronary intervention (post hoc analysis of the Treating to New Targets [TNT] Study).

The Treating to New Targets (TNT) study demonstrated that intensive atorvastatin therapy to achieve low-density lipoprotein cholesterol concentrations well below recommended target levels provides an incremental clinical benefit in patients with stable coronary artery disease. This post hoc analysis of the TNT study was conducted to investigate whether this benefit extends to patients with previous percutaneous coronary intervention (PCI). A total of 10,001 patients with clinically evident coronary artery disease, including 5,407 patients with previous PCI, were randomized to atorvastatin 10 or 80 mg/day and followed for a median of 4.9 years. The primary end point was the occurrence of a first major cardiovascular event. Revascularization, a component of a secondary end point, was also examined. In patients with previous PCI, mean low-density lipoprotein cholesterol levels at study end were 79.5 mg/dl in the 80-mg arm and 100.8 mg/dl in the 10-mg arm. First major cardiovascular events occurred in 230 patients (8.6%) receiving high-dose atorvastatin and 289 patients (10.6%) receiving low-dose atorvastatin (hazard ratio 0.79, 95% confidence interval 0.67 to 0.94, p = 0.008). Repeat revascularization during follow-up (PCI or coronary artery bypass grafting) was performed in 466 patients (17.3%) in the 80-mg arm and 624 patients (22.9%) in the 10-mg arm (hazard ratio 0.73, 95% confidence interval 0.65 to 0.82, p <0.0001). In conclusion, intensive lipid lowering to a mean low-density lipoprotein cholesterol level of 79.5 mg/dl (2.1 mmol/L) with atorvastatin 80 mg/day in patients with previous PCI reduces major cardiovascular events by 21% and repeat revascularizations by 27% compared with a less intensive lipid-lowering regimen.

Internal Medicine Physicians' Perceptions Regarding Rate Versus Rhythm Control for Atrial Fibrillation

Atrial fibrillation (AF) is often managed by general internal medicine physicians. Available data suggest that guidelines regarding AF management are often not followed, but the reasons for this remain unknown. The aim of this study was to assess the knowledge and beliefs of internists regarding strategies to treat AF. A national electronic survey of internal medicine physicians regarding their perceptions of optimal AF management, with an emphasis on the rationale for choosing a rhythm- or rate-control strategy, was conducted. One hundred forty-eight physicians from 36 different states responded (representing > or =19% of unique e-mails opened). Half the respondents reported managing their patients with AF independently without referral to cardiologists. Seventy-three percent of participants believed that a rhythm-control strategy conveys a decreased stroke risk, 64% believed that there is a mortality benefit to rhythm control, and 55% thought that it would help avoid long-term anticoagulation. Comparing those who preferred a rhythm-control strategy to everyone else, those who favored rhythm control statistically significantly more often believed that rhythm control reduces the risk for stroke (96% vs 67%, p = 0.009) and that rhythm control allows the discontinuation of anticoagulation therapy (76% vs 49%, p = 0.045). In conclusion, contrary to available data in clinical trials and recent guidelines regarding the rationale for choosing a rhythm-control strategy in treating patients with AF, most study participants believed that rhythm control decreases stroke risk, decreases mortality, and allows the discontinuation of anticoagulation therapy. These prevalent misconceptions may substantially contribute to guideline nonadherence.

Comparison of radionuclide angiographic synchrony analysis to echocardiography and magnetic resonance imaging for the diagnosis of arrhythmogenic right ventricular cardiomyopathy

BACKGROUND Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heritable arrhythmia syndrome entailing a high risk of sudden cardiac death. Discernment from benign arrhythmia disorders, particularly right ventricular outflow tract ventricular tachycardia (RVOT VT), may be challenging, providing an impetus to explore alternative modalities that may facilitate evaluation of patients with suspected ARVC. OBJECTIVE We evaluated the role of equilibrium radionuclide angiography (ERNA) as a diagnostic tool for ARVC. METHODS ERNA measures of ventricular synchrony-synchrony (S) and entropy (E)-were examined in patients with ARVC (n = 16), those with RVOT VT (n = 13), and healthy controls (n = 49). The sensitivity and specificity of ERNA parameters for ARVC diagnosis were compared with those of echocardiography (ECHO) and cardiovascular magnetic resonance (CMR). RESULTS ERNA right ventricular synchrony parameters in patients with ARVC (S = 0.91 ± 0.07; E = 0.61 ± 0.1) differed significantly from those in patients with RVOT VT (S = 0.99 ± 0.01 [P = .0015]; E = 0.46 ± 0.05 [P < .001]) and healthy controls (S = 0.97 ± 0.02 [P = .003]; E = 0.48 ± 0.07 [P = .001]). The sensitivity of ERNA synchrony parameters for ARVC diagnosis (81%) was higher than that for ECHO (38%; P = .033) and similar to that for CMR (69%; P = .162), while specificity was lower for ERNA (89%) than that for ECHO and CMR (both 100%; P = .008). CONCLUSION ERNA right ventricular synchrony parameters can distinguish patients with ARVC from controls with structurally normal hearts, and its performance is comparable to that of ECHO and CMR for ARVC diagnosis. These findings suggest that ERNA may serve as a valuable imaging tool in the diagnostic evaluation of patients with suspected ARVC.

The Georgia Centenarian Study: Comments from Friends.

This paper discusses five issues related to the Georgia Centenarian Study: recruitment of centenarians, birth cohort effects, the changing age structure of the population, religion, and cognition and survival.

Plakoglobin Immunolocalization as a Diagnostic Test for Arrhythmogenic Right Ventricular Cardiomyopathy

A recent study using an anti‐plakoglobin antibody and immunofluorescence methods in endomyocardial tissue specimens found that a marked reduction in plakoglobin staining was highly sensitive and specific for the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC). The purpose of our study was to determine the diagnostic utility of plakoglobin immunolocalization using more standard immunoperoxidase methods suitable for clinical laboratories.

Bizarre and Wide QRS After Liver Transplant—Quiz Case

Colleen J. Johnson, MD, MS; Melvin A. Scheinman, MD; Mintu P. Turakhia, MD, MAS; Department of Medicine, Heart and Vascular Institute, Tulane University, New Orleans, Louisiana (Dr Johnson); Division of Cardiology, Department of Medicine, University of California, San Francisco (Dr Scheinman); Veterans Affairs Palo Alto Health Care System, Palo Alto, California (Dr Turakhia); Division of Cardiovascular Medicine, Department of Medicine, Stanford University, Stanford, California (Dr Turakhia)

Supraventricular Tachycardia: Where to Ablate?

This article presents a case of typical atrioventricular nodal reentrant tachycardia with eccentric atrial activation where the successful ablation site was within the coronary sinus. Although most typical atrioventricular nodal reentrant tachycardia, regardless of site of earliest retrograde activation, can be modified by traditional right-sided slow pathway modification, it is important to remember that ablation of left posterior nodal extensions within the coronary sinus or over the mitral annulus may afford the key to termination of tachycardia when standard approaches fail.

Ablation of Atrial Flutter in Congenital Heart Disease

A 42-year-old woman with a history of D-transposition of the great arteries and a Mustard correction at age 5 years presented to an outside hospital with palpitations and chest pain. The electrophysiology study and strategy for radiofrequency ablation are discussed.