Mehran Attari

Antibiotic‐induced Cardiac Arrhythmias

This review aims to clarify the underlying risk of arrhythmia associated with the use of macrolides and fluoroquinolones antibiotics. Torsades de pointes (TdP) is a rare potential side effect of fluoroquinolones and macrolide antibiotics. However, the widespread use of these antibiotics compounds the problem. These antibiotics prolong the phase 3 of the action potential and cause early after depolarization and dispersion of repolarization that precipitate TdP. The potency of these drugs, as potassium channel blockers, is very low, and differences between them are minimal. Underlying impaired cardiac repolarization is a prerequisite for arrhythmia induction. Impaired cardiac repolarization can be congenital in the young or acquired in adults. The most important risk factors are a prolonged baseline QTc interval or a combination with class III antiarrhythmic drugs. Modifiable risk factors, including hypokalemia, hypomagnesemia, drug interactions, and bradycardia, should be corrected. In the absence of a major risk factor, the incidence of TdP is very low. The use of these drugs in the appropriate settings of infection should not be altered because of the rare risk of TdP, except among cases with high-risk factors.

Catheter location, tracking, cardiac chamber geometry creation, and ablation using cutaneous patches.

Objective: The ability to construct a three-dimensional (3-D) surface model of the endocardium and track the location of catheters within a cardiac chamber, using only cutaneous patches, would be a useful advancement in treating arrhythmias. We tested the feasibility of such a system, Ensite NavX (Endocardial Solutions, Inc., St. Paul, MN, USA), in patients undergoing catheter ablation for SVTs.Methods: Sixteen patients with 20 arrhythmias undergoing ablation were selected. Skin electrode patches were placed on the chest to create a 3-D coordinate system. A low-amplitude, 5.7 kHz signal emitted from the patches was received by conventional catheters positioned in the heart.Catheter location was determined by measuring the field strength received by the catheters. Location points were successively acquired while catheters were moved throughout the chamber. This information was collected and processed by a workstation to create a detailed 3-D model of the endocardial surface. Anatomic landmarks were labeled on the model as the mapping catheter was navigated. 3-D cardiac chamber geometry reconstruction, landmark labeling, and real time catheter tracking were performed successfully in all patients. Up to six catheters, with a total of up to 26 intracardiac electrodes, were tracked simultaneously.Results: Constructed geometries, including major vessels and valves, correlated closely with traditional anatomic models as well as intracardiac recordings and fluoroscopic images.Conclusions: Real-time catheter tracking and 3-D cardiac chamber model construction is feasible using cutaneous patches and conventional catheters. This approach may be useful in the treatment of patients with cardiac arrhythmias where ablation therapy is primarily anatomically based.

Cardiac Sarcoidosis: The Impact of Age and Implanted Devices on Survival

Objective To assess the clinical characteristics, diagnosis, and outcome of cardiac sarcoidosis in a single institution sarcoidosis clinic. Methods Patients with cardiac sarcoidosis were identified using refined World Association of Sarcoidosis and Other Granulomatous Diseases (WASOG) criteria of highly probable and probable. Patient demographics, local and systemic treatments, and clinical outcome were collected. Results Of the 1,815 patients evaluated over a 6‐year period, 73 patients met the WASOG criteria for cardiac sarcoidosis. The median age at diagnosis was 46 years, with a median follow‐up of 8.8 years. Reduced left ventricular ejection fraction (LVEF) was the most common manifestation (54.8%). Patients with arrhythmias experienced ventricular tachycardia or severe heart block, (35.6% and 19.2%, respectively) with or without reduced LVEF. A total of 45 (61.6%) patients underwent cardiac PET scan and/or MRI, with 41 (91.1%) having a positive study. During follow‐up, 10 patients (13.7%) either underwent transplant (n = 3) or died (n = 7) from sarcoidosis. Kaplan‐Meier survival curves revealed 5‐ and 10‐year survival rates of 95.5% and 93.4%, respectively. Univariate factors of age at diagnosis < 46 years, implantation of pacemaker or defibrillator, mycophenolate treatment, or LVEF > 40% were associated with improved survival. Cox regression analysis demonstrated that age ≥ 46 years and lack of an implanted pacemaker or defibrillator were the only independent predictors of mortality. Conclusions The new WASOG criteria were able to characterize cardiac involvement in our sarcoidosis clinic. Age and lack of pacemaker or defibrillator were the significant predictors of mortality for cardiac sarcoidosis, and reduced LVEF < 40% was associated with worse prognosis. Trial Registry ClinicalTrials.gov; No.: NCT02356445; URL: www.clinicaltrials.gov.

Atheroscerlotic heart disease in Bangladeshi immigrants: risk factors and angiographic findings

BACKGROUND The prevalence of coronary artery disease (CAD) among Bangladeshis greatly exceeds that of Caucasians. Bangladeshis also suffer from premature onset, clinically aggressive and angiographically extensive disease. The role of conventional CAD risk factors (CCRFs) has been questioned. We therefore sought to determine if the CCRFs of Bangladeshis differed from non-Bangladeshis. We also sought to determine whether CAD was more extensive in Bangladeshis and if Bangladeshi ethnicity was independently predictive of extensive i.e., 3-vessel CAD at angiography. METHODS We reviewed the coronary angiograms and medical records of 75 Bangladeshis and 57 non-Bangladeshis presenting with myocardial infarction or angina pectoris. RESULTS Bangladeshis were younger (56.1 vs. 62.4 years, p=.001), had a lower body-mass index (25.2 vs. 27.2 kg/m(2), p=.017) and were less likely to be current or recent smokers (40% vs. 58%, p=.041) than non-Bangladeshis. There were no statistically significant differences in the proportion of subjects in the 2 groups with respect to diabetes mellitus, dyslipidemia, hypertension or family history of CAD. Bangladeshis had twice the rate of 3-vessel CAD of non-Bangladeshis (53% vs. 26%, p=.002). Bangladeshi ethnicity was independently associated with >3X the likelihood of having 3-vessel CAD at angiography (p=.011). CONCLUSIONS This study demonstrated that the CCRF burden of Bangladeshis with CAD is not excessive compared to that of non-Bangladeshis and is therefore unlikely to account for the excessive CAD risk found in this cohort. We also conclude that Bangladeshis have more angiographically extensive CAD than non-Bangladeshis and that Bangladeshi ethnicity is independently predictive of 3-vessel disease.

Ventricular Septal Defect Complicating an Acute Myocardial Infarction

A 66-year-old woman with no known medical history presented to the emergency department complaining of chest discomfort and difficulty breathing for the last 24 hours. She was in respiratory distress with a heart rate of 105 bpm and blood pressure of 115/65 mm Hg. The jugular venous pressure was elevated and there was a 4/6 holosystolic murmur across the precordium with a thrill. The ECG (Figure 1) showed acute anterior and inferior ST-segment elevation myocardial infarction (MI). The first total CK-MB fraction and troponin-I levels were 2001 U/L, 25.43 U/L, and 35 ng/mL, respectively. Coronary angiography …

Atrial fibrillation decision support tool: Population perspective

Background Appropriate thromboprophylaxis for patients with atrial fibrillation or atrial flutter (AF) remains a national challenge. The recent availability of direct oral anticoagulants (DOACs) with comparable efficacy and improved safety compared with warfarin alters the balance between risk factors for stroke and benefit of anticoagulation. Our objective was to examine the impact of DOACs as an alternative to warfarin on the net benefit of oral anticoagulant therapy (OAT) in a real‐world population of AF patients. Methods This is a retrospective cohort study of patients with paroxysmal or persistent nonvalvular AF. We updated an Atrial Fibrillation Decision Support Tool (AFDST) to include DOACs as treatment options. The tool generates patient‐specific recommendations based upon individual patient risk factor profiles for stroke and major bleeding using quality‐adjusted life‐years (QALYs) calculated for each treatment strategy by a decision analytic model. The setting included inpatient and ambulatory sites in an academic health center in the midwestern United States. The study involved 5,121 adults with nonvalvular AF seen for any ambulatory visit or inpatient hospitalization over the 1‐year period (January through December 2016). Outcome measure was net clinical benefit in QALYs. Results When DOACs are a therapeutic option, the AFDST recommends OAT for 4,134 (81%) patients and no antithrombotic therapy or aspirin for 489 (9%). A strong recommendation for OAT could not be made in 498 (10%) patients. When warfarin is the only option, OAT is recommended for 3,228 (63%) patients and no antithrombotic therapy or aspirin for 973 (19%). A strong recommendation for OAT could not be made in 920 (18%) patients. In total, 1,508 QALYs could be gained if treatment were changed to that recommended by the AFDST. Conclusions Availability of DOACs increases the proportion of patients for whom oral anticoagulation therapy is recommended in a real‐world cohort of AF patients and increased projected QALYs by more than 1,500 when all patients are receiving thromboprophylaxis as recommended by the AFDST compared with current treatment.

Hemodynamically significant atrial septal defect after atrial fibrillation ablation: A hole to remember

Case Report A 67-year-old woman was referred for cryoablation after flecainide therapy for symptomatic paroxysmal atrial fibrillation (PAF) was unsuccessful. A transesophageal echocardiogram performed immediately before the ablation was unremarkable. Double-transseptal puncture with a Brockenbrough needle through 8F SL0 and SL2 sheaths was performed. A Lasso catheter was advanced through the SL2 sheath into the left atrium and used to map all 4 pulmonary veins. The SL0 sheath was exchanged for a 15F FlexCath (Medtronic, Minneapolis, MN), and a 28-mm Arctic Front Cardiac CryoAblation Catheter (Medtronic) was used to isolate all pulmonary veins. A hockey stick maneuver was required to engage the right inferior pulmonary vein. The next day, color flow interrogation with a transthoracic echocardiogram demonstrated a small interatrial defect and left-to-right shunt (Figure 1). Over the next 3 months, the patient continued to have episodes of PAF, and she was eventually brought back for radiofrequency ablation (RFA). An echocardiogram performed before the procedure demonstrated mild right ventricular (RV) dilation, ventricular septum diastolic flattening, and a stable shunt. During the RFA, the interatrial septum was crossed through the iatrogenic atrial septal defect (iASD) with two 8.5F sheaths, and all the electrically reconnected veins were isolated successfully. Within days after the procedure, the patient began experiencing increasing dyspnea on exertion and fatigue. Workup with transthoracic echocardiogram and cardiac magnetic resonance imaging (Figure 2) showed moderate right atrial and RV dilation, an RV systolic pressure of 40 mm Hg, and a large atrial septal defect with a rim up to 1.1 cm (Figure 3). There was a significant left-to-right interatrial

Shared Decision-Making Tool for Thromboprophylaxis in Atrial Fibrillation – A Feasibility Study

Background: Appropriate thromboprophylaxis for patients with atrial fibrillation or atrial flutter (AF) remains a national challenge. Methods: We hypothesized that a shared decision‐making interaction facilitated by an Atrial Fibrillation Shared Decision Making Tool (AFSDM) would improve patient knowledge about atrial fibrillation, and the risks and benefits of various treatment options for stroke prevention; increase satisfaction with the decision‐making process; improve the therapeutic alliance between patient and the clinical care team; and increase medication adherence. Using a pre‐ and post‐visit study design, we enrolled 76 patients and completed 2 office visits and 1‐month telephone follow‐up for 65 patients being seen in our Arrhythmia Clinic over the 1‐year period (July 2016 through June 2017). Our primary outcome measure was change in decisional conflict between the first and second clinical visit. Results: Decisional conflict decreased from an average of 31 to 9. Mean change was 22.3 (95% CI, 25.7 ‐ 37.1), corresponding to an effect size of 0.94 standard deviations. Satisfaction with decision increased from 4.0 to 4.5, measures of therapeutic alliance with the care team (Kim Alliance scale) increased from 100.1 to 103.1, and satisfaction with provider increased from 4.2 to 4.5 (P < .0001 for all measures). AF knowledge assessment scores increased from 8.4 to 9.1, and knowledge about personal stroke and bleeding risk increased from 1 to 1.5 (P < .0001). Finally, medication adherence improved as reflected by an increase in the Morisky Medication Adherence scale from 5.9 to 6.4 (P < .0001). Conclusions: A shared decision‐making interaction, facilitated by an AFSDM can significantly improve multiple measures of decision‐making quality, leading to improved medication adherence and patient satisfaction.

RIGHT HEART FAILURE FROM PERSISTENT IATROGENIC ATRIAL SEPTAL DEFECT FOLLOWING ATRIAL FIBRILLATION ABLATION

Persistent iatrogenic atrial septal defect (iASD) has been reported in patients with a transseptal puncture performed for access to the left atrium. Majority of these resolve spontaneously and their clinical significance remains unknown. Here, we report a rare case of a symptomatic, persistent iASD